Succinylcholine, fasciculations and myoglobinaemia

Effects of rocuronium pretreatment on muscle enzyme levels following suxamethonium

BACKGROUND

The effects of different time intervals between rocuronium pretreatment and suxamethonium administration on muscle-derived enzymes and myoglobin were evaluated.

METHODS

Fifty-two patients, aged 3-6 years, were allocated randomly to receive pretreatment of either rocuronium 1 min or 4 min, or a placebo, before suxamethonium. Serum creatine-phosphokinase (CK), lactate dehydrogenase (LDH), alanine aminotransferase, aspartate aminotransferase (AST) and myoglobin concentrations were measured before treatment and at 30 min, 6 h and 24 h after suxamethonium administration.

RESULTS

Mean serum CK and myoglobin concentrations in the rocuronium groups were significantly less than in the saline group 24 h and 30 min after suxamethonium administration, respectively (P < 0.05). There were no significant differences between the rocuronium groups. Mean LDH and AST concentrations were higher at 6 h and 24 h after suxamethonium administration compared with preadministration levels, respectively (P < 0.05).

CONCLUSIONS

We concluded that intervals of 1 min or 4 min between the rocuronium and suxamethonium administrations have the same effect on enzyme levels.

Postmortem serum uric acid and creatinine levels in relation to the causes of death

Serum uric acid (UA) and creatinine (Cr) mainly derive from skeletal muscle tissues. Although, remarkable postmortem stability of the serum levels has been reported, there appears to be very poor knowledge of the diagnostic value in investigation of death, except for uremia. The aim of the present study was to evaluate postmortem serum UA and Cr levels using 395 forensic autopsy cases, in comparison with blood urea nitrogen (BUN), for investigation of the pathophysiology of death with special regard to the causes of death involving possible skeletal muscle damage, e.g. due to hypoxia, heat or agonal convulsions. Cr and BUN showed relatively good topographic stability in the cadaveric blood, whereas, UA was often much higher in the right heart blood than in the left heart and peripheral blood, independent of postmortem intervals. Moderate to marked elevation of Cr and BUN accompanied with hyperuricemia was observed in delayed death. In the acute death cases (survival time <30 min), UA, especially in the right heart blood, showed a considerable elevation in mechanical asphyxiation and drowning. The Cr level in fire victims with a lower carboxyhemoglobin (COHb) level (<60%) was significantly higher than in those with the possible fatal level (>60%). A similar elevation of Cr was observed in fatalities from heat stroke and methamphetamine (MA) poisoning. The observations suggested that hyperuricemia in acute death may be indicative of advanced hypoxia and that elevated Cr level may reflect the skeletal muscle damage, especially due to thermal influence.

Post-mortem urinary myoglobin levels with reference to the causes of death

To evaluate pathophysiological significance of post-mortem urinary myoglobin levels in determining the cause of death, we investigated 210 forensic autopsy cases, partially in comparison with serum levels. Post-mortem serum myoglobin levels were extraordinary high in most cases possibly due to post-mortem change. Urinary myoglobin levels did not correlate with the serum levels, showing possible post-mortem elevation in cases of a prolonged post-mortem period over 48h. A high (>1000 ng/ml), moderate (100-1000 ng/ml), slight (50-100 ng/ml) and not significant (<50 ng/ml) elevation of urinary myoglobin were observed in 26, 43, 31 and 110 cases, respectively. Half the highly elevated cases were those with a survival time over 24h. In cases of minor muscle injury such as head trauma, elevation of urinary myoglobin level was closely related to longer survival. In acute/subacute deaths with a post-mortem interval within 48h, a significant difference was observed in relation to the blood carboxyhemoglobin (COHb) levels of fire victims: myoglobinuria over 100 ng/ml was more frequently and markedly observed in cases with COHb below 60% than over 60%, suggesting muscle damage in fatal burns. Similar elevation was observed in heat stroke victims, and also in some cases of acute and subacute death from polytrauma, asphyxiation, drowning, electricity and spontaneous cerebral bleeding, but not in myocardial infarction. Thus, it was suggested that high post-mortem urinary myoglobin levels in acute and subacute death cases may be a possible indicator of antemortem massive skeletal muscle damage as well as exertional muscle hyperactivity or convulsive disorders associated with hypoxia.

