Daily Anesthesiology Research Analysis
Top perioperative studies today refine antiplatelet and metabolic medication management and reassess obesity-related pulmonary risk. An RCT shows coronary bypass 2–3 days after ticagrelor cessation is noninferior for bleeding versus 5–7 days, shortening hospital stay. Large cohorts suggest emergency surgery in SGLT2 inhibitor users does not raise postoperative DKA risk, and overweight/class 1 obesity is associated with lower postoperative pulmonary complications.
Summary
Top perioperative studies today refine antiplatelet and metabolic medication management and reassess obesity-related pulmonary risk. An RCT shows coronary bypass 2–3 days after ticagrelor cessation is noninferior for bleeding versus 5–7 days, shortening hospital stay. Large cohorts suggest emergency surgery in SGLT2 inhibitor users does not raise postoperative DKA risk, and overweight/class 1 obesity is associated with lower postoperative pulmonary complications.
Research Themes
- Perioperative antiplatelet management and bleeding risk
- Metabolic medication management (SGLT2 inhibitors) and postoperative safety
- Obesity and postoperative pulmonary complications
Selected Articles
1. Early vs Delayed Bypass Surgery in Patients With Acute Coronary Syndrome Receiving Ticagrelor: The RAPID CABG Randomized Open-Label Noninferiority Trial.
In ACS patients previously treated with ticagrelor and requiring CABG, performing surgery 2–3 days after stopping ticagrelor was noninferior to delaying 5–7 days for severe/massive perioperative bleeding and chest tube output. Early surgery also reduced hospital length of stay.
Impact: High-quality randomized evidence addresses a frequent perioperative dilemma on antiplatelet timing for CABG and supports accelerating surgical care without excess bleeding.
Clinical Implications: For ACS patients on ticagrelor proceeding to CABG, anesthesia and surgical teams can schedule surgery 2–3 days after cessation rather than waiting 5–7 days, potentially shortening ICU and hospital stays while maintaining bleeding safety.
Key Findings
- Per-protocol severe/massive UDPB: 4.6% (early) vs 5.2% (delayed); noninferiority met (P=0.03).
- 12-hour chest tube drainage noninferior: median 470 mL (early) vs 495 mL (delayed).
- Hospital stay shorter with early strategy: median 9 vs 12 days (P<0.001).
Methodological Strengths
- Randomized, prespecified noninferiority design with registered protocol (NCT02668562).
- Clinically relevant endpoints (UDPB class 3/4 bleeding, chest tube output, LOS) with per-protocol and superiority analyses.
Limitations
- Open-label design may introduce performance bias.
- Modest sample size (n=143) limits precision for rare bleeding events.
Future Directions: Replicate findings in larger, multicenter pragmatic trials and evaluate cost-effectiveness and protocols integrating point-of-care platelet function testing.
IMPORTANCE: Perioperative bleeding is a major concern in patients receiving ticagrelor for acute coronary syndromes (ACS) when coronary artery bypass graft (CABG) surgery is required. OBJECTIVE: To evaluate whether early CABG surgery at 2 to 3 days after ticagrelor cessation is noninferior to waiting 5 to 7 days. DESIGN, SETTING, AND PARTICIPANTS: RAPID CABG was a noninferiority, open-label randomized trial with 6 months of follow-up. Participants were patients with ACS who had received ticagrelor and required CABG. Patients were enrolled in tertiary centers in Canada between January 2016 and March 2021. Data were analyzed from March 2021 to December 2023. INTERVENTION: Early or delayed CABG. MAIN OUTCOMES AND MEASURES: The primary outcome was based on noninferiority comparison of class 3 or 4 universal definition of perioperative bleeding (UDPB). Noninferiority was prespecified as 8% between groups. Twelve-hour chest tube drainage was reported as a noninferiority comparison. Other bleeding, ischemic, and length-of-stay outcomes were assessed for superiority. RESULTS: Among 143 randomized patients, the median (IQR) age was 65 (58-72) years; there were 117 male patients (82%) and 26 female (18%). Of these, 123 patients (86.0%) underwent surgery in the allocated time frame (per protocol). The median (IQR) time to surgery was 3 (2-3) days in the early group and 6 (5-7) days in the delayed group (P < .001). In a per-protocol analysis, severe or massive UDPB occurred in 3 of 65 early-group patients (4.6%) and 3 of 58 patients (5.2%) in the delayed group (between-group difference, -0.6%; 95% CI, -8.3% to 7.1%; P = .03 for noninferiority). Median (IQR) chest tube drainage was 470 (330-650) mL vs 495 (380-610) mL (between-group difference -25 mL; 95% CI, -111.25 to 35; P = .01 for noninferiority). Median (IQR) hospital stay was 9 (7-13) days and 12 (10-15) days for the early and delayed groups (P < .001). CONCLUSION AND RELEVANCE: This study found that an early surgical strategy, 2 to 3 days after ticagrelor cessation, was noninferior in incurring perioperative bleeding. The data support a reduction in the delay between ticagrelor cessation and CABG surgery and may decrease hospital length of stay. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02668562.
