First Pass Success Without Hypoxemia Is Increased With the Use of Apneic Oxygenation During Rapid Sequence Intubation in the Emergency Department

Pre-oxygenation using high-flow nasal oxygen versus tight facemask in trauma patients undergoing emergency anaesthesia

BACKGROUND

Patients suffering from major traumatic injuries frequently require emergency anaesthesia. Due to often compromised physiology and the time-sensitive management, trauma patients may be more prone to desaturate during induction of anaesthesia. We hypothesised that pre-oxygenation using high-flow nasal oxygen would decrease the risk of desaturation during induction of anaesthesia in trauma patients and the study therefore aimed to compare the frequency of desaturation when pre-oxygenation was performed with high-flow nasal oxygen or a traditional facemask.

METHODS

This exploratory, prospective, before-and-after study was conducted at the Karolinska University Hospital, Sweden. Adult (≥18 years of age) patients suffering major traumatic injuries needing emergency anaesthesia were included around the clock. Patients were pre-oxygenated using a tight-fitting facemask during the first nine months of enrollment. High-flow nasal oxygen was then introduced as a method for pre-oxygenation of trauma patients. The primary outcome was the proportion of patients desaturating <93% during induction of anaesthesia, assessed from the start of pre-oxygenation until one minute after intubation. Secondary outcomes included perceived difficulty of pre-oxygenation among anaesthetists (assessed on a scale between 1 and 10) and safety outcomes, such as incidence of regurgitations and intracranial gas (assessed radiologically).

RESULTS

Data from 96 patients were analysed. Facemask pre-oxygenation was performed in 66 patients, while 30 patients were pre-oxygenated with high-flow nasal oxygen. The most frequent trauma mechanisms were stabbing injuries (n = 34 (35%)) and fall injuries (n = 21 (22%)). There were no differences in patient characteristics between the groups. Eight (12%) versus three (10%) patients desaturated <93% in the facemask and high-flow nasal oxygen group respectively, OR 0.81 (95% CI 0.20-3.28), p = .76. Anaesthetists assessed pre-oxygenation using high-flow nasal oxygen as easier compared to facemask pre-oxygenation. No patient in any group showed signs of regurgitation. Among patients with facial or skull fractures requiring anaesthesia before radiology was performed, intracranial gas was seen in four (40%) patients pre-oxygenated with a facemask and in no patient pre-oxygenated with HFNO (p = .23).

CONCLUSION

In this prospective study investigating trauma patients undergoing emergency anaesthesia, we could not see any difference in the number of patients desaturating when pre-oxygenation was performed with high-flow nasal oxygen compared to a tight-fitting facemask. Pre-oxygenation using high-flow nasal oxygen was assessed as easier compared to facemask pre-oxygenation.

Diagnosis and Management of Acute Respiratory Failure

Acute hypoxemic respiratory failure is defined by Pao2 less than 60 mm Hg or SaO2 less than 88% and may result from V/Q mismatch, shunt, hypoventilation, diffusion limitation, or low inspired oxygen tension. Acute hypercapnic respiratory failure is defined by Paco2 ≥ 45 mm Hg and pH less than 7.35 and may result from alveolar hypoventilation, increased fraction of dead space, or increased production of carbon dioxide. Early diagnostic maneuvers, such as measurement of SpO2 and arterial blood gas, can differentiate the type of respiratory failure and guide next steps in evaluation and management.

Bed tilt and ramp positions are associated with increased first-pass success of adult endotracheal intubation in the emergency department: A registry study

OBJECTIVE

Successful endotracheal intubation in the ED requires optimum body positioning. In patients with obesity, the ramp position was suggested to achieve better intubating conditions. However, limited data are available on the airway management practices for patients with obesity in Australasian EDs. The aim of this study was to identify current patient positioning practices during endotracheal intubation and its association with first-pass success (FPS) at intubation and adverse event (AE) rates in obese and non-obese populations.

METHODS

Prospectively collected data from the Australia and New Zealand ED Airway Registry (ANZEDAR) between 2012 and 2019 were analysed. Patients were categorised into two groups according to their weight: <100 kg (non-obese) or ≥100 kg (obese). Four position categories were investigated; supine, pillow or occipital pad, bed tilt and ramp or head-up with relation to FPS and complication rate using logistic regression modelling.

RESULTS

A total of 3708 intubations from 43 EDs were included. Overall, the non-obese cohort had a greater FPS rate (85.9%) compared to the obese group (77.0%). The bed tilt position had the highest FPS rate (87.2%), whereas the supine position had the lowest (83.0%). AE rates were highest in the ramp position (31.2%) compared to all other positions (23.8%). Regression analysis showed ramp, or bed tilt positions and a consultant-level intubator were associated with higher FPS. Obesity, in addition to other factors, was independently associated with lower FPS.

CONCLUSION

Obesity was associated with lower FPS, which could be improved through performing a bed tilt or ramp positioning.

Evaluation of tracheal intubations in a paediatric intensive care unit

INTRODUCTION

Tracheal intubation is a frequent procedure in paediatric intensive care units (PICUs) that carries a risk of complications that can increase morbidity and mortality.

PATIENTS AND METHODS

Prospective, longitudinal, observational study in patients intubated in a level III PICU between January and December 2020. We analysed the risk factors associated with failed intubation and adverse events.

RESULTS

The analysis included 48 intubations. The most frequent indication for intubation was hypoxaemic respiratory failure (25%). The first attempt was successful in 60.4% of intubations, without differences between procedures performed by staff physicians and resident physicians (62.5% vs 56.3%; P = .759). Difficulty in bag-mask ventilation was associated with failed intubation in the first attempt (P = .028). Adverse events occurred in 12.5% of intubations, and severe events in 8.3%, including 1 case of cardiac arrest, 2 cases of severe hypotension and 1 of oesophageal intubation with delayed recognition. None of the patients died. Making multiple attempts was significantly associated with adverse events (P < .002). Systematic preparation of the procedure with cognitive aids and role allocation was independently associated with a lower incidence of adverse events.