Rapid sequence intubation of the pediatric patient. Fundamentals of practice

Rapid-sequence intubation and rapid sequence induction of general anesthesia are synonyms and refer to the technique of choice for tracheal intubation in many pediatric patients in the emergency department. The principles of safe practice and basic standards of care uniformly apply to all clinical situations in which the technique is performed. RSI has two basic technical components: induction of general anesthesia and direct laryngoscopy with tracheal intubation. The technique is a prescribed protocol that can be modified slightly by the clinical circumstances. RSI is designed to rapidly create ideal intubating conditions, attenuate pathophysiologic reflex responses to direct laryngoscopy and tracheal intubation, and reduce the risk for pulmonary aspiration. Optimal performance requires appropriate training and knowledge, technical skill, and sound medical judgment. Medical and airway evaluation, careful patient selection, recognition of the need for consultation or safer alternatives, thorough familiarity with appropriate drug management, and attention to detail are essential for minimizing the risk for adverse complications. RSI with a rapid injection of preselected dosages of an anesthetic induction agent and muscle relaxant is the pharmacologic technique of choice. Premedication should not be routinely used. Anticipation, recognition, and management of complications are inherent to the competent delivery of all medical care. The unanticipated difficult airway is arguably the most severe complication of RSI, and all individuals performing the technique must prepare in advance a specific plan for this scenario. As with all such skills or procedures, a quality assurance program is important to monitor care, and individuals practicing RSI need to take appropriate steps to maintain competence.

[Localized rhabdomyolysis after anaphylactic shock caused by suxamethonium]

A young woman without remarkable medical history, experienced a life threatening anaphylactoid reaction after induction of general anaesthesia for an emergency curettage. Hypersensitivity reaction involving IgE antibodies against suxamethonium was proven by positive skin test and detection of specific IgE by radio-immuno assay. After intensive therapy for 2 to 3 hours, the patient exhibited rhabdomyolysis localized on both calves. This complication, which required fasciotomies, did not result in renal failure. Local and general outcome was good. Rhabdomyolysis was due to compartmental ischaemia following shock and local external compression in the lithotomy position.

The effect of ketamine or thiamylal on succinylcholine-induced myoglobinemia under halothane anesthesia in adults

We studied the effect of intravenous (IV) thiamylal or ketamine on the increases in serum myoglobin, creatine kinase (CK), and potassium induced by succinylcholine under halothane anesthesia. Ninety patients were divided into three groups. In Group O, succinylcholine (1.0 mg/kg) was administered after an the inhaled induction of anesthesia with halothane. In Group T, thiamylal (4.0-5.0 mg/kg), and in Group K, ketamine (1.5-2.0 mg/kg) was injected prior to succinylcholine administration. Anesthesia was maintained with halothane, nitrous oxide, and oxygen. Myoglobin increased in Group O at 60 min to 855 ng/mL (median) and CK to 98.6 IU/L. These increases were significantly higher than those of Group T (110 ng/mL and 66.4 IU/L) and Group K (110 ng/mL and 57.0 IU/L). Potassium increased in Group O only. There was no significant difference between Groups T and K for any of the three values. These results indicate that IV thiamylal and ketamine both suppress the increases of myoglobin, CK, and potassium, and that in cases when succinylcholine is used, both drugs can help to avoid myoglobinemia and limit the increases of CK and potassium.

