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alfentanil (al-fen-ta-nil)

Alfenta, imageRapifen


Therapeutic: analgesic adjuncts, opioid analgesics

Pharmacologic: opioid agonists

Schedule II


Analgesic adjunct used to maintain anesthesia with barbiturate/nitrous oxide/oxygen. Analgesic (continuous IV infusion) with nitrous oxide/oxygen while maintaining general anesthesia. Primary induction anesthetic when endotracheal intubation and mechanical ventilation are required.


Binds to opiate receptors in the CNS, altering the response to and perception of pain while causing generalized CNS depression. Therapeutic Effects: Relief of moderate to severe pain. Anesthesia.

Adverse Reactions/Side Effects

CNS: dizziness, sleepiness. EENT: blurred vision. Resp: apnea, respiratory depression. CV: bradycardia, hypotension, tachycardia, arrhythmias, hypertension. GI: nausea, vomiting. MS: thoracic muscle rigidity, skeletal muscle rigidity.


Examination and Evaluation

  • Assess respiration, and notify physician immediately if patient exhibits any interruption in respiratory rate (apnea) or signs of respiratory depression, including decreased respiratory rate, confusion, bluish color of the skin and mucous membranes (cyanosis), and difficult, labored breathing (dyspnea). Monitor pulse oximetry and perform pulmonary function tests (See Appendix I) to quantify suspected changes in ventilation and respiratory function. Apnea or excessive respiratory depression requires emergency care.

  • Be alert for excessive sedation, and notify physician or nurse immediately if patient is unconscious or extremely difficult to arouse.

  • Use appropriate pain scales (visual analog scales, others) to document whether this drug is successful in helping manage the patient's pain.

  • Assess blood pressure (BP) and compare to normal values (See Appendix F). Report changes in BP, either a problematic decrease in BP (hypotension), or a sustained increase in BP (hypertension).

  • Assess heart rate, ECG, and heart sounds, especially during exercise (See Appendices G, H). Report any rhythm disturbances or symptoms of arrhythmias, including palpitations, chest discomfort, shortness of breath, fainting, and fatigue/weakness.

  • Assess dizziness that might affect gait, balance, and other functional activities (See Appendix C). Report balance problems and functional limitations to the physician and nursing staff, and caution the patient and family/caregivers to guard against falls and trauma.

  • Be alert for residual muscle rigidity and decreased thoracic and limb movements after rapid IV administration. Report a sustained increase in muscle tone.


  • Implement appropriate manual therapy techniques, physical agents, and therapeutic exercises to reduce pain and help wean patient off opioid analgesics as soon as possible.

  • Because of the risk of respiratory depression, arrhythmias, and abnormal BP responses, use caution during aerobic exercise and other forms of therapeutic exercise. Assess exercise tolerance frequently (BP, heart rate, respiratory rate, fatigue levels), and terminate exercise immediately if any untoward responses occur (See Appendix L).

  • Help patient explore other nonpharmacologic methods to reduce chronic pain (relaxation techniques, exercise, counseling, and ...

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