Pathophysiology of Endovascular Resuscitation

<!-- type: physiology -->

Hemorrhagic shock produces progressive **oxygen debt** and a self-reinforcing cycle of hypoperfusion, acidosis, hypothermia, and coagulopathy (“lethal triad/lethal diamond”). Early hemorrhage control and **damage control resuscitation (DCR)** are therefore time-critical. [@rotondo1993] [@spahn2019]

**Where endovascular trauma management (EVTM) fits in DCR**

EVTM complements DCR by providing **rapid proximal or selective hemorrhage control** (e.g., resuscitative endovascular balloon occlusion of the aorta (REBOA), selective balloon occlusion, embolization, covered stents/stent-grafts) that can shorten time-to-hemostasis and reduce the duration of profound shock while definitive surgical/IRsurgical/interventional radiology (IR) control is arranged. [@morrison2014] [@trauma2016-endovascular] However, the clinical benefit of REBOA remains a subject of intense debate; recent evidence from the UK-REBOA randomized clinical trial (RCT) indicated that the addition of REBOA to standard care in the emergency department (ED) did not improve survival and may even increase mortality, potentially due to procedural delays or complications [@jansen2026].

**Physiologic principles of aortic balloon occlusion**

- **Complete occlusion (cREBOA):** maximizes proximal perfusion but risks severe distal ischemiaischemia, reperfusion injury, and reperfusionprocedural injury;complications such as vascular access site injury or arterial thrombosis; use the **shortest feasible occlusion time** and transition quickly to definitive control. [@bulger2019] [@marcelo2024]
- **Partial/intermittent REBOA (pREBOA/iREBOA):** titrated deflation can preserve some distal flow and attenuate metabolic burden compared with continuous complete occlusion, especially as a bridge when definitive hemostasis is not yet achieved. [@sadeghi2018-partial]

**Endovascular hemostasis and preservation of perfusion**

Covered stents and stent-grafts can **exclude arterial disruption while maintaining in-line flow**, which is particularly valuable for junctional vessels (subclavian/axillary/iliac) that are difficult to expose surgically in unstable patients. [@markov2011]

Embolization provides distal/branch control (e.g., pelvic arterial bleeding, solid organ injury) and is commonly integrated into pelvic hemorrhage pathways alongside packing and/or REBOA depending on physiology and resource availability. [@coccolini2017-wses]

For surgical damage control concepts (packing, abbreviated laparotomy, open abdomen strategy), see [[Damage Control Surgery]] and [[Open Abdomen]]. [@wses2018]