EditorWe read with great interest the article by Dal and colleagues1 on the efficacy of prophylactic ketamine in preventing postoperative shivering. We have observed this technique as very effective and useful in the postoperative setting. We wish to report another incidental finding which we observed in two patients in whom we used ketamine 0.5 mg kg1 for treatment of postoperative shivering.
Two adult female patients who had undergone upper abdominal surgery, had shivering on arrival in the post-anaesthesia care unit. Both patients had a urinary catheter that had been in place before commencement of surgery and complained of urinary catheter-related bladder discomfort. These patients were administered i.v. ketamine 0.5 mg kg1 as treatment for their shivering. Marked reduction in postoperative shivering was observed in both patients. To our surprise there was also marked reduction in the urinary catheter-related bladder discomfort in both these patients. We presume that ketamine might be effective in reducing catheter-related bladder discomfort by inhibition of the cholinergic system, which supplies to trigone of the urinary bladder.2 Further work is needed to evaluate this action of ketamine.
India
References
1 Dal D, Kose A, Honca M, Akinci SB, Basgul E, Aypar U. Efficacy of prophylactic ketamine in preventing postoperative shivering. Br J Anaesth 2005; 95: 18992
2 Durieux ME. Inhibition by ketamine of muscarinic acetylcholine receptor function. Anaesth Analg 1995; 81: 5762[Abstract]