Resource use and health outcomes of paediatric extracorporeal membrane oxygenation.

The use of extracorporeal membrane oxygenation can be rationalised by the assumption that non-zero survival after refractory cardiorespiratory failure represents improved outcome. Survivors may have cognitive and or functional morbidities, require complex ongoing care, and as a consequence consume considerable healthcare resources.

ESPE/LWPES consensus statement on diabetic ketoacidosis in children and adolescents.

Diabetic ketoacidosis (DKA) is the leading cause of morbidity and mortality in children with type 1 diabetes mellitus (TIDM). Mortality is predominantly related to the occurrence of cerebral oedema; only a minority of deaths in DKA are attributed to other causes. Cerebral oedema occurs in about 0.3-1% of all episodes of DKA, and its aetiology, pathophysiology, and ideal method of treatment are poorly understood. There is debate as to whether physicians treating DKA can prevent or predict the occurrence of cerebral oedema, and the appropriate site(s) for children with DKA to be managed. There is agreement that prevention of DKA and reduction of its incidence should be a goal in managing children with diabetes.

Mechanical circulatory support for the treatment of children with acute fulminant myocarditis.

BACKGROUND: Viral myocarditis may follow a rapidly progressive and fatal course in children. Mechanical circulatory support may be a life-saving measure by allowing an interval for return of native ventricular function in the majority of these patients or by providing a bridge to transplantation in the remainder. METHODS: A retrospective chart review of 15 children with viral myocarditis supported with extracorporeal membrane oxygenation (12 patients) or ventricular assist devices (3 patients) was performed. RESULTS: All patients had histories and clinical findings consistent with acute myocarditis. The median age was 4.6 years (range 1 day-13.6 years) with a median duration of mechanical circulatory support of 140 hours (range 48-400 hours). Myocardial biopsy tissue demonstrated inflammatory infiltrates or necrosis, or both, in 8 (67%) of the 12 patients who had biopsies. Overall survival was 12 (80%) of 15 patients, with 10 (83%) survivors of extracorporeal membrane oxygenation and 2 (67%) survivors of ventricular assist device support. Nine (60%) of the 15 patients were weaned from support, with 7 (78%) survivors; the remaining 6 patients were successfully bridged to transplantation, with 5 (83%) survivors. All survivors not undergoing transplantation are currently alive with normal ventricular function after a median follow-up of 1.1 years (range 0.9-5.3 years). CONCLUSION: Eighty-percent of the children who required mechanical circulatory support for acute myocarditis survived in this series. Recovery of native ventricular function to allow weaning from support can be anticipated in many of these patients with excellent prospects for eventual recovery of full myocardial function.

Outcomes for children with cardiomyopathy awaiting transplantation.

OBJECTIVE: To determine factors associated with outcomes after listing for transplantation in children with cardiomyopathies. BACKGROUND: Childhood cardiomyopathies form a heterogeneous group of diseases, and in many, the prognosis is poor, irrespective of the etiology. When profound heart failure develops, cardiac transplantation can be the only viable option for survival. METHODS: We included all children with cardiomyopathy listed for transplantation between 12/89 and 4/98 in this historical cohort study. RESULTS: We listed 31 patients, 15 male and 16 female, 27 with dilated and 4 with restrictive cardiomyopathy, for transplantation. The median age at listing was 5.7 years, with a range from fetal life to 17.8 years. Transplantation was achieved in 23 (74%), with a median interval from listing of 54 days, and a range from zero to 11.4 years. Of the patients, 14 were transplanted within 30 days of listing. Five patients (16%) died before transplantation. Within the Canadian algorithm, one of these was in the third state, and four in the fourth state. One patient was removed from the list after 12 days, having recovered from myocarditis, and two remain waiting transplantation after intervals of 121 and 476 days, respectively. Patients who died were more likely to be female (5/5 vs. 11/26; p=0.04) and to have been in the third or fourth states at listing (5/5 vs. 15/26; p=0.04). The use of mechanical ventricular assistance, in 10 patients, was not a predictor of an adverse outcome. While not statistically significant, survival to transplantation was associated with treatment using inhibitors of angiotensin converting enzyme, less mitral regurgitation, a higher mean ejection fraction and cardiac index, and lower right ventricular systolic pressure. CONCLUSIONS: Children with cardiomyopathy awaiting transplantation have a mortality of 16% related to their clinical state at the time of listing.

