Postintubation hypotension in intensive care unit patients: A multicenter cohort study

Postintubation hypotension following rapid sequence intubation with full- vs reduced-dose induction agent

PURPOSE

Rapid sequence intubation (RSI) is a common emergency department (ED) procedure with an associated complication of postintubation hypotension (PIH). It has not been clearly established whether the selection and dose of induction agent affect risk of PIH. The objective of this study was to determine the incidence of PIH in patients receiving full-dose compared to reduced-dose induction agent for RSI in the ED.

METHODS

This was a health system-wide, retrospective cohort study comparing incidence of PIH based on the induction medication and dose given for RSI in the ED. Patients were included if they underwent RSI from July 1, 2018, through December 31, 2020, were 18 years of age or older, and received etomidate or ketamine. A reduced dose was defined as a ketamine dose of 1.25 mg/kg or less and an etomidate dose of 0.2 mg/kg or less.

RESULTS

A total of 909 patients were included in the final analysis, with most receiving etomidate (n = 764; 84%) and a smaller number receiving ketamine (n = 145; 16%). Patients who received ketamine had a higher mean pre-intubation shock index (full dose, 1.08; reduced dose, 1.04) than those who received etomidate (full dose, 0.89; reduced dose, 0.92) (P ≤ 0.001). Reduced doses of induction agent were observed for 107 patients receiving etomidate (14.0%) and 60 patients receiving ketamine (41.4%). Patients who received full-dose ketamine for induction had the highest rate of PIH (n = 31; 36.5%), and the difference was statistically significant compared to patients receiving reduced-dose ketamine (16.7%; P = 0.021) and full-dose etomidate (22.8%; P = 0.010).

CONCLUSION

We observed that full-dose ketamine was associated with the highest rate of PIH; however, this group had the poorest baseline hemodynamics, confounding interpretation. Our results do not support broad use of a reduced-dose induction agent.

The Importance of Circulation in Airway Management: Preventing Postintubation Hypotension in the Trauma Bay

OBJECTIVE

To identify the modifiable and nonmodifiable risk factors associated with postintubation hypotension (PIH) among trauma patients who required endotracheal intubation (ETI) in the trauma bay.

BACKGROUND

ETI has been associated with hemodynamic instability, termed PIH, yet its risk factors in trauma patients remain underinvestigated.

METHODS

This is a prospective observational study at a level I trauma center over 4 years (2019-2022). All adult (≥18) trauma patients requiring ETI in the trauma bay were included. Blood pressure was monitored both preintubation and postintubation. Multivariable logistic regression analysis was performed to identify the modifiable and nonmodifiable factors associated with PIH.

RESULTS

Seven hundred eight patients required ETI in the trauma bay, of which, 435 (61.4%) developed PIH. The mean (SD) age was 43 (21) years and 71% were male. Median [interquartile range] arrival Glasgow Coma Scale was 7 [3-13]. Patients who developed PIH had a lower mean (SD) preintubation systolic blood pressure [118 (46) vs 138 (28), P <0.001] and higher median [interquartile range] Injury Severity Score: 27 [21-38] versus 21 [9-26], P <0.001. Multivariable regression analysis identified body mass index >25, increasing Injury Severity Score, penetrating injury, spinal cord injury, preintubation packed red blood cell requirements, and diabetes mellitus as nonmodifiable risk factors associated with increased odds of PIH. In contrast, preintubation administration of 3% hypertonic saline and vasopressors were identified as the modifiable factors significantly associated with reduced PIH.

CONCLUSIONS

More than half of the patients requiring ETI in the trauma bay developed PIH. This study identified modifiable and nonmodifiable risk factors that influence the development of PIH, which will help physicians when considering ETI upon patient arrival.

LEVEL OF EVIDENCE

Level III-Prognostic study.

Intubation of critically ill patients: A pilot study of minute-by-minute physiological changes within an Australian tertiary intensive care unit

BACKGROUND

There are no published minute-by-minute physiological assessment data for endotracheal intubation (ETT) performed in the intensive care unit (ICU). The majority of physiological data is available from Europe and North America where etomidate is the induction agent administered most commonly.

AIMS

The aim of this study was to describe the feasibility of obtaining minute-by-minute physiological and medication data surrounding ETT in an Australian tertiary ICU and to assess its associated outcomes.

METHODS

We performed a single-centre feasibility observational study. We obtained minute-by-minute data on physiological variables and medications for 15 min before and 30 min after ETT. We assessed feasibility as enrolled to screened patient ratio and completeness of data collection in enrolled patients. Severe hypotension (systolic blood pressure < 65 mmHg) and severe hypoxaemia (pulse oximetry saturation < 80%) were the secondary clinical outcomes.

RESULTS

We screened 43 patients and studied 30 patients. The median age was 58.5 (interquartile range: 49-70) years, and 18 (60%) were male. Near-complete (97%) physiological and medication data were obtained in all patients at all times. Overall, 15 (50%) ETTs occurred after hours (17:30-08:00) and 90% were by video laryngoscopy with a 90% first-pass success rate. Prophylactic vasopressors were used in 50% of ETTs. Fentanyl was used in all except one ETT at a median dose of 2.5 mcg/kg. Propofol (63%) or midazolam (50%) were used as adjuncts at low dose. Rocuronium was used in all but one patient. There were no episodes of severe hypotension and only one episode of short-lived severe hypoxaemia.

