Out-of-hospital tracheal intubation with single-use versus reusable metal laryngoscope blades: a multicenter randomized controlled trial

Predictive and protective factors for failing first pass intubation in prehospital rapid sequence intubation: an aetiology and risk systematic review with meta-analysis

BACKGROUND

Prehospital rapid sequence intubation first pass success rates vary between 59% and 98%. Patient morbidity is associated with repeat intubation attempts. Understanding what influences first pass success can guide improvements in practice. We performed an aetiology and risk systematic review to answer the research question 'what factors are associated with success or failure at first attempt laryngoscopy in prehospital rapid sequence intubation?'.

METHODS

MEDLINE, EMBASE, CINAHL, and Cochrane Library were searched on March 3, 2023 for studies examining first pass success rates for rapid sequence intubation of prehospital live patients. Screening was performed via Covidence, and data synthesised by meta-analysis. The review was registered with PROSPERO and performed and reported as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Reasonable evidence was discovered for predictive and protective factors for failure of first pass intubation. Predictive factors included age younger than 1 yr, the presence of blood or fluid in the airway, restricted jaw or neck movement, trauma patients, nighttime procedures, chronic or acute distortions of normal face/upper airway anatomy, and equipment issues. Protective factors included an experienced intubator, adequate training, use of certain videolaryngoscopes, elevating the patient on a stretcher in an inclined position, use of a bougie, and laryngeal manoeuvres.

CONCLUSIONS

Managing bloody airways, positioning well, using videolaryngoscopes with bougies, and appropriate training should be further explored as opportunities for prehospital services to increase first pass success. Heterogeneity of studies limits stronger conclusions.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42022353609).

Single-use versus reusable metallic laryngoscopes for non-emergent intubation: A retrospective review of 72,672 intubations

STUDY OBJECTIVE

Increased regulatory requirements for sterilization in recent years have prompted a widespread transition from reusable to single-use laryngoscopes. The purpose of this study was to determine if the transition from metallic reusable to metallic single-use laryngoscopes impacted the performance of direct laryngoscopy at an academic medical center.

DESIGN

Single-site retrospective cohort study.

SETTING

General anesthetic cases requiring tracheal intubation.

PATIENTS

Adult patients undergoing non-emergent procedures.

INTERVENTIONS

Data were collected two years before and two years after a transition from metallic reusable to metallic single-use laryngoscopes.

MEASUREMENTS

The primary outcome was need for intubation rescue with an alternate device. Secondary outcomes were difficult laryngeal view (modified Cormack-Lehane grade ≥ 2b) and hypoxemia (SpO2 < 90% for >30 s) during direct laryngoscopy intubations. Subgroup analyses for rapid sequence induction, Macintosh blades, Miller blades, and patients with difficult airway risk factors (Obstructive Sleep Apnea, Mallampati ≥3, Body Mass Index >30 kg/m2) were performed.

MAIN RESULTS

In total, 72,672 patients were included: 35,549 (48.9%) in the reusable laryngoscope cohort and 37,123 (51.1%) in the single-use laryngoscope cohort. Compared with reusable laryngoscopes, single-use laryngoscopes were associated with fewer rescue intubations with an alternate device (covariates-adjusted odds ratio [OR] 0.81 95% CI 0.66-0.99). Single-use laryngoscopes were also associated with lower odds of difficult laryngeal view (OR 0.86; 95% CI 0.80-0.93). Single use laryngoscopes were not associated with hypoxemia during the intubation attempt (OR 1.03; 95% CI 0.88-1.20). Similar results were observed for subgroup analyses including rapid sequence induction, Macintosh blades, Miller blades, and patients with difficult airway risk factors.

CONCLUSIONS

Metallic single-use laryngoscopes were associated with less need for rescue intubation with alternate devices and lower incidence of poor laryngeal view compared to reusable metallic laryngoscopes.

Factors associated with tracheal intubation-related complications in the prehospital setting: a prospective multicentric cohort study

