[Mortality in pediatric anesthesia]. / Mortalità in anestesia pediatrica.

UNLABELLED: In last the 50 years many studies have described the causes of mortality. In newborns and infants between 5 and 6 months the risk is higher. The heart is not developed as in older/grown child and these infants need more oxygen than the older ones. Probably, the interaction or interference of positive pressure ventilation with the neonatal circulation is an important cause leading to this pathology. In many studies the authors have identified this risk in the administration of alothane. A more comprehensive literature is needed about sevoflurane in order to know if it is effective. The incidence of complications with an was twice higher than the incidence with a pediatric anesthetists. In the 50s, there have been many changes in our operational METHODS: Actually, we need more randomized and controlled studies to answer the question oh what is the cause of mortality and what we will be able to do in the future to prevent infant mortality in the operation room.

Pulmonary extraction of [3H]bupivacaine: modification by dose, propranolol and interaction with [14C]5-hydroxytryptamine.

The authors studied the single-pass pulmonary extraction of the potent local anesthetic, bupivacaine, in 21 anesthetized rabbits. Pulmonary extraction of [3H]bupivacaine and [14C]5-hydroxytryptamine (5-HT) was quantified from multiple indicator-dilution outflow curves using indocyanine green as the intravascular reference substance. Pulmonary extraction at control (n = 15; mean +/- S.D.) was 81 +/- 6 and 78 +/- 9% for [3H]bupivacaine and [14C]5-HT, respectively. The apparent volume of distribution of bupivacaine was 38 +/- 9 ml/kg compared with 12 +/- 4 ml/kg for indocyanine green. Simultaneous administration of up to 300 micrograms/kg of bupivacaine did not affect the disposition of either radiolabeled amine; however, injection of 1000 micrograms/kg of bupivacaine significantly (P less than .01) depressed pulmonary extraction of both [3H]bupivacaine and [14C]5-HT. In the presence of 1000 micrograms/kg bupivacaine, the apparent volume of distribution of [3H]bupivacaine decreased to 24 +/- 9 ml/kg (P less than .01). Fifteen minutes after administration of propranolol (100-250 micrograms/kg i.v.), [14C]5-HT removal was unchanged, but the pulmonary extraction of [3H]bupivacaine was significantly decreased to 70 +/- 12% (n = 6; P less than .01). These data suggest that bupivacaine is extensively removed as it enters the lung and that the removal process is a combination of passive diffusion and a small component of saturable specific binding. The interaction of bupivacaine with 5-HT may be part of this specific binding (i.e., endothelial cell uptake) or may have been secondary to direct effects of large concentrations of bupivacaine on membrane function.(ABSTRACT TRUNCATED AT 250 WORDS)

Bupivacaine for intercostal nerve blocks in children: blood concentrations and pharmacokinetics.

A pharmacokinetic evaluation of bupivacaine was carried out after intercostal nerve blocks performed on 28 occasions in 27 children varying in age from 3 months to 16 yr. Bupivacaine HCl, 0.5%, with epinephrine 1:200,000 was employed. Doses of 2 mg/kg, 3 mg/kg, and 4 mg/kg resulted in peak whole blood arterial bupivacaine (base) concentrations (mean +/- SD) of 0.77 +/- 0.25 microgram/ml, 1.37 +/- 0.23 microgram/ml, and 1.87 +/- 0.53 microgram/ml, respectively. Calculated pharmacokinetic parameters (mean +/- SD) were the following: apparent volume of distribution (VD beta), 2.8 +/- 0.8 L/kg; steady-state volume of distribution (VDss), 2.7 +/- 0.7 L/kg; elimination half-life (t1/2 beta), 147 +/- 80 min; and total body clearance (Cl), 16.0 +/- 7.4 ml X min-1 X kg-1, or 382 +/- 201 ml X min-1 X m-2. Compared with data reported for adult patients, our data indicate that the volume of distribution is greater and clearance is more rapid in children than in adults. The absorption of local anesthetic from the intercostal space appears to be more rapid in children than adults. In an additional group of 11 children, the relationship of the bupivacaine blood:plasma concentration ratio (lambda) to hematocrit was investigated. Hematocrit in this group ranged from 30 to 59, and lambda varied from 0.47 to 0.82. There was a significant relationship between lambda and hematocrit defined by the equation lambda = -0.0079 Hct + 1.028 (r = 0.72, P less than 0.05). Reporting bupivacaine concentration in terms of plasma concentration may introduce an artifact that is dependent on the hematocrit, and we therefore suggest that whole blood concentration values be reported by investigators in the future.

Bronchial compression by a patent ductus arteriosus associated with pulmonary atresia.

Two infants with pulmonary atresia are presented, wherein a large, vertically oriented patent ductus arteriosus, acting as the only source of pulmonary blood supply, compressed the left bronchus, causing significant respiratory distress. Hyperinflation of the left lung was the clue to this circumstance. After bronchographic confirmation, surgical repair was accomplished by placement of aortopulmonary shunts and division of the patent ductus. Other causes of airway compression in congenital heart disease are briefly reviewed. The embryology of the ductus arteriosus is discussed, emphasizing its anatomic configuration and physiologic role in pulmonary atresia.

