A comparative study of 0.5% bupivacaine with fentanyl versus 0.75% ropivacaine with fentanyl in epidural anesthesia for abdominal hysterectomy

A COMPARATIVE STUDY OF 0.5 % BUPIVACAINE WITH FENTANYL VERSUS0.75% ROPIVACAINE WITH FENTANYL IN EPIDURAL ANAESTHESIA FORABDOMINAL HYSTERECTOMY

Objectives:

1. To compare the onset of motor and sensory block.
2. To find out the duration of the sensory and motor blockade.
3. To observe intraoperative hemodynamic changes and assess post-operative analgesia

requirements in 24 hour. 4. To find out the duration of analgesia assessed by requirement of first rescue analgesic. 5. To observe any untoward incident during intraoperative and post-operative period andmanaged accordingly

Methods:

All sensory and motor assessments were made at 0,2,4,6,8,10,12,15,20,25 and 30 min andthen every 15 min until the block was regressed completely unless sedation, anesthesia, or surgeryprevented assessment. A single observer performed all assessments. Assessments of parameters include:

1. Onset of sensory block ( time from epidural injection to the occurrence of sensory block atdermatome level T6)
2. Duration of sensory block (time for two segment regression).
3. Onset of motor block (time from completion of epidural injection to the time when

Bromage grade 0 changed to grade 1) 4. Duration of motor block was assessed every 30min using Modified Bromage scale and

RAM (rectus abdominis muscle) test.76 5. Duration of analgesia (time for rescue analgesia) 6. Hemodynamic changes - heart rate, blood pressure, respiratory rate and pulse oximetry

saturation on every 5 minutes for first 30 minutes and thereafter measurement has beentaken for every 10 minutes till the end of surgery.

7. Obvious side effects – nausea and vomiting, hypotension, pruritus, retention of urine,respiratory depression. Sedation by fentanyl was assessed by modified Ramsay sedation score.

Modified Ramsay sedation score:

Score Clinical response

0. 0  Paralyzed, unable to evaluate
1. 1  Awake
2. 2  Lightly Sedated
3. 3  Moderately sedated, follows simple commands
4. 4  Deeply sedated, responds to non-painful stimuli
5. 5  Deeply sedated, responds only to painful stimuli
6. 6  Deeply sedated, unresponsive to painful stimuli

All patients received balanced salt solution.

Bradycardia, defined as heart rate (HR) <50/min, was managed by Inj. Atropine 0.6mg IV

bolus (may require repeatation). It was aimed to maintain the MAP between 65 and 85 mm Hg.Hypotension, defined by decrease in mean arterial blood pressure more than 20% below baselineor in normotensive patients, fall in systolic pressure below 90 mm Hg was treated with IVcrystalloid fluid bolus and subsequently IV phrenylephrine and IV mephentermine bolus (titratedto patient response) as necessary. Persistent hypotension was treated with a bolus of 100-200mlcrystalloids and maximally infused three boluses per hour according to clinical situation.

Analgesia was assessed by VAS pain score which is a linear pain scoring tool ranging from0 to 100 mm where 0 means no pain and 100 means worst possible pain.

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Rescue analgesia was administered postoperatively in the form of 8ml of either 0.125%solution of racemic bupivacaine or 0.2% ropivacaine respectively in group B and group R whenVAS score > 40 or patient requested for analgesia.

Timing of first rescue analgesia and total analgesic doses within first 24 hours were noted.Analgesia was assessed by a trained research assistant with the visual analogue pain score(VAS), at rest and at coughing. Post-operatively VAS was noted two hourly till 24 hour of surgery.Top-up rescue drug (epidural local anesthetic) was given if patients complained of pain or when

VAS score was >40.