Use of alveolar-arterial gradient as predictor of outcome in respiratory failure.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to J R Custer.
Explore the source record for details and available documents.
The purpose of this study was to determine the frequency of patients with congenital heart disease who were given extracorporeal life support (ECLS) for respiratory failure. Underlying congenital heart disease "masked" by respiratory failure occurred in 2%. The most frequent pre-ECLS diagnosis that "masked" congenital heart disease was persistent fetal circulation. Of neonates with a pre-ECLS diagnosis of persistent fetal circulation, congenital heart disease was found in 56 (9%) of 623 patients.
OBJECTIVES: The purposes of this report are to a) describe the University of Michigan experience with venoarterial or venovenous extracorporeal life support for severe pediatric pulmonary rescue therapy, and b) examine survivors and nonsurvivors for differences that might be useful for examination in future, prospective studies. DESIGN: Case series report. Phase I study of safety and effectiveness of extracorporeal life support for pediatric respiratory failure. SETTING: University of Michigan Medical Center. PATIENTS: Non-neonatal pediatric patients treated with extracorporeal life support for severe respiratory failure at the University of Michigan. INTERVENTIONS: Extracorporeal life support for pulmonary failure. MEASUREMENTS AND MAIN RESULTS: From November 1982 until May 1991, 25 pediatric patients underwent extracorporeal life support for severe pulmonary failure. Twenty patients were treated in the last 36 months. Sixty percent (15/25 patients) survived their life-threatening respiratory illness, were weaned from mechanical ventilation, and were discharged home. The mean patient age was 4.1 yrs, and mechanical ventilation duration before extracorporeal life support was 5.9 days. Mean blood gas data and mechanical ventilation pressures before extracorporeal life support were: peak inspiratory pressure of 48.6 cm H2O, mean airway pressure of 21.9 cm H2O, positive end-expiratory pressure of 9.7 cm H2O, PaCO2 of 43 torr (5.7 kPa), PaO2 of 69 torr (9.1 kPa), estimated alveolar-arterial oxygen gradient of 563 torr (75 kPa), and FIO2 of 0.98. Variables associated with survival included: age of survivors vs. nonsurvivors, 2.1 vs. 7.1 yrs (p less than .02); peak inspiratory pressure of survivors vs. nonsurvivors, 43.1 vs. 57.9 cm H2O (p less than .03); mean airway pressure of survivors vs. nonsurvivors, 18.4 vs. 27.2 cm H2O (p less than .03); and positive end-expiratory pressure of survivors vs. nonsurvivors, 8.1 vs. 12.1 cm H2O (p less than .01). There were no differences detectable in the blood gas values (PaO2, PaCO2, P[A-a]O2) in survivors and nonsurvivors before extracorporeal life support. The number of days mechanical ventilation was used before extracorporeal life support in survivors and in nonsurvivors was similar. CONCLUSION: Extracorporeal life support is an effective rescue therapy for pediatric patients with severe respiratory failure (University of Michigan survival rate of 60%).
OBJECTIVES: To review a large experience with extracorporeal life support in patients with congenital heart disease. To determine the major causes of mortality and morbidity in order to improve the results of using this technology in this patient population. DESIGN: Retrospective chart review. PATIENTS: Twenty-five patients between the ages of 1 day and 8 yrs. These patients had congenital heart disease and were clinically felt to be at high risk for death caused by cardiac failure or by respiratory failure complicated by congenital heart disease. INTERVENTIONS: All patients in this report were placed on extracorporeal life support to allow recovery of myocardial or pulmonary function. MEASUREMENTS AND MAIN RESULTS: Of these 25 patients, 52% were weaned from bypass support and 40% survived to discharge. Patients who were not weaned from extracorporeal life support characteristically suffered from irreversible neurologic injury, multiple organ failure, or bleeding complications. Only one patient died of irreversible cardiac failure. CONCLUSIONS: Extracorporeal life support can be useful in supporting patients with congenital heart disease with life-threatening cardiac or pulmonary failure. Improvements in limiting neurologic and bleeding complications may lead to improvements in the use of extracorporeal life support for this indication. However, prospective, randomized studies are needed to appreciate the role of extracorporeal life support in these patients.
