Succinylcholine pretreatment using gallamine or mivacurium during rapid sequence induction in children: a randomized, controlled study.

STUDY OBJECTIVE: To determine if pretreatment with either gallamine or mivacurium before succinylcholine in children is associated with reduction in fasciculations; postoperative myalgias; or serum levels of potassium, creatinine phosphokinase (CPK), and myoglobin. DESIGN: Prospective, randomized, double-blinded study. SETTING: Operating room at a children's hospital. PATIENTS: 45 ASA physical status IE children, aged 3 to 15 years, scheduled for emergency surgery. INTERVENTIONS: The children received either normal saline 0.5 mL, mivacurium chloride 0.03 mg. kg(-1), or gallamine triethiodide 0.04 mg. kg(-1)2 minutes prior to rapid sequence induction (RSI) using thiopental sodium 5 mg. kg(-1), fentanyl 2 microg. kg(-1), and succinylcholine 2 mg. kg(-1). MEASUREMENTS: Serum potassium concentration (0, 3, 5, 7.5, and 15 min), myoglobin concentration (5 and 15 min), and CPK concentration (0 min and 24 hr). Fasciculation and myalgia were rated on a 0 to 3 score. MAIN RESULTS: There was no difference between groups for fasciculation (p = 0.87) or myalgia score (p = 0.52). The mivacurium group had significantly less increase in potassium at 5 minutes (0.45 vs. 0.0, p = 0.01), myoglobin at 5 minutes (56 vs. 2, p < 0.001), myoglobin at 15 minutes (128 vs. 2.5, p < 0.001), and CPK at 24 hours (399 vs. 138, p < 0.001) following succinylcholine when compared with normal saline. Additionally, we found a significant level of association (p < 0.001) between fasciculation and myoglobin levels and fasciculation and CPK levels (p < 0.001). Gallamine was not effective in reducing the increase of potassium, myoglobin, or CPK. However, the dose of gallamine used for pretreatment was 13 times less than the dose of mivacurium. CONCLUSIONS: Administration of mivacurium 0.03 mg. kg(-1) intravenously 2 minutes before administration of succinylcholine 2 mg. kg(-1) in children is effective in reducing the increase in serum potassium at 5 minutes, the increase in myoglobin at 5 minutes and 15 minutes, and the increase in CPK at 24 hours.

The potency of succinylcholine in obese adolescents.

UNLABELLED: We constructed a single-dose response curve for succinylcholine in 30 obese adolescents during thiopental-fentanyl anesthesia administration by using 100 microg/kg, 150 microg/kg, or 250 microg/kg IV. The maximal response (percent depression of neuromuscular function) of the adductor pollicis to supramaximal train-of-four stimuli was recorded by using a Datex (Helsinki, Finland) relaxograph. Linear regression and inverse prediction were used to determine doses of succinylcholine to produce 50% (ED(50)), 90% (ED(90)), and 95% (ED(95)) depression of neuromuscular function. The ED(50), ED(90), and ED(95) were 152.8 microg/kg (95% confidence interval: 77.8-299.5), 275.4 microg/kg (95% confidence interval: 142-545.7), and 344.3 microg/kg (95% confidence interval: 175.3-675. 3), respectively. This ED(50) is similar to the dose reported for similarly aged, nonobese adolescents, 147 microg/kg. The previously reported ED(95) for succinylcholine in nonobese adolescents, 270 microg/kg, is within the 95% confidence interval generated for ED(95) in our study. IMPLICATIONS: The potency estimates for succinylcholine in obese (body mass index > 30 kg/m(2)) adolescents are comparable to those in similarly aged nonobese adolescents when dosing is calculated based on total body mass and not lean body mass. When a rapid sequence induction of anesthesia is considered in an obese adolescent, the dose of succinylcholine should be based on actual (not lean) body mass.

Juvenile laryngeal papillomatosis: scary anaesthetic!

