Residual Neuromuscular Blockade in Cardiac Surgery Patients

The purpose of this project is to determine if reversal of neuromuscular blockade in cardiac surgery patients expedites time to extubation in fast track patients.

Neuromuscular blocking agents are used as part of most general anesthetics to help facilitate tracheal intubation and optimal surgical conditions (Barish et al). These medications cause universal paralysis of patients while unconscious. After most surgeries where extubation is planned, the standard of care is to "reverse" any residual neuromuscular blockade with either anticholinesterase treatment (specifically neostigmine) or sugammadex. Despite adequate reversal, residual neuromuscular blockade is a common problem seen in the post-anesthetic care unit (PACU). It leads to issues of airway obstruction, hypoxemia, respiratory complications including atelectasis and pneumonia and muscle weakness (Brull et al). The investigators posit that these complications are likely amplified in patients who require post-operative intensive care unit admission. In particular, the investigators hypothesize that cardiac surgery patients are at risk. Elective cardiac surgery patients are routinely admitted to the CVICU still intubated and ventilator-dependent immediately following surgery. The goal of uncomplicated cardiac surgery patients (fast track cardiac surgery patients) is to extubate them within 6 hours of ICU arrival. However, standard of care throughout the US does not include reversal of their neuromuscular blockade. By the time these patients meet extubation criteria, most providers believe that the neuromuscular blockade should have worn off and therefore do not administer reversal (Murphy et al). The investigators hypothesize that residual neuromuscular blockade delays time to extubation and increases respiratory complications in fast track cardiac surgery patients. By administering reversal of neuromuscular blockade in patients with a Train Of Four ratio of <0.9 we anticipate that there will be an increase from 60 to 85% of patients being successfully extubated within 6 hours of arrival to the ICU and a decrease in composite respiratory complications.

Patient's will receive sugammadex at the end of the case for reversal of neuromuscular blockade. The dosing will be determined based on the patient's weight and TOF ratio by the pharmacy. It will be a one time dose at the end of the case

Patient's will receive neostigmine/glycopyrrolate at the end of the case for reversal of neuromuscular blockade. The dosing will be determined based on the patient's weight (50mcg/kg of neostigmine with an equivalent volume to volume ratio of glycopyrrolate). It will be a one time dose at the end of the case

If the patient is extubated in the intensive care unit but then develops respiratory failure and requires mechanical ventilation again

Inclusion Criteria: All outpatients >18 years of age scheduled for elective coronary artery bypass graft surgery (CABG), aortic valve replacement (AVR), or combination CABG/AVR Exclusion Criteria: Chronic kidney disease stage IV or V Liver disease, defined as AST, ALT or ALP > 1.5x upper limit of normal Inpatient status Allergy to rocuronium

Zhu F, Lee A, Chee YE. Fast-track cardiac care for adult cardiac surgical patients. Cochrane Database Syst Rev. 2012 Oct 17;10:CD003587. doi: 10.1002/14651858.CD003587.pub2.

Richey M, Mann A, He J, Daon E, Wirtz K, Dalton A, Flynn BC. Implementation of an Early Extubation Protocol in Cardiac Surgical Patients Decreased Ventilator Time But Not Intensive Care Unit or Hospital Length of Stay. J Cardiothorac Vasc Anesth. 2018 Apr;32(2):739-744. doi: 10.1053/j.jvca.2017.11.007. Epub 2017 Nov 8.