Alfred L Gest

Percutaneous Central Catheters and Peripheral Intravenous Catheters Have Similar Infection Rates in Very Low Birth Weight Infants

OBJECTIVE:We performed this study to determine if percutaneous central lines (PCLs) were associated with infection more often than peripherally placed intravenous catheters (PIVs).STUDY DESIGN:We conducted a retrospective, cohort study of 53 infants with PCLs inserted from March 1993 to February 1995 for evidence of catheter-related bloodstream infection and 97 cohorts with PIVs who were matched to the infants with PCLs by admission date and birth weight. We considered an infant to have catheter-related bloodstream infection if bacteremia occurred while the PCL or PIV was in place with no other identifiable infection focus. Statistical analyses were performed by using either Student’s t test or the Mann-Whitney U test where appropriate.RESULTS:There were eight infections per 1000 catheter days of PCL use and nine infections per 1000 catheter days of PIV use.CONCLUSION:PCLs do not become infected more often than PIVs.

The effect of outflow pressure upon thoracic duct lymph flow rate in fetal sheep

Edema develops when lymph does not return to the venous circulation at a rate equal to the rate of capillary filtration. Fetal sheep develop edema as well as an increased central venous pressure while undergoing atrial pacing at 320 beats per min. We hypothesized that the increased central venous pressure augmented the appearance of fetal edema by impairing the return of thoracic duct lymph to the venous circulation. To investigate this hypothesis, we studied the effect of outflow pressure upon thoracic duct lymph flow in 10 unanesthetized fetal sheep who had low resistance lymph catheters placed in the cervical thoracic duct near its junction with the left jugular vein. After the ewe and fetus recovered for 5 d, we altered the outflow pressure of the lymph catheter by adjusting its height with respect to amniotic fluid pressure and measured the resultant change in thoracic duct lymph flow rate. We found that lymph flow rate was constant over the range of outflow pressures (central venous pressures) normally encountered but decreased in a linear fashion at pressures greater than 0.68 kPa (5.1 torr). Lymph flow stopped at an outflow pressure of 2.40 kPa (18 torr). The data points are best fit by two lines obtained by a piecewise linear regression rather than a single line obtained from a linear regression. We conclude that fetal thoracic duct lymph flow is sensitive to elevations in outflow pressure. Lymph flow begins to diminish at outflow pressures corresponding to central venous pressures commonly encountered in pathologic conditions and may augment the appearance of fetal edema.

Reversal of Venous Blood Flow with Atrial Tachycardia and Hydrops in Fetal Sheep

ABSTRACT: The purpose of this project was to characterize the reversal of blood flow in the proximal inferior vena cava (IVC) seen in fetal sheep with pacing-induced atrial tachycardia and hydrops. We successfully operated on seven pregnant ewes at 118–130 d gestation to attach ECG and pacing wires, insert vascular catheters, and place Doppler flow probes around the common aortic trunk and the IVC. We also performed two-dimensional and Doppler ultrasonographic exams at baseline, after initiation of pacing, and daily thereafter. All fetuses developed hydrops. Ultrasonographic appearance of ascites and pleural effusion occurred within 4 h in four fetuses and within 48 h in all fetuses. Atrial pacing did not affect arterial pH or arterial O2 tension, but arterial CO2 tension increased by a small amount. Mean IVC pressure increased 75%, whereas mean aortic pressure remained the same. Concentrations of plasma protein and albumin and the hematocrit did not change with atrial pacing. Doppler ultrasound examination and Doppler IVC flow tracings showed that flow reversal began immediately with atrial pacing and disappeared immediately with cessation of pacing. Reversed flow was 21% of forward flow. Inspection of simultaneous recordings of ECG, Doppler aortic and IVC flows, and aortic and IVC pressure tracings revealed that the reversed blood flow occurred in diastole in conjunction with atrial contraction and, therefore, could not be due to tricuspid insufficiency. Our findings of increased venous pressure and reversed venous blood flow suggest that ventricular function is impaired and further suggest that oxygen supply to the ventricles may not be sufficient for the increased demand.

A high-value, low-cost bubble continuous positive airway pressure system for low-resource settings: technical assessment and initial case reports.

Acute respiratory infections are the leading cause of global child mortality. In the developing world, nasal oxygen therapy is often the only treatment option for babies who are suffering from respiratory distress. Without the added pressure of bubble Continuous Positive Airway Pressure (bCPAP) which helps maintain alveoli open, babies struggle to breathe and can suffer serious complications, and frequently death. A stand-alone bCPAP device can cost

An interdisciplinary bronchopulmonary dysplasia program is associated with improved neurodevelopmental outcomes and fewer rehospitalizations

6,000, too expensive for most developing world hospitals. Here, we describe the design and technical evaluation of a new, rugged bCPAP system that can be made in small volume for a cost-of-goods of approximately

Tracheostomy placement in infants with bronchopulmonary dysplasia: safety and outcomes.

