BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is ...BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion.展开更多
BACKGROUND Dexmedetomidine and propofol are two sedatives used for long-term sedation.It remains unclear whether dexmedetomidine provides superior cerebral protection for patients undergoing long-term mechanical venti...BACKGROUND Dexmedetomidine and propofol are two sedatives used for long-term sedation.It remains unclear whether dexmedetomidine provides superior cerebral protection for patients undergoing long-term mechanical ventilation.AIM To compare the neuroprotective effects of dexmedetomidine and propofol for sedation during prolonged mechanical ventilation in patients without brain injury.METHODS Patients who underwent mechanical ventilation for>72 h were randomly assigned to receive sedation with dexmedetomidine or propofol.The Richmond Agitation and Sedation Scale(RASS)was used to evaluate sedation effects,with a target range of-3 to 0.The primary outcomes were serum levels of S100-βand neuron-specific enolase(NSE)every 24 h.The secondary outcomes were remifentanil dosage,the proportion of patients requiring rescue sedation,and the time and frequency of RASS scores within the target range.RESULTS A total of 52 and 63 patients were allocated to the dexmedetomidine group and propofol group,respectively.Baseline data were comparable between groups.No significant differences were identified between groups within the median duration of study drug infusion[52.0(IQR:36.0-73.5)h vs 53.0(IQR:37.0-72.0)h,P=0.958],the median dose of remifentanil[4.5(IQR:4.0-5.0)μg/kg/h vs 4.6(IQR:4.0-5.0)μg/kg/h,P=0.395],the median percentage of time in the target RASS range without rescue sedation[85.6%(IQR:65.8%-96.6%)vs 86.7%(IQR:72.3%-95.3),P=0.592],and the median frequency within the target RASS range without rescue sedation[72.2%(60.8%-91.7%)vs 73.3%(60.0%-100.0%),P=0.880].The proportion of patients in the dexmedetomidine group who required rescue sedation was higher than in the propofol group with statistical significance(69.2%vs 50.8%,P=0.045).Serum S100-βand NSE levels in the propofol group were higher than in the dexmedetomidine group with statistical significance during the first six and five days of mechanical ventilation,respectively(all P<0.05).CONCLUSION Dexmedetomidine demonstrated stronger protective effects on the brain compared to propofol for long-term mechanical ventilation in patients without brain injury.展开更多
Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP lev...Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP levels have also been shown to closely impact hard endpoints such as mortality.Considering this,conducting an in-depth review ofΔP as a unique,outcome-impacting therapeutic modality is extremely important.There is a need to understand the subtleties involved in making sureΔP levels are optimized to enhance outcomes and minimize harm.We performed this narrative review to further explore the various uses ofΔP,the different parameters that can affect its use,and how outcomes vary in different patient populations at different pressure levels.To better utilizeΔP in MV-requiring patients,additional large-scale clinical studies are needed.展开更多
BACKGROUND At present,understanding of the most effective ventilation methods for treating chronic obstructive pulmonary disease(COPD)patients experiencing acute worsening symptoms and respiratory failure remains rela...BACKGROUND At present,understanding of the most effective ventilation methods for treating chronic obstructive pulmonary disease(COPD)patients experiencing acute worsening symptoms and respiratory failure remains relatively limited.This report analyzed the efficiency and side effects of various ventilation techniques used for individuals experiencing an acute COPD exacerbation.AIM To determine whether pressure-controlled ventilation(PCV)can lower peak airway pressures(PAPs)and reduce the incidence of barotrauma compared to volume-controlled ventilation(VCV),without compromising clinical outcomes and oxygenation parameters.METHODS We have evaluated 600 patients who were hospitalized due to a severe COPD exacerbation,with 400 receiving mechanical ventilation for the respiratory failure.The participants were divided into two different groups,who were administered either VCV or PCV,along with appropriate management.We thereafter observed patients'attributes,clinical factors,and laboratory,radiographic,and arterial blood gas evaluations at the start and during their stay in the intensive care unit(ICU).We have also employed appropriate statistical methods for the data analysis.RESULTS Both the VCV and PCV groups experienced significant enhancements in the respiratory rate,tidal volume,and arterial blood gas values during their time in the ICU.However,no significant distinctions were detected between the groups in terms of oxygenation indices(partial pressures of oxygen/raction of inspired oxygen ratio)and partial pressures of carbon dioxide improvements.There was no considerable disparity observed between the VCV and PCV groups in the hospital mortality(32%vs 28%,P=0.53),the number of days of ICU stay[median interquartile range(IQR):9(6-14)d vs 8(5-13)d,P=0.41],or the duration of the mechanical ventilation[median(IQR):6(4-10)d vs 5(3-9)d,P=0.47].The PCV group displayed lower PAPs compared to the VCV group(P<0.05)from the beginning of mechanical ventilation until extubation or ICU departure.The occurrence of barotrauma was considerably lower in the PCV group in comparison to the VCV group(6%vs 16%,P=0.03).CONCLUSION Both VCV and PCV were found to be effective in treating patients with acute COPD exacerbation.However,PCV was associated with lower PAPs and a significant decrease in barotrauma,thus indicating that it might be a safer ventilation method for this group of patients.However,further large-scale study is necessary to confirm these findings and to identify the best ventilation approach for patients experiencing an acute COPD exacerbation.展开更多
BACKGROUND Acute respiratory distress syndrome precipitates is widespread pulmonary injury in impacted individuals,the neonatal respiratory distress syndrome(NRDS),primarily observed in preterm infants,represents a pr...BACKGROUND Acute respiratory distress syndrome precipitates is widespread pulmonary injury in impacted individuals,the neonatal respiratory distress syndrome(NRDS),primarily observed in preterm infants,represents a prevalent critical condition in neonatal clinical settings.AIM To investigate the clinical efficacy of various ventilation strategies combined with pulmonary surfactant(PS)therapy in the treatment of NRDS.METHODS A total of 20 neonates diagnosed with respiratory distress syndrome,admitted between May 2021 and June 2022,were randomly assigned to either a research group or a control group.Neonates in the research group received treatment involving high-frequency oscillatory ventilation(HFOV)in conjunction with PS.In contrast,neonates in the control group were administered either controlled mechanical ventilation or synchronous intermittent mandatory ventilation,combined with PS.Arterial blood samples from the neonates in both groups were collected before treatment,as well as 6 h,12 h,24 h,and 48 h post-treatment.These samples underwent blood gas analysis,with measurements taken for pH value,partial pressures of oxygen(O_(2))and carbon dioxide.Concurrently,data was collected on the duration of ventilator use,length of hospitalization time,O_(2) treatment time,treatment outcomes,and complications of the ventilator.RESULTS From 6-48 h post-treatment,both groups demonstrated significant improvements in arterial blood pH and oxygen partial pressure,along with a significant decrease in carbon dioxide partial pressure compared to pre-treatment values(P<0.05).Although these changes progressed over time,there were no significant differences between the two groups(P>0.05).However,the research group had significantly lower X-ray scores,shorter hospitalization time,and less time on O_(2) therapy compared to the control group(P<0.05).Mortality rates were similar between the two groups(P>0.05),but the research group had a significantly lower incidence of complications(P<0.05).CONCLUSION The integration of HFOV combine with PS has proven to effectively expedite the treatment duration,decrease the occurrence of complications,and secure the therapeutic efficacy in managing NRDS.展开更多
