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We studied the neuromuscular and cardiovascular effects of a single, rapidly administered intravenous dose of cisatracurium 0.15 mg.kg(-1) in 27 infants (aged 1-23 months) and 24 children (aged 2-12.5 years). After midazolam premedication, anaesthesia was induced and maintained with thiopental and alfentanil in addition to nitrous oxide in oxygen. Neuromuscular function was monitored by evoked adductor pollicis electromyography. At least 15 min after intubation, each patient received cisatracurium 0.15 mg.kg(-1) over 5 s. Complete neuromuscular blockade was produced by this dose in all but one infant. The mean (SD) onset time of maximal blockade was more rapid in infants [2.0 (0.8) min] than in children [3.0 (1.2) min], p = 0. 0011. The clinical duration of action of cisatracurium (recovery of evoked response to 25% of control) was significantly longer in infants [43.3 (6.2) min] than in children [36.0 (5.4) min], p < 0.0001. Once neuromuscular function started to recover, the rate of recovery was similar in both age groups. Changes in blood pressure and heart rate after the administration of cisatracurium were negligible in both age groups. Cisatracurium, at a dose of 0.15 mg. kg(-1), was effective and well tolerated in infants and children. [ABSTRACT FROM AUTHOR]

We studied the neuromuscular and cardiovascular effects of a single, rapidly administered intravenous dose of cisatracurium 0.15 mg.kg-1 in 27 infants (aged 1–23 months) and 24 children (aged 2–12.5 years). After midazolam premedication, anaesthesia was induced and maintained with thiopental and alfentanil in addition to nitrous oxide in oxygen. Neuromuscular function was monitored by evoked adductor pollicis electromyography. At least 15 min after intubation, each patient received cisatracurium 0.15 mg.kg-1 over 5 s. Complete neuromuscular blockade was produced by this dose in all but one infant. The mean (SD) onset time of maximal blockade was more rapid in infants [2.0 (0.8) min] than in children [3.0 (1.2) min], p = 0.0011. The clinical duration of action of cisatracurium (recovery of evoked response to 25% of control) was significantly longer in infants [43.3 (6.2) min] than in children [36.0 (5.4) min], p < 0.0001. Once neuromuscular function started to recover, the rate of recovery was similar in both age groups. Changes in blood pressure and heart rate after the administration of cisatracurium were negligible in both age groups. Cisatracurium, at a dose of 0.15 mg.kg-1, was effective and well tolerated in infants and children. [ABSTRACT FROM AUTHOR]

Objective: The role of laparoscopic surgery in pediatric inguinal hernia repair is unclear. We aimed to compare day-case laparoscopic hernia repair with open repair., Methods: A prospective, single-blinded randomized study in children aged 4 months to 16 years with unilateral inguinal hernia was performed. The primary outcome measure was the time to normal daily activities after surgery. Secondary outcome measures included postoperative pain, time in the operation room, results, and complications., Results: Eighty-nine patients were enrolled (laparoscopic hernia repair: 47, open repair: 42). The mean number of days to normal activity after laparoscopic hernia repair and open repair was 2.4 and 2.5, respectively. Thirty-seven (79%) patients with laparoscopic hernia repair and 20 (42%) with open repair required rescue analgesia postoperatively. The median pain score in the second postoperative morning was significantly higher after laparoscopic hernia repair. The median times in the operation room for laparoscopic hernia repair and open repair were 63 and 38 minutes, respectively. Surgical and cosmetic results were similar at up to 2 years' follow-up., Conclusions: Recovery and outcome were similar after open repair and laparoscopic hernia repair in children. Laparoscopic hernia repair was associated with increased theater time and postoperative pain.

Background: The aims of the present study were to determine the tracheal intubating conditions, onset time, duration of action, and hemodynamic responses following the administration of cisatracurium 0.15 mg x kg(-1) to infants and children., Methods: One hundred and eighty-one infants and children aged 1 month to 12 years were randomized to two groups to receive anesthesia with nitrous oxide-oxygen-halothane (group H) or nitrous oxide-oxygen-thiopental-fentanyl (group TF). Intubation conditions were assessed 120 s after cisatracurium administration using a 4-part scale. Neuromuscular transmission was monitored by recording the evoked compound electromyogram of the adductor pollicis., Results: The proportion of patients with excellent or good intubating conditions was similar in both groups (88 of 90, 98% in group H; 85 of 90, 94% in group TF). However, there was a significantly greater proportion of excellent intubating conditions in group H (79 of 90, 88%) compared with group TF (65 of 90, 72%) (P = 0.01) and recovery time was significantly longer in group H compared with group TF (P < 0.001). There was also a higher proportion of excellent intubating conditions in infants compared with older subjects (P = 0.02) and a shorter onset time (P < 0.001) and longer recovery time (P < 0.001) in younger compared with older patients. Changes in heart rate and arterial pressure were negligible 1 min following the cisatracurium administration., Conclusions: Cisatracurium 0.15 mg x kg(-1) produces acceptable intubating conditions at 120 s in the great majority of infants and children. Anesthesia background and age have significant effects on intubating conditions and duration of action of cisatracurium.

