Postoperative awake paralysis in the intensive care unit after cardiac surgery due to residual neuromuscular blockade: a case report and prospective observational study.

Purpose: We report a case of awake paralysis due to residual neuromuscular blockade (NMB) in the intensive care unit (ICU) in a patient following fast-track cardiac surgery. As a result of this case, we performed a prospective quality assurance audit to investigate the incidence of residual paralysis in the ICU in a similar population of cardiac surgery patients.

Clinical Features And Audit Methods: A 73-yr-old woman (69 kg) underwent coronary artery bypass surgery under anesthesia induced with intravenous sufentanil 25 µg, midazolam 5 mg, ketamine 25 mg, and rocuronium 100 mg (followed by two additional 50-mg doses during surgery) and maintained with sevoflurane. Postoperatively in the ICU, the patient was initially sedated with propofol (50 mg·hr(-1)) but failed to awaken 90 min after its cessation. As train-of-four neurostimulation showed residual paralysis, she was re-sedated. Neostigmine 3 mg and glycopyrrolate 0.6 mg were administered, and she was extubated 30 min later. During this episode of residual paralysis, the patient was conscious and reported explicit memory of the events. She was discharged on day 7 without psychological distress related to her postoperative awake paralysis. We subsequently performed a prospective audit in 50 consecutive patients to determine the timing of NMB dosing and to quantify the incidence of residual paralysis after fast-track cardiac surgery.

Results: Of the 50 patients studied, 24 (48%) had received an NMB during the last hour of surgery and 33 (66%) had evidence of residual paralysis during the immediate postoperative period.

Conclusion: Postoperative residual paralysis after fast-track cardiac surgery was common in our institution and likely contributed to the reported case of postoperative awake paralysis. We suggest that an NMB not be administered after intubation in fast-track patients. If given, however, it must be well communicated to the ICU team upon ICU admission. We further recommend routine assessment of neuromuscular function before sedation is weaned prior to extubation.