The direct delivery of inhaled antibiotics to the respiratory tract has been a subject of enduring interest among medical practitioners and researchers due to the associated favorable pharmacokinetics.This interest ha...The direct delivery of inhaled antibiotics to the respiratory tract has been a subject of enduring interest among medical practitioners and researchers due to the associated favorable pharmacokinetics.This interest has been particularly pronounced in the context of critically illpatients,wherehealthcare-associatedpulmonary infections represent a significant challenge,driving continued exploration of inhaled antibiotics for intubated patients.Recent high-level evidence has shown a very promising application in the field of ventilator-associated pneumonia (VAP) prevention.^([1]).展开更多
Objective: To investigate the efficacy, safety and nursing improvement of noninvasive positive pressure ventilation (NPPV) in high-risk patients with acute respiratory failure after cardiac surgery. Methods: From Sept...Objective: To investigate the efficacy, safety and nursing improvement of noninvasive positive pressure ventilation (NPPV) in high-risk patients with acute respiratory failure after cardiac surgery. Methods: From September 2018 to October 2019, high-risk patients who may develop acute respiratory failure after cardiac surgery were selected and randomly divided into non-invasive ventilation group and conventional treatment group (control group). The reintubation rate, tracheotomy rate, fatality rate, 24 h intake and output, respiratory rate, arterial blood gas PaO2 and PaCO2 were compared between the two groups of patients;at the same time, the patient comfort and mask leakage after improved nursing technology were compared. Results: The preoperative and intraoperative conditions of the two groups of patients were basically similar, but the reintubation rate, tracheotomy rate, fatality rate, and respiratory rate of the patients in the preventive application of NPPV group were significantly lower than those of the control group, and the 24 h input and output and arterial blood gas PaO2 were also excellent in the control group. Conclusion: NPPV used prophylactically in high-risk patients after cardiac surgery can significantly reduce the re-intubation rate, improve patient outcomes, and is markedly more effective than the conventional treatment group.展开更多
Objective: To investigate the effect of extracorporeal diaphragmatic pacing combined with noninvasive ventilators on the respiratory function and prognosis of chronic obstructive pulmonary disease (COPD) patients. Met...Objective: To investigate the effect of extracorporeal diaphragmatic pacing combined with noninvasive ventilators on the respiratory function and prognosis of chronic obstructive pulmonary disease (COPD) patients. Methods: A total of 50 COPD patients were selected between January 2023 to December 2023 and randomly grouped into an observation group and a control group, with 25 cases. The observation group was given extracorporeal diaphragm pacing combined with a noninvasive ventilator, while the control group was given a conventional treatment mode. After the treatment, the results of each index in the two groups were compared. Results: Compared with the diaphragm function indexes of the two groups, the data of the observation group were more dominant (P < 0.05). The rehospitalization rate of the observation group was lower than that of the control group (P < 0.05). The COPD assessment test (CAT) and mMRC (Modified Medical Research Council) Dyspnoea scale scores after treatment between the two groups were significantly different (P < 0.05). Compared with the control group, the lung function indexes of the observation group were more dominant (P < 0.05). Conclusion: Extracorporeal diaphragmatic pacing combined with a noninvasive ventilator promoted the improvement of the patient’s prognosis and improved their respiratory function.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
Mechanical ventilation is a specialized oxygen therapy and life support technology with significant importance for critically ill patients. In fact, 40%–66% of patients in the intensive care unit(ICU) require mechani...Mechanical ventilation is a specialized oxygen therapy and life support technology with significant importance for critically ill patients. In fact, 40%–66% of patients in the intensive care unit(ICU) require mechanical ventilation.^([1,2]) However, the mechanical ventilation can lead to ventilatorassociated lung injury(VALI),^([3]) ultimately resulting in difficulties in weaning from mechanical ventilation,prolonged hospital stays, and even increased mortality.展开更多
A recent study on the rapid imaging of pulmonary ventilation using hyperpolarized ^(129)Xe MRI has demonstrated the ability to achieve isotropic 3D ventilation imaging with a spatial resolution of 3×3×3mm^(3...A recent study on the rapid imaging of pulmonary ventilation using hyperpolarized ^(129)Xe MRI has demonstrated the ability to achieve isotropic 3D ventilation imaging with a spatial resolution of 3×3×3mm^(3) in humans,within an acquisition time of just 3.5 seconds(https://doi.org/10.1002/mrm.30120).展开更多
During the train meeting events,train equipment compartments are exposed to the worst pressure changes,potentially affecting the ventilation performance of equipment,particularly for electrical facilities equipped wit...During the train meeting events,train equipment compartments are exposed to the worst pressure changes,potentially affecting the ventilation performance of equipment,particularly for electrical facilities equipped with independent air ducts.In this paper,a two-step method is used for numerical computation:(1)obtaining the temporal and spatial transient node data of the flow field sections during the train-passing simulation and(2)using the data as the input data for the equipment compartment simulation.In addition,this paper also compares the difference in equipment ventilation between the single-train and trainpassing scenarios in real vehicle tests.The results indicate that the primary factors influencing ventilation effectiveness are the aerodynamic compression and deceleration of airflow induced by the other train's nose,as well as the instability of the external flow field in the wake of the other train.During train crossing,the air is forced into the air duct,with a maximum ratio of the airflow in-duct to the airflow out-duct reaching 3.2.The average mass flow falls below the rated mass flow for the converter.Compared to the rated air volume of converter,the maximum suppression rates obtained from testing and simulation are-24.5%and-16.8%,respectively.Compared to the single-train operation,the maximum suppression rates obtained from testing and simulation are-15%and-18%,respectively.These findings provide valuable insights into the design and operation of high-speed trains.展开更多
