Predictors of the complication of postintubation hypotension during emergency airway management

Association of Shock Indices with Peri-Intubation Hypotension and Other Outcomes: A Sub-Study of the KEEP PACE Trial

BACKGROUND

Based on current evidence, there appears to be an association between peri-intubation hypotension and patient morbidity and mortality. Studies have identified shock indices as possible pre-intubation risk factors for peri-intubation hypotension. Thus, we sought to evaluate the association between shock index (SI), modified shock index (MSI), and diastolic shock index (DSI) and peri-intubation hypotension along with other outcomes.

METHODS

The present study is a sub-study of a randomized controlled trial involving critically ill patients undergoing intubation. We defined peri-intubation hypotension as a decrease in mean arterial pressure <65 mm Hg and/or a reduction of 40% from baseline; or the initiation of, or increase in infusion dosage of, any vasopressor medication (bolus or infusion) during the 30-min period following intubation. SI, MSI, and DSI were analyzed as continuous variables and categorically using pre-established cut-offs. We also explored the effect of age on shock indices.

RESULTS

A total of 151 patients were included in the analysis. Mean pre-intubation SI was 1.0  ±  0.3, MSI 1.5  ±  0.5, and DSI 1.9  ±  0.7. Increasing SI, MSI, and DSI were significantly associated with peri-intubation hypotension (OR [95% CI] per 0.1 increase  =  1.16 [1.04, 1.30], P  =  .009 for SI; 1.14 [1.05, 1.24], P  =  .003 for MSI; and 1.11 [1.04, 1.19], P  =  .003 for DSI). The area under the ROC curves did not differ across shock indices (0.66 vs 0.67 vs 0.69 for SI, MSI, and DSI respectively; P  =  .586). Increasing SI, MSI, and DSI were significantly associated with worse sequential organ failure assessment (SOFA) score (spearman rank correlation: r  =  0.30, r  =  0.40, and r  =  0.45 for SI, MSI, and DSI, respectively, all P < .001) but not with other outcomes. There was no significant impact when incorporating age.

CONCLUSIONS

Increasing SI, MSI, and DSI were all significantly associated with peri-intubation hypotension and worse SOFA scores but not with other outcomes. Shock indices remain a useful bedside tool to assess the potential likelihood of peri-intubation hypotension.

TRIAL REGISTRATION

ClinicalTrials.gov identifier - NCT02105415.

Impact of resuscitation adjuncts on postintubation hypotension in patients with isolated traumatic brain injury

INTRODUCTION

Postintubation hypotension (PIH) is a risk factor of endotracheal intubation (ETI) after injury. For those with traumatic brain injury (TBI), one episode of hypotension can potentiate that injury. This study aimed to identify the resuscitation adjuncts that may decrease the incidence of PIH in this patient population.

METHODS

This is a 4-year (2019-2022) prospective observational study at a level I trauma center. Adult (18 years or older) patients with isolated TBI requiring ETI in the trauma bay were included. Blood pressures were measured 15 minutes preintubation and postintubation. Primary outcome was PIH, defined as a decrease in systolic blood pressure of ≥20% from baseline or to ≤80 mm Hg, or any decrease in mean arterial pressure to ≤60 mm Hg. Multivariable logistic regression was performed to identify the associations of preintubation vasopressor, hypertonic saline (HTS), packed red blood cell, and crystalloids on PIH incidence.

RESULTS

Of the 490 enrolled patients, 16% had mild (head AIS, ≤2), 35% had moderate (head AIS, 3-4), and 49% had severe TBI (head AIS, ≥5). The mean ± SD age was 42 ± 22 years, and 71% were male. The median ISS, head AIS, and Glasgow Coma Scale were 26 (19-38), 4 (3-5), and 6 (3-11), respectively. The mean ± SD systolic blood pressure 15 minutes preintubation and postintubation were 118 ± 46 and 106 ± 45, respectively. Before intubation, 31% received HTS; 10%, vasopressors; 20%, crystalloids; and 14%, at least 1 U of packed red blood cell (median, 2 [1-2] U). Overall, 304 patients (62%) developed PIH. On multivariable regression analysis, preintubation use of vasopressors and HTS was associated with significantly decreased odds of PIH independent of TBI severity, 0.310 (0.102-0.944, p = 0.039) and 0.393 (0.219-0.70, p = 0.002), respectively.

CONCLUSION

Nearly two thirds of isolated TBI patients developed PIH. Preintubation vasopressors and HTS are associated with a decreased incidence of PIH. Such adjuncts should be considered prior to ETI in patients with suspected TBI.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Derivation of the Difficult Airway Physiological Score (DAPS) in adults undergoing endotracheal intubation in the emergency department

BACKGROUND

Prediction of serious outcomes among patients with physiological instability is crucial in airway management. In this study, we aim to develop a score to predict serious outcomes following intubation in critically ill adults with physiological instability by using clinical and laboratory parameters collected prior to intubation.

METHOD

This single-center analytical cross-sectional study was conducted in the Emergency Department from 2016 to 2020. The airway score was derived using the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) methodology. To gauge model's performance, the train-test split technique was utilized. The discrete random number generation approach was used to divide the dataset into two groups: development (training) and validation (testing). The validation dataset's instances were used to calculate the final score, and its validity was measured using ROC analysis and area under the curve (AUC). By computing the Youden's J statistic using the metrics sensitivity, specificity, positive predictive value, and negative predictive value, the discriminating factor of the additive score was determined.

RESULTS

The mean age of the 1021 patients who needed endotracheal intubations was 52.2 years (± 17.5), and 632 (62%) of them were male. In the development dataset, there were 527 (64.9%) physiologically difficult airways, 298 (36.7%) post-intubation hypotension, 124 (12%) cardiac arrest, 347 (42.7%) shock index > 0.9, and 456 [56.2%] instances of pH < 7.3. On the contrary, in the validation dataset, there were 143 (68.4%) physiologically difficult airways, 33 (15.8%) post-intubation hypotension, 41 (19.6%) cardiac arrest, 87 (41.6%) shock index > 0.9, and 121 (57.9%) had pH < 7.3, respectively. There were 12 variables in the difficult airway physiological score (DAPS), and a DAPS of 9 had an area under the curve of 0.857. The accuracy of DAPS was 77%, the sensitivity was 74%, the specificity was 83.3%, and the positive predictive value was 91%.

CONCLUSION

DAPS demonstrated strong discriminating ability for anticipating physiologically challenging airways. The proposed model may be helpful in the clinical setting for screening patients who are at high risk of deterioration.

Factors Associated with Postintubation Hypotension Among Patients with Suspected Sepsis in Emergency Department

Purpose

Postintubation hypotension (PIH) is a recognized complication that increases both in-hospital mortality and hospital length of stay. Sepsis is reportedly a factor associated with PIH. However, no study to date has examined which factors, including the intubation method, may be clinical predictors of PIH in patients with sepsis. This study aims to investigate factors associated with the occurrence of PIH in patients with suspected sepsis in emergency department.

Patients and Methods

This retrospective cross-sectional study was performed over a 5-year period (January 2013-December 2017) and involved patients with suspected sepsis who underwent endotracheal intubation in the emergency department of Ramathibodi Hospital. The patients were divided into those with and without PIH, and factors associated with the occurrence of PIH were analyzed. PIH was defined as any recorded systolic blood pressure of <90 mmHg within 60 minutes of intubation.

Results

In total, 394 patients with suspected sepsis were included. PIH occurred in 106 patients (26.9%) and was associated with increased in-hospital mortality (43.00% in the PIH group vs 31.25% in the non-PIH group, P = 0.034). Multivariable logistic regression showed that the factors associated with PIH were an age of ≥61 years (adjusted odds ratio [aOR] 2.25; 95% confidence interval [CI] 1.14-4.43; P = 0.019) and initial serum lactate concentration of >4.4 mmol/L (aOR 2.00; 95% CI 1.16-3.46; P = 0.013). Rapid sequence intubation and difference types of induction agents was unrelated to PIH.