CONCLUSION

Minute-by-minute recording of ETT-associated physiological changes in the ICU was feasible but only fully available in two-thirds of the screened patients. ETT was based on fentanyl induction, low-dose adjunctive sedation, and frequent prophylactic vasopressor therapy and was associated with no severe hypotension and a single short-lived episode of severe hypoxaemia.

Comparison of efficacy and safety of etomidate with other anesthesia induction drugs for patients undergoing cardiac surgery: A systematic review and meta-analysis of randomized controlled trials

Introduction

Etomidate is commonly used to induce anesthesia in cardiac surgery patients due to its favorable cardiovascular profile. Sedative-hypnotic effects are mediated by gammaaminobutyric acid (GABA) receptor complexes in the central nervous system. There are numerous studies in which etomidate and other drugs are compared in terms of their clinical outcomes. The relative efficacy and safety of etomidate, however, remains inconclusive. In this study, we performed a systematic analysis of randomized controlled trials to assess the impact of etomidate, on patients undergoing cardiac surgery, with respect to patient outcome and adverse events.

Methods

A systematic review was conducted of all existing clinical trials exploring the safety and efficacy of etomidate in patients undergoing cardiac surgery. Randomized controlled trials (RCTs) that compared etomidate with other drugs during induction in adult cardiac surgery assessing hemodynamic parameters and clinical outcomes were included, while studies involving non-cardiac or pediatric surgery and those lacking relevant outcome data were excluded. Primary outcomes were all-cause 30-day mortality. Secondary outcomes included duration of tracheal intubation, duration of intensive care unit (ICU) stay, duration of hospital stay, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR) and other hemodynamic parameters, vasopressor requirements after induction and intubation, cortisol levels, and incidence of myoclonus.

Results

Sixteen randomized controlled trials involving 1162 patients were included. Etomidate did not affect the all-cause 30-day mortality of patients undergoing cardiac surgery compared to comparator drugs (RR, 0.96; 95 % CI, 0.26 to 3.49; P = 0.95). There were no significant differences in the duration of tracheal intubation (MD, -0.08 h; 95 % CI, -1.96 to 1.81; P = 0.94), the duration of ICU stay (MD, -2.07 h; 95 % CI, -8.09 to 3.96; P = 0.50) or the duration of hospital stay (MD, -0.62 d; 95 % CI, -2.25 to 1.00; P = 0.45) when etomidate was compared to comparator drugs. Patients receiving etomidate demonstrated a more stable hemodynamic profile after induction and intubation compared to those receiving comparator drugs. The requirement of a vasopressor after induction and intubation was significantly reduced with etomidate compared with those with comparator drugs (RR, 0.37; 95 % CI, 0.25 to 0.56; P < 0.00001).

Conclusions

This systematic meta-analysis found a significant heterogeneity among included studies. In addition, most studies focused only on the hemodynamic profile of etomidate. Thus, efficacy and safety of etomidate could not be answered within this context. Nevertheless, for patients undergoing cardiac surgery, etomidate seems to offer a minimal beneficial cardiovascular profile in comparison with other agents during induction and intubation. However, improved hemodynamics did not improve clinical outcomes as Etomidate did not affect mortality, duration of tracheal intubation, the length of stay in ICU and hospital. Finally, infectious side effects as one important trigger for increased mortality in ICU patients due to the use of Etomidate could not be analyzed as data were mostly missing.

The use of vasopressors to reduce post-intubation hypotension in critically ill adult patients undergoing emergent endotracheal intubation: a scoping review

INTRODUCTION

Patients requiring emergent endotracheal intubation are at higher risk of post-intubation hypotension due to altered physiology in critical illness. Post-intubation hypotension increases mortality and hospital length of stay, however, the impact of vasopressors on its incidence and outcomes is not known. This scoping review identified studies reporting hemodynamic data in patients undergoing emergent intubation to provide a literature overview on post-intubation hypotension in cohorts that did and did not receive vasopressors.

METHODS

A systematic search of CINAHL, Cochrane, EMBASE and PubMed-Medline was performed from database inception until September 28, 2023. Two independent reviewers completed the title and abstract screen, full text review and data extraction per PRISMA guidelines. Studies including patients < 18 years or intubations during cardiac arrest were excluded. Primary outcome was the presence of hypotension within 30 min of emergent intubation. Secondary outcomes included mortality at 1 h and in-hospital.

RESULTS

The systematic search yielded 13,126 articles, with 61 selected for final inclusion. There were 24,547 patients with a mean age of 57.2 years and a slight male predominance (63.8%). Respiratory failure was the most common intubation indication. Across 18 studies reporting on vasopressor use prior to intubation, 1171/7085 patients received vasopressors pre-intubation. Post-intubation hypotension occurred in 22.2% of patients across all studies, and in 34.3% of patients in studies where vasopressor administration pre-intubation was specifically reported. One-hour mortality of patients across all studies and within the vasopressor use studies was 1.2% and 1.6%, respectively. In-hospital mortality across studies was 21.5%, and 13.1% in studies which reported on vasopressor use pre-intubation.

CONCLUSION

Patients requiring emergent intubation have a high rate of post-intubation hypotension and in-hospital mortality. While there is an intuitive rationale for the use of vasopressors during emergent intubation, current evidence is limited to support a definitive change in clinical practice at this time.

