Effect of injection pain and withdrawal movement of propofol and rocuronium in the induction of anaesthesia on postoperative pain outcomes in gynaecologic laparoscopic surgery: a prospective observational study.

INTRODUCTION: The pain experience among individuals may differ from each other. This prospective cohort study aimed to determine the impact of injection pain/withdrawal movement of propofol and rocuronium in the induction of anaesthesia on postoperative pain outcomes in gynaecologic laparoscopic surgery. METHODS: A total of 100 patients aged 19-60 years received propofol and rocuronium injections for the induction of anaesthesia. The incidence of propofol injection pain (PIP) and rocuronium-induced withdrawal movement (RIWM), postoperative pain scores and total opioid consumption were evaluated, and the associations between PIP/RIWM and postoperative pain outcomes were determined. RESULTS: Visual analog scale (VAS) for pain after surgery and total opioid consumption after surgery in patients with PIP or RIWM were significantly higher than in patients without PIP or RIWM. The correlation between PIP and RIWM, VAS at 1 hour, VAS at 24 hours, total opioid consumption were significant and weakly positive (r = 0.249, r = 0.234, r = 0.22, r = 0.234, respectively). Compared with PIP, RIWM correlated more positively with pain score at 1 hour (r = 0.408 vs. r = 0.234, RIWM vs. PIP) and 24 hours (r = 0.398 vs r = 0.227, RIWM vs. PIP) and total opioid consumption after 48 hours (r = 0.457 vs. r = 0.234, RIWM vs. PIP). CONCLUSION: During anaesthesia induction, the occurrence of PIP and RIWM may predict the severity of postoperative pain and total opioid consumption, with RIWM emerging as a stronger predictor than PIP.

Effects of Female Reproductive Hormone Levels on Inadvertent Intraoperative Hypothermia during Laparoscopic Gynecologic Surgery: A Retrospective Study.

Background and Objectives: Female reproductive hormones may affect core body temperature. This study aimed to investigate the effects of female reproductive hormones on inadvertent intraoperative hypothermia in patients who underwent laparoscopic gynecologic surgery under general anesthesia. Materials and Methods: This retrospective study included 660 menstruating and menopausal female patients aged 19-65 years. The patients were divided into two groups according to the occurrence of inadvertent intraoperative hypothermia: non-hypothermia group (N = 472) and hypothermia group (N = 188). After propensity score matching, 312 patients (N = 156 in each group) were analyzed to investigate the association between intraoperative hypothermia and female reproductive hormones. As potential predictors of inadvertent hypothermia, the levels of female reproductive hormones were analyzed using binary logistic regression. Results: The association of estradiol (r = -0.218, p = 0.000) and progesterone (r = -0.235, p = 0.000) levels with inadvertent intraoperative hypothermia was significant but weakly negative before matching; however, it was significant and moderately negative after matching (r = -0.326, p = 0.000 and r = -0.485, p = 0.000, respectively). In a binary logistic analysis, the odds ratio for estradiol was 0.995 (p = 0.014, 0.993 < 95% confidence interval [CI] < 0.998) before matching and 0.993 (p = 0.000, 0.862 < 95% CI < 0.930) after matching, and that for progesterone was 0.895 (p = 0.000, 0.862 < 95% CI < 0.930) before matching and 0.833 (p = 0.014, 0.990 < 95% CI < 0.996) after matching. Conclusions: Estradiol and progesterone levels were associated with inadvertent intraoperative hypothermia. However, the odds ratio for female reproductive hormone levels was close to 1. Therefore, female reproductive hormones may not be a risk factor for hypothermia during gynecologic surgery under general anesthesia. However, a small sample size in this study limits the generalizability of the results.

Impact of the Timing of Rocuronium Injection after Propofol Administration on Temporal Summation of Pain in Gynecologic Laparoscopic Surgery: A Prospective and Controlled Study.

Purpose: Temporal summation of pain, which is defined as the perception of greater pain evoked by repetitive painful stimuli, varies among individuals. This study aimed at determining the impact of the timing of rocuronium after induction with propofol on the temporal summation of pain. Methods: One hundred patients aged 19-60 years underwent gynecologic laparoscopic surgery. Patients were randomly assigned to one of the two groups: group PRi received immediate injections of rocuronium after propofol administration and group PRd received rocuronium injections when the bispectral index score (BIS) decreased to <60 after propofol administration. The grade of rocuronium-induced withdrawal movement (RIWM) according to the timing of propofol injection, the incidence and severity of propofol injection pain (PIP), rescue analgesics, visual analog scale (VAS) score after surgery for postoperative pain, patient-controlled analgesia (PCA) opioid consumption, association between PIP and the grade of RIWM, and associations between PIP, the grade of RIWM, and postoperative pain outcomes were measured. Results: The differences between the incidence and severity of PIP in the two groups were not significant. The grade of the RIWM in the PRd group was significantly reduced compared with the PRi group. Rescue analgesics, severity for postoperative pain, and PCA opioid consumption were not significant. Correlations between the incidence and severity of PIP and the grade of RIWM were weakly negative. Correlations between the grade of RIWM and pain outcomes were moderately positive, but correlations between the severity for PIP and the postoperative pain outcomes were negligible. Conclusion: The timing of rocuronium administration after propofol injection played a role in reducing RIWM. The grade of RIWM was significantly related to pain outcomes compared with the severity of PIP. Therefore, delayed rocuronium injection after induction with propofol reduced temporal summation of pain.