Succinylcholine-induced cardiac arrest in unsuspected Duchenne muscular dystrophy

A case history is presented of a three-year-old boy with unsuspected Duchenne muscular dystrophy, who suffered a cardiac arrest following the administration of a single dose of succinylcholine during a halothane anaesthetic. The arrest was associated with lack of fasciculations, muscle rigidity, hyperkalemia, myoglobinuria, and massive elevation of serum creatine phosphokinase. Asystole was prolonged and refractory to treatment, although cardiac activity was eventually restored. The possible cause of the circulatory collapse is discussed and reports of similar cases reviewed. Neither succinylcholine nor halothane should be employed in cases with known or suspected Duchenne muscular dystrophy.     

Hyperkalemic cardiac arrest following succinylcholine administration: The use of extracorporeal membrane oxygenation in an emergency situation

We report an 11-year-old male with undiagnosed myopathy, who developed cardiac arrest secondary to severe rhabdomyolysis and hyperkalemia following succinylcholine administration. The patient required extracorporeal membrane oxygenation support from which he was eventually weaned successfully. He died eleven days after the cardiac arrest as a result of apparent ischemic brain injury.     

Cardiac arrest during anesthesia induction with halothane and succinylcholine in an infant. Massive hyperkalemia and rhabdomyolysis in suspected myopathy and/or malignant hyperthermia

This report describes a cardiac arrest that occurred in a 4-month-old infant during induction of anesthesia. During the administration of N2O/O2 and halothane via a face mask tachycardia was noted and rigor followed the application of succinylcholine for intubation. Shortly thereafter cardiac arrest occurred; 15 min later we found a profound metabolic acidosis as well as signs of rhabdomyolysis with a serum potassium level of 10.3 mmol/l and an increase in serum creatine kinase (CK). While performing cardiopulmonary resuscitation (CPR) and treating the acid-base imbalance and hyperkalemia, we administered--suspecting malignant hyperthermia (MH)--dantrolene. Approximately 60 min post-arrest we achieved stabilization of the vital signs. During the following hours the CK level rose to 99, 600 IU/l and myoglobinuria of 360,000 micrograms/l confirmed the extent of the rhabdomyolysis. The infant was discharged home without detectable sequelae after 2 1/2 weeks. Comparisons with corresponding case reports in the literature lead to the supposition that our patient suffered from a myopathy thus far undiagnosed. To what extent a MH episode may have contributed to the clinical picture cannot be determined at present. The spectrum of adverse reactions to volatile anesthetics and succinylcholine in patients with myopathic disorders is presented and discussed. As in other case reports, the dramatic course described here also demonstrates that in addition to CPR and treatment of the acid-base and electrolyte imbalances, administration of dantrolene should be considered at an early stage.     

Differing effect of agonist and antagonist muscle relaxants on cat jaw muscles

Mouth closure and an increased resistance to mouth opening follow succinylcholine administration in humans. To elucidate the effects of succinylcholine on masticatory muscle function, mouth opening in the cat, produced by a constant test force, was measured during steady state halothane anesthesia. After baseline measurements, either succinylcholine (0.3 mg.kg-1 of body weight) or vecuronium (0.1 mg.kg-1 of body weight) was infused intravenously, and mouth opening measurements were repeated for up to 30 min. Concomitantly, muscle relaxant effect was quantified by measurement of the neurally-evoked tibialis anterior muscle response. All animals given succinylcholine displayed active jaw closure, which was followed by an increased resistance to mouth opening. This increased resistance was present after cessation of fasciculations and during complete twitch suppression. It lasted beyond the time at which the limb muscle twitch had fully recovered. Vecuronium administration was associated with a decreased resistance to mouth opening without a closing action. The initial jaw closure and the subsequently increased resistance to mouth opening after succinylcholine administration during halothane anesthesia in the cat are comparable with mouth opening changes after succinylcholine administration during inhalation anesthesia in humans. The cat may serve as an animal model for study of the mechanisms involved in responses of jaw muscles to succinylcholine with use of techniques inappropriate in humans.     