2. Preoperative SGLT2 Inhibitor Use and Postoperative Diabetic Ketoacidosis.
In 34,671 adults with type 2 diabetes undergoing emergency surgery, preoperative SGLT2 inhibitor exposure was not associated with higher postoperative DKA within 14 days after multivariable adjustment (ATE 0.2%, 95% CI −1.7% to 2.2%). Findings were robust across sensitivity analyses.
Impact: Addresses a common perioperative management question with large-scale data, challenging conservative withholding recommendations and potentially improving glycemic control continuity.
Clinical Implications: For emergency surgery, prior SGLT2i exposure alone should not trigger automatic ICU-level monitoring for DKA; perioperative teams may consider more liberal withholding strategies, while maintaining vigilance for ketosis in high-risk phenotypes.
Key Findings
- Adjusted postoperative DKA incidence: 3.8% (SGLT2i) vs 3.5% (non-users); ATE 0.2% (95% CI −1.7% to 2.2%).
- Robustness across specifications (e.g., ICU-level care outcome ATE −1.0%; 95% CI −2.9% to 1.1%).
- Most common procedures: laparoscopic cholecystectomy and transurethral procedures; consistent results across surgery types.
Methodological Strengths
- Large national cohort with diverse emergency surgeries and robust adjustment for confounders.
- Causal inference framework reporting average treatment effect with multiple sensitivity analyses.
Limitations
- Observational design relying on administrative codes for DKA may misclassify outcomes.
- Findings pertain to emergency surgery; applicability to elective procedures and specific subgroups requires caution.
Future Directions: Prospective studies and pragmatic trials to define safe withholding intervals for elective surgery and to identify phenotypes at residual DKA risk under liberal strategies.
IMPORTANCE: Case reports of postoperative diabetic ketoacidosis in patients using sodium-glucose cotransporter 2 inhibitor (SGLT2i) medications underlie guidance by the US Food and Drug Administration to withhold SGLT2i medication for at least 3 days prior to surgery. Given the potential negative consequences associated with preoperative medication withholding, a large-scale evaluation of the risk of diabetic ketoacidosis in this population is needed. OBJECTIVE: To estimate the association between preoperative SGLT2i medication use and postoperative diabetic ketoacidosis in a population of patients who underwent a variety of emergency surgeries. Emergency surgery was chosen given the assumption that a patient would be unable to withhold their SGLT2i medication per the current guidance. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study was conducted among a nationwide sample of patients aged 18 years or older with type 2 diabetes who were enrolled in commercial or Medicare fee-for-service insurance plans and who underwent 1 of 13 emergency surgeries between January 1, 2016, and December 15, 2022. Emergency surgeries were defined as those occurring on the same day or the 1 to 2 days after an emergency department claim. Data were analyzed from November 2023 through December 2024. EXPOSURE: SGLT2i medication use. MAIN OUTCOMES AND MEASURES: Diabetic ketoacidosis, defined by diagnosis codes, in the 0 to 14 days after surgery. RESULTS: Among 34 671 patients with type 2 diabetes who underwent emergency surgery (mean [SD] age, 63.9 [14.0] years; 19 175 female [55.3%] and 15 496 male [44.7%]), the most common surgeries were laparoscopic cholecystectomy (9385 patients) and transurethral procedures (12 246 patients). There were 2607 patients (7.5%) who used SGLT2i medications and 32 064 patients (92.5%) who did not. Unadjusted incidence of diabetic ketoacidosis was 127 patients (4.9%) for those exposed to SGLT2i medications and 1115 patients (3.5%) for those unexposed. After accounting for covariates, including demographic