Timing of Transport of Patients with COVID-19.

RATIONALE: The objective of this study was to evaluate the risk of mortality or ECMO cannulation for patients with confirmed or suspected COVID-19 transferred from sending hospitals to receiving tertiary care centers as a function of the duration of time at the sending hospital. OBJECTIVE: To determine outcomes of critically ill patients with COVID-19 who were transferred to tertiary or quarternary care medical centers. MATERIALS AND METHODS: Retrospective cohort study of critical care transports of patients to one of seven consortium tertiary care centers from March 1, 2020, through September 4, 2020. Age 14 years and older with confirmed or suspected COVID-19 transported from a sending hospital to a receiving tertiary care center by the critical care transport organization. RESULTS: Patients transported with confirmed or suspected COVID-19 to tertiary care centers had a mortality rate of 38.0%. Neither the number of days admitted, nor the number of days intubated at the sending hospital correlated with mortality (correlation coefficient 0.051 and -0.007, respectively). Similarly, neither the number of days admitted, nor number of days intubated at the sending hospital correlated with ECMO cannulation (correlation coefficient 0.008 and -0.036, respectively). CONCLUSION: It may be reasonable to transfer a critically ill COVID-19 patient to a tertiary care center even if they have been admitted at the sending hospital for several days.

Bag-Mask Ventilation Versus Apneic Oxygenation During Tracheal Intubation in Critically Ill Adults: A Secondary Analysis of 2 Randomized Trials.

Background: Hypoxemia is common during tracheal intubation in intensive care units. To prevent hypoxemia during intubation, 2 methods of delivering oxygen between induction and laryngoscopy have been proposed: bag-mask ventilation and supplemental oxygen delivered by nasal cannula without ventilation (apneic oxygenation). Whether one of these approaches is more effective for preventing hypoxemia during intubation of critically ill patients is unknown. Methods: We performed a secondary analysis of data from 138 patients enrolled in 2, consecutive randomized trials of airway management in an academic intensive care unit. A total of 61 patients were randomized to receive bag-mask ventilation in a trial comparing bag-mask ventilation to none, and 77 patients were randomized to receive 100% oxygen at 15 L/min by nasal cannula in a trial comparing apneic oxygenation to none. Using multivariable linear regression accounting for age, body mass index, severity of illness, and oxygen saturation at induction, we compared patients assigned to bag-mask ventilation with those assigned to apneic oxygenation regarding lowest oxygen saturations from induction to 2 min after intubation. Results: Patients assigned to bag-mask ventilation and apneic oxygenation were similar at baseline. The median lowest oxygen saturation was 96% (interquartile range [IQR] 89%-100%) in the bag-mask ventilation group and 92% (IQR 84%-99%) in the apneic oxygenation group. After adjustment for prespecified confounders, bag-mask ventilation was associated with a higher lowest oxygen saturation compared to apneic oxygenation (mean difference, 4.2%; 95% confidence interval, 0.7%-7.8%; P = .02). The incidence of severe hypoxemia (oxygen saturation<80%) was 6.6% in the bag-mask ventilation group and 15.6% in the apneic oxygenation group (adjusted odds ratio, 0.33; P = .09). Conclusions: This secondary analysis of patients assigned to bag-mask ventilation and apneic oxygenation during 2 clinical trials suggests that bag-mask ventilation is associated with higher oxygen saturation during intubation compared to apneic oxygenation.

Effect of Fluid Bolus Administration on Cardiovascular Collapse Among Critically Ill Patients Undergoing Tracheal Intubation: A Randomized Clinical Trial.

