Opioid Minimization After Liver Transplantation: Results of a Novel Pilot Study

Pain management in liver transplant recipients: a focus on current and future strategies

Liver transplantation is the only curative treatment option for patients with end-stage liver disease. Anesthesiologists and intensivists are fully involved in this procedure due to the perioperative care focus on hemodynamic, respiratory and metabolic support. However, quite surprisingly, postoperative pain management does not have clinical primary consideration in this class of patients due to a combination of factors including the thought that liver transplantation recipients have less pain and require lower doses of analgesics than patients who undergo other types of major abdominal surgery. Other factors contribute to make the management of postoperative pain somewhat complex in this class of patients: 1) drug pharmacokinetics and metabolism by the new liver is not predictable; 2) the multifactorial nature of liver graft recovery; and 3) the alterations of homeostasis, including circulatory, respiratory and metabolic vulnerability, in the days postoperative period. As a result, post-liver transplantation analgesia is underestimated not only from the clinical point of view but also in the literature and only a few papers deal with the management of postoperative pain in this particular class of patients. Thus, in the experts' opinion paper we aimed to report the possible strategies for managing post-LT pain with a focus on opioids alternatives and possible future developments in this particular clinical setting also in the view that improvements in perioperative care have made it possible to adopt fast track and Enhanced Recovery After Surgery-oriented protocols also in this class of patients.

Optimal management of perioperative analgesia regarding immediate and short-term outcomes after liver transplantation - A systematic review, meta-analysis and expert panel recommendations

BACKGROUND

Adequate pain control is essential for patients undergoing liver transplantation (LT). Multiple analgesic strategies have been implemented during the perioperative period. There is no consensus on the optimal perioperative analgesia management.

OBJECTIVES

To provide recommendations, on the optimal perioperative analgesia management for LT.

DATA SOURCES

Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central.

METHODS

A systematic review and meta-analysis following PRISMA guidelines and recommendations using GRADE. Studies describing outcomes, morbidity, mortality, pain scores, intensive care unit and hospital length of stay in patients that received different pain management techniques during and after LT were included (CRD42021243282).

RESULTS

One thousand nine hundred ten articles were screened, but only two randomized controlled trials, one prospective and six retrospective studies were included. The opioid-avoidance protocols included, thoracic epidural analgesia (TEA), Transversus Abdominis Plane (TAP) block, as well as other non-opioid analgesics, resulted in improved short-term outcomes. Mortality was reduced in this group versus control cohorts (OR = 0.51; CI 0.14, 1.83; P = 0.350), Time to extubation, and intensive care unit LOS were shorter; pain scores after surgery were lower in opioid-avoidance group (percentage decrease, 35%, 12%, and 55%, respectively). However, hospital LOS was longer (percentage increase 8%).

CONCLUSIONS

Opioid-avoidance analgesia management for LT results in improved short-term outcomes. (Quality of Evidence; Moderate to low | Grade of Recommendation; Weak). Medications such as acetaminophen(paracetamol), gabapentin, ketamine, tramadol and local anesthesia may be used instead of, or as adjuncts to opioids for postoperative analgesia. Overall evidence remains weak and more robust studies are required.

Impact of a Multimodal Analgesia Protocol on Inpatient and Outpatient Opioid Use in Acute Trauma

BACKGROUND

Multimodal analgesia protocols have been implemented after elective surgery to reduce opioid use, however there is limited data on utility after polytrauma. Therefore, we investigated the impact of a multimodal analgesia protocol on inpatient and post-discharge outpatient opioid use after polytrauma.

METHODS

A retrospective review of patients admitted to a Level I trauma center between September 2017-February 2018 (prior to multimodal protocol; "pre-cohort") and October 2018-April 2019 (after multimodal protocol; "post-cohort") was performed. An outpatient controlled substance registry was utilized to capture morphine milligram equivalents (MME) and gabapentin dispensed in the 6 mo after injury.

RESULTS

620 patients were included (295 pre-cohort, 325 post-cohort). Total inpatient MME decreased from 177.5 mg-130 mg (P= 0.01) between the cohorts. Daily inpatient MME decreased from 70.8 mg-44.7 mg (P< 0.01). Intravenous hydromorphone decreased from 2 mg in the pre-cohort to 1 mg in the post-cohort (P= 0.02). Inpatient oxycodone decreased from 45 mg-30 mg (P= 0.01). Concurrently, gabapentin increased from 0 mg-400 mg in the post-cohort (P< 0.01). Patients in the post-cohort were prescribed fewer MMEs than the pre-cohort at discharge (P< 0.05). However, the number of patients prescribed gabapentin increased from 6.1%-16% (P< 0.01).

CONCLUSION

Implementation of an updated multimodal analgesia protocol decreased total MME, daily MME, hydromorphone, and oxycodone consumed while increasing gabapentin use. This suggests that while reducing opioid usage in-hospital is critical to reducing outpatient usage, multimodal pain protocols may lead to an increase in gabapentin prescriptions and utilization after discharge.