We describe three children ages 20 to 33 months who presented for surgical resection of their laryngeal papillomata. Their anaesthetic management revealed the severity of obstruction which these children presented and the obstacles that faced the anaesthesiologist trying to secure the airway and provide adequate ventilation. The airway obstruction had both a fixed and a dynamic component to it. This was evidenced by the ability of the children to maintain ventilation when spontaneously breathing. But, they exhibited total obstruction when ventilation was attempted via mask using positive pressure. It is possible to encounter obstruction to ventilation after the trachea has been intubated because of papillomata that were 'shaved off,' filling the tracheal tube lumen.

A study of desmopressin and blood loss during spinal fusion for neuromuscular scoliosis: a randomized, controlled, double-blinded study.

BACKGROUND: Studies examining the use of desmopressin acetate (DDAVP) have shown variable results in DDAVP's efficacy for reducing blood loss. Studies of adults having cardiac surgery and of children having spinal fusion have suggested that patients with complicated medical histories and complex surgical procedures may benefit from use of DDAVP. Therefore, this study was designed to examine the homeostatic effects of DDAVP in children with severe cerebral palsy undergoing spinal fusion. METHODS: A randomized, double-blinded, and placebo-controlled trial of DDAVP was designed to enroll 40 patients. However, termination of the study was advised by the Institutional Review Board after 21 patients were enrolled. All patients had spastic quadriplegic-type cerebral palsy and were randomly assigned to one of two groups. The DDAVP group received 0.3 microg/kg DDAVP in 100 ml normal saline, and the placebo group received normal saline alone. All patients were anesthetized with nitrous oxide, oxygen, isoflurane, and fentanyl. Factor VIIIC and von Willebrand's factor (vWF) concentrations were measured in blood drawn before DDAVP infusion and 1 h after infusion. Blood pressure was maintained at a systolic pressure of less than 100 mmHg. Use of crystalloids, packed erythrocytes, platelets, and fresh frozen plasma were based on criteria established by protocol. Estimated blood loss was assessed by weighing sponges and measuring suctioned blood from canisters. RESULTS: Estimated blood loss (intraoperative and postoperative) and amount of packed erythrocytes transfused were similar for the DDAVP and placebo groups. Concentrations of both factor VIIIC and vWF were significantly greater after DDAVP infusion when compared with concentrations after placebo infusion. CONCLUSIONS: In the children who had complex spinal fusion, there was no difference in estimated blood loss between those who received DDAVP and those who received a placebo. Administration of DDAVP significantly increased factor VIIIC and vWF levels.

Can final EMG baseline be used as a reference to calculate neuromuscular recovery?

BACKGROUND: Investigations recording recovery times of muscle relaxants have used initial or final baseline of a neuromuscular trace, or both, as a reference for data analysis. We evaluated the use of final baseline of EMG traces as a reliable reference to calculate recovery times. METHODS: We analyzed EMG traces from 82 children who had full spontaneous neuromuscular recovery following a single dose of mivacurium. Times from administration of mivacurium to 25, 50, 75, and 90% EMG recoveries were measured using both initial and final baselines as a reference. EMG traces with final baseline of 100 +/- 10% of the initial baseline were regarded as optimal. Recovery times from all other traces were compared to the times obtained from these optimal traces. Poor final baseline was defined as that of < 80% of initial baseline. Inter-group comparisons were made using Kruskal-Wallis test followed by Mann-Whitney U tests. RESULTS: EMG recovery times were similar for optimal traces whether the reference was the initial or the final baseline of the EMG trace. If the final baseline was used as the reference, then traces with poor final EMG baseline also showed similar neuromuscular recovery times. If the initial baseline was used as the reference for EMG traces with poor final baseline, then neuromuscular recovery times became 24-55% longer (P < 0.05). CONCLUSIONS: We conclude that the final baseline of an EMG trace can be used as a reference for calculations of neuromuscular recovery times following a bolus injection of mivacurium.

Comparison of cuffed and uncuffed endotracheal tubes in young children during general anesthesia.