Indoor air quality(IAQ)is often overlooked,yet a poorly maintained environment can lead to significant health issues and reduced concentration and productivity in work or educational settings.This study presents an in...Indoor air quality(IAQ)is often overlooked,yet a poorly maintained environment can lead to significant health issues and reduced concentration and productivity in work or educational settings.This study presents an innovative control system for mechanical ventilation specifically designed for university classrooms,with the dual goal of enhancing IAQ and increasing energy efficiency.Two classrooms with distinct construction characteristics were analyzed:one with exterior walls and windows,and the other completely underground.For each classroom,a model was developed using DesignBuilder software,which was calibrated with experimental data regarding CO_(2) concentration,temperature,and relative humidity levels.The proposed ventilation system operates based on CO_(2) concentration,relative humidity,and potential for free heating and cooling.In addition,the analysis was conducted for other locations,demonstrating consistent energy savings across different climates and environments,always showing an annual reduction in energy consumption.Results demonstrate that mechanical ventilation,when integrated with heat recovery and free cooling strategies,significantly reduces energy consumption by up to 25%,while also maintaining optimal CO_(2) levels to enhance comfort and air quality.These findings emphasize the essential need for well-designed mechanical ventilation systems to ensure both psychophysical well-being and IAQ in enclosed spaces,particularly in environments intended for extended occupancy,such as classrooms.Furthermore,this approach has broad applicability,as it could be adapted to various building types,thereby contributing to sustainable energy management practices and promoting healthier indoor spaces.This study serves as a model for future designs aiming to balance energy efficiency with indoor air quality,especially relevant in the post-COVID era,where the importance of indoor air quality has become more widely recognized.展开更多
BACKGROUND:We sought to evaluate the risk factors for developing ventilator-associated pneumonia(VAP)and whether the location of intubation posed a risk in trauma patients.METHODS:Data were retrospectively reviewed fo...BACKGROUND:We sought to evaluate the risk factors for developing ventilator-associated pneumonia(VAP)and whether the location of intubation posed a risk in trauma patients.METHODS:Data were retrospectively reviewed for adult trauma patients requiring intubation for>48 hours,admitted between 2010 and 2013.Patients’demographics,clinical presentations and outcomes were compared according to intubation location(prehospital intubation[PHI]vs.trauma room[TRI])and presence vs.absence of VAP.Multivariate regression analysis was performed to identify predictors of VAP.RESULTS:Of 471 intubated patients,332 patients met the inclusion criteria(124 had PHI and208 had TRI)with a mean age of 30.7±14.8 years.PHI group had lower GCS(P=0.001),respiratory rate(P=0.001),and higher frequency of head(P=0.02)and chest injuries(P=0.04).The rate of VAP in PHI group was comparable to the TRI group(P=0.60).Patients who developed VAP were 6 years older,had significantly lower GCS and higher ISS,head AIS,and higher rates of polytrauma.The overall mortality was 7.5%,and was not associated with intubation location or pneumonia rates.In the early-VAP group,gram-positive pathogens were more common,while gram-negative microorganisms were more frequently encountered in the late VAP group.Logistic regression analysis and modeling showed that the impact of the location of intubation in predicting the risk of VAP appeared only when chest injury was included in the models.CONCLUSION:In trauma,the risk of developing VAP is multifactorial.However,the location of intubation and presence of chest injury could play an important role.展开更多
AIM: To determine the incidence, etiology, risk factors and outcome of ventilator-associated pneumonia(VAP) in patients undergoing orthotopic liver transplantation(OLT).METHODS: This retrospective study considered 242...AIM: To determine the incidence, etiology, risk factors and outcome of ventilator-associated pneumonia(VAP) in patients undergoing orthotopic liver transplantation(OLT).METHODS: This retrospective study considered 242 patients undergoing deceased donor OLT. VAP was diagnosed according to clinical and microbiological criteria. RESULTS: VAP occurred in 18(7.4%) patients, with an incidence of 10 per 1000 d of mechanical ventilation(MV). Isolated bacterial etiologic agents were mainly Enterobacteriaceae(79%). Univariate logistic analysis showed that model for end-stage liver disease(MELD) score, pre-operative hospitalization, treatment with terlipressin, Child-Turcotte-Pugh score, days of MV and red cell transfusion were risk factors for VAP. Multivariateanalysis, considering significant risk factors in univariate analysis, demonstrated that pneumonia was strongly associated with terlipressin usage, pre-operative hospitalization, days of MV and red cell transfusion. Mortality rate was 22% in the VAP group vs 4% in the group without VAP. CONCLUSION: Our data suggest that VAP is an important cause of nosocomial infection during postoperative period in OLT patients. MELD score was a significant risk factor in univariate analysis. Multiple transfusions, treatment with terlipressin, preoperative hospitalization rather than called to the hospital while at home and days of MV constitute important risk factors for VAP development.展开更多
BACKGROUND: Data on the mechanical ventilation(MV) characteristics and radiologic features for the cases with H7 N9-induced ARDS were still lacking.METHODS: We describe the MV characteristics and radiologic features o...BACKGROUND: Data on the mechanical ventilation(MV) characteristics and radiologic features for the cases with H7 N9-induced ARDS were still lacking.METHODS: We describe the MV characteristics and radiologic features of adult patients with ARDS due to microbiologically confirmed H7 N9 admitted to our ICU over a 3-month period.RESULTS: Eight patients(mean age 57.38±16.75; 5 male) were diagnosed with H7 N9 in the first quarter of 2014. All developed respiratory failure complicated by acute respiratory distress syndrome(ARDS), which required MV in ICU. The baseline APACHE II and SOFA score was 11.77±6.32 and 7.71±3.12. The overall CT scores of the patients was 247.68±34.28 and the range of CT scores was 196.3–294.7. The average MV days was 14.63±6.14, and 4 patients required additional rescue therapies for refractory hypoxemia. Despite these measures, 3 patients died.CONCLUSION: In H7 N9-infected patients with ARDS, low tidal volume strategy was the conventional mode. RM as one of rescue therapies to refractory hypoxemia in these patients with serious architectural distortion and high CT scores, which could cause further lung damage, may induce bad outcomes and requires serious consideration. Prone ventilation may improve mortality, and should be performed at the early stage of the disease, not as a rescue therapy.展开更多
