Nicholas M. Mohr

Lower tidal volume at initiation of mechanical ventilation may reduce progression to acute respiratory distress syndrome: a systematic review

IntroductionThe most appropriate tidal volume in patients without acute respiratory distress syndrome (ARDS) is controversial and has not been rigorously examined. Our objective was to determine whether a mechanical ventilation strategy using lower tidal volume is associated with a decreased incidence of progression to ARDS when compared with a higher tidal volume strategy.MethodsA systematic search of MEDLINE, EMBASE, CINAHL, the Cochrane Library, conference proceedings, and clinical trial registration was performed with a comprehensive strategy. Studies providing information on mechanically ventilated patients without ARDS at the time of initiation of mechanical ventilation, and in which tidal volume was independently studied as a predictor variable for outcome, were included. The primary outcome was progression to ARDS.ResultsThe search yielded 1,704 studies, of which 13 were included in the final analysis. One randomized controlled trial was found; the remaining 12 studies were observational. The patient cohorts were significantly heterogeneous in composition and baseline risk for developing ARDS; therefore, a meta-analysis of the data was not performed. The majority of the studies (n = 8) showed a decrease in progression to ARDS with a lower tidal volume strategy. ARDS developed early in the course of illness (5 hours to 3.7 days). The development of ARDS was associated with increased mortality, lengths of stay, mechanical ventilation duration, and nonpulmonary organ failure.ConclusionsIn mechanically ventilated patients without ARDS at the time of endotracheal intubation, the majority of data favors lower tidal volume to reduce progression to ARDS. However, due to significant heterogeneity in the data, no definitive recommendations can be made. Further randomized controlled trials examining the role of lower tidal volumes in patients without ARDS, controlling for ARDS risk, are needed.2013 Fuller et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Generational influences in academic emergency medicine: Teaching and learning, mentoring, and technology (Part I)

For the first time in history, four generations are working together-traditionalists, baby boomers, generation Xers (Gen Xers), and millennials. Members of each generation carry with them a unique perspective of the world and interact differently with those around them. Through a review of the literature and consensus by modified Delphi methodology of the Society for Academic Emergency Medicine Aging and Generational Issues Task Force, the authors have developed this two-part series to address generational issues present in academic emergency medicine (EM). Understanding generational characteristics and mitigating strategies can help address some common issues encountered in academic EM. Through recognition of the unique characteristics of each of the generations with respect to teaching and learning, mentoring, and technology, academicians have the opportunity to strategically optimize interactions with one another.

Mechanical Ventilation and Acute Lung Injury in Emergency Department Patients With Severe Sepsis and Septic Shock: An Observational Study

OBJECTIVES The objectives were to characterize the use of mechanical ventilation in the emergency department (ED), with respect to ventilator settings, monitoring, and titration and to determine the incidence of progression to acute lung injury (ALI) after admission, examining the influence of factors present in the ED on ALI progression. METHODS This was a retrospective, observational cohort study of mechanically ventilated patients with severe sepsis and septic shock (June 2005 to May 2010), presenting to an academic ED with an annual census of >95,000 patients. All patients in the study (n = 251) were analyzed for characterization of mechanical ventilation use in the ED. The primary outcome variable of interest was the incidence of ALI progression after intensive care unit (ICU) admission from the ED and risk factors present in the ED associated with this outcome. Secondary analyses included ALI present in the ED and clinical outcomes comparing all patients progressing to ALI versus no ALI. To assess predictors of progression to ALI, significant variables in univariable analyses at a p ≤ 0.10 level were candidates for inclusion in a bidirectional, stepwise, multivariable logistic regression analysis. RESULTS Lung-protective ventilation was used in 68 patients (27.1%) and did not differ based on ALI status. Delivered tidal volume was highly variable, with a median tidal volume delivered of 8.8 mL/kg ideal body weight (IBW; interquartile range [IQR] = 7.8 to 10.0) and a range of 5.2 to 14.6 mL/kg IBW. Sixty-nine patients (27.5%) in the entire cohort progressed to ALI after admission to the hospital, with a mean (±SD) onset of 2.1 (±1) days. Multivariable logistic regression analysis demonstrated that a higher body mass index (BMI), higher Sequential Organ Failure Assessment (SOFA) score, and ED vasopressor use were associated with progression to ALI. There was no association between ED ventilator settings and progression to ALI. Compared to patients who did not progress to ALI, patients progressing to ALI after admission from the ED had an increase in mechanical ventilator duration, vasopressor dependence, and hospital length of stay (LOS). CONCLUSIONS Lung-protective ventilation is uncommon in the ED, regardless of ALI status. Given the frequency of ALI in the ED, the progression shortly after ICU admission, and the clinical consequences of this syndrome, the effect of ED-based interventions aimed at reducing the sequelae of ALI should be investigated further.