Background: The air leak test is recommended for assessing the appropriate size of an uncuffed tracheal tube (TT) in children. Our objectives were to determine whether there is a certain threshold air leak value beyond which a higher risk for adverse events after removal of TT can be predicted and to define other risk factors related to extubation., Methods: We enrolled 234 cases ranging from newborn to 9 years of age requiring tracheal intubation for elective or emergency surgery. General anesthesia was induced by a mask or intravenously. The TT size was calculated using the formula: [age (years)/4] + 4.5. After the induction of anesthesia, the patient's trachea was intubated and the correct position was confirmed. The attending anesthetist assessed the leak pressure. Incidences of adverse events (prolonged or barking cough, obstructed or prolonged inspiration or expiration, subcostal and sternal retractions, arterial desaturation, or laryngospasm) were recorded after removal of TT., Results: Ten patients were excluded from the study. A total of 218 children underwent 224 operations under general anesthesia. Children who had an absent air leak at 25 cmH(2)O pressure had 2.8 times more adverse events during emergence from anesthesia than those with an audible air leak. Adverse events after the removal of TT were 3.7 times more likely to occur in children whose anesthesia was provided by a less experienced anesthesia trainee., Conclusions: Adverse events after removal of TT were more likely to occur in children with an absent air leak at 25 cmH(2)O pressure and in children whose anesthesia was provided by a less experienced anesthetist.

Two brothers with severe mental retardation of unknown origin were found to share several physical anomalies, including large round head, small concave nose, downslanted palpebral fissures, and gingival hyperplasia. In addition to relative macrocephaly, magnetic resonance imaging (MRI) showed severe cerebral atrophy, especially fronto-temporally. The brothers also had a thin corpus callosum and atrophic caudate nuclei. The reduced white matter showed patchy periventricular signal intensity changes. The lateral and third ventricles were large, but the fourth ventricle was of normal size. The boys had large cisterna magna, communicating widely with the fourth ventricle, but no vermian hypoplasia. Both boys had Lennox-Gastaut spectrum type epilepsy. No chromosomal anomalies were found, despite the suggestive clinical picture. Some of the clinical findings resembled fetal alcohol effects/fetal alcohol syndrome (FAE/FAS), which was also suggested by history. Current diagnostic criteria for FAE/FAS, however, excluded full-blown FAS in these cases and failed to explain the entire clinical picture in the boys. We argue that these boys had an unidentified inherited syndrome, possibly modified by fetal alcohol exposure., (Copyright 2001 Wiley-Liss, Inc.)

Background: The aim of this study was to determine the dose or doses of the new rapid-onset, short-acting, neuromuscular blocking drug rapacuronium that would provide satisfactory conditions for tracheal intubation at 60 s in infants and children., Methods: Sixty-five infants (< 1 yr), 51 younger children (1-6 yr), and 49 older children (7-12 yr) were studied. Anesthesia was induced with thiopental-nitrous oxide-oxygen. Tracheal intubation was attempted 60 s after administration of one of five doses of rapacuronium (0.5, 1.0, 1.5, 2.0, or 2.5 mg/kg) and intubating conditions were assessed using a four-point scale. Following tracheal intubation, anesthesia was maintained with nitrous oxide-oxygen and alfentanil (12.5-50 microg/kg) as necessary. Neuromuscular transmission was monitored in an uncalibrated fashion using an acceleromyograph., Results: Intubating conditions were good or excellent at 60 s in all infants after doses of 1.5 mg/kg or more and in all younger and older children after doses of 2.0 mg/kg or more. The duration of action of rapacuronium was dose- and age-dependent. Mean times to reappearance of the third twitch of the train-of-four (TOF; T3) were less than 10 min in infants at doses of 1.5 mg/kg or less and in younger and older children at doses of 2.0 mg/kg or less. Recovery of T3 after 1.0-2.0 mg/kg rapacuronium was significantly slower in infants compared with younger (P = 0.001) and older (P = 0.02) children. Five adverse experiences were related to rapacuronium administration: Bronchospasm (two instances), tachycardia (one instance), and increased salivation (two instances). None were serious., Conclusions: Doses of 1.5 and 2.0 mg/kg rapacuronium can produce satisfactory intubating conditions at 60 s in anesthetized infants and children, respectively, and are associated with a short duration of action.