Neuromuscular disorder in intensive care unit patients treated with pancuronium bromide. Occurrence in a cluster group of seven patients and two sporadic cases, with electrophysiologic and histologic examination

During six consecutive months, seven patients admitted to our ICU (15 beds, general ICU, approximately 300 intubated patients per year) for acute respiratory failure requiring intubation and mechanical ventilation presented with a peculiar neuromuscular disorder. After the occurrence of this cluster group of patients, we detected two more similar but isolated cases in the following 18 months, ie, altogether 9 patients in 2 years of observation, or 1.55 percent of all intubated patients in our ICU. Sedation was achieved using midazolam, curarization was effected with the neuromuscular non-depolarizing agent pancuronium bromide (PB), and corticosteroids were administered to eight patients. Shortly after discontinuation of sedation and curarization, we observed a persistent tetraparetic syndrome and/or peroneal palsy with a concomitant increase of serum creatine kinase (CK). None of the patients was septic or had the multisystem organ failure. A strong association between CK increase and PB administration was found, whereas no patient suffered severe liver or kidney failure. The duration of the neurologic deficit ranged from 4 to 52 weeks, with only partial recovery for some patients; the duration of dysfunction was apparently related to the total dose of corticosteroids received. Two patients had difficulty being weaned from the respirator and required tracheostomy. Electrophysiologic studies showed signs of axonal neuropathy and myopathic changes, ie, motor units of brief duration, small amplitude, overly abundant for the voluntary effort being exerted. Muscle biopsies showed significant myopathic alterations, with foci of muscle necrosis in most patients and minimal lymphocytic inflammation in one patient. The neurologic complication described differs from the polyneuropathy in critically ill patients. Furthermore, PB or corticosteroids or both appear to be the causal agents. The duration of the neuromuscular dysfunction may be related to concomitant steroid therapy. The CK enzyme seems to be a marker of the disorder. This disorder is associated with myopathic alterations and axonal degeneration in some patients. Pancuronium bromide should be used with caution, particularly when associated with steroids therapy, and it may cause difficulty in weaning patients from the respirator.

The night after surgery. Postoperative management of the pediatric outpatient--surgical and anesthetic aspects

Outpatient or "ambulatory" anesthesia and surgery has revolutionized the way surgery is practiced in the United States. Safe, reliable, inexpensive, and convenient outpatient surgery is an attractive option for parents, children, health care providers, and insurers.

Midazolam pretreatment does not ameliorate myoglobinemia or the clinical side effects of succinylcholine

STUDY OBJECTIVE

To determine whether the levels of serum myoglobin and the occurrence of fasciculations and postoperative symptoms following a single dose of succinylcholine are modified by the prior administration of midazolam.

DESIGN

Randomized, double-blind, placebo-controlled study.

SETTING

Outpatient surgical service of a university hospital.

PATIENTS

69 ASA physical status I and II healthy, adult female outpatients undergoing laparoscopy (for diagnosis or tubal ligation) with general anesthesia that included succinylcholine.

INTERVENTIONS

Patients received pretreatment of either a saline placebo (Group 1, n = 31) or intravenous midazolam 0.03 mg/kg (Group 2, n = 38) 5 minutes before succinylcholine.

MEASUREMENTS AND MAIN RESULTS

Serum myoglobin prior to pretreatment and at 5 (t5) and 30 (t30) minutes after succinylcholine was determined by radioimmunoassay. Pain was assessed by telephone interview 24 to 36 hours postoperatively. Baseline myoglobin levels ranged from 14 to 69 ng/ml; the 5- and 30-minute samples varied widely (range, 16 to 900 ng/ml). The rise was 3 or more SDs above the baseline mean in 23% and 42% of Group 1 at t5 and t30, respectively, and in 21% and 35% of Group 2 at t5 and t30, respectively. The differences between groups were not significant. The frequency of fasciculations (77% in Group 1, 87% in Group 2), postoperative sore throat (64% in Group 1, 57% in Group 2), and myalgias (44% in Group 1, 51% in Group 2) also was not significantly different between groups.

CONCLUSIONS

Midazolam had no effect on myoglobin level or postoperative symptoms following succinylcholine.

Neuromuscular effects of succinylcholine following different pretreatments

STUDY OBJECTIVE

To study the neuromuscular effects (onset, intensity, and duration of block) of succinylcholine following different pretreatments.

DESIGN

Randomized open study.

SETTING

University-affiliated hospital.

PATIENTS

Fifty ASA physical status I and II adult inpatients undergoing elective ophthalmic surgery.

