What is the importance of maintaining blood supply during bladder surgery?

Blood Supply Management During Bladder Surgery

Critical Importance of Maintaining Adequate Blood Supply

Maintaining normovolemia and adequate oxygen supply during bladder surgery is essential to prevent splanchnic hypoperfusion, which directly impacts anastomotic integrity, reduces postoperative complications, and improves overall surgical outcomes. 1

Intraoperative Blood Supply Optimization

Hemodynamic Management

• Maintain mean arterial pressure above 80 mmHg using controlled hypotension techniques with antifibrinolytics to limit blood loss while ensuring adequate tissue perfusion 1
• Avoid intraoperative hypotension as it negatively impacts gut and anastomotic perfusion, which is critical given the lack of vascular autoregulation in the splanchnic area 1
• Use vasopressors (neosynephrine or low-dose norepinephrine) appropriately to maintain adequate perfusion pressure 1

Fluid Management Strategy

• Aim for a mildly positive fluid balance of 1-2 liters by the end of surgery to maintain normovolemia and protect kidney function 1
• Implement goal-directed fluid therapy (GDFT) using minimally invasive cardiac output monitoring, particularly in ASA III-IV patients, to ensure adequate tissue perfusion 1
• Both fluid excess and hypovolemia can provoke splanchnic hypoperfusion, resulting in ileus and increased morbidity 1

Blood Loss Management

• Timely substitution of blood loss should occur when estimated blood loss exceeds 500 ml to maintain normovolemia 1
• However, exercise caution with blood transfusion: intraoperative transfusion is associated with increased perioperative morbidity and worsened survival outcomes in bladder cancer patients, particularly those receiving neoadjuvant chemotherapy 2
• Use a restrictive transfusion strategy when possible, as perioperative blood transfusion may cause transfusion-related immunomodulation 2

Oxygenation and Perfusion

Oxygen Delivery

• Maintain inspired oxygen concentration >80% to decrease surgical-site infection risk 1
• Prevent hypoxemia through adequate lung ventilation with low tidal volumes to limit peak airway pressure and reduce barotrauma risk 1
• Ensure adequate central and peripheral oxygenation throughout the procedure 1

Metabolic Control

• Maintain normoglycemia with blood glucose <10 mmol/L using intravenous insulin when needed, as hyperglycemia leads to postoperative complications 1
• Prevent hypothermia (<36°C), as prolonged abdominal cavity exposure and anesthesia can cause perioperative hypothermia that affects tissue perfusion 1

Anatomical Considerations

Bladder Vascular Supply

• Blood vessels in the bladder must lengthen and shorten during filling and emptying while maintaining sufficient smooth muscle perfusion 3
• Innervation and blood supply enter the bladder neck region on the dorsal surface, making this area particularly vulnerable during surgical manipulation 4
• Interruption of blood supply may result in ischemia and subsequent reperfusion injury, leading to bladder pathologies 3

Surgical Approach Implications

• When performing cystotomy, approach via the ventral surface to avoid disrupting the primary vascular supply entering dorsally at the bladder neck 4
• During partial cystectomy, preserve the trigone region to maintain vascular integrity and allow gradual return to near-normal function 4

Anesthetic Protocol for Blood Supply Maintenance

Multimodal Approach

• Use thoracic epidural analgesia (Th9-11) for its benefits in maintaining hemodynamic stability 1
• Minimize opioids to reduce their negative hemodynamic effects 1
• Employ short-acting anesthetic agents (remifentanil) to facilitate precise hemodynamic control 1

Common Pitfalls to Avoid

Fluid Management Errors

• Avoid both fluid overload and hypovolemia: either extreme can compromise splanchnic perfusion and anastomotic healing 1
• Do not rely solely on urine output for fluid monitoring in cystectomy patients, as it can be unreliable 1
• Recognize that "zero-balance" fluid strategies may increase acute kidney injury risk; a mildly positive balance is preferred 1

Transfusion-Related Issues

• Avoid unnecessary intraoperative transfusions, as they are specifically associated with decreased overall survival, cancer-specific survival, and increased morbidity in bladder cancer patients 2
• Distinguish between intraoperative and postoperative transfusion needs: intraoperative transfusion carries worse prognostic implications 2

Perfusion Monitoring

• In high-risk patients (ASA III-IV), implement dedicated individualized goal-directed fluid management by an experienced anesthetist rather than relying on standard protocols 1
• Consider esophageal Doppler guidance as a valuable adjunct for optimizing cardiac output and tissue perfusion 1