Prevention of ventilator-associated pneumonia with inhaled antibiotics

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]).

Comparison of the Use of Conventional and Antibiotic-Coated Tracheal Tubes and EVAC on the Incidence of Ventilator-Associated Pneumonia (VAP)

Ventilator-associated pneumonia (VAP) is one of the most important hospital infections in hospitalized patients, which is associated with increased mortality and patient costs. The tracheal tube itself seems to be a major risk factor for VAP. Contaminated secretions pass through the endotracheal tube and reach the lungs. Also, bacteria form a bacterial biofilm on the tracheal tube and are transferred from there to the lungs. Different tracheal tube designs have been produced to overcome these cases. The purpose of this study is to investigate the effect of an Evac tracheal tube covered with antibiotics and normal on the incidence of pneumonia caused by the ventilator. Research method: 180 patients were randomly intubated in three groups of 60 people with three types of tracheal tubes, Evac and Bactiguard. Clinical examinations, endotracheal tube aspiration culture, and chest radiography were obtained from the patients and the incidence of VAP was calculated based on the CPIS standard. The relationship between the type of endotracheal tube and the incidence of VAP and the length of stay in the intensive care unit (ICU) and being discharged alive from the ICU were investigated. Findings and conclusions: The average incidence of VAP for the group of patients intubated with a conventional tracheal tube was 50%, EVAC was 45% and Bactiguard was 40%. The results showed that there is no significant relationship between the incidence of ventilator-induced pneumonia and the type of tracheal tube. The incidence of ventilator-induced pneumonia was not significantly reduced by suctioning subglottic secretions and Bactiguard tracheal tubes. It seems that using one method alone is not effective in reducing ventilator-induced pneumonia.

Risk factors for ventilator-associated pneumonia in trauma patients:A descriptive analysis

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.

Ventilator-associated pneumonia in patients with cancer: Impact of multidrug resistant bacteria

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.

Epidemiological characteristics of ventilator-associated pneumonia in neurosurgery:A 10-year surveillance study in a Chinese tertiary hospital

Background Ventilator-associated pneumonia(VAP)is a significant and common health concern.The epidemiological landscape of VAP is poorly understood in neurosurgery patients.This study aimed to explore the epidemiology of VAP in this population and devise targeted surveillance,treatment,and control efforts.Methods A 10-year retrospective study spanning 2011 to 2020 was performed in a large Chinese tertiary hospital.Surveillance data was collected from neurosurgical patients and analyzed to map the demographic and clinical characteristics of VAP and describe the distribution and antimicrobial resistance profile of leading pathogens.Risk factors associated with the presence of VAP were explored using boosted regression tree(BRT)models.Results Three hundred ten VAP patients were identified.The 10-year incidence of VAP was 16.21 per 1000 ventilation days.All-cause mortality was 6.1%.The prevalence of gram-negative bacteria,fungi,and gram-positive bacteria among the 357 organisms isolated from VAP patients was 86.0%,7.6%,and 6.4%,respectively;most were multidrug-resistant organisms.Acinetobacter baumannii,Klebsiella pneumoniae,and Pseudomonas aeruginosa were the most common pathogens.The prevalence of carbapenem-resistant A.baumannii,P.aeruginosa,and K.pneumoniae was high and increased over time in the study period.The BRT models revealed that VAP was associated with number of days of ventilator use(relative contribution,47.84±7.25),Glasgow Coma Scale score(relative contribution,24.72±5.67),and tracheotomy(relative contribution,21.50±2.69).Conclusions Our findings provide a better understanding of the epidemiology of VAP and its risk factors in neurosurgery patients.

Ventilator associated pneumonia following liver transplantation:Etiology,risk factors and outcome

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.