Population Pharmacokinetic Modelling of Norepinephrine in Healthy Volunteers Prior to and During General Anesthesia

BACKGROUND

Intraoperation hypotension (IOH) is commonly observed in patients undergoing surgery under general anesthesia, and even a brief episode of IOH can lead to unfavorable outcomes. To reduce the risk, blood pressure is closely measured during general anesthesia, and norepinephrine (NE) is frequently administered if hypotension is detected. Despite its routine application, information on the dose-exposure-response relationship of NE remains limited. Additionally, quantification of the influence of general anesthesia on the pharmacokinetics (PK) of NE is lacking.

OBJECTIVE

In this study, we aimed to describe NE PK in healthy volunteers and the influence of general anesthesia on its PK.

METHODS

A single-center, cross-over study was conducted in healthy volunteers. The volunteers received a step-up NE dosing scheme (0.04, 0.08, 0.12, 0.16 and 0.20 mcg-1/kg-1/min-1) first in the awake state and then under general anesthesia. General anesthesia was administered using a propofol/remifentanil Eleveld target-controlled infusion. During general anesthesia, a 30-second electrical stimulus was given as surrogate for surgical incision to the volunteers at each dosage step. Blood samples were drawn before the initial dosing and after each dosing step, and plasma NE, propofol and remifentanil concentrations were subsequently determined. A population PK model was developed using non-linear mixed effects modelling. Simulations were conducted to predict the plasma NE concentration in patients at different measured propofol concentrations.

RESULTS

A total of 1219 samples were analyzed from 36 volunteers. A two-compartment model with a first-order elimination best described the data. Weight, age, and session effect (awake vs general anesthesia) were identified as relevant covariates on the clearance (CL) of NE. A 10% decrease in NE CL was observed after general anesthesia induction. This difference between sessions is better explained by the measured concentration of propofol, rather than the anticipated impact of cardiac output. The estimated post-stimulation NE concentration is 0.66 nmol/L-1 (95% CI 0.06-1.20 nmol/L-1) lower than the pre-stimulation NE concentration. Model simulation indicates that patients at a higher measured propofol concentration (e.g., 6 mcg/mL-1) exhibited higher NE concentrations (95% PI 18.10-43.89 nmol/L-1) than patients at a lower measured propofol concentration (e.g., 3 mcg/mL-1) (95% PI 16.81-38.91 nmol L-1).

CONCLUSION

The NE PK is well described with a two-compartment model with a first-order elimination. NE CL exhibiting a 10% decrease under general anesthesia, with this difference being attributed to the measured concentration of propofol. The impact of stimulation on NE PK under general anesthesia is very limited.

CLINICAL TRIALS REGISTRATION NUMBER

NL9312.

Alfentanil versus fentanyl for emergency department rapid sequence induction with ketamine: A-FAKT, a pilot randomized trial

BACKGROUND

Fentanyl is often administered during rapid sequence induction of anesthesia (RSI) in the emergency department (ED) to ameliorate the hypertensive response that may occur. Due to its more rapid onset, the use of alfentanil may be more consistent with both the onset time of the sedative and the commencement of laryngoscopy. As such, we compared the effect of alfentanil and fentanyl on post-induction hemodynamic changes when administered as part of a standardized induction regimen including ketamine and rocuronium in ED RSI.

METHODS

This was a double-blind pilot randomized controlled trial of adult patients requiring RSI in the ED of three urban Australian hospitals. Patients were randomized to receive either alfentanil or fentanyl in addition to ketamine and rocuronium for RSI. Non-invasive blood pressure and heart rate were measured immediately before and at two, four, and six minutes after induction. The primary outcome was the occurrence of at least one post-induction systolic blood pressure outside the pre-specified range of 100-160mmHg (with adjustment for patients with baseline hypertension). Secondary outcomes included hypertension, hypotension, hypoxia, first-pass intubation success, 30-day mortality, and the pattern of hemodynamic changes.

RESULTS

A total of 61 patients were included in the final analysis (31 in the alfentanil group and 30 in the fentanyl group). The primary outcome was met in 58% of the alfentanil group and 50% of the fentanyl group (difference 8%, 95% confidence interval: -17% to 33%). The 30-day mortality rate, first-pass success rate, and incidences of hypertension, hypotension, and hypoxia were similar between the groups. There were no significant differences in systolic blood pressure or heart rate between the groups at any of the measured time-points.

CONCLUSION

Alfentanil and fentanyl produced comparable post-induction hemodynamic changes when used as adjuncts to ketamine in ED RSI. Future studies could consider comparing different dosages of these opioids.

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.