The use of inhaled prostaglandins in patients with ARDS: a systematic review and meta-analysis.

OBJECTIVE This study aimed to determine whether inhaled prostaglandins are associated with improvement in pulmonary physiology or mortality in patients with ARDS and assess adverse effects. METHODS The following data sources were used: PubMed, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, reference lists, conference proceedings, and ClinicalTrials.gov. Studies selected included randomized controlled trials and nonrandomized studies. For data extraction, two reviewers independently screened titles and abstracts for eligibility. With regard to data synthesis, 25 studies (two RCTs) published over 21 years (1993-2014) were included. The PROSPERO registration number was CRD42014013180. RESULTS One randomized controlled trial showed no difference in the change in mean Pao2 to Fio2 ratio when comparing inhaled alprostadil to placebo: 141.2 (95% CI, 120.8-161.5) to 161.5 (95% CI, 134.6-188.3) vs 163.4 (95% CI, 140.8-186.0) to 186.8 (95% CI, 162.9-210.7), P = .21. Meta-analysis of the remaining studies demonstrated that inhaled prostaglandins were associated with improvement in Pao2 to Fio2 ratio (16 studies; 39.0% higher; 95% CI, 26.7%-51.3%), and Pao2 (eight studies; 21.4% higher; 95% CI, 12.2%-30.6%), and a decrease in pulmonary artery pressure (-4.8 mm Hg; 95% CI, -6.8 mm Hg to -2.8 mm Hg). Risk of bias and heterogeneity were high. Meta-regression found no association with publication year (P = .862), baseline oxygenation (P = .106), and ARDS etiology (P = .816) with the treatment effect. Hypotension occurred in 17.4% of patients in observational studies. CONCLUSIONS In ARDS, inhaled prostaglandins improve oxygenation and decrease pulmonary artery pressures and may be associated with harm. Data are limited both in terms of methodologic quality and demonstration of clinical benefit. The use of inhaled prostaglandins in ARDS needs further study.OBJECTIVE: Th is study aimed to determine whether inhaled prostaglandins are associated with improvement in pulmonary physiology or mortality in patients with ARDS and assess adverse eff ects . METHODS: Th e following data sources were used: PubMed, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, reference lists, conference proceedings, and ClinicalTrials.gov. Studies selected included randomized controlled trials and nonrandomized studies. For data extraction, two reviewers independently screened titles and abstracts for eligibility. With regard to data synthesis, 25 studies (two RCTs) published over 21 years (1993-2014) were included. The PROSPERO registration number was CRD42014013180. RESULTS: One randomized controlled trial showed no difference in the change in mean Pa o 2 to F io 2 ratio when comparing inhaled alprostadil to placebo: 141.2 (95% CI, 120.8-161.5) to 161.5 (95% CI, 134.6-188.3) vs 163.4 (95% CI, 140.8-186.0) to 186.8 (95% CI, 162.9-210.7), P 5 .21. Meta-analysis of the remaining studies demonstrated that inhaled prostaglandins were associated with improvement in Pa o 2 to F io 2 ratio (16 studies; 39.0% higher; 95% CI, 26.7%-51.3%), and Pa o 2 (eight studies; 21.4% higher; 95% CI, 12.2%-30.6%), and a decrease in pulmonary artery pressure ( 2 4.8 mm Hg; 95% CI, 2 6.8 mm Hg to 2 2.8 mm Hg). Risk of bias and heterogeneity were high. Meta-regression found no association with publication year ( P 5 .862), baseline oxygenation ( P 5 .106), and ARDS etiology ( P 5 .816) with the treatment effect. Hypotension occurred in 17.4% of patients in observational studies. CONCLUSIONS: In ARDS, inhaled prostaglandins improve oxygenation and decrease pulmonary artery pressures and may be associated with harm. Data are limited both in terms of methodologic quality and demonstration of clinical benefi t. Th e use of inhaled prostaglandins in ARDS needs further study. CHEST 2015; 147 ( 6 ): 1510 1522 [ Original Research Critical Care ]