Background Emergency tracheal intubation is routinely performed in the prehospital setting. Airway management in the prehospital setting has substantial challenges. Objective The aim of the present study was to determine risk factors predicting tracheal intubation-related complications on the prehospital field. Setting A prospective, multicentric, cohort study which was conducted in three mobile ICUs (MICUs; service mobile d'urgence et de réanimation).Outcome measures and analysis Tracheal intubation-related complications were defined as the occurrence of at least one of the following events: oxygen desaturation (SpO2 < 90%) during tracheal intubation, aspiration (regurgitation visualized during laryngoscopy), and vomiting. Difficult intubation was defined as more than two failed direct laryngoscopic attempts, or the need for any alternative tracheal intubation method. Multivariate logistic regressions were used. Results During the 5-year study period, 1915 consecutive patients were intubated in the MICUs participating in the study. Overall, 1287 (70%) patients were successfully intubated after the first laryngoscopic attempt, with rates of 90, 74, 42, and 30% for Cormack-Lehane grade 1, 2, 3, and 4, respectively. Tracheal intubation was difficult in 663 cases (36%). Tracheal intubation-related complications occurred in 267 (14%) patients. In the multivariate analysis, we found that the leading risk factors for tracheal intubation-related complications were Cormack and Lehane grade 3 and 4 [odds ratio (OR) = 1.65; 95% confidence interval (CI), 1.05-2.61; and OR = 2.79; 95% CI, 1.56-4.98, respectively], a BMI of more than 30 (OR = 1.61; 95% CI, 1.13-2.28), when intubation was difficult (OR = 1.72; 95% CI, 1.15-2.57), and when tracheal intubation required more than one operator (OR = 2.30; 95% CI, 1.50-3.49).Conclusions In this prospective study, we found that Cormack and Lehane more than grade 2, BMI >30, difficult intubation, and tracheal intubation requiring more than one operator were all independent predictors of tracheal intubation-related complications in the prehospital setting. When these risk factors are identified on scene, adapted algorithms that anticipate the use of a bougie should be generalized to reduce morbidity on the prehospital field.

Association between First-pass Intubation Success and Enhanced PPE Use during the COVID-19 Pandemic

OBJECTIVES

We evaluated first-pass endotracheal intubation (ETI) success within the critical care transport (CCT) environment using a natural experiment created by the COVID-19 pandemic. Our primary objective was to evaluate if the use of personal protective equipment (PPE) or the COVID-19 time period was associated with differences in first-pass success rates of ETI within a large CCT system with a high baseline ETI first-pass success rate. We hypothesized that pandemic-related challenges would be associated with decreased first-pass success rates.

METHODS

We performed a retrospective before-after cohort study of airway management by CCT personnel relative to the COVID-19 pandemic. We used a mixed effects logistic regression to evaluate the association between enhanced PPE (N95 mask, eye protection) use and the pandemic time period on first-pass intubation success, while controlling for other factors potentially associated with intubation success. Variables in the final model included patient demographics (age, sex, and race), body mass index, medical category (trauma versus non-trauma), interfacility or scene response, blade size (Macintosh 3 versus 4), use of face mask, use of eye protection, and crew member length of service.

RESULTS

We identified 1279 cases involving intubation attempts on adult patients during the study period. A total of 1133 cases were included in the final analysis, with an overall first-pass success rate of 95.7% (96.4% pre-COVID-19 and 94.8% during COVID-19). In our final mixed effects logistic regression model, enhanced PPE use and the COVID-19 time period were not associated with first-pass intubation success rate.

CONCLUSION

In a large regional CCT system with a high ETI first-pass success rate, neither PPE use nor the COVID-19 time period were associated with differences in ETI first-pass success while controlling for relevant patient and operational factors. Other emergency medical services (EMS) systems may have encountered different effects of pandemic-related PPE use on intubation success rates. Further studies are needed to evaluate the influence of sustained use of enhanced PPE or changes in training or procedural experience on post-pandemic ETI first-pass success rates for non-CCT EMS clinicians.

Disposable laryngoscope intubation to reduce equipment failure in an emergency out of OR setting - a quality control case study

BACKGROUND

Reusable laryngoscopes have been reported to be superior to disposable laryngoscopes with plastic blades during emergent intubations. Surprisingly, at our institution a quality reporting system revealed a high number of equipment failures with reusable laryngoscopes in an emergency out-of-OR (operating room) setting. As recent studies indicated an improved quality of disposable laryngoscopes, we hypothesized that a thoroughly evaluated disposable laryngoscope would result in less equipment failure in an emergency out-of-OR setting.

METHODS

To perform a more standardized and time efficient analysis, four distinct disposable laryngoscope blade/handle configurations were trialed during standard intubations (n = 4 × 30) in the OR by experienced anesthesia providers who completed a 6-question, Likert-scale/open-ended survey for product evaluation. The 'best' disposable blade was implemented in an emergency out-of-OR setting and equipment failure rates were monitored over a 3-year period.

RESULTS

Different disposable laryngoscopes were equal regarding sturdiness, illumination and airway visualization. The laryngoscope with the highest overall score was significantly higher scored than the laryngoscope with the lowest overall score. All disposable laryngoscopes were more cost effective than the reusable ones, and the top scored laryngoscope demonstrated the highest 5-year cost-saving ($210 K). Implementation of the top scored disposable laryngoscope into an emergency out-of-OR setting reduced the equipment failure incidence from high 20s to 0.

CONCLUSION

Disposable laryngoscopes are cost effective and superior to reusable laryngoscopes in an emergency out-of-OR setting. We demonstrate that the implementation of a disposable laryngoscope in the emergency out-of-OR setting resulted in a near elimination of equipment related quality submissions which ultimately enhances patient safety.