CONCLUSIONS

In critically ill children, first-attempt intubation failure is common and associated with difficulty in bag-mask ventilation. A significant percentage of intubations may result in serious adverse events. The implementation of intubation protocols could decrease the incidence of adverse events.

The efficacy of apneic oxygenation to prevent hypoxemia during rapid sequence intubation in trauma patients

PURPOSE OF REVIEW

Rapid and effective airway management is priority for trauma patients. Trauma patients are often at an increased risk of experiencing hypoxia, and thus at increased risk of morbidity and mortality. Apneic oxygenation has been widely debated but has been reported to provide benefit in terms of increased peri-intubation oxygen saturation and decreased rates of desaturation. This review aims to evaluate the current literature on the efficacy of apneic oxygenation in the setting of rapid sequence intubation (RSI) in trauma patients.

RECENT FINDINGS

Two prospective studies published this year, demonstrated that apneic oxygenation was effective in reducing hypoxic events and hypoxic duration during RSI.

SUMMARY

The use of apneic oxygenation can play an important role in preventing hypoxic events in trauma patients undergoing RSI. The use of apneic oxygenation is cheap, and should be considered to reduce hypoxemic events. Additional studies are required to see the effects of apneic oxygenation on outcomes in trauma patients undergoing RSI, specifically desaturation and hypoxemic events and duration, and early onset mortality.

Video screen visualization patterns when using a video laryngoscope for tracheal intubation: A systematic review

OBJECTIVE

Published studies of video laryngoscopes are often limited by the lack of a clear definition of video laryngoscopy (VL). We performed a systematic review to determine how often published studies of VL report on video screen visualization.

METHODS

We searched PubMed, EMBASE and Scopus for interventional and observational studies in which a video laryngoscope equipped with a standard geometry blade was used for tracheal intubation. We excluded simulation based studies. Our primary outcome was data on video laryngoscope screen visualization. Secondary outcomes were explicit methodology for screen visualization.

RESULTS

We screened 4838 unique studies and included 207 (120 interventional and 87 observational). Only 21 studies (10% of 207) included any data on video screen visualization by the proceduralist, 19 in a yes/no fashion only (ie, screened viewed or not) and 2 with detail beyond whether the screen was viewed or not. In 11 more studies, visualization patterns could be inferred based on screen availability and in 16 more studies, the methods section stated how screen visualization was expected to be performed without reporting data collection on how the proceduralist interacted with the video screen. Risk of bias was high in the majority of included studies.

CONCLUSIONS

Published studies of VL, including many clinical trials, rarely include data on video screen visualization. Given the nuances of using a video laryngoscope, this is a critical deficiency, which largely prevents us from knowing the treatment effect of using a video laryngoscope in clinical practice. Future studies of VL must address this deficiency.

Improving first-pass success rates during emergency intubation at an academic emergency department: a quality improvement initiative

BACKGROUND

Airway management is a high-stakes procedure in emergency medicine. Continuously monitoring this procedure allows performance improvement while revealing safety issues. We instituted a quality improvement initiative in the emergency department to improve first-pass success rates in the emergency department.

METHODS

This was a quality improvement initiative at an academic emergency department from 2018 to 2020. We developed a rapid sequence intubation guideline for procedure standardization and introduced an intubation procedure note for performance monitoring. Data were entered directly by the primary physician and nurse during intubation. The quality improvement team thereafter collected the data retrospectively and entered into a local airway database. More importantly, we introduced a culture of quality improvement and safety in airway management via regular education and feedback.

RESULTS

We included a total of 146 intubations. The first-pass success rate started at 57.1% and increased to 80.0% during the study period (P < 0.01). Fifty-six percent were male, and the mean age (±SD) was 55.56 (±17.64). Video laryngoscopy was used in 101 (69.2%) patients, while direct laryngoscopy was used in only 44 (30.8%) patients. A logistic regression analysis was conducted to determine the independent factors associated with first-pass success. These factors included the use of video laryngoscopy (odds ratio (OR) 2.47 95% confidence interval (95% CI) [1.62-3.76]) (adjusted OR 3.87 [1.13-13.23]) and good Cormack-Lehane views (grades 1-2) (OR 2.71 95% CI [1.74-4.20]) (adjusted OR 7.88 [2.43-25.53]).

CONCLUSION

Our study shows that implementing and maintaining an airway quality improvement program improves first-pass intubation success. Moreover, the use of video laryngoscopy and obtaining good Cormack-Lehane views (grades 1-2) are independently associated with improved first-pass success.

Predictors of first pass success without hypoxemia in trauma patients requiring emergent rapid sequence intubation

Objective

The predictors of first pass success (FPS) without hypoxemia among trauma patients requiring rapid sequence intubation (RSI) in the emergent setting are unknown.

Methods

Retrospective study of adult trauma patients requiring RSI during a 5-year period comparing the trauma patients achieving FPS without hypoxemia to those who did not. The primary outcome was FPS without hypoxemia evaluated by multivariate logistic regression adjusting for the neuromuscular blocking agent used (succinylcholine or rocuronium), hypoxemia prior to RSI, Glasgow Coma Scale (GCS) scores, the presence of head or facial trauma, and intubating operator level of training.