INTERVENTIONS

Succinylcholine 0.5 mg/kg was administered after no pretreatment or after pretreatment with d-tubocurarine 0.05 mg/kg intravenously (IV) 3 minutes before, chlorpromazine 0.1 mg/kg i.v. 3 minutes before, alpha-tocopherol (vitamin E) 600 mg in three divided doses orally at 6-hour intervals, or aspirin 600 mg orally 1 hour before in groups of ten patients each.

MEASUREMENTS AND MAIN RESULTS

Neuromuscular block by stimulation of the ulnar nerve at the wrist by application of train-of-four stimuli at 2 Hz every 12 seconds and recording the force of contraction of the adductor pollicis muscle. There was no significant difference in the time to occurrence of maximum block (49 to 53 seconds), reappearance of the twitch response (254 to 307 seconds), or complete recovery of twitch response (532 to 607 seconds) between the groups receiving no pretreatment and those pretreated with chlorpromazine, alpha-tocopherol, or aspirin. However, the time to maximum block (71 seconds) was significantly longer and the time to reappearance of the response (172 seconds) was significantly shorter (both p < 0.05) in the d-tubocurarine pretreated group in comparison with the control group. The time to complete recovery (420 seconds) also was shorter but not significantly different.

CONCLUSIONS

Of the pretreatments used, only d-tubocurarine interferes with the neuromuscular blocking effects of succinylcholine. Chlorpromazine, which attenuates the muscle pains as well as the increase in creatine kinase and can be administered with the same convenience, may be a better pretreatment in the prevention of side effects of succinylcholine.

Rapid-sequence intubation of head trauma patients: prevention of fasciculations with pancuronium versus minidose succinylcholine

INTRODUCTION

Fasciculations during rapid-sequence intubation may lead to increased intracranial pressure and emesis with aspiration. Standard rapid-sequence intubation requires a nondepolarizing blocking agent before succinylcholine administration.

HYPOTHESIS

Prevention of fasciculations during rapid-sequence intubation of head trauma patients can be accomplished as safely and effectively with minidose succinylcholine as with a defasciculating dose of pancuronium.

DESIGN

A prospective, randomized, double-blind study.

SETTING

An inner-city county trauma center with 70,000 patient visits per year.

PARTICIPANTS

Sequential adult head trauma patients requiring rapid-sequence intubation who had no contraindications to succinylcholine or pancuronium.

INTERVENTIONS

Each head trauma patient requiring rapid-sequence intubation who met the inclusion criteria received standard rapid-sequence intubation maneuvers and lidocaine (1 mg/kg) IV. Patients were randomized to receive either minidose succinylcholine (0.1 mg/kg) or pancuronium (0.03 mg/kg) IV one minute prior to the full paralytic dose of succinylcholine (1.5 mg/kg) IV. Fasciculations were recorded using a graded visual scale.

RESULTS

Of 46 patients, eight of 19 (42%) in the pancuronium group and six of 27 (22%) in the succinylcholine group experienced fasciculations. No statistically significant difference in fasciculations was detected between the two groups using chi 2 analysis. Complete relaxation of the cords was present in all but two patients, one in each group. No patient in either group experienced emesis or significant dysrhythmias.

CONCLUSION

Pretreatment with minidose succinylcholine causes no greater incidence of fasciculations than pancuronium in rapid-sequence intubation of head trauma patients in an ED setting. Thus succinylcholine may be used as the sole paralytic agent in rapid-sequence intubation of head trauma patients.

Serum creatine kinase levels after succinylcholine in children with "muscle, eye and brain disease"

Four boys belonging to a group of children affected by a rare form of muscular dystrophy with eye and brain involvement, termed the "muscle, eye and brain disease" (MEB), were anaesthetized for various eye examinations and surgery. On some occasions succinylcholine was used during anaesthesia and the initially elevated serum creatine kinase (CK) values increased from a range of 122 to 1200 units.L-1 to a range of 4350 to 9690 units.L-1 22 hours after anaesthesia. CK values after anaesthesia without succinylcholine remained at the initially elevated levels. Rectal temperatures of the children were normal. These findings suggest that succinylcholine should be avoided in patients with MEB disease.