Conclusion

Monitoring the development of PIH in patients with sepsis is essential because of its correlation with higher in-hospital mortality. This is particularly critical for older individuals and those with severe infections and high initial lactate concentrations.

A Nomogram Model for Post-Intubation Hypotension in Patients with Severe Pneumonia in the Emergency Department

Background

Post-intubation hypotension (PIH) frequently occurs in the management of critically ill patients and is associated with prognosis. The study aimed to construct a prediction model for PIH events by analyzing risk factors in patients with severe pneumonia in the emergency department.

Methods

We retrospectively enrolled 572 patients with severe pneumonia diagnosed in the emergency department of West China Hospital of Sichuan University. Five hundred patients with severe pneumonia who underwent endotracheal intubation were included in the study. All patients were randomized according to 7:3 and divided into a training cohort (n=351) and a validation cohort (n=149). Risk factors for PIH were analyzed using Least Absolute Shrinkage and Selection Operator (LASSO) and multivariable logistic regression. Calibration curves, receiver operating characteristic (ROC) curve, and decision curve analysis were applied to assess the predictive model's fitness, discrimination, and clinical utility.

Results

A total of 500 patients with severe pneumonia who underwent endotracheal intubation were enrolled in this study, and PIH occurred in 234 (46.8%) of these patients. Age, heart rate, systolic blood pressure, chronic obstructive pulmonary disease, acute physiology and chronic health evaluation II score, and induction agent use were identified as significant risk factors for the occurrence of PIH. Additionally, the body mass index was the opposite of the above. The area under the ROC curve (AUC) for the model was 0.856 (95% CI, 0.818-0.894) in the training cohort and 0.849 (95% CI, 0.788-0.910) in the validation cohort. The nomogram model was validated and demonstrated good calibration and high net clinical benefit. Finally, to facilitate application by clinicians, an online server has been set up which can be accessed free of charge via the website https://chinahospitals.shinyapps.io/DynNomapp/.

Conclusion

The nomogram is used for individualized prediction of patients with severe pneumonia prior to intubation and is simple to perform with high clinical value.

Sedative Dose for Rapid Sequence Intubation and Postintubation Hypotension: Is There an Association?

STUDY OBJECTIVE

For patients with hemodynamic instability undergoing rapid sequence intubation, experts recommend reducing the sedative medication dose to minimize the risk of further hemodynamic deterioration. Scant data support this practice for etomidate and ketamine. We sought to determine if the dose of etomidate or ketamine was independently associated with postintubation hypotension.

METHODS

We analyzed data from the National Emergency Airway Registry from January 2016 to December 2018. Patients aged 14 years or older were included if the first intubation attempt was facilitated with etomidate or ketamine. We used multivariable modeling to determine whether drug dose in milligrams per kilogram of patient weight was independently associated with postintubation hypotension (systolic blood pressure < 100 mm Hg).

RESULTS

We analyzed 12,175 intubation encounters facilitated by etomidate and 1,849 facilitated by ketamine. The median drug doses were 0.28 mg/kg (interquartile range [IQR] 0.22 mg/kg to 0.32 mg/kg) for etomidate and 1.33 mg/kg (IQR 1 mg/kg to 1.8 mg/kg) for ketamine. Postintubation hypotension occurred in 1,976 patients (16.2%) who received etomidate and in 537 patients (29.0%) who received ketamine. In multivariable models, neither the etomidate dose (adjusted odds ratio [aOR] 0.95, 95% confidence interval [CI] 0.90 to 1.01) nor ketamine dose (aOR 0.97, 95% CI 0.81 to 1.17) was associated with postintubation hypotension. Results were similar in sensitivity analyses excluding patients with preintubation hypotension and including only patients intubated for shock.

CONCLUSION

In this large registry of patients intubated after receiving either etomidate or ketamine, we observed no association between the weight-based sedative dose and postintubation hypotension.

Preoperative shock index in major abdominal emergency surgery

Introduction

Major abdominal emergency surgery (MAES) patients have a high risk of mortality and complications. The time-sensitive nature of MAES necessitates an easily calculable risk-scoring tool. Shock index (SI) is obtained by dividing heart rate (HR) by systolic blood pressure (SBP) and provides insight into a patient's haemodynamic status. We aimed to evaluate SI's usefulness in predicting postoperative mortality, acute kidney injury (AKI), requirements for intensive care unit (ICU) and high-dependency monitoring, and the ICU length of stay (LOS).

Method

We retrospectively reviewed 212,089 MAES patients from January 2013 to December 2020. The cohort was propensity matched, and 3960 patients were included. The first HR and SBP recorded in the anaesthesia chart were used to calculate SI. Regression models were used to investigate the association between SI and outcomes. The relationship between SI and survival was explored with Kaplan-Meier curves.

Results

There were significant associations between SI and mortality at 1 month (odds ratio [OR] 2.40 [1.67-3.39], P<0.001), 3 months (OR 2.13 [1.56-2.88], P<0.001), and at 2 years (OR 1.77 [1.38-2.25], P<0.001). Multivariate analysis revealed significant relationships between SI and mortality at 1 month (OR 3.51 [1.20-10.3], P=0.021) and at 3 months (OR 3.05 [1.07-8.54], P=0.034). Univariate and multivariate analysis also revealed significant relationships between SI and AKI (P<0.001), postoperative ICU admission (P<0.005) and ICU LOS (P<0.001). SI does not significantly affect 2-year mortality.

Conclusion

SI is useful in predicting postopera-tive mortality at 1 month, 3 months, AKI, postoperative ICU admission and ICU LOS.

Prophylactic Administration of Vasopressors Prior to Emergency Intubation in Critically Ill Patients: A Secondary Analysis of Two Multicenter Clinical Trials

Hypotension affects approximately 40% of critically ill patients undergoing emergency intubation and is associated with an increased risk of death. The objective of this study was to examine the association between prophylactic vasopressor administration and the incidence of peri-intubation hypotension and other clinical outcomes.

DESIGN

A secondary analysis of two multicenter randomized clinical trials. The clinical effect of prophylactic vasopressor administration was estimated using a one-to-one propensity-matched cohort of patients with and without prophylactic vasopressors.

SETTING

Seven emergency departments and 17 ICUs across the United States.

PATIENTS

One thousand seven hundred ninety-eight critically ill patients who underwent emergency intubation at the study sites between February 1, 2019, and May 24, 2021.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was peri-intubation hypotension defined as a systolic blood pressure less than 90 mm Hg occurring between induction and 2 minutes after tracheal intubation. A total of 187 patients (10%) received prophylactic vasopressors prior to intubation. Compared with patients who did not receive prophylactic vasopressors, those who did were older, had higher Acute Physiology and Chronic Health Evaluation II scores, were more likely to have a diagnosis of sepsis, had lower pre-induction systolic blood pressures, and were more likely to be on continuous vasopressor infusions prior to intubation. In our propensity-matched cohort, prophylactic vasopressor administration was not associated with reduced risk of peri-intubation hypotension (41% vs 32%; p = 0.08) or change in systolic blood pressure from baseline (-12 vs -11 mm Hg; p = 0.66).

CONCLUSIONS

The administration of prophylactic vasopressors was not associated with a lower incidence of peri-intubation hypotension in our propensity-matched analysis. To address potential residual confounding, randomized clinical trials should examine the effect of prophylactic vasopressor administration on peri-intubation outcomes.

