Hyperthermia neuroleptic malignant syndrome

Intrathecal - Early symptoms of baclofen withdrawal may include return of baseline spasticity, pruritus, hypotension, and paresthesias. Some clinical characteristics of the advanced intrathecal baclofen withdrawal syndrome may resemble autonomic dysreflexia, infection (sepsis), malignant hyperthermia, neuroleptic-malignant syndrome, or other conditions associated with a hypermetabolic state or widespread rhabdomyolysis. 

Adverse effects include nausea, vomiting, heartburn, constipation, diarrhoea, agranulocytosis, eosinophilia, postural hypotension, tachycardia, angina, headache, sedation, dizziness, syncope, seizures, hyperthermia, neuroleptic malignant syndrome, weight gain and sexual dysfunction. May lead to myocarditis. 

Other sedative-hypnotic medications, such as barbiturates, may play a useful role in severe withdrawal from this group of drugs. For example, in a case series of GBL withdrawal, use of intravenous pentobarbital in the range of 1-2 mg/kg/hour lowered the total requirement for intravenous lorazepam (Sivilotti et al. 2001). Antipsychotic medications are often used to reduce psychotic agitation. However, because antipsychotic medications lower the seizure threshold and may contribute to loss of central control of temperature leading to hyperthermia or neuroleptic malignant syndrome (NMS), they are not indicated as first-line medications for GHB withdrawal delirium (Dyer and Roth 2001 McDaniel and Miotto 2001 Sharma et al. 2001). If anti-... 

The patient may be alert and oriented, withdrawn or lethargic, or have an acute brain syndrome. There is a high incidence of rhabdomyolysis and hyperthermia in PCP-induced catatonic syndrome. Some patients have the neuroleptic malignant syndrome or develop it after administration of haloperidol. 

The neuroleptic malignant syndrome is characterized by hyperthermia (temperature over 103 °F without evidence of infection), altered sensorium, muscle rigidity, and autonomic disturbances, usually profuse diaphoresis, hypersali vat ion, bronchorrhea, and urinary retention. 

Neuroleptic malignant syndrome is an acute iatrogenic condition caused by neuroleptics, characterized by tremor, catatonia, fluctuating consciousness, hyperthermia, and cardiovascular instability. It is relatively uncommon, occuring in 1-1.5% of patients but is fatal in 11-38%, most often due to cardiovascular collapse (Jahan et al. 1992). The pathogenesis of neuroleptic malignant syndrome is poorly understood, but it is believed to result from altered dopamine and serotonin transmission in the hypothalamus, spinal cord, and striatum. Treatment includes discontinuation of neuroleptics and administration of drugs that increase dopamine transmission bromocriptine or L-dopa (Jahan etal. 1992 Baldessarini 1996). 

Neuroleptic malignant syndrome (NMS) is a rare, medication-induced syndrome that may be due to dopamine receptor blockade in the basal ganglia. An altered level of consciousness, autonomic instability, hyperthermia, and severe muscular rigidity typically... 

A rare, but potentially fatal idiosyncratic adverse effect is neuroleptic malignant syndrome. This can occur with any antipsychotic drug. The symptoms are rigidity, hyperthermia, autonomic lability, and reduced level of consciousness. Massively elevated levels of creatinine kinase are usually found. Prior to 1984, the mortality rate was around 25% but improved early recognition has considerably reduced this. Management is cessation of antipsychotics, appropriate conservative measures and dantrolene if necessary for muscle rigidity. 

Neuroleptic malignant syndrome D2-blocking antipsychotics Acute severe parkinsonism hypertension, hyperthermia, normal or reduced bowel sounds, onset over 1-3 days Diphenhydramine (parenteral), cooling if temperature is very high, sedation with benzodiazepines... 

Antipsychotic drugs include the older phenothiazines and butyrophenones, as well as newer atypical drugs. All of these can cause CNS depression, seizures, and hypotension. Some can cause QT prolongation. The potent dopamine D2 blockers are also associated with parkinsonian-like movement disorders (dystonic reactions) and in rare cases with the neuroleptic malignant syndrome, characterized by "lead-pipe" rigidity, hyperthermia, and autonomic instability (see Chapter 29 Antipsychotic Agents Lithium). 

Keck PE Jr, Caroff SN, McElroy SL (1995) Neuroleptic malignant syndrome and malignant hyperthermia end of a controversy J Neuropsychiatry Clin Neurosci 7(2) 135-144... 

Anaesthesia in MH-susceptible patients is achieved safely with total intravenous anaesthesia using propofol and opioids. Dantrolene for intravenous use must be available in every surgical theatre. The relation of malignant hyperthermia syndrome with neuroleptic malignant syndrome (for which dantrolene may be used as adjunctive treatment, see p. 388) is uncertain. 

This is not the first report of similarities between the neuroleptic malignant syndrome and baclofen withdrawal (18,20,24). In addition, hyperthermia seems to be common in baclofen withdrawal (20). 

Ward A, Chaffman MO, Sorkin EM. Dantrolene. A review of its pharmacodynamic and pharmacokinetic properties and therapeutic use in malignant hyperthermia, the neuroleptic malignant syndrome and an update of its use in muscle spasticity. Drugs 1986 32(2) 130-68. 

Management of fulminant hypermetabolism of skeletal muscle because of malignant hyperthermia crisis. Treatment of neuroleptic malignant syndrome, relief induced pain in patients with muscular of exercise-dystrophy, treatment of flexor spasms... 

The principal manifestations of phenothiazine toxicity involve the CNS and cardiovascular system. Signs of CNS toxicity include sedation, coma, respiratory depression (uncommon), seizures, hypothermia or hyperthermia, and extrapyramidal movement disorders (acute dystonia, parkinsonism, akathisia, tardive dyskinesia, and neuroleptic malignant syndrome) the extrapyramidal symptoms result from an imbalance between inhibitory dopamine and... 

Neuroleptic malignant syndrome is a rare but potentially fatal adverse reaction to some anti-psychotic drugs and requires immediate withdrawal of the drug. Symptoms are hyperthermia, fluctuating level of consciousness, muscular rigidity and autonomic dysfunction and can last five to seven days after withdrawal of the drug. 

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