Subglottic Secretion Drainage for Preventing Ventilator Associated Pneumonia: A Meta-analysis

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,

Infection Route Analysis of Ventilator Associated Pneumonia

Objective A prospective study was conducted in a tertiary care center to identify the risk factors of ventilator associated pneumonia(VAP) through phenotypic and molecular biological methods. Methods The patients who were mechanically ventilated in the respiratory intensive care unit(RICU) and the neurological internal intensive care unit(NICU) were enrolled in our study, and samples were collected from the lower respiratory tract, oropharynx and stomach. Other samples, including the environmental air, swabs of nurses' hands, subglottic secretion and ventilator circuit, were also collected. Microorganisms in the collected samples were recovered and identified at species level by biochemical detection. Genetic relationship of dominant species was further characterized by pulsed field gel electrophoresis(PFGE). Results Out of 48 enrolled patients, 22 cases developed VAP and bacterial cultures were recovered from the lower respiratory tract samples of 14 cases. The average hospitalization time with VAP was significantly longer than that of patients without VAP(P < 0.05). Among the recovered bacteria cultures, multidrug-resistant Pseudomonas aeruginosa and Stenotrophomonas maltophilia were dominant. It was more likely that subglottic secretion and gastric juice samples contained the same isolates as recovered in the lower respiratory tract by PFGE analysis. Conclusions Mechanical ventilation in RICU and NICU was a high risk factor for VAP development. Special emphasis of VAP prophylaxis should be paid on subglottic secretion and gastric juice reflux.

The Diagnostic and Prognostic Value of Serum Procalcitonin among Ventilator Associated Pneumonia Patients

Ventilator-associated pneumonia (VAP) is a complication in as many as 28% of patients who receive mechanical ventilation. Studies have consistently shown that a delay in diagnosis and treatment increases the mortality risk. The aim of this work was to clarify the role of the serum procalcitonin (PCT) in the diagnosis and the prognosis of ventilator associated pneumonia. Methods: Forty two VAP patients, 20 non VAP-ICU (on mechanical ventilation) admitted patients and 20 healthy control subjects of similar age and sex were included in the study. PCT levels in serum samples were measured in all subjects. Results: There was a highly statistically significant difference (p value 0.001) between VAP patients on one side and non VAP-ICU patients and healthy control subjects on the other side regarding the mean values of PCT. Also, the mean values of PCT were statistically significantly higher (p 0.001) among died VAP group than the survivor VAP group. There was a statistically positive correlation (p = 0.449), CRIP (R = 0.403) and SOFA (R = 0.437)) and initial PCT serum levels. Conclusions: This study found that the increased PCT serum level is an important diagnostic tool for VAP and the PCT serum levels can predict the outcome of VAP patients. We recommend other larger studies to augment our findings.

Ventilator Associated Pneumonia in an Intensive Care Unit

The aim of this prospective study was to evaluate the incidence, etiologic agents and mortality rate of ventilator-associated pneumonia (VAP). In a six-month period, cases who were 18 years or older, dependent on mechanical ventilator for more than 3 days and without pulmonary infection on first admission were included in this study. In all cases, body temperature recordings, blood and urine culture, microbiological analyses of endotracheal aspirates, and chest X-rays were obtained and used to identify VAP. Apache II scores on admission, duration of mechanical ventilation, length of intensive care unit (ICU) stay and mortality were recorded. This study included 45 cases and 22 developed VAP (48%). The incidence of VAP was 25.34 per 1000 ventilator days. Univariate analyses showed that duration of mechanical ventilation, length of ICU stay, coma and tracheotomy were associated with the development of VAP. The mortality rate of cases with VAP (72.7%) was significantly higher than cases without VAP (39.1%). The most frequent microorganisms were Acinetobacter spp., Pseudomonas aeruginosa and Klebsiella pneumoniae. In our study, VAP was a very common and important complication of mechanical ventilation and mortality was very high. To reduce mortality, minimize morbidity, shorten the length of stay, and reduce costs, defined risk factors for VAP should be recognized and an effective infection control program for the prevention of VAP should be implemented. Surveillance results should be evaluated regularly and necessary precautions should be taken.