Objective:To describe the strategies and outcomes of mechanical ventilation in a poorly equipped facility.Methods:This retrospective descriptive study included patients with COVID-19 who were admitted to the intensive...Objective:To describe the strategies and outcomes of mechanical ventilation in a poorly equipped facility.Methods:This retrospective descriptive study included patients with COVID-19 who were admitted to the intensive care unit(ICU)and mechanically ventilated between September 1,2020,and May 31,2021.Data were collected from medical records and databases.Results:54 Patients aged(62.9±13.3)years were included.Among these cases,79.6%had at least one comorbidity.On admission,all patients had hypoxia.The median peripheral oxygen saturation in room air was 76%(61%,83%).Non-invasive ventilation(NIV)was performed in 75.9%of the patients,and invasive mechanical ventilation(IMV)in 68.5%.IMV was performed on patients due to severe coma(8.1%),failure of standard oxygen therapy(27.0%),and failure of NIV(64.9%).An arterial blood gas test was performed in 14.8%of the patients.NIV failed in 90.2%of cases and succeeded in 9.8%.IMV was successful in 5.4%of cases,vs.94.6%of mortality.The overall mortality rate of patients on ventilation in the ICU was 88.9%.The causes of death included severe respiratory distress syndrome(85.2%),multiple organ failure(14.8%),and pulmonary embolism(13.0%).Conclusions:The ventilation management of COVID-19 patients in the ICU with NIV and IMV in a scarce resource setting is associated with a high mortality rate.Shortcomings are identified in ventilation strategies,protocols,and monitoring.Required improvements were also proposed.展开更多
Objective:To compare the survival and length of stay of invasive ventilation(IV)with those of non-invasive ventilation(NIV)in patients with COVID-19 acute respiratory distress syndrome in a single hospital from May 20...Objective:To compare the survival and length of stay of invasive ventilation(IV)with those of non-invasive ventilation(NIV)in patients with COVID-19 acute respiratory distress syndrome in a single hospital from May 2020 to March 2021.Methods:After obtaining approval from the Hospital Director,the data of COVID-19 patients including demographics,type of respiratory support(non-invasive ventilation or invasive ventilation),duration of ventilation,length of stay,discharge,and death were collected and analyzed.Results:Out of the 152 patients identified,134 patients were analyzed.The median intubation days were 10.0(Q1:3.5,Q3:13.5)in the IV group and 0.0(Q1:0.0,Q3:0.0)days in the NIV-only group.Out of the 101 patients who received NIV,43 patients were subsequently intubated due to failure of NIV.Of the 63 patients(47.01%)who died,22(66.66%)were from the IV group and 40(92.02%)were from the NIV-followed-by-intubation group,and 1(1.72%)were from the NIV-only group.Multivariate analysis showed that the presence of a respiratory comorbidity(OR=16.56,95%CI=1.56-175.48,P=0.02)was an independent predictor of survival.Conclusions:Respiratory co-morbidity is a significant adverse predictor of survival outcome.The decision on the type of respiratory support should be made on a patient-to-patient basis.展开更多
The numerical simulations and experimental results of an ultra-broadband acoustic ventilation barrier composed of periodic unit cells are reported in this paper.Based on multiple mechanisms,including sound absorption ...The numerical simulations and experimental results of an ultra-broadband acoustic ventilation barrier composed of periodic unit cells are reported in this paper.Based on multiple mechanisms,including sound absorption by eigenmodes of the unit cell and sound reflection by a plate structure on upper surface of the unit cell,a single-layer ventilation barrier with broadband sound reduction is designed,and its working bandwidth can reach about 1560 Hz.The experimental results accord well with the simulation results.Furthermore,two types of three-layer ventilation barriers are designed and demonstrated by using the unit cells with different values of a(the length of the hollow square region)and w(the width of the channel between the adjacent cavities),and the bandwidths of both ventilation barriers can increase to 3160 Hz and 3230 Hz,respectively.The designed barrier structures have the advantages of ultra-broadband sound reduction and ventilation,which paves the way to designing high-performance ventilation barriers for the applications in environmental protection and architectural acoustics.展开更多
BACKGROUND Alphaherpesvirus belongs to the Herpesviridae family and has large,monopartite double-stranded linear DNA.It mainly infects the skin,mucosa,and nerves,and can affect various hosts,including humans and other...BACKGROUND Alphaherpesvirus belongs to the Herpesviridae family and has large,monopartite double-stranded linear DNA.It mainly infects the skin,mucosa,and nerves,and can affect various hosts,including humans and other animals.Here,we present a case of a patient seen by the gastroenterology department at our hospital who experienced an oral and perioral herpes infection following treatment with a ven-tilator.The patient was treated with oral and topical antiviral drugs,furacilin,oral and topical antibiotics,local epinephrine injection,topical thrombin powder,and nutritional and supportive care.A wet wound healing approach was also implemented with good response.CASE SUMMARY A 73-year-old woman presented to the hospital with a chief complaint of"abdominal pain for 3 d with dizziness for 2 d."She was admitted to the intensive care unit for septic shock and spontaneous peritonitis secondary to cirrhosis and was given antiinflammatory and symptomatic supportive treatment.A ventilator was used to assist breathing for acute respiratory distress syndrome,which developed during her admission.A large area of herpes infection appeared in the perioral region 2 d following noninvasive ventilation.The patient was transferred to the gastroenterology department,at which time she had a body temperature of 37.8 C and a respiratory rate of 18/min.The patient's con-sciousness was intact,and she no longer had abdominal pain or distension,chest tightness,or asthma.At this point,the infected perioral region changed in appearance and was now accompanied by local bleeding with crusting of blood at the wounds.The surface area of the wounds measured approximately 10 cm×10 cm.A cluster blisters appeared on the patient’s right neck,and ulcers developed in her mouth.On a subjective numerical pain scale,the patient reported a pain level of 2.Overall,her diagnoses other than the oral and perioral herpes infection included:(1)Septic shock;(2)spontaneous peritonitis;(3)abdominal infection;(4)decompensated cirrhosis;and(5)hypoproteinemia.Dermatology was consulted regarding the treatment of the patient’s wounds;they suggested treatment with oral antiviral drugs,an intramuscular injection of nutritious nerve drugs,and the application of topical penciclovir and mupirocin around the lips.Stomatology was also consulted and suggested the use of nitrocilin in a local wet application around the lips.CONCLUSION Through multidisciplinary consultation,the patient’s oral and perioral herpes infection was successfully treated with the following combined approach:(1)Application of topical antviral and antibiotic treatments;(2)keeping the wound moist with a wet wound healing strategy;(3)systemic use of oral antiviral drugs;and(4)symptomatic and nutritional supportive care.The patient was discharged from the hospital after successful wound healing.展开更多
A study is conducted to optimize the geometry of a solar chimney equipped with a horizontal absorber in order to improve its performances in relation to the provision of ventilation.The problem is tackled through nume...A study is conducted to optimize the geometry of a solar chimney equipped with a horizontal absorber in order to improve its performances in relation to the provision of ventilation.The problem is tackled through numerical solution of the governing equations for mass,momentum and energy in their complete three-dimensional and unsteady formulation.The numerical framework also includes a turbulence model(k-ε)and a radiant heat transfer(DO)model.Moreover,a Multi-Objective Genetic Algorithm(MOGA)is employed to derive the optimal configuration of the considered solar chimney.It is shown that an air velocity of 0.2 m/s can be obtained.This value is the minimum allowed air velocity according to the ASHRAE’s(American Society of Heating,Refrigerating and Air-Conditioning Engineers)adaptive comfort approach.展开更多