characteristics, indicators of diabetic severity, comorbidities, and surgery type, the incidence of the outcome was 3.8% for those exposed to SGLT2i medications and 3.5% for those unexposed. The average treatment effect [ATE] was 0.2% (95% CI, -1.7% to 2.2%). Results were robust to alternate specifications (eg, intensive care unit-level care as the outcome: ATE, -1.0%; 95% CI, -2.9% to 1.1%). CONCLUSIONS AND RELEVANCE: This study found that preoperative use of SGLT2i medications in patients undergoing emergency surgery was not associated with an increased risk for postoperative diabetic ketoacidosis compared with no use of SGLT2i medications. These findings may justify liberalizing current guidance on preoperative SGLT2i medication withholding periods.
3. The association between BMI and postoperative pulmonary complications in adults undergoing non-cardiac, non-obstetric surgery: a retrospective cohort study.
In 125,082 non-cardiac, non-obstetric surgeries, 5.3% developed postoperative pulmonary complications. After risk adjustment, overweight and class 1 obesity were associated with lower PPC risk compared with normal BMI, indicating an obesity paradox for pulmonary complications.
Impact: Large single-center analysis challenges conventional assumptions about obesity and pulmonary risk, informing perioperative risk stratification and counseling.
Clinical Implications: Avoid reflexively labeling overweight/class 1 obesity as higher PPC risk; prioritize modifiable risk factors (e.g., smoking, OSA, pulmonary hygiene) and individualized respiratory optimization rather than BMI alone.
Key Findings
- Among 125,082 adults, 5.3% experienced postoperative pulmonary complications.
- Overweight and class 1 obesity were associated with lower adjusted PPC risk versus normal BMI.
- Results were consistent across multiple analytic approaches, including restricted cubic splines and sensitivity analyses.
Methodological Strengths
- Very large contemporary surgical cohort with multivariable modeling and spline analyses.
- Comprehensive subgroup and sensitivity analyses to test robustness.
Limitations
- Single-center retrospective design may limit generalizability and residual confounding remains possible.
- Abstract lacks detailed stratified estimates; full data needed to quantify effect sizes by BMI category.
Future Directions: Prospective multicenter validation and mechanistic studies to disentangle body composition, fitness, and pulmonary physiology in PPC risk.
INTRODUCTION: Conflicting results have been reported regarding the influence of BMI on postoperative adverse events. The aim of this study was to investigate the association between BMI and postoperative pulmonary complications in adults undergoing non-cardiac, non-obstetric surgical procedures. METHODS: This large-scale retrospective study included 125,082 adults who underwent surgery at a university-affiliated tertiary care hospital between 2019 and 2023. The primary endpoint was the incidence of postoperative pulmonary complications. Multivariable logistic regression analyses, subgroup analyses, sensitivity analyses and restricted cubic splines were used to assess the association between BMI and postoperative pulmonary complications. RESULTS: A total of 6671 patients (5.3%) developed one or more postoperative pulmonary complications. After adjusting for confounders, compared with those patients with a normal weight (BMI 18.5-24.9 kg.m DISCUSSION: Patients who were overweight or living with class 1 obesity undergoing non-cardiac, non-obstetric surgery had paradoxically lower risks of postoperative pulmonary complications compared with those of a normal weight. These findings may contradict traditional assumptions about surgical risk and obesity, highlighting the need to re-evaluate the relationship between BMI and postoperative pulmonary complications.