methohexital

methohexital

Brevital

Brietal

Indications

Action

Pharmacokinetics

Time/action profile (anesthesia)

Contraindications/Precautions

Adverse Reactions/Side Effects

Central nervous system

• seizures (life-threatening)
• anxiety
• emergence delirium
• headache
• restlessness

Ear, Eye, Nose, Throat

• rhinitis

Respiratory

• apnea (life-threatening)
• laryngospasm (life-threatening)
• bronchospasm
• coughing
• dyspnea
• respiratory depression

Cardiovascular

• cardiorespiratory arrest (life-threatening)
• hypotension

Gastrointestinal

• abdominal pain
• hiccups
• nausea
• salivation
• vomiting

Dermatologic

• erythema
• pruritus
• urticaria

Local

• pain at IM site
• phlebitis at IV site

Musculoskeletal

• muscle twitching

Miscellaneous

• shivering (most frequent)
• allergic reactions

Interactions

Drug-Drug interaction

Route/Dosage

Availability (generic available)

Nursing implications

Nursing assessment

• Assess BP, ECG, heart rate, and respiratory status continuously throughout methohexital therapy. Methohexital should be used only by individuals qualified to administer anesthesia and experienced in endotracheal intubation. Equipment for this procedure should be immediately available. Apnea may occur immediately after IV injection, especially in the presence of opioid premedication.
• Monitor IV site carefully. Extravasation may cause pain, swelling, ulceration, and necrosis. Intra-arterial injection may cause arteritis, vasospasm, edema, thrombosis, and gangrene of the extremity.
Overdose may occur from rapid injection (drop in BP, possibly to shock levels) or excessive or repeated injections (respiratory distress, laryngospasm, apnea).

Potential Nursing Diagnoses

Implementation

• Do not confuse Brevital (methohexital) with Brevibloc (esmolol).
  • Dose is individualized according to depth of anesthesia desired; concurrent use of other medications and/or nitrous oxide; patient’s condition, age, weight, and sex.
  • Geriatric: Geriatric patients may require smaller doses than young patients. Tolerance may develop with repeated use, such as for burns. Individuals tolerant to alcohol or barbiturates may require higher doses.

• Intravenous Administration

• Intravenous: Repeated doses or continuous infusion of methohexital may cause prolonged somnolence and respiratory and circulatory depression. If the patient requires a second anesthetic in the same day, reduction in the dose of methohexital may be required.
  • Methohexital may be given in doses sufficient to produce deep surgical anesthesia, but such doses may cause dangerous respiratory and circulatory depression.
  • Premedication with anticholinergics (atropine, glycopyrrolate) may be used to decrease mucous secretions. Opioid analgesics may be administered preoperatively to enhance the poor analgesic effects of methohexital. Preoperative medications should be given so that peak effect is attained shortly before induction of anesthesia. Muscle relaxants, if required, should be administered separately.
• Diluent: Do not use diluents containing bacteriostats. Dilute 500 mg vial with 50 mL of sterile water for injection (preferred), D5W, or 0.9% NaCl. Concentration: 10 mg/mL (1% solution). Solution should be freshly prepared and used within 24 hr of reconstitution. Refrigerate and keep sealed. Do not administer solution containing a precipitate.
• Rate: Induction dose is administered at a rate not to exceed 1 mL (10 mg) over 5 sec.
• Continuous Infusion: Diluent: To prepare a 1% (10 mg/mL) solution, reconstitute each 2.5-g vial with 15 mL or each 5-g vial with 30 mL of sterile water for injection (preferred), D5W, or 0.9% NaCl. Initial solution will be yellow. Further dilute the 2.5-g vial in 250 mL or the 5-g vial in 500 mL. Concentration: 10 mg/mL (1% solution). Solution should be used only if clear and colorless.
  • Diluent: To prepare a 0.2% solution, dilute 500 mg in 250 mL of D5W or 0.9% NaCl. To avoid hypotonicity, do not dilute with sterile water. Concentration: 0.2% solution.
  • Solution is stable for 24 hr.
• Rate: Anesthesia is maintained by intermittent injections every 4–7 min or by continuous infusion.
• Syringe Compatibility: propofol.
• Syringe Incompatibility: glycopyrrolate
• Y-Site Compatibility: acyclovir, aminocaproic acid, atenolol, bivalirudin, bleomycin, carboplatin, cisplatin, cyclophosphomide, cytarabine, dactinomycin, dexmedetomidine, doxacurium, etoposide, fludarabine, fluorouracil, hydromorphone, ifosfamide, methotrexate, milrinone, mitoxantrone, nesiritide, octreotide, paclitaxel, pancuronium, pantoprazole, tigecycline, tirofiban, vasopressin, vincristine, voriconazole
• Y-Site Incompatibility: doxorubicin, epirubicin, eptifibitide, etoposide phosphate, fenoldopam, gemtuzumab, idarubicin, irinotecan, mechlorethamine, ondanestron, oxytocin, rocuronium, vecuronium, vinorelbine

Patient/Family Teaching

• Methohexital may cause psychomotor impairment for 24 hr after administration. Caution patient to avoid driving or other activities requiring alertness for 24 hr.
• Advise patient to avoid use of alcohol or other CNS depressants for 24 hr after anesthesia, unless directed by health care professional.

Evaluation/Desired Outcomes

• Loss of consciousness.
• Maintenance of desired level of anesthesia without complications.