Probabilistic linkage of computerized ambulance and inpatient hospital discharge records: a potential tool for evaluation of emergency medical services.

STUDY OBJECTIVES: Emergency medical services (EMS) is an important part of the health care system. The effect of EMS on morbidity, mortality, and costs of illness is difficult to evaluate because hospital information is not available in out-of-hospital databases. We used probabilistic linkage to create such a database from ambulance and inpatient data and demonstrate the potential for linkage to facilitate evaluation of EMS responses resulting in hospital admission. METHODS: Statewide ambulance and inpatient hospital discharge records were available for 1994 through 1996. Ambulance records indicating admission to the emergency department or hospital (165,649 records) were linked to inpatient hospital records indicating emergency admission (146,292 records) by using probabilistic linkage. Out-of-hospital data (dispatch code, treatments rendered, and ages), linkage rates, and inpatient data (discharge status, charges, length of stay, and payer category) were analyzed. RESULTS: We linked 24,299 (14.7%) ambulance events to inpatient hospital discharges. If we had used exact linkage methods, we would have only linked 14,621 record pairs, a loss of nearly 40%. Linkage rates were relatively constant between years (approximately 15%) but differed by ambulance dispatch codes. Out-of-hospital dispatch codes with high linkage rates included breathing problems (22.6%), chest pain (21.5%), diabetic problems (16.9%), drowning incidents (14.9%), falls (19.2%), strokes (32.8%), and unconsciousness or fainting episodes (16.1%). Linkage to the hospital record provided access to hospital outcome data. Inpatient mortality was 6.8%. Survivors were discharged home (60.7%), transferred to other acute-care facilities (3.6%) or intermediate-care facilities (23.3%), or discharged with home health care provision (4.9%). The median length of stay was 3 days, and median charges were $6,620; total inpatient charges were $286,737,067. CONCLUSION: Probabilistic linkage enables ambulance and hospital discharge records to be linked together and potentially increases our ability to critically evaluate EMS by providing access to hospital-based outcomes. Such evaluation will be further improved by linking to ED, other outpatient, and other public health data sources.

Pharmacokinetics and pharmacodynamics of ranitidine in critically ill children.

OBJECTIVE: To determine the pharmacokinetics and pharmacodynamics of ranitidine in critically ill children and to design a dosage regimen that achieves a gastric pH > or =4. DESIGN: Prospective, open-label, pharmacokinetic-pharmacodynamic study. SETTING: Pediatric intensive care unit in a tertiary care children's hospital. PATIENTS: Mechanically ventilated, critically ill children > or =10 kg who required intravenous ranitidine for stress ulcer prophylaxis. INTERVENTIONS: Ranitidine pharmacokinetics were determined after a single intravenous dose. Gastric pH was monitored hourly via nasogastric pH probe. After the last blood sample, patients received an intravenous bolus of ranitidine (0.5 mg/kg) followed by a continuous infusion (0.1 mg x kg(-1) x hr(-1)). The infusion was increased incrementally (0.05 mg x kg(-1) x hr(-1)) until reaching gastric pH > or =4 for > or =75% of a 24-hr period, after which steady-state plasma concentrations were measured. Plasma concentrations were analyzed by high-pressure liquid chromatography. MEASUREMENTS AND MAIN RESULTS: Twenty-three children (ranging in age from 1.4 to 17.1 yrs) were studied. Pharmacokinetic variables included a clearance of 511.7 +/- 219.7 mL x kg(-1) x hr(-1), volume of distribution of 1.53 +/- 0.99 L/kg, and half-life of 3.01 +/- 1.35 hrs. After the single intravenous dose (1.52 +/- 0.47 mg/kg), gastric pH increased from 1.6 +/- 1.0 to 5.1 +/- 1.1 (p <.001), which was associated with a plasma concentration of 373 +/- 257 ng/mL. Based on the pharmacokinetic variables, the dose of intravenous ranitidine required to target 373 ng/mL as the average steady-state concentration is 1.5 mg/kg administered every 8 hrs. During the continuous infusion, the mean steady-state ranitidine concentration associated with gastric pH > or =4 was 287 +/- 133 ng/mL. This concentration may be achieved with an intravenous loading dose of 0.45 mg/kg followed by a continuous infusion of 0.15 mg x kg(-1) x hr(-1). CONCLUSIONS: The pharmacokinetics of ranitidine in critically ill children are variable. The description of ranitidine's pharmacokinetics and pharmacodynamics in this study may used to design an initial ranitidine dosage regimen that targets a gastric pH > or =4. Thereafter, gastric pH should be monitored and the dose of ranitidine adjusted accordingly.

