Introduction

Spinal anaesthesia is the most commonly used technique for below umbilical surgeries. It is economical, easy to administer and relatively safer. It is important to limit the block level for minimizing hemodynamic changes during the spinal anesthesia in elderly and those with cardiopulmonary, endocrine and other comorbidities.

Low-dose local anesthetics can limit the block level and induce rapid recovery from anesthesia, but sometimes these low-dose local anesthetics may not provide an adequate anesthetic level for surgery. Intrathecal opioids or clonidine are frequently co-administered with local anesthetics to improve the anesthetic quality and postoperative analgesia.

The side effects of bupivacaine are dose dependent. This can be reduced by lowering it’s dose and use of adjuvants like fentanyl, clonidine, dexmedetomidine. Opioids used as adjuvants with local anaesthetics improve the quality and duration of post operative analgesia. It has beneficial effect of early ambulation because of minimal motor block. Use of lipophilic opiates have a favourable pharmacokinetic and pharmacodynamic profile. Morphine was the first opioid to be used intrathecally but side effects like delayed respiratory depression limited its utility.

Fentanyl being highly lipid soluble diffuses rapidly into spinal cord and binds to opioid receptors in dorsal horn when administered intrathecally. This produces rapid onset of analgesia with minimal cephalic spread. Hence the risk of delayed respiratory depression is less.

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Dr. Letha.J

Associate Professor, Department Of Anaesthesiology Govt. T.D Medical College, Alappuzha, India