Objective： Ventilator associated pneumonia （VAP） has been shown to be associated with significant morbidity and mortality（ Chastre and Fagon, 2002; klompas, 2007） among mechanically venti- lated patients in the i...Objective： Ventilator associated pneumonia （VAP） has been shown to be associated with significant morbidity and mortality（ Chastre and Fagon, 2002; klompas, 2007） among mechanically venti- lated patients in the intensive care unit （ICU）, with the incidence ranging from 9% to 27% ; crude mortality ranges from 25% to 50%.1-3 A meta-analysis of published studies was undertaken to combine information regarding the effect of subglottic secretion drainage （SSD） on the incidence of ventilated associated pneumonia in adult ICU patients. Methods： Reports of studies on SSD were identified by searching the PUBMED, EMBASE, and COCHRANCE LIBRARY databases （December 30, 2010）. Randomized trials of SSD compared to usual care in adult mechanically ventilated ICU patients were included in this meta-analysis. Results： Ten RCTs with 2,314 patients were identified. SSD significantly reduced the incidence of VAP [ relative risk （RR） =0.52, 95% confidence interval （C/）： 0.42-0.64, P〈0.000 01]. When SSD was compared with the control groups, the overall RR for ICU mortality was 1.00 （95% CI, 0.84-1.19） and for hospital mortality was 0.95 （95% CI, 0. 80-1.13）. Overall, the subglottic drainage effect on the days of mechanical ventilation was -1.52 days （95% CI, -2.94 to -0.11） and on the ICU length of stay （LOS） was -0.81days （95% CI, -2.33 to -0.7）. Conclusions： In this meta-analysis, when an endotracheal tube （ETT） with SSD was compared with an ETT without SSD, there was a highly significant reduction in the VAP rate of approxi- mately 50%. Time on mechanical ventilation （MV） and the ICU LOS may be reduced, but no reduction in ICU or hospital mortality has been observed in published trials,展开更多
Expiratory flow limitation(EFL), that is the inability of expiratory flow to increase in spite of an increase of the driving pressure, is a common and unrecognized occurrence during mechanical ventilation in a variety...Expiratory flow limitation(EFL), that is the inability of expiratory flow to increase in spite of an increase of the driving pressure, is a common and unrecognized occurrence during mechanical ventilation in a variety of intensive care unit conditions. Recent evidence suggests that the presence of EFL is associated with an increase in mortality, at least in acute respiratory distress syndrome(ARDS) patients, and in pulmonary complications in patients undergoing surgery. EFL is a major cause of intrinsic positive end-expiratory pressure(PEEPi), which in ARDS patients is heterogeneously distributed, with a consequent increase of ventilation/perfusion mismatch and reduction of arterial oxygenation. Airway collapse is frequently concomitant to the presence of EFL.When airways close and reopen during tidal ventilation, abnormally high stresses are generated that can damage the bronchiolar epithelium and uncouple small airways from the alveolar septa, possibly generating the small airways abnormalities detected at autopsy in ARDS. Finally, the high stresses and airway distortion generated downstream the choke points may contribute to parenchymal injury, but this possibility is still unproven. PEEP application can abolish EFL, decrease PEEPi heterogeneity, and limit recruitment/derecruitment.Whether increasing PEEP up to EFL disappearance is a useful criterion for PEEP titration can only be determined by future studies.展开更多
OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive A...OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive Airway Pressure)ventilation on the upper airway of the patient through a household respiratory machine.However,if the ventilator mask is designed improperly,it might cause the residue and repeated inhalation of CO2,which will exert an adverse impact on the therapeutic effect.Present research numerically analyzed the CO2 transportation inside a commercial ventilator mask(Mirage SoftGel,ResMed,Australia)based on the reconstructed 3D numerical model of a volunteer's face and performed the improved design of the ventilator mask in terms of the CO2 residual concentration below the nostrils.The fluid dynamic analyses showed that at the end time of expiratory,the CO2 residual concentration below the nostrils is close to 4%.To improve the therapeutic effect,we changed the position of the exhaust holes and found that by moving the exhaust holes to the bottom of the ventilator mask,the CO2 residual concentration below the nostrils would be reduced to no more than 1%.This study established a near physiological computational model and provided a new method for the individualized design of the commercial ventilator mask.展开更多
The systemic administration of morphine affects ventilation via a mixture of central and peripheral actions. The aims of this study were to characterize the ventilatory responses elicited by a low dose of morphine in ...The systemic administration of morphine affects ventilation via a mixture of central and peripheral actions. The aims of this study were to characterize the ventilatory responses elicited by a low dose of morphine in conscious rats;to determine whether tolerance develops to these responses;and to determine the potential roles of peripheral μ-opioid receptors (μ-ORs) in these responses. Ventilatory parameters were monitored via unrestrained whole-body plethysmography. Conscious male Sprague-Dawley rats received an intravenous injection of vehicle or the peripherally-restricted μ-OR antagonist, naloxone methiodide (NLXmi), and then three successive injections of morphine (1 mg/kg) given 30 min apart. The first injection of morphine in vehicle-treated rats elicited an array of ventilatory excitant (i.e., increases in frequency of breathing, minute volume, respiratory drive, peak inspiratory and expiratory flows, accompanied by decreases in inspiratory time and end inspiratory pause) and inhibitory (i.e., a decrease in tidal volume and an increase in expiratory time) responses. Subsequent injections of morphine elicited progressively and substantially smaller responses. The pattern of ventilatory responses elicited by the first injection of morphine was substantially affected by pretreatment with NLXmi whereas NLXmi minimally affected the development of tolerance to these responses. Low-dose morphine elicits an array of ventilatory excitant and depressant effects in conscious rats that are subject to the development of tolerance. Many of these initial actions of morphine appear to involve activation of peripheral μ-ORs whereas the development of tolerance to these responses does not.展开更多