Cardiac effects of self-taming of succinylcholine and repeated succinylcholine administration

Pretreatment with small (10 mg) doses of succinylcholine (“self-taming”) decreases the incidence of muscle fasciculations following succinylcholine administration and may decrease the incidence of other unwanted effects. This study was designed to assess the cardiac effects of such self-taming and to assess the degree of protection afforded against bradydysrhythmias following subsequent succinylcholine administration. Sixty patients were studied and allocated randomly to three groups of twenty. Each group was assigned a different form of pretreatment. Patients in group I received 10 mg of succinylcholine immediately after induction. Patients, in group II were treated with d-tubocurarine 0.04 mg ? kg^-1 three minutes before induction. Patients in group III received no pretreatment. All patients were induced with thiopentone 4 mg ? kg^-1 followed by succinylcholine 1 mg ? kg^-1 45 seconds later. A second dose of succinylcholine 1 mg ? kg^-1 was administered to the patients in the two pretreatment groups between four and five minutes after the first dose of succinylcholine. Following both the first and second doses of succinylcholine patients in the self-taming group showed a significantly greater incidence of bradydysrhythmias when compared to the other two groups. It is concluded that the use of a self-taming technique is potentially hazardous, and that it does not confer protection against repeated succinylcholine administration.     

Succinylcholine apnoea: attempted reversal with anticholinesterases

Anticholinesterases were administered in an attempt to antagonize prolonged neuromuscular blockade following the administration of succinylcholine in a patient later found to be homozygous for atypical plasma cholinesterase. Edrophonium 10 mg, given 74 min after succinylcholine, when train-of-four stimulation was characteristic of phase II block, produced partial antagonism which was not sustained. Repeated doses of edrophonium to 70 mg and neostigmine to 2.5 mg did not antagonize or augment the block. Spontaneous respiration recommenced 200 min after succinylcholine administration. It is concluded that anticholinesterases are only partially effective in restoring neuromuscular function in succinylcholine apnoea despite muscle twitch activity typical of phase II block.     

Precurarization with rocuronium prevents fasciculations and biochemical changes after succinylcholine administration

OBJECTIVE: To determine the efficacy of rocuronium to prevent fasciculations and biochemical changes after succinylcholine administration. PATIENTS AND METHODS: Prospective, randomized double-blind trial enrolling 60 ASA I-II patients scheduled for elective surgery under general anesthesia. The patients were assigned to 2 groups to receive either 0.06 mg x Kg(-1) of rocuronium or physiological saline solution 90 seconds before administration of 1.5 mg x Kg(-1) of succinylcholine. The incidence and severity of fasciculations and serum concentrations of potassium before anesthesia and 3, 5, and 20 minutes after succinylcholine administration were recorded. Other serum concentrations recorded were myoglobin, creatinine phosphokinase and lactate before anesthesia and 20 minutes after succinylcholine administration. RESULTS: The increases in potassium levels at 3 and 5 minutes (0.3 +/- 0.3 and 0.2 +/- 0.4 mmol x L(-1)) and in myoglobin levels at 20 minutes (38.9 +/- 31.7 ng x mL(-1)) were attenuated by precurarization with rocuronium. The incidence of fasciculations was significantly lower (p<0.001) and their severity significantly less (p<0.001) in patients who received rocuronium before administration of succinylcholine. CONCLUSIONS: Precurarization with rocuronium 90 seconds before succinylcholine administration reduces the incidence and severity of fasciculations and prevents increases in serum potassium and myoglobin concentrations.     

Serum potassium following succinylcholine in patients with brain tumours

Serum potassium levels were measured in 15 patients with brain tumours between 3–7 cm diameter, during thiopentone/70 per cent N₂O in O₂ anaesthesia, with mask ventilation controlled to maintain a constant end-tidal CO₂ concentration. Potassium levels were determined one minute before and one and ten minutes after administration of succinylcholine 1.0mg·kg^?1 IV. No statistically significant increase in serum potassium occurred following succinylcholine, nor were there any ECG changes associated with succinylcholine administration. Use of succinylcholine in patients with brain tumours does not appear to cause elevation of serum potassium levels or ECG changes.     