Background: One-lung ventilation (OLV) is generally adopted for thoracic surgery. The systemic application of a high fraction of inspiratory oxygen (F<sub>1</sub>O<sub>2</sub>) and continuous p...Background: One-lung ventilation (OLV) is generally adopted for thoracic surgery. The systemic application of a high fraction of inspiratory oxygen (F<sub>1</sub>O<sub>2</sub>) and continuous positive airway pressure (CPAP) to the non-ventilated lung is useful for preventing arterial oxygen desaturation. The adverse effects of elevated F<sub>1</sub>O<sub>2</sub> include oxidative lung injury, resorption atelectasis and coronary and peripheral vasoconstriction. It is preferable to avoid hyperoxemia in patients with complications such as chronic obstructive pulmonary disease, idiopathic pneumonia, and bleomycin-treated lungs. We aimed to determine whether the application of 60% O<sub>2</sub> CPAP to the non-ventilated lung is sufficient to provide adequate oxygenation with 60% O<sub>2</sub> to the ventilated lung. Methods: A total of 70 patients scheduled to receive elective thoracic surgery requiring OLV were recruited. Left double-lumen tubes were applicable in all surgeries. Patients were randomly allocated to one of two groups, to receive either 60% O<sub>2</sub> CPAP (60% CPAP group, n = 35), or 100% O<sub>2</sub> CPAP (100% CPAP group, n = 35) at a setting of 2 - 3 cmH<sub>2</sub>O, applied to the non-ventilated lung. Arterial blood gas analyses were obtained at the following stages: RA, spontaneous breathing under room air (RA);TLV, during total lung ventilation (TLV) prior to the initiation of OLV;T5, 5 min after the initiation of OLV;T15, 15 min after the initiation of OLV;T30, 30 min after the initiation of OLV. Results: The PaO<sub>2</sub> value in 60% CPAP group vs. 100% CPAP group at each measurement were as follows: RA (mean [standard deviation: SD], 89.7 [8.2] mmHg vs. 85.8 [11.9] mmHg);TLV (277.9 [52.9] mmHg vs. 269.2 [44.0] mmHg);T5 (191.4 [67.9] mmHg vs. 192.3 [66.0] mmHg);T15 (143.2 [67.3] mmHg vs. 154.7 [60.8] mmHg) and T30 (95.6 [32.0] mmHg vs. 112.5 [36.5] mmHg), respectively. Among the five measurement points, T30 was the only time point at which the 100% CPAP group showed a significantly greater PaO<sub>2</sub> value than the 60% CPAP group (p = 0.0495). The SaO<sub>2</sub> at T30 in the 100% CPAP group (97.4 [2.0]%) was also significantly greater than that in the 60% CPAP group (96.3 [2.2]%, p = 0.039). No differences were found between the groups regarding changes to the overall PaO<sub>2</sub> values (p = 0.44) and SaO<sub>2</sub> values (p = 0.23) during the study period. Conclusions: Oxygenation could be safely maintained in relatively healthy patients with 60% O<sub>2</sub> OLV and 60% O<sub>2</sub> CPAP. The application of 60% O<sub>2</sub> CPAP during OLV for patients who are not suited to exposure to high F<sub>1</sub>O<sub>2</sub> may be an alternative form of respiratory management.展开更多
BACKGROUND Monitoring of gastric residual is an important approach for assessing gastric emptying in patients with mechanical ventilation.By monitoring gastric contents,the enteral nutrition scheme can be adjusted in ...BACKGROUND Monitoring of gastric residual is an important approach for assessing gastric emptying in patients with mechanical ventilation.By monitoring gastric contents,the enteral nutrition scheme can be adjusted in time to ensure feeding safety.AIM To investigate the effects of ultrasound monitoring on the incidence of feeding complications,daily caloric intake and prognosis of patients with severe mechanical ventilation.To analyze the clinical significance of ultrasound monitoring of gastric residual volume(GRV)up to 250 mL to provide a theoretical basis for clinical practice.METHODS Patients admitted to the department of emergency medicine of the Affiliated Hospital of Nantong University from January 2018 to June 2022 who received invasive mechanical ventilation and continuous enteral nutrition support within 24-48 h after admission were enrolled in this study.Medical records for patients within 7 d of hospitalization were retrospectively analyzed to compare the incidence of feeding complications,daily caloric intake and clinical prognosis between patients with gastric residual≥250 mL and<250 mL,as monitored by ultrasound on the third day.RESULTS A total of 513 patients were enrolled in this study.Incidences of abdominal distension,diarrhea,and vomiting in the<250 mL and≥250 mL groups were:18.4%vs 21.0%,23.9%vs 32.3%and 4.0%vs 6.5%,respectively;mortality rates were 20.8%vs 22.65%;mechanical ventilation durations were 18.30 d vs 17.56 d while lengths of stay in the intensive care units(ICU)were 19.87 d vs 19.19±5.19 d.Differences in the above factors between groups were not significant.Gastric residual≥250 mL was not an independent risk factor for death and prolonged ICU stay.However,target feeding time of patients in the≥250 mL group was longer than that of patients in the≥250 mL group,and caloric intake(22.0,23.6,24.8,25.3 kcal/kg/d)for patients in the≥250 mL group from the 4^(th) day to the 7^(th) day of hospitalization was lower than that of patients in the≥250 mL group(23.2,24.8,25.7,25.8 kcal/kg/d).On the 4^(th) day(Z=4.324,P=0.013),on the 5^(th) day(Z=3.376,P=0.033),while on the 6^(th) day(Z=3.098,P=0.04),the differences were statistically significant.CONCLUSION The use of ultrasound to monitor GRV and undertaking clinical interventions when the monitoring value is≥250 mL has no significant effects on incidences of feeding complications and clinical prognostic outcomes,however,it significantly prolongs the time to reach target feeding,reduces the daily intake of calories during ICU hospitalization,and increases the risk of insufficient nutrition of patients.The accuracy and necessity of monitoring gastric remnants and monitoring frequencies should be investigated further.展开更多
Natural ventilation effects in high and large space buildings of tropical areas greatlya ffect the air conditioning energy consumption.Aiming at nearly zero energy building design,thisp aper mainly contributes to prov...Natural ventilation effects in high and large space buildings of tropical areas greatlya ffect the air conditioning energy consumption.Aiming at nearly zero energy building design,thisp aper mainly contributes to provide theoretical basis and reference for thermal comfortable air conditioning system design of high and large space buildings.Taking a theatre in Hainan as study object,a newly composite enhanced natural ventilation system is proposed by integrating theu nderground tunnel-based earth to air heat exchange system and the solar chimney.Ventilationq uantity,air velocity and air temperature field,human vertical temperature gradient differenceu nder24simulation working conditions are considered and analyzed by using ANSYS Fluent.Fort he underground tunnel,results show that Group Two with double underground tunnels and side airs upply location shows its advantages in cooling effects and air supply uniformity.Then for the solar chimney,results show that the solar radiation intensity contributes to larger difference int ransmission power and leads to different cooling effects.On the whole,the system under workingc ondition No.7with120m long,side air supply,double underground tunnel and20m high,1mw ide,0.6°absorber plate angle solar chimney shows its priority in better comprehensive performance.展开更多
The causes of an offensive odor in the kitchens,bathrooms,and toilets of residential apartments in multi-story buildings with natural ventilation in Tomsk,Russia,are discussed in this paper.This problem exists in othe...The causes of an offensive odor in the kitchens,bathrooms,and toilets of residential apartments in multi-story buildings with natural ventilation in Tomsk,Russia,are discussed in this paper.This problem exists in other cities and countries.Wall electric fans can be installed in ventilation grills in kitchens,bathrooms,and toilets of apartments in multi-story residential buildings.Typically,these fans turn on with the light in the bathroom or toilet,so the problem is periodic.Forced airflow from a fan in one apartment disrupts the natural outflow of air in the ventilation system of a residential building designed and built according to building codes and regulations and can cause an unpleasant smell in neighboring apartments.In many cases,it is difficult to determine which apartments have fans and force the neighbors to remove them.Locally,on the scale of one apartment,the problem is solved by installing an air check valve in the ventilation grill,which will block the nuisance airflow from the ventilation system into the bathroom.Globally,the problem is solved by modification and subsequent compliance with building codes and regulations,the implementation of which is controlled by local authorities.展开更多