Clinical outcomes after a single induction dose of etomidate versus ketamine for emergency department sepsis intubation: a randomized controlled trial

Patients with sepsis often require emergency intubation. In emergency departments (EDs), rapid-sequence intubation with a single-dose induction agent is standard practice, but the best choice of induction agent in sepsis remains controversial. We conducted a randomized, controlled, single-blind trial in the ED. We included septic patients who were aged at least 18 years and required sedation for emergency intubation. Patients were randomly assigned by a blocked randomization to receive 0.2-0.3 mg/kg of etomidate or 1-2 mg/kg of ketamine for intubation. The objectives were to compare the survival outcomes and adverse events after intubation between etomidate and ketamine. Two hundred and sixty septic patients were enrolled; 130 patients/drug arm whose baseline characteristics were well balanced at baseline. In the etomidate group, 105 patients (80.8%) were alive at 28 days, compared with 95 patients (73.1%) in the ketamine group (risk difference [RD], 7.7%; 95% confidence interval [CI], - 2.5 to 17.9%; P = 0.092). There was no significant difference in the proportion of patients who survived at 24 h (91.5% vs. 96.2%; P = 0.097) and survived at 7 days (87.7% vs. 87.7%; P = 0.574). A significantly higher proportion of the etomidate group needed a vasopressor within 24 h after intubation: 43.9% vs. 17.7%, RD, 26.2% (95% CI, 15.4 to 36.9%; P < 0.001). In conclusion, there were no differences in early and late survival rates between etomidate and ketamine. However, etomidate was associated with higher risks of early vasopressor use after intubation. Trial registration: The trial protocol was registered in the Thai Clinical Trials Registry (identification number: TCTR20210213001). Registered 13 February 2021-Retrospectively registered, https://www.thaiclinicaltrials.org/export/pdf/TCTR20210213001 .

Managing the Physiologically Difficult Airway in Critically Ill Adults

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2023. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2023 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from  https://link.springer.com/bookseries/8901 .

Endotracheal intubation in trauma patients with isolated shock: universally recommended but rarely performed

PURPOSE

The indication for pre-hospital endotracheal intubation (ETI) must be well considered as it is associated with several risks and complications. The current guidelines recommend, among other things, ETI in case of shock (systolic blood pressure < 90 mmHg). This study aims to investigate whether isolated hypotension without loss of consciousness is a useful criterion for ETI.

METHODS

The data of 37,369 patients taken from the TraumaRegister DGU® were evaluated in a retrospective study with regard to pre-hospital ETI and the underlying indications. Inclusion criteria were the presence of any relevant injuries (Abbreviated Injury Scale [AIS] ≥ 3) and complete pre-hospital management information.

RESULTS

In our cohort, 29.6% of the patients were intubated. The rate of pre-hospital ETI increased with the number of indications. If only one criterion according to current guidelines was present, ETI was often omitted. In 582 patients with shock as the only indication for pre-hospital ETI, only 114 patients (19.6%) were intubated. Comparing these subgroups, the intervention was associated with longer time on scene (25.3 min vs. 41.6 min; p < 0.001), higher rate of coagulopathy (31.8% vs. 17.2%), an increased mortality (8.2% vs. 11.5%) and higher standard mortality ratio (1.17 vs. 1.35). If another intubation criterion was present in addition to shock, intubation was performed more frequently.

CONCLUSION

Decision making for pre-hospital intubation in trauma patients is challenging in front of a variety of factors. Despite the presence of a guideline recommendation, ETI is not always executed. Patients presenting with shock as remaining indication and subsequent intubation showed a decreased outcome. Thus, isolated shock does not appear to be an appropriate indication for pre-hospital ETI, but clearly remains an important surrogate of trauma severity and the need for trauma team activation.

Ketamine is not associated with more post-intubation hypotension than etomidate in patients undergoing endotracheal intubation

INTRODUCTION

Emergency department (ED) patients undergoing emergent tracheal intubation often have multiple physiologic derangements putting them at risk for post-intubation hypotension. Prior work has shown that post-intubation hypotension is independently associated with increased morbidity and mortality. The choice of induction agent may be associated with post-intubation hypotension. Etomidate and ketamine are two of the most commonly used agents in the ED, however, there is controversy regarding whether either agent is superior in the setting of hemodynamic instability. The goal of this study is to determine whether there is a difference in the rate of post-intubation hypotension who received either ketamine or etomidate for induction. Additionally, we provide a subgroup analysis of patients at pre-existing risk of cardiovascular collapse (identified by pre-intubation shock index (SI) > 0.9) to determine if differences in rates of post-intubation hypotension exist as a function of sedative choice administered during tracheal intubation in these high-risk patients. We hypothesize that there is no difference in the incidence of post-intubation hypotension in patients who receive ketamine versus etomidate.

METHODS

A retrospective cohort study was conducted on a database of 469 patients having undergone emergent intubation with either etomidate or ketamine induction at a large academic health system. Patients were identified by automatic query of the electronic health records from 1/1/2016-6/30/2019. Exclusion criteria were patients <18-years-old, tracheal intubation performed outside of the ED, incomplete peri-intubation vital signs, or cardiac arrest prior to intubation. Patients at high risk for hemodynamic collapse in the post-intubation period were identified by a pre-intubation SI > 0.9. The primary outcome was the incidence of post-intubation hypotension (systolic blood pressure < 90 mmHg or mean arterial pressure < 65 mmHg). Secondary outcomes included post-intubation vasopressor use and mortality. These analyses were performed on the full cohort and an exploratory analysis in patients with SI > 0.9. We also report adjusted odds ratios (aOR) from a multivariable logistic regression model of the entire cohort controlling for plausible confounding variables to determine independent factors associated with post-intubation hypotension.

RESULTS

A total of 358 patients were included (etomidate: 272; ketamine: 86). The mean pre-intubation SI was higher in the group that received ketamine than etomidate, (0.97 vs. 0.83, difference: -0.14 (95%, CI -0.2 to -0.1). The incidence of post-intubation hypotension was greater in the ketamine group prior to SI stratification (difference: -10%, 95% CI -20.9% to -0.1%). Emergency physicians were more likely to use ketamine in patients with SI > 0.9. In our multivariate logistic regression analysis, choice of induction agent was not associated with post-intubation hypotension (aOR 1.45, 95% CI 0.79 to 2.65). We found that pre-intubation shock index was the strongest predictor of post-intubation hypotension.

CONCLUSION

In our cohort of patients undergoing emergent tracheal intubation, ketamine was used more often for patients with an elevated shock index. We did not identify an association between the incidence of post-intubation hypotension and induction agent between ketamine and etomidate. Patients with an elevated shock index were at higher risk of cardiovascular collapse regardless of the choice of ketamine or etomidate.

Design and Implementation of Airway Response Teams to Improve the Practice of Emergency Airway Management

Emergency airway management (EAM) is a commonly performed procedure in the critical care setting. Despite clinical advances that help practitioners identify patients at risk for having a difficult airway, improved airway management tools, and algorithms that guide clinical decision-making, the practice of EAM is associated with significant morbidity and mortality. Evidence suggests that a dedicated airway response team (ART) can help mitigate the risks associated with EAM and provide a framework for airway management in acute settings. We review the risks and challenges related to EAM and describe strategies to improve patient care and outcomes via implementation of an ART.

The safety and efficacy of push dose vasopressors in critically ill adults

PURPOSE

To evaluate practice patterns, efficacy, and safety of push dose pressors (PDP) in critically ill patients outside of the operating room (OR) at a large academic medical center.

MATERIALS AND METHODS

This was a single-center, retrospective cohort study (June 2018 to July 2020) conducted at a 1273-bed academic medical center. The primary outcome was efficacy, defined as a 25% increase in systolic blood pressure, and the cohort was analyzed according to PDP response (i.e. responders versus non-responders). A logistic regression model was used to assess predictors of response to PDPs. Safety outcomes included the incidence of hypertension, bradycardia, and tachycardia.

RESULTS

1727 patients were included in the final analysis. The median doses of phenylephrine and epinephrine administered were 400 μg (IQR 200-888 μg) and 50 μg (IQR 20-100 μg). The primary outcome was achieved in 102 (71.8%) patients in the epinephrine group and 1140 (55.9%) of patients in the phenylephrine group. Adverse effects after PDP receipt were minimal, with the most common being hypertension in 6.6% and 13.4% of the phenylephrine and epinephrine groups respectively.

CONCLUSIONS

This study demonstrates that PDP phenylephrine and epinephrine are safe and efficacious in treating the acute hypotensive period.

