A Comparative study of 150μg of Buprenorphine with 0.3% Bupivacaine and 0.3% Bupivacaine alone in Brachial Plexus Block by Low Interscalene Approach in Upper Limb Surgeries

Abstract

INTRODUCTION: Regional Anaesthesia is the blocking of peripheral nerve conduction in a reversible way by using local anesthetic agents, thereby one region of the body is made insensitive to pain and is devoid of reflex response to surgical stimuli. In this the CNS is spared, so that the patient is conscious, fully aware during the surgical procedure without recognizing pain. Regional Anaesthesia has many advantages over general anaesthesia for surgeries on upper extremities particularly in emergency surgeries. They are: (i) Proven to be the safest anaesthesia for high risk patients who are in greater risk due to stress imposed by general anaesthesia. (ii) Only method of anaesthesia which prevents all afferent impulses from the site of surgery reaching the CNS. Hence the need of poly pharmacy and its side effects are eliminated. (iii) Along with complete pain relief and total muscle relaxation it produces vasodilatation, which improve blood circulation, and prevents tissue hypoxia. (iv) Causes least disturbance to the normal physiology than any other type of anaesthesia. (v) Postoperative pain relief is ensured for a longer duration by using long acting anaesthetic drug and for several days if continuous block using catheter technique is employed. (vi) Many intra operative, postoperative complication of general anaesthesia are avoided. (vii) It is cost effective and safe. (viii) Avoids theatre pollution. (ix) Safest technique for patients with full stomach. The use of pneumatic tourniquet provides a bloodless field during upper extremity surgeries. The tourniquet pain is a concern because of the technical difficulty to block individual nerves. Brachial plexus block by supraclavicular approach is the solution in such a situation. There are different approaches for blocking brachial plexus, the common approaches are (a) Supraclavicular approach, (b) Interscalene approach, (c) Axillary approach, Axillary approach has the lowest incidence of serious complication and can be performed with ease. Still there is limitation associated with axillary approach like, • It is inadequate for operation on the arm and shoulder. • It is difficult to block the musculocutaneous nerve predictably with resultant sparing of the radial aspect of forearm and dorsum of hand. • Tourniquet pain is not well tolerated. • Also abducting the arm by 90° for giving the block may be painful and even dangerous in traumatic lesions of the upper extremities. Hence the brachial plexus block by low scalene approach is the method of choice for upper limb surgeries. In 1970 Alon Winne first demonstered interscalene approach of brachial block. William Steward Halsted first performed brachial plexus block in 1885. In 1911 Kulenkampff and Hirschel described the first percutanceous brachial plexus block by supraclavicular and axillary routes respectively. Since then several techniques have been used to prolong the brachial plexus block. • Continues infusion of local anaesthetic through catheters. • Addition of epinephrine and α2 agonist like clonidine. • Addition of opioids are being used as adjuvant to local anaesthetic solution e.g. Morphine, Buprenorphine and butorphanol. Buprenorphine, a thebaine derivative of semi synthetic opioid compound acts both on muopioids receptor and Kappa receptors. It is used for pain relief and this is given by intra muscular, intra venous, epidural and spinal routes and the dose in 0.3 to 0.6mg. It is many times more potent than morphine and it has side effects of nausea, vomiting, respiratory depression etc. This study compares the effects of addition of Buprenorphine to local anaethetic solution with plain local anaesthetic solution for brachial plexus block, with regard to onset, time for total blockade, duration and quality of blockade. AIM OF STUDY: The opioid receptors are found in the central nervous system. The presence of these receptors in the somatic and sympathetic peripheral nerves has also been documented. In this study an alternate is made to compare the effects of addition of buprenorphine to 0.3% bupivacaine versus 0.3% bupivacaine, and also to evaluate the action of buprenorphine on the peripheral nerve receptors in brachial plexus block. So, this is the study to 1. To compare the effects and actions of 0.3% bupivacaine and addition of 150μg buprenorphine to 0.3% bupivaccine in brachial plexus block by low interscalene approach. 2. To compare the onset, time taken for total blockade, duration and intensity of motor and sensory blockade. 3. To evaluate the action of opioid, buprenorphine on the peripheral nerves. MATERIAL AND METHODOLOGY: Forty adult patients of both sexes in the age group of 18 to 58 belonging to ASA I/II attending the Plastic & hand reconstructive surgery department at Stanley Medical College Hospital, Chennai-1 formed the material for the study. They were randomly divided into 2 groups I and II. Group I - 20 patients received 30 ml of 0.3% bupivacaine plus 1ml of isotonic sodium chloride solution making the solution 0.3%. Group II - 20 patients received 18ml of 0.5% bupivacaine plus 1ml of 150 microgram of buprenorphine. Patient selection: 1. Only ASA I & ASA II were included. 2. Age group between 18 to 58 years. 3. Weight between 40 to 70kg. 4. Both emergency and elective procedure involving the upper limb were included. 5. Both in patients and outpatients were included. Exclusion criteria: 1. Patient refusal, 2. Clinically significant coagulopathy bacterial, fungal infection the injection site, 3. Pneumothorax, 4. Known epileptic. SUMMARY: 1. Onset time of sensory and motor blockade is shorter in Group II than control Group I. 2. There was no difference in the time for total sensory and motor blockade in both the groups. 3. These was significant increase in the duration of blockade in the Group II than Group I. 4. There was significant increase in the intensity of sensory and motor blockade in the Group II than Group I. 5. There was no complication due to addition of 150 micrograms of buprenorphine to 0.3% bupivacaine. CONCLUSION: We conclude that in brachial plexus block by low interscalne approach, the addition of 150μg of buprenorphine with 0.3% bupivacaine provides intense, prolonged sensory and motor blockade without complication when it is compared to the block produced by plain 0.3% of bupivacaine solution alone