- Low CVP anaesthesia in liver surgery or trauma is used to minimise blood loss during hepatic dissection or control of haemorrhage.
- Mechanism
- The liver has a dual blood supply (portal vein and hepatic artery) and is highly vascular
- The hepatic veins drain directly into the IVC and are thin-walled and prone to bleeding
- Lowering central venous pressure reduces backflow and venous congestion, especially in the hepatic veins and sinusoids
- This leads to less oozing from the cut surface during resection or packing
- Target CVP
- Aim for CVP of 0–5 mmHg, ideally closer to 3 or below during the bleeding control phase
- Methods to achieve low CVP
- Restrict IV fluids pre-dissection (fluid boluses delayed until after haemostasis)
- Use of diuretics or vasodilators in selected cases
- Controlled ventilation with PEEP minimised to avoid increasing intrathoracic pressure
- Reverse Trendelenburg positioning may help manipulate venous return
- Benefits
- Reduces intraoperative blood loss
- Improves visibility during hepatic dissection or packing
- May reduce transfusion requirements
https://www.apicareonline.com/index.php/APIC/article/view/378/1254