Henry E.Wang, Robert H. Schmicker, Mohamud R. Daya et el published PART trial (Pragmatic Airway Resuscitation
Trial) in which they compared laryngeal tube insertion with endotracheal intubation in out of hospital cardiac arrest.
About 350000 adults in the United States suffer out of hospital cardiac arrest each year, with less than 10%surviving to hospital discharge. More than 30 years ago, Endotracheal intubation became a standard US paramedic practice under the assumption that it would improve OHCA outcomes. However, many studies have highlighted the challenges of paramedic Endotracheal intubation , including significant rates of unrecognized tube misplacement
or dislodgement, need for multiple attempts, and insertion failure. Endotracheal intubation been associated
with iatrogenic hyperventilation and chest compression interruptions. Last but not least, paramedics may only perform 1 live intubation per year.
Supraglottic airway (SGA) devices include the laryngeal mask airway, esophageal-tracheal combitube, i-gel, and laryngeal tube (LT). Compared with endotracheal intubation, SGA insertion is rapid, simple, and requires less training.
Adults 18 yrs or older with non traumatic out of hospital cardiac arrest. Total of 3004 patients.
Following were excluded– pregnancy, prisoners, ET tube before EMS arrival, tracheostomy presence, DNR orders.
Multicenter pragmatic cluster-crossover clinical trial, funded by a National Heart, Lung, and Blood
Institute (NHLBI) involving 31 EMS agencies from following states- Alabama, Texas, Wisconsin, Pennsylvania, Oregon and Washington.
Primary outcome was survival to 72 hours.
Secondary trial outcomes included (1) ROSC(presence of palpable pulses on emergency department arrival), (2) survival to hospital discharge, and (3) favorable neurological status on hospital discharge (Modified Rankin Scale score ≤3). Other secondary outcomes included EMS airway management course and hospital adverse events.
72-hour survival was 18.3% in the Laryngeal tube group vs 15.4% in the Endotracheal intubation group. ( difference was 2.9% (95% CI, 0.2%-5.6%; P = .04; relative risk, 1.19 [95% CI, 1.01-1.39])
Laryngeal tube vs Endotracheal intubation
- Return of spontaneous circulation (27.9% vs 24.3%; adjusted difference, 3.6% [95% CI, 0.3%-6.8%]; P = .03)
- Hospital survival (10.8% vs 8.1%; adjusted difference, 2.7% [95% CI, 0.6%-4.8%; P = .01)
- Favorable neurological status at discharge (7.1% vs 5.0%; adjusted difference, 2.1% [95% CI, 0.3%-3.8%] P = .02).
BASELINE CHARACTERISTICS DIFFERENCES
Following differences were observed between two groups
- Elapsed time from first EMS arrival to airway start was shorter for LT than ETI (median, 9.8 vs 12.5 minutes).
- Initial LT and ETI success rates (excluding BVM) were 90.3% and 51.6%.
- Clinicians at receiving emergency departments converted 64.4% of EMS LT to ETI.
- Among patients receiving successful EMS ETI, emergency department clinicians performed repeat ETI in 33.1%.
- A total of 352 patients received BVM only without any advanced airway insertion efforts.
LIMITATIONS OF STUDY
- In Pragmatic trials , Power is decreased and a larger sample size is needed compared with an individual randomized trial.
- Trial could not assess the influence of chest compression or ventilation quality.
- Trial focused on LT use and not other SGAs