Mechanical Ventilation and ARDS in the ED: A Multicenter, Observational, Prospective, Cross-sectional Study

BACKGROUND There are few data regarding mechanical ventilation and ARDS in the ED. This could be a vital arena for prevention and treatment. METHODS This study was a multicenter, observational, prospective, cohort study aimed at analyzing ventilation practices in the ED. The primary outcome was the incidence of ARDS after admission. Multivariable logistic regression was used to determine the predictors of ARDS. RESULTS We analyzed 219 patients receiving mechanical ventilation to assess ED ventilation practices. Median tidal volume was 7.6 mL/kg predicted body weight (PBW) (interquartile range, 6.9-8.9), with a range of 4.3 to 12.2 mL/kg PBW. Lung-protective ventilation was used in 122 patients (55.7%). The incidence of ARDS after admission from the ED was 14.7%, with a mean onset of 2.3 days. Progression to ARDS was associated with higher illness severity and intubation in the prehospital environment or transferring facility. Of the 15 patients with ARDS in the ED (6.8%), lung-protective ventilation was used in seven (46.7%). Patients who progressed to ARDS experienced greater duration in organ failure and ICU length of stay and higher mortality. CONCLUSIONS Lung-protective ventilation is infrequent in patients receiving mechanical ventilation in the ED, regardless of ARDS status. Progression to ARDS is common after admission, occurs early, and worsens outcome. Patient- and treatment-related factors present in the ED are associated with ARDS. Given the limited treatment options for ARDS, and the early onset after admission from the ED, measures to prevent onset and to mitigate severity should be instituted in the ED. TRIAL REGISTRY ClinicalTrials.gov; No.: NCT01628523; URL: www.clinicaltrials.gov.

Interhospital Transfer Delays Appropriate Treatment for Patients With Severe Sepsis and Septic Shock: A Retrospective Cohort Study.

Objective:To test the hypothesis that interhospital transfer causes significant delays in the administration of appropriate antibiotics and compliance with the completion of Surviving Sepsis Bundle elements. Design:Single-center retrospective cohort study. Setting:A comprehensive 60,000-visit emergency department at a 711-bed Midwestern academic medical center. Patients:Patients with severe sepsis and septic shock treated between 2009 and 2014 were identified by International Classification of Diseases,9th Revision, Clinical Modification, codes, then divided into two cohorts: 1) transfer patients who arrived at the tertiary academic center after receiving care in a local community hospital and 2) control patients who presented directly to the tertiary academic center emergency department. Interventions:None. Measurement and Main Results:One hundred ninety-three patients were included. Transfer patients were more likely to require surgery in the hospital (p < 0.001) and require ICU care (p = 0.001) but had similar illness severity based on (Acute Physiology and Chronic Health Evaluation II, 17.7 vs 17.5; p = 0.662). Antibiotic administration at 1 and 3 hours was comparable between the two cohorts, but initial antibiotic appropriateness was lower in transfer patients (34% vs 79%; p < 0.001). Transfer patients were less likely to have fluid resuscitation started by 3 hours (54% vs 89%; p < 0.001), but they were not less likely to receive an adequate fluid bolus (30 mL/kg) by the time of hospital admission (p = 0.056). There were no differences in ICU length of stay or mortality. Conclusions:Interhospital transfer significantly delays administration of appropriate initial antibiotics and resuscitation therapy. Future studies are needed to identify strategies of providing regional sepsis care prior to transfer to tertiary centers and to continue care pathways during the interhospital transfer process.