Dexmedetomidine Inhibits Hippocampal Neuronal Damage Caused by Persistent Isoflurane-Induced Hypotension in Rat Model of Chronic Cerebral Hypoperfusion

Purpose The purpose of this study was to investigate the effect of dexmedetomidine (DEX) on hypotension-induced neuronal damage in a chronic cerebral hypoperfusion (CCH) model of rats, an established model of cerebral white matter lesions (WML) in humans, which is prevalent in the elderly and closely related to cognitive decline. Methods The CCH model rats were randomly assigned to one of four groups: normotension + no DEX (NN) group (n = 6), normotension + DEX (ND) group (n = 6), hypotension + no DEX (HN) group (n = 6), or hypotension + DEX (HD) group (n = 6). Under isoflurane anesthesia, mean arterial blood pressure was maintained at or above 80 mmHg (normotension) or below 60 mmHg (hypotension) for a duration of two hours. The DEX groups received 50 μg of DEX intraperitoneally. Two weeks later, the Y-maze test and, after preparing brain slices, immunohistochemical staining were performed using antibodies against neuronal nuclei (NeuN), microtubule-associated protein 2 (MAP2), glial fibrillary acidic protein (GFAP), and Ionized calcium-binding adapter molecule 1 (Iba1). Results Behavioral observations showed no significant differences among the groups. Significant reductions of both NeuN-positive cells and the MAP2-positive area were found in the hippocampal CA1 in the HN group compared with NN and ND groups, but not in the HD group. GFAP and Iba-1-positive areas were significantly increased in the HN group, but not in the HD group. Conclusion DEX significantly ameliorated hypotension-induced neuronal damage and both astroglial and microglial activation in the CA1 region of CCH rats.

Validation of Difficult Airway Physiological Score (DAPS) in Critically Ill Adults Undergoing Endotracheal Intubation in the Emergency Department

Background

Critically ill patients have increased risk of cardiovascular collapse following endotracheal intubation due to physiological instability. This study aims to validate the Difficult Airway Physiological Score (DAPS) in adults to predict the risk of serious outcomes in the emergency department of a tertiary care private hospital.

Methods

This is a cohort study conducted in the emergency department (ED) from 2021 to 2022. Difficult Airway Physiological Score (DAPS) was derived from a sample of 1021 patients through a retrospective study. The variables in the score were age, gender, time of intubation, vitals and vomiting at presentation, pH <7.3, fever, physician's anticipation for patient decline, and agitation. The model performance was assessed prospectively on a separate dataset (n = 326) using train-test split method. Postintubation desaturation, hypotension, cardiac arrest, and mortality postintubation were the serious outcomes. ROC analysis, sensitivity, specificity, PPV, and NPV were used to assess score validity.

Results

Our study includes 326 patients, of which 123 (37.7%) were males and 203 (62.2%) were females. The sample was divided into high-risk (DAPS ≥10) group, n = 194 with mean age of 52 (SD = ±18) years, and low-risk (DAPS <10) group, n = 132 with mean age of 47.7 (SD = ±17.4) years. The shock index ≥0.9 was in 128 (66%), while it was <0.9 in low-risk n = 111 (84%), p value <0.001. Similarly, pH <7.3 was seen in 70 (36.1%) in high-risk group compared to 4 (3%) in low-risk group, p value <0.001. Cardiac arrest was observed in 56 (17.2%) patients, of which 45 (23.2%) were in high-risk and 11 (8.3%) in low-risk groups (p < 0.001). Hypotension was the primary outcome in the high-risk group 100 (51.5%) versus 32 (24.2%) in low-risk group (p < 0.001). The DAPS of 10 had an area under the curve of 0.865 (0.71-0.84). The sensitivity of DAPS was 78.5%, specificity 77.9%, and accuracy 78.2%.

Conclusion

The score can accurately predict serious outcomes in critically ill adult patients with physiologically difficult airway demonstrating good sensitivity and specificity.

Hypotension during intensive care stay and mortality and morbidity: a systematic review and meta-analysis

PURPOSE

The aim of this study is to provide a summary of the existing literature on the association between hypotension during intensive care unit (ICU) stay and mortality and morbidity, and to assess whether there is an exposure-severity relationship between hypotension exposure and patient outcomes.

METHODS

CENTRAL, Embase, and PubMed were searched up to October 2022 for articles that reported an association between hypotension during ICU stay and at least one of the 11 predefined outcomes. Two independent reviewers extracted the data and assessed the risk of bias. Results were gathered in a summary table and studies designed to investigate the hypotension-outcome relationship were included in the meta-analyses.

RESULTS

A total of 122 studies (176,329 patients) were included, with the number of studies varying per outcome between 0 and 82. The majority of articles reported associations in favor of 'no hypotension' for the outcomes mortality and acute kidney injury (AKI), and the strength of the association was related to the severity of hypotension in the majority of studies. Using meta-analysis, a significant association was found between hypotension and mortality (odds ratio: 1.45; 95% confidence interval (CI) 1.12-1.88; based on 13 studies and 34,829 patients), but not for AKI.

CONCLUSION

Exposure to hypotension during ICU stay was associated with increased mortality and AKI in the majority of included studies, and associations for both outcomes increased with increasing hypotension severity. The meta-analysis reinforced the descriptive findings regarding mortality but did not yield similar support for AKI.

Spanish Society of Anesthesiology, Reanimation and Pain Therapy (SEDAR), Spanish Society of Emergency and Emergency Medicine (SEMES) and Spanish Society of Otolaryngology, Head and Neck Surgery (SEORL-CCC) Guideline for difficult airway management. Part I

The Airway Management section of the Spanish Society of Anesthesiology, Resuscitation, and Pain Therapy (SEDAR), the Spanish Society of Emergency Medicine (SEMES), and the Spanish Society of Otorhinolaryngology and Head and Neck Surgery (SEORL-CCC) present the Guide for the comprehensive management of difficult airway in adult patients. Its principles are focused on the human factors, cognitive processes for decision-making in critical situations, and optimization in the progression of strategies application to preserve adequate alveolar oxygenation in order to enhance safety and the quality of care. The document provides evidence-based recommendations, theoretical-educational tools, and implementation tools, mainly cognitive aids, applicable to airway management in the fields of anesthesiology, critical care, emergencies, and prehospital medicine. For this purpose, an extensive literature search was conducted following PRISMA-R guidelines and was analyzed using the GRADE methodology. Recommendations were formulated according to the GRADE methodology. Recommendations for sections with low-quality evidence were based on expert opinion through consensus reached via a Delphi questionnaire.

