Clinical Characteristics of Patients Undergoing Needle Thoracostomy in a Canadian Helicopter Emergency Medical Service

Abstract

Objective: Needle thoracostomy (NT) can be a life-saving procedure when used to treat tension pneumothorax. However, there is some question regarding the efficacy of NT in the prehospital setting. Failure to treat tension pneumothorax in a helicopter emergency medical service (HEMS) setting may prove especially deleterious to the patient due to gas expansion with increasing altitude. This study's objective was to identify the characteristics of patients treated with NT in a Canadian HEMS setting and the factors that may influence outcomes following NT use. Methods: This was a retrospective chart review of prehospital records from a Canadian HEMS service. Patients aged 18 years and older who underwent at least one NT attempt using a 14-gauge 8.3 cm needle from 2012 to 2018 were identified. Charts were reviewed to collect demographic data, NT procedural characteristics, vital signs, and clinical response metrics. Descriptive statistics were used to characterize the study sample and overall event characteristics. Binary logistic regression was performed to identify variables associated with a clinical response to the initial NT treatment. Results: 163 patients (1.3%) of 12,407 patients attended received NT. A positive clinical response to NT was recorded in 37% (n = 77) of the total events (n = 208), the most common of which was an improvement in blood pressure (BP) (18.8%, n = 39). Initial NT was associated with a low likelihood of clinical improvement in patients presenting with blunt trauma (OR = 0.18; p = .021; 95% CI [.04, .77]), CPR prior to NT (OR = 0.14; p = .02; 95% CI [.03, .73]), or in those who received bilateral NT treatment (OR = 0.13; p < .01; 95% CI [.05, .37]). A pretreatment BP < 90 mmHg was predictive of a positive clinical response to initial NT (OR = 3.33; p = .04; 95% CI [1.09, 10.20]). Conclusions: Only a small portion of patients in the setting of a Canadian HEMS service were treated with NT. Patients most likely to receive NT were males who had suffered blunt trauma. NT may have questionable benefit for patients presenting with blunt trauma, in cardiac arrest, or requiring bilateral NT.