Reducing the burden of acute respiratory distress syndrome: the case for early intervention and the potential role of the emergency department

ABSTRACT The mortality for acute respiratory distress syndrome (ARDS) remains unacceptably high. Success in clinical trials has been limited, resulting in a lack of effective therapies to treat the syndrome. The projected increase in mechanically ventilated patients and global need for critical care services suggests that the clinical and research landscape in ARDS can no longer be confined to the intensive care unit. A demonstrable minority of patients present to the emergency department (ED) with ARDS, and ARDS onset typically occurs shortly after intensive care unit admission. Furthermore, the ED is an entry point for many of the highest-risk patients for ARDS development and progression. These facts, combined with prolonged lengths of stay in the ED, suggest that the ED could represent a window of opportunity for treatment and preventive strategies, as well as clinical trial enrollment. This review aims to discuss some of the potential strategies that may prevent or alter the trajectory of ARDS, with a focus on the potential role the ED could play in reducing the burden of this syndrome.

Lung-Protective Ventilation Initiated in the Emergency Department (LOV-ED): A Quasi-Experimental, Before-After Trial

Study objective: We evaluated the efficacy of an emergency department (ED)–based lung‐protective mechanical ventilation protocol for the prevention of pulmonary complications. Methods: This was a quasi‐experimental, before‐after study that consisted of a preintervention period, a run‐in period of approximately 6 months, and a prospective intervention period. The intervention was a multifaceted ED‐based mechanical ventilator protocol targeting lung‐protective tidal volume, appropriate setting of positive end‐expiratory pressure, rapid oxygen weaning, and head‐of‐bed elevation. A propensity score–matched analysis was used to evaluate the primary outcome, which was the composite incidence of acute respiratory distress syndrome and ventilator‐associated conditions. Results: A total of 1,192 patients in the preintervention group and 513 patients in the intervention group were included. Lung‐protective ventilation increased by 48.4% in the intervention group. In the propensity score–matched analysis (n=490 in each group), the primary outcome occurred in 71 patients (14.5%) in the preintervention group compared with 36 patients (7.4%) in the intervention group (adjusted odds ratio 0.47; 95% confidence interval [CI] 0.31 to 0.71). There was an increase in ventilator‐free days (mean difference 3.7; 95% CI 2.3 to 5.1), ICU‐free days (mean difference 2.4; 95% CI 1.0 to 3.7), and hospital‐free days (mean difference 2.4; 95% CI 1.2 to 3.6) associated with the intervention. The mortality rate was 34.1% in the preintervention group and 19.6% in the intervention group (adjusted odds ratio 0.47; 95% CI 0.35 to 0.63). Conclusion: Implementing a mechanical ventilator protocol in the ED is feasible and is associated with significant improvements in the delivery of safe mechanical ventilation and clinical outcome.

Original Research: Critical CareThe Use of Inhaled Prostaglandins in Patients With ARDS

