DOI: 10.36347/sjams.2015.v03i05.017

Pages: 1891-1895

Regional blocks are often preferred to general anesthesia as they do not affect the body systemically and have the added benefit of providing extended pain relief with decreased use of analgesics. Vasoconstrictors are often added to local anesthetic (LA) solutions to prolong the block by reducing the clearance of the LA. This may help in reducing LA toxicity. Epinephrine has traditionally been the vasoconstrictor of choice. However, with both alpha and beta agonist properties, it may be problematic in patients taking beta-blockers. Phenylephrine, a pure alpha agonist, may be a better choice in these patients but has never been studied as an additive to las for upper extremity blocks. The primary objective of this study was to compare the efficacy (i.e., onset and duration of block) of epinephrine and two different concentrations of phenylephrine. The secondary objective was to study the side effects, if any, in each group.75 ASA I & II patients, above the age of 18, scheduled for elective operative shoulder arthroscopy under interscalene block with intravenous sedation were included in the study. These patients were randomly allocated to one of 3 groups. Group 1 received a standard LA mixture with 2.5 mcg/ml epinephrine. Group 2 received a standard LA mixture with 0.625 mcg/ml phenylephrine. Group 3 received a standard LA mixture with 1.25 mcg/ml. Phenylephrine. Onset and duration of block were recorded and analyzed. Recovery from the Block was assessed postoperatively in the PACU and via a phone call to the patient at home as Needed. Heart rates and blood pressures prior to block and for the first 30 minutes after the Initiation of the block was analyzed and compared.