Noninvasive Cardiac Output Monitoring (NICOM) in the Critically Ill Patient Undergoing Endotracheal Intubation: A Prospective Observational Study

Background: Cardiovascular instability occurring during endotracheal intubation (ETI) in the critically ill is a commonly recognized phenomenon. However, this complication has not been evaluated in terms of the physiological cause (ie, decreased preload, contractility, or afterload) leading to the instability. Thus, the aim of the current investigation was to describe the hemodynamics occurring during ETI with noninvasive physiologic monitoring and to collect preliminary data on the hemodynamic effects of induction agents and positive pressure ventilation. Methods: A multicenter prospective study enrolling adult (≥18 years) critically ill patients undergoing ETI with noninvasive cardiac output monitoring in a medical/surgical intensive care unit from June 2018 to May 2019 was conducted. This study used the Cheetah Medical noninvasive cardiac output monitor to collect hemodynamic data during the peri-intubation period. Additional data collected included baseline characteristics such as illness severity, peri-intubation pharmacologic administration, and mechanical ventilation settings. Results: From the original 27 patients, only 19 (70%) patients had complete data and were included in the final analysis. Propofol was the most common sedative 8 (42%) followed by ketamine 6 (32%) and etomidate 5 (26%). Patients given propofol demonstrated a decrease in total peripheral resistance index (delta change [dynes × s/cm-5/m2]: -2.7 ± 778.2) but stabilization in cardiac index (delta change (L/min/m2]: 0.1 ± 1.5) while etomidate and ketamine demonstrated increases in total peripheral resistance index (etomidate delta change [dynes × s/cm-5/m2]: 302.1 ± 414.3; ketamine delta change [dynes × s/cm-5/m2]: 278.7 ± 418.9) but only etomidate resulted in a decrease in cardiac index (delta change [L/min/m2]: -0.3 ± 0.5). Positive pressure ventilation resulted in minimal changes to hemodynamics during ETI. Conclusions: The current study demonstrates that although propofol administration leads to a decrease in total peripheral resistance index, cardiac index is maintained while etomidate leads to a decrease in cardiac index with both etomidate and ketamine increasing total peripheral resistance index. These hemodynamic profiles are minimally affected by positive pressure ventilation. Study registration: ClinicalTrials.gov ID, NCT03525743.

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.

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.

Emergency airway management in a tertiary trauma centre (AIRMAN): a one-year prospective longitudinal study

PURPOSE

Emergency airway management can be associated with a range of complications including long-term neurologic injury and death. We studied the first-pass success rate with emergency airway management in a tertiary care trauma centre. Secondary outcomes were to identify factors associated with first-pass success and factors associated with adverse events peri-intubation.

METHODS

We performed a single-centre, prospective, observational study of patients ≥ 17 yr old who were intubated in the emergency department (ED), surgical intensive care unit (SICU), medical intensive care unit (MICU), and inpatient wards at our institution. Ethics approval was obtained from the local research ethics board.

RESULTS

In a seven-month period, there were 416 emergency intubations and a first-pass success rate of 73.1%. The first-pass success rates were 57.5% on the ward, 66.1% in the intensive care units (ICUs) and 84.3% in the ED. Equipment also varied by location; videolaryngoscopy use was 65.1% in the ED and only 10.6% on wards. A multivariate regression model using the least absolute shrinkage and selection algorithm (LASSO) showed that the odds ratios for factors associated with two or more intubation attempts were location (wards, 1.23; MICU, 1.24; SICU, 1.19; reference group, ED), physiologic instability (1.19), an anatomically difficult airway (1.05), hypoxemia (1.98), lack of neuromuscular blocker use (2.28), and intubator inexperience (1.41).

CONCLUSIONS

First-pass success rates varied widely between locations within the hospital and were less than those published from similar institutions, except for the ED. We are revamping ICU protocols to improve the first-pass success rate.

A prospective observational study comparing outcomes before and after the introduction of an intubation protocol during the COVID-19 pandemic

OBJECTIVE

Orotracheal intubation is a life-saving procedure commonly performed in the Intensive Care unit and Emergency Department as a part of emergency airway management. Prior to the COVID-19 pandemic, our center undertook a prospective observational study to characterize emergency intubation performed in the emergency department and critical care settings at Manitoba's largest tertiary hospital. During this study, a natural experiment emerged when a standardized "COVID-Protected Rapid Sequence Intubation Protocol" was implemented in response to the pandemic. The resultant study aimed to answer the question; in adult ED patients undergoing emergent intubation by EM and CCM teams, does the use of a "COVID-Protected Rapid Sequence Intubation Protocol" impact first-pass success or other intubation-related outcomes?