BACKGROUND: Uncuffed endotracheal tubes are routinely used in young children. This study tests a formula for selecting appropriately sized cuffed endotracheal tubes and compares the use of cuffed versus uncuffed endotracheal tubes for patients whose lungs are mechanically ventilated during anesthesia. METHODS: Full-term newborns and children (n = 488) through 8 yr of age who required general anesthesia and tracheal intubation were assigned randomly to receive either a cuffed tube sized by a new formula [size(mm internal diameter) = (age/4) + 3], or an uncuffed tube sized by the modified Cole's formula [size(mm internal diameter) = (age/4) + 4]. The number of intubations required to achieve an appropriately sized tube, the need to use more than 21.min-1 fresh gas flow, the concentration of nitrous oxide in the operating room, and the incidence of croup were compared. RESULTS: Cuffed tubes selected by our formula were appropriate for 99% of patients. Uncuffed tubes selected by Cole's formula were appropriate for 77% of patients (P < 0.001). The lungs of patients with cuffed tubes were adequately ventilated with 2 1.min-1 fresh gas flow, whereas 11% of those with uncuffed tubes needed greater fresh gas flow (P < 0.001). Ambient nitrous oxide concentration exceeded 25 parts per million in 37% of cases with uncuffed tubes and in 0% of cases with cuffed tubes (P < 0.001). Three patients in each group were treated for croup symptoms (1.2% cuffed; 1.3% uncuffed). CONCLUSIONS: Our formula for cuffed tube selection is appropriate for young children. Advantages of cuffed endotracheal tubes include avoidance of repeated laryngoscopy, use of low fresh gas flow, and reduction of the concentration of anesthetics detectable in the operating room. We conclude that cuffed endotracheal tubes may be used routinely during controlled ventilation in full-term newborns and children during anesthesia.

Recovery from doxacurium infusion administered to produce immobility for more than four days in pediatric patients in the intensive care unit.

Doxacurium was administered by titrated infusion to 14 pediatric patients for 4.7-12.3 days after laryngotracheal reconstruction to produce minimum spontaneous movement and less than five posttetanic movements of the first toe after stimulation of the posterior tibial nerve. Recovery was documented by stimulation of the ulnar nerve with 2 Hz for 2 s (train-of-four [TOF]) at intervals of 1 min and measurement of the ratio of the fourth to the first response (TOF ratio) at the adductor pollicis. During spontaneous recovery, the TOF ratio was between 0.4 and 0.7 for 0.6-3.3 h, mean (SEM) 2.2 (0.31) h. The TOF ratio equaled 1 between 4.7 and 23.0 h, mean (SEM) 11.0 (2.1) h after termination of doxacurium infusion. In six of the patients, weakness and decreased coordination were noted for a few days to weeks postoperatively. There were no complications related to impairment of upper airway function or ventilation in those patients who had recovery of neuromuscular transmission to the extent of TOF ratio equal to 1 prior to extubation or in those patients in whom weakness or lack of coordination was noted after tracheal extubation.

Combinations of high-dose vecuronium and mivacurium provide similar paralysis and intubation conditions to succinylcholine in paediatric patients.

This randomized blinded study tested the hypothesis that equipotent doses of vecuronium and mivacurium given in combination could achieve onset times to 90% neuromuscular block (B90) and intubation scores similar to succinylcholine. Thirty children were randomly assigned to one of three groups as follows. Group Sux received a single dose (1 mg.kg-1) of succinylcholine followed by normal saline. Group V1M1 received 0.08 mg.kg-1 of vecuronium followed by 0.1 mg.kg-1 of mivacurium. Group V2M2 received 0.16 mg.kg-1 of vecuronium followed by 0.2 mg.kg-1 of mivacurium. Anaesthesia consisted of propofol, fentanyl, and nitrous oxide. Neuromuscular response was monitored by adductor pollicis electromyography (Datex NMT). Sixty s after administration of the first injection, the laryngoscopy began, with the anaesthesiologist scoring the ease of intubation on a four category scale as excellent, good, poor, or inadequate. Time from injection to B90 was 39 (2.6)s after succinylcholine, which was not significantly different from 48 (3.5)s after vecuronium 0.16 mg.kg-1 and mivacurium 0.2 mg.kg-1 (V2M2). Mean time to B90 for group V1M1 was 64 (4.7)s, which was significantly different from that in group Sux. The intubation score was 'excellent' for all patients in groups Sux and V2M2 and for only seven of ten patients in group V1M1. Only combination of vecuronium (0.16 mg.kg-1) and mivacurium (0.2 mg.kg-1) provided rapid onset of neuromuscular blockade and excellent intubating conditions comparable to succinylcholine 1 mg.kg-1. This combination did result in prolonged recovery times.