Twelve living patients (aged 19 months to 32 years) with aspartylglucosaminuria were examined by magnetic resonance imaging (MRI), and the magnetic resonance (MR) images of 16 health volunteers (aged 4 to 32 years) were used as controls. One patient was examined twice. Postmortem MRI and histopathologic analysis were done on the brains of four additional adult patients. Signal intensities determined quantitatively on T2-weighted images differed significantly between patients and controls, being higher from the white matter (P < .0002) and lower from the thalami (P < .03) in the patients. The generally increased signal intensity of the white matter was most obvious in the young patients, with many focal areas of very high signal intensity in the subcortical white matter. The subcortical white matter showed a somewhat increased signal intensity even at the age of 32 years. In two of the four postmortem MR images, the distinction between the gray and white matter was still poor. At histopathologic analysis, the basic cortical cytoarchitecture was generally preserved but most neurons contained vacuoles, which were also found in the neurons of the deep gray matter. In two of the four autopsy cases the white matter showed diffuse pallor of myelin staining and some gliosis. Thus aspartylglucosaminuria is primarily a gray-matter disease also affecting white matter by delaying myelination.

We studied the efficacy of neostigmine and edrophonium to reverse an atracurium-induced 90% neuromuscular block in 80 paediatric patients anaesthetized with thiopentone, fentanyl and nitrous oxide. The patients were divided into five age groups: 0-2 months, 3-11 months, 2-5 years, 6-10 years, and 11-15 years. At the end of surgery, the neuromuscular block was randomly antagonized with either neostigmine 50 micrograms kg-1 with atropine 20 micrograms kg-1 or with edrophonium 1 mg kg-1 with atropine 10 micrograms kg-1. In general, the first EMG response and train-of-four (TOF) ratio recovered fastest in the youngest age groups following either reversal agent (P < 0.05). However, in each age group edrophonium had a faster onset of effect than neostigmine (P < 0.05) even though a greater TAO-ratio was finally reached with neostigmine. The effects of neostigmine were less variable and more predictable than those of edrophonium. Therefore, we recommend the use of neostigmine for routine paediatric practice.

The goal of this study was to describe a technique which could shorten the time from mivacurium administration to peak neuromuscular block (NMB) after administration of the maximum recommended dose of mivacurium. Forty-eight pediatric patients were randomized into three groups and studied during nitrous oxide-alfentanil-thiopental anesthesia. Every patient received two blinded injections 3 min apart: either 15 micrograms/kg of pancuronium in 1 mL of saline followed by 170 or 200 micrograms/kg of mivacurium or saline followed by 200 micrograms/kg of mivacurium. Intravenous induction of anesthesia followed the first injection. Thenar electromyogram response to supramaximum train-of-four stimulation of the ulnar nerve at 10-s intervals was used for neuromuscular monitoring. Pretreatment with pancuronium significantly shortened the time to NMB and prolonged spontaneous recovery from NMB in comparison to the temporal course of NMB after administration of 200 micrograms/kg of mivacurium. Time from injection to 90% NMB averaged 116 (SEM 11) s after administration of 200 micrograms/kg of mivacurium, and 71 (7) s and 94 (11) s when 200 micrograms/kg or 170 micrograms/kg of mivacurium, respectively, was preceded by pancuronium (P = 0.0095). Mean times from injection to recovery of neuromuscular function to > 25% of baseline (T25) and to train-of-four ratio of 0.75 were 9.1 (0.7) and 15.8 (1.2) min, respectively, after administration of 200 micrograms/kg of mivacurium alone. T25 and train-of-four of 0.75 occurred significantly later at 21.9 (1.8) and 35.0 (2.8) min, respectively (P = 0.0001), when 200 micrograms/kg of mivacurium was preceded by 15 micrograms/kg of pancuronium.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of age on the log-based cumulative dose-response curve of vecuronium was determined in ten age groups of 80 pediatric patients ranging from neonates to adolescents during thiopental-fentanyl-N2O/O2 anesthesia. Neuromuscular block was recorded as the evoked thenar electromyographic response to train-of-four stimulation of the ulnar nerve (2 Hz at 20-second intervals). The dose-response curves were parallel to each other in all ten age groups studied. In neonates and infants, the ED95 of vecuronium was 47 +/- 11 (SD) micrograms/kg. This was significantly lower than the ED95 of 81 +/- 12 micrograms/kg in children between 3 and 10 years of age (P less than 0.01). In patients aged 13 years or older, the ED95 was 55 +/- 12 micrograms/kg, which did not differ from the neonatal and infant values but was significantly lower than the ED95 of children between 3 and 10 years of age. The results indicate that the dose of vecuronium necessary for tracheal intubation is age-dependent. The individual ED95 values varied between 22 and 103 micrograms/kg. This suggests that an individually optimal dose of vecuronium can be administered to pediatric patients only if neuromuscular block is adequately monitored.

