Risk of age older than 65 years for 30-day cardiac complication may be comparable to low-to-moderate risk according to revised cardiac risk index in non-cardiac surgery.

Revised cardiac risk index (RCRI) is widely used for surgical patients without containing age as a risk factor. We investigated age older than 65 years with respect to low-to-moderate risk of RCRI. From January 2011 to June 2019, a total of 203,787 consecutive adult patients underwent non-cardiac surgery at our institution. After excluding high-risk patients defined as RCRI score > 2, we stratified the patients into four groups according to RCRI and age (A: age < 65 with RCRI < 2, [n = 148,288], B: age ≥ 65 with RCRI < 2, [n = 42,841], C: age < 65 with RCRI = 2, [n = 5,271], and D: age ≥ 65 with RCRI = 2, [n = 5,698]). Incidence of major cardiac complication defined as a composite of cardiac death, cardiac arrest and myocardial infarction was compared. After excluding 1,689 patients with high risk (defined as RCRI score > 2), 202,098 patients were enrolled. The incidence with 95% confidence interval of major cardiac complication for A, B, C, and D groups was 0.3% (0.2-0.3), 1.1% (1.0-1.2), 1.8% (1.6-1.8), and 3.1% (2.6-3.6), respectively. In a direct comparison between B and C groups, old patients with RCRI < 2 showed a significantly lower risk compared to younger patients with RCRI = 2 (odd ratio, 0.62; 95% confidence interval, 0.50-0.78; p < 0.001). In non-cardiac surgery, the risk of age older than 65 years was shown to be comparable with low-to-moderate risk according to RCRI.

Frequency and risk factors for failed weaning from supplemental oxygen therapy after general anesthesia at a postanesthesia care unit: a retrospective cohort study.

BACKGROUND: Patients are administered supplemental oxygen upon emergence from general anesthesia against the risk of hypoxia. However, few studies have assessed the weaning from supplemental oxygen therapy. This study investigated the frequency and risk factors of failure to discontinue supplemental oxygen at a postanesthesia care unit (PACU). METHODS: This retrospective cohort study was conducted in a tertiary hospital. We reviewed the medical records of adult patients admitted to the PACU after general anesthesia for elective surgery between January 2022 and November 2022. The primary endpoint was the frequency of failed weaning from supplemental oxygen therapy at PACU. A failed weaning was defined as oxygen saturation (SpO2) < 92% after discontinuing oxygen administration. The rate of failed discontinuation of supplemental oxygen at the PACU was assessed. Demographics, intraoperative, and postoperative factors were explored to determine potential associations with failed weaning from supplemental oxygen therapy using logistic regression analysis. RESULTS: We analyzed 12,109 patients. We identified 842 cases of failed weaning from supplemental oxygen therapy, with a frequency of 1:14 (95% confidence interval [CI], 1:15-1:13). Risk factors that showed the strongest associations with failed weaning included postoperative hypothermia (odds ratio [OR], 5.42; 95% CI, 4.40-6.68; P < 0.001), major abdominal surgery (OR, 4.04; 95% CI, 3.29-4.99; P < 0.001), and preoperative SpO2 < 92% in room air (OR, 3.15; 95% CI, 2.09-4.64; P < 0.001). CONCLUSION: In the analysis of more than 12,000 general anesthetics, an overall risk of failed weaning from supplemental oxygen therapy of 1:14 was observed. The identified risk factors may help determine the discontinuation of supplemental oxygen administration at PACU. TRIAL REGISTRATION: Not applicable.

The Requirement of Isoflurane and Remifentanil During Liver Transplantation Using Bispectral Index and Surgical Pleth Index: An Observational Study.

BACKGROUND: During liver transplantation (LT), patients and surgical factors potentially influence the pharmacokinetics of the anesthetic agents. The aim of this study was to investigate the requirement of isoflurane and remifentanil according to severity of liver disease during LT under balanced anesthesia. METHODS: We enrolled 44 patients undergoing LT. Anesthetic depth was maintained within the bispectral index score of 40 to 60 and Surgical Pleth Index of 20 to 60. Patients were divided into 2 groups according to their median Model for End-Stage Liver Disease (MELD) score: low MELD group and high MELD group. We compared end-tidal inhaled anesthetics and remifentanil consumption. RESULTS: Patients were divided into 2 groups according to median value of MELD score: MELD score <16 (low MELD group; n = 20) or MELD ≥16 (high MELD group; n = 20). There was no significant difference between the 2 groups in end-tidal concentration of isoflurane during 3 phases. However, the remifentanil requirement was lower in the high MELD group during the dissection and anhepatic phases (mean (SD), 0.105 (0.067) vs 0.064 (0.055) µg/kg/min; P = .037, and 0.167 (0.096) vs 0.108 (0.079) µg/kg/min; P = .039, respectively; low MELD group vs high MELD group) with no significant difference during the neohepatic phase. CONCLUSIONS: The severity of liver dysfunction based on MELD score affected the intraoperative remifentanil requirement during LT. Patients with cirrhosis are required to use analgesics appropriate to their individual patient characteristics in clinical practice.