Pseudomonas aeruginosa ventilator associated pneumonia: improved outcomes with earlier follow-up

It is not clear what is the appropriate timing to follow-up patients with ventilator-associated pneumonia (VAP) and Clinical Pulmonary Infe- ction Score >6 between days 3-5 of an appro- priate antibiotic treatment. We studied 122 patients with Pseudomonas aeruginosa VAP. A follow-up respiratory sample was collected on days three or five ( “day-three” and “day-five” group ) and treatment was modified 48h later. Molecular typing identified super-infections or persistence. For serial data another respiratory sample was collected, on day three from the “day-five” group and on day five from the “day-three” group. Sixty patients, in the “day- three” group compared to 62 in the “day-five” group, had reduced fourteen-day mortality ( 18.3% and 38.7%;p=0.01 ) and fewer days in intensive care unit (17.2 ± 4.3 compared to 27.3 ± 4.7, p6, improved fourteen-day mortality and shorter duration of stay in health-care facilities were observed with earlier follow-up.

Prevention of ventilator-associated pneumonia through care bundles:A systematic review and meta-analysis

Background Ventilator-associated pneumonia(VAP)represents a common hospital-acquired infection among mechanically ventilated patients.We summarized evidence concerning ventilator care bundles to prevent VAP.Methods A systematic review and meta-analysis were performed.Randomized controlled trials and controlled observational studies of adults undergoing mechanical ventilation(MV)for at least 48 h were considered for inclusion.Outcomes of interest were the number of VAP episodes,duration of MV,hospital and intensive care unit(ICU)length of stay,and mortality.A systematic search was conducted in the MEDLINE,the Cochrane Library,and the Web of Science between 1985 and 2022.Results are reported as odds ratio(OR)or mean difference(MD)with 95%confidence intervals(CI).The PROSPERO registration number is CRD42022341780.Results Thirty-six studies including 116,873 MV participants met the inclusion criteria.A total of 84,031 participants underwent care bundles for VAP prevention.The most reported component of the ventilator bundle was head-of-bed elevation(n=83,146),followed by oral care(n=80,787).A reduction in the number of VAP episodes was observed among those receiving ventilator care bundles,compared with the non-care bundle group(OR=0.42,95%CI:0.33,0.54).Additionally,the implementation of care bundles decreased the duration of MV(MD=−0.59,95%CI:−1.03,−0.15)and hospital length of stay(MD=−1.24,95%CI:−2.30,−0.18)in studies where educational activities were part of the bundle.Data regarding mortality were inconclusive.Conclusions The implementation of ventilator care bundles reduced the number of VAP episodes and the duration of MV in adult ICUs.Their application in combination with educational activities seemed to improve clinical outcomes.

Effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia

Objective: To discuss the effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia. Methods: A total of 68 patients with COPD complicated by severe pneumonia who were treated in the hospital between November 2015 and April 2017 were collected, retrospectively analyzed and then divided into the group A (n=35) who received noninvasive positive pressure ventilation and the group B (n=33) who received lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation. The differences in arterial blood gas and serum index levels were compared between the two groups before and after treatment. Results: Before treatment, there was no statistically significant difference in arterial blood gas index levels as well as serum contents of inflammatory mediators, stress hormones and myocardial enzyme spectrum indexes between the two groups. After treatment, arterial blood gas indexes PH and PaO2 levels of group B were higher than those of group A;serum inflammatory mediators HMGB1, PCT and hs-CRP contents were lower than those of group A;serum stress hormones Cor, AngⅠ and AngⅡcontents were lower than those of group A;serum myocardial enzyme spectrum indexesα-HBDH and cTn-Ⅰ contents were lower than those of group A. Conclusion: Lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation can effectively optimize the arterial blood gas levels, reduce systemic inflammatory stress state and protect the myocardial function of patients with COPD complicated by severe pneumonia.