Results

246 patients met our inclusion criteria. The overall FPS rate was 89%, and there was no statistical difference between those receiving either paralytic agent. 167 (69%) patients achieved FPS without hypoxemia. The two groups (those achieving FPS without hypoxemia and those who did not) had similar mean GCS, mean Injury Severity Scores, presence of head or facial trauma, the presence of penetrating trauma, intubating operator-level training, use of direct laryngoscopy, hypoxemia prior to RSI, heart rate per minute, mean systolic blood pressure, and respiratory rate. In the multivariate regression analysis, the use of succinylcholine and GCS score of 13–15 were found to have adjusted ORs of 2.1 (95% CI 1.2 to 3.8) and 2.0 (95% CI 1.0 to 3.3) for FPS without hypoxemia, respectively.

Conclusion

Trauma patients requiring emergency department RSI with high GCS score and those who received succinylcholine had higher odds of achieving FPS without hypoxemia, a patient safety goal requiring more study.

Level of evidence

IV.

Study type

Prognostic.

Unintended consequences: The impact of airway management modifications introduced in response to COVID-19 on intubations in a tertiary centre emergency department

Objective

In response to COVID‐19, we introduced and examined the effect of a raft of modifications to standard practice on adverse events and first‐attempt success (FAS) associated with ED intubation.

Methods

An analysis of prospectively collected registry data of all ED intubations over a 3‐year period at an Australian Major Trauma Centre. During the first 6 months of the COVID‐19 pandemic in Australia, we introduced modifications to standard practice to reduce the risk to staff including: aerosolisation reduction, comprehensive personal protective equipment for all intubations, regular low fidelity simulation with ‘sign‐off’ for all medical and nursing staff, senior clinician laryngoscopist and the introduction of pre‐drawn medications.

Results

There were 783 patients, 136 in the COVID‐19 era and 647 in the pre‐COVID‐19 comparator group. The rate of hypoxia was higher during the COVID‐19 era compared to pre‐COVID‐19 (18.4% vs 9.6%, P < 0.005). This occurred despite the FAS rate remaining very high (95.6% vs 93.8%, P = 0.42) and intubation being undertaken by more senior laryngoscopists (consultant 55.9% during COVID‐19 vs 22.6% pre‐COVID‐19, P < 0.001). Other adverse events were similar before and during COVID‐19 (hypotension 12.5% vs 7.9%, P = 0.082; bradycardia 1.5% vs 0.5%, P = 0.21). Video laryngoscopy was more likely to be used during COVID‐19 (95.6% vs 82.5%, P < 0.001) and induction of anaesthesia more often used ketamine (66.9% vs 42.3%, P < 0.001) and rocuronium (86.8% vs 52.1%, P < 0.001).

Conclusions

This raft of modifications to ED intubation was associated with significant increase in hypoxia despite a very high FAS rate and more senior first laryngoscopist.

Safety of rapid sequence intubation in an emergency training network

OBJECTIVE

Rapid sequence intubation (RSI) is a core critical care skill. Emergency medicine trainees are exposed to relatively low numbers of RSIs. We aimed to improve patient outcomes by implementing an RSI checklist, electronic learning and audit, in line with current best evidence.

METHODS

Prospective observational study of RSIs performed in the EDs of two Queensland hospitals between January 2014 and December 2016. Data collected included: first-pass success (FPS), predicted difficulty, indication for intubation, drugs used, positioning, number of attempts, checklist use and complications. Descriptive statistics and multivariable modelling were used to describe differences in FPS, and complications.

RESULTS

Six hundred and fifty-five patients underwent RSI with FPS of 86.6%. Complications were reported in 15.9%, mainly hypotension (10.9%) and desaturation (4.0%). FPS improved with bougie use (88.9% vs 73.0% without bougie, P < 0.001) and video-laryngoscopy (88.2% vs 72.9% using standard laryngoscopy, P < 0.001). New desaturation was reduced with apnoeic oxygenation (2.0% vs 22.2%, P < 0.001), bougie use (2.8% vs 8.9%, P < 0.001), checklist use (2.3% vs 22.7%, P < 0.001) and achieving FPS (2.1% vs 16.3%, P < 0.001). Complications were reduced with checklist use (13.3% vs 43.2%, P < 0.001) and apnoeic oxygenation use (3.9% vs 31.1%, P < 0.001). Logistic regression found checklist use was associated with reduced desaturation (OR 0.1, 95% CI 0.04-0.27) and the composite variable of any complication (OR 0.39, 95% CI 0.17-0.89).

CONCLUSIONS

Implementation of an evidence-based care bundle and audit of practice has created a safe environment for trainees to learn the core critical care skill of RSI. In our setting, checklist use was associated with fewer complications.

Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 2. Planning and implementing safe management of the patient with an anticipated difficult airway

PURPOSE

Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the published airway management literature has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This second of two articles addresses airway evaluation, decision-making, and safe implementation of an airway management strategy when difficulty is anticipated.

SOURCE

Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence is lacking, statements are based on group consensus.

FINDINGS AND KEY RECOMMENDATIONS

Prior to airway management, a documented strategy should be formulated for every patient, based on airway evaluation. Bedside examination should seek predictors of difficulty with face-mask ventilation (FMV), tracheal intubation using video- or direct laryngoscopy (VL or DL), supraglottic airway use, as well as emergency front of neck airway access. Patient physiology and contextual issues should also be assessed. Predicted difficulty should prompt careful decision-making on how most safely to proceed with airway management. Awake tracheal intubation may provide an extra margin of safety when impossible VL or DL is predicted, when difficulty is predicted with more than one mode of airway management (e.g., tracheal intubation and FMV), or when predicted difficulty coincides with significant physiologic or contextual issues. If managing the patient after the induction of general anesthesia despite predicted difficulty, team briefing should include triggers for moving from one technique to the next, expert assistance should be sourced, and required equipment should be present. Unanticipated difficulty with airway management can always occur, so the airway manager should have a strategy for difficulty occurring in every patient, and the institution must make difficult airway equipment readily available. Tracheal extubation of the at-risk patient must also be carefully planned, including assessment of the patient's tolerance for withdrawal of airway support and whether re-intubation might be difficult.