Peripheral tissue hypoperfusion predicts post intubation hemodynamic instability

Background

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

Methods

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

Results

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

Conclusions

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

Supplementary Information

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

Le mandrin long béquillé : est-ce systématique ?

L’intubation trachéale (IT) est un geste fréquent en médecine d’urgence extra-hospitalière (MUEH) mais elle est associée à un taux élevé d’échec de la première tentative et à certaines complications graves. Le taux de ces dernières augmente avec le nombre de tentative d’IT. La Société française d’anesthésie et de réanimation (SFAR) et la Société de réanimation de langue française (SRLF) avec la collaboration de la Société française de médecine d’urgence (SFMU) ont publié en 2016 des recommandations formalisées d’experts (RFE) sur l’intubation du patient de réanimation. La question qui se pose est la pertinence de ces recommandations pour la MUEH. En effet, la mesure du risque de difficulté est basée sur le score de MACOCHA et en cas de difficulté prévue les outils à utiliser d’emblée sont le vidéo-laryngoscope ou le mandrin long béquillé en laryngoscopie directe. Or il apparait que le score de MACOCHA n’est pas adapté à la MUEH et de façon plus générale, il est complexe de mesurer le risque d’intubation difficile (ID) dans ce contexte. La vidéolaryngoscopie n’a pas encore fait la preuve de sa supériorité par rapport à la laryngoscopie directe en MUEH. Par contre des travaux récents en médecine d’urgence ont démontré que l’utilisation en première intention du mandrin long béquillé augmente significativement le taux de succès de la première tentative de l’IT, même en l’absence de facteur de risque d’ID. Au total, on pourrait considérer chaque IT en MUEH comme a priori à risque de difficulté ce qui justifierait une utilisation d’emblée du mandrin long béquillé. Il semble nécessaire de proposer des recommandations spécifiques à la médecine d’urgence.

Incidence, Complications, and Factors Associated with Out-of-Hospital First Attempt Intubation Failure in Adult Patients: A Secondary Analysis of the CURASMUR Trial Data

Objectives: The objectives of this study were to evaluate first attempt intubation failure rate, its associated factors, and its related complications in out-of-hospital emergency setting, when emergency physicians perform standardized airway management using rapid sequence intubation in adult patients. Material and methods: The present study was a substudy of the Succinylcholine versus Rocuronium for out-of-hospital Emergency Intubation (CURASMUR) Trial, which compared Succinylcholine and Rocuronium used for Rapid sequence intubation. First attempt Intubation failure rate and early intubation related complications were recorded. We used multivariable logistic regression analysis to determine first intubation failure associated factors. Results: A total of 1230 patients were included with mean age of 55.9 +/- 19 years. First attempt intubation failure was recorded in 285 (23.2%) patients. The occurrence of a first attempt intubation failure was independently associated with history of ear, nose, and throat neoplasia (OR 2.20, CI 95% 1.06-4.60). Early intubation related complications were more frequent in case of first attempt intubation failure: 80 of 285 (28.4%) in patients with first attempt intubation failure and 185 of 945 (19.6%) in patients with successful first attempt intubation [OR 1.44; CI 95%, 1.11-1.87]. Conclusion: Based on a large multicenter study on out-of-hospital tracheal intubation of adult patients, we found that first attempt intubation failure rate was high and that history of ear, nose, and throat (ENT) neoplasia was an independent associated factor. Failure in first intubation attempt was associated with significantly more intubation related complications.

Effect of Rocuronium vs Succinylcholine on Endotracheal Intubation Success Rate Among Patients Undergoing Out-of-Hospital Rapid Sequence Intubation: A Randomized Clinical Trial

IMPORTANCE

Rocuronium and succinylcholine are often used for rapid sequence intubation, although the comparative efficacy of these paralytic agents for achieving successful intubation in an emergency setting has not been evaluated in clinical trials. Succinylcholine use has been associated with several adverse events not reported with rocuronium.

OBJECTIVE

To assess the noninferiority of rocuronium vs succinylcholine for tracheal intubation in out-of-hospital emergency situations.

DESIGN, SETTING AND PARTICIPANTS

Multicenter, single-blind, noninferiority randomized clinical trial comparing rocuronium (1.2 mg/kg) with succinylcholine (1 mg/kg) for rapid sequence intubation in 1248 adult patients needing out-of-hospital tracheal intubation. Enrollment occurred from January 2014 to August 2016 in 17 French out-of-hospital emergency medical units. The date of final follow-up was August 31, 2016.

INTERVENTIONS

Patients were randomly assigned to undergo tracheal intubation facilitated by rocuronium (n = 624) or succinylcholine (n = 624).