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

STUDY OBJECTIVE: To determine if enterally administered methadone can facilitate fentanyl discontinuation and prevent withdrawal in children at high risk for opioid abstinence syndrome. DESIGN: Retrospective analysis. SETTING: Pediatric intensive care unit (PICU) in a tertiary care children's hospital. PATIENTS: Twenty-two children (aged 6.1 +/- 5.4 yrs) who received continuous fentanyl infusion for 9 days or longer. INTERVENTION: Guidelines for initiating enteral methadone, rapidly tapering and discontinuing fentanyl infusions, and tapering methadone were implemented in the PICU. Development of opioid abstinence syndrome was evaluated during fentanyl and methadone dosage reductions and for 72 hours thereafter. MEASUREMENTS AND MAIN RESULTS: Children received fentanyl by continuous infusion for 17.8 +/- 8.4 days. Peak fentanyl infusion rate was 5.9 +/- 3.8 microg/kg/hour, and the median cumulative dose was 1302 microg/kg (range 354-7535 microg/kg). Methadone 0.50 +/- 0.22 mg/kg/day was begun 1.6 +/- 1.9 days before tapering fentanyl. The fentanyl infusion rate on starting the taper was 5.0 +/- 3.6 microg/kg/hour. Fentanyl was tapered and discontinued in a median of 2.6 days (range 0-11.9 days). Twenty-one patients had no opioid abstinence syndrome during or after fentanyl taper. One patient experienced significant opioid withdrawal after fentanyl discontinuation, which resolved after reinstitution of fentanyl and increasing the dosage of methadone to 0.3 mg/kg every 6 hours. Overall, methadone was tapered and discontinued in 18.2 +/- 11.9 days without precipitating opioid abstinence syndrome. CONCLUSION: Enteral administration of methadone may expedite fentanyl discontinuation and reduce the risk of withdrawal in critically ill children at high risk for opioid abstinence syndrome.

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

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 F(IO2) <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 Student's 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.

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 $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.

Usage of emergency medical services by children with special health care needs.

OBJECTIVE: To describe the usage of emergency medical services (EMS) by children with special health care needs (CSHCN). METHODS: All EMS runs and related hospital records for children aged 0-17 years in Utah in 1991-92 were linked. The CSHCN status was determined from ICD-9 diagnoses using three available definitions. The amounts of EMS usage were compared between CSHCN and other children. A pediatric intensive care practitioner determined CSHCN status by chart review for 915 children transported by EMS to a pediatric tertiary care hospital, and his classification was compared with the CSHCN status assigned by the three ICD-9-based definitions. RESULTS: The three definitions assigned CSHCN status for 2% to 24% of children using EMS. When compared with other children, CSHCN were more likely to be admitted to the hospital, more likely to use EMS for transfer between health care facilities, and more likely to receive prehospital procedures such as intravenous therapy. In the group of children whose charts were reviewed individually, one ICD-9-based definition most closely agreed to determination of CSHCN status by a pediatric intensive care practitioner. CONCLUSIONS: Children with special health care needs who use EMS are more likely to receive advanced life support service, to receive prehospital procedures, and to be transferred from one health care facility to another. There is need for a specific and measurable definition of CSHCN that can be applied to existing health data.

Prehospital emergency care for children at school and nonschool locations.

