Background and objectives A single injection interscalene block (ISB) is a common regional analgesic technique in patients undergoing arthroscopic shoulder surgery. However, rebound pain after ISB resolution may reduce its overall benefit. Our primary aim was to assess whether perineural dexamethasone reduces the intensity and incidence of rebound pain in patients undergoing arthroscopic shoulder surgery under general anesthesia combined with a preoperative single injection ISB. Methods The patients were randomly assigned to receive single injection ISB using either 0.5% ropivacaine (control) or 0.5% ropivacaine containing 5 mg of dexamethasone. The primary outcomes were the pain score difference before and after ISB resolution, and the incidence of rebound pain. The secondary outcomes were the onset and duration of rebound pain, the presence of sleep disturbances due to postoperative pain, the first time when an analgesic was requested, and pain scores at various predefined time points. Results Pain increase following ISB resolution was lower in the dexamethasone group compared with the control group (4.5±2.4 and 6.9±2.2, respectively, p<0.001). The incidence of rebound pain was significantly lower in the dexamethasone group compared with the control group (37.1% and 82.9%, respectively, p<0.001). The controls experienced greater sleep disturbance during the postoperative period compared with those who received ISB with perineural dexamethasone. Conclusions Perineural dexamethasone added to ISB using ropivacaine led to a much smoother resolution of ISB, reflected in a significantly smaller increase in pain after block resolution, a lower incidence of rebound pain and a lower sleep disturbance during the first postoperative week. Trial registration number Clinical Trial Registry of Korea (KCT0004418).

Background: Pain assessment and management are important in postoperative circumstances as overdosing of opioids can induce respiratory depression and critical consequences. We aimed this study to check the reliability of commonly used pain scales in a postoperative setting among Korean adults. We also intended to determine cut-off points of pain scores between mild and moderate pain and between moderate and severe pain by which can help to decide to use pain medication. Methods: A total of 180 adult patients undergoing elective non-cardiac surgery were included. Postoperative pain intensity was rated with a visual analog scale (VAS), numeric rating scale (NRS), faces pain scale revised (FPS-R), and verbal rating scale (VRS). The VRS rated pain according to four grades: none, mild, moderate, and severe. Pain assessments were performed twice: when the patients were alert enough to communicate after arrival at the postoperative care unit (PACU) and 30 min after arrival at the PACU. The levels of agreement among the scores were evaluated using intraclass correlation coefficients (ICCs). The cut-off points were determined by receiver operating characteristic curves. Results: The ICCs among the VAS, NRS, and FPS-R were consistently high (0.839–0.945). The pain categories were as follow: mild ≦ 5.3 / moderate 5.4 ~ 7.1 /severe ≧ 7.2 in VAS, mild ≦ 5 / moderate 6 ~ 7 / severe ≧ 8 in NRS, mild ≦ 4 / moderate 6 / severe 8 and 10 in FPS-R. The cut-off points for analgesics request were VAS ≧ 5.5, NRS ≧ 6, FPS-R ≧ 6, and VRS ≧ 2 (moderate or severe pain). Conclusions: During the immediate postoperative period, VAS, NRS, and FPS-R were well correlated. The boundary between mild and moderate pain was around five on 10-point scales, and it corresponded to the cut-off point of analgesic request. Healthcare providers should consider VRS and other patient-specific signs to avoid undertreatment of pain or overdosing of pain medication.

Lee HJ, et al. J Korean Med Sci. 2023 May;38(24):e183. https://doi.org/10.3346/jkms.2023.38.e183