Negative pressure ventilation via chest cuirass to decrease ventilator-associated complications in infants with acute respiratory failure: a case series.

Pulmonary and nonpulmonary complications of invasive positive pressure ventilation are well documented in the medical literature. Many of these complications may be minimized by the use of noninvasive ventilation. During various periods of medical history, negative pressure ventilation, a form of noninvasive ventilation, has been used successfully. We report the use of negative pressure ventilation with a chest cuirass to avoid or decrease the complications of invasive positive pressure ventilation in three critically ill infants at two institutions. In each of these cases, chest cuirass ventilation improved the patient's clinical condition and decreased the requirement for more invasive therapy. These cases illustrate the need for further clinical evaluation of the use of negative pressure ventilation utilizing a chest cuirass.

Influence of perioperative factors on outcomes in children younger than 18 months after repair of tetralogy of Fallot.

BACKGROUND: There has been a trend toward advocating earlier repair of tetralogy of Fallot and avoiding palliative procedures. The impact of this trend on perioperative outcomes has not been adequately documented. METHODS: Data from consecutive patients undergoing repair of tetralogy of Fallot at less than 18 months of age from May 1987 to September 1994 were reviewed. Independent factors associated with duration of stay in the intensive care unit were sought. RESULTS: Repair was performed in 89 infants at a median age of 13 months (range, 15 days to 18 months). A systemic-pulmonary artery shunt was present in 24% of patients. Mean duration of cardiopulmonary bypass was 119+/-37 minutes; 63% of patients received a transannular patch. There were six deaths (7%), all occurring less than 48 hours after repair. The median duration of stay in the intensive care unit was 5 days (range, 1 day to 8 months). Significant independent factors associated with increasing length of intensive care unit stay included younger age at repair, previous shunt, malformation syndrome, increased total dose and number of inotropic agents used, and respiratory complications. Hemodynamic variables serially recorded in the first 48 hours after repair were independently associated with death or prolonged (>7 days) duration of stay. CONCLUSIONS: Although outcomes after repair of tetralogy of Fallot in infants are good, both younger age at repair and previous palliative procedures were associated with longer duration of stay in the intensive care unit.

High-frequency oscillatory ventilation in pediatric respiratory failure: a multicenter experience.

OBJECTIVE: The use of high-frequency oscillatory ventilation (HFOV) has increased dramatically in the management of respiratory failure in pediatric patients. We surveyed ten pediatric centers that frequently use high-frequency oscillation to describe current clinical practice and to examine factors related to improved outcomes. DESIGN: Retrospective, observational questionnaire study. SETTING: Ten tertiary care pediatric intensive care units. PATIENTS: Two hundred ninety patients managed with HFOV between January 1997 and June 1998. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were classified according to presence or absence of preexisting lung disease, symptomatic respiratory syncytial virus infection, or presence of cyanotic heart disease or residual right-to-left intracardiac shunt. In addition, patients for whom HFOV acutely failed were analyzed separately. Those patients with preexisting lung disease were significantly smaller, had a significantly higher incidence of pulmonary infection as the triggering etiology, and had a significantly greater duration of conventional ventilation before institution of HFOV compared with patients without preexisting lung disease. Stepwise logistic regression was used to predict mortality and the occurrence of chronic lung disease in survivors. In patients without preexisting lung disease, the model predicted a 70% probability of death when the oxygenation index (OI) after 24 hrs was 28 in the immunocompromised patients and 64 in the patients without immunocompromise. In the immunocompromised patients, the model predicted a 90% probability of death when the OI after 24 hrs was 58. In survivors without preexisting lung disease, the model predicted a 70% probability of developing chronic lung disease when the OI at 24 hrs was 31 in the patients with sepsis syndrome and 50 in the patients without sepsis syndrome. In the patients with sepsis syndrome, the model predicted a 90% probability of developing chronic lung disease when the OI at 24 hrs was 45. CONCLUSIONS: Given the number of centers involved and the size of the database, we feel that our results broadly reflect current practice in the use of HFOV in pediatric patients. These results may help in deciding which patients are most likely to benefit from aggressive intervention by using extracorporeal techniques and may help identify high-risk populations appropriate for prospective study of innovative modes of supporting gas exchange (e.g., partial liquid breathing or intratracheal pulmonary ventilation).

