Donald D. Vernon

POISONING AND DRUG OVERDOSE

Poisoning is a common cause for intensive care unit admission for both children and adults, and most poisoning victims are effectively treated using standard decontamination measures and supportive care. For a small number of poisons, acceleration of toxin removal with hemodialysis or hemofiltration is indicated. Similarly, specific antidotes are indicated in a few selected circumstances. Rarely, patients may benefit from more aggressive supportive techniques such as cardiopulmonary bypass.

Mortality rates and prognostic variables in children with adult respiratory distress syndrome

In a retrospective chart review of cases of adult respiratory distress syndrome in our pediatric intensive care unit from 1987 to 1990, we attempted to identify the physiologic variables predictive of death. We identified 44 children with adult respiratory distress syndrome; the mortality rate was 75%. We found significant differences between survivors and nonsurvivors in intrapulmonary venous admixture (Qsp/Qt), mean airway pressure (Paw), alveolar-arterial oxygen tension difference (P(A-a)O2), oxygenation index, and peak inspirator pressure; Qsp/Qt greater than 0.5, Paw greater than 23 cm H2O, and P(A-a)O2 greater than 470 mm Hg were 93%, 90%, and 81% predictive of death, respectively, in this study population. Sensitivity and specificity were enhanced when we linked multiple predictors, but this linkage was seldom successful because few patients had more than one positive predictor. We propose to use the individual predictors that we have identified as randomization criteria in a future trial of extracorporeal membrane oxygenation for pediatric cases of adult respiratory distress syndrome.

Effect of Seating Position and Restraint Use on Injuries to Children in Motor Vehicle Crashes

Objective. To determine the effect of restraint use and seating position on injuries to children in motor vehicle crashes, with stratification by area of impact. Methods. Children <15 years old involved in serious automobile crashes in Utah from 1992 through 1996 were identified from statewide motor vehicle crash records. Serious crashes are defined as those resulting in occupant injuries with broken bones or significant bleeding or property damage exceeding

Effect of neuromuscular blockade on oxygen consumption and energy expenditure in sedated, mechanically ventilated children.

750. Probabilistic methods were used to link these records with hospital records. Analysis used logistic regression controlling for age, restraint use, occupant seating position, and type of crash. Results. We studied 5751 children and found 53% were rear seat passengers. More than 40% were unrestrained. Sitting in the rear seat offered a significant protective effect (adjusted odds ratio: 1.7; 95% confidence interval: 1.6–2.0), and restraint use enhanced this effect (adjusted odds ratio: 2.7; 95% confidence interval: 2.4–3.1). Mean hospital charges were significantly greater for front seat passengers. Conclusions. Rear seat position during a motor vehicle crash provides a significant protective effect, restraint use furthers this effect, and usage rates of restraint devices are low. The rear seat protective effect is in addition to and independent of the protection offered from restraints.

Effect of a Pediatric Trauma Response Team on Emergency Department Treatment Time and Mortality of Pediatric Trauma Victims

