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Rapacuronium bromide
pharmacology facts Rapacuronium Bromide LAWRENCE STUMP,
CRNA, MEd
Rapacuronium bromide (Raplon; Organon Inc, West Orange, NJ) is a new, fast-onset, short-duration surgical muscle relaxant. While anesthesia providers are learning how to use this new relaxant, PACU nurses must become aware of the potential problems associated with rapacuronium. This article compares and contrasts the effects of succinylcholine and rapacuronium. © 2000 by American Society of PeriAnesthesia Nurses.
I
N DECEMBER 1999, a new muscle relaxant, rapacuronium bromide (Raplon; Organon Inc, West Orange, NJ), was introduced to clinical practice. This new drug is exciting because it has significantly fewer side effects than succinylcholine with the advantage of succinylcholine’s fast onset and short duration. Since its introduction, there have been anecdotal reports by PACU nurses that some patients who received rapacuronium are arriving in PACU weak and in need of additional neuromuscular reversal. My aim in this article is to introduce rapacuronium by comparing and contrasting it with succinylcholine. Succinylcholine, introduced in 1951, has been the mainstay for rapid intubation of the trachea because of its rapid onset and short duration. However, the number and significance of undesirable side effects associated with succinylcholine (Table 1) prompted neuromuscular pharmacologists to search for an alternative muscle relaxant. This search has brought several useful drugs to
market but, until now, none that closely match the onset and duration of succinylcholine. Rapacuronium is a low-potency, fast-onset, short-duration steroidal muscle relaxant. The number and significance of rapacuronium’s side effects compared with succinylcholine are minimal and few. The side effects are (1) moderate vagolytic action in the clinical dose range, with resulting heart rate increases of 25% to 30% and a lowered blood pressure of 10% to 15% as a result of calcium channel blockade and (2) bronchospasm, which has been noted in the clinical trials and usually requires no treatment.2 Good intubating conditions are obtained in 60 seconds with both succinylcholine and rapacuronium at the indicated doses. Increasing the dose of rapacuronium does not shorten the onset time but does increase the duration of the block. Rapacuronium is also easily reversible by neostigmine. The significant difference between the drugs (Table 2) is their duration of action. This difference could be critical in those patients in whom intubation has failed. The clear advantage of succinyl-
Lawrence Stump, CRNA, MEd, is an Assistant Chief Nurse Anesthetist at the University of Michigan Medical Center, Ann Arbor, MI, and an Adjunct Instructor in Health Care, School of Health Professions and Studies, University of Michigan, Flint, MI. Address correspondence to Lawrence Stump, CRNA, MEd, 305 Lake Village Dr, #101, Ann Arbor, MI 48103-6543. © 2000 by American Society of PeriAnesthesia Nurses. 1089-9472/00/1504-0007$3.00/0 doi:10.1053/jpan.2000.9470
Table 1. Side Effects of Succinylcholine1
258
Hyperkalemia Fasciculations Atypical plasma ChE Malignant hyperthermia
Increased IOP Myalgias Phase II block
Increased ICP Myoglobinemia Bradycardia
Increased IGP Masseter spasm Severe hyperkalemia
Anaphylaxis
Abbreviations: IOP, intraocular pressure; ICP, intracranial pressure; IGP, intragastric pressure; ChE, cholinesterase.
Journal of PeriAnesthesia Nursing, Vol 15, No 4 (August), 2000: pp 258-259
RAPACURONIUM BROMIDE
259
Table 2. Onset and Duration3 Drug
Succinylcholine Rapacuronium
Dose
Onset
Duration
1.0 mg/kg 1.5 mg/kg
60-90 sec 60-90 sec
5-10 min 12-17 min
choline over rapacuronium is the latter’s short duration, which permits the recovery of the patient’s own respiratory efforts so that they may awaken and intubation can be accomplished by fiber-optic techniques. It remains to be seen what the niche for rapacuronium will be, but for now, anesthesia providers will be using this relaxant for intubation of the trachea and possibly for patients in whom only 1 or 2 additional doses of muscle relaxant are necessary. Dosing after the initial dose can cause significant extension of its duration and may require reversal. The use of rapacuronium followed by other relaxants has not been adequately studied and should be done cautiously.
Because rapacuronium is a short-duration muscle relaxant, recovery from neuromuscular blockade should occur by 17 minutes with 1 dose and about 30 minutes after a second dose. While anesthesia providers are learning how to use rapacuronium, it is important that they use nerve stimulators to assess recovery from block and to always reverse a dose of relaxant when there is any doubt. Given rapacuronium’s profile, patients may be weak in PACU because the dose was too large and/or the patient received inadequate or no reversal.
