Association Between Train-of-Four Values and Gas Exchange Indices in Moderate to Severe Acute Respiratory Distress Syndrome.

Abstract

Acute respiratory distress syndrome (ARDS) is associated with a mortality rate of approximately 40%. Neuromuscular blockade is associated with an improvement in oxygenation and a reduction in mortality in ARDS. The goal of this evaluation was to determine if the depth of paralysis, determined by train-of-four (TOF) monitoring, correlates with gas exchange in moderate to severe ARDS. This was a retrospective review of moderate to severe ARDS patients who were prescribed >12 hours of continuous infusion cisatracurium between January 1, 2013, and December 31, 2014, with a PaO2:FiO2 ratio <150 and documented TOF and arterial blood gases. Patients were evaluated for inclusion at 12, 24, and 48 hours after initiation of neuromuscular blockade. A total of 378 patients were screened for inclusion, with 107 evaluable patients meeting criteria at baseline. Poor correlation existed between TOF and oxygenation index (OI) at 12 (τ = 0.03), 24 (τ = 0.15) and 48 hours (τ = 0.08). When controlling for proning and baseline OI, the depth of paralysis did not have a significant effect on OI at 12, 24, or 48 hours. This evaluation demonstrates that the use of TOF monitoring for neuromuscular blockade does not correlate with gas exchange markers in moderate to severe ARDS.