Apnoeic oxygenation was associated with decreased desaturation rates during rapid sequence intubation in multiple Australian and New Zealand emergency departments

Apnoeic oxygenation (ApOx) has been demonstrated to reduce the incidence of desaturation, although evidence of benefit has been conflicting depending on the technique used. The aim of this study was to compare the incidence of desaturation between patients who received ApOx via conventional nasal cannula (NC) and those who did not, using a large, multicentre airway registry.

METHODS

This study is an analysis of 24 months of prospectively collected data in the Australia and New Zealand Emergency Department Airway Registry (June 2013-June 2015). The registry includes information on all intubated adults from 43 emergency departments. Patients intubated during cardiac arrest (n=393), those who received active ventilation prior to the first intubation attempt (n=486), and where the use of ApOx was not recorded either way (n=312) were excluded. The proportion of patients who desaturated (Sa0₂ <93) in the group that received ApOx and those that did not were compared. To evaluate the association of ApOx with patient desaturation, a logistic regression model based on factors expected to influence desaturation was performed.

RESULTS

Of 2519 patients analysed, 1669 (66.3%) received ApOx via NC while 850 (33.7%) did not. Desaturation in the cohort receiving ApOx was 10.4% compared with standard care (no ApOx) 13.7%. ApOx had a protective effect for desaturation (OR 0.71 95% CI 0.53 to 0.95). Single intubation attempt was associated with reduced risk of desaturation of (OR 0.10, 95% CI 0.06 to 0.17); this was increased on second attempt (OR 0.37, 95% CI 0.21 to 0.68). Desaturation was also associated with the physician recording that they had anticipated a difficult airway (OR 1.83, 95% CI 1.34 to 2.48).

CONCLUSION

This large multicentre registry study provides evidence that ApOx delivered through a conventional NC is associated with a lower incidence of desaturation in patients undergoing rapid sequence intubation.

TRIAL REGISTRATION NUMBER

ACTRN12613001052729.

Compared Efficacy of Four Preoxygenation Methods for Intubation in the ICU: Retrospective Analysis of McGrath Mac Videolaryngoscope Versus Macintosh Laryngoscope (MACMAN) Trial Data

OBJECTIVES

Severe hypoxemia is the most common serious adverse event during endotracheal intubation. Preoxygenation is performed routinely as a preventive measure. The relative efficacy of the various available preoxygenation devices is unclear. Here, our objective was to assess associations between preoxygenation devices and pulse oximetry values during endotracheal intubation.

DESIGN

Post hoc analysis of data from a multicenter randomized controlled superiority trial (McGrath Mac Videolaryngoscope Versus Macintosh Laryngoscope [MACMAN]) comparing videolaryngoscopy to Macintosh laryngoscopy for endotracheal intubation in critical care.

SETTING

Seven French ICUs.

PATIENTS

Three-hundred nineteen of the 371 critically ill adults requiring endotracheal intubation who were included in the MACMAN trial.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Minimal pulse oximetry value during endotracheal intubation was the primary endpoint. We also sought risk factors for pulse oximetry below 90%. Of 319 patients, 157 (49%) had bag-valve-mask, 71 (22%) noninvasive ventilation, 71 (22%) non-rebreathing mask, and 20 (7%) high-flow nasal oxygen for preoxygenation. Factors independently associated with minimal pulse oximetry value were the Simplified Acute Physiology Score II severity score (p = 0.03), baseline pulse oximetry (p < 0.001), baseline PaO2/FIO2 ratio (p = 0.02), and number of laryngoscopies (p = 0.001). The only independent predictors of pulse oximetry less than 90% were baseline pulse oximetry (odds ratio, 0.71; 95% CI, 0.64-0.79; p < 0.001) and preoxygenation device: with bag-valve-mask as the reference, odds ratios were 1.10 (95% CI, 0.25-4.92) with non-rebreathing mask, 0.10 (95% CI, 0.01-0.80) with noninvasive ventilation, and 5.75 (95% CI, 1.15-28.75) with high-flow nasal oxygen.

CONCLUSIONS

Our data suggest that the main determinants of hypoxemia during endotracheal intubation may be related to critical illness severity and to preexisting hypoxemia. The differences across preoxygenation methods suggest that noninvasive ventilation may deserve preference in patients with marked hypoxemia before endotracheal intubation. Ongoing studies will provide further clarification about the optimal preoxygenation method for endotracheal intubation in critically ill patients.

Apneic nasal oxygenation and safe apnea time during pediatric intubations by learners

BACKGROUND

Apneic nasal oxygenation (ApOx) prolongs the time to desaturation during intubation of adult patients, but there is limited prospective evidence for apneic oxygenation in pediatric patients.

AIMS

We hypothesized that ApOx during operating room intubation of pediatric patients by inexperienced learners would prolong the interval before desaturation.

METHODS

This prospective observational study compared intubation data for 196 pediatric surgical patients intubated by learners under baseline practice (no nasal cannula), to 160 patients enrolled after adoption of routine apneic nasal cannula oxygenation at 5 L/min. The primary outcome was elapsed time between anesthetic induction and pulse oximetry (SpO₂ ) falling to 95, if ever.

RESULTS

Nasal cannula oxygenation during intubation by learners delayed desaturation to SpO₂ 95 (risk ratio for this event before intubation 0.05, 95% CI 0.03-0.09; P < 0.0001).