Peripheral tissue hypoperfusion predicts post intubation hemodynamic instability

Background

Tracheal intubation and invasive mechanical ventilation initiation is a procedure at high risk for arterial hypotension in intensive care unit. However, little is known about the relationship between pre-existing peripheral microvascular alteration and post-intubation hemodynamic instability (PIHI).

Methods

Prospective observational monocenter study conducted in an 18-bed medical ICU. Consecutive patients requiring tracheal intubation were eligible for the study. Global hemodynamic parameters (blood pressure, heart rate, cardiac function) and tissue perfusion parameters (arterial lactate, mottling score, capillary refill time [CRT], toe-to-room gradient temperature) were recorded before, 5 min and 2 h after tracheal intubation (TI). Post intubation hemodynamic instability (PIHI) was defined as any hemodynamic event requiring therapeutic intervention.

Results

During 1 year, 120 patients were included, mainly male (59%) with a median age of 68 [57–77]. The median SOFA score and SAPS II were 6 [4–9] and 47 [37–63], respectively. The main indications for tracheal intubation were hypoxemia (51%), hypercapnia (13%), and coma (29%). In addition, 48% of patients had sepsis and 16% septic shock. Fifty-one (42%) patients develop PIHI. Univariate analysis identified several baseline factors associated with PIHI, including norepinephrine prior to TI, sepsis, tachycardia, fever, higher SOFA and high SAPSII score, mottling score ≥ 3, high lactate level and prolonged knee CRT. By contrast, mean arterial pressure, baseline cardiac index, and ejection fraction were not different between PIHI and No-PIHI groups. After adjustment on potential confounders, the mottling score was associated with a higher risk for PIHI (adjusted OR: 1.84 [1.21–2.82] per 1 point increased; p = 0.005). Among both global haemodynamics and tissue perfusion parameters, baseline mottling score was the best predictor of PIHI (AUC: 0.72 (CI 95% [0.62–0.81]).

Conclusions

In non-selected critically ill patients requiring invasive mechanical ventilation, tissue hypoperfusion parameters, especially the mottling score, could be helpful to predict PIHI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01043-3.

Independent risk factors of mortality in patients with sepsis receiving single-dose etomidate as an induction agent during rapid sequence intubation in a large tertiary emergency department in Thailand

BACKGROUND

There is limited evidence regarding factors associated with mortality in septic patients receiving etomidate. This study aimed to determine independent pre-intubation factors predicting 28-day mortality in septic patients receiving single-dose etomidate as an induction agent during rapid sequence intubation (RSI).

METHODS

This single-center retrospective cohort study included intubated septic patients receiving etomidate as an induction agent during RSI in the emergency department of Siriraj hospital, Bangkok, Thailand, between January 1st, 2016 and June 30th, 2020. Pre-intubation characteristics were compared between survivors and non-survivors. Independent risk factors associated with 28-day mortality were identified using the Cox proportional hazards regression model. Association between etomidate dosage and mortality was also determined.

RESULTS

A total of 344 patients, 238 (69%) survivors and 106 (31%) non-survivors, were included in the analyses. The initial Cox hazards model identified a pre-intubation lactate level ≥ 4 mmol/L as an independent factor associated with mortality (adjusted Hazards ratio [aHR] 2.66, 95% confidence interval [CI] 1.55-4.56). After removing lactate level from the model due to limited lactate values in the data, cancer was also predictive of 28-day mortality (aHR 1.83, 95%CI 1.10-3.04), while patients with respiratory infections and underlying chronic lung disease were associated with lower mortality (aHR 0.54, 95%CI 0.37-0.80 and aHR 0.57, 0.33-0.96, respectively). Etomidate dosage was not associated with mortality in our study.

CONCLUSION

In septic patients who received a single dose of etomidate, a pre-intubation lactate level ≥ 4 mmol/L and cancer were associated with increased 28-day mortality, while respiratory infection and underlying chronic lung disease were associated with lower mortality. Physicians may take these factors into consideration when selecting induction agents for septic patients.

Tracheal intubation in the critically ill patient

Tracheal intubation is among the most commonly performed and high-risk procedures in critical care. Indeed, 45% of patients undergoing intubation experience at least one major peri-intubation adverse event, with cardiovascular instability being the most common event reported in 43%, followed by severe hypoxemia in 9% and cardiac arrest in 3% of cases. These peri-intubation adverse events may expose patients to a higher risk of 28-day mortality, and they are more frequently observed with an increasing number of attempts to secure the airway. The higher risk of peri-intubation complications in critically ill patients, compared with the anaesthesia setting, is the consequence of their deranged physiology (e.g. underlying respiratory failure, shock and/or acidosis) and, in this regard, airway management in critical care has been defined as "physiologically difficult". In recent years, several randomised studies have investigated the most effective preoxy-genation strategies, and evidence for the use of positive pressure ventilation in moderate-to-severe hypoxemic patients is established. On the other hand, evidence on interventions to mitigate haemodynamic collapse after intubation has been elusive. Airway management in COVID-19 patients is even more challenging because of the additional risk of infection for healthcare workers, which has influenced clinical choices in this patient group. The aim of this review is to provide an update of the evidence for intubation in critically ill patients with a focus on understanding peri-intubation risks and evaluating interventions to prevent or mitigate adverse events.

Safety of Propofol When Used for Rapid Sequence Intubation in Septic Patients: A Multicenter Cohort Study

Purpose

Septic patients are at risk for hypotension, and this risk may increase during rapid sequence intubation (RSI). Sedatives such as propofol must be used carefully due to its ability to reduce vascular sympathetic tone. Since the safety of propofol for RSI is not well described in sepsis, this was a study evaluating propofol and its effects on hemodynamics when used for RSI in a septic population.

Materials and methods

We conducted a multicenter, retrospective, cohort study of patients with sepsis or severe sepsis requiring sedation for RSI. Patients receiving a propofol bolus for RSI were compared to patients undergoing RSI without a propofol bolus. The safety profile of propofol was evaluated according to the rates of post-intubation hypotension and vasopressor utilization between groups.

Results

A total of 179 patients (79 propofol, 100 non-propofol) were evaluated. There were no differences in hypotension (81% vs 78%; P = .62) or vasopressor utilization between the propofol and non-propofol groups (43% vs 49%; P = .43). Patients in the non-propofol group had increased APACHE II scores and healthcare-associated infections.

Conclusions

In this cohort study, administration of propofol for RSI in patients with sepsis and severe sepsis did not increase incidence of hypotension or vasopressor use, but acute illness may have introduced provider selection bias causing less propofol use in the non-propofol group. Larger prospective studies are needed to better characterize the adverse hemodynamic effects of propofol, before propofol bolus doses for RSI can be considered for safe use in this population.

The physiologically difficult airway: an emerging concept

PURPOSE OF REVIEW

The physiologically difficult airway is one in which physiologic alterations in the patient increase the risk for cardiorespiratory and other complications during tracheal intubation and transition to positive pressure ventilation. This review will summarize the recent literature around the emerging concept of the physiologically difficult airway, describe its relevance and various patient types in which this entity is observed.

RECENT FINDINGS

Physiologic derangements during airway management occur due acute illness, pre-existing disease, effects of anesthetic agents, and positive pressure ventilation. These derangements are especially recognized in critically ill patients, but can also occur in otherwise healthy patients including obese, pregnant and pediatric patients who have certain physiological alterations. Critically ill patients may have a physiologically difficult airway due to the presence of acute respiratory failure, hypoxemia, hypotension, severe metabolic acidosis, right ventricular failure, intracranial hypertension, and risk of aspiration of gastric contents during tracheal intubation.

SUMMARY

Understanding the physiological alterations and the risks involved in patients with a physiologically difficult airway is necessary to optimize the physiology and adopt strategies to avoid complications during tracheal intubation. Further research will help us better understand the optimal strategies to improve outcomes in these patients.

Hemodynamics in Helicopter Emergency Medical Services (HEMS) Patients Undergoing Rapid Sequence Intubation With Etomidate or Ketamine

BACKGROUND

Rapid sequence intubation (RSI) is performed by helicopter emergency medical services (HEMS) providers to establish airway control. Common induction agents are etomidate and ketamine, both touted to have relatively stable hemodynamic profiles. Limited data comparing these medications in the air medical setting exist.