BACKGROUND Studies have shown elevated C-reactive protein(CRP)to predict mechanical ventilation(MV)in patients with coronavirus disease 2019(COVID-19).Its utility is unknown in patients with chronic kidney disease(CKD...BACKGROUND Studies have shown elevated C-reactive protein(CRP)to predict mechanical ventilation(MV)in patients with coronavirus disease 2019(COVID-19).Its utility is unknown in patients with chronic kidney disease(CKD),who have elevated baseline CRP levels due to chronic inflammation and reduced renal clearance.AIM To assess whether an association exists between elevated inflammatory markers and MV rate in patients with stagesⅢb-ⅤCKD and COVID-19.METHODS We conducted a retrospective cohort study on patients with COVID-19 and stagesⅢb-ⅤCKD.The primary outcome was the rate of invasive MV,the rate of noninvasive MV,and the rate of no MV.Statistical analyses used unpaired t-test for continuous variables and chi-square analysis for categorical variables.Cutoffs for variables were CRP:100 mg/L,ferritin:530 ng/mL,D-dimer:0.5 mg/L,and lactate dehydrogenase(LDH):590 U/L.RESULTS 290 were screened,and 118 met the inclusion criteria.CRP,D-dimer,and ferritin were significantly different among the three groups.On univariate analysis for invasive MV(IMV),CRP had an odds ratio(OR)-5.44;ferritin,OR-2.8;LDH,OR-7.7;D-dimer,OR-3.9,(P<0.05).The admission CRP level had an area under curve-receiver operator characteristic(AUROC):0.747 for the IMV group(sensitivity-80.8%,specificity-50%)and 0.663 for the non-IMV(NIMV)group(area under the curve,sensitivity-69.2%,specificity-53%).CONCLUSION Our results demonstrate a positive correlation between CRP,ferritin,and D-dimer levels and MV and NIMV rates in CKD patients.The AUROC demonstrates a good sensitivity for CRP levels in detecting the need for MV in patients with stagesⅢb-ⅤCKD.This may be because of the greater magnitude of increased inflammation due to COVID-19 itself compared with increased inflammation and reduced clearance due to CKD alone.展开更多
Objective:To investigate the effect of Yiqi Huoxue decoction combined with neuromuscular electrical stimulation on improving intensive care unit(ICU)acquired debility in mechanically ventilated patients.Methods:50 pat...Objective:To investigate the effect of Yiqi Huoxue decoction combined with neuromuscular electrical stimulation on improving intensive care unit(ICU)acquired debility in mechanically ventilated patients.Methods:50 patients who were admitted to the ICU and received mechanical ventilation treatment in our hospital from June 2022 to June 2023 and were complicated with ICU-acquired neurasthenia were selected,and randomly grouped using the randomized envelope method into two groups:control group with 25 patients who received neuromuscular electrical stimulation alone;observation group with 25 patients who received the traditional Chinese medicine Yiqi Huoxue decoction.Comparison indexes:treatment efficiency,degree of emotional recovery(APACHEⅡscore),muscle strength status(MRC score),motor status(FAC rating),and self-care ability(BI index score).Results:The treatment efficiency of patients in the observation group patients was higher as compared to those in the control group(P<0.05).There was no significant difference in the comparison of the results of the scores(ratings)of each index between the two groups before treatment(P>0.05).After the treatment,the APACHEⅡscores of patients in the observation group were significantly lower as compared to those in the control group,while the MRC scores,FAC ratings,and BI index scores were higher in the observation group than those of the control group patients(P<0.05).Conclusion:The combined application of Yiqi Huoxue decoction and neuromuscular electrical stimulation in the treatment of patients with ICU-acquired neurasthenia complicated by mechanical ventilation significantly enhanced the clinical efficacy,the patient’s muscle strength,motor status,and ability of self-care.Hence,it has high application value and is worthy to be popularized.展开更多
Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.M...Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:68 patients with COPD combined with respiratory failure treated in our hospital from September 2021 to October 2023 were selected as the research subjects.Using the random number table method,they were divided into a control group and an experimental group of 34 cases each.The control group received conventional symptomatic treatment,and the experimental group received non-invasive ventilator treatment based on the control group.The clinical effects,blood gas indicators(partial pressure of carbon dioxide(PaCO_(2)),partial pressure of oxygen(PaO_(2)),arterial oxygen saturation(SaO_(2))),lung function(forced expiratory volume in 1 second(FEV1),forced vital capacity(FVC),6 min walking distance),complications,and inflammatory factor levels(c-reactive protein(CRP),interleukin-6(IL-6),neutrophil-to-lymphocyte ratio(NLR))of the two groups of patients were observed.Results:(1)The clinical efficacy of the patients in the experimental group(33/97.06%)was more significant as compared with the control group(25/73.53%)(P<0.05);(2)After treatment,the clinical efficacy of the two groups of patients in terms of FEV1,FEV1/FVC,6-minute walking distance,PaO_(2)and SaO_(2)all increased in the experimental group as compared to that of the control group(P<0.05);(3)After treatment,the PaCO_(2),CRP,IL-6,and NLR of the two groups of patients decreased,and the decrease in the experimental group was higher than that of the control group(P<0.05);(4)The patients’complication rate in the experimental group(2/5.88%)was lower as compared to that of the control group(9/26.46%)(P<0.05).Conclusion:Non-invasive ventilators combined with conventional therapy achieved good clinical results in treating patients with COPD and respiratory failure.展开更多
The purpose of ventilation management systems is to ensure the health and safety of underground workers by creating and incorporating structured plans, procedures and processes on the day-to-day operations of the mine...The purpose of ventilation management systems is to ensure the health and safety of underground workers by creating and incorporating structured plans, procedures and processes on the day-to-day operations of the mine ventilation system. The application of ventilation management programs consists of audit, verification, and corrective action procedures to:(1) ensure adherence to regulatory standards,or to(2) return to compliance and safety standards when an upset condition arises. This paper describes how a ventilation management program can be developed and implemented to ensure regulation compliance, to increase safety, to improve operational efficiency and to reduce the operating costs of an operating mine. Two case applications are presented in this paper. The first case is presented to demonstrate use of a ventilation management program in response to a site inspection and audit, with follow-up application of corrective actions. The second case application describes how air quality conditions has been substantially improved with the development and implementation of a ventilation management program for an operating underground hard rock mine.展开更多
The internal flow field study of car compartments is an important step in railroad vehicle design and optimization. The flow field profile has a significant impact on the temperature distribution and passenger comfort...The internal flow field study of car compartments is an important step in railroad vehicle design and optimization. The flow field profile has a significant impact on the temperature distribution and passenger comfort level. Experimental studies on flow field can yield accurate results but carry a high time and computational cost. In contrast, the numerical simulation method can yield an internal flow field profile in less time than an experimental study. This study aims to improve the computational efficiency of numerical simulation by adapting two simplified models—the porous media model and the porous jump face model—to study the internal flow field of a railroad car compartment. The results provided by both simplified models are compared with the original numerical simulation model and with experimental data. Based on the results, the porous media model has a better agreement with the original model and with the experimental results. The flow field parameters (temperature and velocity) of the porous media model have relatively small numerical errors, with a maximum numerical error of 4.7%. The difference between the numerical results of the original model and those of the porous media model is less than 1%. By replacing the original numerical simulation model with the porous media model, the flow field of subway car compartments can be calculated with a reduction of about 25% in computing resources, while maintaining good accuracy.展开更多
文摘BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion.