Clinical efficacy of mask continuous positive airway pressure mechanical ventilation in children with severe pneumonia

Objective: To investigate the clinical effects of the mask continuous positive airway pressure (CPAP) mechanical ventilation in children with severe pneumonia. Methods: A total of 100 cases of children with severe pneumonia were randomly divided into two groups, study group with 50 children and control group with 50 children. These 100 children were given comprehensive treatment measures: treatment of anti-infection, anti-respiratory failure, anti-heart failure (if necessary), relieving cough and reducing sputum, aerosol inhalation, limited fluid volume, nutrition support etc. Children in the study group were added mask continuous positive airway pressure mechanical ventilation (CPAP). Children in the control group were added ordinary mask oxygen inhalation. Investigated and checked the treatment effect in these two groups. Results: After treatment, SaO2, PaO2 in both two groups were showed significantly higher than before the treatment. PaO2 of the study group is obviously higher than the control group. The oxygen inhalation time of the study group was obviously lesser than the control group. The total effective rate of the study group was significantly higher than the control group which was 96.0% vs 66.0%. Conclusion: The mask continuous positive airway pressure (CPAP) mechanical ventilation can significantly improve the related symptoms and blood gas status of the children with severe pneumonia, shorten the oxygen inhalation time and had remarkable effect.

Risk factors for ventilator-associated pneumonia among patients undergoing major oncological surgery for head and neck cancer

Patients undergoing major oncological surgery for head and neck cancer （SHNC） have a particularly high risk of nosocomial infections. We aimed to identify risk factors for ventilator-associated pneumonia （VAP） in patients undergoing SHNC. The study included 465 patients who underwent SHNC between June 2011 and June 2014. The rate of VAP, risk factors for VAP, and biological aspects of VAP were retrospectively evaluated. The incidence of VAP was 19.6~0 （n = 95） in patients who required more than 48 h of mechanical ventilation. Staphylococcus （37.7%）, Enterobacteriaceae （32.1%）, Pseudomonas （20.8%）, and Haemophilus （16.9~） were the major bacterial species that caused VAP. The independent risk factors for VAP were advanced age, current smoking status, chronic obstructive pulmonary disease, and a higher simplified acute physiology score system II upon admission. Tracheostomy was an independent protective factor for VAP. The median length of stay in the ICU for patients who did or did not develop VAP was 8.0 and 6.5 days, respectively （P = 0.006）. Mortality among patients who did or did not develop VAP was 16.8% and 8.4%, respectively （P 〈 0.001）. The potential economic impact of VAP was high because of the significantly extended duration of ventilation. A predictive regression model was developed with a sensitivity of 95.3% and a specificity of 69.4%. VAP is common in patients who are undergoing SHNC and who require more than 48 h of mechanical ventilation. Therefore, innovative preventive measures should be developed and applied in this high-risk population.

Outcomes and risk factors of ventilator-associated pneumonia in neonates

Background:Ventilator-associated pneumonia (VAP) in neonates has been associated with high mortality and poor outcome.This study aimed to compare the incidence,risk factors,and outcomes of VAP and nonVAP conditions in neonates.Methods:We performed a prospective cohort study in a neonatal intensive care unit (NICU) in Thailand from January 2014 to December 2014.All neonatal patients who were ventilated more than 48 hours were enrolled.Results:There were 128 enrolled patients.The median (inter quartile range) gestational age and birthweight were 35 (30.2,37.8) weeks and 2380 (1323.8,3020.0) g.There were 17 VAP patients (19 episodes) and 111 non-VAP ones.The VAP rate was 13.3% or 10.1 per 1000 ventilator days.According to the multivariate analysis,a birthweight less than 750 g [adjusted odds ratio (aOR)=10.75,95% confidence interval (CI)=2.35-49.16;P=0.002] and sedative medication use (aOR=4.00,95% CI=1.23-12.50;P=0.021)were independent risk factors for VAP.Compared with the non-VAP group,the median difference in the VAP group yielded a significantly longer duration of NICU stay (18 days,P=0.001),total length of hospital stay (16 days,P=0.002) and higher hospital costs ($5113,P=0.001).The inhospital mortality rate in the VAP and non-VAP groups was 17.6% and 15.3% (P=0.73),respectively.Conclusions:A neonatal birthweight less than 750 g and sedative medication use were independent risk factors for VAP.Our VAP patients experienced a longer duration of both NICU and hospital stay,and incurred higher hospitalization costs.

