CASE REPORT fentanyl, infusion

Continuous Intravenous Infusion Fentanyl for Sedation and Analgesia of the Multiple Trauma Patient

Fentanyl is an attractive agent for analgesia in the emergency department. Its use in this setting has been limited to IV bolus administration. We report successful sedation, muscle relaxation, and analgesia of a multiple trauma patient with fentanyl IV bolus and continuous infusion in the ED. [Walsh M, Smith GA, Yount RA, Ferlic FJ, Wieschhaus MF: Continuous intravenous infusion fentanyl for sedation and analgesia of the multiple trauma patient. Ann Emerg Med August 1991;20:913-915.]

I N T R O D U C T I O N Fentanyl is a synthetic narcotic analgesic that has a potency 150 times

that of morphine.l Because of its rapid onset, duration of 30 to 40 minutes, and lack of significant complications at the lower dose, fentanyl has be- come an ideal choice for rapid, short-term analgesia in the emergency de- partment. Recently, an extensive review of fentanyl use in the ED reported the safety and efficacy of this form of analgesia in this setting) There were few complications, and most occurred in the alcohol-intoxicated patient.

A lively correspondence ensued. ,~ With this controversy in mind, we re- port a case of prolonged sedation, analgesia, and muscular relaxation in a multiple trauma patient caused by a continuous fentanyl infusion.

CASE REPORT A 50-kg, 21-year-old woman sustained bilateral midshaft femoral frac-

tures in a motor vehicle accident. After a brief period of stabilization in the ED, the patient was taken to the radiology department for computed to- mography (CT) scan of the head and abdomen. During the studies, she became combative and screamed loudly while thrashing about. Her vital signs and arterial blood gases were normal. A serum alcohol and subse- quent drug screen were negative. The patient vomited, and 25 mg IV pro- methazine followed by 10 mg IV valium stopped the vomiting but failed to calm her. Meperidine 50 mg IV was then given without any sedation. At this point, 100 I~g fentanyl IV was infused in 50-t~g aliquots over two to three minutes with some sedation. Ten minutes later, an additional 100 t~g was given in a similar fashion to complete the CT.

Approximately 30 minutes after the final dose of fentanyl, the patient again became combative. During the next two hours in the ED, she was given an additional 300 t~g fentanyl in 50-1~g boluses. She was intubated to protect the airway but soon was awake, moving her extremities, pulling out her IV lines, and requiring restraints. After intubation and hyperven- tilation, it was hoped that she could be sedated with IV morphine. How- ever, there was no response to a 14-rag IV bolus of morphine.

Despite negative head CT, we believed that the patient probably had a cerebral contusion of the temporal lobe. (In fact, 48 hours later, a CT head scan demonstrated both frontal and temporal lobe contusions.) We wanted to stabilize the patient before surgery and contemplated paralyzing her. We could not guarantee predictable and adequate sedation for this patient be- cause of her manifest tolerance to meperidine, morphine, and diazepam. Neuromuscular blockade without controlled and reliable sedation would subject her to unnecessary physiologic and psychologic stress, which we wanted to avoid because of our suspicion, later confirmed, that she had a cerebral contusion. Because fentanyl is 150 times more potent than mor-

Mark Walsh, MD, FACEP* Greg A Smith, MDt Robert A Yount, MD, PhD¢ Frederick J Ferlic, MDt Martin F Wieschhaus, MD§ South Bend, Indiana

From the Departments of Emergency Medicine,* Anesthesiology, t Surgery,$ and Family Practice,§ Saint Joseph's Medical Center, South Bend, Indiana.

Received for publication October 22, 1990. Revision received January 25, 1991. Accepted for publication February 18, 1991.

Address for reprints: Mark Walsh, MD, FACER Department of Emergency Medicine, Saint Joseph's Medical Center, 801 East LaSalle Street, South Bend, Indiana 46617.

132/913 Annals of Emergency Medicine 20:8 August 1991

FENTANYL Walsh et a{

phine, l we knew that the 14-rag bo- lus of morphine corresponded to only a fraction of the total dose of fen- tanyl that had been required to se- date her. Rather than search for a new effective bolus dose of morphine to sedate the patient and then use a cont inuous morphine infusion to maintain sedation, we decided to use the medication that had proven effec- tive in the preceding hours and fol- low with a continuous fentanyl infu- sion.

