In Patients With Preoperatively Elevated Liver Enzymes Clinical Trial
Official title:
Comparative Study of the Change in Liver Enzymes After General or Spinal Anesthetic Techniques in Patients With Preoperatively Elevated Liver Enzymes
- To assess the changes in liver functions postoperatively in patients with preoperatively
elevated liver enzymes.
- To identify the most appropriate anesthesia technique for patients with preoperatively
elevated liver enzymes.
- To assess the effect of intraoperative event (bleeding, hypoxia, hypotension, prolonged
operation) on liver functions in these patients.
Surgery and anesthesia are stressful events, thus there is a possibility that liver enzymes
and bilirubin may increase postoperatively. Mild elevations of serum aminotransferase,
alkaline phosphatase, or bilirubin levels are frequent after surgical procedures, whether
performed under general or spinal anesthesia. Anesthesia causes an initial reduction in
hepatic arterial blood flow of 35-42% in the first 30 min of induction of anesthesia. During
surgery, The liver blood flow returns to baseline. It is possible that either the initial
hypoperfusion or reperfusion injury, or both, may contribute to postoperative liver
dysfunction when it occurs.
The type of surgery is potentially an important factor of postoperative hepatic dysfunction.
Intra-abdominal operations are more likely than extra-abdominal surgeries to cause reflex
systemic hypotension and to subsequently reduce hepatic blood flow.This could be due to
traction on abdominal viscera. Hypercarbia-induced splanchnic vasoconstriction is also a
threat to hepatic perfusion in laparoscopic surgery. Surgeries that result in a large amount
of blood loss increase the risk for ischemic hepatic injury, as can intraoperative
hypotension.
Liver disease is important to recognize preoperatively because the risk of surgery in
patients with advanced disease can be grave.Patients with liver disease are more likely than
patients without liver disease to experience hepatic decompensation with anesthesia.
Measurement of serum Bilirubin levels is central to the evaluation of hepatobiliary
disorders. Liver disease is a challenging condition for the anesthesiologist, However, the
risk could be diminished by careful consideration of the patients' condition preoperatively
and choosing suitable anesthetic procedure and drugs for these patients.Meanwhile, The effect
of performing spinal anesthesia on patients with liver disease has not been investigated
properly as most studies excluded patients with preoperatively elevated liver enzymes.
Studies on patients undergoing general anesthesia with normal preoperative liver function
tests showed a transient increase in the level of AST& ALT, with a mild increase in
postoperative bilirubin levels
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