The effects of progressive curarization on spontaneous ventilation were studied in 23 patients during light halothane-nitrous oxide-oxygen anaesthesia. In 11 patients, in whom the end-expiratory CO2 concentration and evoked mechanical response were recorded, increasing curarization caused first a slow CO2 accumulation and later an abrupt ventilatory impairment at a twitch tension of between 5 and 50% of original muscle strength. In 12 patients, in whom the evoked integrated hypothenar EMG, spontaneous frontal EMG and mean frequency and amplitude of the EEG were recorded, the spontaneous frontal EMG and ventilation diminished within 3 min, following the first 5 mg dose of tubocurarine. At this stage muscle strength, indicated by the amplitude of the evoked EMG and the train-of-four ratio, was unchanged. Repeated 5 mg doses of tubocurarine caused an almost linear decrease in ventilation and an increase in end-tidal CO2 concentration without affecting the rate of breathing until the sudden impairment of ventilation that occurred usually after the fourth dose of tubocurarine. The EEG changes during curarization were minimal and no common trend was seen. The results suggest that tubocurarine may be given to anaesthetized patients in a dose which is too small to produce, using the evoked EMG, a detectable neuromuscular block, but is sufficient to cause ventilatory depression without a compensatory increase in the rate of breathing.

While monitoring the thenar EMG response to ulnar nerve stimulation, the authors gave either 105, 150, 210, or 300 micrograms/kg of atracurium to 60 patients. The maximal neuromuscular responses were plotted on a log-probit paper. The individual second dose required to produce 95% neuromuscular block (NMB) was estimated from a graph drawn on the paper. The maximal response following this second dose was then plotted. The mean maximal response following the second atracurium dose was 95.5% (SD range, 92.6-97.4%) NMB. The two dose-response points thus acquired resulted in the individual two-dose dose-response curve. The ED50 and ED95 and slope of the two-dose dose-response curve were compared with the single-dose dose-response curve. The average ED50 and ED95 determined by the two-dose and the single-dose techniques were nearly identical [160 micrograms/kg (SD range, 126-201 micrograms/kg) vs. 164 micrograms/kg (SD range, 150-179 micrograms/kg) and 302 micrograms/kg (SD range, 251-363 micrograms/kg) vs. 336 micrograms/kg (SD range, 274-411 micrograms/kg) respectively]. Also, the slopes of the curves were similar [6.2 (SD range, 5.2-7.2) vs. 5.4 (SD range, 4.5-6.4) probit/log]. It is therefore possible to construct an individual dose-response curve for atracurium within 7-9 min and to determine individual pharmacodynamic characteristics of atracurium from this curve.

We compared changes in biopotentials arising from upper facial (FEMG) and abdominal (AEMG) muscles associated with alterations in alveolar enflurane concentration and neuromuscular block. Induction of anaesthesia significantly reduced both FEMG and AEMG mean amplitudes (-60% and -43%, respectively). Neuromuscular blocker-induced abolition of the electrically evoked thenar EMG response did not prevent FEMG and/or AEMG activation during endotracheal intubation. Decreasing the alveolar enflurane concentration was associated with an increase in FEMG amplitude prior to visible signs of arousal in half of the patients. Movement and other signs of inadequate anaesthesia were associated with distinct increases in FEMG amplitude in 29 out of 30 patients. Recovery from neuromuscular block during unchanged alveolar enflurane concentration was associated with increasing amplitudes of both FEMG and AEMG. Finally, very low-amplitude FEMG recordings were always associated with relaxed abdominal muscles.