Effect of left-to-right, mixed left-to-right, and right-to-left shunts on inhalational anesthetic induction in children: a computer model.

We describe a seven-compartment physiologic model of inhalational anesthetic induction with circulatory shunts that was used to simulate inhalational anesthetic induction in children with congenital heart disease. Our conclusions based on this model are that left-to-right (L-R) shunting has little effect on speed of induction; right-to-left (R-L) shunting significantly slows induction of N2O and halothane anesthesia; and adding an L-R shunt to a preexisting R-L shunt will attenuate the slowing of induction caused by the R-L shunt.

Epiglottitis--duration of intubation and fever.

The present study reviewed the clinical course of 23 pediatric patients with epiglottitis to define criteria for the length of time children require nasotracheal intubation for relief of airway obstruction. All patients had a nasotracheal tube placed in the operating room, were treated with ampicillin or chloramphenicol, and tracheal extubation was performed when the epiglottis was markedly reduced in size to a point where examiners estimated the thickness of the proximal portion of the epiglottis to be 3-4 mm or less. The mean duration of intubation was 36 +/- 14 h (+/- SD), but there was marked variation between patients. There was no significant relationship between reduction in the size of the epiglottis and the febrile nature of the disease. Based on these observations, it would be imprudent to time tracheal extubation by the absence of fever or to establish an arbitrary time period for maintenance of nasotracheal intubation in epiglottis. Direct observation of the epiglottis should determine when airway support is no longer needed.

Somatic evoked potential evaluation of cerebral status in Reye syndrome.

Median nerve somatic evoked potentials (SEPs) were serially recorded in 12 Reye syndrome patients from shortly after admission to discharge. Recovery was clinically satisfactory in nine, unsatisfactory in two, and one died. All SEP components were absent or markedly depressed in initial recordings. Early progressive recovery of primary cortical components was associated with patient survival; lack of it was associated with death. Progressive recovery of SEP components later than 100 msec was associated with satisfactory clinical recovery; failure of recovery of these components was associated with residual neuropsychological deficit. Evaluation of late component recovery required comparison with age-dependent SEP configurations in normal children which differ from adults. We conclude that serial SEP recording is of significant value and superior to the EEG in early prognosis for survival, prognosis for clinically satisfactory or unsatisfactory recovery, and general evaluation of neurologic status in Reye syndrome.

Pediatric intensive care: factors that influence outcome.

Four hundred sixty-one consecutive admissions to the Pediatric Intensive Care Unit (PICU) were evaluated using the Therapeutic Intervention Scoring System (TISS). Patients requiring an increased level of care, defined as TISS points greater than or equal to 10, accounted for 75% of patient days in the ICU. Within this group, the primary reason for admission to the ICU was congenital heart disease, trauma, malignancy, respiratory failure, and sepsis. Survival was inversely related to TISS points, through TISS itself could not differentiate between survivors and nonsurvivors. The mortality rates for children who had a congenital malformation, a cardiac arrest before admission, or who developed acute failure secondary to other disease processes were significantly increased. Comparison of critically ill children and adults using TISS showed mortality rates that were similar. Assuming that the cost of intensive care is related to both seriousness of illness (assessed by TISS) and length of hospitalization, in this pediatric population the cost of hospitalization was not disproportionately high for nonsurvivors compared to survivors. Reduction in mortality rates in a PICU population will be dependent on factors largely uncontrollable buy ICU practitioners. This will come about by reduction in the numbers of congenital malformations and the prevention of childhood trauma.

Alterations in cerebral blood flow in preterm infants with intraventricular hemorrhage.

Xenon-133 inhalation hemispheric cerebral blood flow (HCBF) determinations at one to two days and four to six days postnatally and at 37 weeks postconceptual age have been correlated with computed tomography (CT) scan and autopsy findings in 15 preterm infants weighing less than 1,250 gm at birth. Ten of these infants had germinal matrix hemorrhages (GMH) or intraventricular hemorrhages (IVH). Although HCBF obtained at one to two days showed no mean difference between the GMH/IVH group and the nonhemorrhage infants, hemispheric flow ratios showed significant discrepancies in the GMH/IVH group. In addition, in four of five patients in whom the hemorrhage appeared asymmetric on CT scan, the side of higher flow correlated with the hemorrhage. At four to six days HCBF showed a lower mean value in the GMH/IVH patients than in the nonhemorrhage patients and differences in the interhemispheric ratios in the GMH/IVH group persisted. There were no differences in the mean HCBF values or hemispheric ratios between the two groups of infants at 37 weeks postconceptual age.

Pancreatitis in patients with Reye's syndrome.

Three patients who died of a Reye's syndrome had biochemical or pathological evidence of pancreatitis. None of the 38 survivors had clinical or biochemical evidence of pancreatic dysfunction. The use of hypertonic glucose solutions and exogenous insulin may reverse the metabolic abnormalities seen in Reye's syndrome and may spare the pancreas, thereby preventing the development of pancreatitis. In addition, serum calcium and glucose concentrations appear to correlate with pancreatic function and may be of value in detecting the occurrence of pancreatitis. It is our impression that the development of pancreatitis protends a poor prognosis in patients with Reye's syndrome.