Importance: Hypotension is common during tracheal intubation of critically ill adults and increases the risk of cardiac arrest and death. Whether administering an intravenous fluid bolus to critically ill adults undergoing tracheal intubation prevents severe hypotension, cardiac arrest, or death remains uncertain. Objective: To determine the effect of fluid bolus administration on the incidence of severe hypotension, cardiac arrest, and death. Design, Setting, and Participants: This randomized clinical trial enrolled 1067 critically ill adults undergoing tracheal intubation with sedation and positive pressure ventilation at 11 intensive care units in the US between February 1, 2019, and May 24, 2021. The date of final follow-up was June 21, 2021. Interventions: Patients were randomly assigned to receive either a 500-mL intravenous fluid bolus (n = 538) or no fluid bolus (n = 527). Main Outcomes and Measures: The primary outcome was cardiovascular collapse (defined as new or increased receipt of vasopressors or a systolic blood pressure <65 mm Hg between induction of anesthesia and 2 minutes after tracheal intubation, or cardiac arrest or death between induction of anesthesia and 1 hour after tracheal intubation). The secondary outcome was the incidence of death prior to day 28, which was censored at hospital discharge. Results: Among 1067 patients randomized, 1065 (99.8%) completed the trial and were included in the primary analysis (median age, 62 years [IQR, 51-70 years]; 42.1% were women). Cardiovascular collapse occurred in 113 patients (21.0%) in the fluid bolus group and in 96 patients (18.2%) in the no fluid bolus group (absolute difference, 2.8% [95% CI, -2.2% to 7.7%]; P = .25). New or increased receipt of vasopressors occurred in 20.6% of patients in the fluid bolus group compared with 17.6% of patients in the no fluid bolus group, a systolic blood pressure of less than 65 mm Hg occurred in 3.9% vs 4.2%, respectively, cardiac arrest occurred in 1.7% vs 1.5%, and death occurred in 0.7% vs 0.6%. Death prior to day 28 (censored at hospital discharge) occurred in 218 patients (40.5%) in the fluid bolus group compared with 223 patients (42.3%) in the no fluid bolus group (absolute difference, -1.8% [95% CI, -7.9% to 4.3%]; P = .55). Conclusions and Relevance: Among critically ill adults undergoing tracheal intubation, administration of an intravenous fluid bolus compared with no fluid bolus did not significantly decrease the incidence of cardiovascular collapse. Trial Registration: ClinicalTrials.gov Identifier: NCT03787732.

Critical Care Transport of Patients With COVID-19.

PURPOSE: Critical care transport is associated with a high rate of adverse events, and the risks and outcomes of transporting critically ill patients during the COVID-19 pandemic have not been previously described. MATERIALS AND METHODS: We performed a retrospective review of transports of subjects with suspected or confirmed COVID-19 from sending hospitals to tertiary care hospitals in Boston. Follow-up data were obtained for patients transported between March 1st and April 20th, 2020. RESULTS: Of 254 charts identified, 250 patients were transported. Nine patients (3.5%) had cardiac arrest prior to transport. Twenty-nine (11.6%) had hypotension, 22 (8.8%) had a critical desaturation, and 4 (1.6%) had both en route. Hospital follow-up data were available for 189 patients. Of those intubated during their hospitalization, 44 (25.0%) had died, 59 (33.5%) had been extubated, and 13 (17.6%) had been discharged alive. For the subgroup with prior cardiac arrest, follow-up data available for 6. Of these 6, 2 died and 4 (66.7%) have been discharged alive. CONCLUSIONS: Few patients with COVID-19 had an adverse event in transport. The in-hospital mortality rate was 25%, with a 33.5% extubation rate. Patients resuscitated from cardiac arrest prior to transport had a 66.7% discharge rate among those transported to consortium hospitals.

The ED-SED Study: A Multicenter, Prospective Cohort Study of Practice Patterns and Clinical Outcomes Associated With Emergency Department SEDation for Mechanically Ventilated Patients.

OBJECTIVES: To characterize emergency department sedation practices in mechanically ventilated patients, and test the hypothesis that deep sedation in the emergency department is associated with worse outcomes. DESIGN: Multicenter, prospective cohort study. SETTING: The emergency department and ICUs of 15 medical centers. PATIENTS: Mechanically ventilated adult emergency department patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: All data involving sedation (medications, monitoring) were recorded. Deep sedation was defined as Richmond Agitation-Sedation Scale of -3 to -5 or Sedation-Agitation Scale of 2 or 1. A total of 324 patients were studied. Emergency department deep sedation was observed in 171 patients (52.8%), and was associated with a higher frequency of deep sedation in the ICU on day 1 (53.8% vs 20.3%; p < 0.001) and day 2 (33.3% vs 16.9%; p = 0.001), when compared to light sedation. Mean (SD) ventilator-free days were 18.1 (10.8) in the emergency department deep sedation group compared to 20.0 (9.8) in the light sedation group (mean difference, 1.9; 95% CI, -0.40 to 4.13). Similar results according to emergency department sedation depth existed for ICU-free days (mean difference, 1.6; 95% CI, -0.54 to 3.83) and hospital-free days (mean difference, 2.3; 95% CI, 0.26-4.32). Mortality was 21.1% in the deep sedation group and 17.0% in the light sedation group (between-group difference, 4.1%; odds ratio, 1.30; 0.74-2.28). The occurrence rate of acute brain dysfunction (delirium and coma) was 68.4% in the deep sedation group and 55.6% in the light sedation group (between-group difference, 12.8%; odds ratio, 1.73; 1.10-2.73). CONCLUSIONS: Early deep sedation in the emergency department is common, carries over into the ICU, and may be associated with worse outcomes. Sedation practice in the emergency department and its association with clinical outcomes is in need of further investigation.

