Stroke Volume Variation Versus Central Venous Pressure Guidance for Reducing Perioperative Blood Loss During Open Liver Resection

Summary

Liver resection is a major surgery that can be associated with significant intraoperative blood loss and blood transfusion. Among high-volume centers, median intraoperative blood loss ranges between 300-800 ml. Excessive blood loss is a strong independent predictor of worsened postoperative outcomes, increasing morbidity and mortality rates by 20%-35%. Additionally, perioperative allogeneic blood transfusions are associated with deleterious outcomes, including tumor recurrence and increased rates of complications and death.

The liver is a highly vascular organ with minimal vascular resistance, receiving up to 25% of cardiac output and pooling 20% of the splanchnic blood. Hepatic veins are a common source of venous hemorrhage. The pressure in the hepatic veins is directly correlated with the pressure in the vena cava and reducing cardiac preload results in decreased hepatic vein congestion. Therefore, low central venous pressure anesthesia (typically below 5 mmHg) can reduce the pressure gradient for retrograde venous bleeding, facilitate the outflow of blood from hepatic veins, and decrease blood volume and pressure in the liver. This anesthetic method is the standard technique to minimize blood loss during liver resection.

Central venous pressure was the static parameter used to indicate the right ventricular end-diastolic volume index (RVEDI) and was believed to be correlated with volume status. Despite this, central venous pressure did not reliably predict preload responsiveness due to the curvilinear shape of the ventricular pressure-volume curve, which indicates a poor relationship between ventricular filling pressure and volume. Additionally, the placement of a central venous catheter could lead to serious complications such as arterial cannulation, pneumothorax, and infection.

Arterial waveform analysis is dynamic hemodynamic monitoring based on the interaction between the heart and lungs in patients with mechanical ventilation. Stroke volume variation (SVV) is one aspect of arterial pressure waveform analysis and is a less invasive alternative technique for guiding preload status and fluid management in patients undergoing major abdominal surgery.

In liver resection, several anesthetic methods are used to achieve low central venous pressure (CVP \< 5 mmHg) during the liver parenchymal dissection phase. These methods include intraoperative volume restriction, administration of venodilators or vasodilators, the use of forced diuresis with furosemide, and the implementation of hypovolemic phlebotomy. As mentioned, central venous pressure is a static hemodynamic monitoring parameter and poorly correlates with volume status. Recently, stroke volume variation has been recognized as a good parameter to predict volume status and fluid responsiveness in patients undergoing liver resection. However, no previous publications have studied the efficacy of stroke volume variation monitoring compared with central venous pressure monitoring to reduce perioperative blood loss during open liver resection.

The study aimed to compare the efficacy of maintaining high stroke volume variation versus low central venous pressure in reducing perioperative blood loss during the liver transection phase in open liver resection.

Conditions

• Liver Tumor; Surgery
• Primary Liver Tumor, Metastatic Liver
• Primary Liver Cancer
• Liver Resection
• Benign Liver Tumor

Interventions

DEVICE

High stroke volume variation group

Anesthesiologists will perform methods to achieve and maintain SVV at 13-20% during liver parenchymal transection (fluid restrictive phase). Central venous pressure monitoring will be concealed with drapes, and the room anesthesiologist will use SVV for guiding fluid management only during parenchymal transection phase. If SVV exceeds 20%, a balanced salt crystalloid will be administered in the minimal amount necessary to reduce the SVV to below 20%.

Sponsors & Collaborators

• Chiang Mai University

  collaborator OTHER

• Warangkana Lapisatepun

  lead OTHER

Principal Investigators

• Warangkana Lapisatepun, MD. PhD. · Chiang Mai University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

20 Years

Max Age

70 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-11-25

Primary Completion

2027-12-31

Completion

2028-06-30

Countries

• Thailand

Study Locations