METHODS

A single-center prospective quasi-experimental before and after study was conducted. Data were prospectively collected on consecutive emergent intubations. The primary outcome was the difference in first-pass success rates. Secondary outcomes included best Modified Cormack-Lehane view, hypoxemia, hypotension, esophageal intubation, cannot intubate cannot oxygenate scenarios, CPR post intubation, vasopressors required post intubation, Intensive Care Unit (ICU) mortality, ICU length of stay (LOS), and mechanical ventilation days.

RESULTS

Data were collected on 630 patients, 416 in the pre-protocol period and 214 in the post-protocol period. First-pass success rates in the pre-protocol period were found to be 73.1% (n = 304). Following the introduction of the protocol, first-pass success rates increased to 82.2% (n = 176, p = 0.0105). There was a statistically significant difference in Modified Cormack-Lehane view favoring the protocol (p = 0.0191). Esophageal intubation rates were found to be 5.1% pre-protocol introduction versus 0.5% following the introduction of the protocol (p = 0.0172).

CONCLUSION

A "COVID-Protected Protocol" implemented by Emergency Medicine and Critical Care teams in response to the COVID-19 pandemic was associated with increased first-pass success rates and decreases in adverse events.

Hypotension Prediction Score for Endotracheal Intubation in Critically Ill Patients: A Post Hoc Analysis of the HEMAIR Study

BACKGROUND

Hypotension with endotracheal intubation (ETI) is common and associated with adverse outcomes. We sought to evaluate whether a previously described hypotension prediction score (HYPS) for ETI is associated with worse patient outcomes and/or clinical conditions.

METHODS

This study is a post hoc analysis of a prospective observational multicenter study involving adult (age ≥18 years) intensive care unit (ICU) patients undergoing ETI in which the HYPS was derived and validated on the entire cohort and a stable subset (ie, patients in stable condition). We evaluated the association between increasing HYPSs in both subsets and several patient-centered outcomes and clinical conditions.

RESULTS

Complete data for HYPS calculations were available for 783 of 934 patients (84%). Logistic regression analysis showed increasing odds ratios (ORs) for the highest risk category for new-onset acute kidney injury (OR, 7.37; 95% CI, 2.58-21.08); new dialysis need (OR, 8.13; 95% CI, 1.74-37.91); ICU mortality (OR, 16.39; 95% CI, 5.99-44.87); and hospital mortality (OR, 18.65; 95% CI, 6.81-51.11). Although not increasing progressively, the OR for the highest risk group was significantly associated with new-onset hypovolemic shock (OR, 6.06; 95% CI, 1.47-25.00). With increasing HYPSs, median values (interquartile ranges) decreased progressively (lowest risk vs. highest risk) for ventilator-free days (23 [18-26] vs. 1 [0-21], P < .001) and ICU-free days (20 [11-24] vs. 0 [0-13], P < .001). Of the 729 patients in the stable subset, 598 (82%) had complete data for HYPS calculations. Logistic regression analysis showed significantly increasing ORs for the highest risk category for new-onset hypovolemic shock (OR, 7.41; 95% CI, 2.06-26.62); ICU mortality (OR, 5.08; 95% CI, 1.87-13.85); and hospital mortality (OR, 7.08; 95% CI, 2.63-19.07).

CONCLUSIONS

As the risk for peri-intubation hypotension increases, according to a validated hypotension prediction tool, so does the risk for adverse clinical events and certain clinical conditions.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov (NCT02508948).

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.

A Review of Push-Dose Vasopressors in the Peri-operative and Critical Care Setting

During hospitalization, the risk of hypotension and associated sequelae remain important considerations for patient outcomes. The use of push-dose vasopressors (PDP) outside of the operating room has increased in recent years to combat the negative effects of hypotension. This narrative review evaluates the utility of PDP in its traditional perioperative setting as well as in areas of increasing use such as the emergency department and intensive care unit. Articles evaluating PDP highlight successful increases in blood pressure with all agents but differ in rates of adverse events and most lack direct comparison of PDP agents in regard to safety and efficacy. Agents utilized as PDP, including epinephrine, phenylephrine, norepinephrine, vasopressin, and ephedrine vary in mechanism of action, onset of action, and duration of action. These variations in pharmacology along with published literature may lead to differences in the preferred PDP for various clinical scenarios. Many adverse events associated with PDP have been due to dosing errors highlighting the importance of education surrounding the use of these agents. Additional research is necessary to further elucidate the risks and benefits of PDP in clinical practice, and to determine which PDP is truly preferred. Careful consideration should be given when determining the appropriateness of this administration method of vasopressors in various clinical scenarios.

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.

Neuromuscular blockade and airway management during endotracheal intubation in Brazilian intensive care units: a national survey

OBJECTIVE

To describe the use of neuromuscular blockade as well as other practices among Brazilian physicians in adult intensive care units.

METHODS

An online national survey was designed and administered to Brazilian intensivists. Questions were selected using the Delphi method and assessed physicians' demographic data, intensive care unit characteristics, practices regarding airway management, use of neuromuscular blockade and sedation during endotracheal intubation in the intensive care unit. As a secondary outcome, we applied a multivariate analysis to evaluate factors associated with the use of neuromuscular blockade.

RESULTS

Five hundred sixty-five intensivists from all Brazilian regions responded to the questionnaire. The majority of respondents were male (65%), with a mean age of 38 ( 8.4 years, and 58.5% had a board certification in critical care. Only 40.7% of the intensivists reported the use of neuromuscular blockade during all or in more than 75% of endotracheal intubations. In the multivariate analysis, the number of intubations performed monthly and physician specialization in anesthesiology were directly associated with frequent use of neuromuscular blockade. Etomidate and ketamine were more commonly used in the clinical situation of hypotension and shock, while propofol and midazolam were more commonly prescribed in the situation of clinical stability.