OBJECTIVE: To determine recent morbidity and mortality rates from respiratory syncytial virus infection in a pediatric congenital heart disease population. DESIGN: Retrospective cohort study design. SETTING: The C. S. Mott Children's Hospital, University of Michigan Medical Center. PATIENTS: A total of 740 pediatric patients hospitalized at the University of Michigan Medical Center for symptomatic respiratory syncytial virus infection, of whom, 79 patients had clinically important congenital heart disease. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We retrospectively examined the charts of 740 patients hospitalized at our children's hospital from July 1, 1983 to June 30, 1990 with symptomatic respiratory syncytial virus infection to assess morbidity and mortality outcomes. Seventy-nine patients had congenital heart disease and 40 of these patients had pulmonary hypertension. For the entire cohort and a subset of patients with community-acquired infection, those patients with congenital heart disease had longer durations of hospitalization and greater need for, and days of, both intensive care and mechanical ventilation than patients without congenital heart disease. Mortality risk for respiratory syncytial virus community-acquired infection was not different for congenital heart disease vs. noncongenital heart disease patients (0.0% vs. 0.2%; p = 1.00). When examining only patients with congenital heart disease, those patients with pulmonary hypertension had increased hospital days and greater intensive care and mechanical ventilation durations compared with patients without this diagnosis. The overall mortality rate was low and was equally low for congenital heart disease groups with or without pulmonary hypertension (2.5 vs. 2.6). For community-acquired illness, no mortality was found in either congenital heart disease group. When the cohort of congenital heart disease patients was divided into pre- and postribavirin administration eras, no differences in mean hospital duration, ICU days, and mechanical ventilation days were noted. Of the 79 congenital heart disease patients, only two died during their hospitalization in which respiratory syncytial virus infection occurred. Both patients had nosocomial-acquired respiratory syncytial virus and both were from the postribavirin administration cohort. One of these two patients had received antiviral therapy. Neither death was secondary to respiratory syncytial virus respiratory failure (based on pathologic examination). CONCLUSIONS: We conclude that respiratory syncytial virus mortality risk in pediatric patients with congenital heart disease is less than the risk reported a decade ago. Respiratory syncytial virus infection in congenital heart disease patients with pulmonary hypertension is associated with increased morbidity but not increased mortality rates. The markedly decreased respiratory syncytial virus mortality risk in patients with congenital heart disease currently experienced is likely secondary to improvements in intensive care management and advances in the surgical correction in this population rather than antiviral therapy.
Explore the source record for details and available documents.
OBJECTIVES: To prospectively document the occurrence of ionized hypocalcemia in infants and children treated with extracorporeal membrane oxygenation (ECMO), to determine if the type of calcium salt (calcium chloride or gluconate) used in priming the ECMO circuit affected ionized calcium, to determine if ionized calcium concentrations correlate with total calcium, protein, albumin, or total magnesium values, and to determine if the hypotension usually observed after ECMO initiation correlates with low circulating ionized calcium concentrations. DESIGN: Prospective study. SETTING: Pediatric ICU and neonatal ICU. PATIENTS: Sixteen neonatal and three pediatric patients who were started on ECMO for cardiopulmonary support. INTERVENTIONS: The ECMO circuit was primed in a standardized manner, 100 mg of calcium gluconate was added in group 1 patients and 100 mg of calcium chloride was added in group 2 patients. MEASUREMENTS: Ionized calcium was measured from the circuit before initiation of ECMO and from the patient before, and then 5, 10, 15, 30, 60, 120, and 240 mins after initiation of ECMO. Total calcium and ionized calcium concentrations were measured simultaneously every 6 hrs. Serum total protein, albumin, magnesium, and ionized calcium values were measured from blood samples collected simultaneously twice daily. RESULTS: A significant decrease in the mean serum ionized calcium value occurred 5 mins after the initiation of ECMO in both groups, p less than .001. The ionized calcium value remained significantly decreased until 30 mins after the initiation of ECMO. There were no differences between the ionized calcium concentrations obtained during priming with calcium gluconate vs. those concentrations obtained with calcium chloride priming (p = .79). Throughout the course of ECMO, the serum ionized calcium concentrations ranged from 0.60 to 1.86 mmol/L. Poor correlations existed between circulating ionized calcium values and total calcium (r2 = .30), total protein (r2 = .20), albumin (r2 = .20), and magnesium concentrations (r2 = .10). There was a good correlation between the patients' BP and ionized calcium concentrations after bypass was initiated (r2 = .87). CONCLUSION: Our data demonstrate that ionized hypocalcemia is a frequent occurrence after the initiation of ECMO. Since there is a poor correlation between ionized calcium and total calcium, ionized calcium concentrations should be measured directly in these patients.