A Symptom-Triggered Benzodiazepine Protocol Utilizing SAS and CIWA-Ar Scoring for the Treatment of Alcohol Withdrawal Syndrome in the Critically Ill.

BACKGROUND: There are limited data on the efficacy of symptom-triggered therapy for alcohol withdrawal syndrome (AWS) in the intensive care unit (ICU). OBJECTIVE: To evaluate the safety and efficacy of a symptom-triggered benzodiazepine protocol utilizing Riker Sedation Agitation Scale (SAS) scoring for the treatment of AWS in the ICU. METHODS: We performed a before-and-after study in a medical ICU. A protocol incorporating SAS scoring and symptom-triggered benzodiazepine dosing was implemented in place of a protocol that utilized the Clinical Institute Withdrawal Assessment for Alcohol (CIWA-Ar) scale and fixed benzodiazepine dosing. RESULTS: We enrolled 167 patients (135 in the preintervention and 32 in the postintervention group). The median duration of AWS was shorter in the postintervention (5, interquartile range [IQR] = 4-8 days) than in the preintervention group (8, IQR = 5-12 days; P < 0.01). Need for mechanical ventilation (31% vs 57%, P = 0.01), median ICU length of stay (LOS; 4, IQR = 2-7, vs 7, IQR = 4-11 days, P = 0.02), and hospital LOS (9, IQR = 6-13, vs 13, IQR = 9-18 days; P = 0.01) were less in the postintervention group. There was a reduction in mean total benzodiazepine exposure (74 ± 159 vs 450 ± 701 mg lorazepam; P < 0.01) in the postintervention group. CONCLUSION: A symptom-triggered benzodiazepine protocol utilizing SAS in critically ill patients is associated with a reduction in the duration of AWS treatment, benzodiazepine exposure, need for mechanical ventilation, and ICU and hospital LOS compared with a CIWA-Ar-based protocol using fixed benzodiazepine dosing.

Can We Trust Observational Studies Using Propensity Scores in the Critical Care Literature? A Systematic Comparison With Randomized Clinical Trials.

OBJECTIVE: To assess the degree of agreement between propensity score studies and randomized clinical trials in critical care research. DATA SOURCES: Propensity score studies published in highly cited critical care or general medicine journals or included in a previous systematic review; corresponding randomized clinical trials included in Cochrane Systematic Reviews or published in PubMed. STUDY SELECTION: We identified propensity score studies of the effects of therapeutic interventions on short- or long-term mortality. We systematically matched propensity score studies to randomized clinical trials based on patient selection criteria, interventions, and outcomes. DATA EXTRACTION: We appraised the methods of included studies and extracted treatment effect estimates to compare the results of propensity score studies and randomized clinical trials. When multiple studies were identified for the same topic, we performed meta-analyses to obtain summary treatment effect estimates. DATA SYNTHESIS: We matched 21 propensity score studies with 58 randomized clinical trials in 18 distinct comparisons (median, one propensity score study and two randomized clinical trials per comparison), for short- and long-term mortality. We found one statistically significant difference between designs (hyperoncotic albumin vs crystalloid fluids) among these 18 comparisons. Propensity score studies did not produce systematically higher (or lower) treatment effect estimates compared with randomized clinical trials, but estimates from the two designs differed by more than 30% in one third of the comparisons examined. Observational studies in critical care met widely accepted methodological standards for propensity score analyses. CONCLUSIONS: Across diverse critical care topics, propensity score studies published in high-impact journals produced results that were generally consistent with the findings of randomized clinical trials. However, caution is needed when interpreting propensity score studies because occasionally their results contradict those of randomized clinical trials and there is no reliable way to predict disagreements.

Reintubation in critically ill patients: procedural complications and implications for care.

