Introduction: Perioperative anesthesia and analgesia exacerbate immunosuppression in immunocompromised cancer patients. The natural killer (NK) cell is a critical part of anti-tumor immunity. We compared the effects of two different anesthesia and analgesia methods on the NK cell cytotoxicity (NKCC) in patients undergoing breast cancer surgery.

Background: Although acetaminophen has been used widely and is well tolerated in children, its efficacy and safety have not been clarified when combined with an opioid in intravenous parent-/nurse-controlled postoperative analgesia. Methods: Sixty-three children (aged 6-24 months) who had undergone elective ureteroneocystostomies were enrolled in this prospective, randomized, double-blinded study. After the surgery, an analgesic pump was programmed to deliver fentanyl at a basal infusion rate of 0.25 microg.kg(-1).h(-1) and 0.25 microg/kg bolus after a loading dose of 0.5 microg/kg(-1). In the fentanyl-acetaminophen group, acetaminophen was coadministered as a solution mixture at a basal infusion rate of 1.5 mg.kg(-1).h(-1) and 1.5 mg/kg bolus after a loading dose of 15 mg/kg, whereas saline was administered to the fentanyl group. Results: Postoperative pain scores were similar between the two groups. The total dose (micrograms per kilogram per day, mean+/-SD) of fentanyl at postoperative days 1 (8.3+/-3.7 vs. 18.1+/-4.6, P=0.021) and 2 (7.0+/-2.4 vs. 16.6, P=0.042) was significantly less in the fentanyl-acetaminophen group compared with that in the fentanyl group. The incidences of vomiting (16.1 vs. 56.3%, P=0.011) and sedation (9.7 vs. 46.9%, P=0.019) were significantly lower in the fentanyl-acetaminophen group than those in the fentanyl group. Conclusions: Acetaminophen has significant fentanyl-sparing effects and reduces side effects when combined with fentanyl in intravenous parent-/nurse-controlled analgesia for postoperative pediatric pain management.

Anaesthesia is required for catheter ablation of atrial fibrillation (A-fib) to achieve patient comfort and immobilization to avoid map shifts. This study compared the analgesic and sedative efficacies of dexmedetomidine–remifentanil with those of midazolam–remifentanil for catheter ablation of A-fib. Ninety patients were randomized to receive either intermittent midazolam boluses (1–2 mg) with 3.6–7.2 µg/kg/h of remifentanil (MR group) or dexmedetomidine 0.2–0.7 µg/kg/h after a loading dose of 1 µg/kg with 1.2–2.4 µg/kg/h of remifentanil (DR group). The sedation level assessed by the Ramsay sedation and bispectral index scores, haemodynamic variables, pain score (10-point numerical scale), and satisfaction levels of the patients and cardiologists (5-point numerical scale) were recorded. The Ramsay sedation score was significantly higher, and the bispectral index score was lower in the DR group (P< 0.001) compared with the MR group starting 10 min after drug administration. The incidence of desaturation (SpO₂ < 90%) was significantly greater in the MR group compared with the DR group (15 vs. 1, P < 0.001). The pain score was significantly lower (1.72 ± 1.65 vs. 0.95 ± 1.10, P = 0.021), and the satisfaction levels of interventionists were significantly higher (2.50 ± 0.71 vs. 3.00 ± 0.63, P = 0.001) in the DR group compared with the MR group. The combination of dexmedetomidine and remifentanil provided deeper sedation, less respiratory depression, better analgesia, and higher satisfaction for the interventionist during catheter ablation of A-fib compared with midazolam plus remifentanil, even at a lower dose of remifentanil.