Cryoablation in lung transplantation: Its impact on pain, opioid use, and outcomes

Abstract

Objective: To assess the effect of intraoperative cryoablation on postoperative patient-reported pain, opioid use, and clinical outcomes in lung transplantation.

Methods: We performed a single-center retrospective cohort study of adult lung transplant recipients from August 2017 to September 2018. We compared outcomes of patients who received intraoperative cryoablation of the intercostal nerves with those who did not. Primary outcomes were postoperative patient-reported pain scores and opioid use. Secondary outcomes included postoperative sedation and agitation levels and perioperative outcomes. Data were abstracted from patients' electronic health records.

Results: Of the 102 patients transplanted, 45 received intraoperative cryoablation (intervention group) and 57 received the standard of care, which did not include intercostal or serratus blocks or immediate postoperative epidural placement (control group). The intervention group had significantly lower median and maximum postoperative pain scores at days 3 and 7 and significantly lower oral opioid use at days 3, 7, and 14 compared with the control group. Chronic opioid use at 3 and 6 months' posttransplant was lower in the intervention group. Differences in perioperative outcomes, including length of mechanical ventilation, sedation and agitation levels, and hospital stay, were not clinically meaningful. Survival at 30 days and 1 year was superior in the intervention compared with the control group.

Conclusions: Findings suggest that use of intraoperative cryoablation is an effective approach for treating pain and reducing opioid use in patients who undergo lung transplant, but a randomized study across multiple institutions is needed to confirm these findings.

Keywords: lung transplantation; pain; patient-reported outcomes.

Figure depicts our study's intervention, cryoablation of the intercoastal nerves.

Figure 1

Median pain scores. Median pain score by postoperative day for intervention versus control groups. Greater values reflect greater pain.

Figure 2

Maximum pain scores. Maximum pain per postoperative day for intervention versus control groups. Maximum pain level defined as the greatest patient-reported pain score per postoperative day. Greater values reflect greater pain.

Figure 3

Oral opioid use. Oral opioid use in morphine milligram equivalents per postoperative day for intervention versus control groups.

Figure 4

Postoperative Richmond Agitation-Sedation Scores (RASS) comparisons for intervention versus control groups. RASS 10-point scale includes 4 levels of anxiety or agitation (+1 “restless” to +4 “combative”), 1 level to denote a calm and alert state (0), and 5 levels of sedation (−1 “drowsy” to −5 “unarousable”).

Figure 5

Percent predicted FEV1. Comparisons for percent predicted FEV1 over time for the intervention and control group. The triangles (intervention group) and squares (control group) depict the median percent predicted FEV1 for the specified month after transplant. Bars demonstrate interquartile ranges. FEVI, Expiratory volume at 1 second.

Figure E1

Standard intraoperative anesthesia and postoperative pain management protocol. This chart presents our standardized intraoperative anesthesia and postoperative pain management protocol for lung transplantation. IV, Intravenous; RASS, Richmond Agitation-Sedation Scores; NRS, Numeric Rating Scale; PCA, patient-controlled analgesia.

Figure E2

Study flow diagram. Presented are data on the number of patients assessed for eligibility, excluded and exclusion criteria, patients eligible, and allocation to intervention and control.