Perioperative Opioid Use and Chronic Post-Surgical Pain after Liver Transplantation: A Single Center Observational Study

Abstract

Objectives: To investigate the opioid requirements and prevalence of chronic postsurgical pain (CPSP) in liver transplant (LT) recipients and to evaluate the association of opioid use with postoperative survival.

Design: Retrospective analysis.

Setting: A large academic medical center.

Patients: Cadaveric liver transplants recipients from 2008 to 2016.

Interventions: Analysis of demographic, perioperative, and outcome data.

Measurements and main results: This study measured the incidence and quantity of preoperative opioid use, postoperative opioid requirements, the incidence of CPSP, and survival in patients with and without CPSP. Opioid requirements were calculated in morphine milligram equivalents. In total, 322 LT recipients satisfied the inclusion criteria. The cohort of interest included 61 patients (18.9%) who were prescribed opioids before LT, compared to the control group of 261. Postoperative opioid requirements were significantly higher in the cohort of interest in the first 24 hours (205.9 ± 318.5 v 60.4 ± 33.6 mg, p < 0.0001) and at 7 days after transplant (57.0 ± 70.6 mg v 19.2 ± 15.4 mg, p < 0.0001). Incidence of CPSP was significantly higher in the cohort of interest at 3 months (70.5% v 45.5%, p < 0.0001), at 2 years (38% v 12%), and at 5 years (29.8% v 6.9%) postoperatively. CPSP was a significant risk factor for patient mortality after transplantation (p = 0.038, HR 1.26).

Conclusions: Opioid use is relatively frequent in patients waiting for LT. It significantly affects the postoperative opioid requirements and the incidence of CSPS. CPSP may significantly affect survival after LT.

Keywords: chronic pain; liver transplant; morbidity; opioids.