OBJECTIVE: The purpose of this study was to ascertain whether school-based emergency medical services (EMS) incidents are different from nonschool-based EMS incidents for school-aged children. METHODS: We examined South Dakota EMS incident reports involving children ages 5 to 18 years old from 1994 through 1996 (n = 12603). Patient characteristics, dispatch reason, primary medical complaint, injury type, contributing factor of injury, and performed interventions were analyzed. RESULTS: During the study period, there were 140455 total EMS incident reports, of which 12603 (9.0%) were for school-aged children. EMS dispatches to a school represented 755 (6.0%) of all EMS incidents for school-aged children. The number of school-based EMS incidents was highest at the beginning of the school year, whereas the number of nonschool-based EMS incidents was highest during the summer months. School-based EMS incidents peaked at noon, whereas nonschool-based EMS incidents peaked after school. For both locations, the average age of the patient was 14 years old. The dispatch reason for school-based EMS incidents differed from those for nonschool-based EMS incidents. The top three school-based EMS dispatch reasons were falls (36.2%), other trauma (27.0%), and medical illness (24.5%). Motor vehicle crashes (30.8%), medical illness (26.2%), and other trauma (11.4%) were the leading nonschool-based EMS dispatch reasons. Injuries accounted for a significantly greater proportion of school-based than nonschool-based EMS incidents (70.7% vs 62.6%). Excluding pain, the most frequent type of injury was a fracture or dislocation in school-based EMS incidents and open soft-tissue injury in nonschool-based EMS incidents. A total of 11 students sustained an injury resulting in paralysis. The body region that was most commonly injured was a lower extremity (23%) in school-based incidents, whereas the head was the most commonly injured body region in nonschool-based incidents (20%). Sports were the largest contributing factor in school-based incidents, whereas alcohol/drug use was the largest contributing factor in nonschool-based EMS incidents among school-aged children. A medical illness was the primary complaint for 206 (27.3%) of the school-based incidents and 3599 (30.4%) of the nonschool-based incidents. The chief medical complaints were breathing difficulty (18.4%), seizure (16%), and other illness (12.3%) for school-based EMS incidents. Other illness (20.0%), breathing difficulty (13.7%), and abdominal pain (12.0%) were the chief complaints for nonschool-based EMS incidents. Treatment was rendered by the EMS provider in 11 753 (93.3%) of the incidents. Frequency of EMS intervention was the same for school-based incidents and nonschool-based incidents. Transportation to a medical facility was more frequent in school-based incidents than nonschool-based incidents. CONCLUSION: Compared with nonschool-based EMS incidents, school-based EMS incidents are more often attributable to injury, more often related to a sports activity, and more often result in transport to a medical facility. Understanding the characteristics of school emergencies resulting in an EMS dispatch may help emergency medical providers be better prepared for school-based incidents. School personnel may benefit from increased knowledge about the EMS system and EMS programs. In addition, EMS incident data may provide useful information about school-based injuries and may provide a means for injury surveillance.

A cost analysis of enterally administered lorazepam in the pediatric intensive care unit.

OBJECTIVE: To determine the cost savings of replacing intravenous midazolam with enterally administered lorazepam in mechanically ventilated children who require long-term continuous sedation. DESIGN: Retrospective review of patients treated according to a preestablished pediatric intensive care unit (ICU) sedation protocol. SETTING: Twenty-six-bed pediatric ICU in a tertiary care children's hospital. PATIENTS: The records of 30 mechanically ventilated children were analyzed. The median age was 1.5 yrs and the median weight was 8.0 kg. Patients required continuous sedation for a total of 16 days (median). INTERVENTIONS: According to our pediatric ICU sedation protocol, midazolam infusion was continued until the hourly midazolam requirement was stable for at least 24 hrs. Thereafter, patients with a nasojejunal tube who were likely to require a minimum of three additional days of continuous sedation were transitioned from intravenous midazolam to enterally administered lorazepam. The goal in transitioning therapy was to titrate the lorazepam dose and reduce midazolam administration while maintaining an unchanged level of sedation. MEASUREMENTS AND MAIN RESULTS: The rate of midazolam administration was significantly (p<.05) reduced beginning on day 1 of lorazepam treatment. Midazolam was successfully discontinued in 24 (80%) patients in 3 days (median), and adequate and appropriate sedation was maintained with lorazepam monotherapy. Six patients in whom midazolam could not be discontinued experienced a 52% reduction in the rate of midazolam administration as a result of adding lorazepam. Total projected midazolam utilization was defined as the sum of midazolam administration before initiating lorazepam and the projected midazolam requirement after initiating lorazepam. Projected midazolam cost was calculated as the product of total projected midazolam utilization and midazolam acquisition cost. Actual expenditures for both midazolam and lorazepam were subtracted from the projected midazolam cost to calculate the estimated cost savings. Overall, midazolam utilization (in milligrams) was reduced by 46.7+/-27.6% (median 52). Total projected midazolam cost for the 30 patients was $90,771. The actual cost of midazolam and lorazepam combined was $47,867, resulting in a cost savings of $42,904. CONCLUSIONS: Transitioning from intravenous midazolam to enterally administered lorazepam in critically ill children who require long-term sedation results in significant cost savings. The oral formulation of lorazepam was convenient to use, inexpensive, and effective in maintaining a continuous and appropriate level of sedation once midazolam was discontinued.