Clinical outcomes of acute myocarditis in childhood.

OBJECTIVE: To describe clinical outcomes of a paediatric population with histologically confirmed lymphocytic myocarditis. DESIGN: A retrospective review between November 1984 and February 1998. SETTING: A major paediatric tertiary care hospital. PATIENTS: 36 patients with histologically confirmed lymphocytic myocarditis. MAIN OUTCOME MEASURES: Survival, cardiac transplantation, recovery of ventricular function, and persistence of dysrhythmias. RESULTS: Freedom from death or cardiac transplantation was 86% at one month and 79% after two years. Five deaths occurred within 72 hours of admission, and one late death at 1.9 years. Extracorporeal membrane oxygenation support was used in four patients, and three patients underwent heart replacement. 34 patients were treated with intravenous corticosteroids. In the survivor/non-cardiac transplantation group (n = 29), the median follow up was 19 months (range 1.2-131.6 months), and the median period for recovery of a left ventricular ejection fraction to > 55% was 2.8 months (range 0-28 months). The mean (SD) final left ventricular ejection and shortening fractions were 66 (9)% and 34 (8)%, respectively. Two patients had residual ventricular dysfunction. No patient required antiarrhythmic treatment. All survivors reported no cardiac symptoms or restrictions in physical activity. CONCLUSIONS: Our experience documents good outcomes in paediatric patients presenting with acute heart failure secondary to acute lymphocytic myocarditis treated with immunosuppression. Excellent survival and recovery of ventricular function, with the absence of significant arrhythmias, continued cardiac medications, or restrictions in physical activity were the normal outcomes.

Nosocomial infection following cardiovascular surgery: comparison of two periods, 1987 vs. 1992.

OBJECTIVE: To evaluate whether changes have occurred at our center in the rate of nosocomial infections and in the infectious organisms consequent to changes in policy and procedure as of 1987. SETTING: Multidisciplinary pediatric intensive care unit (PICU) in a major tertiary care center. DESIGN: Prospective comparative study. PATIENTS: Four-hundred and fifty-five consecutive patients who underwent cardiac surgery within a 10-month period. INTERVENTIONS: Changes related to antibiotic use and invasive device management were introduced after the 1987 survey. To determine the effect of these changes, all patients undergoing cardiac surgery between July 1991 and April 1992 were followed daily from PICU admission to 2 months after hospital discharge for signs of infection. Each infectious episode was reviewed by the nosocomial infection control committee. A weighted scoring system was used to determine risk. MEASUREMENTS AND MAIN RESULTS: In the 1987 study, 40 of 310 patients had 78 infections for a nosocomial infection ratio (NIR) of 25.2. Of the 455 patients surveyed in 1992, 72 had 91 episodes of infection. The nosocomially infected patient rate was 15.8 and the NIR was 20. The frequency of wound infection decreased from 7% in 1987 to 4.3% in this study, and no episode of mediastinitis was observed. In the bacteriological spectrum, the absence of candidal infection was significant, and there was a decrease in the proportional frequency of pseudomonas infection from 21% to 15%. CONCLUSION: The comparison between the two time periods demonstrates that an aggressive approach to managing intravascular catheters and urinary catheters and limiting the use of antibiotics probably affects the spectrum of nosocomial infections.

Attenuation of ventilator-induced acute lung injury in an animal model by inhibition of neutrophil adhesion by leumedins (NPC 15669).

