Incision cryotherapy was found to be a low-cost, pragmatic intervention for reducing postoperative pain and opioid consumption, according to results of a systematic review and meta-analysis published in Annals of Surgery.
Investigators from the University of Toronto in Canada searched publication databases for randomized controlled trials of postoperative cryotherapy with the outcomes of postoperative pain, total opioid use, length of hospital stay, and surgical site infection. Cryotherapy was defined as gel packs, ice bags, frozen bags, or any cold treatment delivered over a closed surgical wound.
This analysis included 51 trials published between 1989 and 2020, comprising 3,425 patients. The trials included patients who had undergone orthopedic (n=2175), gynecologic and obstetric (n=579), general (n=372), cardiothoracic (n=114), neurologic (n=97), and plastic (n=88) surgery. Most included studies (82.4%) assessed cryotherapy compared with no cryotherapy and the remainder (17.6%) had multiple cryotherapy treatment modality arms.
On postoperative day 1, cryotherapy decreased pain (n=1574; standardized mean difference [SMD], -0.50; 95% CI, -0.71 to -0.29; I2, 74%). A similar finding was reported on postoperative day 2 (n=1082; SMD, -0.63; 95% CI, -0.91 to -0.35; I2, 83%). Among the 17 trials with postoperative pain data that could not be pooled, 10 found no effect of cryotherapy on pain and the other 7 found a pain-reducing effect.
Cryotherapy was observed to reduce morphine milligram equivalents (MME; n=1125; mean difference [MD], -7.43; 95% CI, -12.42 to -2.44; I2, 96%) and MME/kg (n=312; MD, -0.89; 95% CI, -1.45 to -0.33; I2, 99%). Among the 8 trials that could not be pooled, half of the studies showed a reduction in the number of pills consumed and the other half found no effect.
No significant effect of cryotherapy was observed for length of hospital stay (n=1145; MD, 0.03; 95% CI, -0.38 to 0.44; I2, 78%) or surgical site infection (n=668; risk ratio [RR], 2.74; 95% CI, 0.83-9.03; I2, 0%).
This study was limited by the clinical heterogeneity and variability in reported outcomes, making it infeasible to pool all data.
Any cryotherapy applied over surgical incisions was found to decrease postoperative pain and opioid consumption and may be an effective, inexpensive strategy for addressing postoperative pain.
Muaddi H, Lillie E, Silva S, et al. The effect of cryotherapy application on post-operative pain: a systematic review and meta-analysis. Ann Surg. Published online December 2, 2021. doi:10.1097/SLA.0000000000004987