Therefore, after consultation with an anesthesiologist, we elected to use a continuous fentanyl infusion for se- dation, muscle relaxation, and anal- gesia. The patient was given a 100-b~g fentanyl bolus followed by a contin- uous fentanyl infusion. This infusion was prepared by diluting 50 mL (50 p.g/mL} of fentanyl in 500 mL of 5% dextrose in water to give a concentra- tion of 5 ~,g/mL. Sedation and light anesthesia that allowed for eye open- ing when her name was called were achieved at a rate of 5.0 ~tg/min (0.1 p.g/kg/min). The patient was trans- ferred to the ICU, and over the next eight hours the fentanyl infusion was gradually discontinued. The patient's fractures were subsequently repaired. She made an uneventful recovery.

DISCUSSION Fentanyl is always given as a bolus

for analgesia in the ED. Outpatient use of constant infusion fentanyl has been described for elective gyne- cologic surgery, such as dilatation and extraction procedures in the op- erating room setting. 4 However, pro- longed fentanyl infusion in the ED for analgesia, sedation, or muscle re- laxation has not been described.

We elected to use fentanyl in lieu of a neuromuscular blocking agent combined with a narcotic because of our desire to avoid the hypotension associated with morphine, the pa- tient's relative tolerance to diazepam, and our prior success in sedating her with fentanyl. We found an easily titratable, immediately reversible, and safe agent that gives excellent se- dation, analgesia, and muscle relax- ation in the ED. In si tuat ions in which there is manifest tolerance to benzodiazepenes or neuromuscular blocking agents are contraindicated, fentanyl represents an alternative to the combinat ion of neuromuscular blocking agents and diazepam or morphine, which is most often used

20:8 August 1991

to control these types of patients. Its use in this setting also allows for im- media te reversal and subsequent neurologic evaluation by a neuro- surgeon.

As with all narcotic analgesics, complications can follow the use of fentanyl. Although respiratory de- pression and vomiting are uncom- mon with a low dose, our patient was intubated to protect her airway given her cerebral contusions and un- stable condition. Even without these indications, intubation is necessary for a patient treated with a fentanyl infusion. Thoracic wall rigidity and glottic closure have been reported during the induction of anesthesia with high doses of fentanyl. -~ These complicat ions are easily reversed wi th naloxone. At the low-bolus doses, muscular rigidity and glottic closure are unlikely), 6 However, de- layed rigidity occurs in anesthetic doses four to six hours after surgery due to re-entry of fentanyl from ad- ipose tissue, muscle, and the gastro- intestinal tract.6, 7

Therefore, prolonged low-dose ad- min i s t r a t ion could theore t ica l ly cause fentanyl's accumulation with delayed respiratory depression. Other adverse drug reactions such as hyper- tension, bradycardia, s and gener- alized seizures have been reported with high doses of fentanyl, although the association between seizures and fentanyl is not conclusive. 2

We were able to maintain sedation, analgesia, and muscle relaxation at a starting dose of 5 btg/min (0.1 ~g/kg/ rain} after the initial bolus of fen- tanyl. This dose is at the low end of the spectrum for outpatient anesthe- sia in the operating suite, where an- esthesia was repor tedly obtained with a fentanyl infusion of 2 to 50 p.g/min following a 100-btg fentanyl bolus5

Although the early prior doses of meperidine, diazepam, and, subse- quently, morphine may have added to the sedative and analgesic effects of fentanyl, the total dose of fentanyl was much greater in potency com- pared with the doses of meperidine and morphine. Simply put, fentanyl provided the bulk of the sedation. Also, during most of the fentanyl in- fusion, the effects of the other medi- cations had probably dissipated.