The collected data on extracorporeal membrane oxygenation (ECMO), now referred to as extracorporeal life support (ECLS), for pediatric cardiac support has not been analyzed. The purpose of this study was to review the Extracorporeal Life Support (ELSO) Registry data to evaluate the results, identify possible predictors of outcome, and attempt to establish criteria. From 1981 to June of 1990, 189 patients were placed on ECLS for cardiac assist. The age range was 0-204 months (median, 7 months). Mean time on ECLS was 115 +/- 75 hours. Fourteen patients were placed on ECLS as a bridge to transplant or for management of transplant rejection. All of the remaining 175 patients were treated in the postoperative period. The causes of mortality included lack of improvement in cardiovascular function in 69 (37%) of the patients, major central nervous system damage in 28 (15%), uncontrollable hemorrhage in three (2%), sepsis in three (2%), and pulmonary interstitial disease in two (1%). The Registry data were examined for predictors of outcome. There was no significant difference between survivors and nonsurvivors when compared for duration of ECLS, mechanical complications, arterial or venous blood gases, ventilation settings, or hemodynamics. Forty-three percent of 189 pediatric patients treated with ECLS for cardiac failure survived. The highest survival, 61%, occurred in right-sided lesions and the lowest, 18%, in post-Fontan. Mediastinal bleeding, cardiac arrest, renal failure, and prolonged intubation were all associated with a poor outcome. Most deaths were attributed to irreversible cardiac or brain injury, suggesting that results could be improved by earlier identification of high-risk patients and earlier institution of ECLS.
Pulmonary vascular resistance is an important determinant of cardiac output after the Fontan procedure and is adversely affected by elevated mean airway pressure. High-frequency jet ventilation (HFJV) is an alternate form of mechanical ventilation which supports gas exchange at lower mean airway pressure. This study was performed to determine if HFJV could lower mean airway pressure and pulmonary vascular resistance and result in an increase in cardiac output after the Fontan procedure. We prospectively evaluated 13 patients ranging in age from 0.9 to 8.5 years (mean, 3.9 years) and in weight from 6.2 to 20.1 kg (mean, 13.9 kg). Right atrial, left atrial and pulmonary artery catheters were used to measure hemodynamic parameters. Cardiac index was measured by dye dilution technique, and pulmonary vascular resistance was calculated. The patients were stabilized on mechanical ventilation to achieve a PaCO2 = 30 +/- 5 mm Hg, and baseline hemodynamic and respiratory measurements were made. HFJV was begun at settings adjusted to achieve similar gas exchange. Respiratory and hemodynamic measurements were repeated after 30-60 minutes of HFJV. Mechanical ventilation was then resumed at baseline settings, and measurements were repeated 0.5-1 hour later. There was no significant change in gas exchange. HFJV resulted in a 50% reduction in mean airway pressure (9.2 +/- 0.2 cm H2O to 4.6 +/- 0.1 cm H2O, p less than 0.001), a 59% reduction in pulmonary vascular resistance (3.82 +/- 0.36 to 1.52 +/- 0.16 Woods units, p less than 0.001), and a 25% increase in cardiac index (2.32 +/- 0.12 l/min/m2 to 2.91 +/- 0.12 l/min/m2, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
Explore the source record for details and available documents.
Extracorporeal membrane oxygenation is now standard treatment of severe respiratory failure in newborn infants in our center (200 cases) and worldwide (over 2500 cases), but there are few reports of such trials in older children. We reviewed our experience with extracorporeal membrane oxygenation in 33 children aged 1 week to 18 years between 1971 and 1989. The modality was used when all other treatment failed. Extracorporeal membrane oxygenation provided excellent cardiopulmonary support for 1 to 25 days (average 7 1/2 days). The survival rate was 25% for cardiac support patients and 47% for respiratory failure patients (36% overall survival). Mechanical complications included membrane lung failure, tubing rupture, and pump failure, all managed without mortality. Physiologic complications included bleeding, pneumothorax, cardiac arrest, renal failure, hepatic failure, and brain injury. The major cause of death was irreversible injury to lung, heart, or brain. Extracorporeal life support is a reasonable approach for children with serious but reversible cardiopulmonary failure.
Changes in liver shape, position, and uptake of colloid have been noted by us in liver scans in patients following splenectomy. These changes have resulted in confusion in interpretation. Four cases are described to illustrate some of the possible misinterpretations. These include migration of the left lobe of the liver into the left upper quadrant mimicking residual or accessory spleen, mass lesion in the region of the porta hepatis, or recurrent foci of disease.
Explore the source record for details and available documents.