OBJECTIVE This study aimed to determine whether inhaled prostaglandins are associated with improvement in pulmonary physiology or mortality in patients with ARDS and assess adverse effects. METHODS The following data sources were used: PubMed, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, reference lists, conference proceedings, and ClinicalTrials.gov. Studies selected included randomized controlled trials and nonrandomized studies. For data extraction, two reviewers independently screened titles and abstracts for eligibility. With regard to data synthesis, 25 studies (two RCTs) published over 21 years (1993-2014) were included. The PROSPERO registration number was CRD42014013180. RESULTS One randomized controlled trial showed no difference in the change in mean Pao2 to Fio2 ratio when comparing inhaled alprostadil to placebo: 141.2 (95% CI, 120.8-161.5) to 161.5 (95% CI, 134.6-188.3) vs 163.4 (95% CI, 140.8-186.0) to 186.8 (95% CI, 162.9-210.7), P = .21. Meta-analysis of the remaining studies demonstrated that inhaled prostaglandins were associated with improvement in Pao2 to Fio2 ratio (16 studies; 39.0% higher; 95% CI, 26.7%-51.3%), and Pao2 (eight studies; 21.4% higher; 95% CI, 12.2%-30.6%), and a decrease in pulmonary artery pressure (-4.8 mm Hg; 95% CI, -6.8 mm Hg to -2.8 mm Hg). Risk of bias and heterogeneity were high. Meta-regression found no association with publication year (P = .862), baseline oxygenation (P = .106), and ARDS etiology (P = .816) with the treatment effect. Hypotension occurred in 17.4% of patients in observational studies. CONCLUSIONS In ARDS, inhaled prostaglandins improve oxygenation and decrease pulmonary artery pressures and may be associated with harm. Data are limited both in terms of methodologic quality and demonstration of clinical benefit. The use of inhaled prostaglandins in ARDS needs further study.OBJECTIVE: Th is study aimed to determine whether inhaled prostaglandins are associated with improvement in pulmonary physiology or mortality in patients with ARDS and assess adverse eff ects . METHODS: Th e following data sources were used: PubMed, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, reference lists, conference proceedings, and ClinicalTrials.gov. Studies selected included randomized controlled trials and nonrandomized studies. For data extraction, two reviewers independently screened titles and abstracts for eligibility. With regard to data synthesis, 25 studies (two RCTs) published over 21 years (1993-2014) were included. The PROSPERO registration number was CRD42014013180. RESULTS: One randomized controlled trial showed no difference in the change in mean Pa o 2 to F io 2 ratio when comparing inhaled alprostadil to placebo: 141.2 (95% CI, 120.8-161.5) to 161.5 (95% CI, 134.6-188.3) vs 163.4 (95% CI, 140.8-186.0) to 186.8 (95% CI, 162.9-210.7), P 5 .21. Meta-analysis of the remaining studies demonstrated that inhaled prostaglandins were associated with improvement in Pa o 2 to F io 2 ratio (16 studies; 39.0% higher; 95% CI, 26.7%-51.3%), and Pa o 2 (eight studies; 21.4% higher; 95% CI, 12.2%-30.6%), and a decrease in pulmonary artery pressure ( 2 4.8 mm Hg; 95% CI, 2 6.8 mm Hg to 2 2.8 mm Hg). Risk of bias and heterogeneity were high. Meta-regression found no association with publication year ( P 5 .862), baseline oxygenation ( P 5 .106), and ARDS etiology ( P 5 .816) with the treatment effect. Hypotension occurred in 17.4% of patients in observational studies. CONCLUSIONS: In ARDS, inhaled prostaglandins improve oxygenation and decrease pulmonary artery pressures and may be associated with harm. Data are limited both in terms of methodologic quality and demonstration of clinical benefi t. Th e use of inhaled prostaglandins in ARDS needs further study. CHEST 2015; 147 ( 6 ): 1510 1522 [ Original Research Critical Care ]

EMERGENCY DEPARTMENT VANCOMYCIN USE: DOSING PRACTICES AND ASSOCIATED OUTCOMES

BACKGROUND Emergency Department (ED) dosing of vancomycin and its effect on outcomes has not been examined. STUDY OBJECTIVE To describe current vancomycin dosing practices for ED patients, focusing on patient factors associated with administration, dosing accuracy based on patient body weight, and clinical outcomes. METHODS Single-center, retrospective cohort study of vancomycin administered in the ED over 18 months in an academic, tertiary care ED. Data were collected on 4656 patients. Data were analyzed using a generalized estimating equations model to account for multiple doses being administered to the same patient. RESULTS The ED dose was continued, unchanged, in 2560 admitted patients (83.8%). The correct dose was given 980 times (22.1%), 3143 doses (70.7%) were underdosed, and 318 were overdosed (7.2%). Increasing weight was associated with underdosing (adjusted odds ratio 1.52 per 10 kg body weight, p < 0.001). Patients who received doses of vancomycin > 20 mg/kg had longer hospital length of stay (p = 0.005); were more likely to spend ≥ 3 days in the hospital (odds ratio [OR] 1.49; 95% confidence interval [CI] 1.12-1.98, p = 0.006); and more likely to die (OR 1.88; 95% CI 1.22-2.90, p = 0.004). CONCLUSION In this largest study to date examining ED vancomycin dosing, vancomycin was commonly given. Dosing outside the recommended range was frequent, and especially prevalent in patients with a higher body weight. The ED dose of vancomycin was frequently continued as an inpatient, regardless of dosing accuracy. There is significant room for improvement in dosing accuracy and indication. Vancomycin dosing in the ED may also affect clinical outcomes.