文摘BACKGROUND Dexmedetomidine and propofol are two sedatives used for long-term sedation.It remains unclear whether dexmedetomidine provides superior cerebral protection for patients undergoing long-term mechanical ventilation.AIM To compare the neuroprotective effects of dexmedetomidine and propofol for sedation during prolonged mechanical ventilation in patients without brain injury.METHODS Patients who underwent mechanical ventilation for>72 h were randomly assigned to receive sedation with dexmedetomidine or propofol.The Richmond Agitation and Sedation Scale(RASS)was used to evaluate sedation effects,with a target range of-3 to 0.The primary outcomes were serum levels of S100-βand neuron-specific enolase(NSE)every 24 h.The secondary outcomes were remifentanil dosage,the proportion of patients requiring rescue sedation,and the time and frequency of RASS scores within the target range.RESULTS A total of 52 and 63 patients were allocated to the dexmedetomidine group and propofol group,respectively.Baseline data were comparable between groups.No significant differences were identified between groups within the median duration of study drug infusion[52.0(IQR:36.0-73.5)h vs 53.0(IQR:37.0-72.0)h,P=0.958],the median dose of remifentanil[4.5(IQR:4.0-5.0)μg/kg/h vs 4.6(IQR:4.0-5.0)μg/kg/h,P=0.395],the median percentage of time in the target RASS range without rescue sedation[85.6%(IQR:65.8%-96.6%)vs 86.7%(IQR:72.3%-95.3),P=0.592],and the median frequency within the target RASS range without rescue sedation[72.2%(60.8%-91.7%)vs 73.3%(60.0%-100.0%),P=0.880].The proportion of patients in the dexmedetomidine group who required rescue sedation was higher than in the propofol group with statistical significance(69.2%vs 50.8%,P=0.045).Serum S100-βand NSE levels in the propofol group were higher than in the dexmedetomidine group with statistical significance during the first six and five days of mechanical ventilation,respectively(all P<0.05).CONCLUSION Dexmedetomidine demonstrated stronger protective effects on the brain compared to propofol for long-term mechanical ventilation in patients without brain injury.
文摘Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP levels have also been shown to closely impact hard endpoints such as mortality.Considering this,conducting an in-depth review ofΔP as a unique,outcome-impacting therapeutic modality is extremely important.There is a need to understand the subtleties involved in making sureΔP levels are optimized to enhance outcomes and minimize harm.We performed this narrative review to further explore the various uses ofΔP,the different parameters that can affect its use,and how outcomes vary in different patient populations at different pressure levels.To better utilizeΔP in MV-requiring patients,additional large-scale clinical studies are needed.
文摘BACKGROUND At present,understanding of the most effective ventilation methods for treating chronic obstructive pulmonary disease(COPD)patients experiencing acute worsening symptoms and respiratory failure remains relatively limited.This report analyzed the efficiency and side effects of various ventilation techniques used for individuals experiencing an acute COPD exacerbation.AIM To determine whether pressure-controlled ventilation(PCV)can lower peak airway pressures(PAPs)and reduce the incidence of barotrauma compared to volume-controlled ventilation(VCV),without compromising clinical outcomes and oxygenation parameters.METHODS We have evaluated 600 patients who were hospitalized due to a severe COPD exacerbation,with 400 receiving mechanical ventilation for the respiratory failure.The participants were divided into two different groups,who were administered either VCV or PCV,along with appropriate management.We thereafter observed patients'attributes,clinical factors,and laboratory,radiographic,and arterial blood gas evaluations at the start and during their stay in the intensive care unit(ICU).We have also employed appropriate statistical methods for the data analysis.RESULTS Both the VCV and PCV groups experienced significant enhancements in the respiratory rate,tidal volume,and arterial blood gas values during their time in the ICU.However,no significant distinctions were detected between the groups in terms of oxygenation indices(partial pressures of oxygen/raction of inspired oxygen ratio)and partial pressures of carbon dioxide improvements.There was no considerable disparity observed between the VCV and PCV groups in the hospital mortality(32%vs 28%,P=0.53),the number of days of ICU stay[median interquartile range(IQR):9(6-14)d vs 8(5-13)d,P=0.41],or the duration of the mechanical ventilation[median(IQR):6(4-10)d vs 5(3-9)d,P=0.47].The PCV group displayed lower PAPs compared to the VCV group(P<0.05)from the beginning of mechanical ventilation until extubation or ICU departure.The occurrence of barotrauma was considerably lower in the PCV group in comparison to the VCV group(6%vs 16%,P=0.03).CONCLUSION Both VCV and PCV were found to be effective in treating patients with acute COPD exacerbation.However,PCV was associated with lower PAPs and a significant decrease in barotrauma,thus indicating that it might be a safer ventilation method for this group of patients.However,further large-scale study is necessary to confirm these findings and to identify the best ventilation approach for patients experiencing an acute COPD exacerbation.
文摘BACKGROUND Acute respiratory distress syndrome precipitates is widespread pulmonary injury in impacted individuals,the neonatal respiratory distress syndrome(NRDS),primarily observed in preterm infants,represents a prevalent critical condition in neonatal clinical settings.AIM To investigate the clinical efficacy of various ventilation strategies combined with pulmonary surfactant(PS)therapy in the treatment of NRDS.METHODS A total of 20 neonates diagnosed with respiratory distress syndrome,admitted between May 2021 and June 2022,were randomly assigned to either a research group or a control group.Neonates in the research group received treatment involving high-frequency oscillatory ventilation(HFOV)in conjunction with PS.In contrast,neonates in the control group were administered either controlled mechanical ventilation or synchronous intermittent mandatory ventilation,combined with PS.Arterial blood samples from the neonates in both groups were collected before treatment,as well as 6 h,12 h,24 h,and 48 h post-treatment.These samples underwent blood gas analysis,with measurements taken for pH value,partial pressures of oxygen(O_(2))and carbon dioxide.Concurrently,data was collected on the duration of ventilator use,length of hospitalization time,O_(2) treatment time,treatment outcomes,and complications of the ventilator.RESULTS From 6-48 h post-treatment,both groups demonstrated significant improvements in arterial blood pH and oxygen partial pressure,along with a significant decrease in carbon dioxide partial pressure compared to pre-treatment values(P<0.05).Although these changes progressed over time,there were no significant differences between the two groups(P>0.05).However,the research group had significantly lower X-ray scores,shorter hospitalization time,and less time on O_(2) therapy compared to the control group(P<0.05).Mortality rates were similar between the two groups(P>0.05),but the research group had a significantly lower incidence of complications(P<0.05).CONCLUSION The integration of HFOV combine with PS has proven to effectively expedite the treatment duration,decrease the occurrence of complications,and secure the therapeutic efficacy in managing NRDS.