OBJECTIVE

Compare administration of ketamine and etomidate on peri-intubation hemodynamics.

METHODS

A retrospective chart review of intubations performed by a HEMS program over 69 months was completed. Heart rate (HR) change, systolic blood pressure (SBP) change, and hypotension with etomidate or ketamine use were measured.

RESULTS

There were 258 patients induced with etomidate and 48 with ketamine. Etomidate patients showed a +1.161% change in HR (SD ± 22.7) and -0.49% change in SBP (SD ± 25.0). Ketamine patients showed a -4.7% change in HR (SD ± 16.7) and 17.2% change in SBP (SD ± 43.4). The p-values for percentage change in HR and SBP between etomidate and ketamine were 0.0830 and 0.0018, respectively. Twenty-five episodes of postadministration hypotension occurred with etomidate, and two with ketamine (p = 0.028).

CONCLUSION

Both ketamine and etomidate are appropriate for intubation of HEMS patients. Ketamine was preferentially selected for hypotensive patients with statistically significant improvement in SBP. Although statistically significant, both ketamine and etomidate had relative low incidences of hypotension.

Rapid Intubation Sequence: 4-Year Experience in an Emergency Department

Background

The rapid intubation sequence is advanced airway management that effectively ensures an adequate supply of oxygen in critically ill patients. The medical personnel in the emergency department performed this procedure.

Objective

To describe the main characteristics of the rapid intubation sequence in an emergency department of a high complexity hospital.

Methods

This is a descriptive, cross-sectional, retrospective study. We included all older patients with a rapid intubation sequence requirement in the emergency department from 2014 to 2017. We used central tendency measures for numerical variables and proportions for categorical variables.

Results

A total of 401 patients were eligible for this analysis. The main indication for intubation was the Glasgow Coma Scale = <8 in 170 patients (42.4%), followed by hypoxemia in 142 patients (35.4%). In 36 patients, at least one complication occurred. RSI was performed in 54.4% by emergency physician. RSI was successful on the first attempt in 90.5%. Only 36 patients (9%) presented complications.

Conclusion

In this study, we found that the rapid intubation sequence was not related to a high proportion of complications. Perhaps, this is attributed to the degree of medical training and the use of emergency department protocols in our hospital.

Mapping haemodynamic changes with rapid sequence induction agents in the emergency department

OBJECTIVE

Patients intubated in the ED are at an increased risk of post-intubation hypotension. However, evidence regarding the most appropriate induction agent is lacking. The present study aims to describe and compare the haemodynamic effect of propofol, ketamine and thiopentone during rapid sequence induction.

METHODS

This is an observational study using data prospectively collected from the Australian and New Zealand Emergency Department Airway Registry between June 2012 and March 2019. The distribution of induction agents across medical and trauma patients were obtained with descriptive statistics. The relationship between induction agent, dose and change in pre- and post-intubation systolic blood pressure (SBP) was described using multivariable logistic regression. The SBP pre- and post-intubation was the primary measure of haemodynamic stability.

RESULTS

From the 5063 intubation episodes, 2229 met the inclusion criteria. Of those, 785 (35.2%) patients were induced with thiopentone, 773 (34.7%) with propofol and 671 (30.1%) with ketamine. Of the included population, 396 (17.8%) patients experienced a reduction in pre-intubation SBP exceeding 20%. Both propofol (P = 0.01) and ketamine (P = 0.01) had an independent and dose-dependent association with hypotension, noting that a higher proportion of patients induced with ketamine had a shock index exceeding 0.9.

CONCLUSION

Propofol was associated with post-intubation hypotension and it is recommended clinicians consider using the lowest effective dose to reduce this risk. Reflecting its perceived haemodynamic stability, patients who received ketamine were more likely to have a higher shock index; however, there was also an association with post-intubation hypotension.

Complications during repeated tracheal intubation in the Intensive Care Unit. A prospective, observational study comparing the first intubation and the reintubation

BACKGROUND AND GOAL OF THE STUDY

The goal of the study was to compare the incidence of complications, technical difficulty of intubation and physiologic pre-intubation status between the first intubation and reintubation performed on the same patient in an ICU.

MATERIALS AND METHODS

The study was approved by the ethics committee of Galicia (Santiago-Lugo, code No. 2015-012). Due to the observational, noninterventional, and noninvasive design of this study, the need for written consent was waived by the ethics committee of Galicia. Patients requiring tracheal intubation and reintubation in the ICU were included in this prospective observational study. Main endpoint was to compare the incidence of complications, physiologic pre-intubation status, and the rate of technical difficulty of intubation between the first intubation and reintubation performed on the same patient in an ICU.

RESULTS AND DISCUSSION

504 patients were intubated in our ICU during the study period, and 82 (16%) required reintubation. There was no difference between the first intubation and reintubation regarding number of total complication (35% vs 33%; P = ,86), hypotension (24% vs 24%; P = 1), hypoxia (26% vs 26%; P = 1), esophageal intubation (1% vs 1%; P = 1), and bronchoaspiration (2% vs 1%; P = ,86). Physiologic pre-intubation status and technical difficulty of intubation did not differ between the first intubation and reintubation.

CONCLUSIONS

In our ICU patients requiring tracheal reintubation, incidence of complications, physiologic pre-intubation status, and technical difficulty of intubation did not differ between the first intubation and reintubation.

Emergency Airway Management Outside the Operating Room: Current Evidence and Management Strategies

Emergency airway management outside the operating room (OR) is often associated with an increased risk of airway related, as well as cardiopulmonary, complications which can impact morbidity and mortality. These emergent airways may take place in the intensive care unit (ICU), where patients are critically ill with minimal physiological reserve, or other areas of the hospital where advanced equipment and personnel are often unavailable. As such, emergency airway management outside the OR requires expertise at manipulation of not only the anatomically difficult airway but also the physiologically and situationally difficult airway. Adequate preparation and appropriate use of airway management techniques are important to prevent complications. Judicious utilization of pre- and apneic oxygenation is important as is the choice of medications to facilitate intubation in this at-risk population. Recent study in critically ill patients has shown that postintubation hemodynamic and respiratory compromise is common, independently associated with poor outcomes and can be impacted by the choice of drugs and techniques used. In addition to adequately preparing for a physiologically difficult airway, enhancing the ability to predict an anatomically difficult airway is essential in reducing complication rates. The use of artificial intelligence in the identification of difficult airways has shown promising results and could be of significant advantage in uncooperative patients as well as those with a questionable airway examination. Incorporating this technology and understanding the physiological, anatomical, and logistical challenges may help providers better prepare for managing such precarious airways and lead to successful outcomes. This review discusses the various challenges associated with airway management outside the OR, provides guidance on appropriate preparation, airway management skills, medication use, and highlights the role of a coordinated multidisciplinary approach to out-of-OR airway management.

Definition and incidence of hypotension in intensive care unit patients, an international survey of the European Society of Intensive Care Medicine

INTRODUCTION

Although hypotension in ICU patients is associated with adverse outcome, currently used definitions are unknown and no universally accepted definition exists.

METHODS

We conducted an international, peer-reviewed survey among ICU physicians and nurses to provide insight in currently used definitions, estimations of incidence, and duration of hypotension.

RESULTS

Out of 1394 respondents (1055 physicians (76%) and 339 nurses (24%)), 1207 (82%) completed the questionnaire. In all patient categories, hypotension definitions were predominantly based on an absolute MAP of 65 mmHg, except for the neuro(trauma) category (75 mmHg, p < 0.001), without differences between answers from physicians and nurses. Hypotension incidence was estimated at 55%, and time per day spent in hypotension at 15%, both with nurses reporting higher percentages than physicians (estimated mean difference 5%, p = 0.01; and 4%, p < 0.001).

