Thiopental Sodium
Indications
Thiopental Sodium is used for:
Status epilepticus, Induction of anesthesia, Reduction of raised intracranial pressure
Adult Dose
Intravenous
Induction of anaesthesia
Adult: 100-150 mg of a 2.5 or 5% solution injected over 10-15 sec repeated every 30-60 sec according to response or as a continuous infusion of a 0.2 or 0.4% solution. Max: 500mg. Max in pregnancy: 250mg.
Status epilepticus
Adult: In conjunction with assisted ventilation: 75-125 mg as a 2.5% solution.
Reduction of raised intracranial pressure
Adult: Intermittent bolus inj of 1.5-3.5 mg/kg, if adequate ventilation is provided.
Elderly: Dose reduction may be needed.
Hepatic impairment: Dose reduction may be needed.
Child Dose
Intravenous
Induction of anaesthesia
Child: 2-7 mg/kg over 10-15 seconds; repeated after 1 minute if needed..
Status epilepticus
Child: 5 mg/kg by slow IV inj followed by, neonates: continuous iv infusion of 2.5 mg/kg/hr;
>1 month: 2-8 mg/kg/hr. Adjust infusion dose according to response.
Reduction of raised intracranial pressure
Child: 3 mth-15 yr: initial 5-10-mg/kg IV followed by a continuous IV infusion at 1-4 mg/kg/hr.
Renal Dose
Renal impairment: Dose reduction may be needed.
Administration
Contra Indications
Thiopental Sodium for Injection is contraindicated in patients with severe respiratory embarrassment, hypersensitivity to barbiturates, status asthmaticus, variegate or acute intermittent porphyria, and inflammatory conditions of the mouth, jaw, and neck and in the absence of suitable veins for intravenous administration. Thiopental Sodium for Injection is also relatively contraindicated in severe cardiovascular disease, hypotension or shock, and conditions in which the hypnotic effect may be prolonged or potentiated, i.e. excessive premedication, Addison's disease, hepatic or renal dysfunction, myxedema, increased blood urea, severe anemia and myasthenia gravis.
Precautions
Hypovolaemia; history of severe asthma, severe cardiac disease, severe anaemia, hyperkalaemia, toxaemia, myasthenia gravis, myxoedema; severe renal or hepatic disease; muscular dystrophies, adrenocortical insufficiency; increased intracranial pressure; elderly, pregnancy, lactation. Avoid extravasation or intra-arterial administration. IV inj of concentrated thiopental solution e.g. 5% may cause thrombophloebitis.
Pregnancy-Lactation
Interactions
Possible increase in difficulty in producing anaesthesia in patients taking alcohol or CNS depressants. Additive action with other CNS depressants including sedatives, hypnotics, nitrous oxide or alcohol. Increased hypotension and excitatory effects with phenothiazine antipsychotics. Increased hypnotic effect with antipsychotic. Decreased requirement of thiopental sodium with metoclopramide, sulfisoxazole, aspirin, meprobamate, probenecid and other highly protein bound drugs.
Potentially Fatal: Increased resp depression with opioids.
Adverse Effects
Side effects of Thiopental Sodium :
Coughing, hiccupping, sneezing, muscle twitching, laryngospasm, bronchospasm. IV: tissue necrosis (if extravasation occurs). Intra-arterial: Severe arterial spasm with burning pain, blanching of forearm and hands and gangrene of digits.
Potentially Fatal: Respiratory depression, arrhythmias, circulatory failure and anaphylactoid reactions.
Mechanism of Action
Thiopental sodium, a short-acting barbiturate anaesthetic, is a CNS depressant inducing hypnosis and anaesthesia but not analgesia. It has also been used in the control of refractory tonic-clonic status epilepticus and to reduce increased intracranial pressure in neurosurgical patients.