INTRODUCTION: In critically ill patients, re-intubation is common and may be a high-risk procedure. Anticipating a difficult airway and identifying high-risk patients can allow time for life-saving preparation. Unfortunately, prospective studies have not compared the difficulty or complication rates associated with reintubation in this population. METHODS: We performed a secondary analysis of a prospective registry of in-hospital emergency airway management, focusing on patients that underwent multiple out-of-operating room intubations during a single hospitalization. Our main outcomes of interest were technical difficulty of intubation (number of attempts, need for adjuncts to direct laryngoscopy, best Cormack-Lehane grade and training level of final intubator) and the frequency of procedural complications (aspiration, arrhythmia, airway trauma, new hypotension, new hypoxia, esophageal intubation and cardiac arrest). We compared the cohort of reintubated patients to a matched cohort of singly intubated patients and compared each repeatedly intubated patient's first and last intubation. RESULTS: Our registry included 1053 patients, of which 151 patients (14%) were repeatedly intubated (median two per patient). Complications were significantly more common during last intubation compared to first (13% versus 5%, P = 0.02). The most common complications were hypotension (41%) and hypoxia (35%). These occurred despite no difference in any measure of technical difficultly across intubations. CONCLUSION: In this cohort of reintubated patients, clinically important procedural complications were significantly more common on last intubation compared to first.

Left-sided superior vena cava and venous hyperoxia masquerading as inadvertent carotid artery catheterization.

BACKGROUND: A persistent left-sided superior vena cava (PLSVC) is a rare, often asymptomatic, venous anomaly that may be first diagnosed during central venous catheterization. During chest radiograph interpretation, a PLSVC can be confused with inadvertent arterial catheterization. CASE REPORT: We describe the presentation of a 45-year-old man with end-stage liver disease who required central venous catheterization for treatment of septic shock. An aberrantly placed catheter noted on chest radiograph and an elevated central venous oxygen saturation gave the appearance of inadvertent carotid artery catheterization. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: A persistent left-sided superior vena cava can masquerade as an inadvertent cannulation of the carotid artery during central line placement. It is important for emergency physicians to be aware of this possibility when evaluating a chest radiograph with an aberrantly placed catheter. Venous hyperoxia may further complicate attempts to differentiate between arterial and venous catheterization in patients with septic shock. After confirmatory tests, the emergency physician should consider removal of the catheter due to potential complications.

Esmolol to Treat the Hemodynamic Effects of Septic Shock: A Randomized Controlled Trial.

INTRODUCTION: Septic shock is often characterized by tachycardia and a hyperdynamic hemodynamic profile. Use of the beta antagonist esmolol has been proposed as a therapy to lower heart rate, thereby improving diastolic filling time and improving cardiac output, resulting in a reduction in vasopressor support. METHODS: We conducted a two-center, open-label, randomized, Phase II trial comparing esmolol to placebo in septic shock patients with tachycardia. The primary endpoint was improvement in hemodynamics as measured by the difference in norepinephrine equivalent dose (NED) between groups at 6 hours after initiation of study drug. Secondary outcomes included assessing differences in inflammatory biomarkers and oxygen consumption (VO2). RESULTS: A total of 1,122 patients were assessed for eligibility and met inclusion criteria; 42 underwent randomization, and 40 received study interventions (18 in the esmolol arm and 22 in the usual care arm). The mean NED at 6 h was 0.30 ±â€Š0.17 mcg/kg/min in the esmolol arm compared to 0.21 ±â€Š0.19 in the standard care arm (P = 0.15). There was no difference in number of shock free days between the esmolol (2, IQR 0, 5) and control groups (2.5, IQR 0, 6) (P = 0.32). There were lower levels of C-reactive protein at 12 and 24 h in the esmolol arm, as well as a statistically significant difference in trend over time between groups. There were no differences in terms of IL-4, IL-6, IL-10, and TNFα. Among a subset who underwent VO2 monitoring, there was decreased oxygen consumption in the esmolol patients; the mean difference between groups at 24 h was -2.07 mL/kg/min (95% CI -3.82, -0.31) (P = 0.02), with a significant difference for the trend over time (P < 0.01). CONCLUSION: Among patients with septic shock, infusion of esmolol did not improve vasopressor requirements or time to shock reversal. Esmolol was associated with decreased levels of C-reactive protein over 24 h. TRIAL REGISTRATION: www.clinicaltrials.gov. Registered February 24, 2015, https://clinicaltrials.gov/ct2/show/NCT02369900.

Ruptured abdominal aortic aneurysm presenting as painless testicular ecchymosis: the scrotal sign of Bryant revisited.

The diagnosis of ruptured abdominal aortic aneurysm (AAA) is often missed as a result of an atypical presentation, resulting in increased mortality. Here we present an unusual case of painless scrotal ecchymosis as a presentation of ruptured AAA. We review the origin of the scrotal sign of Bryant and emphasize the importance of this uncommon finding as a diagnostic aid in atypical cases of ruptured AAA.

