Postoperative pain after vitreo-retinal surgery is influenced by surgery duration and anesthesia conduction

BACKGROUND: The control of postoperative pain (POP) is a key component of perioperative care. POP after vitreoretinal surgery (VRS) has been under-investigated, and its incidence remains elusive. METHODS: In order to assess POP after VRS, the associated risk factors and efficacy of the analgesic protocol in use at our institution, we made a one-year retrospective study on patients undergoing VRS. Patients aged >18 years, ASA Class I-III undergoing VRS entered the study. POP was evaluated by measuring a Numerical Rating Scale (NRS), and analgesic consumption. RESULTS: A total of 782 patients entered the study. Patients received locoregional (LRA) or general anesthesia (GA) with supplemental block. Twenty-two percent of patients needed analgesics (acetaminophen in 97% of cases), mostly between two and six hours after surgery. The univariate analysis showed a positive association between POP and duration of surgery (P<0.0001) and glaucoma (P=0.04), and a negative association with age (P=0.008), analgesic administration at the end of surgery (P=0.005) and the intraoperative administration of remifentanil for surgery under LRA (P=0.02); sedation to execute the block for LRA did not reduce POP. Patients treated with GA with supplemental block had less pain compared to those treated with LRA with/without remifentanil (P=0.03, P=0.002, respectively). The multivariate analysis confirmed a positive correlation between POP and duration of surgery (P=0.0007) and a negative correlation with the intraoperative remifentanil administration during LRA (P=0.04), and with GA with supplemental block (P=0.01). CONCLUSIONS: The incidence of POP after VRS is low but not absent, especially for long procedures, it does not require postoperative opioids and can be modified by anesthesiologic choices.