Resource-scarce regions with serious COVID-19 outbreaks do not have enough ventilators to support critically ill patients,and these shortages are especially devastating in developing countries.To help alleviate this s...Resource-scarce regions with serious COVID-19 outbreaks do not have enough ventilators to support critically ill patients,and these shortages are especially devastating in developing countries.To help alleviate this strain,we have designed and tested the accessible low-barrier in vivo-validated economical ventilator(ALIVE Vent),a COVID-19-inspired,cost-effective,open-source,in vivo-validated solution made from commercially available components.The ALIVE Vent operates using compressed oxygen and air to drive inspiration,while two solenoid valves ensure one-way flow and precise cycle timing.The device was functionally tested and profiled using a variable resistance and compliance artificial lung and validated in anesthetized large animals.Our functional test results revealed its effective operation under a wide variety of ventilation conditions defined by the American Association of Respiratory Care guidelines for ventilator stockpiling.The large animal test showed that our ventilator performed similarly if not better than a standard ventilator in maintaining optimal ventilation status.The FiO2,respiratory rate,inspiratory to expiratory time ratio,positive-end expiratory pressure,and peak inspiratory pressure were successfully maintained within normal,clinically validated ranges,and the animals were recovered without any complications.In regions with limited access to ventilators,the ALIVE Vent can help alleviate shortages,and we have ensured that all used materials are publicly available.While this pandemic has elucidated enormous global inequalities in healthcare,innovative,cost-effective solutions aimed at reducing socio-economic barriers,such as the ALIVE Vent,can help enable access to prompt healthcare and life saving technology on a global scale and beyond COVID-19.展开更多
Considering four different climate zones in China, an investigation on the choice of heat recovery ventilator for the buildings with little moisture emissions is carried out. The annual composition of energy consumpti...Considering four different climate zones in China, an investigation on the choice of heat recovery ventilator for the buildings with little moisture emissions is carried out. The annual composition of energy consumption of air intake for per unitary air ventilation flow rate is evaluated by employing the testing data of climatic parameters in eight selected cities. The analysis shows that the total heat recovery is suitable in a controlled ventilation system with air humidity controlled during heating period of all the climates. For the building without air humidity controlled in winter, the sensible heat recovery ventilators can be used in severe cold and cold regions, and total heat recovery systems are more suitable for energy saving in hot summer and cold winter and hot summer and warm winter regions.展开更多
BACKGROUND Prematurity in newborns is a condition that is associated with worse hospital outcomes when compared to birth to term.A preterm infant(PI)is classified when gestational age(GA)<37 wk.AIM To analyze progn...BACKGROUND Prematurity in newborns is a condition that is associated with worse hospital outcomes when compared to birth to term.A preterm infant(PI)is classified when gestational age(GA)<37 wk.AIM To analyze prognostic indicators related to the use of oxygen therapy,noninvasive ventilation(continuous positive airway pressure)and mechanical ventilation(MV)in PI.METHODS This is a retrospective cohort.The sample was composed of PIs from a private hospital in southern Brazil.We included neonates with GA<37 wk of gestation in the period of January 1,2018 to December 31,2018.For data collection,electronic records were used in the Tasy Philips^(TM)system,identifying the variables:maternal age,type of birth,prenatal information,GA,Apgar score,birth weight,neonatal morbidities,vital signs in the 1st hour at birth,need for oxygen therapy,continuous positive airway pressure and MV,hospitalization in the neonatal intensive care unit,length of stay and discharge or death.RESULTS In total,90 PI records were analyzed.The median(p25-p75)of GA was 34.0(31.9-35.4)wk,and there were 45(50%)males.The most common morbidity among PIs was the acute respiratory discomfort syndrome,requiring hospitalization in the neonatal intensive care unit in 76(84.4%)cases.The utilization rate of oxygen therapy,continuous positive airway pressure and MV was 12(13.3%),37(41.1%)and 13(14.4%),respectively.The median(p25-p75)length of stay was 12.0(5.0-22.2)d,with 10(11.1%)deaths.A statistical association was observed with the use of MV and GA<28 wk,lower maternal age,low birth weight,Apgar<8 and neonatal deaths.CONCLUSION The identification of factors related to the need for MV in prematurity may help in the indication of a qualified team and technologies to promptly meet the unforeseen events that may occur after birth.展开更多
BACKGROUND Patients with cancer have several risk factors for developing respiratory failure requiring mechanical ventilation(MV).The emergence of multidrug resistant bacteria(MDRB)has become a public health problem,c...BACKGROUND Patients with cancer have several risk factors for developing respiratory failure requiring mechanical ventilation(MV).The emergence of multidrug resistant bacteria(MDRB)has become a public health problem,creating a new burden on medical care in hospitals,particularly for patients admitted to the intensive care unit(ICU).AIM To describe risk factors for ventilator-acquired pneumonia(VAP)in patients with cancer and to evaluate the impact of MDRB.METHODS A retrospective study was performed from January 2016 to December 2018 at a cancer referral center in Mexico City,which included all patients who were admitted to the ICU and required MV≥48 h.They were classified as those who developed VAP versus those who did not;pathogens isolated,including MDRB.Clinical evolution at 60-d was assessed.Descriptive analysis was carried out;comparison was performed between VAP vs non-VAP and MDRB vs non-MDRB.RESULTS Two hundred sixty-three patients were included in the study;mean age was 51.9 years;52.1%were male;68.4%had solid tumors.There were 32 episodes of VAP with a rate of 12.2%;11.5 episodes/1000 ventilation-days.The most frequent bacteria isolated were the following:Klebsiella spp.[n=9,four were Extended-Spectrum Beta-Lactamase(ESBL)producers,one was Carbapenem-resistant(CR)];Escherichia coli(n=5,one was ESBL),and Pseudomonas aeruginosa(n=8,two were CR).One Methicillin-susceptible Staphylococcus aureus was identified.In multivariate analysis,the sole risk factor associated for VAP was length of ICU stay(OR=1.1;95%CI:1.03-1.17;P=0.003).Sixty-day mortality was 53%in VAP and 43%without VAP(P=0.342).There was not higher mortality in those patients with MDRB.CONCLUSION This study highlights the high percentage of Gram-negative bacteria,which allows the initiation of empiric antibiotic coverage for these pathogens.In this retrospective,single center,observational study,MDRB VAP was not directly linked to increased mortality at 60 days.展开更多
文摘The direct delivery of inhaled antibiotics to the respiratory tract has been a subject of enduring interest among medical practitioners and researchers due to the associated favorable pharmacokinetics.This interest has been particularly pronounced in the context of critically illpatients,wherehealthcare-associatedpulmonary infections represent a significant challenge,driving continued exploration of inhaled antibiotics for intubated patients.Recent high-level evidence has shown a very promising application in the field of ventilator-associated pneumonia (VAP) prevention.^([1]).