Objective: To quantify the effects of neuromuscular blockade (NMB) on energy expenditure for intubated, mechanically ventilated, critically ill children. Design: A prospective, unblinded clinical study. Each subject was studied twice, before and after establishment of NMB. Setting: A tertiary care pediatric intensive care unit. Patients: Critically ill children undergoing mechanical ventilation and receiving ongoing sedation were eligible, if they had a cuffed endotracheal tube and were physiologically stable. Interventions: A total of 20 children (age, 1 to 15 yrs) were studied in an unblinded, crossover fashion. All were mechanically ventilated via a cuffed endotracheal tube, with ventilator rate and tidal volume adequate to provide complete ventilation, and FIO2 <0.6. Absence of gas leak around the endotracheal tube was assured, and all patients were sedated using continuous infusions of midazolam and/or fentanyl; no changes in ventilator settings, nutritional input, or inotropic drug dose were permitted during the study period. Each patient underwent indirect calorimetry immediately before establishment of NMB. NMB was then induced, and indirect calorimetry was repeated. Complete blockade was verified using a peripheral nerve stimulator. In each case, the two sets of measurements were completed within a 1‐hr period. Measurements and Main Results: Data analyzed included identifying and diagnostic information, oxygen consumption, and carbon dioxide production. Energy expenditure was calculated using standard formulas. Oxygen consumption and energy expenditure values obtained before and after the establishment of NMB were compared by using paired Students t‐test. NMB reduced oxygen consumption from 6.54 ± 0.49 mL/kg/min to 5.90 ± 0.40 mL/kg/min, and energy expenditure was reduced from 46.5 ± 3.7 kcal/kg/24 hrs to 41.0 ± 2.8 kcal/kg/24 hrs (p < .001 in each case). The reduction in oxygen consumption was 8.7 ± 1.7%, and that in energy expenditure 10.3 ± 1.8%, of pre‐NMB values, respectively. Conclusion: NMB significantly reduces oxygen consumption and energy expenditure in critically ill children who are sedated and mechanically ventilated; the degree of reduction is small.

Management of pediatric trauma

Objective. Delay in the provision of definitive care for critically injured children may adversely effect outcome. We sought to speed care in the emergency department (ED) for trauma victims by organizing a formal trauma response system. Design. A case-control study of severely injured children, comparing those who received treatment before and after the creation of a formal trauma response team. Setting. A tertiary pediatric referral hospital that is a locally designated pediatric trauma center, and also receives trauma victims from a geographically large area of the Western United States. Subjects. Pediatric trauma victims identified as critically injured (designated as “trauma one”) and treated by a hospital trauma response team during the first year of its existence. Control patients were matched with subjects by probability of survival scores, and were chosen from pediatric trauma victims treated at the same hospital during the year preceding the creation of the trauma team. Interventions. A trauma response team was organized to respond to pediatric trauma victims seen in the ED. The decision to activate the trauma team (designation of patient as “trauma one”) is made by the pediatric emergency medicine (PEM) physician before patient arrival in the ED, based on data received from prehospital care providers. Activation results in the notification and immediate travel to the ED of a pediatric surgeon, neurosurgeon, emergency physician, intensivist, pharmacist, radiology technician, phlebotomist, and intensive care unit nurse, and mobilization of an operating room team. Most trauma one patients arrived by helicopter directly from accident scenes. Outcome Measures. Data recorded included identifying information, diagnosis, time to head computerized tomography, time required for ED treatment, admission Revised Trauma Score, discharge Injury Severity Score, surgical procedures performed, and mortality outcome. Trauma Injury Severity Score methodology was used to calculate the probability of survival and mortality compared with the reference patients of the Major Trauma Outcome Study, by calculation ofz score. Results. Patients treated in the ED after trauma team initiation had statistically shorter times from arrival to computerized tomography scanning (27 ± 2 vs 21 ± 4 minutes), operating room (63 ± 16 vs 623 ± 27 minutes) and total time in the ED (85 ± 8 vs 821 ± 9 minutes). Calculation ofz score showed that survival for the control group was not different from the reference population (z = −0.8068), although survival for trauma-one patients was significantly better than the reference population (z = 2.102). Conclusion. Before creation of the trauma team, relevant specialists were individually called to the ED for patient evaluation. When a formal trauma response team was organized, time required for ED treatment of severe trauma was decreased, and survival was better than predicted compared with the reference Major Trauma Outcome Study population.

Inhaled nitric oxide in children with severe lung disease: Results of acute and prolonged therapy with two concentrations

Injury is the number 1 killer of children in the United States. In 2004, injury accounted for 59.5% of all deaths in children younger than 18 years. The financial burden to society of children who survive childhood injury with disability continues to be enormous. The entire process of managing childhood injury is complex and varies by region. Only the comprehensive cooperation of a broadly diverse group of people will have a significant effect on improving the care and outcome of injured children. This statement has been endorsed by the American Association of Critical-Care Nurses, American College of Emergency Physicians, American College of Surgeons, American Pediatric Surgical Association, National Association of Childrens Hospitals and Related Institutions, National Association of State EMS Officials, and Society of Critical Care Medicine.