CONCLUSIONS

An absolute MAP threshold of 65 mmHg is most frequently used to define hypotension in ICU patients. In neuro(trauma) patients a higher threshold was reported. The majority of ICU patients are estimated to endure hypotension during their ICU admission for a considerable amount of time, with nurses reporting a higher estimated incidence and time spent in hypotension than physicians.

Intraoperative hypotension and complications after vascular surgery: A scoping review

BACKGROUND

Intraoperative hypotension during major surgery is associated with adverse health outcomes. This phenomenon represents a potentially important therapeutic target for vascular surgery patients, who may be uniquely vulnerable to intraoperative hypotension. This review summarizes current evidence regarding the impact of intraoperative hypotension on postoperative complications in patients undergoing vascular surgery, focusing on potentially modifiable procedure- and patient-specific risk factors.

METHODS

A scoping review of the literature from Embase, MEDLINE, and PubMed databases was conducted from inception to December 2019 to identify articles related to the effects of intraoperative hypotension on patients undergoing vascular surgery.

RESULTS

Ninety-two studies met screening criteria; 9 studies met quality and inclusion criteria. Among the 9 studies that defined intraoperative hypotension objectively, there were 9 different definitions. Accordingly, the reported incidence of intraoperative hypotension ranged from 8% to 88% (when defined as a fall in systolic blood pressure of >30 mm Hg or mean arterial pressure <65). The results demonstrated that intraoperative hypotension is an independent risk factor for longer hospital length of stay, myocardial injury, acute kidney injury, postoperative mechanical ventilation, and early mortality. Vascular surgery patients with comorbid conditions that confer increased vulnerability to hypoperfusion and ischemia appear to be susceptible to the adverse effects of intraoperative hypotension.

CONCLUSION

There is no validated, consensus definition of intraoperative hypotension or other hemodynamic parameters associated with increased risk for adverse outcomes. Despite these limitations, the weight of evidence suggests that intraoperative hypotension is common and associated with major postoperative complications in vascular surgery patients.

Airway Management in the Critically Ill Patient

Purpose of Review

This paper will evaluate the recent literature and best practices in airway management in critically ill patients.

Recent Findings

Cardiac arrest remains a common complication of intubation in these high-risk patients. Patients with desaturation or peri-intubation hypotension are at high risk of cardiac arrest, and each of these complications have been reported in up to half of all intubations in critically ill patient populations.

Summary

There have been significant advances in preoxygenation and devices available for performing laryngoscopy and rescue oxygenation. However, the risk of cardiovascular collapse remains concerningly high with few studies to guide therapeutic maneuvers to reduce this risk.

Evaluation and Management of the Physiologically Difficult Airway: Consensus Recommendations From Society for Airway Management

Multiple international airway societies have created guidelines for the management of the difficult airway. In critically ill patients, there are physiologic derangements beyond inadequate airway protection or hypoxemia. These risk factors contribute to the "physiologically difficult airway" and are associated with complications including cardiac arrest and death. Importantly, they are largely absent from international guidelines. Thus, we created management recommendations for the physiologically difficult airway to provide practical guidance for intubation in the critically ill. Through multiple rounds of in-person and telephone conferences, a multidisciplinary working group of 12 airway specialists (Society for Airway Management's Special Projects Committee) over a time period of 3 years (2016-2019) reviewed airway physiology topics in a modified Delphi fashion. Consensus agreement with the following recommendations among working group members was generally high with 80% of statements showing agreement within a 10% range on a sliding scale from 0% to 100%. We limited the scope of this analysis to reflect the resources and systems of care available to out-of-operating room adult airway providers. These recommendations reflect the practical application of physiologic principles to airway management available during the analysis time period.

Ketamine Versus Etomidate and Peri-intubation Hypotension: A National Emergency Airway Registry Study

BACKGROUND

The hemodynamic impact of induction agents is a critically important consideration in emergency intubations. We assessed the relationship between peri-intubation hypotension and the use of ketamine versus etomidate as an induction agent for emergency department (ED) intubation.

METHODS

We analyzed ED intubation data for patients aged >14 years from the National Emergency Airway Registry performed in 25 EDs during 2016 through 2018. We excluded patients with preintubation hypotension (systolic blood pressure <100 mm Hg) or cardiac arrest prior to intubation. The primary outcome was peri-intubation hypotension. Secondary outcomes included interventions for hypotension (e.g., intravenous fluids or vasopressors). We report adjusted odds ratios (aOR) from multivariable logistic regression models controlling for patient demographics, difficult airway characteristics, and intubation modality.

RESULTS

There were 738 encounters with ketamine and 6,068 with etomidate. Patients receiving ketamine were more likely to have difficult airway characteristics (effect size difference = 8.8%, 95% confidence interval [CI] = 5.3% to 12.4%) and to undergo intubation with video laryngoscopy (8.1%, 95% CI = 4.4% to 12.0%). Peri-intubation hypotension incidence was 18.3% among patients receiving ketamine and 12.4% among patients receiving etomidate (effect size difference = 5.9%, 95% CI = 2.9% to 8.8%). Patients receiving ketamine were more likely to receive treatment for peri-intubation hypotension (effect size difference = 6.5%, 95% CI = 3.9% to 9.3%). In logistic regression analyses, patients receiving ketamine remained at higher risk for peri-intubation hypotension (aOR = 1.4, 95% CI = 1.2 to 1.7) and treatment for hypotension (aOR = 1.8, 95% CI = 1.4 to 2.0). There was no difference in the aOR of hypotension between patients receiving ketamine at doses ≤1.0 mg/kg versus >1.0 mg/kg or patients receiving etomidate at doses ≤0.3 mg/kg versus >0.3 mg/kg.

CONCLUSIONS

Pending additional data, our results suggest that clinicians should not necessarily prioritize ketamine over etomidate based on concern for hemodynamic compromise among ED patients undergoing intubation.

Etomidate Use Is Associated With Less Hypotension Than Ketamine for Emergency Department Sepsis Intubations: A NEAR Cohort Study

OBJECTIVE

The objectives of this study were 1) to describe the current use of etomidate and other induction agents in patients with sepsis and 2) to compare adverse events between etomidate and ketamine in sepsis.

METHODS

This was an observational cohort study of the prospective National Emergency Airway Registry (NEAR) data set. Descriptive statistics were used to report the distribution of induction agents used in patients with sepsis. Adverse events were compared using bivariate analysis, and a sensitivity analysis was conducted using a propensity score-adjusted analysis of etomidate versus ketamine.

RESULTS

A total of 531 patients were intubated for sepsis, and the majority (71%) were intubated with etomidate as the initial induction agent. Etomidate was less frequently used in sepsis patients than nonsepsis patients (71% vs. 85%, odds ratio [OR] = 0.4, 95% confidence interval [CI] = 0.4 to 0.5). Sepsis patients had a greater risk of adverse events, and vasopressor therapy was required for 25% of patients after intubation. Postprocedure hypotension was higher between those intubated for sepsis with ketamine versus etomidate (74% vs. 50%, OR = 2.9, 95% CI = 1.9 to 4.5). After confounding by indication in the propensity score-adjusted analysis was accounted for, ketamine was associated with more postprocedure hypotension (OR = 2.7, 95% CI = 1.1 to 6.7). No difference in emergency department deaths was observed.

CONCLUSIONS

Etomidate is used less frequently in sepsis patients than nonsepsis patients, with ketamine being the most frequently used alternative. Ketamine was associated with more postprocedural hypotension than etomidate. Future clinical trials are needed to determine the optimal induction agent in patients with sepsis.

Risk Factors for and Outcomes Associated With Peri-Intubation Hypoxemia: A Multicenter Prospective Cohort Study

BACKGROUND

Little is known about hypoxemia surrounding endotracheal intubation in the critically ill. Thus, we sought to identify risk factors associated with peri-intubation hypoxemia and its effects' on the critically ill.

METHODS

Data from a multicenter, prospective, cohort study enrolling 1,033 critically ill adults who underwent endotracheal intubation across 16 medical/surgical ICUs in the United States from July 2015-January 2017 were used to identify risk factors associated with peri-intubation hypoxemia and its effects on patient outcomes. We defined hypoxemia as any pulse oximetry ≤ 88% during and up to 30 minutes following endotracheal intubation.