OBJECTIVES: Beta2-integrin (CD11b/CD18) expression, an indicator of neutrophil activation, has been associated with the development of acute respiratory distress syndrome. Leumedins act directly on leukocytes to inhibit the up-regulated expression of beta2-integrins involved in leukocyte adhesion. We examined the effect of such a new anti-inflammatory agent, NPC 15669 (N-[9H-(2,7-dimethylfluorenyl-9-methoxy)-carbonyl]-L-leucine), on neutrophil-mediated acute lung injury in an animal model. DESIGN: Prospective, randomized, blinded, controlled animal study. SETTING: An animal laboratory in a university setting. SUBJECTS: Adult New Zealand rabbits. INTERVENTIONS: After repeated lung lavages with normal saline to induce acute lung injury, anesthetized rabbits were randomly assigned to one of two groups (n = 6 per group): a) treatment group (pretreated with NPC 15669 [10 mg/kg i.v. bolus] 30 mins before lavage, followed by a continuous infusion [5 mg/kg/hr] for the duration [4 hrs] of the experiment); or b) control group (pretreatment and continuous infusion with placebo). All animals were mechanically ventilated with identical pressure settings over 4 hrs and were killed at the end of the experiment. MEASUREMENTS AND MAIN RESULTS: PaO2, PaCO2, and tidal volumes were repeatedly measured and airway pressure settings were noted every 30 mins. At the end of the experiment, lungs were taken out for measurements of the myeloperoxidase content, for conventional histology (hematoxylin and eosin staining), and for intracellular adhesion molecule-1 immunohistostaining. Pretreatment with NPC 15669 profoundly improved oxygenation from a PaO2 of 52 +/- 5 torr (6.9 +/- 0.7 kPa) to 250 +/- 161 torr (33.3 +/- 21.5 kPa) within 60 mins after lung lavage (p < .05). Oxygenation continued to improve throughout the study, reaching a maximal PaO2 value of 395 +/- 98 torr (52.7 +/- 13.1 kPa) at 4 hrs. In the control group, oxygenation remained poor throughout the observation period. PaO2 values differed significantly (51 +/- 20 torr [6.8 +/- 2.7 kPa] vs. 306 +/- 126 torr [40.8 +/- 16.8 kPa], p < .005) at 90 mins and at all subsequent measurements from those values in the NPC 15669 group. Dynamic lung compliance improved significantly 60 to 90 mins after repeated lung lavage. Histology demonstrated markedly less lung damage (hyaline membrane formation and leukocyte infiltration) in treated animals (p < .05) than in controls. CONCLUSIONS: NPC 15669 seems to block inflammatory reactions by inhibiting the sequestration of neutrophils in acute, ventilator-associated lung injury. As a result, gas exchange and total lung compliance improve. Application of this and similar compounds affecting neutrophil adhesion warrants further investigation as a treatment modality for acute lung injury.

Postnatal management of congenital diaphragmatic hernia.

The emphasis in postnatal management has shifted from the neonatal surgical emergency approach to strategies designed to deal with pulmonary hypoplasia and the pulmonary vascular abnormalities. There has been extensive experience with alternative ventilation strategies such as ECMO and high frequency ventilation, without there being convincing evidence that these have had a major impact on mortality. Strategies that emphasize the importance of minimizing ongoing lung injury, such as pressure limited (permissive hypercapnia) ventilation and the use of surfactant replacement therapy, are beginning to show some encouraging results.

The effect of single-dose and continuous skeletal muscle paralysis on respiratory system compliance in paediatric intensive care patients.

OBJECTIVE: To investigate the effect of single dose and continuous skeletal muscle paralysis on respiratory system compliance in 53 paediatric intensive care patients. DESIGN: Prospective clinical study. SETTING: Multidisciplinary paediatric intensive care unit. PATIENTS: Twenty-three children ventilated for acute pulmonary pathology, and 30 ventilated for isolated intracranial pathology, who initially had normal lungs. INTERVENTIONS: The 23 patients with acute pulmonary pathology received a single dose of muscle relaxant to facilitate diagnostic procedures. Fifteen patients with isolated intracranial pathology received continuous skeletal muscle paralysis for longer than 24 h, and the other 15 received no paralysis. MEASUREMENTS AND RESULTS: Respiratory system compliance deteriorated by 14% from 0.519 +/- 0.2 to 0.445 +/- 0.18 ml cmH2O-1 kg-1 (p < 0.001) following a single dose of muscle relaxant in the 23 patients with acute pulmonary pathology. In the 15 with isolated intracranial pathology who received continuous skeletal muscle paralysis there was a progressive deterioration in compliance, which reached 50% of the initial compliance by day 4 of paralysis (p < 0.001) and improved back to normal following discontinuation of paralysis. There were no changes in compliance in the 15 patients with isolated intracranial pathology who were ventilated but not paralysed. The paralysed patients required mechanical ventilation longer than the non-paralysed patients (p < 0.001), and 26% of these patients developed nosocomial pneumonia (p = 0.03), a complication that was not seen in the non-paralysed patients. CONCLUSIONS: Skeletal muscle paralysis results in immediate and progressive deterioration of respiratory system compliance and increased incidence of nosocomial pneumonia. The benefits of paralysis should be balanced against the risks of deteriorating pulmonary function.