CONCLUSIONS

Apneic oxygenation via nasal cannula during intubation of pediatric surgical patients prolongs time before desaturation, thus extending the safe interval for airway management by learners.

Critical Care Airway Management

Critical care airway management is associated with a variety of complications, including severe oxygen desaturation, life-threatening hypotension, and death. This article reviews aspects of airway management that are relevant to intensivists and emergency medicine clinicians tasked with improving the quality of urgent endotracheal intubation in the critically ill patient.

Emergency Neurological Life Support: Airway, Ventilation, and Sedation

Airway management and ventilation are central to the resuscitation of the neurologically ill. These patients often have evolving processes that threaten the airway and adequate ventilation. Furthermore, intubation, ventilation, and sedative choices directly affect brain perfusion. Therefore, Airway, Ventilation, and Sedation was chosen as an Emergency Neurological Life Support protocol. Topics include airway management, when and how to intubate with special attention to hemodynamics and preservation of cerebral blood flow, mechanical ventilation settings and the use of sedative agents based on the patient's neurological status.

Changing the Emergency Department's Practice of Rapid Sequence Intubation to Reduce the Incidence of Hypoxia

Rapid sequence intubation (RSI) is an advanced procedure performed by nurse practitioners in the emergency department (ED). Hypoxia is one of the most common complications associated with RSI, which may lead to serious sequela, including death. Hypoxia may result from medications that are given to facilitate the procedure or the underlying disease process. Without preventive measures, oxygen levels may fall rapidly when patients are no longer actively breathing. The incidence of RSI-induced hypoxia may be mitigated with proper education, preoxygenation, positioning, and the utilization of passive (apneic) oxygenation. The purpose of this project was to determine whether RSI practice could be changed through education and implementation of an evidence-based protocol in the ED of a hospital in south central United States. Baseline practice was determined by chart audits and compared with practice after educational sessions and protocol implementation. Change occurred as evidenced by an increase in the utilization of all 3 hypoxia prevention interventions included in the protocol. Staff education and utilization of a protocol changed the care provided, which can influence patient outcomes and decrease the incidence of RSI-induced hypoxia.

Does apneic oxygenation prevent desaturation during emergency airway management? A systematic review and meta-analysis

RéSUMé: OBJECTIF: L'oxygénation apnéique (OA) par lunettes nasales est une méthode de prévention de la désaturation en oxygène au cours des intubations en urgence. L'objectif de cette revue systématique était de déterminer l'efficacité de l'OA sur la prévention de la désaturation en oxygène au cours des intubations en urgence.

SOURCE

Des recherches systématiques ont été effectuées dans trois bases de données électroniques (MEDLINE, EMBASE et CINAHL) pour identifier les études portant sur la prévention de la désaturation en oxygène au moyen de l'OA par lunettes nasales. Notre critère d'évaluation principal était l'incidence des désaturations telle que définie dans chaque étude; nous avons ensuite évalué l'incidence de la désaturation sévère en oxygène (SpO₂ < 80%). Une méta-analyse a été effectuée sur les études présentant des données sur la désaturation en oxygène telle que définie par chaque étude et chez des patients ayant une désaturation sévère pour générer une estimation groupée de l'effet.

CONSTATATIONS PRINCIPALES

Au total, 544 études ont été examinées, parmi lesquelles dix (2 322 patients) satisfaisaient tous les critères d'éligibilité. Comparativement à l'absence d'OA, l'utilisation de cette méthode a été associée à une réduction de la désaturation en oxygène (risque relatif [RR] : 0,76; intervalle de confiance à 95% [IC] : 0,61 à 0,95; P = 0,02), mais n'a pas été associée à une réduction de la désaturation sévère (RR, 0,65; IC à 95% : 0,38 à 1,11; P = 0,12). Néanmoins, il y avait une hétérogénéité significative des facteurs liés aux patients, des interventions et des définitions de la désaturation en oxygène entre les études.

CONCLUSION

Nos constatations suggèrent que l'OA par lunettes nasales est associée à un moindre risque de désaturation en oxygène au cours des intubations en urgence. Cependant, compte de tenu de l'hétérogénéité des études, d'autres essais de grande qualité sont nécessaires pour déterminer quels patients pourraient bénéficier de l'OA au cours des intubations d'urgence.

Development and Testing of a Novel Anaesthesia Induction/Ventilation Protocol for Patients With Cardiogenic Shock Complicating Acute Myocardial Infarction

BACKGROUND

Cardiogenic shock is a life-threatening condition and patients might require rapid sequence induction (RSI) and mechanical ventilation. In this study, we evaluated a new RSI/mechanical ventilation protocol in patients with acute myocardial infarction complicated by cardiogenic shock.

METHODS

We included consecutive adult patients who were transferred to the emergency department. The RSI protocol included 5 phases: preoxygenation, pretreatment, induction/paralysis, intubation, and mechanical ventilation (PPIIM). A posteriori, we selected historical patients managed with standard RSI as a control group. The primary outcome was hemodynamic derangement or hypoxemia from enrollment until intensive care unit (ICU) admission.