Quantitation of the interaction between atracurium and succinylcholine using closed-loop feedback control of infusion of atracurium

The authors used closed-loop feedback control of infusion of atracurium to study the effect of prior administration of succinylcholine on neuromuscular blockade induced by atracurium in patients undergoing otolaryngologic surgery. Anesthesia was maintained with nitrous oxide in oxygen, flunitrazepam, and fentanyl. Of 14 patients given atracurium, seven were given prior administration of succinylcholine and seven were not. Interaction between the two drugs was quantified by determining the asymptotic steady-state rate of infusion necessary to produce a constant 90% neuromuscular blockade. This was accomplished by applying nonlinear curve-fitting to data on the cumulative dose requirement during anesthesia. The neuromuscular blocking effect of atracurium was found to be greater after prior administration of succinylcholine. The asymptotic steady-state rate of infusion (+/- SD) for atracurium was 0.27 +/- 0.06 mg.kg-1.h-1 for patients given succinylcholine and 0.38 +/- 0.10 mg.kg-1.h-1 for those not given succinylcholine. The clinical implication of this study is that the clinician should be aware of the fact that an induction dose of 1 mg/kg of succinylcholine does reduce atracurium requirement for 90% neuromuscular blockade by approximately 30%.     

Cardiac arrhythmia after succinylcholine administration in a patient with Guillain-Barré syndrome--a case report

We report a case of cardiac arrhythmia occurring in a Guillain-Barré syndrome (GBS) patient after succinylcholine administration during third endotracheal intubation, on day 13 of illness. The probable cause of arrhythmia is succinylcholine-induced hyperkalemia. Of interest, this case demonstrated in the same patient that arrhythmia only occurred during third intubation, when duration of illness is prolonged, and not during previous two intubation episodes, despite succinylcholine was also being used. In GBS, muscle denervation resulted in up-regulation of acetylcholine receptors at neuromuscular junctions, causing the muscle cell membrane to become supersensitive to succinylcholine, leading to severe hyperkalemia and arrhythmia when succinylcholine was administered.     

Rocuronium combined with i.v. lidocaine for rapid tracheal intubation

BACKGROUND: Rocuronium (ORG 9426) has been shown to have an onset of action more rapid than other nondepolarizing neuromuscular blocking agents and to provide intubating conditions similar to those of succinylcholine 60-90 s after administration. We compared the intubating conditions and hemodynamic changes after the administration of rocuronium 0.6 mg kg(-1) and lidocaine 1.5 mg kg(-1) with rocuronium alone and succinylcholine 60 and 90 s after administration. METHODS: One hundred and twenty-five adult patients of ASA physical status I or II scheduled for elective surgery were randomly divided into five groups. After propofol administration in all patients, patients in group Su (succinylcholine), group R60 (rocuronium) and group RL60 (rocuronium-lidocaine) were intubated within 60 s, while groups RL90 and R90 were intubated 90 s after the administration of rocuronium and succinylcholine. Laryngoscopy was performed and intubating conditions were graded by an experienced anesthetist blind to the muscle relaxant allocation. RESULTS: In this study, groups Su, RL60, R90 and RL90 had similar intubation scores, which were significantly better than that for group R60. Heart rate did not increase after intubation in groups Su, RL60 and RL90. CONCLUSION: The combination of lidocaine (1.5 mg kg(-1)) and low-dose rocuronium (0.6 mg kg(-1)) along with propofol is clinically equivalent to succinylcholine, improves intubating conditions in 60 s and effectively blocks increases in heart rate after intubation.     

Plasma cholinesterase deficiency in a neonate

We report a two-day-old infant who had a period of apnoea lasting six hours following the intravenous administration of succinylcholine (Sch). The results of her plasma cholinesterase level and dibucaine number indicate a congenital absence of plasma cholinesterase (PChE) enzyme, although both parents and siblings had normal cholinesterase levels and dibucaine numbers. This is believed to be the youngest reported case of prolonged apnoea after the administration of succinylcholine.     

Should the routine use of atropine before succinylcholine in children be reconsidered?

