Brittany Verkerk, PharmD, BCCCP,
Clinical Pharmacist
UC Davis Health
Sacramento, California, United States
Disclosure information not submitted.
Tommy Lam, PharmD
PGY1 Pharmacy Resident
University of California Davis Health, United States
Disclosure information not submitted.
Rachelle Firestone, PharmD, BCCCP
Clinical Pharmacist, Adult Critical Care
University of California Davis Medical Center
Diamond Springs, California
Disclosure information not submitted.
Jeremiah Duby, BCPS, PharmD, BCCCP
Clinical Pharmacy Specialist, Critical Care
University of California Davis Medical Center
Davis, California, United States
Disclosure information not submitted.
Schirin Tang, MD
Health Sciences Assistant Clinical Professor
University of California Davis Health, United States
Disclosure information not submitted.
Title: Intensity of Therapeutic Paralysis in ARDS Does Not Correspond with Lung-Protective Ventilation
Introduction/Hypothesis: Current practice guidelines suggest escalation to therapeutic paralysis in patients with moderate-to-severe acute respiratory distress syndrome (ARDS) to facilitate lung-protective ventilation. Core tenants of this strategy include targeting a tidal volume of less than 8 mL/kg and ventilator synchrony. Peripheral nerve stimulation is used to titrate intensity of neuromuscular blocking agents (NMBAs) by measuring train of four (TOF); however, there is limited evidence to support this practice.
Methods: This retrospective, observational cohort study included adult patients with moderate-to-severe ARDS on NMBAs for at least 48 hours. Correspondence between TOF and compliance with lung-protective ventilation was evaluated. Subjects were divided into three groups based on level of paralysis: deep (TOF 0), moderate (TOF 1-2), and light (TOF 3-4). The primary outcome was the proportion of observations within the target tidal volume of less than 8 mL/kg. Secondary outcomes included rate of over-breathing the ventilator, mean tidal volume, and estimated medication costs. A Chi-square test for independence was used to evaluate the primary outcome and the rate of over-breathing the ventilator. A one-way ANOVA was used to evaluate mean tidal volume and estimated medication costs.
Results: There were 151 patients screened, and 100 patients met criteria for inclusion in this study. The most common reason for exclusion was burn injury. The average age was 55 years and 61% of the population was female. The most common causes of ARDS were trauma (31%) and bacterial pneumonia (22%). There were 70 excursions above the target tidal volume out of 789 TOF observations during the study period. For the primary outcome, the proportion of observations that achieved lung-protective ventilation were 248/273 (90.8%), 315/361 (87.3%), and 141/155 (91.0%) in the deep, moderate, and light paralysis groups, respectively (p=0.26). Additionally, there was no difference in rate of over-breathing the ventilator (97.8%, 98.1%, and 96.1%, p=0.41), mean tidal volumes (6.27 + 0.94 mL/kg, 6.42 + 1.28 mL/kg, and 6.38 + 1.19 mL/kg, p=0.24), and estimated medication costs ($359, $264, and $309, p=0.06).
Conclusions: Titrating NMBAs to a goal TOF of one to two twitches does not improve compliance with lung-protective ventilation.