文摘Objective:To describe the strategies and outcomes of mechanical ventilation in a poorly equipped facility.Methods:This retrospective descriptive study included patients with COVID-19 who were admitted to the intensive care unit(ICU)and mechanically ventilated between September 1,2020,and May 31,2021.Data were collected from medical records and databases.Results:54 Patients aged(62.9±13.3)years were included.Among these cases,79.6%had at least one comorbidity.On admission,all patients had hypoxia.The median peripheral oxygen saturation in room air was 76%(61%,83%).Non-invasive ventilation(NIV)was performed in 75.9%of the patients,and invasive mechanical ventilation(IMV)in 68.5%.IMV was performed on patients due to severe coma(8.1%),failure of standard oxygen therapy(27.0%),and failure of NIV(64.9%).An arterial blood gas test was performed in 14.8%of the patients.NIV failed in 90.2%of cases and succeeded in 9.8%.IMV was successful in 5.4%of cases,vs.94.6%of mortality.The overall mortality rate of patients on ventilation in the ICU was 88.9%.The causes of death included severe respiratory distress syndrome(85.2%),multiple organ failure(14.8%),and pulmonary embolism(13.0%).Conclusions:The ventilation management of COVID-19 patients in the ICU with NIV and IMV in a scarce resource setting is associated with a high mortality rate.Shortcomings are identified in ventilation strategies,protocols,and monitoring.Required improvements were also proposed.
文摘Objective:To compare the survival and length of stay of invasive ventilation(IV)with those of non-invasive ventilation(NIV)in patients with COVID-19 acute respiratory distress syndrome in a single hospital from May 2020 to March 2021.Methods:After obtaining approval from the Hospital Director,the data of COVID-19 patients including demographics,type of respiratory support(non-invasive ventilation or invasive ventilation),duration of ventilation,length of stay,discharge,and death were collected and analyzed.Results:Out of the 152 patients identified,134 patients were analyzed.The median intubation days were 10.0(Q1:3.5,Q3:13.5)in the IV group and 0.0(Q1:0.0,Q3:0.0)days in the NIV-only group.Out of the 101 patients who received NIV,43 patients were subsequently intubated due to failure of NIV.Of the 63 patients(47.01%)who died,22(66.66%)were from the IV group and 40(92.02%)were from the NIV-followed-by-intubation group,and 1(1.72%)were from the NIV-only group.Multivariate analysis showed that the presence of a respiratory comorbidity(OR=16.56,95%CI=1.56-175.48,P=0.02)was an independent predictor of survival.Conclusions:Respiratory co-morbidity is a significant adverse predictor of survival outcome.The decision on the type of respiratory support should be made on a patient-to-patient basis.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.12174159,12274183,and 51976079)the National Key Research and Development Program of China (Grant No.2020YFC1512403)the Research Project of State Key Laboratory of Mechanical System and Vibration (Grant No.MSV202201)。
文摘The numerical simulations and experimental results of an ultra-broadband acoustic ventilation barrier composed of periodic unit cells are reported in this paper.Based on multiple mechanisms,including sound absorption by eigenmodes of the unit cell and sound reflection by a plate structure on upper surface of the unit cell,a single-layer ventilation barrier with broadband sound reduction is designed,and its working bandwidth can reach about 1560 Hz.The experimental results accord well with the simulation results.Furthermore,two types of three-layer ventilation barriers are designed and demonstrated by using the unit cells with different values of a(the length of the hollow square region)and w(the width of the channel between the adjacent cavities),and the bandwidths of both ventilation barriers can increase to 3160 Hz and 3230 Hz,respectively.The designed barrier structures have the advantages of ultra-broadband sound reduction and ventilation,which paves the way to designing high-performance ventilation barriers for the applications in environmental protection and architectural acoustics.
基金Supported by the Construction Fund of Key Medical Disciplines of Hangzhou,No.OO20200265the Basic Public Welfare Research Project of Zhejiang Province,No.LGF22H250005+1 种基金General project of Hangzhou Health Science and Technology Plan,No.A20200320Zhejiang Provincial Medical and Health Technology Project,No.2020PY016.
文摘BACKGROUND Alphaherpesvirus belongs to the Herpesviridae family and has large,monopartite double-stranded linear DNA.It mainly infects the skin,mucosa,and nerves,and can affect various hosts,including humans and other animals.Here,we present a case of a patient seen by the gastroenterology department at our hospital who experienced an oral and perioral herpes infection following treatment with a ven-tilator.The patient was treated with oral and topical antiviral drugs,furacilin,oral and topical antibiotics,local epinephrine injection,topical thrombin powder,and nutritional and supportive care.A wet wound healing approach was also implemented with good response.CASE SUMMARY A 73-year-old woman presented to the hospital with a chief complaint of"abdominal pain for 3 d with dizziness for 2 d."She was admitted to the intensive care unit for septic shock and spontaneous peritonitis secondary to cirrhosis and was given antiinflammatory and symptomatic supportive treatment.A ventilator was used to assist breathing for acute respiratory distress syndrome,which developed during her admission.A large area of herpes infection appeared in the perioral region 2 d following noninvasive ventilation.The patient was transferred to the gastroenterology department,at which time she had a body temperature of 37.8 C and a respiratory rate of 18/min.The patient's con-sciousness was intact,and she no longer had abdominal pain or distension,chest tightness,or asthma.At this point,the infected perioral region changed in appearance and was now accompanied by local bleeding with crusting of blood at the wounds.The surface area of the wounds measured approximately 10 cm×10 cm.A cluster blisters appeared on the patient’s right neck,and ulcers developed in her mouth.On a subjective numerical pain scale,the patient reported a pain level of 2.Overall,her diagnoses other than the oral and perioral herpes infection included:(1)Septic shock;(2)spontaneous peritonitis;(3)abdominal infection;(4)decompensated cirrhosis;and(5)hypoproteinemia.Dermatology was consulted regarding the treatment of the patient’s wounds;they suggested treatment with oral antiviral drugs,an intramuscular injection of nutritious nerve drugs,and the application of topical penciclovir and mupirocin around the lips.Stomatology was also consulted and suggested the use of nitrocilin in a local wet application around the lips.CONCLUSION Through multidisciplinary consultation,the patient’s oral and perioral herpes infection was successfully treated with the following combined approach:(1)Application of topical antviral and antibiotic treatments;(2)keeping the wound moist with a wet wound healing strategy;(3)systemic use of oral antiviral drugs;and(4)symptomatic and nutritional supportive care.The patient was discharged from the hospital after successful wound healing.
文摘A study is conducted to optimize the geometry of a solar chimney equipped with a horizontal absorber in order to improve its performances in relation to the provision of ventilation.The problem is tackled through numerical solution of the governing equations for mass,momentum and energy in their complete three-dimensional and unsteady formulation.The numerical framework also includes a turbulence model(k-ε)and a radiant heat transfer(DO)model.Moreover,a Multi-Objective Genetic Algorithm(MOGA)is employed to derive the optimal configuration of the considered solar chimney.It is shown that an air velocity of 0.2 m/s can be obtained.This value is the minimum allowed air velocity according to the ASHRAE’s(American Society of Heating,Refrigerating and Air-Conditioning Engineers)adaptive comfort approach.