It is common practice to administer atropine before a first dose of succinylcholine in infants and children. However, the administration of succinylcholine without atropine has not been investigated in children. This study was designed to compare cardiovascular changes after the administration of either atropine with succinylcholine or succinylcholine alone. In 41 ASA I or II patients aged from 1 to 12 yr anaesthesia was induced with thiopentone 5 mg · kg^?1. Patients were randomly allocated to receive either atropine 20μg · kg^?1 and succinylcholine 1.5 mg · kg^?1 (n = 20) or succinylcholine 1.5 mg · kg^?1 alone (n = 21). Heart rate and rhythm were recorded continuously from two minutes before induction until two minutes after tracheal intubation. Blood pressure was measured non-invasively before and after induction of anaesthesia and both immediately and two minutes after laryngoscopy. One self-limiting episode of bradycardia was recorded during laryngoscopy in a child who received atropine. Heart rate increased in both groups compared with baseline values (108 ± 25), with a greater increase in patients who had received atropine (150 ± 13) than in those who had not (128 ± 18) (P < 0.05). There was no difference in mean arterial pressure or incidence of arrythmias between the two groups. No recorded arrythmias were judged to be clinically important by a cardiologist. The incidence of bradycardia after succinylcholine in the absence of atropine in children aged from 1 to 12 yr appears to be lower than previously estimated. The use of atropine before a single dose of succinylcholine in children deserves to be reconsidered.     

The effects of succinylcholine on heart rate and rhythm in infants]

The authors examined the possible variations of cardiac activity in 91 infants aged between a few days and six months in order to study the changes following administration of succinylcholine during general anaesthesia. No variations in rhythm and/or heart rate occurred, not even in those children to whom atropine had not been injected intravenously before succinylcholine.     

Methylparaben and propylparaben do not alter cerebral blood flow in humans

In vitro studies suggest that the preservatives methylparaben and propylparaben included in some multidose vials of succinylcholine are the cerebral vasodilators responsible for the increases in intracranial pressure (ICP) documented after succinylcholine administration. To test this hypothesis, we measured cerebral blood flow (CBF) and cerebral blood flow velocity (CBFV) with inhaled 133Xenon and transcranial Doppler respectively in healthy humans before and after the intravenous administration of methylparaben and propylparaben. We found no change in either CBF or CBFV after the paraben injections and therefore conclude that it is unlikely that the rise in ICP seen with succinylcholine is caused by cerebral arterial vasodilatation from the preservatives methylparaben and propylparaben.     

Nifedipine attenuates the intraocular pressure response to intubation following succinylcholine

Forty patients without eye disease, undergoing elective nonophthalmic surgery, were studied to evaluate the efficacy of sublingual nifedipine in attenuating the intraocular pressure response to succinylcholine administration, laryngoscopy and intubation. The patients were randomly given either nifedipine 10 mg or placebo sublingually 20 minutes before induction of anaesthesia. Intraocular pressure (IOP) and systolic blood pressure (SBP) were recorded before and after induction of anaesthesia. The IOP response to succinylcholine administration, laryngoscopy and intubation was significantly less in patients receiving nifedipine (P > 0.01). The mean maximum rise in IOP above basal level at one minute postintubation was 7.82 mmHg in the control group compared with 0.15 mmHg in the nifedipine pretreated group. These results suggest that sublingual nifedipine is effective in attenuating the IOP response after succinylcholine administration, laryngoscopy and intubation.     

Serum potassium after enflurane-succinylcholine induction of anesthesia in children receiving rectal midazolam as premedication.

The administration of succinylcholine causes an increase in serum potassium (K+) concentrations in healthy patients. The purpose of this study was to investigate serum K+ changes following intravenous succinylcholine in children and to evaluate the effect of rectal midazolam pretreatment on these changes. Forty healthy children between the ages of 2 and 7 yr, and who were to undergo oral surgical procedures under general anesthesia were randomly assigned to receive either placebo (saline) or 0.25, 0.35, or 0.45 mg/kg midazolam administered rectally as premedication 30 min before induction of inhalational anesthesia. Blood was drawn after induction with enflurane and at 1, 2, 3, 4, and 5 min after administration of 1 mg/kg succinylcholine to determine changes in serum K+. Although the results indicate a significant increase in serum K+ after succinylcholine in all groups, midazolam pretreatment failed to cause any observable attenuation in the hyperkalemic response.     