Increased respiratory system resistance and bronchial smooth muscle hypertrophy in children with acute postoperative pulmonary hypertension.

Following surgery for congenital heart disease, there is often an increased reactivity of the pulmonary vasculature to stimuli, resulting in rapid increases in pulmonary artery pressure and a clinical impression of stiff lungs. Lung mechanics were measured in 30 children, mean age 6.7 +/- 4.1 mo, who were ventilated and had pulmonary artery pressure monitoring following surgery for congenital heart disease. A group of 15 patients developed postoperative pulmonary hypertension. In these patients, respiratory system resistance was 43% higher (p = 0.001) and compliance 11% lower (p = 0.004) during acute pulmonary hypertension compared with baseline pulmonary artery pressure. No changes in resistance or compliance were seen in the 15 patients who did not develop pulmonary hypertension. The changes in lung mechanics interfered with mechanical ventilation, resulting in a 9.4% rise in PaCO2 during pulmonary hypertension. The bronchial smooth muscle was found to be increased by 68%, and the vascular smooth muscle was more than twice normal in lung biopsies from 9 pulmonary hypertension patients compared with 6 age-matched postmortem controls patients who had no cardiac or pulmonary disease. The bombesin-immunoreactive pulmonary neuroendocrine cells (PNEC) were also increased in the pulmonary hypertension patients. These findings suggest a coconstriction and cohypertrophy of bronchial and vascular smooth muscle during pulmonary hypertension. Mediators, such as bombesin, endothelin-1, and serotonin, are known to be produced by PNEC and may be involved in the observed vasoconstriction, increased respiratory system resistance, and smooth muscle hypertrophy.

Profile of paediatric patients with pulmonary hypertension judged by responsiveness to vasodilators.

OBJECTIVE: To describe the demographic and haemodynamic variables of children presenting with primary pulmonary hypertension or pulmonary hypertension appearing or persisting after surgical correction of congenital heart defects and to assess the acute effect of vasodilator drugs on their pulmonary vascular bed. DESIGN: Retrospective review. SETTING: Paediatric cardiology department and intensive care unit of a large tertiary centre. PATIENTS: Fourteen consecutive patients presenting with primary pulmonary hypertension (group 1) or pulmonary hypertension persisting or appearing late after complete surgical repair (group 2). INTERVENTION: Baseline haemodynamic measurements were taken in room air at rest and repeated in 100% oxygen. With constant monitoring of heart rate and pulmonary and systemic arterial pressures, patients were given serial intravenous, sublingual, or oral incremental doses of vasodilators (mean 4.1 trials per patient). The maximum effect of the drug was charted. MAIN OUTCOME MEASURES: A positive response to acute vasodilator tests was defined as a decrease in mean pulmonary or mean systemic arterial pressure > 15% with the mean pulmonary artery pressure not reaching the systemic level and either no change or an increase in mean systemic arterial pressure. Haemodynamic variables between groups (1 v 2, responders v non-responders, patients experiencing or not experiencing adverse effects to vasodilators) were compared by a two tailed unpaired Student's t test, and their survival curves were compared by the log rank statistic. RESULTS: Groups are small and definitive conclusions are difficult to draw, but the baseline haemodynamic assessments were not significantly different between group 1 and 2 or between responders and non-responders to vasodilators. Patients experiencing adverse effects had a higher pulmonary vascular resistance (p = 0.04) and wedge pressure (p = 0.02) than those without adverse effects. Of the vasodilators used, tolazoline, hydralazine, salbutamol, phentolamine, and phenoxybenzamine were ineffective. A positive response was seen in five of 13 patients given oxygen, in one of eight given prostacyclin, four of 12 given nifedipine, four of eight given diltiazem, one of six given captopril, and two of seven given glyceryl trinitrate. Estimates of survival of the population with primary pulmonary hypertension were 37% at one year and 12% at 2.5 years. Survival was significantly shorter in the non-responders than in the responders (p = 0.005). CONCLUSION: Children with primary pulmonary hypertension present to the cardiologist at a young age (five of eight were younger than 7 years) but with advanced pulmonary vascular disease and have a poor prognosis. 64% of group 1 and group 2 patients had a positive response to acute treatment with at least one vasodilator. Calcium channel blockers were the most effective agents. There was a positive response to drugs despite a negative response to acute treatment with oxygen. The survival of non-responders was shorter than that of the responders.