Characteristics and outcomes of patients receiving high flow nasal cannula therapy prior to mechanical ventilation in COVID-19 respiratory failure: A prospective observational study.

BACKGROUND: Treatment strategies for acute hypoxic respiratory failure secondary to coronavirus 2019 disease (COVID-19) had significant variation early in the pandemic. We sought to determine if patients treated with high flow nasal cannula (HFNC) prior to mechanical ventilation had differing outcomes compared to those treated only with conventional oxygen. METHODS: This was a prospective, observational study of patients with COVID-19 admitted to a tertiary care medical center with a diagnosis of acute hypoxic respiratory failure. Adult patients with a positive polymerase chain reaction test for COVID-19 who required mechanical ventilation were included. RESULTS: A total of 91 patients met the inclusion criteria for our study. The mean age was 68.4 years (standard deviation [SD] ± 12) and 58% were male. The mean initial partial pressure of arterial oxygen to fraction of inspired oxygen (PaO2/FiO2) ratio was 152 (SD ± 65) and was not significantly different between the HFNC group and the conventional oxygen strategy group (P = 0.95). The observed mortality rate was 30% in the HFNC group versus 52% in the conventional oxygen strategy group (P = 0.05). The multivariate odds ratio of mortality for patients on HFNC was 0.375 compared to a conventional oxygen strategy (95% confidence interval 0.122-1.151, P = 0.09). CONCLUSIONS: While HFNC appears to be safe as the initial treatment strategy for COVID-19 associated respiratory failure, HFNC did not result in a statistically significant difference in mortality compared to a conventional oxygen strategy. Further studies are needed to confirm these findings.

The effect of a tiered provider staffing model on patient outcomes during the coronavirus disease 2019 pandemic: A single-center observational study.

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, our hospital experienced a large influx of critically ill patients with acute respiratory failure. In order to increase intensive care unit (ICU) surge capacity, we adopted a "tiered model" for ICU provider staffing where multiple ICUs were staffed by noncritical care providers under the direction of an intensivist. We hypothesized that ICUs staffed with a tiered model would result in similar patient outcomes as ICU staffed with a traditional intensivist model. METHODS: We performed a single-center, observational study in seven ICUs at a tertiary care center. We included consecutive adults admitted to the ICU with acute respiratory distress syndrome (ARDS) due to COVID-19 infection. We collected baseline demographics, treatments, and outcomes of interest in traditionally staffed ICUs versus ICUs staffed with a tiered model. The primary outcome was inpatient mortality. All outcomes were censored at day 28. RESULTS: We included a total of 138 patients in our study: 66 patients were admitted to traditionally staffed ICUs and 52 were admitted to tiered staffing ICUs. Baseline characteristics were similar between groups. ARDS treatments were similar in traditionally staffed ICUs versus tiered staffing model ICUs, including daily mean tidal volume (6.2 mL/kg vs. 6.2 mL/kg, P = 0.95), median daily fluid balance (159 mL vs. 92 mL, P = 0.54), and use of prone ventilation (58% vs. 65%, P = 0.45). There was no difference in inpatient mortality between groups (50% vs. 42%, P = 0.46). We also found no difference in ventilator-free, ICU-free, vasopressor-free, and dialysis-free days between groups. CONCLUSIONS: Our results suggest that patient outcomes are similar in ICUs with traditional staffing models when compared to ICUs with a tiered staffing mode during a pandemic.

Emergency department management of the airway in obese adults.

Airway management in obese adults can be challenging, and much of the literature on this subject focuses on elective surgical cases, rather than acutely ill patients. In this article, we review the emergency department evaluation of the airway in obesity, discussing anatomy, physiology, and pharmacology. In addition, we describe techniques and devices used to improve intubating conditions in the obese patient. After our review of the relevant literature, we conclude that research in this particular area of acute care remains in its infancy.

Ultrasonography-guided peripheral intravenous catheter survival in ED patients with difficult access.