Antibiotics De-Escalation in the Treatment of Ventilator-Associated Pneumonia in Trauma Patients： A Retrospective Study on Propensity Score Matching Method

Background： Antimicrobial de-escalation refers to starting the antimicrobial treatment with broad-spectrum antibiotics, followed by narrowing the drug spectrum according to culture results. The present study evaluated the effect of de-escalation on ventilator-associated pneumonia （VAP） in trauma patients. Methods： This retrospective study was conducted on trauma patients with VAP, who received de-escalation therapy （de-escalation group） or non-de-escalation therapy （non-de-escalation group）. Propensity score matching method was used to balance the baseline characteristics between both groups. The 28-day mortality, length of hospitalization and Intensive Care Unit stay, and expense of antibiotics and hospitalization between both groups were compared. Multivariable analysis explored the factors that influenced the 28-day mortality and implementation of de-escalation. Results： Among the 156 patients, 62 patients received de-escalation therapy and 94 patients received non-de-escalation therapy. No significant difference was observed in 28-day mortality between both groups （28.6% vs. 23.8%, P = 0.620）. The duration of antibiotics treatment in the de-escalation group was shorter than that in the non-de-escalation group （11 [8-13] vs. 14 [8-19] days, P = 0.045）. The expenses of antibiotics and hospitalization in de-escalation group were significantly lower than that in the non-de-escalation group （6430 ± 2730 vs. 7618 ± 2568 RMB Yuan, P = 0.043 and 19,173 ± 16,861 vs. 24,184 ± 12,039 RMB Yuan, P = 0.024, respectively）. Multivariate analysis showed that high Acute Physiology and Chronic Health Evaluation Ⅱ （APACHE Ⅱ） score, high injury severity score, multi-drug resistant （MDR） infection, and inappropriate initial antibiotics were associated with patients＇ 28-day mortality, while high APACHEⅡ score, MDR infection and inappropriate initial antibiotics were independent factors that prevented the implementation of de-escalation. Conclusions： De-escalation strategy in the treatment of trauma patients with VAP could reduce the duration of antibiotics treatments and expense of hospitalization, without increasing the 28-day mortality and MDR infection.

Microscopic examination of intracellular organisms in bronchoalveolar lavage fluid for the diagnosis of ventilator-associated pneumonia：a prospective multi-center study

Background The presence of intracellular organisms （ICOs） in polymorphonuclear leukocytes obtained from bronchoalveolar lavage fluid （BALF） is a possible method for rapid diagnosis of ventilator-associated pneumonia （VAP）.However,the validity of this diagnostic method remains controversial and the diagnostic thresholds reported by investigators were different.Our objective was to evaluate the accuracy of quantification of ICOs in BALF for the diagnosis of VAP,and to detect the best cutoff percentage of PMNs containing ICOs （PIC） in the microscopic examination of BALF for the diagnosis of VAP.Methods This was a prospective multi-center study conducted in 4 ICUs in Wuhan,China,which involved 181 patients suspected of first episode of VAP.BALF was obtained from all enrolled patients.The BALF samples underwent quantitative culture,cytological and bacteriological analysis to detect the culture results,PIC values and the morphological features of microorganisms.Definite diagnosis of VAP was based on pre-set criteria.The receiver-operating characteristic curve was used to detect the best cutoff point for PIG to diagnose VAP,and the diagnostic accuracy was calculated.Moreover,quantitative culture and Gram＇s stain of BALF were adopted to diagnose VAP,and their diagnostic accuracy was evaluated as well.Results There were 102 patients definitely diagnosed with VAP （VAP group）,and 60 patients definitely diagnosed without VAP （no VAP group）.We found that ICOs were present in 96.08％ （98 out of 102） of VAP patients and 20.00％ （12 out of 60） of no VAP patients.The PICs were significantly higher （（9.53±6.65）％ vs.（0.52±1.33）％,P＜0.01） in VAP group.In our study,the best cutoff point for PIC to diagnose VAP was 1.5％,which had a sensitivity of 94.12％,a specificity of 88.33％,a positive predictive value （PPV） of 93.20％ and a negative predictive value （NPV） of 89.83％.The area under the receiveroperating characteristic curve was 0.956 （95％ confidence interval,0.925-0.986; P＜0.01）.When the positive quantitative culture results of BALF were used to diagnose VAP,the sensitivity,specificity,PPV and NPV were 65.69％,95.00％,95.71％ and 61.96％,respectively.Whereas they were 70.59％,76.67％,83.72％ and 60.53％,respectively,when the positive Gram＇s stain results of BALF were used to diagnose VAP.The concordance between the results of Gram＇s stain and quantitative cultures was poor,only 32.10％ （52 out of 162） was totally right,and 17.28％ （28 out of 162） was partially right.Conclusions PIC＞1.5％ has good diagnostic performance in the microscopic examination of BALF for the diagnosis of VAP.However,Gram＇s stain is not reliable for the early application of antibiotic therapy,due to the poor bacteriological predictive value.