Effect of a pediatric trauma response team on emergency department treatment time and mortality of pediatric trauma victims.

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 of z 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 of z 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.

Pre-hospital emergency medical services: a population based study of pediatric utilization.

OBJECTIVES: To examine emergency medical services (EMS) usage by children in one state. METHODS: Dispatch of an EMS vehicle in response to a call in the US is referred to as a "run". Runs for Utah for 1991-92 were linked to corresponding hospital records. Abbreviated injury severity scores (AISs) were assigned using ICDMAP-90 software. RESULTS: For the two year period there were at least 15 EMS runs per 100 children per year, with incomplete reporting from rural areas. EMS response and scene times were similar for all age groups, but interventions were less frequent for children under 5 years of age. When the principal AIS region of injury was the head, neck, or face, cervical immobilization was less frequent for children less than 5 years of age (54%) than for older children (76%) and immobilization was associated with improved outcome, using the crude measure of lower hospital charges. There was a similar association between splinting of upper extremity fractures and reduced hospital charges. Both associations did not appear to be due to differences in injury severity. CONCLUSIONS: The majority of EMS use by children is for trauma. Children less than 5 years of age are less likely to have an EMS intervention than older children. Whether the lower frequency of interventions is due to the lack of properly sized equipment on the vehicle, or to other factors, is undetermined.

Gastric pH control in critically ill children receiving intravenous ranitidine.

OBJECTIVE: To determine whether the dose of ranitidine recommended in commonly used pediatric drug dosage handbooks (2 to 4 mg/kg/day i.v.) results in successful gastric pH control (pH of >4) in critically ill children. DESIGN: Prospective sample. SETTING: Pediatric intensive care unit in a tertiary care children's hospital. PATIENTS: Fifty consecutive patients who received >24 hrs of scheduled intermittent intravenous ranitidine for stress ulcer prophylaxis were enrolled in the study. Patients with renal or hepatic dysfunction and those who received enteral nutrition through the nasogastric tube were excluded from enrollment. INTERVENTION: Gastric pH was determined at the end of the ranitidine dosing interval, 1 hr after the dose, and at the midpoint between doses. All pH measurements were made from a sample of nasogastric aspirate, using pH sensitive paper. Gastric pH control with ranitidine was considered unsuccessful (poorly controlled) if the pH was <4 for any of the three measurements. MEASUREMENTS AND MAIN RESULTS: Forty-five patients (median age 36 mos; range 2 wks to 264 mos) were included in the analysis. Eighty-two percent of the patients were mechanically ventilated, 16% were pharmacologically paralyzed, 18% required vasoactive infusions, 36% were nourished via transpyloric feeding tubes, and 7% received total parenteral nutrition. Gastric pH was poorly controlled in 36% of patients. Among these patients, the pH at the end of the dosing interval was significantly lower than the pH measured at 1 hr or at the midpoint between doses (p < .05). Seventy-one percent of patients who received <3 mg/kg/day of ranitidine had poor gastric pH control as compared with 19% who received a minimum of 3 mg/kg/day (p< .05). Poor control of gastric pH was not associated with feeding, intubation status, presence of pharmacologic paralysis, use of vasoactive infusions, or age (p > .05). CONCLUSIONS: The minimum ranitidine dose recommended in commonly used pediatric drug references resulted in unsuccessful gastric pH control in a high percentage of pediatric intensive care unit patients. Critically ill children with normal renal and hepatic function should be treated with a minimum 3 mg/kg/day of intravenous ranitidine and the dose should be titrated to a gastric pH of > or =4.

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.

Hemodynamic effects of N-acetylamrinone in a porcine model of group B streptococcal sepsis.

