Comparative Study of the Change in Liver Enzymes After General or Spinal Anesthetic Techniques in Patients With Preoperatively Elevated Liver Enzymes.
Condition: Liver Enzymes After General or Spinal Anesthetic Techniques; In Patients With Preoperatively Elevated Liver Enzymes
Study type: Observational [Patient Registry]

Summary: 
      -  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.
    

Detailed description: 
      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
    

Intervention name(s): General anesthesia
Intervention type(s): Procedure
Intervention description(s): general anesthesia and regional anesthesia techniques are used
Other intervention name(s): Regional anesthesia
Intervention MeSH terms: Anesthetics
Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        60 Patients are randomly divided by computer designed lists and then concealed in closed
        envelopes into 2 equal groups:

          1. Group A(n=30),in which general anesthesia technique is used

          2. Group B(n=30),in which regional anesthesia technique is used
      
Biospecimen description: 
      Blood Samples Liver Enzymes measurments