The impact of video laryngoscopy on the first-pass success rate of prehospital endotracheal intubation in The Netherlands: a retrospective observational study

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).

Using a Bougie With C-MAC Video Laryngoscopy Did Not Improve First-Attempt Intubation Success Rates in Critical Care Air Transport

OBJECTIVE

Studies have shown a bougie improves first-attempt success rates when used in combination with direct laryngoscopy during the initial attempt. The purpose of this study was to determine whether the use of a bougie in combination with C-MAC (Karl Storz, Tuttlingen, Germany) improves first-attempt success rates of endotracheal intubation (ETI) compared with C-MAC with a traditional stylet.

METHODS

This study is a retrospective chart review using data collected on 371 intubations completed by a single air medical service using the C-MAC laryngoscope and either a bougie or a stylet.

RESULTS

The overall success rate using C-MAC for ETI with either a bougie or a stylet was 83%. There was no statistically significant difference between first-attempt successful intubations using C-MAC and a bougie (82%) or a stylet (86%) (χ1 = 0.871, P = .351). There was no statistically significant difference between laryngoscopy grade and the number of attempts that resulted in a successful intubation (χ1 = 0.743, P = .7).

CONCLUSION

There was no difference between first-attempt success rates using video laryngoscopy with a bougie, overall intubation success rates, or difficult intubation success rates compared with video laryngoscopy with a stylet, indicating that the purpose of a bougie as a rescue device did not hold true in the prehospital setting of our critical care air medical service.

Video Laryngoscopy versus Direct Laryngoscopy for Orotracheal Intubation in the Out-of-Hospital Environment: A Systematic Review and Meta-Analysis

OBJECTIVE

To determine the effect of video and direct laryngoscopy on first-pass success rates for out-of-hospital orotracheal intubation.

METHODS

MEDLINE, Embase, and Cochrane databases were searched from inception to January 2023. Out-of-hospital studies comparing video and direct laryngoscopy on either first-pass or overall intubation success were included. A random effects meta-analysis was performed with a primary outcome of first-pass success stratified by clinician type and laryngoscope blade geometry. The secondary outcomes were overall intubation success stratified by clinician type, and intubation time. All hypotheses and subgroup analyses were determined a priori.

RESULTS

Twenty-five studies involving 35,489 intubations met inclusion criteria. Substantial heterogeneity (>75%) precluded reporting point estimates for nearly all analyses. For our primary outcome, video laryngoscopy was associated with improved first-pass success in 3/5 physician studies, 4/6 critical care paramedic/registered nurse studies, and 7/10 paramedic studies. Video laryngoscope devices with Macintosh blade geometry were associated with improved first-pass success in 7/10 studies, while devices with hyperangulated geometry were associated with improved first-pass success in 3/7 studies. Overall intubation success was greater with video laryngoscopy in 2/6 studies in the physician subgroup and 9/10 studies in the paramedic subgroup. Video laryngoscopy was not associated with overall intubation success among critical care paramedics/nurses (OR = 1.89, 0.96 to 3.72, I2 = 34%). Lastly, 4/5 studies found video laryngoscopy to be associated with longer intubation times.

CONCLUSIONS

We found substantial heterogeneity among out-of-hospital studies comparing video laryngoscopy to direct laryngoscopy on first-pass success, overall success, or intubation time. This heterogeneity was not explained with stratification by study design, clinician type, video laryngoscope blade geometry, or leave-one-out meta-analysis. A majority of studies showed that video laryngoscopy was associated with improved first pass success in all subgroups, but only for paramedics and not physicians when looking at overall success. This improvement was more common in studies that used Macintosh blades than those that used hyperangulated blades. Future research should explore the heterogeneity identified in our analysis with an emphasis on differences in training, clinical milieu, and specific video laryngoscope devices.

Video versus direct laryngoscopy by specialist paramedics in New South Wales: Preliminary results from a new airway registry

OBJECTIVES

Video laryngoscopy (VL) is increasingly used as an alternative to direct laryngoscopy (DL) to improve airway visualisation and endotracheal intubation (ETI) success. Intensive Care Paramedics in New South Wales Ambulance, Australia started using VL in 2020, and recorded success in a new advanced airway registry. We used this registry to compare VL to DL.

METHODS

The present study was a retrospective analysis of out-of-hospital data for ETI by specialist paramedics using an airway registry. We calculated overall and first-pass success for VL versus DL, and compared success using a Χ² test.

RESULTS

The DL overall success was 61 out of 78 (78.2%) and VL was 233 out of 246 (94.7%); difference of 16.5% (P < 0.001). First-pass for DL was successful for 49 out of 78 (62.8%) and for VL in 195 out of 246 (79.3%); difference of 16.5% (P = 0.003). There were five (1.6%) patients where both VL and DL were used and in all instances, DL was used first.

CONCLUSIONS

This analysis of a new airway registry used by specialist paramedics in New South Wales shows a substantial increase in overall and first-pass intubation success with the use of VL when compared to DL.