David H. Gleason

A comparison of 0.5% bupivacaine, 0.5% ropivacaine, and 0.75% ropivacaine for interscalene brachial plexus block

The onset time and duration of action of ropivacaine during an interscalene block are not known.The potentially improved safety profile of ropivacaine may allow the use of higher concentrations to try and speed onset time. We compared bupivacaine and ropivacaine to determine the optimal long-acting local anesthetic and concentration for interscalene brachial plexus block. Seventy-five adult patients scheduled for outpatient shoulder surgery under interscalene block were entered into this double-blind, randomized study. Patients were assigned (n = 25 per group) to receive an interscalene block using 30 mL of 0.5% bupivacaine, 0.5% ropivacaine, or 0.75% ropivacaine. All solutions contained fresh epinephrine in a 1:400,000 concentration. At 1-min intervals after local anesthetic injection, patients were assessed to determine loss of shoulder abduction and loss of pinprick in the C5-6 dermatomes. Before discharge, patients were asked to document the time of first oral narcotic use, when incisional discomfort began, and when full sensation returned to the shoulder. The mean onset time of both motor and sensory blockade was <6 min in all groups. Duration of sensory blockade was similar in all groups as defined by the three recovery measures. We conclude that there is no clinically important difference in times to onset and recovery of interscalene block for bupivacaine 0.5%, ropivacaine 0.5%, and ropivacaine 0.75% when injected in equal volumes. Implications: In this study, we demonstrated a similar efficacy between equal concentrations of ropivacaine and bupivacaine. In addition, increasing the concentration of ropivacaine from 0.5% to 0.75% fails to improve the onset or duration of interscalene brachial plexus block. (Anesth Analg 1998;87:1316-9)

Paravertebral block for breast cancer surgery

PurposeMajor breast cancer surgery is associated with a high incidence of postoperative nausea, vomiting and pain. Regional anaesthesia, with intraoperative sedation, would seem an ideal alternative to general anaesthesia for this type of surgery. We report our initial experience using paravertebral blocks (PVB) to provide anaesthesia for major breast surgery.MethodsTwenty-five patients agreeing to have surgery performed under paravertebral blocks were studied. Procedures performed varied from simple lumpectomy with axillary dissection to modified radical mastectomy with axillary dissection. During monitored sedation, blocks opposite spinous processes of C7– T6 were performed using bupivacaine 0.5% with epinephrine, 3– 4 ml per segment. Patients were evaluated for 72 hr and were requested to document:(i) when sensation returned (ii) incidence and frequency of nausea or vomiting (iii) degree of discomfort and medication taken.ResultsTwenty patients had blocks that required no supplementation. Five patients had blocks that were incomplete. No complications were attributed to the blocks. Post-operatively, patients with successful blocks had minimal nausea, vomiting and pain. No patients found the procedure unsatisfactory. Patients with successful blocks were all very satisfied.ConclusionOur initial results show that PVB for breast cancer surgery can be successfully performed in a majority of patients with few side effects. All patients with successful blocks were returned to the ambulatory care unit, bypassing the recovery room. That breast cancer surgery under regional anaesthesia can be safely performed as an ambulatory procedure has the potential for accomplishing major cost-saving.RésuméObjectifLa chirurgie majeure du sein est associée à une incidence élevée de nausées, de vomissements et de douleurs postopératoires. L’anesthésie régionale avec sédation semblerait une solution de rechange idéale pour réaliser cette chirurgie. Les auteurs décrivent leur expérience initiale avec des blocs paravertébraux (BPV) pour l’anesthésie de la chirurgie mammaire majeure.MéthodesL’étude portait sur vingt-cinq patientes consentantes à une interventions sous blocs paravertébraux. Les interventions variaient de l’ablation d’une masse avec dissection axillaire à la mastectomie radicale modifée avec dissection axillaire. Pendant une sédation sous moniteur, des blocs étaient effectués latéralement aux apophyses épineuses de C7- T6 avec 3 à 4 ml de bupivacaine 0,5% adrénalinée par segment. Les patientes étaient évaluées pendant 72 h et on leur demandait de signaler: i) le moment du retour de la sensation ii) l’incidence et la fréquence des nausées ou des vomissements iii) le degré d’inconfort et la prise de médicaments.RésultatsVingt patientes sous bloc n’ont pas eu besoin d’analgésie supplémentaire. Pour cinq patientes le bloc était incomplet. Aucune complication n’était attribuable aux blocs. En postopératoire, les patientes aux blocs réussis avaient peu de nausées, de vomissements et de douleurs. Aucune des patientes ne s’est déclarée insatisfaite. Les patientes dont les blocs avaient réussi étaient toutes très satisfaites.ConclusionCes résultats initiaux montrent que les BPV réalisés pour une chirurgie mammaire peuvent fonctionner avec peu d’effets secondaires chez une majorité de patientes. Toutes les patientes chez qui les blocs avaient réussi sont retournées à l’unité des soins ambulatoires, sans arrêt à la salle de réveil. La chirurgie du cancer du sein peut être réalisée sous anesthésie régionale en toute sécurité en chirurgie ambulatoire et peut permettre de réaliser des économies importantes.

Major ambulatory surgery with continuous regional anesthesia and a disposable infusion pump

CONTINUOUS peripheral nerve blockade can provide prolonged postoperative analgesia. By infusing local anesthetic through a catheter, neural blockade can be achieved that lasts longer than a single-injection block. 1,2 Traditionally, this method of pain relief has required a cumbersome infusion pump and a hospital stay. Reconstructive surgery of the foot or ankle can result in severe postoperative pain that is difficult to treat. Frequently, patients having such procedures require large doses of intravenous narcotics, which make early hospital discharge difficult. By using an anesthetic method that can provide improved analgesia and obviate a prolonged hospital stay, ambulatory surgery may be facilitated. We describe two patients undergoing major ankle surgery. Both patients were discharged to their homes with a continuous Sciatic nerve block and a disposable infusion pump.