Sequential treatment of severe pneumonia with respiratory failure and its influence on respiratory mechanical parameters and hemodynamics

BACKGROUND The pathophysiological characteristics of severe pneumonia complicated by respiratory failure comprise pulmonary parenchymal changes leading to ventilation imbalance,alveolar capillary injury,pulmonary edema,refractory hypoxemia,and reduced lung compliance.Prolonged hypoxia can cause acid-base balance disorder,peripheral circulatory failure,blood-pressure reduction,arrhythmia,and other adverse consequences.AIM To investigate sequential mechanical ventilation’s effect on severe pneumonia complicated by respiratory failure.METHODS We selected 108 patients with severe pneumonia complicated by respiratory failure who underwent mechanical ventilation between January 2018 and September 2020 at the Luhe Hospital’s Intensive Care Unit and divided them into sequential and regular groups according to a randomized trial,with each group comprising 54 patients.The sequential group received invasive and non-invasive sequential mechanical ventilation,whereas the regular group received invasive mechanical ventilation.Blood-gas parameters,hemodynamic parameters,respiratory mechanical parameters,inflammatory factors,and treatment outcomes were compared between the two groups before and after mechanical-ventilation treatment.RESULTS The arterial oxygen partial pressure and stroke volume variation values of the sequential group at 24,48,and 72 h of treatment were higher than those of the conventional group(P<0.05).The carbon dioxide partial pressure value of the sequential group at 72 h of treatment and the Raw value of the treatment group at 24 and 48 h were lower than those of the conventional group(P<0.05).The pH value of the sequential group at 24 and 72 h of treatment,the central venous pressure value of the treatment at 24 h,and the Cst value of the treatment at 24 and 48 h were higher than those of the conventional group(P<0.05).The tidal volume in the sequential group at 24 h of treatment was higher than that in the conventional group(P<0.05),the measured values of interleukin-6 and tumor necrosis factor-αin the sequential group at 72 h of treatment were lower than those in the conventional group(P<0.05),and the total time of mechanical ventilation in the sequential group was shorter than that in the conventional group,with a statistically significant difference(P<0.05).CONCLUSION Treating severe pneumonia complicated by respiratory failure with sequential mechanical ventilation is more effective in improving respiratory system compliance,reducing inflammatory response,maintaining hemodynamic stability,and improving patient blood-gas levels;however,from this study’s perspective,it cannot reduce patient mortality.

Corticosteroids for severe influenza pneumonia: A critical appraisal

Influenza pneumonia is associated with high number of severe cases requiring hospital and intensive care unit(ICU) admissions with high mortality. Systemic steroids are proposed as a valid therapeutic option even though its effects are still controversial. Heterogeneity of published data regarding study design, population demographics, severity of illness, dosing, type and timing of corticosteroids administered constitute an important limitation for drawing robust conclusions. However, it is reasonable to admit that, as it was not found any advantage of corticosteroid therapy in so diverse conditions, such beneficial effects do not exist at all. Its administration is likely to increase overall mortality and such trend is consistent regardless of the quality as well as the sample size of studies. Moreover it was shown that corticosteroids might be associated with higher incidence of hospital-acquired pneumonia and longer duration of mechanical ventilation and ICU stay. Finally, it is reasonable to conclude that corticosteroids failed to demonstrate any beneficial effects in the treatment of patients with severe influenza infection. Thus its current use in s evere influenza pneumonia should be restricted to very selected cases and in the setting of clinical trials.