Variation in spread of analgesia and loss of temperature discrimination during intermittent postoperative epidural bupivacaine administration.
The proximal-distal and bilateral extent of analgesia and loss of temperature discrimination were assessed during the initial 34.5 h after major abdominal surgery in ten patients receiving intermittent epidural bupivacaine injections according to a fixed dose regimen. Segmental spread of loss of temperature discrimination was invariably larger than analgesia at all times. During the later postoperative period (24-34 h) a pronounced intra-individual variation in both proximal-distal and bilateral spread of analgesia was observed despite identical epidural injections of bupivacaine. This variation in extent of analgesia was observed during injections of both 0.5% and 0.25% bupivacaine. The explanation of this observation is unknown but it may be shifts in catheter position, a variable disposition of the local anaesthetic agent or changes in the epidural space rather than tachyphylaxis.
D000368:Aged; D000698:Analgesia; D002045:Bupivacaine / Q000008:administration & dosage* / Q000494:pharmacology; D004824:Epidural Space; D005260:Female; D006801:Humans; D007267:Injections; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D013697:Thermosensing / Q000187:drug effects*
D002045:Bupivacaine