Management of hyperpyrexia

Management of hyperpyrexia

1. Management of Hyperpyrexia Lt Dhirendra

2. Hyperpyrexia Also called Fever represents an elevation in the body's set thermoregulatory point Core temperature is regulated by the anterior hypothalamus Fever is caused by increased prostaglandin E 2 (PGE 2 ) synthesis in the hypothalamus

3. Autonomic discharge from hypothalamus raises core temperature through shivering and dermal vasoconstriction Normal circadian variation in core temperature occurs with nadir in early morning and peak in late afternoon Normal Body Temperature Upto 98.9 at 6 am Upto 99.9 at 4 pm

4. Etiology infectious process Drugs Antiarrhythmics (procainamide, quinidine) Antibiotics ( penicillins , sulfonamides , erythromycin, isoniazid, nitrofurantoin ) Anticonvulsants (barbiturates, carbamazepine, phenytoin) Antidepressants (TCAs, monoamine oxidase inhibitors) Antihistamines (H 1 and H 2 antagonists) Antihypertensives ( nifedipine , hydralazine, methyldopa, captopril, hydrochlorothiazide) Drugs of abuse (cocaine, amphetamines) NSAIDs Others (allopurinol, heparin, meperidine )

5. Systemic inflammatory Collagen vascular diseases Rheumatic fever Rheumatoid arthritis Systemic lupus erythematosus Vasculitis Polymyalgia rheumatica Temporal arteritis Granulomatous diseases Sarcoidosis Inflammatory bowel disease Sickle cell disease Hemolytic anemia

6. Neoplastic disease Lymphomas and leukemias Hepatoma Metastatic carcinomas Atrial myxomas Endocrine Lymphomas and leukemias Hepatoma Metastatic carcinomas Atrial myxomas Pulmonary embolus Familial Mediterranean fever CNS lesions

7. Signs and Symptoms Chills, shivering, and rigors Mechanisms to raise body core temperature Fatigue Malaise Myalgias Night sweats Anorexia

8. Specific fever patterns Relapsing fevers: febrile episode with alternating afebrile intervals Seen in malaria, Borrelia infections, rat-bite fever, and lymphoma ( Pel Ebstein fevers) Remittent fever: temperature falls daily but does not return to normal Seen in TB and viral diseases Intermittent fevers: exaggerated circadian rhythm Seen in systemic infections, malignancy, and drug fever Reversal of normal circadian patterns Sometimes seen in typhoid fever and disseminated TB

9. Differential Diagnosis Core temperatures >41°C more common in these states Neuroleptic malignant syndrome Malignant hyperthermia Serotonin syndrome Heat stroke

10. Treatment Monitoring and IV access should be obtained in the field for unstable patients or patients with altered mental status Immediate treatment rarely required Airway control, breathing and circulatory support for unstable patients Initiate broad-spectrum antibiotic treatment immediately for immunocompromised patients and patients with unstable vital signs or profound mental status changes

11. Antipyretics Acetaminophen, NSAIDs, or salicylates Glucocorticoids Most febrile patients do not require antipyretic medication other than for comfort. Selected patients require more aggressive antipyretic interventions Pregnant women Patients with history of seizure disorders Patients with significant cardiac disease Hemodynamically unstable patients Patients with altered mental status Empiric antibiotics for unstable or immunocompromised patients External cooling mechanism rarely indicated