RESULTS

We studied 31 consecutive patients who were intubated using the PPIIM protocol and 22 historical controls. We found significant differences in systolic (85.32 ± 4.23 vs 71.72 ± 7.98 mm Hg; P < 0.0001), diastolic (58.84 ± 5.84 vs 39.05 ± 5.63 mm Hg; P < 0.0001), and mean arterial pressure (67.71 ± 4.90 vs 49.90 ± 5.66 mm Hg; P < 0.0001), as well as in partial pressure of oxygen (85.80 ± 19.82 vs 164.73 ± 43.07 mm Hg; P < 0.0001) between the PPIIM and control group at 5 minutes of automated ventilation. Also, statistically significant differences were observed in diastolic (59.74 ± 4.93 vs 47.86 ± 11.47 mm Hg; P < 0.0001) and mean arterial pressure (68.65 ± 4.10 vs 60.23 ± 11.67 mm Hg; P < 0.0001), as well as in partial pressure of oxygen (119.84 ± 50.57 vs 179.50 ± 42.17 mm Hg; P < 0.0001), and partial pressure of carbon dioxide (39.81 ± 10.60 vs 31.00 ± 9.30 mm Hg; P = 0.003) between the 2 groups at ICU admission. Compared with the control group, with PPIIM more patients survived to ICU admission (100% vs 77%) and hospital discharge (71% vs 31.8%), as well as at 90 days (51.6% vs 18.2%), and at 180 days (38.7% vs 13.6%).

CONCLUSIONS

The PPIIM protocol allows safe intubation of acute myocardial infarction patients with cardiogenic shock and improves hemodynamic and oxygenation parameters.

Apneic oxygenation reduces hypoxemia during endotracheal intubation in the pediatric emergency department

BACKGROUND

Apneic oxygenation (AO) has been evaluated in adult patients as a means of reducing hypoxemia during endotracheal intubation (ETI). While less studied in pediatric patients, its practice has been largely adopted.

OBJECTIVE

Determine association between AO and hypoxemia in pediatric patients undergoing ETI.

METHODS

Observational study at an urban, tertiary children's hospital emergency department. Pediatric patients undergoing ETI were examined during eras without (January 2011-June 2011) and with (August 2014-March 2017) apneic oxygenation. The primary outcome was hypoxemia, defined as pulse oximetry (SpO₂) < 90%. The χ² and Wilcoxon rank-sum tests examined differences between cohorts. Multivariable regression models examined adjusted associations between covariates and hypoxemia.

RESULTS

149 patients were included. Cohorts were similar except for greater incidence of altered mental status in those receiving AO (26% vs. 7%, p = 0.03). Nearly 50% of the pre-AO cohort experienced hypoxemia during ETI, versus <25% in the AO cohort. Median [IQR] lowest SpO₂ during ETI was 93 (69, 99) for pre-AO and 100 [95, 100] for the AO cohort (p < 0.001). In a multivariable logistic regression model, hypoxemia during ETI was associated with AO (aOR 0.3, 95% confidence interval [CI] 0.1-0.8), increased age (for 1 year, aOR 0.8, 95% CI 0.7-1.0), lowest SpO₂ before ETI (for 1% increase, aOR 0.9, 95% CI 0.8-1.0), and each additional intubation attempt (aOR 4.0, 95% CI 2.2-7.2).

CONCLUSIONS

Apneic oxygenation is an easily-applied intervention associated with decreases in hypoxemia during pediatric ETI. Nearly 50% of children not receiving AO experienced hypoxemia.

Apneic oxygenation provides incremental benefit during intubation of patients in the emergency medicine and critical care settings

Clinical questionShould I use apneic oxygenation when intubating patients in the emergency department to increase peri-intubation oxygen saturation and first-pass success?Article chosenOliveira JE, Silva L, Cabrera D, Barrionuevo P, et al. Effectiveness of apneic oxygenation during intubation: a systematic review and meta-analysis. Ann Emerg Med 2017;70(4):483-94.

OBJECTIVE

The purpose of this study was to synthesize and appraise the apneic oxygenation literature for its effect on peri-intubation outcomes.

Implementation of a Clinical Bundle to Reduce Out-of-Hospital Peri-intubation Hypoxia

STUDY OBJECTIVE

Peri-intubation hypoxia is an important adverse event of out-of-hospital rapid sequence intubation. The aim of this project is to determine whether a clinical bundle encompassing positioning, apneic oxygenation, delayed sequence intubation, and goal-directed preoxygenation is associated with decreased peri-intubation hypoxia compared with standard out-of-hospital rapid sequence intubation.

METHODS

We conducted a retrospective, before-after study using data from a suburban emergency medical services (EMS) system in central Texas. The study population included all adults undergoing out-of-hospital intubation efforts, excluding those in cardiac arrest. The before-period intervention was standard rapid sequence intubation using apneic oxygenation at flush flow, ketamine, and a paralytic. The after-period intervention was a care bundle including patient positioning (elevated head, sniffing position), apneic oxygenation, delayed sequence intubation (administration of ketamine to facilitate patient relaxation and preoxygenation with a delayed administration of paralytics), and goal-directed preoxygenation. The primary outcome was the rate of peri-intubation hypoxia, defined as the percentage of patients with a saturation less than 90% during the intubation attempt.

RESULTS

The before group (October 2, 2013, to December 13, 2015) included 104 patients and the after group (August 8, 2015, to July 14, 2017) included 87 patients. The 2 groups were similar in regard to sex, age, weight, ethnicity, rate of trauma, initial oxygen saturation, rates of initial hypoxia, peri-intubation peak SpO₂, preintubation pulse rate and systolic blood pressure, peri-intubation cardiac arrest, and first-pass and overall success rates. Compared with the before group, the after group experienced less peri-intubation hypoxia (44.2% versus 3.5%; difference -40.7% [95% confidence interval -49.5% to -32.1%]) and higher peri-intubation nadir SpO₂ values (100% versus 93%; difference 5% [95% confidence interval 2% to 10%]).

CONCLUSION

In this single EMS system, a care bundle encompassing patient positioning, apneic oxygenation, delayed sequence intubation, and goal-directed preoxygenation was associated with lower rates of peri-intubation hypoxia than standard out-of-hospital rapid sequence intubation.