MAIN OUTCOMES AND MEASURES

The primary outcome was the intubation success rate on first attempt. A noninferiority margin of 7% was chosen. A per-protocol analysis was prespecified as the primary analysis.

RESULTS

Among 1248 patients who were randomized (mean age, 56 years; 501 [40.1%] women), 1230 (98.6%) completed the trial and 1226 (98.2%) were included in the per-protocol analysis. The number of patients with successful first-attempt intubation was 455 of 610 (74.6%) in the rocuronium group vs 489 of 616 (79.4%) in the succinylcholine group, with a between-group difference of -4.8% (1-sided 97.5% CI, -9% to ∞), which did not meet criteria for noninferiority. The most common intubation-related adverse events were hypoxemia (55 of 610 patients [9.0%]) and hypotension (39 of 610 patients [6.4%]) in the rocuronium group and hypoxemia (61 of 616 [9.9%]) and hypotension (62 of 616 patients [10.1%]) in the succinylcholine group.

CONCLUSIONS AND RELEVANCE

Among patients undergoing endotracheal intubation in an out-of-hospital emergency setting, rocuronium, compared with succinylcholine, failed to demonstrate noninferiority with regard to first-attempt intubation success rate.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02000674.

Tracheal intubation related complications in the prehospital setting

BACKGROUND

Prehospital tracheal intubation (TI) is associated with morbidity and mortality, particularly in cases of difficult intubation. The goal of the present study was to describe factors associated with TI related complications in the prehospital setting.

METHODS

This was a prospective cohort study including all patients intubated on scene in a prehospital emergency medical service over a 4 year period. TI related complications included oxygen desaturation, aspiration, vomiting, bronchospasm and/or laryngospasm, and mechanical complications (mainstem intubation, oesophageal intubation and airway lesion- that is, dental or laryngeal trauma caused by the laryngoscope). Difficult intubation was defined as >2 failed laryngoscopic attempts, or the need for any alternative TI method. A multivariate logistic regression was used to identify the risk factors for TI related complications.

RESULTS

1251 patients were included; 208 complications occurred in 165 patients (13.1%). Among the 208 complications, the most frequent were oesophageal intubation (n=69, 29.7%), desaturation (n=58, 25.0%) and mainstem intubation (n=37, 15.9%). In multivariate analysis, difficult intubation (OR=6.13, 3.93 to 9.54), Cormack and Lehane grades 3 and 4 (OR=2.23, 1.26 to 3.96 for Cormack and Lehane grade 3 and OR=2.61, 1.28 to 5.33 for Cormack and Lehane grade 4 compared with Cormack and Lehane grade 1) and a body mass index >30 kg/m(2) (OR=2.22, 1.38 to 3.56) were significantly associated with TI related complications.

CONCLUSIONS

Despite specific guidelines, TI related complications are more frequent in the prehospital setting when intubation is deemed difficult, the Cormack and Lehane grade is greater than grade 1 and the patient is overweight. In such situations, particular attention is needed to avoid complications.

The process of prehospital airway management: challenges and solutions during paramedic endotracheal intubation

OBJECTIVES

Endotracheal intubation success rates in the prehospital setting are variable. Our objective was to describe the challenges encountered and corrective actions taken during the process of endotracheal intubation by paramedics.

DESIGN

Analysis of prehospital airway management using a prospective registry that was linked to an emergency medical services administrative database.

SETTING

Emergency medical services system serving King County, Washington, 2006-2011. Paramedics in this system have the capability to administer neuromuscular blocking agents to facilitate intubation (i.e., rapid sequence intubation).

PATIENTS

A total of 7,523 patients more than 12 years old in whom paramedics attempted prehospital endotracheal intubation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

An intubation attempt was defined as the introduction of the laryngoscope into the patient's mouth, and the attempt concluded when the laryngoscope was removed from the mouth. Endotracheal intubation was successful on the first attempt in 77% and ultimately successful in 99% of patients (7,433 of 7,523). Paramedics used a rapid sequence intubation strategy on 54% of first attempts. Among the subset with a failed first attempt (n = 1,715), bodily fluids obstructing the laryngeal view (50%), obesity (28%), patient positioning (17%), and facial or spinal trauma (6%) were identified as challenges to intubation. A variety of adjustments were made to achieve intubation success, including upper airway suctioning (used in 43% of attempts resulting in success), patient repositioning (38%), rescue bougie use (19%), operator change (16%), and rescue rapid sequence intubation (6%). Surgical cricothyrotomy (0.4%, n = 27) and bag-valve-mask ventilation (0.8%, n = 60) were rarely performed by paramedics as final rescue airway strategies.

CONCLUSIONS

Airway management in the prehospital setting has substantial challenges. Success can require a collection of adjustments that involve equipment, personnel, and medication often in a simultaneous fashion.