INTRODUCTION
Subarachnoid block is excellent anaesthetic technique in this modern era with high success rate and good safety profile. There is always search for a drug which is safe, efficacious and less toxic. Ropivacaine is one of the new drug which has relatively safer drug due its lower toxic profile from number of studies emerging a alternative drug for bupivacaine.
WHY ROPIVACAINE??
Spinal anaesthesia is a safe, economical and effective technique which provides reliable and rapid anesthesia with muscle relaxation for patients undergoing lower abdominal surgeries. Bupivacaine, an amino amide compound, is a 50:50 racemic mixture of S- and R- enantiomers, was synthesised and introduced into the clinical practice in 1963 and proved to be a very effective long acting local anaesthetic agent and commonly used for spinal anesthesia as hyperbaric solution. The major concern about the bupivacaine is the cardiotoxicity and neuro toxicity. The cardiotoxicity is because of R isomer has greater affinity for time gated sodium channel and binds to it. These concerns lead to the development of Ropivacaine, a new amino- amide local anaesthetic agent is similar in chemical structure to bupivacaine, which was introduced in India in 2009.
Ropivacaine is identical to bupivacaine ( pure S- enantiomer) in onset, quality and duration of sensory block but it produces lesser duration of motor blockade, has a better safety profile. This will be helpful for short duration of surgeries and for early ambulation comparing to bupivacaine.
The purpose of this study is to evaluate onset and duration of anesthesia, perioperative hemodynamic and any adverse effects, hyperbaric ropivacaine to hyperbaric bupivacaine in spinal anaesthesia in infra-umbilical surgeries.
PROS AND CONS OF ROPIVACAINE
PROS: | CONS: |
Greater selectivity for sensory blockade Shorter motor block – early recovery Less lipid soluble Less cardiotoxic Less neurotoxic |
Motor block
|
OBJECTIVES OF THE STUDY
Aim
Aim of the study is to determine the efficacy of 0.75% hyperbaric ropivacaine versus 0.5% hyperbaric bupivacaine for level, onset, duration of sensory and motor blockade of spinal anesthesia, hemodynamic changes in patient undergoing infra umbilical surgeries.
Primary objective
Primarily we observe the comparison of onset of motor and sensory blockade in spinal anaesthesia and hemodynamic changes.
Secondary objective
As secondary outcome we observe duration of motor and sensory blockade.
REVIEW OF LITERATURE
Tadeusz kasa et al conducted study in 75 people comparing 0.75% hyperbaric ropivacaine and 0.5% hyperbaric bupivacaine for elective caesarean section and studied about the hemodynamic changes, quality of the block, spread and regression were assessed and concluded that the hemodynamic parameters and respiratory function were similar in both groups. No difference in the quality of the blockade, spread and regression were similar in both groups.
Nazima menon et al did a comparative study with 0.75 hyperbaric ropivacaine and 0.5% hyperbaric bupivacaine in spinal anaesthesia for caesarean section, 60 parturients belonging to ASA I and II taken for study and block parameters like onset of sensory and motor blockade and duration of the block and hemodynamic changes were studied and concluded that onset of sensory and motor blockade is earlier in bupivacaine group and duration of the blockade was more in bupivacaine group compared to ropivacaine.
Hyperbaric ropivacaine has increased margin of safety with less alteration in hemodynamic changes as compared with hyperbaric bupivacaine.
Zekiye Bigat et al did a comparison of hyperbaric ropivacaine and hyperbaric bupivacaine in unilateral spinal anaesthesia for outpatient knee arthroscopy. Forty patients of ASA I and II were selected and divided into two groups and quality of spinal block, adverse effect and recovery times were recorded. It was concluded that hyperbaric ropivacaine is preferred over hyperbaric bupivacaine as it provides more selective unilateral block and faster recovery.
Ankur khandelwal et al did a prospective study using hyperbaric ropivacaine intrathecally in ASA I,II in day care procedures and studied about duration of motor and sensory blockade, onset of blockade and concluded that intrathecal hyperbaric ropivacaine is sufficient to produce anaesthesia for daycare surgeries.
REFERENCE
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- Clarkson CW, Hondeghem LM. Mechanism for bupivacaine depression of cardiac conduction: Fast block of sodium channels during the action potential with slow recovery from block during diastole. Anesthesiology 1985;62:396-405.
- Akerman B, Hellberg IB, Trossvik C. Primary evaluation of the local anaesthetic properties of the amino amide agent ropivacaine (LEA 103). Acta Anaesthesiol Scand 1988;32:571-8.
- McClure Ropivacaine. Br J Anaesth 1996;76:300-7.
- McConachie I, McGeachie J, Barrie J. Regional anesthetic techniques. In: Healy TEJ,Knight PR, eds. Wylie and Churchill Davidson’s A Practice of 7th ed. London: Arnold; 2003: 599-626