Nasal Cannula Apneic Oxygenation Prevents Desaturation During Endotracheal Intubation: An Integrative Literature Review

Patients requiring emergency airway management may be at greater risk of acute hypoxemic events because of underlying lung pathology, high metabolic demands, insufficient respiratory drive, obesity, or the inability to protect their airway against aspiration. Emergency tracheal intubation is often required before complete information needed to assess the risk of procedural hypoxia is acquired (i.e., arterial blood gas level, hemoglobin value, or chest radiograph). During pre-oxygenation, administering high-flow nasal oxygen in addition to a non-rebreather face mask can significantly boost the effective inspired oxygen. Similarly, with the apnea created by rapid sequence intubation (RSI) procedures, the same high-flow nasal cannula can help maintain or increase oxygen saturation during efforts to secure the tube (oral intubation). Thus, the use of nasal oxygen during pre-oxygenation and continued during apnea can prevent hypoxia before and during intubation, extending safe apnea time, and improve first-pass success attempts. We conducted a literature review of nasal-cannula apneic oxygenation during intubation, focusing on two components: oxygen saturation during intubation, and oxygen desaturation time. We performed an electronic literature search from 1980 to November 2017, using PubMed, Elsevier, ScienceDirect, and EBSCO. We identified 14 studies that pointed toward the benefits of using nasal cannula during emergency intubation.

Face mask leak with nasal cannula during noninvasive positive pressure ventilation: A randomized crossover trial

BACKGROUND

Nasal cannula can achieve apneic oxygenation during emergency intubation. However, pre-procedure nasal cannula placement may be difficult in patients undergoing non-invasive positive pressure ventilation (NPPV) prior to intubation. Our objective was to compare mask leak during NPPV with versus without simultaneous application of nasal cannula. We hypothesized mask leak would be no worse with concomitant use of nasal cannula (non-inferiority design).

METHODS

We performed a randomized crossover non-inferiority study of healthy volunteers. We randomized subjects undergoing 60s trials of NPPV (10cmH₂O continuous positive airway pressure) to either NPPV alone (NPPV-a) or NPPV with nasal cannula at 15L/min (NPPV-nc). After a brief rest period, all subjects underwent the alternative intervention. The primary outcome was time averaged mask leak over 60s (L/min). We defined a non-inferiority margin of 5L/min.

RESULTS

We enrolled 64 subjects. Mean time-averaged mask leak was 2.2L/min for NPPV-a versus 4.0L/min for NPPV-nc for a difference of 1.7L/min (one-sided 95% CI -∞ to 3.2L/min). NPPV-a resulted in higher mean minute volume received (13.5 versus 12.2L) and higher mean respiratory rates (14.8 versus 13.5 breaths per minute).

CONCLUSION

The addition of nasal cannula during NPPV does not significantly increase mask leak. The simultaneous application of nasal cannula with NPPV may be a useful strategy to streamline airway management among patients undergoing NPPV prior to intubation.

Emergency Department use of Apneic Oxygenation Versus Usual Care During Rapid Sequence Intubation: A Randomized Controlled Trial (The ENDAO Trial)

OBJECTIVES

Desaturation leading to hypoxemia may occur during rapid sequence intubation (RSI). Apneic oxygenation (AO) was developed to prevent the occurrence of oxygen desaturation during the apnea period. The purpose of this study was to determine if the application of AO increases the average lowest oxygen saturation during RSI when compared to usual care (UC) in the emergency setting.

METHODS

A randomized controlled trial was conducted at an academic, urban, Level I trauma center. All patients requiring intubation were included. Exclusion criteria were patients in cardiac or traumatic arrest or if preoxygenation was not performed. An observer, blinded to study outcomes and who was not involved in the procedure, recorded all times, while all saturations were recorded in real time by monitors on a secured server. Two-hundred patients were allocated to receive AO (n = 100) or UC (n = 100) by predetermined randomization in a 1:1 ratio.

RESULTS

A total of 206 patients were enrolled. There was no difference in lowest mean oxygen saturation between the two groups (92, 95% confidence interval [CI] = 91 to 93 in AO vs. 93, 95% CI = 92 to 94 in UC; p = 0.11).

CONCLUSION

There was no difference in lowest mean oxygen saturation between the two groups. The application of AO during RSI did not prevent desaturation of patients in this study population.

Apnoeic oxygenation during intubation in the intensive care unit: A systematic review and meta-analysis

Hypoxaemia increases the risk of cardiac arrest and mortality during intubation. The reduced physiological reserve and reduced efficacy of pre-oxygenation in intensive care patients makes their intubation particularly dangerous. Apnoeic oxygenation is a promising means of preventing hypoxaemia in this setting. We sought to ascertain whether apnoeic oxygenation reduces the incidence of hypoxaemia when used during endotracheal intubation in the intensive care unit (ICU). A systematic review of five databases for all relevant studies published up to November 2016 was performed. Eligible studies investigated apnoeic oxygenation during intubation in the ICU, irrespective of design. All studies were assessed for risk of bias and level of evidence. A meta-analysis was performed on all data using Revman 5.3. Six studies including 518 patients were retrieved. The study found level 1 evidence of a significant reduction in the incidence of critical desaturation (RR = 0.69, CI = 0.48-1.00, p = 0.05) and a significant increase in the lowest SpO2 value by 2.83% (CI = 2.28-3.38, p < 0.00001). There was a significant reduction in ICU stay (WMD = -2.89, 95%CI = -3.25 to -2.51, p < 0.00001). There was no significant difference between groups regarding mortality (RR = 0.77, 95%CI = 0.59-1.03, p = 0.08), first pass intubation success (RR = 1.17, 95%CI = 0.67 to 2.03, p = 0.58), arrhythmia during intubation (RR = 0.58, 95%CI = 0.08 to 4.29, p = 0.60), cardiac arrest during intubation (RR = 0.33, 95%CI = 0.01 to 7.84, p = 0.49) and duration of ventilation (WMD = -1.97, 95%CI = -5.89 to 1.95, p = 0.32). Apnoeic oxygenation reduces patient hypoxaemia during intubation performed in the ICU. This meta-analysis found evidence that apnoeic oxygenation may significantly reduce the incidence of critical desaturation and significantly raises the minimum recorded SpO2 in this setting. We recommend apnoeic oxygenation be incorporated into ICU intubation protocol.