文摘Objective: To investigate the efficacy, safety and nursing improvement of noninvasive positive pressure ventilation (NPPV) in high-risk patients with acute respiratory failure after cardiac surgery. Methods: From September 2018 to October 2019, high-risk patients who may develop acute respiratory failure after cardiac surgery were selected and randomly divided into non-invasive ventilation group and conventional treatment group (control group). The reintubation rate, tracheotomy rate, fatality rate, 24 h intake and output, respiratory rate, arterial blood gas PaO2 and PaCO2 were compared between the two groups of patients;at the same time, the patient comfort and mask leakage after improved nursing technology were compared. Results: The preoperative and intraoperative conditions of the two groups of patients were basically similar, but the reintubation rate, tracheotomy rate, fatality rate, and respiratory rate of the patients in the preventive application of NPPV group were significantly lower than those of the control group, and the 24 h input and output and arterial blood gas PaO2 were also excellent in the control group. Conclusion: NPPV used prophylactically in high-risk patients after cardiac surgery can significantly reduce the re-intubation rate, improve patient outcomes, and is markedly more effective than the conventional treatment group.
文摘Objective: To investigate the effect of extracorporeal diaphragmatic pacing combined with noninvasive ventilators on the respiratory function and prognosis of chronic obstructive pulmonary disease (COPD) patients. Methods: A total of 50 COPD patients were selected between January 2023 to December 2023 and randomly grouped into an observation group and a control group, with 25 cases. The observation group was given extracorporeal diaphragm pacing combined with a noninvasive ventilator, while the control group was given a conventional treatment mode. After the treatment, the results of each index in the two groups were compared. Results: Compared with the diaphragm function indexes of the two groups, the data of the observation group were more dominant (P < 0.05). The rehospitalization rate of the observation group was lower than that of the control group (P < 0.05). The COPD assessment test (CAT) and mMRC (Modified Medical Research Council) Dyspnoea scale scores after treatment between the two groups were significantly different (P < 0.05). Compared with the control group, the lung function indexes of the observation group were more dominant (P < 0.05). Conclusion: Extracorporeal diaphragmatic pacing combined with a noninvasive ventilator promoted the improvement of the patient’s prognosis and improved their respiratory function.
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Mechanical ventilation is a specialized oxygen therapy and life support technology with significant importance for critically ill patients. In fact, 40%–66% of patients in the intensive care unit(ICU) require mechanical ventilation.^([1,2]) However, the mechanical ventilation can lead to ventilatorassociated lung injury(VALI),^([3]) ultimately resulting in difficulties in weaning from mechanical ventilation,prolonged hospital stays, and even increased mortality.
基金supported by the National Natural Science Foundation of China(81930049 and 82171926).
文摘A recent study on the rapid imaging of pulmonary ventilation using hyperpolarized ^(129)Xe MRI has demonstrated the ability to achieve isotropic 3D ventilation imaging with a spatial resolution of 3×3×3mm^(3) in humans,within an acquisition time of just 3.5 seconds(https://doi.org/10.1002/mrm.30120).
基金support by Technology R&D Program of China State Railway Group Co.,Ltd(Grant number N2022J013)the Hunan Provincial Innovation Foundation for Postgraduate(Grant number CX20220279)+1 种基金the Fundamental Research Funds for the Central Universities of Central South University(Grant number 2022ZZTS0193)China Scholarship Council(202106370112)。
文摘During the train meeting events,train equipment compartments are exposed to the worst pressure changes,potentially affecting the ventilation performance of equipment,particularly for electrical facilities equipped with independent air ducts.In this paper,a two-step method is used for numerical computation:(1)obtaining the temporal and spatial transient node data of the flow field sections during the train-passing simulation and(2)using the data as the input data for the equipment compartment simulation.In addition,this paper also compares the difference in equipment ventilation between the single-train and trainpassing scenarios in real vehicle tests.The results indicate that the primary factors influencing ventilation effectiveness are the aerodynamic compression and deceleration of airflow induced by the other train's nose,as well as the instability of the external flow field in the wake of the other train.During train crossing,the air is forced into the air duct,with a maximum ratio of the airflow in-duct to the airflow out-duct reaching 3.2.The average mass flow falls below the rated mass flow for the converter.Compared to the rated air volume of converter,the maximum suppression rates obtained from testing and simulation are-24.5%and-16.8%,respectively.Compared to the single-train operation,the maximum suppression rates obtained from testing and simulation are-15%and-18%,respectively.These findings provide valuable insights into the design and operation of high-speed trains.