Enteral methadone to expedite fentanyl discontinuation and prevent opioid abstinence syndrome in the PICU.

OBJECTIVES To evaluate the acute effects of 11 and 60 parts per million (ppm) inhaled nitric oxide on the pulmonary vascular resistance and systemic oxygenation of children with severe lung disease, and to compare the outcome of prolonged therapy with approximately 10 and 40 ppm inhaled nitric oxide. DESIGN Prospective, randomized study. SETTING A 26-bed pediatric intensive care unit in a tertiary childrens hospital. PATIENTS Nineteen patients (median age 11 yrs, range 7 months to 16 yrs) with acute bilateral lung disease requiring a positive end-expiratory pressure (PEEP) of > 6 cm H2O and an FIO2 of > 0.5 for > 12 hrs were treated with inhaled nitric oxide. One patient was treated twice during the same hospitalization. INTERVENTIONS Acute hemodynamic and blood gas effects of 11 and 60 ppm inhaled nitric oxide were studied, while delivering these concentrations in random order for intervals of 20 to 30 mins. Each interval was preceded by an interval of 20 to 30 mins without nitric oxide. Patients were then randomized and treated for a prolonged period with approximately 10 or 40 ppm inhaled nitric oxide independent of their initial acute responses to 11 and 60 ppm. Nitric oxide was discontinued when ventilatory support was decreased to a PEEP of < or = 6 cm H2O and an FIO2 of < or = 0.5. MEASUREMENTS AND MAIN RESULTS Inhaled nitric oxide selectively decreased pulmonary vascular resistance and improved systemic oxygenation. Acute hemodynamic and blood gas effects of 11 and 60 ppm nitric oxide were similar. Systemic oxygenation improved to a greater extent in patients with radiographic evidence of residual aerated lung regions than in patients with diffuse bilateral lung disease. Maximum methemoglobin concentrations were greater in patients treated for a prolonged period with 40 ppm nitric oxide. The mortality and duration of therapy were similar for patients treated with 10 and 40 ppm inhaled nitric oxide. CONCLUSIONS Pulmonary vascular resistance and systemic oxygenation are acutely improved to a similar extent by 11 and 60 ppm inhaled nitric oxide, and concentrations in excess of 10 ppm are probably not needed for prolonged therapy of children with severe lung disease.

Effect of repeal of the national maximum speed limit law on occurrence of crashes, injury crashes, and fatal crashes on Utah highways

Study Objective. To determine if enterally administered methadone can facilitate fentanyl discontinuation and prevent withdrawal in children at high risk for opioid abstinence syndrome.

Prehospital Emergency Care for Children at School and Nonschool Locations

Speed limits were increased in Utah and other States after repeal of the national maximum speed limit law (NMSL) in 1995. This study analyzed effects of the increased speed limit on Utah highways on crash rates, fatality crash rates, and injury crash rates. Annual (1992-1999) rates of crashes, fatality crashes, and injury crashes for the following highway categories were calculated: urban Interstate segments (current speed limit 60-65 miles per hour (mph)); rural Interstate segments (current speed limit 70-75 mph); 55 mph rural non-Interstate highway segments; and high-speed non-Interstate highways (current speed limit 60-65 mph). Data were analyzed using autoregressive integrative moving average intervention time series analysis techniques. There were significant increases in total crash rates on urban (60-65 mph) Interstate segments (confounded by extensive ongoing highway construction on these highways), and in fatal crash rates on high-speed (60-65 mph) rural non-Interstate segments. The following variables were unaffected: total, fatality, and injury crash rates on rural Interstate segments; fatality and injury crash rates on urban Interstate segments; total and injury crash rates on high-speed non-Interstate segments. These results show an adverse effect on crash occurrence for subsets of crash types and highways, but do not show a major overall effect of NMSL repeal and increased speed limit on crash occurrence on Utah highways.