Segmental Epidural Anesthesia (SEA) V/S General Anesthesia for PCNL (AnesthesiaPCNL)

Comparative Evaluation of General Anesthesia (SEA) Using 0.5% Bupivacaine and Segmental Epidural Anesthesia (GA) for Percutaneous Nephro Lithotomy - A Retrospective Analysis

Management of nephrolithiasis has been revolutionized by the advent of shock-wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL). PCNL is a minimally invasive endoscopic technique and is used for the fragmentation and removal of stones of size more than 20 to 30 mm, staghorn stones or multiple stones resistant to ESWL. Anaesthesia for PCNL is a challenge because of the disease, surgical procedure, positioning, hypothermia,and the possibility of fluid absorption, dilutional anaemia and blood loss. General anaesthesia is the gold standard for this surgery.The advent of new drugs has refined the technique of general anaesthesia. However there are several issues related to prone position still to be addressed like accidental extubation and difficult reintubation, nerve injuries and post operative respiratory complications. Combined spinal epidural(CSE) and only epidural anaesthesia (EA) is a well established technique of anaesthesia for upper abdomen and lower thoracic surgeries. It use has also been reported in PCNL surgeries.Segmental epidural can selectively blocks pain fibres from the surgical site. This not only allows to limit the dose of the local anaesthetics, but also limit motor and sympathetic blockade. Selective sympathetic block is associated with respiratory, cardiac, gastrointestinal and metabolic benefits. This formed the basis of our current study. In the present study the investigators aimed to evaluate the efficacy of segmental epidural for PCNL and compared it with standard technique i.e. GA.

To evaluate efficacy the investigators compared intraoperative haemodynamics, surgical clearance of stones, post operative pain, surgeon's and Patient's satisfaction scores and postoperative complications and side effects in 60 ASA I and II patients undergoing PCNL surgery who received either General anesthesia or Segmental epidural Anesthesia.

Patients were premedicated with Inj. Atropine 0.06 mg intramuscularly half an hour prior to surgery, IV ranitidine 1mg kg-1, IV ondansetron 0.08mg kg-1 IV midazolam 0.02mg kg-1 and Pentazocine 0.3 mg/kg. Anaesthesia was induced with IV Thiopentone sodium 3-5 mg kg-1 and Vecuronium 0.1mg kg-1.and then intubated. Anaesthesia was maintained on 50 %:50% nitrous oxide and oxygen, vecuronium and propofol infusion . At the end of the surgery postoperative analgesia was given with IV tarmadol and local nfiltration with 0.25% bupivacaine at the surgical site. Patients were reversed with IV glycopyrrolate 0.008mg kg-1 and IV neostigmine 0.06mg kg-1 and extubated.

epidural space was located at T12 -L1 or L1-L2 space .The epidural catheter was inserted cephalad 5 cm upwards in the epidural space (tip approximately at T8 to T9). and test dose of 3 ml of 2% Adrenalized Lignocaine was administered..loading dose of 0.5% Bupivacaine, approximately 8 to 10 ml was injected epidurally with regular negative aspiration to block T6- T12 segments, if desired level was not achieved then additional dose of 1 to 1.5 ml 0.5% bupivacaine per spared segment was given to achieve the desired level.Motor blockade of the lower limbs was checked and noted before lithotomy, before prone and at the end of the surgery using Bromage scale. After two segment regression of sensory level epidural top up with 1/4th of initial dose 2 to 3 ml of 0.5% Bupivacaine was given. At the end of the surgery 8ml of 0.125% Bupivacaine was administered for postoperative analgesia and the catheter was removed.

Hemodynamic parameters Change in Mean Arterial Pressure in mm Hg Every 15 minutes for 2 hours and then every hourly till 24 hours

Inclusion Criteria: ASA I/II Age - 18 years to 60 years Either sex BMI < 30 Exclusion Criteria: Unwilling for consent ASA 3 Obesity with BMI > 30. Contraindications for Epidural Anaesthesia Undilated pelvicalyceal system