A Comparative study of Anaesthetic efficacy of 0.2% Ropivacaine alone and 0.2% Ropivacaine with Fentanyl 50 mics in Intravenous Regional Anaesthesia

INTRODUCTION: Intravenous regional anaesthesia is a method of producing analgesia and muscle relaxation of the distal part of a limb by intravenous local anaesthetic injection while circulation to the limb is occluded. Intravenous regional anaesthesia was discovered by August Bier, professor of surgery in berlin in 1908. To administer intravenous anaesthesia he occluded the circulation in a segment of the arm with two tourniquets and then injected a solution of 0.5% procaine into a vein in the isolated segment. This technique was revived by Holmes in 1963, who used lignocaine because it appeared to give more reliable anaesthesia than procaine. Currently, intravenous regional anaesthesia sometimes referred to as Bier’s block is regarded as one of the several alternative techniques for arm anaesthesia. Various drugs such as procaine, prilocaine, lignocaine, bupivacaine has been used in intravenous regional anaesthesia. Among these, lignocaine is the drug commonly used. As lignocaine does not have post tourniquet deflation analgesia other local anaesthetic dugs have been tried to improve the duration and post operative analgesia. A longer acting agent bupivacaine initially gained substantial popularity but was laden with potentially serious side effects. Bupivacaine has been identified as a fast-in, slow-out type of local anaesthetic that maintains high affinity and binds tightly to myocardial sodium receptors. Therefore, if high plasma concentrations of bupivacaine are achieved irreversible cardiac arrest may occur. The amide local anaesthetic ropivacaine is a pure -s- enantiomer and is structurally related to bupivacaine. The duration of effect of ropivacaine is almost similar to that of bupivacaine. Ropivacaine has been shown to result in less depression of the cardiac conduction system when compared with bupivacaine. Intravenous ropivacaine, compared with bupivacaine and lignocaine in several studies has less cardiac and central nervous system side effects but has achieved better surgical anaesthetic conditions. In an attempt to reduce the amount of local anaesthetic required or to improve the quality of the block or both, various additives such as opiods, muscle relaxants, alpha2 agonists have been tried in intravenous regional anaesthesia with various results. Among these fentanyl a synthetic opiod is used in this study along with ropivacaine. AIM OF THE STUDY: The aim of the study is to evaluate, 1. The anaesthetic effects of 0.2% ropivacaine, 2. To compare it with the addition of fentanyl 50 mics in intravenous regional anaesthesia. The anaesthetic efficacy regarding, 1. Onset of Sensory Block, 2. Onset of Motor Block, 3. Occurrence of Tourniquet Pain, 4. Duration of Post OP Analgesia, 5. Side effects, if any are noted and compared. MATERIALS AND METHODS: This study was conducted in 50 patients undergoing hand surgeries in KAPV Govt medical college hospital. After getting institutional ethical committee approval and after explaining the procedure in detail, informed consent obtained from every patient. The patients were assigned into two groups each containing 25 patients. GROUP 1: Patients in this group received 40 ml of 0.2 % ropivacaine. GROUP 2: Patients in this group received 40 ml of 0.2 % ropivacaine with fentanyl 50 mics. Selection of Patients: The patients selected for this study were of ASA I and II, undergoing elective hand surgeries where the expected duration is less than an hour. Exclusion Criteria: Patients with history of any cardiovascular, respiratory or central nervous system disorders were excluded from the study. Patients with haematological disorders like sickle cell anaemia and thalassemia, patients with known hypersensitivity to ropivacaine, patients with difficult airway, were also excluded from the study. SUMMARY: We conducted a randomised control study in 50 ASA I and II patients aged 19 to 60 for elective hand surgeries by intravenous regional anaesthetic technique at KAPV Govt medical college hospital, Trichy. This study was to evaluate the, 1. anaesthetic efficacy, 2. post tourniquet release analgesia, 3. side effects of ropivacaine 0.2% alone and to compare it with adding fentanyl 50 mics. The patients were divided into two groups namely group 1 and group 2. 1. Sensory block onset, 2. motor block onset, 3. incidence of tourniquet pain, 4. post tourniquet release analgesia, 5. side effects ,if any were evaluated. We found that fentanyl 50 mics when added with ropivacaine 0.2% in intravenous regional anaesthesia improved the anaesthetic efficacy, lengthened post tourniquet analgesia and reduced the incidence of tourniquet pain as compared to Ropivacaine alone, which has been proved statistically significant using quantitative and qualitative analysis. CONCLUSION: We conclude that ropivacaine 0.2% with fentanyl 50 mics in intravenous regional anaesthesia has good anaesthetic efficacy, lengthened post operative analgesia and less incidence of intra operativetourniquet pain with minimal alterations in hemodyanamics after tourniquet release when compared to ropivacaine 0.2% alone