Safety and Efficacy of Sodium Bicarbonate Ringer Injection

Objectives 1. To observe whether sodium bicarbonate Ringer injections can reduce the incidence of postoperative complications in elderly patients undergoing abdominal surgery. 2. To observe the effects of sodium bicarbonate Ringer injections on the internal environment, such as water, electrolytes, acid-base balance, and other physiological indexes, in the perioperative period of elderly patients undergoing abdominal surgery. Research design：This study adopts a multicenter, prospective, randomized, controlled, pragmatic clinical trials (PCT) research design. Sample size：5000 cases. Indication：The experimental group is the elderly patients undergoing abdominal surgery who were administered sodium bicarbonate Ringer injections intraoperatively; the control group is the elderly patients with abdominal surgery who were administered lactated Ringer's injections intraoperatively. Observational index Preoperative baseline data collection: General patient information: basic information (age, height, and weight), preoperative diagnosis, past history, auxiliary examination results, etc. Intraoperative data collection: Perioperative vital signs information and arterial blood gas analysis results; The surgical method, operation time, and anaesthesia time; Intraoperative fluid management: The total amount of intraoperative fluids, blood transfusion volume, bleeding volume, urine volume, types and dosage of vasoactive drugs, diuretic dosage, sodium bicarbonate dosage. Postoperative index: Postoperative blood biochemical examination: liver function, renal function (urea nitrogen, creatinine), osmotic pressure, lactic acid, and blood sugar levels; Postoperative complications and treatment status Postoperative recovery: postoperative outcome, length of hospital stay, admission to ICU (duration of stay), postoperative eating time, out of bed activity time, gastrointestinal recovery time (exhaust), time for removal of various tubes (gastric tube, urinary tube, and drainage t