Comparison of the Intubation Conditions Provided by Rapacuronium (ORG 9487) or Succinylcholine in Humans during Anesthesia with Fentanyl and Propofol

Background: Currently, the only approved muscle relaxant with a rapid onset and short duration of action is succinylcholine, a drug with some undesirable effects. Rapacuronium is an investigational nondepolarizing relaxant that also has a rapid onset and short duration and consequently should be compared with succinylcholine in its ability to facilitate rapid tracheal intubation.

Methods: This prospective, randomized clinical trial involved 336 patients. Anesthesia was induced with fentanyl and propofol and either 1.5 mg/kg rapacuronium or 1.0 mg/kg succinylcholine. The goal was to accomplish tracheal intubation by 60 s after administration of the neuromuscular blocking drug. Endotracheal intubation was performed, and conditions were graded by a blinded investigator. Recovery of neuromuscular function was assessed by electromyography.

Results: Intubation conditions were evaluated in 236 patients. Intubation by 60 s after drug administration occurred in 100% of patients with rapacuronium and in 98% with succinylcholine. Intubation conditions were excellent or good in 87% of patients with rapacuronium and in 95% with succinylcholine (P < 0.05). The time (median and range) to the first recovery of the train-of-four response was 8.0 (2.8-20.0) min with rapacuronium and 5.7 (1.8-17.7) min with succinylcholine (P < 0.05). The overall incidence of adverse effects was similar with both drugs.     

Muscular injury after succinylcholine and electroconvulsive therapy

Both succinylcholine and seizures cause muscular injury during electroconvulsive therapy. We compared the muscular damage in two groups of patients. The psychiatric patient group received succinylcholine for electroconvulsive therapy. The surgical patient group received succinylcholine for endotracheal intubation. Serum myoglobin was measured as a marker for muscular injury and myalgic symptoms were also recorded. Serum myoglobin increased from baseline in both groups at 5 and 20 min. The surgical patients, however, had a higher myoglobin level than the psychiatric patients at 5 and 20 min after the administration of succinylcholine (P < 0.001). The median (range) of myoglobin concentration at 20 min in psychiatric patients was 32.6 (23.1-60.1) ng/mL, compared with 61.2 (31.6-1687.0) ng/mL in surgical patients. The incidence of myalgia was not different between the two groups. In conclusion, we unexpectedly conclude that the psychiatric patients who received electroconvulsive therapy had less effect of muscular damage associated with succinylcholine than the surgical patients did. IMPLICATIONS: Both succinylcholine and electroconvulsive therapy cause muscular injury. However, we unexpectedly found that psychiatric patients who received succinylcholine and electroconvulsive therapy had less muscular damage than surgical patients who received succinylcholine for intubation. Therefore, appropriate use of succinylcholine can attenuate the muscular damaging effect from the therapy.     

Comparison of the intubation conditions provided by rapacuronium (ORG 9487) or succinylcholine in humans during anesthesia with fentanyl and propofol.

BACKGROUND: Currently, the only approved muscle relaxant with a rapid onset and short duration of action is succinylcholine, a drug with some undesirable effects. Rapacuronium is an investigational nondepolarizing relaxant that also has a rapid onset and short duration and consequently should be compared with succinylcholine in its ability to facilitate rapid tracheal intubation. METHODS: This prospective, randomized clinical trial involved 336 patients. Anesthesia was induced with fentanyl and propofol and either 1.5 mg/kg rapacuronium or 1.0 mg/kg succinylcholine. The goal was to accomplish tracheal intubation by 60 s after administration of the neuromuscular blocking drug. Endotracheal intubation was performed, and conditions were graded by a blinded investigator. Recovery of neuromuscular function was assessed by electromyography. RESULTS: Intubation conditions were evaluated in 236 patients. Intubation by 60 s after drug administration occurred in 100% of patients with rapacuronium and in 98% with succinylcholine. Intubation conditions were excellent or good in 87% of patients with rapacuronium and in 95% with succinylcholine (P < 0.05). The time (median and range) to the first recovery of the train-of-four response was 8.0 (2.8-20.0) min with rapacuronium and 5.7 (1.8-17.7) min with succinylcholine (P < 0.05). The overall incidence of adverse effects was similar with both drugs. CONCLUSIONS: A 1.5-mg/kg dose of rapacuronium effectively facilitates rapid tracheal intubation. It can be considered a valid alternative to 1.0 mg/kg succinylcholine for this purpose.