Hemodynamic and Inflammatory Management During Aortic Cross‑Clamping
Cross‑Clamp Duration and Organ Risk
- Cross‑clamp times longer than 30 minutes significantly increase the incidence of neurologic deficits, mesenteric ischemia, and renal injury. 1
- In thoraco‑abdominal aortic repairs, omission of organ‑protection measures when clamp time exceeds 30 minutes markedly raises postoperative morbidity. 1
Blood‑Pressure Targets During Clamping
- Maintaining a proximal mean arterial pressure of 90–100 mmHg throughout aortic cross‑clamping is recommended to support systemic perfusion. 1
- Keeping distal arterial pressure at ≥60 mmHg is advised to preserve adequate spinal‑cord blood flow. 1
Organ‑Protection Strategies for Thoraco‑Abdominal Repairs
- Use of left‑heart bypass should be considered for descending or thoraco‑abdominal aortic repairs to sustain distal organ perfusion. 1
- Cerebrospinal‑fluid drainage is essential to lower the risk of postoperative paraplegia. 1
Inflammatory and Cellular Responses Associated with Cardiopulmonary Bypass (CPB)
- CPB with ischemic arrest triggers the release of cytokines and chemokines that influence cellular homeostasis, thrombosis, and coagulation (American Heart Association). 2
- Oxidative stress together with adhesion of blood‑cell elements to the endothelium contributes to myocardial injury during CPB (American Heart Association). 2
- Neuroendocrine stress pathways are activated during CPB with ischemic arrest (American Heart Association). 2
- The magnitude of the systemic inflammatory response syndrome (SIRS) is greater with on‑pump (CPB) procedures compared with off‑pump techniques (American Heart Association). 2