文摘Background: One-lung ventilation (OLV) is generally adopted for thoracic surgery. The systemic application of a high fraction of inspiratory oxygen (F<sub>1</sub>O<sub>2</sub>) and continuous positive airway pressure (CPAP) to the non-ventilated lung is useful for preventing arterial oxygen desaturation. The adverse effects of elevated F<sub>1</sub>O<sub>2</sub> include oxidative lung injury, resorption atelectasis and coronary and peripheral vasoconstriction. It is preferable to avoid hyperoxemia in patients with complications such as chronic obstructive pulmonary disease, idiopathic pneumonia, and bleomycin-treated lungs. We aimed to determine whether the application of 60% O<sub>2</sub> CPAP to the non-ventilated lung is sufficient to provide adequate oxygenation with 60% O<sub>2</sub> to the ventilated lung. Methods: A total of 70 patients scheduled to receive elective thoracic surgery requiring OLV were recruited. Left double-lumen tubes were applicable in all surgeries. Patients were randomly allocated to one of two groups, to receive either 60% O<sub>2</sub> CPAP (60% CPAP group, n = 35), or 100% O<sub>2</sub> CPAP (100% CPAP group, n = 35) at a setting of 2 - 3 cmH<sub>2</sub>O, applied to the non-ventilated lung. Arterial blood gas analyses were obtained at the following stages: RA, spontaneous breathing under room air (RA);TLV, during total lung ventilation (TLV) prior to the initiation of OLV;T5, 5 min after the initiation of OLV;T15, 15 min after the initiation of OLV;T30, 30 min after the initiation of OLV. Results: The PaO<sub>2</sub> value in 60% CPAP group vs. 100% CPAP group at each measurement were as follows: RA (mean [standard deviation: SD], 89.7 [8.2] mmHg vs. 85.8 [11.9] mmHg);TLV (277.9 [52.9] mmHg vs. 269.2 [44.0] mmHg);T5 (191.4 [67.9] mmHg vs. 192.3 [66.0] mmHg);T15 (143.2 [67.3] mmHg vs. 154.7 [60.8] mmHg) and T30 (95.6 [32.0] mmHg vs. 112.5 [36.5] mmHg), respectively. Among the five measurement points, T30 was the only time point at which the 100% CPAP group showed a significantly greater PaO<sub>2</sub> value than the 60% CPAP group (p = 0.0495). The SaO<sub>2</sub> at T30 in the 100% CPAP group (97.4 [2.0]%) was also significantly greater than that in the 60% CPAP group (96.3 [2.2]%, p = 0.039). No differences were found between the groups regarding changes to the overall PaO<sub>2</sub> values (p = 0.44) and SaO<sub>2</sub> values (p = 0.23) during the study period. Conclusions: Oxygenation could be safely maintained in relatively healthy patients with 60% O<sub>2</sub> OLV and 60% O<sub>2</sub> CPAP. The application of 60% O<sub>2</sub> CPAP during OLV for patients who are not suited to exposure to high F<sub>1</sub>O<sub>2</sub> may be an alternative form of respiratory management.
基金The study was conducted in accordance with the Declaration of Helsinki(as revised in 2013).The study was approved by the Ethics Committee of Affiliated Hospital of Nantong University(Approval No.2022015).
文摘BACKGROUND Monitoring of gastric residual is an important approach for assessing gastric emptying in patients with mechanical ventilation.By monitoring gastric contents,the enteral nutrition scheme can be adjusted in time to ensure feeding safety.AIM To investigate the effects of ultrasound monitoring on the incidence of feeding complications,daily caloric intake and prognosis of patients with severe mechanical ventilation.To analyze the clinical significance of ultrasound monitoring of gastric residual volume(GRV)up to 250 mL to provide a theoretical basis for clinical practice.METHODS Patients admitted to the department of emergency medicine of the Affiliated Hospital of Nantong University from January 2018 to June 2022 who received invasive mechanical ventilation and continuous enteral nutrition support within 24-48 h after admission were enrolled in this study.Medical records for patients within 7 d of hospitalization were retrospectively analyzed to compare the incidence of feeding complications,daily caloric intake and clinical prognosis between patients with gastric residual≥250 mL and<250 mL,as monitored by ultrasound on the third day.RESULTS A total of 513 patients were enrolled in this study.Incidences of abdominal distension,diarrhea,and vomiting in the<250 mL and≥250 mL groups were:18.4%vs 21.0%,23.9%vs 32.3%and 4.0%vs 6.5%,respectively;mortality rates were 20.8%vs 22.65%;mechanical ventilation durations were 18.30 d vs 17.56 d while lengths of stay in the intensive care units(ICU)were 19.87 d vs 19.19±5.19 d.Differences in the above factors between groups were not significant.Gastric residual≥250 mL was not an independent risk factor for death and prolonged ICU stay.However,target feeding time of patients in the≥250 mL group was longer than that of patients in the≥250 mL group,and caloric intake(22.0,23.6,24.8,25.3 kcal/kg/d)for patients in the≥250 mL group from the 4^(th) day to the 7^(th) day of hospitalization was lower than that of patients in the≥250 mL group(23.2,24.8,25.7,25.8 kcal/kg/d).On the 4^(th) day(Z=4.324,P=0.013),on the 5^(th) day(Z=3.376,P=0.033),while on the 6^(th) day(Z=3.098,P=0.04),the differences were statistically significant.CONCLUSION The use of ultrasound to monitor GRV and undertaking clinical interventions when the monitoring value is≥250 mL has no significant effects on incidences of feeding complications and clinical prognostic outcomes,however,it significantly prolongs the time to reach target feeding,reduces the daily intake of calories during ICU hospitalization,and increases the risk of insufficient nutrition of patients.The accuracy and necessity of monitoring gastric remnants and monitoring frequencies should be investigated further.
基金Sponsored by the National Natural Science Foundation of Guangdong Province(Grant No.2020A1515011092)the Open Projects Fund of KeyL aboratory of Ecology and Energy-saving Study of Dense Habitat(Tongji University),Ministry of Education(Grant No.2020030105)。
文摘Natural ventilation effects in high and large space buildings of tropical areas greatlya ffect the air conditioning energy consumption.Aiming at nearly zero energy building design,thisp aper mainly contributes to provide theoretical basis and reference for thermal comfortable air conditioning system design of high and large space buildings.Taking a theatre in Hainan as study object,a newly composite enhanced natural ventilation system is proposed by integrating theu nderground tunnel-based earth to air heat exchange system and the solar chimney.Ventilationq uantity,air velocity and air temperature field,human vertical temperature gradient differenceu nder24simulation working conditions are considered and analyzed by using ANSYS Fluent.Fort he underground tunnel,results show that Group Two with double underground tunnels and side airs upply location shows its advantages in cooling effects and air supply uniformity.Then for the solar chimney,results show that the solar radiation intensity contributes to larger difference int ransmission power and leads to different cooling effects.On the whole,the system under workingc ondition No.7with120m long,side air supply,double underground tunnel and20m high,1mw ide,0.6°absorber plate angle solar chimney shows its priority in better comprehensive performance.
基金support from the Government of the Russian Federation (Mega grant No.075-15-2021-612 of June 4,2021) for funding scientific research in Russia.