基金Funding Statement:This research was conducted as part of the Tech4You Project“Technologies for climate change adaptation and quality of life improvement”,n.ECS0000009,CUP H23C22000370006,Italian PNRR,Mission 4,Component 2,Investment 1.5 funded by the European Union-NextGenerationEU.
文摘Indoor air quality(IAQ)is often overlooked,yet a poorly maintained environment can lead to significant health issues and reduced concentration and productivity in work or educational settings.This study presents an innovative control system for mechanical ventilation specifically designed for university classrooms,with the dual goal of enhancing IAQ and increasing energy efficiency.Two classrooms with distinct construction characteristics were analyzed:one with exterior walls and windows,and the other completely underground.For each classroom,a model was developed using DesignBuilder software,which was calibrated with experimental data regarding CO_(2) concentration,temperature,and relative humidity levels.The proposed ventilation system operates based on CO_(2) concentration,relative humidity,and potential for free heating and cooling.In addition,the analysis was conducted for other locations,demonstrating consistent energy savings across different climates and environments,always showing an annual reduction in energy consumption.Results demonstrate that mechanical ventilation,when integrated with heat recovery and free cooling strategies,significantly reduces energy consumption by up to 25%,while also maintaining optimal CO_(2) levels to enhance comfort and air quality.These findings emphasize the essential need for well-designed mechanical ventilation systems to ensure both psychophysical well-being and IAQ in enclosed spaces,particularly in environments intended for extended occupancy,such as classrooms.Furthermore,this approach has broad applicability,as it could be adapted to various building types,thereby contributing to sustainable energy management practices and promoting healthier indoor spaces.This study serves as a model for future designs aiming to balance energy efficiency with indoor air quality,especially relevant in the post-COVID era,where the importance of indoor air quality has become more widely recognized.
文摘BACKGROUND:We sought to evaluate the risk factors for developing ventilator-associated pneumonia(VAP)and whether the location of intubation posed a risk in trauma patients.METHODS:Data were retrospectively reviewed for adult trauma patients requiring intubation for>48 hours,admitted between 2010 and 2013.Patients’demographics,clinical presentations and outcomes were compared according to intubation location(prehospital intubation[PHI]vs.trauma room[TRI])and presence vs.absence of VAP.Multivariate regression analysis was performed to identify predictors of VAP.RESULTS:Of 471 intubated patients,332 patients met the inclusion criteria(124 had PHI and208 had TRI)with a mean age of 30.7±14.8 years.PHI group had lower GCS(P=0.001),respiratory rate(P=0.001),and higher frequency of head(P=0.02)and chest injuries(P=0.04).The rate of VAP in PHI group was comparable to the TRI group(P=0.60).Patients who developed VAP were 6 years older,had significantly lower GCS and higher ISS,head AIS,and higher rates of polytrauma.The overall mortality was 7.5%,and was not associated with intubation location or pneumonia rates.In the early-VAP group,gram-positive pathogens were more common,while gram-negative microorganisms were more frequently encountered in the late VAP group.Logistic regression analysis and modeling showed that the impact of the location of intubation in predicting the risk of VAP appeared only when chest injury was included in the models.CONCLUSION:In trauma,the risk of developing VAP is multifactorial.However,the location of intubation and presence of chest injury could play an important role.
文摘AIM: To determine the incidence, etiology, risk factors and outcome of ventilator-associated pneumonia(VAP) in patients undergoing orthotopic liver transplantation(OLT).METHODS: This retrospective study considered 242 patients undergoing deceased donor OLT. VAP was diagnosed according to clinical and microbiological criteria. RESULTS: VAP occurred in 18(7.4%) patients, with an incidence of 10 per 1000 d of mechanical ventilation(MV). Isolated bacterial etiologic agents were mainly Enterobacteriaceae(79%). Univariate logistic analysis showed that model for end-stage liver disease(MELD) score, pre-operative hospitalization, treatment with terlipressin, Child-Turcotte-Pugh score, days of MV and red cell transfusion were risk factors for VAP. Multivariateanalysis, considering significant risk factors in univariate analysis, demonstrated that pneumonia was strongly associated with terlipressin usage, pre-operative hospitalization, days of MV and red cell transfusion. Mortality rate was 22% in the VAP group vs 4% in the group without VAP. CONCLUSION: Our data suggest that VAP is an important cause of nosocomial infection during postoperative period in OLT patients. MELD score was a significant risk factor in univariate analysis. Multiple transfusions, treatment with terlipressin, preoperative hospitalization rather than called to the hospital while at home and days of MV constitute important risk factors for VAP development.
基金supported by the National Natural Science Foundation of China(grant number 81501654)Natural Science Foundation of Shanghai(grant number 14ZR1433700)
文摘BACKGROUND: Data on the mechanical ventilation(MV) characteristics and radiologic features for the cases with H7 N9-induced ARDS were still lacking.METHODS: We describe the MV characteristics and radiologic features of adult patients with ARDS due to microbiologically confirmed H7 N9 admitted to our ICU over a 3-month period.RESULTS: Eight patients(mean age 57.38±16.75; 5 male) were diagnosed with H7 N9 in the first quarter of 2014. All developed respiratory failure complicated by acute respiratory distress syndrome(ARDS), which required MV in ICU. The baseline APACHE II and SOFA score was 11.77±6.32 and 7.71±3.12. The overall CT scores of the patients was 247.68±34.28 and the range of CT scores was 196.3–294.7. The average MV days was 14.63±6.14, and 4 patients required additional rescue therapies for refractory hypoxemia. Despite these measures, 3 patients died.CONCLUSION: In H7 N9-infected patients with ARDS, low tidal volume strategy was the conventional mode. RM as one of rescue therapies to refractory hypoxemia in these patients with serious architectural distortion and high CT scores, which could cause further lung damage, may induce bad outcomes and requires serious consideration. Prone ventilation may improve mortality, and should be performed at the early stage of the disease, not as a rescue therapy.