350. Moreover, because of its simple design—consumer-grade pumps, medical tubing, and regulators—it requires only the simple replacement of a <

Transcatheter Elimination of Left-to-Right Shunts in Infants with Bronchopulmonary Dysplasia Is Feasible and Safe

1 diaphragm approximately every 2 years for maintenance. The low-cost bCPAP device delivers pressure and flow equivalent to those of a reference bCPAP system used in the developed world. We describe the initial clinical cases of a child with bronchiolitis and a neonate with respiratory distress who were treated successfully with the new bCPAP device.

Reduction in Plasma Protein Does Not Affect Body Water Content in Fetal Sheep

Objective:Bronchopulmonary dysplasia (BPD) is a pulmonary disease associated with poor neurodevelopmental and medical outcomes. Patients with BPD are medically fragile, at high risk for complications and require interdisciplinary care. We tested the hypothesis that a chronic care approach for BPD would improve neurodevelopmental outcomes relative to the National Institute of Child and Human Development Neonatal Research Network (NICHD NRN) and reduce medical complications.Study Design:Infants were followed as inpatients and outpatients. Bayley developmental exams were carried out at 18–24 months of age and compared with the NICHD NRN report. Finally, rates of readmission (a proxy for medical complications) were compared before and after implementation of the Comprehensive Center for BPD (CCBPD).Result:Developmental scores obtained in 2007 and 2008 show that 12 and 10% of patients with moderate BPD (n=61) had Bayley Scores <70 for mental and motor indices respectively, whereas corresponding national rates were 35 and 26%. For patients with severe BPD (n=46), 15 and 11% of patients within the CCBPD vs 50 and 42% of national patients scored <70 for mental and motor indices, respectively. Finally, readmission rates dropped from 29% in the year before the implementation of the CCPD (n=269) to 5% thereafter (n=866, P<0.0001).Conclusion:The encouraging neurodevelopmental outcomes and readmission rates associated with a chronic care approach to BPD suggest these infants may be best served by a comprehensive interdisciplinary approach to care that focuses on neurodevelopment throughout the hospital stay.

Thoracic Duct Lymph Flow in Fetal Sheep with Increased Venous Pressure from Electrically Induced Tachycardia

Optimizing the timing and safety for the placement of a tracheostomy in infants with bronchopulmonary dysplasia (BPD) has not been determined. The purpose of the present study was to describe the data from a single institution about the efficacy and safety of tracheostomy placement in infants with BPD needing long‐term respiratory support. We established a service line for the comprehensive care of infants with BPD and we collected retrospective clinical data from this service line. We identified patients that had a trachostomy placed using the local Vermont‐Oxford database, and obtained clinical data from chart reviews. We identified infants who had a tracheostomy placed for the indication of severe BPD only. Safety and respiratory efficacy was assessed by overall survival to discharge and the change in respiratory supportive care from just before placement to 1‐month post‐placement. Twenty‐two patients (750 ± 236 g, 25.4 ± 2.1 weeks gestation) had a tracheostomy placed on day of life 177 ± 74 which coincided with a post‐conceptual age of 51 ± 10 weeks. At placement these infants were on high settings to support their lung disease. The mean airway pressure (MAP) was 14.3 ± 3.3 cmH2O, the peak inspiratory pressure was 43.7 ± 8.0 cmH2O, and the FiO2 was 0.51 ± 0.13. The mean respiratory severity score (MAP × FiO2) 1 month after tracheostomy was significantly (P = 0.03) lower than prior to tracheostomy. Survival to hospital discharge was 77%. All patients with tracheostomies that survived were discharged home on mist collar supplemental oxygen. In conclusion, the high survival rate in these patients with severe BPD and the decreased respiratory support after placement of a tracheostomy suggests that high ventilatory pressures should not be a deterrent for placement of a tracheostomy. Future research should be aimed at determining optimal patient selection and timing for tracheostomy placement in infants with severe BPD. Pediatr Pulmonol. 2013; 48:245–249.

Biochemical Manifestations of Oxygen Toxicity in the Newborn Lamb

OBJECTIVE To test the hypothesis that transcatheter elimination of left-to-right (L-R) cardiac shunts in former premature infants with bronchopulmonary dysplasia (BPD) is feasible, safe, and is associated with an improvement in respiratory status. DESIGN Retrospective case review. PATIENTS Twelve patients with BPD who underwent an attempt at transcatheter closure of an L-R shunt lesion within the first year of life at a single center. Median weight was 5.4 kg and median age was 6 months. Fifteen L-R shunt lesions included patent ductus arteriosus (n = 1), atrial septal defect (ASD) (n = 9), and aortopulmonary collaterals (n = 5). OUTCOME MEASURES Echocardiographic and clinical markers were collected before and after intervention as well as procedural variables including successful elimination of the shunt and procedural complications. RESULTS The L-R shunts were successfully occluded in 11/12 (91.6%) patients without any significant procedural adverse event. The ASD closure group demonstrated a decrease in right heart size after the procedure. All patients required respiratory support prior to, and 1 month after, the procedure while only 5/10 (50%) required respiratory support at 12 months of age (P = .0129). There was no change in the median weight percentile over time. CONCLUSION Transcatheter occlusion of L-R shunts can be performed safely and effectively in children with BPD. Further studies may clarify the role of such therapy in improvement in respiratory physiology over time.