Impact of General Versus Regional Anesthesia on the Incidence of Postoperative Pulmonary Complications in Peripheral Arterial Surgery: a Multicenter Randomized Clinical Trial
试验速览
- 阶段
- 不适用
- 状态
- 尚未招募
- 入组人数
- 594
- 试验地点
- 1
- 主要终点
- Incidence of Postoperative Pulmonary Complications
研究概览
简要总结
This multicenter, prospective, randomized clinical trial aims to compare the effects of spinal (neuraxial) anesthesia with spontaneous ventilation versus general anesthesia with mechanical ventilation on the incidence of postoperative pulmonary complications in adult patients undergoing elective lower limb revascularization surgery. A total of 594 patients with symptomatic peripheral arterial disease will be randomly assigned to receive either spinal anesthesia with sedation or general anesthesia with mechanical ventilation. The primary outcome is the incidence of postoperative pulmonary complications within 30 days or until hospital discharge, including pneumonia, respiratory failure, pleural effusion, atelectasis, and other defined respiratory events. Secondary outcomes include cardiovascular events, hemodynamic instability, renal injury, delirium, extrapulmonary complications, adverse events in the operated limb, ICU and hospital length of stay, and mortality. The study will be conducted at Hospital de Clínicas de Porto Alegre, Hospital Nossa Senhora da Conceição, and other participating Brazilian centers, with an expected start date in July 2025 and completion in December 2029.
详细描述
This is a prospective, randomized, multicenter clinical trial designed to evaluate the impact of the anesthetic technique-general anesthesia with mechanical ventilation versus spinal (neuraxial) anesthesia with spontaneous ventilation-on the incidence of postoperative pulmonary complications in patients undergoing elective peripheral arterial revascularization surgery. The study population will include 594 adult patients (ASA II-IV) with symptomatic critical limb ischemia, scheduled for elective lower limb revascularization at tertiary hospitals in Brazil. Patients will be randomized into two groups: Group 1 will receive spinal anesthesia with intravenous sedation and supplemental nasal oxygen; Group 2 will receive general anesthesia with controlled mechanical ventilation using lung-protective strategies (tidal volume 6-8 mL/kg and PEEP 5 cmH₂O).
The primary outcome is the incidence of postoperative pulmonary complications within 30 days after surgery or until hospital discharge. These include pneumonia, respiratory failure, pleural effusion, atelectasis, pneumothorax, aspiration pneumonitis, bronchospasm, ARDS, pulmonary embolism, and exacerbation of preexisting respiratory disease, defined according to internationally recognized criteria.
Secondary outcomes include:
- major cardiovascular complications (nonfatal myocardial infarction, acute coronary syndrome, cardiogenic shock);
- hemodynamic complications (prolonged hypotension or distributive shock requiring vasopressors);
- other extrapulmonary complications such as acute kidney injury, stroke, delirium, sepsis, surgical limb complications (e.g., graft thrombosis, amputation), and thromboembolic events (e.g., DVT, PE);
- ICU and hospital length of stay, PACU time, and 30-day or in-hospital mortality.
Data collection will include perioperative gasometric evaluation, detailed intraoperative hemodynamic and ventilatory monitoring, analgesia and antiemetic usage, and adverse events tracking through predefined time points (intraoperative, immediate postoperative, and up to 30 days after surgery). Sample size calculation is based on detecting a reduction in pulmonary complications from 25% in the general anesthesia group to 15% in the spinal anesthesia group, with a power of 80% and a two-tailed alpha of 0.05. Randomization will be performed using computer-generated block sequences, and outcome assessors and statisticians will be blinded. The statistical analysis will follow the intention-to-treat principle and include regression modeling to control for potential confounders such as comorbidities and operative duration.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Double (Investigator, Outcomes Assessor)
盲法说明
Single-blinded (Outcomes Assessor)
Participants and anesthesiologists will not be blinded due to the nature of the interventions (general vs. spinal anesthesia).
However, postoperative outcome assessors and statisticians performing data analysis will be blinded to group allocation to reduce detection and assessment bias.
Randomization will be performed using a computer-generated block sequence and managed via the REDCap platform. Allocation concealment will be maintained using sealed envelopes.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Adults aged ≥18 years
- •ASA physical status II to IV
- •Scheduled for elective peripheral arterial revascularization of the lower limbs
- •Diagnosis of symptomatic peripheral arterial disease with critical limb ischemia
- •Able and willing to provide informed consent
排除标准
- •Body mass index (BMI) > 40 kg/m²
- •Emergency vascular surgery
- •History of lung resection surgery
- •Persistent hemodynamic instability preoperatively
- •History of bronchial asthma or chronic corticosteroid therapy
- •History of neuromuscular disorders
- •Current use of anticoagulants or antiplatelet agents contraindicating spinal anesthesia
- •Contraindications to spinal anesthesia (e.g., patient refusal, infection at puncture site, increased intracranial pressure, inability to cooperate due to agitation or cognitive impairment)
- •Acute vascular obstruction or other vascular complications not consistent with elective revascularization
研究组 & 干预措施
Spinal Anesthesia
Patients in this group will receive spinal (neuraxial) anesthesia with isobaric bupivacaine (15-20 mg) and intrathecal morphine (100 μg), with optional clonidine as an adjuvant. Sedation may be provided with intravenous midazolam, fentanyl, and/or propofol, as per anesthesiologist discretion. Supplemental oxygen will be administered via nasal cannula. Patients will breathe spontaneously and will not be mechanically ventilated.
干预措施: Spinal Anesthesia (Procedure)
General Anesthesia
Patients in this group will receive general anesthesia with intravenous induction (propofol or etomidate), opioids (remifentanil), and neuromuscular blockade (rocuronium), followed by endotracheal intubation and mechanical ventilation using a protective strategy (tidal volume 6-8 mL/kg predicted body weight and PEEP 5 cmH₂O). Anesthesia maintenance will include inhaled sevoflurane and continuous opioid infusion.
干预措施: General Anesthesia (Procedure)
结局指标
主要结局
Incidence of Postoperative Pulmonary Complications
时间窗: Up to 30 days after surgery.
Composite incidence of pulmonary complications occurring within 30 days after surgery or until hospital discharge. Events include: pneumonia, respiratory failure, pleural effusion, atelectasis, bronchospasm, aspiration pneumonitis, pneumothorax, pulmonary embolism, exacerbation of preexisting pulmonary disease, tracheobronchitis, and acute respiratory distress syndrome (ARDS), defined according to CDC and Berlin criteria.
次要结局
- Length of Stay in Post-Anesthesia Care Unit (PACU)(Up to 30 days after surgery.)
- Incidence of Major Cardiovascular Complications(Up to 30 days after surgery.)
- Incidence of Hemodynamic Complications(Up to 24 hours after surgery.)
- Incidence of Extrapulmonary Complications(Up to 30 days after surgery.)
- 30-Day Mortality(Up to 30 days after surgery.)