Fatal bicycle accidents in children: a plea for prevention.

We reviewed the coroner's records of all fatal bicycle accidents occurring in children (aged 0 to 15 years) in Ontario (pediatric population, 2,007,230) between January 1, 1985 and December 31, 1989. The injuries sustained were documented and scored with anatomical injury scores (Abbreviated Injury Score 1985 and Injury Severity Score) and categorized as unsurvivable or survivable. The causes and circumstances were documented from police accident reports. Eighty-one deaths resulted from bicycle accidents, an annual mortality rate of 1.44 deaths per 100,000 children per year. In 74 (91%) of these cases the injuries were deemed unsurvivable, 89% of which were head injuries. Seventy-eight (96%) of the deaths resulted from collisions with motor vehicles. No victim was wearing a helmet at the time of injury. In 70% of the deaths, the cyclist was considered to have caused the collision, either because of a violation of a road traffic law or poor road sense. These findings suggest that more emphasis should be placed on primary and secondary injury prevention by such methods as bicycle safety education for children and the promotion of bike helmet use. In addition, in view of the high incidence of unsurvivable head injury, the introduction of legislation requiring the use of protective helmets should be considered.

Continuous arteriovenous hemofiltration after cardiac operations in infants and children.

Acute renal insufficiency after cardiopulmonary bypass can lead to a significant morbidity from fluid overload and electrolyte disturbance, impede pulmonary gas exchange, and postpone weaning from mechanical ventilation. The limitations placed on free water intake result in severe restriction of nutrition while diuretic therapy causes electrolyte imbalance. Artificial renal support either in the form of peritoneal dialysis or hemodialysis may be complicated by sepsis and hemodynamic instability. We reviewed our experience with the use of continuous arteriovenous hemofiltration, an extracorporeal technique for removal of solutes, toxins, and water in critically ill patients with cardiac failure complicated by acute renal insufficiency and hemodynamic instability after cardiopulmonary bypass. Ten infants and children with renal insufficiency caused by low cardiac output had continuous arteriovenous hemofiltration instituted for indications including sepsis, volume overload, oliguria for more than 24 hours nonresponsive to diuretic therapy, and the need for hyperalimentation. All were supported by mechanical ventilation and receiving high-dose inotropic support. Arterial and venous vascular access was successfully obtained by cannulation of the femoral artery and vein in nine patients. Anticoagulation of the circuit was achieved with heparin infusion (6 to 20 micrograms/kg/hr) and monitored by measurement of activated clotting time. The continuous arteriovenous hemofiltration circuit was replaced if there was clot formation, or at 3 days after placement. Dialysis solution (Dianeal) 1.5% or 0.5% was infused as prefilter dilution. With the use of continuous arteriovenous hemofiltration, 20 to 100 m/hr of ultrafiltrate was removed, which allowed correction of hypervolemia, and caloric intake increased from 13.5 kcal/kg/day to 79.5 kcal/kg/day. Continuous arteriovenous hemofiltration was maintained between 5 hours and 8 days and was well tolerated in all patients. Serum urea and creatinine levels declined during continuous arteriovenous hemofiltration. We conclude that continuous arteriovenous hemofiltration is a safe and effective method for fluid and electrolyte homeostasis and that it thus allows hyperalimentation in infants and children after cardiac operations.