文摘The causes of an offensive odor in the kitchens,bathrooms,and toilets of residential apartments in multi-story buildings with natural ventilation in Tomsk,Russia,are discussed in this paper.This problem exists in other cities and countries.Wall electric fans can be installed in ventilation grills in kitchens,bathrooms,and toilets of apartments in multi-story residential buildings.Typically,these fans turn on with the light in the bathroom or toilet,so the problem is periodic.Forced airflow from a fan in one apartment disrupts the natural outflow of air in the ventilation system of a residential building designed and built according to building codes and regulations and can cause an unpleasant smell in neighboring apartments.In many cases,it is difficult to determine which apartments have fans and force the neighbors to remove them.Locally,on the scale of one apartment,the problem is solved by installing an air check valve in the ventilation grill,which will block the nuisance airflow from the ventilation system into the bathroom.Globally,the problem is solved by modification and subsequent compliance with building codes and regulations,the implementation of which is controlled by local authorities.
文摘BACKGROUND Studies have shown elevated C-reactive protein(CRP)to predict mechanical ventilation(MV)in patients with coronavirus disease 2019(COVID-19).Its utility is unknown in patients with chronic kidney disease(CKD),who have elevated baseline CRP levels due to chronic inflammation and reduced renal clearance.AIM To assess whether an association exists between elevated inflammatory markers and MV rate in patients with stagesⅢb-ⅤCKD and COVID-19.METHODS We conducted a retrospective cohort study on patients with COVID-19 and stagesⅢb-ⅤCKD.The primary outcome was the rate of invasive MV,the rate of noninvasive MV,and the rate of no MV.Statistical analyses used unpaired t-test for continuous variables and chi-square analysis for categorical variables.Cutoffs for variables were CRP:100 mg/L,ferritin:530 ng/mL,D-dimer:0.5 mg/L,and lactate dehydrogenase(LDH):590 U/L.RESULTS 290 were screened,and 118 met the inclusion criteria.CRP,D-dimer,and ferritin were significantly different among the three groups.On univariate analysis for invasive MV(IMV),CRP had an odds ratio(OR)-5.44;ferritin,OR-2.8;LDH,OR-7.7;D-dimer,OR-3.9,(P<0.05).The admission CRP level had an area under curve-receiver operator characteristic(AUROC):0.747 for the IMV group(sensitivity-80.8%,specificity-50%)and 0.663 for the non-IMV(NIMV)group(area under the curve,sensitivity-69.2%,specificity-53%).CONCLUSION Our results demonstrate a positive correlation between CRP,ferritin,and D-dimer levels and MV and NIMV rates in CKD patients.The AUROC demonstrates a good sensitivity for CRP levels in detecting the need for MV in patients with stagesⅢb-ⅤCKD.This may be because of the greater magnitude of increased inflammation due to COVID-19 itself compared with increased inflammation and reduced clearance due to CKD alone.
文摘Objective:To investigate the effect of Yiqi Huoxue decoction combined with neuromuscular electrical stimulation on improving intensive care unit(ICU)acquired debility in mechanically ventilated patients.Methods:50 patients who were admitted to the ICU and received mechanical ventilation treatment in our hospital from June 2022 to June 2023 and were complicated with ICU-acquired neurasthenia were selected,and randomly grouped using the randomized envelope method into two groups:control group with 25 patients who received neuromuscular electrical stimulation alone;observation group with 25 patients who received the traditional Chinese medicine Yiqi Huoxue decoction.Comparison indexes:treatment efficiency,degree of emotional recovery(APACHEⅡscore),muscle strength status(MRC score),motor status(FAC rating),and self-care ability(BI index score).Results:The treatment efficiency of patients in the observation group patients was higher as compared to those in the control group(P<0.05).There was no significant difference in the comparison of the results of the scores(ratings)of each index between the two groups before treatment(P>0.05).After the treatment,the APACHEⅡscores of patients in the observation group were significantly lower as compared to those in the control group,while the MRC scores,FAC ratings,and BI index scores were higher in the observation group than those of the control group patients(P<0.05).Conclusion:The combined application of Yiqi Huoxue decoction and neuromuscular electrical stimulation in the treatment of patients with ICU-acquired neurasthenia complicated by mechanical ventilation significantly enhanced the clinical efficacy,the patient’s muscle strength,motor status,and ability of self-care.Hence,it has high application value and is worthy to be popularized.
文摘Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:68 patients with COPD combined with respiratory failure treated in our hospital from September 2021 to October 2023 were selected as the research subjects.Using the random number table method,they were divided into a control group and an experimental group of 34 cases each.The control group received conventional symptomatic treatment,and the experimental group received non-invasive ventilator treatment based on the control group.The clinical effects,blood gas indicators(partial pressure of carbon dioxide(PaCO_(2)),partial pressure of oxygen(PaO_(2)),arterial oxygen saturation(SaO_(2))),lung function(forced expiratory volume in 1 second(FEV1),forced vital capacity(FVC),6 min walking distance),complications,and inflammatory factor levels(c-reactive protein(CRP),interleukin-6(IL-6),neutrophil-to-lymphocyte ratio(NLR))of the two groups of patients were observed.Results:(1)The clinical efficacy of the patients in the experimental group(33/97.06%)was more significant as compared with the control group(25/73.53%)(P<0.05);(2)After treatment,the clinical efficacy of the two groups of patients in terms of FEV1,FEV1/FVC,6-minute walking distance,PaO_(2)and SaO_(2)all increased in the experimental group as compared to that of the control group(P<0.05);(3)After treatment,the PaCO_(2),CRP,IL-6,and NLR of the two groups of patients decreased,and the decrease in the experimental group was higher than that of the control group(P<0.05);(4)The patients’complication rate in the experimental group(2/5.88%)was lower as compared to that of the control group(9/26.46%)(P<0.05).Conclusion:Non-invasive ventilators combined with conventional therapy achieved good clinical results in treating patients with COPD and respiratory failure.
文摘The purpose of ventilation management systems is to ensure the health and safety of underground workers by creating and incorporating structured plans, procedures and processes on the day-to-day operations of the mine ventilation system. The application of ventilation management programs consists of audit, verification, and corrective action procedures to:(1) ensure adherence to regulatory standards,or to(2) return to compliance and safety standards when an upset condition arises. This paper describes how a ventilation management program can be developed and implemented to ensure regulation compliance, to increase safety, to improve operational efficiency and to reduce the operating costs of an operating mine. Two case applications are presented in this paper. The first case is presented to demonstrate use of a ventilation management program in response to a site inspection and audit, with follow-up application of corrective actions. The second case application describes how air quality conditions has been substantially improved with the development and implementation of a ventilation management program for an operating underground hard rock mine.
文摘The internal flow field study of car compartments is an important step in railroad vehicle design and optimization. The flow field profile has a significant impact on the temperature distribution and passenger comfort level. Experimental studies on flow field can yield accurate results but carry a high time and computational cost. In contrast, the numerical simulation method can yield an internal flow field profile in less time than an experimental study. This study aims to improve the computational efficiency of numerical simulation by adapting two simplified models—the porous media model and the porous jump face model—to study the internal flow field of a railroad car compartment. The results provided by both simplified models are compared with the original numerical simulation model and with experimental data. Based on the results, the porous media model has a better agreement with the original model and with the experimental results. The flow field parameters (temperature and velocity) of the porous media model have relatively small numerical errors, with a maximum numerical error of 4.7%. The difference between the numerical results of the original model and those of the porous media model is less than 1%. By replacing the original numerical simulation model with the porous media model, the flow field of subway car compartments can be calculated with a reduction of about 25% in computing resources, while maintaining good accuracy.