文摘Objective： Ventilator associated pneumonia （VAP） has been shown to be associated with significant morbidity and mortality（ Chastre and Fagon, 2002; klompas, 2007） among mechanically venti- lated patients in the intensive care unit （ICU）, with the incidence ranging from 9% to 27% ; crude mortality ranges from 25% to 50%.1-3 A meta-analysis of published studies was undertaken to combine information regarding the effect of subglottic secretion drainage （SSD） on the incidence of ventilated associated pneumonia in adult ICU patients. Methods： Reports of studies on SSD were identified by searching the PUBMED, EMBASE, and COCHRANCE LIBRARY databases （December 30, 2010）. Randomized trials of SSD compared to usual care in adult mechanically ventilated ICU patients were included in this meta-analysis. Results： Ten RCTs with 2,314 patients were identified. SSD significantly reduced the incidence of VAP [ relative risk （RR） =0.52, 95% confidence interval （C/）： 0.42-0.64, P〈0.000 01]. When SSD was compared with the control groups, the overall RR for ICU mortality was 1.00 （95% CI, 0.84-1.19） and for hospital mortality was 0.95 （95% CI, 0. 80-1.13）. Overall, the subglottic drainage effect on the days of mechanical ventilation was -1.52 days （95% CI, -2.94 to -0.11） and on the ICU length of stay （LOS） was -0.81days （95% CI, -2.33 to -0.7）. Conclusions： In this meta-analysis, when an endotracheal tube （ETT） with SSD was compared with an ETT without SSD, there was a highly significant reduction in the VAP rate of approxi- mately 50%. Time on mechanical ventilation （MV） and the ICU LOS may be reduced, but no reduction in ICU or hospital mortality has been observed in published trials,
文摘Expiratory flow limitation(EFL), that is the inability of expiratory flow to increase in spite of an increase of the driving pressure, is a common and unrecognized occurrence during mechanical ventilation in a variety of intensive care unit conditions. Recent evidence suggests that the presence of EFL is associated with an increase in mortality, at least in acute respiratory distress syndrome(ARDS) patients, and in pulmonary complications in patients undergoing surgery. EFL is a major cause of intrinsic positive end-expiratory pressure(PEEPi), which in ARDS patients is heterogeneously distributed, with a consequent increase of ventilation/perfusion mismatch and reduction of arterial oxygenation. Airway collapse is frequently concomitant to the presence of EFL.When airways close and reopen during tidal ventilation, abnormally high stresses are generated that can damage the bronchiolar epithelium and uncouple small airways from the alveolar septa, possibly generating the small airways abnormalities detected at autopsy in ARDS. Finally, the high stresses and airway distortion generated downstream the choke points may contribute to parenchymal injury, but this possibility is still unproven. PEEP application can abolish EFL, decrease PEEPi heterogeneity, and limit recruitment/derecruitment.Whether increasing PEEP up to EFL disappearance is a useful criterion for PEEP titration can only be determined by future studies.
基金We acknowledge the National Natural Science Foundation of China for supporting the project via the grant number 11472062 and 11002034.
文摘OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in sleep.Currently,the optimal treatment is to apply CPAP(Continuous Positive Airway Pressure)ventilation on the upper airway of the patient through a household respiratory machine.However,if the ventilator mask is designed improperly,it might cause the residue and repeated inhalation of CO2,which will exert an adverse impact on the therapeutic effect.Present research numerically analyzed the CO2 transportation inside a commercial ventilator mask(Mirage SoftGel,ResMed,Australia)based on the reconstructed 3D numerical model of a volunteer's face and performed the improved design of the ventilator mask in terms of the CO2 residual concentration below the nostrils.The fluid dynamic analyses showed that at the end time of expiratory,the CO2 residual concentration below the nostrils is close to 4%.To improve the therapeutic effect,we changed the position of the exhaust holes and found that by moving the exhaust holes to the bottom of the ventilator mask,the CO2 residual concentration below the nostrils would be reduced to no more than 1%.This study established a near physiological computational model and provided a new method for the individualized design of the commercial ventilator mask.
文摘The systemic administration of morphine affects ventilation via a mixture of central and peripheral actions. The aims of this study were to characterize the ventilatory responses elicited by a low dose of morphine in conscious rats;to determine whether tolerance develops to these responses;and to determine the potential roles of peripheral μ-opioid receptors (μ-ORs) in these responses. Ventilatory parameters were monitored via unrestrained whole-body plethysmography. Conscious male Sprague-Dawley rats received an intravenous injection of vehicle or the peripherally-restricted μ-OR antagonist, naloxone methiodide (NLXmi), and then three successive injections of morphine (1 mg/kg) given 30 min apart. The first injection of morphine in vehicle-treated rats elicited an array of ventilatory excitant (i.e., increases in frequency of breathing, minute volume, respiratory drive, peak inspiratory and expiratory flows, accompanied by decreases in inspiratory time and end inspiratory pause) and inhibitory (i.e., a decrease in tidal volume and an increase in expiratory time) responses. Subsequent injections of morphine elicited progressively and substantially smaller responses. The pattern of ventilatory responses elicited by the first injection of morphine was substantially affected by pretreatment with NLXmi whereas NLXmi minimally affected the development of tolerance to these responses. Low-dose morphine elicits an array of ventilatory excitant and depressant effects in conscious rats that are subject to the development of tolerance. Many of these initial actions of morphine appear to involve activation of peripheral μ-ORs whereas the development of tolerance to these responses does not.
基金the National Institutes of Health(NIH R01 HL089315-01 and NIH R01 HL152155,YJW)the Thoracic Surgery Foundation Resident Research Fellowship(YZ)the National Science Foundation Graduate Research Fellowship Program(AMI).
