1/5. Postoperative delirium indicating an adverse drug interaction involving the selective serotonin reuptake inhibitor, paroxetine?We report a postoperative delirium expressed by a 49-year-old female patient during recovery from anaesthesia. Prominent features of the delirium, which lasted for nearly 2 days, included agitation, confusion, uncontrolled limb movements, abnormal ocular function, hypertension, pyrexia, brisk reflexes, ankle clonus and raised creatine kinase. The delirium did not respond to naloxone, diazepam or flumazenil. The patient had not been prescribed neuroleptics but, before surgery, she had been taking the selective serotonin reuptake inhibitor, paroxetine, to relieve her depression. During surgery, she was given morphine, which increases release of the neurotransmitter, serotonin, and ondansetron, which blunts neuronal release of dopamine. Although there is no clear explanation for the delirium, it had many features in common with problems associated with paroxetine withdrawal, the serotonin syndrome and the malignant neuroleptic syndrome. We offer several alternative explanations for this event, all of which rest on disruption of serotonergic and/or dopaminergic transmission and which could also involve inhibition by paroxetine of the P450 enzyme, CYP2D6, which metabolizes ondansetron.- - - - - - - - - - ranking = 1keywords = anaesthesia (Clic here for more details about this article) |
2/5. Serendipitous rapid detoxification from opiates: the importance of time-dependent processes.Opiate detoxification procedures aim to reduce intensity and duration of withdrawal. Ultra-rapid opiate detoxification (UROD) methods attempt to obtain this goal by administering naltrexone under deep sedation or anaesthesia. We present a case study on accidental ingestion of naltrexone in a methadone maintenance patient, which shows close methodological similarities with UROD procedures. naltrexone was effective in reducing withdrawal duration, but not as much as UROD studies report. The administration of naloxone after detoxification did not trigger withdrawal symptoms, even in the presence of methadone, as detected by urinalyses. These results suggest the importance of further developing detoxification methods based on protocols of administration of antagonists different from UROD, in absence of anaesthesia.- - - - - - - - - - ranking = 2keywords = anaesthesia (Clic here for more details about this article) |
3/5. Intraoperative high-dose remifentanil in a patient on naltrexone therapy.naltrexone hydrochloride is a synthetic opioid receptor antagonist recently used in efforts to provide rapid opioid detoxification. Other clinical uses include alleviating itch due to cholestasis or uraemia. We report a case where unrecognised naltrexone therapy for itch affected anaesthesia, resulting in high opioid requirements. We also discuss other analgesic options utilized.- - - - - - - - - - ranking = 1keywords = anaesthesia (Clic here for more details about this article) |
4/5. Effect of innappropriate naltrexone use in a heroin misuser.naltrexone is a long acting opioid receptor antagonist used in controlled opioid withdrawal drug programmes. When taken by an opioid dependent patient an acute withdrawal reaction will be precipitated. The case is presented where a known opioid drug misuser inadvertently ingested naltrexone in conjunction with heroin resulting in severe agitation, requiring heavy sedation followed by general anaesthesia to enable investigation and management of his clinical condition.- - - - - - - - - - ranking = 1keywords = anaesthesia (Clic here for more details about this article) |
5/5. Rebound hypertension during anaesthesia.A case of rebound hypertension under anaesthesia, following withdrawal of clonidine, is described and methods of treatment outlined.- - - - - - - - - - ranking = 5keywords = anaesthesia (Clic here for more details about this article) |