CONCLUSION

The reported use of neuromuscular blockade was low among intensivists, and sedative drugs were chosen in accordance with patient hemodynamic stability. These results may help the design of future studies regarding airway management in Brazil.

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.

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.

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.

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.

Mortality Related to Intubation in Adult General ICUs: A Systematic Review and Meta-Analysis

Context: Mortality related to intubation occurs as a result of multiple factors such as patient's condition, operator's skills, equipment use, intubation time, duration of laryngoscopy and intubation, and drugs and dosage used for endotracheal intubation (ETI). Objectives: This systematic review and meta-analysis aimed to determine mortality related to intubation and the overall intensive care unit (ICU) mortality rate in adult general ICUs. Methods: We performed a systematic review and meta-analysis on randomized clinical trials and cohort and cross-sectional research from three electronic databases with hand searching. The studies reported mortality related to intubation and the overall ICU mortality rate in adult general ICUs. Our search resulted in 28 published articles without any restriction on date and language. The systematic review and meta-analysis was performed to examine mortality related to intubation and the overall ICU mortality rate. Results: We found 7,866 articles in the literature review from the three databases based on our keywords, of which 28 studies were eligible to include in the study. We observed that mortality related to intubation and the overall ICU mortality rate in intubated patients were 1% and 30%, respectively. Conclusions: This was the first comprehensive systematic review on mortality related to intubation and the overall ICU mortality rate in adult general ICUs, which showed the current care of ETI. However, it was associated with increased complications, which may increase mortality.

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.

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.

Co-induction with a vasopressor "chaser" to mitigate propofol-induced hypotension when intubating critically ill/frail patients-A questionable practice

Prophylactic administration of a vasopressor to mitigate the hypotensive effect of propofol (and/or other co-induction agents) during sedation/anesthesia immediately prior to tracheal intubation in frail patients in the intensive care unit and emergency and operating rooms appears to be not an uncommon practice. We submit that this practice is unnecessary and potentially harmful. Despite restoring the blood pressure, phenylephrine, for instance, may have an additive or synergistic effect with propofol in reducing the cardiac output and, ultimately, organ perfusion. Airway instrumentation often leads to sympathetic activation and hypertension (thereby increasing myocardial oxygen consumption) which may be exacerbated by an arbitrary prophylactic dose of phenylephrine. Finally, in spite of the well-recognized need to reduce dosages of propofol in frail patients, excessive doses are commonly given, leading to hypotension. We herein discuss each of these points and suggest alternative techniques to promote a stable induction in frail patients.

Risk factors associated with inpatient cardiac arrest during emergency endotracheal intubation at general wards

Background:

Peri-intubation cardiac arrest (PICA) following emergent endotracheal intubation (ETI) is a rare, however, potentially preventable type of cardiac arrest. Limited published data have described factors associated with inpatient PICA and patient outcomes. The aim of this study was to identify risk factors associated with PICA among hospitalized patients emergently intubated at a general ward as compared to non-PICA inpatients. In addition, we identified a difference of clinical outcomes in patients between PICA and other types of inpatient cardiac arrest (OTICA).

Methods:

We conducted a retrospective observational study of patients at two institutions between January 2016 to December 2017. PICA was defined in patients emergently intubated who experienced cardiac arrest within 20 minutes after ETI. The non-PICA group consisted of inpatients emergently intubated without cardiac arrest. Risk factors for PICA were identified through univariate and multivariate logistic regression analysis. Clinical outcomes were compared between PICA and OTICA.

Results:

Fifteen episodes of PICA occurred during the study period, accounting for 3.6% of all inpatient arrests. Intubation-related shock index, number of intubation attempts, pre-ETI vasopressor use, and neuromuscular blocking agent (NMBA) use, especially succinylcholine, were independently associated with PICA. Clinical outcomes of intensive care unit and hospital length of stay, survival to discharge, and neurologic outcome at hospital discharge were not significantly different between PICA and OTICA.

Conclusions:

We identified four independent risk factors for PICA, and preintubation hemodynamic stabilization and avoidance of NMBA were possibly correlated with a decreased PICA risk. Clinical outcomes of PICA were similar to those of OTICA.

Meta-Analysis of Post-Intubation Hypotension: A Plea to Consider Circulation First in Hypovolemic Patients

Hypovolemic patients can develop postintubation hypotension (PIH). Our objective is to review the literature regarding PIH and the association with mortality. We searched MEDLINE from inception to February 2018. A meta-analysis was performed to assess the effect of PIH on mortality. The results of the meta-analysis were reported in forest plots of the estimated effects of the included studies with a 95 per cent confidence interval. Heterogeneity was evaluated using the I2 test, which corresponded to low (I2 < 25%), medium (I2 = 25–75%), and high (I2 > 75%) heterogeneity. We identified 243 records. Four studies were included in the meta-analysis. The studies reported 2044 patients with 36.8 per cent (n = 753) developing PIH. Data indirectly reflecting the hemodynamic status were available in three studies (n = 1117 patients). Overall mortality was 24.6 per cent (n = 503) and was significantly higher in patients that developed PIH [mortality, n (%): PIH = 250/753 (33.2%) vs 253/1291 (19.6%), P < 0.001]. Patients that develop PIH have an increased mortality. Considering a targeted resuscitation in hypovolemic patients is pivotal to minimize PIH.