The antagonistic properties of a mixture of 4-aminopyridine (4-AP) 3 mg X ml-1 and neostigmine 0.2 mg X ml-1 (in three patient groups) administered at 90 per cent d-tubocurarine block were compared with those of plain neostigmine (in three patient groups) in thirty-six patients during thiopentone-fentanyl-nitrous oxide-oxygen anaesthesia. The recovery variables included thumb twitch height, thenar e.m.g. peak-to-peak amplitude, and train-of-four ratio in response to supramaximal ulnar nerve stimulation. In addition, mean arterial pressure, heart rate, apnoea time and time to responsiveness to verbal command after nitrous oxide was turned off at 20 minutes of recovery were examined as circulatory and central nervous system responses to antagonism. The addition of 4-AP 30 mg to neostigmine 2 mg enhanced the recovery of train-of-four ratio from 54.2 +/- 5.2 to 80.2 +/- 5.2 per cent at 20 mins of antagonism (mean +/- SEM; p less than 0.01) while adding 4-AP 45 mg to neostigmine 3 mg increased the train-of-four ratio from 67.7 +/- 2.3 to 92.3 +/- 2.4 per cent (p less than 0.01) when compared with plain neostigmine. No statistically significant difference could be found between the groups in the recovery of twitch height or e.m.g. amplitude. The antagonism of d-tubocurarine block with 4-AP 30 mg plus neostigmine 2 mg was at least as effective as with neostigmine 3-4 mg. Mean arterial pressure increased in the group receiving 45 mg 4-AP plus 3 mg neostigmine.(ABSTRACT TRUNCATED AT 250 WORDS)

The behaviour of spontaneous frontal electromyographic activity (FEMG) was studied during the recovery from suxamethonium and vecuronium block. In order to obtain comparable conditions in the study groups, the duration of the suxamethonium block was prolonged with a suxamethonium infusion. The FEMG was continuously recorded and the evoked electromyographic (EEMG) and twitch tension (ETT) responses were measured every 10 s from the thenar muscles. The median FEMG remained at the base level in 8 of the 12 vecuronium patients, despite a 50% recovery of EEMG. In the suxamethonium group there was an increase in FEMG in all six patients when EEMG had recovered to 10%, and significantly higher FEMG readings were obtained during further recovery from the block. Thus, early recovery of neuromuscular transmission is detected by FEMG more easily when suxamethonium is used instead of vecuronium. The different behaviour of FEMG may reflect a difference in the recovery ratio of ETT/EEMG or in the anaesthetic depth caused by the two types of neuromuscular blockers.

Three clinical methods, visual, tactile and 'spring', for the assessment of neuromuscular blockade were compared to the EMG recording evoked during enflurane anaesthesia and relaxation with vecuronium in 33 patients. During maintenance of the block, the tactile method, based on the recognition of the strength of movement of the patient's thumb against the observer's fingers, was more accurate than the two other methods. The correlation coefficient compared to the TI of the EMG was 0.77. The tactile method led to over-estimation of muscle strength in only 9-10% of the assessments made by the anaesthetists, while this happened in about one-third of the cases when the visual method was applied. The observers under-estimated the muscle power in about 30% of the assessments made with each of the clinical methods. During the recovery, the mean train-of-four (TOF) ratio of the EMG was less than 40% when the anaesthetists announced that they could detect no fade with the visual or tactile methods. The corresponding value obtained with the spring method (standardized preload with a rubber spring) was significantly higher, 66%. Using the spring, a clinically significant residual fade (TOF less than 0.50) could be detected in nine of the 11 cases. As residual relaxation cannot be ruled out using the clinical methods, quantitative recording of neuromuscular function is recommended in cases where complete recovery from muscle relaxation is of special importance. The spring method is the most reliable clinical method during recovery, while the tactile method is the most accurate during the maintenance of neuromuscular block.

The effects of preoperative administration of non-steroidal anti-inflammatory drugs, intraoperative infusion of plasma expanders, type of anaesthesia, blood group and certain coagulation parameters on the bleeding tendency of 354 patients undergoing abdominal and urological surgery were analyzed. The bleeding tendency was estimated by the surgeon at the end of the operation. The preoperative use of non-steroidal anti-inflammatory drugs was associated with an increased bleeding tendency (p less than 0.05). Excessive bleeding was more common in patients who had received dextran intraoperatively, but did not reach statistical significance. Other potential risk factors were not associated with increased bleeding tendency. Two months after the operation, factors VIII:C and vWF:Ag of 32 patients were analyzed. Increased bleeding tendency was not more common in patients with low F VIII activity associated with blood group O, than in others. We conclude that the disorder of primary haemostasis caused by non-steroidal anti-inflammatory drugs is common and causes increased bleeding tendency in surgical patients. If the patient has additional risks of haemostasis, or if accurate surgical haemostasis is of particular importance, it seems justified to withdraw non-steroidal anti-inflammatory drug medication before operation.