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METHOHEXITAL SODIUM

Medical Diagnosis and Drugs, Medications
METHOHEXITAL SODIUM
(meth-oh-hex'i-tal)
Brevital Sodium
Classifications: general anesthetic; barbiturate;
Therapeutic: general anesthetic; barbituate
Prototype: Thiopental
Pregnancy Category: B
Controlled Substance: Schedule IV

Availability

500 mg, 2.5 g, 5 g powder for injection

Action

Rapid, ultra-short-acting barbiturate anesthetic agent. More potent than thiopental but has less cumulative effect and shorter duration of action, and recovery is more rapid.

Therapeutic Effect

Induces brief general anesthesia without analgesia by depression of the CNS.

Uses

Induction of anesthesia, as supplement for other anesthetics, and as general anesthetic for brief operative procedures.

Contraindications

Hypersensitivity to methohexital sodium; agranulocytosis; barbiturate hypersensitivity; hepatic encephalopathy; intraarterial administration; shock, heart failure, PVD, severe hypo- and hypertension, respiratory depression, infants <1 mo; neonates.

Cautious Use

Pregnancy (category B), labor; adrenal insufficiency, anemia, carbamazepine hypersensitivity; cardiac disease, COPD; uncontrolled asthma, status asthmaticus, sleep apnea, respiratory insufficiency, CNS depression; depression, ethanol intoxication; exfoliative dermatitis; hepatic disease; hydantoin hypersensitivity, older adult; neuromuscular disease; obesity; porphyria; pulmonary disease, renal disease, uremia, renal impairment; seizure disorders, status epilepticus, seizures; shock.

Route & Dosage

Induction of Anesthesia
Adult: IV 50–120 mg at a rate of 5 mg q5min, then 20–40 mg q4–7min prn
Child/Infant: IM 6.6–10 mg/kg of 5% solution IV 1–2 mg/kg PR 20–35 mg/kg (max: 500 mg/dose)

Administration

Intravenous
  • Give to recumbent patient. Fall in BP may occur in susceptible patients receiving drug in upright position.
  • Note: Verify with physician correct IV or IM concentration for infants or children as well as rate of IV infusion for administration to children.

PREPARE: Direct: Prepare a 1% solution (10 mg/mL) by diluting with sterile water for injection, D5W, or NS. Use only clear, colorless solutions. Do not allow contact with rubber stoppers or parts of syringes treated with silicone because solution is incompatible with acid solutions (see IMCOMPATIBILITIES).  

ADMINISTER: Direct: Give 5 mg over 5–10 sec.  

INCOMPATIBILITIES Solution/additive: Atropine, chlorpromazine, glycopyrrolate, hydralazine, kanamycin, lidocaine, mechlorethamine, methyldopa, prochlorperazine, promazine, promethazine, streptomycin. Y-site: Fenoldopam.

  • Store drug in sterile water for injection at room temperature for at least 6 wk. Solutions prepared with isotonic NaCl injection or 5% dextrose injection are stable for ONLY about 24 h.

Adverse Effects (≥1%)

CV: Hypotension, cardiac arrhythmias, cardiac arrest. Musculoskeletal: Muscle spasm. CNS: Postoperative psychomotor impairment that persists for 24 hours, anxiety, drowsiness, emergence delirium, restlessness, and seizures. Respiratory: Bronchospasm, cough, hiccups, respiratory depression, apnea, dyspnea, respiratory arrest. Skin: Phlebitis and nerve injury adjacent to the injection site, local irritation, edema, ulceration, necrosis.

Interactions

Drug: Alcohol and other cns depressants enhance CNS depression.

Pharmacokinetics

Absorption: 17% absorbed PR. Distribution: Crosses CNS, placenta and excreted in breast milk. Metabolism: Oxidized in liver. Elimination: Primarily excreted in urine.

Nursing Implications

Assessment & Drug Effects

  • Hiccups are common, particularly with rapid injection; they sometimes persist after anesthesia.
  • Keep facilities for assisting respiration and administration of oxygen readily available in the event of respiratory distress.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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