Shock Index as a Predictor of Post-Intubation Hypotension and Cardiac Arrest; A Review of the Current Evidence

Endotracheal intubation is a lifesaving procedure that is performed in various settings within the hospital or even in the pre-hospital field. However, it can result in serious hemodynamic complications, such as post-intubation hypotension (PIH) and cardiac arrest. The most promising predictor of such complications is the shock index (SI), which holds great prognostic value for multiple disorders. On the other hand, most of the studies that have assessed the predictability of the pre-intubation SI have been small and were limited to a particular setting of a single center; thus, the results were not generalizable, and the predictive value vary according to the setting. This review comprehensively assessed the utility of the pre-intubation SI for predicting PIH and post-intubation cardiac arrest by classifying and comparing evidence compiled from various settings, such as pre-hospital settings, emergency departments (EDs), intensive care units (ICUs), and operating rooms (ORs). The vast majority of these studies, conducted in ED and ICU settings, which revealed a significant correlation between an elevated SI and PIH or post-intubation cardiac arrest. The reliability and simplicity of obtaining a pre-intubation SI value are important considerations that encourage the extension of its use to all in-hospital intubations. Further studies are required to assess the predictive value of the SI in the pre-hospital setting.

Endotracheal Intubation Among the Critically Ill: Protocol for a Multicenter, Observational, Prospective Study

Background

Endotracheal intubation can occur in up to 60% of critically ill patients. Despite the frequency with which endotracheal intubation occurs, the current practice is largely unknown. This is relevant, as advances in airway equipment (ie, video laryngoscopes) have become more prevalent, leading to possible improvement of care delivered during this process. In addition to new devices, a greater emphasis on airway plans and choices in sedation have evolved, although the influence on patient morbidity and mortality is largely unknown.

Objective

This study aims to derive and validate prediction models for immediate airway and hemodynamic complications of intensive care unit intubations.

Methods

A multicenter, observational, prospective study of adult critically ill patients admitted to both medical and surgical intensive care units (ICUs) was conducted. Participating ICU sites were located throughout eight health and human services regions of the United States for which endotracheal intubation was needed. A steering committee composed of both anesthesia and pulmonary critical care physicians proposed a core set of data variables. These variables were incorporated into a data collection form to be used within the multiple, participating ICUs across the United States during the time of intubation. The data collection form consisted of two basic components, focusing on airway management and hemodynamic management. The form was generated using RedCap and distributed to the participating centers. Quality checks on the dataset were performed several times with each center, such that they arrived at less than 10% missing values for each data variable; the checks were subsequently entered into a database.

Results

The study is currently undergoing data analysis. Results are expected in November 2018 with publication to follow thereafter. The study protocol has not yet undergone peer review by a funding body.

Conclusions

The overall goal of this multicenter prospective study is to develop a scoring system for peri-intubation, hemodynamic, and airway-related complications so we can stratify those patients at greatest risk for decompensation as a result of these complications. This will allow critical care physicians to be better prepared in addressing these occurrences and will allow them to improve the quality of care delivered to the critically ill.

Trial Registration

ClinicalTrials.gov NCT02508948; https://clinicaltrials.gov/ct2/show/NCT02508948 (Archived by WebCite at http://www.webcitation.org/73Oj6cTFu)

International Registered Report Identifier (IRRID)

RR1-10.2196/11101

Sedative dose and patient variable impacts on postintubation hypotension in emergency airway management

PURPOSE

Postintubation hypotension (PIH) is an adverse event associated with poor outcomes in emergency department (ED) endotracheal intubation. This study aimed to evaluate the association between sedative dose adjustment and PIH during emergency airway management. We also investigated the impact of patient and procedural factors on the incidence of PIH.

MATERIALS AND METHODS

This was a single-center, retrospective study that used a prospectively collected registry of airway management performed at the ED from April 2014 to February 2017. Adult patients who received emergency endotracheal intubation were included. Multivariable logistic regression models were used to evaluate the association of PIH with sedative dose, patient variables, and procedural variables.

RESULTS

Overall, 689 patients were included, and 233 (33.8%) patients developed PIH. In the patients overall, multivariable logistic regression demonstrated that age > 70 years, shock index >0.8, arterial acidosis (pH < 7.2), intubation indication, and use of non-depolarizing neuromuscular blocking agent were significantly related to PIH. In patients overall, the sedative dose was not related to PIH (overdose; OR: 1.09, 95%CI: 0.57-2.06), (reduction; OR: 0.93, 95%CI: 0.61-1.42), (none used; OR: 1.28, 95%CI: 0.64-2.53). In subgroup analysis, ketamine dose was not related to PIH (overdose; OR: 0.81, 95%CI: 0.27-2.38, reduction; OR: 1.41, 95%CI: 0.78-2.54). Reduction of etomidate dose was significantly associated with decreased PIH (reduction; OR: 0.46, 95%CI: 0.22-0.98, overdose; OR: 1.77, 95%CI: 0.79-3.93).

CONCLUSIONS

PIH was mainly related to predisposing patient-related factors. Only adjustment of etomidate dose was associated with the incidence of PIH.