Comparison of continuous versus intermittent furosemide administration in postoperative pediatric cardiac patients.

OBJECTIVE: To compare the effects of furosemide administered by intermittent iv infusion vs. continuous iv infusion on urine output, hemodynamic variables, and serum electrolyte concentrations. DESIGN: Prospective, randomized trial. SETTING: Pediatric ICU. PATIENTS: Postoperative pediatric cardiac patients. INTERVENTIONS: Patients were assigned to either the continuous iv infusion or the intermittent infusion groups. The intermittent group received 1 mg/kg iv of furosemide every 4 hrs to be increased by 0.25 mg/kg iv every 4 hrs to a maximum of 1.5 mg/kg iv if the urine output was less than 1 mL/kg.hr. The continuous infusion group received an initial furosemide dose of 0.1 mg/kg iv (minimum 1 mg) followed by an iv infusion rate of 0.1 mg/kg.hr of furosemide to be doubled every 2 hrs to a maximum of 0.4 mg/kg.hr if the urine output was less than 1 mL/kg.hr. MEASUREMENTS AND MAIN RESULTS: Demographic variables, fluids, electrolyte and inotropic requirements were the same in both groups. A significantly (p = .045) lower daily dose of furosemide (4.90 +/- 1.78 vs. 6.23 +/- 0.62 mg/kg.day) in the continuous iv infusion group produced the same 24-hr urine volume as that of the intermittent group. There was more variability in urine output in the intermittent group as well as more urinary losses of sodium (0.29 +/- 0.15 vs. 0.20 +/- 0.06 mmol/kg.day, p = .0007) and chloride (0.40 +/- 0.20 vs. 0.30 +/- 0.12 mmol/kg.day, p = .045). CONCLUSION: Furosemide administered by continuous iv infusion is advantageous in the post-operative pediatric patient because of a more controlled and predictable urine output with less drug requirement and less urinary loss in sodium and chloride.

Efficacy, results, and complications of mechanical ventilation in children with status asthmaticus.

We have conducted a retrospective survey of 79 children out of a total hospital asthmatic patient population of 2,412, admitted over a 32 month period to the ICU for the management of severe status asthmaticus. All patients were in severe respiratory distress with CO2 retention; 19 required mechanical ventilation due to increasing fatigue and worsening bronchospasm, having failed to respond to either inhaled or IV bronchodilator therapy. All patients were ventilated at slow rates (less than 12 min) and their airway pressure (Paw) was deliberately kept below 45 cmH2O, while accepting a PaCO2 in the 45-60 mmHg range, as long as the pH was compensated. Although two patients developed pneumothoraces while on positive pressure ventilation, these were resolved without incidents. Five patients who had mediastinal or subcutaneous air leaks prior to intubation did not develop pneumothoraces. Following the initiation of mechanical ventilation, IV beta-agonist therapy was increased in order to reverse the bronchospasm and reduce the duration of mechanical ventilation. Mean duration of intubation was 42 hours. Fourteen of the 19 patients were weaned and extubated within 48 hours. All patients survived without sequelae. We conclude that a degree of controlled "hypoventilation" by deliberately choosing Paw less than 45 cmH2O can be successfully used to ventilate children with severe status asthmaticus with a reduced rate of pressure-related complications.

Unsuspected diaphragmatic hernia: a potential cause of sudden and unexpected death in infancy and early childhood.

Congenital diaphragmatic hernias are usually found in neonates who present with respiratory distress. However, a significant number may remain clinically undiagnosed until much later in life. Of interest, the prognosis is felt to be better in this latter group. We describe three previously well patients (aged 2, 4, and 24 months) who suffered unexpected cardiorespiratory arrests due to unsuspected congenital diaphragmatic defects with intestinal herniation. Deaths resulted from cardiovascular and respiratory compromise due to visceral herniation that caused mediastinal and pulmonary compression.