A patient with placenta accreta spectrum (PAS) disorder undergoes cesarean hysterectomy. Intraoperatively, bleeding is controlled with a balloon catheter in the internal iliac artery. The mechanism of hemostasis provided by this intervention is:

• A Permanent occlusion of the internal iliac artery reducing pulse pressure to distal vessels
• B Retrograde thrombosis propagating to uterine artery origins
• C Temporary reduction in pulse pressure allowing clot formation, while collateral flow prevents tissue necrosis ✓
• D Vasospasm of the uterine artery via balloon contact pressure

Explanation

Balloon occlusion of the internal iliac (hypogastric) artery works by temporarily reducing pulse pressure in the pelvic vessels, creating a low-flow state that promotes clot formation at surgical bleeding sites. Critically, the rich collateral circulation of the pelvis (via femoral circumflex, inferior gluteal, obturator arteries) prevents ischemic necrosis of pelvic organs. The occlusion is temporary and reversible; it is not designed to cause permanent thrombosis or vasospasm.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.