Dose response of succinylcholine at the adductor pollicis of children with cerebral palsy during propofol and nitrous oxide anesthesia.

Children with cerebral palsy may be resistant to paralysis induced by nondepolarizing neuromuscular blocking drugs. Potency of a bolus of succinylcholine in children with cerebral palsy has not been studied previously. Therefore, we measured the response of the adductor pollicis to succinylcholine in children with cerebral palsy anesthetized with propofol and nitrous oxide. Forty children between the ages of 2 and 10.2 yr with spastic quadriplegic cerebral palsy were randomly assigned to receive 100, 175, 250, or 375 micrograms/kg of succinylcholine during anesthesia with propofol and nitrous oxide. The ulnar nerve was stimulated with a train-of-four supramaximal stimulus every 10 s and the compound electromyogram of the adductor pollicis recorded by a Datex NMT monitor. Plasma cholinesterase activity was measured in all patients with three different substrates (propionylthiocholine, benzoylcholine, and succinylcholine). Dibucaine number was also determined using inhibition of benzoylcholine degradation. ED50 of succinylcholine was 146.8 micrograms/kg with 95% confidence intervals of 111.4-193.7 micrograms/kg. ED95 of succinylcholine was 360.5 micrograms with 95% confidence intervals of 273.3-475.5 micrograms/kg. We conclude that children with cerebral palsy are slightly sensitive to succinylcholine, but probably not sufficiently to be clinically important.

Intrapleural streptokinase as adjunctive treatment for persistent empyema in pediatric patients.

Successful treatment of persistent empyema by intrapleural streptokinase is described in five pediatric patients. Their ages ranged from 18 months to 7 years. All experienced dramatic improvement in the resolution of their empyemas following intrapleural streptokinase. Improved chest tube drainage occurred concurrently with clinical improvement. Intrapleural instillation of streptokinase appears to be a safe adjunctive therapeutic tool to facilitate drainage of persistent empyema in the small number of pediatric patients in whom it has been employed. Additional study will be required to further assess the long-term therapeutic efficacy and consequences of intrapleural streptokinase therapy.

Efficacy of intranasal midazolam in facilitating suturing of lacerations in preschool children in the emergency department.

Sedating children safely and effectively for minor laceration repair is a well-recognized clinical problem. A randomized, double-blind, and controlled study was conducted to evaluate the efficacy of intranasal midazolam for reducing stress during the suturing of lacerations in preschool children. Fifty-nine children with simple lacerations that required suturing were randomly assigned to one of three groups. Group 1 received intranasal midazolam, 0.4 mg/kg, prior to suturing. Group 2 received an equivalent volume of normal saline intranasally prior to suturing as a placebo. Group 3 was the control group and received no intervention prior to suturing. Heart rate, respiratory rate, blood pressure, and pulse oximetry were monitored at 5-minute intervals throughout the procedure. Subjective variables were also measured at 5-minute intervals and included a cry score, a motion score, and a struggle score. Parent satisfaction was measured via a short telephone interview the following day. There were no significant differences in outcome between the placebo group and the control group. Their results were pooled and compared with the results for the midazolam group. The midazolam group showed significant reductions for mean heart rate, maximum heart rate, and maximum systolic blood pressure when compared with the placebo/control group. Scores for two of the three subjective variables, cry and struggle, were significantly reduced for the midazolam group. The papoose board was considered unnecessary in retrospect for more than half of patients in the midazolam group compared with only one fifth of patients in the placebo/control group.(ABSTRACT TRUNCATED AT 250 WORDS)