OBJECTIVES: We determined the survival and complications of ultrasonography-guided peripheral intravenous (IV) catheters in emergency department (ED) patients with difficult peripheral access. METHODS: This was a prospective, observational study conducted in an academic hospital from April to July of 2007. We included consecutive adult ED patients with difficult access who had ultrasonography-guided peripheral IVs placed. Operators completed data sheets and researchers examined admitted patients daily to assess outcomes. The primary outcome was IV survival >96 hours. As a secondary outcome, we recorded IV complications, including central line placement. We used descriptive statistics, univariate survival analysis with Kaplan Meier, and log-rank tests for data analysis. RESULTS: Seventy-five patients were enrolled. The average age was 52 years. Fifty-three percent were male, 21% obese, and 13% had a history of injection drug use. The overall IV survival rate was 56% (95% confidence interval, 44%-67%) with a median survival of 26 hours (interquartile range [IQR], 8-61). Forty-seven percent of IVs failed within 24 hours, most commonly due to infiltration. Although 47 (63%) operators reported that a central line would have been required if peripheral access was unobtainable, only 5 (7%; 95% confidence interval, 2%-15%) patients underwent central venous catheterization. Only 1 central line was placed as a result of ultrasonography-guided IV failure. We observed no infectious or thrombotic complications. CONCLUSION: Despite a high premature failure rate, ultrasonography-guided peripheral IVs appear to be an effective alternative to central line placement in ED patients with difficult access.

Feasibility and Safety of Prone Position Transport for Severe Hypoxemic Respiratory Failure Due to Coronavirus Disease 2019.

OBJECTIVES: To assess the safety and feasibility of a new protocol for interhospital critical care transport of mechanically ventilated patients in the prone position during the coronavirus disease 2019 pandemic by nurse and paramedic critical care transport teams. DESIGN: Retrospective observational study. SETTING: Single critical care transport agency serving multiple centers in the greater Boston area. PATIENTS: All transports of intubated patients in the prone position with severe hypoxemic respiratory failure secondary to coronavirus disease 2019. INTERVENTIONS: Records were reviewed for patients transported in the prone position. Major adverse events in transport, defined as severe hypoxemia (oxygen saturation < 80% or an absolute decrease in oxygen saturation > 10%), hypotension (mean arterial pressure < 65 mm Hg) not responsive to vasopressors or inotropes, endotracheal tube or vascular catheter dislodgement, and cardiac arrest, were recorded. MEASUREMENTS AND MAIN RESULTS: A total of 25 patients were transported in prone position. The mean Pao2:Fio2 ratio in the group was 101.3 mm Hg, and 76% (n = 19) were on vasopressors. Fourteen patients (56%) had hypotension with at least one episode of mean arterial pressure less than 65 mm Hg en route, and seven (28%) had an episode of oxygen desaturation less than 88%. Only one major adverse event of severe hypoxemia (oxygen saturation < 80%) was noted. CONCLUSIONS: Critical care transport of severe hypoxemic respiratory failure patients with coronavirus disease 2019 in the prone position is safe when performed by a dedicated team of critical care nurse and paramedics with an established protocol.

Protocol and statistical analysis plan for the PREventing cardiovascular collaPse with Administration of fluid REsuscitation during Induction and Intubation (PREPARE II) randomised clinical trial.

INTRODUCTION: Cardiovascular collapse is a common complication during tracheal intubation of critically ill adults. Whether administration of an intravenous fluid bolus prevents cardiovascular collapse during tracheal intubation remains uncertain. A prior randomised trial found fluid bolus administration to be ineffective overall but suggested potential benefit for patients receiving positive pressure ventilation during tracheal intubation. METHODS AND ANALYSIS: The PREventing cardiovascular collaPse with Administration of fluid REsuscitation during Induction and Intubation (PREPARE II) trial is a prospective, multi-centre, non-blinded randomised trial being conducted in 13 academic intensive care units in the USA. The trial will randomise 1065 critically ill adults undergoing tracheal intubation with planned use of positive pressure ventilation (non-invasive ventilation or bag-mask ventilation) between induction and laryngoscopy to receive 500 mL of intravenous crystalloid or no intravenous fluid bolus. The primary outcome is cardiovascular collapse, defined as any of: systolic blood pressure <65 mm Hg, new or increased vasopressor administration between induction and 2 min after intubation, or cardiac arrest or death between induction and 1 hour after intubation. The primary analysis will be an unadjusted, intention-to-treat comparison of the primary outcome between patients randomised to fluid bolus administration and patients randomised to no fluid bolus administration using a χ2 test. The sole secondary outcome is 28-day in-hospital mortality. Enrolment began on 1 February 2019 and is expected to conclude in June 2020. ETHICS AND DISSEMINATION: The trial was approved by either the central institutional review board at Vanderbilt University Medical Center or the local institutional review board at each trial site. Results will be submitted for publication in a peer-reviewed journal and presented at scientific conferences. TRIAL REGISTRATION NUMBER: NCT03787732.