Use of Near-Infrared Spectroscopy to Monitor Lower Extremity Perfusion in Pediatric Patients Undergoing Cardiac Catheterization.

Acute femoral artery occlusion is common in pediatric patients following cardiac catheterization. A variety of means are utilized to assess lower extremity (LE) perfusion and arterial patency following cardiac catheterization including palpation of pulses, pulse oximetry, subjective assessment of lower extremity color and temperature, and ultrasound. We sought to evaluate the utility of Near-Infrared Spectroscopy (NIRS) to monitor LE perfusion in pediatric patients undergoing cardiac catheterization. INVOS pediatric sensors were placed on bilateral LE in all pediatric patients ≤ 40 kg undergoing cardiac catheterization. Data were recorded continuously from the start of the procedure until 4-6 h after completion of the procedure. NIRS readings were compared between the accessed versus non-accessed LE at baseline before start of case, time of vascular access, arterial sheath exchange when applicable, sheath withdrawal, and Safeguard application, deflation, and removal. 133 patients underwent 152 catheterizations with mean age 2.4 ± 2.3 years and mean weight 12.4 ± 13.2 kg. NIRS oximetry readings were significantly decreased in the LE with arterial access compared to non-accessed LE from time of sheath insertion until removal of the pressure assist device post procedure. A greater difference was noted in smaller patients. NIRS oximetry readings did not correlate with subjective assessment of lower extremity perfusion after arterial sheaths were removed. One patient had pulse loss 4 h post procedure with a decrease in oximetry readings noted at this point on review. Weight-based heparin protocol was initiated, and a gradual improvement in oximetry readings was noted over the next 5 h. Vascular ultrasound 12 h later showed no evidence of arterial thrombus. NIRS may be helpful in identifying patients who are risk for developing arterial thrombus post cardiac catheterization and for monitoring response to therapy; however, further study in these patients is warranted.

Risk Factors and Clinical Outcomes in Preterm Infants with Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension (PH) is a significant cause of morbidity in preterm infants, but no screening guidelines exist. We sought to identify risk factors and clinical outcomes associated with PH in preterm infants to develop a PH risk score. METHODS: Retrospective analysis of two separate populations of preterm infants (NICU cohort n = 230; Clinic registry n = 580). RESULTS: 8.3% of the NICU cohort had PH after 4 weeks of age, while 14.8% of the clinic registry had PH after 2 months of age. Lower birth weights and longer initial hospitalizations were associated with PH in both populations (p<0.001 for all tests). Using adjusted logistic regression, patent ductus arteriosus (PDA) requiring ligation was associated with PH in both the NICU cohort (OR: 3.19; p = 0.024) and the clinic registry (OR: 2.67; p<0.001). Risk factors (birth weight ≤780 grams, home supplemental oxygen use, and PDA ligation) identified in the clinic registry (training dataset) were validated in the NICU cohort with 0-1 factors present were associated with ≤1.5% probability of having PH, any 2 factors with a 25% probability, and all 3 factors with a 40% probability. CONCLUSIONS: Lower birth weight, PDA ligation, and respiratory support were associated with PH in both populations. A PH risk score based on clinical indicators from the training dataset predicted PH in the validation set. This risk score could help focus resources to preterm infants at higher risk for PH. Further work is needed to determine whether earlier or more aggressive management of ductal lesions could alter PH outcomes.

Impact of prenatal haemodynamic and functional abnormalities in Ebstein's anomaly on survival.

Predicting outcomes of foetuses with Ebstein's anomaly and tricuspid valve dysplasia continues to be challenging. Limited data exist on the prognostic significance of prenatal haemodynamic and functional parameters in this population. Our aim was to investigate the prognostic significance of haemodynamic and ventricular functional parameters in addition to associated morphometric parameters in patients with Ebstein's anomaly. We reviewed medical records of foetuses with Ebstein's anomaly and tricuspid valve dysplasia at All Children's Hospital Johns Hopkins Medicine and Johns Hopkins University between 2005 and 2012. The main outcome was survival past 30 days from birth; participants who died in utero or <30 days after birth were considered non-survivors. There were 13 survivors and seven non-survivors. We found that participants with abnormal right ventricular function predicted by low tricuspid regurgitation velocity (<2.3 m/second) (p=0.012) and low estimated right ventricular pressure (<24 mmHg) (p=0.029), a low (<7) cardiovascular profile score (p=0.029) and high (>0.53) cardiothoracic ratio (p=0.008) at the first foetal echocardiogram were less likely to survive. In addition, participants with a fossa ovalis/atrial septal length ratio <0.36 at the last foetal echocardiogram (p=0.051) were more likely to die, albeit of borderline statistical significance. Low tricuspid regurgitation velocity and low right ventricular estimated pressure, or a low cardiovascular profile score could be potential prognostic factors for Ebstein's anomaly and tricuspid valve dysplasia. However, future larger prospective studies are needed to confirm these initial findings.

Digoxin for the treatment of fetal congestive heart failure with sinus rhythm assessed by cardiovascular profile score.

OBJECTIVE: To evaluate the effects of digoxin on the progression of congestive heart failure (CHF), and to determine the best predictors of perinatal death in fetuses with sinus rhythm and CHF. METHODS: This was a retrospective case series of fetuses with CHF treated with transplacental digoxin, evaluated at baseline (before treatment), weekly during treatment, and prior to death or delivery, using a 10-point cardiovascular profile score (CVPS) consisting of echocardiographic markers of cardiac dysfunction: cardiomegaly, valve insufficiency, hydrops, and abnormal venous and arterial Doppler flow profiles. Composite CVPS and component markers were compared before and after digoxin treatment by nonparametric testing and best predictors of perinatal survival assessed by regression analysis and receiver operating characteristics. RESULTS: The overall mortality of the 28 subjects was 32%. First, last, and CVPS after 1 week of treatment predicted survival (odds ratio 2.34, 95% confidence interval 1.10-4.96) with a CVPS of > or=6 being the best predictor of survival (sensitivity 0.83, specificity 0.75). All fetuses that died had notching of the umbilical venous flow. CVPS increased from baseline during treatment (p = 0.003) in all subjects. CONCLUSIONS: The CVPS score is useful in assessing therapeutic effects of digoxin in the fetus with multiple etiologies for CHF. Further studies are needed to test the efficacy of digoxin in specific defects causing CHF.