Purpose: In pediatric patients, the most common reason for delaying surgical intervention is an upper respiratory tract infection (URI). To date, there has been no consensus regarding the optimal timeframe for deferring surgery in children with URI. We conducted this study to evaluate whether a URI symptom-free period and other risk factors affect the incidence of perioperative respiratory adverse events (RAEs). Patients and Methods: The study population included 267 pediatric patients (aged 0 to 13 years) with a recent URI episode who underwent surgery under general anesthesia. Following a retrospective review of medical records, several risk factors including a URI symptom-free period for intra- and postoperative RAEs were analyzed using univariate and multivariate logistic regression analyses. Results: RAEs occurred in 23 of 267 patients (8.6%). Univariate analysis revealed that abnormal preoperative chest images (odds ratio [OR], 7.48; 95% confidence interval [CI], 2.46– 22.68, p < 0.001) and emergency operations (OR, 2.84; 95% CI, 1.03– 7.81, p = 0.04) were associated with RAEs. Four variables (abnormal preoperative chest images, emergency operations, age under 1 year and symptom-free period of 7– 13 days) with a significance of < 0.20 in the univariate logistic regression analysis were selected as candidate risk factors for the multivariate model. Among the four variables, abnormalities in preoperative chest images (OR, 7.60; 95% CI, 2.28– 25.3, p = 0.001) and a symptom-free period of 7– 13 days (OR, 0.13; 95% CI, 0.02– 0.88, p = 0.04) were independently associated with RAEs in multivariate logistic regression analysis. Conclusion: For pediatric patients who require surgery and have a recent history of URI, procedures should be performed after a URI symptom-free period of at least 1– 2 weeks. Confirming the absence of abnormalities in preoperative chest images can reduce the incidence of perioperative RAEs.

Intraoperative hypotension is a risk factor for perioperative adverse outcomes and highly prevalent in older patients. Frailty has been associated with hemodynamic instability but its impact on postinduction hypotension is unclear. Therefore, we assessed the association between frailty and postinduction hypotension in older patients. We retrospectively evaluated electronic medical records of patients aged ≥ 65 years who were assessed for preoperative frailty and underwent noncardiac surgery under general anesthesia. Reported Edmonton Frail Scale (REFS) scores were used to stratify patients into a non-frail (REFS scores 0–5), prefrail (6–7), and frail (8–18) group. Postinduction hypotension was defined as a mean blood pressure below 65 mmHg or 20% from baseline occurring within the first 20 min after anesthesia induction and evaluated using multivariate logistic regression analysis. Independent factors related to postinduction hypotension in our sample (421 patients) were status of frail (REFS score ≥ 8) compared to non-frail (odds ratio [OR], 2.73; 95% confidence interval [CI], 1.44 to 5.18; p = .002), lower baseline mean blood pressure in the operating room (OR, 0.98; 95% CI, 0.96 to 0.999; p = .034) and at the presurgical center (OR, 0.96; 95% CI, 0.94 to 0.99; p = .003), and orthopedic (compared to urologic) surgery (OR, 2.22; 95% CI, 1.14 to 4.30; p = .019). Preoperative frail status based on REFS scores is associated with postinduction hypotension. Frailty screening tool for older patients may enhance traditional risk calculators and improve patient selection for non-cardiac surgery under general anesthesia.

Complex regional pain syndrome (CRPS) is a condition associated with neuropathic pain that causes significant impairment of daily activities and functioning. Nuclear factor kappa B (NFκB) is thought to play an important role in the mechanism of CRPS. Recently, exosomes loaded with super-repressor inhibitory kappa B (Exo-srIκB, IκB; inhibitor of NFκB) have been shown to have potential anti-inflammatory effects in various inflammatory disease models. We investigated the therapeutic effect of Exo-srIκB on a rodent model with chronic post-ischemia pain (CPIP), a representative animal model of Type I CRPS. After intraperitoneal injection of a vehicle, Exo-srIκB, and pregabalin, the paw withdrawal threshold (PWT) was evaluated up to 48 h. Administration of Exo-srIκB increased PWT compared to the vehicle and pregabalin, and the relative densities of p-IκB and IκB showed significant changes compared to the vehicle 24 h after Exo-srIκB injection. The levels of several cytokines and chemokines were reduced by the administration of Exo-srIκB in mice with CPIP. In conclusion, our results showed more specifically the role of NFκB in the pathogenesis of CRPS and provided a theoretical background for novel treatment options for CRPS.