Risk factors for hypokalemia and its association with postoperative recovery in patients scheduled for radical gastrectomy: a retrospective study

Background: Hypokalemia is common in patients of various operations, especially gastrointestinal surgery, which seriously affects the safety and enhanced recovery after surgery. Our study aims to explore the risk factors of preoperative hypokalemia of radical gastrectomy for gastric cancer and analyze its impact on postoperative recovery.

Methods: A total of 122 patients scheduled for radical gastrectomy from September, 2022 to December, 2022 were retrospectively analyzed. According to the serum potassium level before skin incision, patients were divided into hypokalemia group (n = 64) and normokalemia group (n = 58). Factors including age, gender, BMI, ASA classification, glutamic pyruvic transaminase (ALT), glutamic oxaloacetic transaminase (AST), creatinine, blood urea nitrogen (BUN), albumin, hypertension history, whether taking calcium channel blockers, β-receptor blockers, angiotensin converting enzyme inhibitors (ACEI) or angiotensin receptor antagonist (ARB), thiazide diuretics and other drugs, anemia history, diabetes mellitus history, inability to eat or intestinal obstruction, vomiting, diarrhea, hypokalemia on admission and whether under cooperation with clinical nurse specialist were compared between groups. Univariate logistic regression analysis was used to determine risk factors for hypokalemia with p < 0.2 included as a cutoff. Multivariate logistic regression was used to analyze the influencing factors of preoperative hypokalemia for the indicators with differences. A receiver operating characteristic (ROC) curve was used to evaluate the efficacy of the regression model. Primary exhaust time and defecation time after surgery were compared between the two groups.

Results: The use of ACEI or ARB [OR 0.08, 95% CI (0.01 to 0.58), p = 0.012] and thiazide diuretics [OR 8.31, 95% CI (1.31 to 52.68), p = 0.025], inability to eat for more than 3 days or intestinal obstruction [OR 17.96, 95% CI (2.16 to 149.43), p = 0.008], diarrhea for more than 48 h [OR 6.21, 95% CI (1.18 to 32.61), p = 0.031] and hypokalemia on admission [OR 8.97, 95% CI (1.05 to 77.04), p = 0.046] were independent influencing factors of hypokalemia before skin incision. Primary postoperative exhaust time and defecation time was significantly longer in the hypokalemia group than in the normokalemia group, no matter after laparoscopic radical gastrectomy (p = 0.044, p = 0.045, respectively) or open radical gastrectomy (p = 0.033, p = 0.019, respectively).

Conclusion: Early attention and management of serum potassium in patients undergoing radical gastrectomy can better reduce perioperative adverse reactions and promote recovery of gastrointestinal function.