文摘Resource-scarce regions with serious COVID-19 outbreaks do not have enough ventilators to support critically ill patients,and these shortages are especially devastating in developing countries.To help alleviate this strain,we have designed and tested the accessible low-barrier in vivo-validated economical ventilator(ALIVE Vent),a COVID-19-inspired,cost-effective,open-source,in vivo-validated solution made from commercially available components.The ALIVE Vent operates using compressed oxygen and air to drive inspiration,while two solenoid valves ensure one-way flow and precise cycle timing.The device was functionally tested and profiled using a variable resistance and compliance artificial lung and validated in anesthetized large animals.Our functional test results revealed its effective operation under a wide variety of ventilation conditions defined by the American Association of Respiratory Care guidelines for ventilator stockpiling.The large animal test showed that our ventilator performed similarly if not better than a standard ventilator in maintaining optimal ventilation status.The FiO2,respiratory rate,inspiratory to expiratory time ratio,positive-end expiratory pressure,and peak inspiratory pressure were successfully maintained within normal,clinically validated ranges,and the animals were recovered without any complications.In regions with limited access to ventilators,the ALIVE Vent can help alleviate shortages,and we have ensured that all used materials are publicly available.While this pandemic has elucidated enormous global inequalities in healthcare,innovative,cost-effective solutions aimed at reducing socio-economic barriers,such as the ALIVE Vent,can help enable access to prompt healthcare and life saving technology on a global scale and beyond COVID-19.
基金National Natural Science Foundation of China(Grant No50578034)Shanghai Educational Development Foundationtitled"Shuguang Project"(Grant NO03SG30)
文摘Considering four different climate zones in China, an investigation on the choice of heat recovery ventilator for the buildings with little moisture emissions is carried out. The annual composition of energy consumption of air intake for per unitary air ventilation flow rate is evaluated by employing the testing data of climatic parameters in eight selected cities. The analysis shows that the total heat recovery is suitable in a controlled ventilation system with air humidity controlled during heating period of all the climates. For the building without air humidity controlled in winter, the sensible heat recovery ventilators can be used in severe cold and cold regions, and total heat recovery systems are more suitable for energy saving in hot summer and cold winter and hot summer and warm winter regions.
文摘BACKGROUND Prematurity in newborns is a condition that is associated with worse hospital outcomes when compared to birth to term.A preterm infant(PI)is classified when gestational age(GA)<37 wk.AIM To analyze prognostic indicators related to the use of oxygen therapy,noninvasive ventilation(continuous positive airway pressure)and mechanical ventilation(MV)in PI.METHODS This is a retrospective cohort.The sample was composed of PIs from a private hospital in southern Brazil.We included neonates with GA<37 wk of gestation in the period of January 1,2018 to December 31,2018.For data collection,electronic records were used in the Tasy Philips^(TM)system,identifying the variables:maternal age,type of birth,prenatal information,GA,Apgar score,birth weight,neonatal morbidities,vital signs in the 1st hour at birth,need for oxygen therapy,continuous positive airway pressure and MV,hospitalization in the neonatal intensive care unit,length of stay and discharge or death.RESULTS In total,90 PI records were analyzed.The median(p25-p75)of GA was 34.0(31.9-35.4)wk,and there were 45(50%)males.The most common morbidity among PIs was the acute respiratory discomfort syndrome,requiring hospitalization in the neonatal intensive care unit in 76(84.4%)cases.The utilization rate of oxygen therapy,continuous positive airway pressure and MV was 12(13.3%),37(41.1%)and 13(14.4%),respectively.The median(p25-p75)length of stay was 12.0(5.0-22.2)d,with 10(11.1%)deaths.A statistical association was observed with the use of MV and GA<28 wk,lower maternal age,low birth weight,Apgar<8 and neonatal deaths.CONCLUSION The identification of factors related to the need for MV in prematurity may help in the indication of a qualified team and technologies to promptly meet the unforeseen events that may occur after birth.
文摘BACKGROUND Patients with cancer have several risk factors for developing respiratory failure requiring mechanical ventilation(MV).The emergence of multidrug resistant bacteria(MDRB)has become a public health problem,creating a new burden on medical care in hospitals,particularly for patients admitted to the intensive care unit(ICU).AIM To describe risk factors for ventilator-acquired pneumonia(VAP)in patients with cancer and to evaluate the impact of MDRB.METHODS A retrospective study was performed from January 2016 to December 2018 at a cancer referral center in Mexico City,which included all patients who were admitted to the ICU and required MV≥48 h.They were classified as those who developed VAP versus those who did not;pathogens isolated,including MDRB.Clinical evolution at 60-d was assessed.Descriptive analysis was carried out;comparison was performed between VAP vs non-VAP and MDRB vs non-MDRB.RESULTS Two hundred sixty-three patients were included in the study;mean age was 51.9 years;52.1%were male;68.4%had solid tumors.There were 32 episodes of VAP with a rate of 12.2%;11.5 episodes/1000 ventilation-days.The most frequent bacteria isolated were the following:Klebsiella spp.[n=9,four were Extended-Spectrum Beta-Lactamase(ESBL)producers,one was Carbapenem-resistant(CR)];Escherichia coli(n=5,one was ESBL),and Pseudomonas aeruginosa(n=8,two were CR).One Methicillin-susceptible Staphylococcus aureus was identified.In multivariate analysis,the sole risk factor associated for VAP was length of ICU stay(OR=1.1;95%CI:1.03-1.17;P=0.003).Sixty-day mortality was 53%in VAP and 43%without VAP(P=0.342).There was not higher mortality in those patients with MDRB.CONCLUSION This study highlights the high percentage of Gram-negative bacteria,which allows the initiation of empiric antibiotic coverage for these pathogens.In this retrospective,single center,observational study,MDRB VAP was not directly linked to increased mortality at 60 days.
