Disclaimer: The views and opinions presented in the following article do not represent those of my employer or any partner affiliate. They are mine alone.
Rural and remote settings can offer Paramedic practitioners some of the most challenging experiences over their urban counter parts. Perhaps one the most stressful challenges a practitioner will encounter in this realm is the difficult airway – in the middle of a pandemic.
It perhaps stands to reason, that given the setting and the current global crisis practitioners should have the best tools possible at their disposal. The is especially true of endotracheal intubation as noted by Savino et al. (2017) by noting the “ability to perform oral endotracheal intubation safely and effectively is of paramount importance to the health of the patient in the prehospital setting” . It is understood that medical directives and protocols sanctioning prehospital intubation vary widely, for example some Canadian jurisdictions allow for Rapid Sequence Induction and Paralysis or RSIP; this is best described by rapid endotracheal intubation after induction and paralysis in which both unconsciousness and neuromuscular blockage occur . The most common indications for endotracheal intubation remain respiratory and cardiac arrest .
There are many predictors to a difficult airway which will certainly lead to a difficult endotracheal intubation, these predictors may include but are not limited to: limited access to the patient and biophysical conditions such as obesity, short neck, facial and/or neck injuries as well as anatomical restrictions . As defined in the “Practical guidelines for management of difficult airways” by the American Society of Anesthesiologists, difficult endotracheal intubation is more than one attempt needed to successfully perform endotracheal intubation .
Prehospital studies of endotracheal intubation have used overall procedure (intubation) success as the primary outcome, however the single most important bench mark to pay attention to is ‘first-pass success’ and is defined as successful intubation on the first attempt . This bench mark has become, “recognized as an important outcome measure as studies have shown an increase in adverse event rate with successive failed attempts . Many studies have examined the association between the type of practitioner performing endotracheal intubation and its success rate. These studies have typically shown that, Paramedics tend to have lower first-pass success rates than Physicians, said to be 46% to 77% compared with 71% to 88% for Physicians outside of the hospital and 61% to 97% for Physicians performing in-hospital endotracheal intubation . Now, arguably there can be many reasons for the large gap in percentages. This can include practitioner education, experience, equipment and difficulty level of the airway. This seems to be echoed by the work of Rhodes et al. (2016) where it was noted that, “PHETI first-pass success rates differ hugely between different pre-hospital emergency medical systems (EMS) and seem to be highly influenced by the organisation, staffing, case load and case mix of the EMS studied” . Additionally, rates of complication appear to be correlated to repeated pre-hospital endotracheal intubation, while both difficult and failed endotracheal intubation have been associated with an increase in morbidity and mortality .
Historically, the standard approach for intubation regardless of setting had been direct laryngoscopy or DL. This method requires a direct line of sight between the practitioner’s eyes and the vocal cords in order to place the endotracheal tube. In contrast, the approach of using video technology employs a device that, “indirectly views the vocal cords by way of fiber optics, video cameras, mirrors or other methods”  which project an image of the patient’s airway onto a screen, which is viewed in real time by the practitioner as the endotracheal tube is being placed.
In today’s world – pandemic and all, the use of rigid video laryngoscopy is now being advocated for by many practitioners in the management of the difficult airway and why not? Previous studies have demonstrated that the use of video laryngoscopes greatly improve laryngeal view and ease intubation difficulty . Aziz et al. (2012) also noted studies had, “further established that laryngeal view is improved compared with direct laryngoscopy across various airway scenarios” , and in particular novice practitioners demonstrated an improved success rates with video laryngoscopy as compared with direct laryngoscopy in the management of a routine airway . The work of Silverberg et al. (2015) remarked that video laryngoscopy, “showed improved glottic view and first-attempt success compared with direct laryngoscopes in nonparalyzed patients” .
So, the good news is that in recent years video laryngoscopy has gained popularity and with good reason, in Savino et al. (2017), where they highlighted the use of direct laryngoscopy in the emergency department setting had declined from 95% in 2002 to approximately 55% in 2012, along with a concomitant increase in video laryngoscopy, from less than 5% to 39% . Furthermore, in a meta-analysis conducted by Savino et al. (2017) examined first-pass success rates and the rates of difficult intubation with direct laryngoscopy compared to video devices in the hospital setting – chiefly in the operating room and in intensive care units, suggest that video laryngoscopy is associated with a high first-pass success rate accompanied by a decrease in the rate of difficult endotracheal intubation, most notably among novice practitioners .
What does that mean for the rural and/or remote Paramedic? Video laryngoscopy definitely has the potential to facilitate and improve first-pass success with respect to pre-hospital endotracheal intubation , . However, the pre-hospital use of video laryngoscopy has not been broadly studied. Additionally, Rhode et al. (2016) note that, “only a few reports exist on the use of VL to sure the airway in the pre-hospital setting” . And it is perhaps for this reason, in addition to cost that some rural and remote settings will not move towards a safer and more efficient way of managing difficult airways, thus putting patients and practitioners at risk. In an era where aerosol generating procedures should be kept to a minimum it would irresponsible to not provide practitioners with the available technology that would aid in the reduction of morbidity and mortality. If cost remains as the only constraint, let’s be honest as a system we have spent more money on less.
- Savino P, Reichelderfer S, Mercer M, Wang R, Sporer K. Direct Versus Video Laryngoscopy for Prehospital Intubation: A Systematic Review and Meta-analysis. Academic Emergency Medicine. 2017;24(8):1018-1026.
- Alberta Health Services EMS, n.d. Critical Care Medical Control Protocols (V2.3).
- Rhode M, Vandborg M, Bladt V, Rognås L. Video laryngoscopy in pre-hospital critical care – a quality improvement study. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. 2016;24(1).
- Aziz M, Dillman D, Fu R, Brambrink A. Comparative Effectiveness of the C-MAC Video Laryngoscope versus Direct Laryngoscopy in the Setting of the Predicted Difficult Airway. Anesthesiology. 2012;116(3):629-636.
- Silverberg M, Li N, Acquah S, Kory P. Comparison of Video Laryngoscopy Versus Direct Laryngoscopy During Urgent Endotracheal Intubation. Critical Care Medicine. 2015;43(3):636-641.
- Lewis S, Butler A, Parker J, Cook T, Smith A. Videolaryngoscopy versus direct laryngoscopy for adult patients requiring tracheal intubation. Cochrane Database of Systematic Reviews. 2016.