We could have e lec ted to use higher doses of morphine until seda- tion, following with continuous mor-

Annals of Emergency Medicine

phine infusion. However, morphine, because of a low lipid solubility, has a ten- to 15-minute lag-to-peak effect. Fentanyl is more lipid soluble and therefore acts within one to two min- utes when given IV. 9 The choice of fentanyl bolus and infusion over morphine bolus and infusion was based no t o n l y on t h i s pha r - macokinetic difference but also on our desire to avoid hypotens ion , which occurs rarely with fentanyl but frequently with even small doses of morphine, s,m and on our earlier success in sedating our patient with frequent boluses of the more rapid- acting fentanyl.

Our decision to use a fentanyl in- fusion instead of a neuromuscular blocking agent combined with a nar- cotic or a benzodiazepene was based on our concern for the well-docu- mented and detrimental physiologic stress of neuromuscular blockade in the absence of guaranteed sedation. Recently, in traumatic brain injury, cont inuous morphine infusion re- duced the main baseline EEG activ- ity and decreased patient stimulation more than bolus morphine during en- dotracheal suction of intubated pa- tients. ~ For the reasons mentioned above, we elected to use fentanyl in- stead of morphine.

S U M M A R Y Fentanyl is an attractive agent for

analgesia, muscle relaxation, and se- dation in the ED. There is ample doc- umentation in the literature confirm- ing its safety and efficacy in this set- ting. We found that a fentanyl bolus followed by an infusion gave rapid, predictable, titratable, and reversible muscle relaxation, analgesia, and se- dation of a combative patient who had marked tolerance to other nar- cot ic analgesics and benzodiaze- penes. Such a use of fentanyl may provide an alternative to the com- bined use of neuromuscular blocking agents and narcotics or benzodiaz- epenes for patients with significant tolerance to benzodiazepenes or for patients in whom neuromuscular agents are contraindicated.

The authors thank Pat Sobchak for her preparation of the manuscript and Elaine Flemming, BSN, for her assistance in the care of this patient.

R E F E R E N C E S 1. Billmire DA, Neale HW, Gregory RO: Use of IV fen tanyl in the outpatient treatment of pediatric facial trauma. / "Fraum~l 1985;25:[079-1080.

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FENTANYL Walsh et al

2. Chudnofsky CR, Wright SW, Dronen SW, et al: The safety of fentanyl use in the emergency department. Am7 Emcrg Med 1989;L8:635,2639.

3 Dronen SC, Wright SW, Chudnofsky CR: Anes thctics in the ED iletter). Ann EmerR Med 1991]; 19:839-840.

4 White PF: Use of continuous infusion versus inter mittent bolus administration of fentanyl or ketamine during outpat ient anesthesia. Anesthesi¢dr~Ry 198~; 59:294 300.

5. Arandia HY, Patil VU: Glottic closure folh~wiil~

large dose of fentanyl (letter[. Anesthesi(dcJ~y 1987;66: 574 575

6. Caspi J, Klausner IM, Safadi T, ct al: Delayed respira- tory depression fl~llowing fentallyl anesthesia h}r car diac surgery. Crit Care Med 1988;16:238 240.

7. Klausner IM, Caspi ], Lelcuk S, et al: I)clayed mus cular rigidity and respiratory depression following fcn- tanyl anesthesia. Arch Surx 1988;123:66-67

8 Bailey PL, Stanley TH: l'harmacology of intravenous narcotic anesthetics, in Miller RD led): Ane.~lhv.~ia. cd

New York, Chtlrchill Livingstone, 1986, wll I, p

754-759

9. C~ok LD: Opioids, in l)ripps RD, Eckenhotf JE, Van ~ dam LI) Ceds}: Intrlldu~ii~Jll to Anesthesia. cd 7 Phila de]phia, WB Satmders, 1988, p 162

10 R~Jscow CE, Moss J, Philbin I)M, et al: Histamine release during morphine and fentany/ anesthesia , 4nv ; th;~ioh)~y 1982;56:93

11. Walsh 1C, Hoyt DB, Shackford SR, et al: A compari- son ot N}lus vemus COiltinuotts opiate administration i l l head injury: Effects of the processed EEG and intra crania/ pressure [ahstractl "haum~ 1990;30:930

134/915 Annals of Emergency Medicine 20:8 August 1991