REFERENCES 1. Bevan DR: 1997 Review Course Lectures. Cleveland, OH, International Anesthesia Research Society, 1997, pp 9 2. Savarese JJ: 1998 Review Course Lectures. Cleveland, OH, International Anesthesia Research Society, 1998, pp 22 3. Wright PMC: A pharmacodynamic explanation for the rapid onset/offset of rapacuronium bromide. Anesthesiology 90:16, 1999
CRNA, MEd
Rapacuronium bromide (Raplon; Organon Inc, West Orange, NJ) is a new, fast-onset, short-duration surgical muscle relaxant. While anesthesia providers are learning how to use this new relaxant, PACU nurses must become aware of the potential problems associated with rapacuronium. This article compares and contrasts the effects of succinylcholine and rapacuronium. © 2000 by American Society of PeriAnesthesia Nurses.
I
N DECEMBER 1999, a new muscle relaxant, rapacuronium bromide (Raplon; Organon Inc, West Orange, NJ), was introduced to clinical practice. This new drug is exciting because it has significantly fewer side effects than succinylcholine with the advantage of succinylcholine’s fast onset and short duration. Since its introduction, there have been anecdotal reports by PACU nurses that some patients who received rapacuronium are arriving in PACU weak and in need of additional neuromuscular reversal. My aim in this article is to introduce rapacuronium by comparing and contrasting it with succinylcholine. Succinylcholine, introduced in 1951, has been the mainstay for rapid intubation of the trachea because of its rapid onset and short duration. However, the number and significance of undesirable side effects associated with succinylcholine (Table 1) prompted neuromuscular pharmacologists to search for an alternative muscle relaxant. This search has brought several useful drugs to
market but, until now, none that closely match the onset and duration of succinylcholine. Rapacuronium is a low-potency, fast-onset, short-duration steroidal muscle relaxant. The number and significance of rapacuronium’s side effects compared with succinylcholine are minimal and few. The side effects are (1) moderate vagolytic action in the clinical dose range, with resulting heart rate increases of 25% to 30% and a lowered blood pressure of 10% to 15% as a result of calcium channel blockade and (2) bronchospasm, which has been noted in the clinical trials and usually requires no treatment.2 Good intubating conditions are obtained in 60 seconds with both succinylcholine and rapacuronium at the indicated doses. Increasing the dose of rapacuronium does not shorten the onset time but does increase the duration of the block. Rapacuronium is also easily reversible by neostigmine. The significant difference between the drugs (Table 2) is their duration of action. This difference could be critical in those patients in whom intubation has failed. The clear advantage of succinyl-
Lawrence Stump, CRNA, MEd, is an Assistant Chief Nurse Anesthetist at the University of Michigan Medical Center, Ann Arbor, MI, and an Adjunct Instructor in Health Care, School of Health Professions and Studies, University of Michigan, Flint, MI. Address correspondence to Lawrence Stump, CRNA, MEd, 305 Lake Village Dr, #101, Ann Arbor, MI 48103-6543. © 2000 by American Society of PeriAnesthesia Nurses. 1089-9472/00/1504-0007$3.00/0 doi:10.1053/jpan.2000.9470
Table 1. Side Effects of Succinylcholine1
258
Hyperkalemia Fasciculations Atypical plasma ChE Malignant hyperthermia
Increased IOP Myalgias Phase II block
Increased ICP Myoglobinemia Bradycardia
Increased IGP Masseter spasm Severe hyperkalemia
Anaphylaxis
Abbreviations: IOP, intraocular pressure; ICP, intracranial pressure; IGP, intragastric pressure; ChE, cholinesterase.
Journal of PeriAnesthesia Nursing, Vol 15, No 4 (August), 2000: pp 258-259
RAPACURONIUM BROMIDE
259
Table 2. Onset and Duration3 Drug
Succinylcholine Rapacuronium
Dose
Onset
Duration
1.0 mg/kg 1.5 mg/kg
60-90 sec 60-90 sec
5-10 min 12-17 min
choline over rapacuronium is the latter’s short duration, which permits the recovery of the patient’s own respiratory efforts so that they may awaken and intubation can be accomplished by fiber-optic techniques. It remains to be seen what the niche for rapacuronium will be, but for now, anesthesia providers will be using this relaxant for intubation of the trachea and possibly for patients in whom only 1 or 2 additional doses of muscle relaxant are necessary. Dosing after the initial dose can cause significant extension of its duration and may require reversal. The use of rapacuronium followed by other relaxants has not been adequately studied and should be done cautiously.
Because rapacuronium is a short-duration muscle relaxant, recovery from neuromuscular blockade should occur by 17 minutes with 1 dose and about 30 minutes after a second dose. While anesthesia providers are learning how to use rapacuronium, it is important that they use nerve stimulators to assess recovery from block and to always reverse a dose of relaxant when there is any doubt. Given rapacuronium’s profile, patients may be weak in PACU because the dose was too large and/or the patient received inadequate or no reversal.
REFERENCES 1. Bevan DR: 1997 Review Course Lectures. Cleveland, OH, International Anesthesia Research Society, 1997, pp 9 2. Savarese JJ: 1998 Review Course Lectures. Cleveland, OH, International Anesthesia Research Society, 1998, pp 22 3. Wright PMC: A pharmacodynamic explanation for the rapid onset/offset of rapacuronium bromide. Anesthesiology 90:16, 1999