RESULTS

In the full analysis (n = 1,033), 123 (11.9%) patients experienced the primary outcome. Five risk factors independently associated with our outcome were identified on multiple logistic regression: cardiac related reason for endotracheal intubation (OR 1.67, [95% CI 1.04, 2.69]); pre-intubation noninvasive ventilation (OR 1.66, [95% CI 1.09, 2.54]); emergency intubation (OR 1.65, [95% CI 1.06, 2.55]); moderate-severe difficult bag-mask ventilation (OR 2.68, [95% CI 1.72, 4.19]); and crystalloid administration within the preceding 24 hours (OR 1.24, [95% CI 1.07, 1.45]; per liter up to 4 liters). Higher baseline S_pO₂ was found to be protective (OR 0.93, [95% CI 0.91, 0.96]; per percent up to 97%). Consistent results were seen in a separate analysis on only stable patients (n = 921, 93 [10.1%]) (those without baseline hypoxemia ≤ 88%). Peri-intubation hypoxemia was associated with in-hospital mortality (OR 2.40, [95% CI 1.33, 4.31]; stable patients: OR 2.67, [95% CI 1.38, 5.17]) but not ICU length of stay (point estimate 0.9 days, [95% CI -1.0, 2.8 days]; stable patients: point estimate 1.5 days, [95% CI -0.4, 3.4 days]) after adjusting for age, body mass index, illness severity, airway related reason for intubation (i.e., acute respiratory failure), and baseline S_PO₂.

CONCLUSIONS

Patients with pre-existing noninvasive ventilation and volume loading who were intubated emergently in the setting of hemodynamic compromise with bag-mask ventilation described as moderate-severe were at increased risk for peri-intubation hypoxemia. Higher baseline oxygenation was found to be protective against peri-intubation hypoxemia. Peri-intubation hypoxemia was associated with in-hospital mortality but not ICU length of stay.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT02508948 and Registered Report Identifier: RR2-10.2196/11101.

The critical care literature 2019

An emergency physician (EP) is often the first health care provider to evaluate, resuscitate, and manage a critically ill patient. In recent years, the annual hours of critical care delivered in emergency departments across the United States has steadily increased. From 2006 to 2014, emergency department (ED) visits for critically ill patients increased approximately 80%. In addition to seeing more critically ill patients, EPs are often tasked with providing critical care long beyond the initial resuscitation period. In fact, more than 50% of ED patients that require admission to the ICU remain in the ED for more than 6 h. Prolonged ED wait times for critically ill patients to be transferred to the ICU is associated with increased hospital, 30-day, and 90-day mortality. It is during these early hours of critical illness, while the patient is in the ED, where lives can be saved or lost. Therefore, it is important for the EP to be knowledgeable about recent developments in resuscitation and critical care medicine. This review summarizes important articles published in 2019 pertaining to the resuscitation and care of select critically ill patients. We chose these articles based on our opinion of the importance of the study findings and their application to emergency medicine. The following topics are covered: sepsis, rapid sequence intubation, mechanical ventilation, neurocritical care, post-cardiac arrest care, and ED-based ICUs.

What is the Role of Sugammadex in the Emergency Department?

BACKGROUND

Sugammadex is a medication newly available to many emergency physicians. It effectively, and within minutes, reverses neuromuscular blockade in patients who have received rocuronium or vecuronium. The role of sugammadex for the reversal of neuromuscular blockade after rapid sequence intubation in the emergency department (ED) is evolving, and limited emergency medicine-specific literature exists.

OBJECTIVE

This narrative review evaluates the role of sugammadex for the reversal of neuromuscular blockade in the ED.

DISCUSSION

The basic pharmacology, duration of action, adverse effects, and important medication and disease interactions specific to sugammadex are well described. Case reports suggest sugammadex can reverse neuromuscular blockade to facilitate an urgent, neurologic examination by an emergency physician or consultant. Multiple case reports of failure to improve airway patency with the use of sugammadex, even when neuromuscular blockade is completely reversed, and concern for added difficulty of definitive airway management in a patient with spontaneous movement suggest that sugammadex should largely be omitted from failed or difficult airway management strategies. Instead, it is important to focus on the ability to oxygenate and ventilate, including progression to surgical airway or jet ventilation if needed.

CONCLUSION

Sugammadex is an effective, rapid reversal agent for rocuronium and has the potential use to facilitate an urgent neurologic examination shortly after administration of rocuronium. Its routine inclusion in a failed or difficult emergency airway is not supported by available literature.

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.

Risk factors for and prediction of post-intubation hypotension in critically ill adults: A multicenter prospective cohort study

Objective

Hypotension following endotracheal intubation in the ICU is associated with poor outcomes. There is no formal prediction tool to help estimate the onset of this hemodynamic compromise. Our objective was to derive and validate a prediction model for immediate hypotension following endotracheal intubation.

Methods

A multicenter, prospective, cohort study enrolling 934 adults who underwent endotracheal intubation across 16 medical/surgical ICUs in the United States from July 2015-January 2017 was conducted to derive and validate a prediction model for immediate hypotension following endotracheal intubation. We defined hypotension as: 1) mean arterial pressure <65 mmHg; 2) systolic blood pressure <80 mmHg and/or decrease in systolic blood pressure of 40% from baseline; 3) or the initiation or increase in any vasopressor in the 30 minutes following endotracheal intubation.

Results

Post-intubation hypotension developed in 344 (36.8%) patients. In the full cohort, 11 variables were independently associated with hypotension: increasing illness severity; increasing age; sepsis diagnosis; endotracheal intubation in the setting of cardiac arrest, mean arterial pressure <65 mmHg, and acute respiratory failure; diuretic use 24 hours preceding endotracheal intubation; decreasing systolic blood pressure from 130 mmHg; catecholamine and phenylephrine use immediately prior to endotracheal intubation; and use of etomidate during endotracheal intubation. A model excluding unstable patients’ pre-intubation (those receiving catecholamine vasopressors and/or who were intubated in the setting of cardiac arrest) was also developed and included the above variables with the exception of sepsis and etomidate. In the full cohort, the 11 variable model had a C-statistic of 0.75 (95% CI 0.72, 0.78). In the stable cohort, the 7 variable model C-statistic was 0.71 (95% CI 0.67, 0.75). In both cohorts, a clinical risk score was developed stratifying patients’ risk of hypotension.

Conclusions

A novel multivariable risk score predicted post-intubation hypotension with accuracy in both unstable and stable critically ill patients.

Study registration

Clinicaltrials.gov identifier: NCT02508948 and Registered Report Identifier: RR2-10.2196/11101.

Prehospital Efficacy and Adverse Events Associated with Bolus Dose Epinephrine in Hypotensive Patients During Ground-Based EMS Transport

BACKGROUND

The utility and efficacy of bolus dose vasopressors in hemodynamically unstable patients is well-established in the fields of general anesthesia and obstetrics. However, in the prehospital setting, minimal evidence for bolus dose vasopressor use exists and is primarily limited to critical care transport use. Hypotensive episodes, whether traumatic, peri-intubation-related, or septic, increase patient mortality. The purpose of this study is to assess the efficacy and adverse events associated with prehospital bolus dose epinephrine use in non-cardiac arrest, hypotensive patients treated by a single, high-volume, ground-based Emergency Medical Services (EMS) agency.

METHODS

This is a retrospective, observational study of all non-cardiac arrest EMS patients treated for hypotension using bolus dose epinephrine from September 12, 2018 through September 12, 2019. Inclusion criteria for treatment with bolus dose epinephrine required a systolic blood pressure (SBP) measurement <90mmHg. A dose of 20mcg every two minutes, as needed, was allowed per protocol. The primary data source was the EMS electronic medical record.