High plasma concentrations of N-acetylamrinone, a primary metabolite of amrinone, are measured in some children during prolonged amrinone infusion. The purpose of this investigation was to determine if N-acetylamrinone has direct hemodynamic effects independent of amrinone. Twenty neonatal piglets received an infusion of 6 x 10(9) colony-forming units/kg of group B Streptococcus to induce sepsis. Subsequently, they were divided into 1 of 3 groups and received a 1-hr infusion of either normal saline (N = 4); 8 mg/kg amrinone, followed by 20 micrograms/kg/min (N = 9); or 8 mg/kg N-acetylamrinone, followed by 20 micrograms/kg/min (N = 7). Hemodynamic measurements and arterial/venous blood-gas determinations were obtained every 30 min during the study. Systemic vascular resistance and pulmonary vascular resistance were calculated. One milliliter of blood was obtained every 30 min during drug administration to determine plasma amrinone and N-acetylamrinone concentrations. The mean amrinone plasma concentrations measured at 30 and 60 min during the infusion time in the group receiving amrinone were 8.8 +/- 1.1 and 6.9 +/- 0.7 micrograms/ml, respectively. These animals experienced a significant decrease in mean pulmonary artery pressure and pulmonary vascular resistance, compared with saline controls after a 30-min infusion of amrinone. The mean N-acetylamrinone plasma concentrations measured at 30 and 60 min during the N-acetylamrinone infusion were 7.3 +/- 0.8 and 5.7 +/- 0.6 micrograms/ml, respectively. There was no difference between any hemodynamic parameter measured in these animals, compared with saline controls at any time during the infusion. We conclude that amrinone, but not N-acetylamrinone, causes pulmonary vasodilation in a porcine model of sepsis and that the parent drug is the sole active component in amrinone.

Fatal air bag mediated craniocervical trauma in a child.

This case report describes a 5-year-old child who sustained fatal craniocervical injuries as the result of an inflating automobile air bag. Although air bags have in general been shown to reduce the severity of injury to occupants of vehicles involved in front-end collisions, a growing number of incidents suggests that in some instances the air bag system itself may cause injuries, some of which can be serious or even fatal. Small children and infants in infant seats travelling in the front passenger seat appear to be particularly at risk. The increasing number of reports of air bag mediated injuries highlights the need for changes in both system design and possibly the threshold speed required for air bag deployment.

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

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 children's 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.

Advances in the critical care of poisoned paediatric patients.

Recent improvements in paediatric intensive care may potentially improve outcome for severely poisoned children. The application of advanced techniques of critical care to the poisoned paediatric patient encompasses a wide variety of therapeutic and technical innovations that are primarily directed towards support of the cardiopulmonary system and removal of toxins. New extracorporeal removal techniques such as continuous arterio-venous haemofiltration have not substantively increased our ability to remove toxins except in rare instances. Exotic techniques such as extracorporeal membrane oxygenation remain in the background for use in rare instances only, with little clear data on the relative risks and benefits of applying them.

Modes of death in the pediatric intensive care unit: withdrawal and limitation of supportive care.

OBJECTIVE: To determine the frequency of withdrawal or limitation of supportive care for children dying in a pediatric intensive care unit (ICU). DESIGN: Retrospective review of medical records. SETTING: Pediatric ICU in a tertiary care children's hospital. PATIENTS: All children dying in the pediatric ICU over a 54-month period (n = 300). INTERVENTIONS: Medical record review. MEASUREMENTS AND MAIN RESULTS: Data recorded for each patient included diagnosis, mode of death, and whether the child was brain dead. Each patient was assigned to one of the following mode of death categories: brain dead; active withdrawal of supportive care (meaning removal of the endotracheal tube); failed cardiopulmonary resuscitation; allowed to die without cardiopulmonary resuscitation (do-not-resuscitate status). A total of 300 patients were identified. Diagnoses included postoperative congenital heart disease (n = 56), head trauma (n = 38), near-miss sudden infant death syndrome (n = 28), pneumonia (n = 22), sepsis (n = 21), near-drowning (n = 21), various anoxic insults (n = 20), multiple trauma (n = 17), and patients with other diagnoses (n = 77). Mode of death was active discontinuation of support in 95 (32%) patients, do-not-resuscitate status in 78 (26%), brain death in 70 (23%), and failed cardiopulmonary resuscitation in 57 (19%). CONCLUSIONS: In a large, multidisciplinary pediatric ICU, the most common mode of death was active withdrawal of support. In addition, more than half (173/300, 58%) of children dying in the pediatric ICU underwent either active withdrawal or limitation (do-not-resuscitate status) of supportive care.