Effect of Obesity Phenotype on Intraabdominal Pressure, Intraoperative Bleeding, and Perioperative Complications in Patients Undergoing Major Lumbar Spinal Surgery: A Prospective Observational Study
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 发起方
- 入组人数
- 90
- 主要终点
- Intraoperative Blood Loss
研究概览
简要总结
Obesity is prevalent among patients with lumbar degenerative disease and is a known risk factor for perioperative complications in spinal surgery. However, most existing evidence relies solely on body mass index (BMI) without distinguishing between central and peripheral obesity phenotypes. Central and peripheral fat distribution may have distinct biomechanical and hemodynamic consequences, particularly with respect to intraabdominal pressure (IAP) changes during prone positioning and intraoperative blood loss.
This prospective single-center observational study aims to evaluate the effect of obesity phenotype - classified as non-obese, centrally obese, or peripherally obese based on BMI and waist-to-hip ratio - on intraabdominal pressure, intraoperative blood loss, and other perioperative outcomes in adult patients undergoing major lumbar spinal surgery (decompression and/or instrumentation)
详细描述
Major lumbar spinal surgery, including lumbar canal stenosis decompression and instrumented fusion, is associated with substantial intraoperative blood loss and notable perioperative morbidity. Obesity is highly prevalent in this patient population due to its role in lumbar degenerative disease pathogenesis. Prone positioning during surgery significantly increases intraabdominal pressure, which in turn may impair venous drainage from the spinal epidural plexus, thereby augmenting operative blood loss. While BMI has been studied as a predictor of spinal surgical outcomes, the differential impact of fat distribution pattern (central vs. peripheral obesity) on IAP dynamics and bleeding has not been adequately characterized.
Study Design:
Prospective, single-center, observational cohort study conducted at Marmara University Pendik Training and Research Hospital and Asaf Ataseven Hospital, Istanbul, Turkey. No interventions beyond routine clinical anesthesia practice will be performed.
Patient Groups:
Patients will be categorized into three groups based on BMI and waist-to-hip ratio (WHR):
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age 18-80 years
- •ASA Physical Status Classification I-III
- •Scheduled for elective major lumbar spinal surgery (canal stenosis decompression and/or instrumented fusion)
- •No prior lumbar spinal surgery
- •Written informed consent obtained
排除标准
- •- Pediatric patients (<18 years)
- •Pregnancy
- •Emergency surgical procedures
- •Pre-existing renal failure
- •Coagulation disorder
- •Pre-existing anemia
- •Known drug allergy relevant to study medications
- •Inability to obtain written informed consent
结局指标
主要结局
Intraoperative Blood Loss
时间窗: Intraoperative
Total estimated blood loss (mL) calculated from suction canister volume and surgical sponge weight.
Intraabdominal Pressure (IAP)
时间窗: Three intraoperative time points from beginning to end: 1.supine after intubation, 2.prone position, and 3.supine at end of surgery
Intravesical IAP measurement (mmHg) via urinary bladder catheter at positional transitions during surgery
次要结局
- Intraoperative Transfusion Requirement(Intraoperative)
- Postoperative Hemoglobin Drop(Within 24 hours postoperatively)
- Vasopressor/Inotrope Requirement(Intraoperative)
- Postoperative Transfusion Requirement(up to 7 days postoperatively)
- Postoperative ICU Admission Rate(postoperative day 1)
- Postoperative Surgical Complications(Up to 30 days postoperatively)
- Postoperative Medical Complications(Up to 30 days postoperatively)
- Hospital Length of Stay(From surgery to hospital discharge, assessed up to 30 days)
- Acute Kidney Injury Incidence(Time Frame: Within 24 hours postoperatively)