OBJECTIVES: Ketamine is a non-barbiturate agent with rapid action onset that induces profound sedation; however, some emergency physicians tend not to use ketamine because of the risk of emergence delirium (ED). This study aimed to evaluate the effectiveness of haloperidol prophylaxis in postoperative ketamine delirium in children. METHODS: Prospective data relating to any emergence dreams, delirium, hallucinations, agitation, crying, altered perceptions, and necessary interventions were recorded in consecutive cases of ketamine delirium in patients attending Mansoura University Hospital, Egypt, from June 2010 to May 2011. RESULTS: A total of 537 records were available for analysis. Of those, 267 received prophylactic haloperidol (49.7%). There were significant differences between the two groups regarding post-anaesthetic care unit behaviour. The ketamine-haloperidol groups included more patients who were sleepy, calm (P ≤0.01) and less irritable (P ≤0.01), with a lower incidence of crying (P ≤0.01) and disorientation (P ≤0.01). CONCLUSION: We found that preoperative administration of haloperidol decreases the incidence of postoperative delirium in a sample of Egyptian children undergoing minor surgery. This is congruent with earlier work conducted in adults. This work carries great hope to decrease and even prevent ED in hospitalised, non-surgical patients.
The anaesthetic ketamine is used to treat various chronic pain syndromes, especially those that have a neuropathic component. Low dose ketamine produces strong analgesia in neuropathic pain states, presumably by inhibition of the N-methyl-D-aspartate receptor although other mechanisms are possibly involved, including enhancement of descending inhibition and anti-inflammatory effects at central sites. Current data on short term infusions indicate that ketamine produces potent analgesia during administration only, while three studies on the effect of prolonged infusion (4-14 days) show long-term analgesic effects up to 3 months following infusion. The side effects of ketamine noted in clinical studies include psychedelic symptoms (hallucinations, memory defects, panic attacks), nausea/vomiting, somnolence, cardiovascular stimulation and, in a minority of patients, hepatoxicity. The recreational use of ketamineis increasing and comes with a variety of additional risks ranging from bladder and renal complications to persistent psychotypical behaviour and memory defects. Blind extrapolation of these risks to clinical patients is difficult because of the variable, high and recurrent exposure to the drug in ketamine abusers and the high frequency of abuse of other illicit substances in this population. In clinical settings, ketamine is well tolerated, especially when benzodiazepines are used to tame the psychotropic side effects. Irrespective, close monitoring of patients receiving ketamine is mandatory, particularly aimed at CNS, haemodynamic, renal and hepatic symptoms as well as abuse. Further research is required to assess whether the benefits outweigh the risks and costs. Until definite proof is obtained ketamine administration should be restricted to patients with therapy-resistant severe neuropathic pain.
Ketamine was originally synthesised for use as a dissociative anaesthetic, and it remains widely used legitimately for this indication. However, there is increasing evidence of non-medical recreational use of ketamine, particularly in individuals who frequent the night-time economy. The population-level and sub-population (clubbers) prevalence of recreational use of ketamine is not known but is likely to be similar, or slightly lower than, that of other recreational drugs such as cocaine, MDMA, and amphetamine. The predominant features of acute toxicity associated with the recreational use of ketamine are neuro-behavioural abnormalities such as agitation, hallucinations, anxiety, and psychosis. Secondary to these, individuals put themselves at greater risk of physical harm/trauma. Cardiovascular features (hypertension and tachycardia) occur less frequently and the risk of death from recreational use is low and is predominately due to the physical harm/trauma. Long-term recreational use of ketamine can be associated with the development of psychological dependence and tolerance. There are reports of gastro-intestinal toxicity, particularly abdominal pain and abnormal liver function tests, and of neuropsychiatric disorders, typically a schizophrenia-like syndrome, in long-term users. Finally, there are increasing reports of urological disorders, particularly haemorrhagic cystitis, associated with long-term use. The management of these problems associated with the long-term use of ketamine is largely supportive and abstinence from ongoing exposure to ketamine. In this review we will collate the available information on the epidemiology of recreational use of ketamine and describe the patterns of acute and chronic toxicity associated with its recreational use and the management of this toxicity.