RESULTS

Forty-two patients were treated under the protocol with a median (IQR) initial SBP immediately prior to treatment of 78mmHg (65-86) and a median (IQR) initial mean arterial pressure (MAP) of 58mmHg (50-66). The post-bolus SBP and MAP increased to 93mmHg (75-111) and 69mmHg (59-83), respectively. The two most common patient presentations requiring protocol use were altered mental status (55%) and respiratory failure (31%). Over one-half of the patients treated required both advanced airway management (62%) and multiple bolus doses of vasopressor support (55%). A single episode of transient severe hypertension (SBP>180mmHg) occurred, but there were no episodes of unstable tachyarrhythmia or cardiac arrest while en route or upon arrival to the receiving hospitals.

CONCLUSION

These preliminary data suggest that the administration of bolus dose epinephrine may be effective at rapidly augmenting hypotension in the prehospital setting with a minimal incidence of adverse events. Paramedic use of bolus dose epinephrine successfully increased SBP and MAP without clinically significant side effects. Prospective studies with larger sample sizes are needed to further investigate the effects of prehospital bolus dose epinephrine on patient morbidity and mortality.

Systematic Application of Rapid Sequence Intubation With Remifentanil During COVID-19 Pandemic

In this letter, the authors wonder about the need to apply some of the precautions that have been repeatedly suggested during the recent COVID-19 (coronavirus disease 19) pandemic not only to suspected or documented cases of infection but also to all the new cases entering the hospital. In this regard, orotracheal intubation has been universally recognized as a maneuver with a high risk of viral transmission. On the other hand, rapid sequence induction, which represents the gold standard for limiting the risk of transmission for health care professionals, implies side effects that can be potentially harmful for patients with impaired hemodynamics. In this regard, the authors report a particular type of rapid induction that they are performing in a systematic way during the recent pandemic in cardiac surgery patients. This is performed after the patient reaches a deep analgesic plan, thanks to the unique characteristics of the opioid remifentanil. This type of induction, already tested in vasculopathic patients who underwent carotid surgery, is characterized by great hemodynamic stability and is very advantageous, in the writer's experience, when rapid sequence induction has to be systematically applied to cardiovascular patients, especially if you only want to protect operators.

High-Risk Airway Management in the Emergency Department. Part I: Diseases and Approaches

BACKGROUND

Successful airway management is critical to the practice of emergency medicine. Emergency physicians must be ready to optimize and prepare for airway management in critically ill patients with a wide range of physiologic challenges. Challenges in airway management commonly encountered in the emergency department are discussed using a pearl and pitfall discussion in this first part of a 2-part series.

OBJECTIVE

This narrative review presents an evidence-based approach to airway and patient management during endotracheal intubation in challenging cases that are commonly encountered in the emergency department.

DISCUSSION

Adverse events during emergent airway management are common, with postintubation cardiac arrest reported in as many as 1 in 25 intubations. Many of these adverse events can be avoided with the proper identification and understanding of the underlying physiology, preparation, and postintubation management. Patients with high-risk features including severe metabolic acidosis; shock and hypotension; obstructive lung disease; pulmonary hypertension, right ventricle failure, and pulmonary embolism; and severe hypoxemia must be managed with airway expertise.

CONCLUSIONS

This narrative review discusses the pearls and pitfalls of commonly encountered physiologic high-risk intubations with a focus on the emergency clinician.

High-Risk Airway Management in the Emergency Department: Diseases and Approaches, Part II

BACKGROUND

Successful airway management is critical to the practice of emergency medicine. Thus, emergency physicians must be ready to optimize and prepare for airway management in critically ill patients with a wide range of physiologic challenges. Challenges in airway management commonly encountered in the emergency department are discussed using a pearl and pitfall discussion in this second part of a 2-part series.

OBJECTIVE

This narrative review presents an evidence-based approach to airway and patient management during endotracheal intubation in challenging cases commonly encountered in the emergency department.

DISCUSSION

Adverse events during emergent airway management are common with postintubation cardiac arrest, reported in as many as 1 in 25 intubations. Many of these adverse events can be avoided by proper identification and understanding the underlying physiology, preparation, and postintubation management. Those with high-risk features including trauma, elevated intracranial pressure, upper gastrointestinal bleed, cardiac tamponade, aortic stenosis, morbid obesity, and pregnancy must be managed with airway expertise.

CONCLUSIONS

This narrative review discusses the pearls and pitfalls of commonly encountered physiologic high-risk intubations with a focus on the emergency clinician.

Effect of Ketamine/Propofol Admixture on Peri-Induction Hemodynamics: A Systematic Review and Meta-Analysis

To evaluate the effectiveness of an admixture of ketamine and propofol on peri-induction hemodynamics during airway manipulation, we searched electronic databases of randomized controlled trials from January 1, 2000, to October 17, 2018. Trial screening, selection, and data extraction were done independently by two reviewers with outcomes pooled across included trials using the random-effects model. We included 10 randomized trials (722 patients, mean age of 53.99 years, 39.96% female). American Society of Anesthesiologists physical status was reported in 9 trials with classes I and II representing the majority. Ketamine/propofol admixture was associated with a nonsignificant increase in heart rate (weighted mean difference, 3.36 beats per minute (95% CI, -0.88, 7.60), I 2 = 88.6%), a statistically significant increase in systolic blood pressure (weighted mean difference, 9.67 mmHg (95% CI, 1.48, 17.86), I 2 = 87.2%), a nonsignificant increase in diastolic blood pressure (weighted mean difference, 2.18 mmHg (95% CI, -2.82, 7.19), I 2 = 73.1%), and a nonsignificant increase in mean arterial pressure (weighted mean difference, 3.28 mmHg (95% CI, -0.94, 7.49), I 2 = 69.9%) compared to other agents. The risk of bias was high and the certainty of evidence was low. In conclusion, among patients undergoing airway manipulation and needing sedation, the use of a ketamine/propofol admixture may be associated with better hemodynamics compared to nonketamine/propofol sedation. This trial is registered with CRD42019125725.

The Use of Ketamine for Air Medical Rapid Sequence Intubation Was Not Associated With a Decrease in Hypotension or Cardiopulmonary Arrest

OBJECTIVE

Rapid sequence intubation (RSI) is associated with a number of complications that can increase morbidity and mortality. Among RSI agents used to blunt awareness of the procedure and produce amnesia, ketamine is unique in its classification as a dissociative agent rather than a central nervous system depressant. Thus, ketamine should have a lower risk of peri-RSI hypotension because of the minimal sympatholysis compared with other agents. Recent recommendations include the use of ketamine for RSI in hemodynamically unstable patients. The main goal of this analysis was to explore the incidence of hypotension and/or cardiopulmonary arrest in patients receiving ketamine, etomidate, midazolam, and fentanyl during air medical RSI. We hypothesized that ketamine would be associated with a lower risk of hemodynamic complications, particularly after adjusting for covariables reflecting patient acuity. In addition, we anticipated that an increased prevalence of ketamine use would be associated with a decreased incidence of peri-RSI hypotension and/or arrest.

METHODS

This was a retrospective, observational study using a large air medical airway database. A waiver of informed consent was granted by our institutional review board. Descriptive statistics were used to present demographic and clinical data. The incidence rates of hypotension and cardiopulmonary arrest were calculated for each sedative/dissociative agent. Multivariable logistic regression was used to calculate the odds ratios of both hypotension and arrest for each of the sedative/dissociative agents. The prevalence of use for each agent and the incidence of hemodynamic complications (hypotension and arrest) were determined over time.

RESULTS

A total of 7,466 RSI patients were included in this analysis. The use of ketamine increased over the duration of the study. Ketamine was associated with a higher incidence of both hypotension and arrest compared with other agents, even after adjustment for multiple covariables. The overall incidence of hypotension, desaturation, and cardiopulmonary arrest did not change over the study period.

CONCLUSIONS

Although the incidence of hemodynamic complications was higher in patients receiving ketamine, this may reflect a selection bias toward more hemodynamically unstable patients in the ketamine cohort. The incidence of hypotension and arrest did not change over time despite an increase in the prevalence of ketamine use for air medical RSI. These data do not support a safer hemodynamic profile for ketamine.