Apnoeic oxygenation during intubation: a systematic review and meta-analysis

Apnoeic oxygenation during intubation is used to prevent desaturation during intubation. The aim of this review was to assess whether apnoeic oxygenation during endotracheal intubation reduced the incidence of hypoxaemia. Five major databases were systematically searched for all relevant studies published up to May 2016. All study designs with a control group and a group receiving apnoeic oxygenation were included in this review. These studies were then assessed for level of evidence and risk of bias. The data were then analysed using a meta-analysis. Eleven studies (six high quality randomised controlled trials, four low quality level two studies and one low quality level three study) were found. In the meta-analysis there was strong evidence for benefit of apnoeic oxygenation in terms of improved SpO₂ in elective surgical patients, obese patients and those undergoing emergency intubation without respiratory failure. However, no significant benefit was found in patients with respiratory failure. This is the first meta-analysis to be performed on apnoeic oxygenation during intubation. Apnoeic oxygenation provides significant benefit in terms of improving SpO₂ for the majority of intubations, although there appears to be no benefit in patients whose indication for intubation is respiratory failure. Apnoeic oxygenation ought to be considered for integration into intubation protocols.

Intubation using apnoeic oxygenation to prevent desaturation: A systematic review and meta-analysis

PURPOSE

To determine whether or not apnoeic oxygenation reduces the incidence of hypoxaemia during endotracheal intubation.

MATERIALS AND METHODS

A systematic search of six databases for all relevant studies until November 2016 was performed. All study designs using apnoeic oxygenation during intubation were eligible for inclusion. All studies were assessed for level of evidence and risk of bias. A meta-analysis was performed on all data using Revman 5.3.

RESULTS

Seventeen studies including 2422 patients were retrieved. Overall there was a significant reduction in the incidence of desaturation (RR=0.65; p<0.00001), critical desaturation (RR=0.61, p=0.002) and safe apnoea time (WMD=1.73min, p<0.00001). There was no significant difference in mortality (RR=0.77, p=0.08).

CONCLUSIONS

In patients whom are being intubated for any indication other than respiratory failure, apnoeic oxygenation at any flow rate 15L or greater is likely to reduce their incidence of desaturation (<90%) and critical desaturation (<80%). However, further high quality RCTs are required given the high degree of heterogeneity in many of the outcomes and subgroup analyses.

Republication: All India Difficult Airway Association 2016 Guidelines for Tracheal Intubation in the Intensive Care Unit

Tracheal intubation (TI) is a routine procedure in the Intensive Care Unit (ICU) and is often lifesaving. In contrast to the controlled conditions in the operating room, critically ill patients with respiratory failure and shock are physiologically unstable. These factors, along with under evaluation of the airway and suboptimal response to preoxygenation, are responsible for a high incidence of life-threatening complications such as severe hypoxemia and cardiovascular collapse during TI in the ICU. The All India Difficult Airway Association (AIDAA) proposes a stepwise plan for safe management of the airway in critically ill patients. These guidelines have been developed based on available evidence; Wherever, robust evidence was lacking, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the (AIDAA) and Indian Society of Anaesthesiologists. Noninvasive positive pressure ventilation for preoxygenation provides adequate oxygen stores during TI for patients with respiratory pathology. Nasal insufflation of oxygen at 15 L/min can increase the duration of apnea before hypoxemia sets in. High flow nasal cannula oxygenation at 60-70 L/min may also increase safety during intubation of critically ill patients. Stable hemodynamics and gas exchange must be maintained during rapid sequence induction. It is necessary to implement an intubation protocol during routine airway management in the ICU. Adherence to a plan for difficult airway management incorporating the use of intubation aids and airway rescue devices and strategies is useful.

The All India Difficult Airway Association 2016 guidelines for tracheal intubation in the Intensive Care Unit

Tracheal intubation (TI) is a routine procedure in the Intensive Care Unit (ICU) and is often life-saving. In contrast to the controlled conditions in the operating room, critically ill patients with respiratory failure and shock are physiologically unstable. These factors, along with a suboptimal evaluation of the airway and limited oxygen reserves despite adequate pre-oxygenation, are responsible for a high incidence of life-threatening complications such as severe hypoxaemia and cardiovascular collapse during TI in the ICU. The All India Difficult Airway Association (AIDAA) proposes a stepwise plan for safe management of the airway in critically ill patients. These guidelines have been developed based on available evidence; wherever robust evidence was lacking, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the AIDAA and the Indian Society of Anaesthesiologists. Non-invasive positive pressure ventilation during pre-oxygenation improves oxygen stores in patients with respiratory pathology. Nasal insufflation of oxygen at 15 L/min can increase the duration of apnoea before the occurrence of hypoxaemia. High-flow nasal cannula oxygenation at 60-70 L/min may also increase safety during TI in critically ill patients. Stable haemodynamics and gas exchange must be maintained during rapid sequence induction. It is necessary to implement an intubation protocol during routine airway management in the ICU. Adherence to a plan for difficult airway management incorporating the use of intubation aids and airway rescue devices and strategies is useful.