Construction of Femoral Vessel Nomograms for Planning Cardiac Interventional Procedures in Children 0-4 Years Old.

The objectives of this study were to construct femoral artery (FA) and femoral vein (FV) nomograms in children aged 0-4 years and to construct probability curves for the occurrence of arterial access complications based on the size of the FA. The FV and FA are commonly accessed during cardiac catheterizations in children with congenital heart diseases (CHD). However, nomograms for vessel dimensions based on child's age or size are not available. This knowledge may be helpful for interventional planning. A prospective study was performed on 400 children (age 0-4 years) with CHD undergoing cardiac catheterizations over a 3-year period. Ultrasound evaluation of the right and left FA and FV was performed under anesthesia prior to vascular access. Regression modeling was applied to derive nomograms based on quantile polynomial regression, which yielded good fit to the data judged by R-squared. GAMLSS transformation method was used to formulate smoothed percentiles. A separate prospective evaluation of FA to determine the size below which loss of pulse (LOP) are likely to occur was performed. Nomograms for FA and FV diameter and cross-sectional area against age and body surface area and probability curves for FA LOP were constructed. It is now possible to examine ultrasound-based normal sizes of femoral vein and artery in children 0-4 years of age. Femoral vessel nomograms and LOP probability curves may help with interventional planning. Future studies with larger sample size, including children of other ages may be useful.

Utility of the Medtronic microvascular plug™ as a transcatheter implantable and explantable pulmonary artery flow restrictor in a swine model.

BACKGROUND: A surgical pulmonary artery band (PAB) is used to control excessive pulmonary blood flow for certain congenital heart diseases. Previous attempts have been made to develop a transcatheter, implantable pulmonary flow restrictor (PFR) without great success. We modified a microvascular plug (MVP) to be used as a PFR. The objectives of this study were to demonstrate feasibility of transcatheter implantation and retrieval of the modified MVP as a PFR, and compare PA growth while using the PFR versus PAB. METHODS AND RESULTS: The PFR was implanted in eight newborn piglets in bilateral branch pulmonary arteries (PAs). Immediately post-PFR implantation, the right ventricular systolic pressure increased from a median of 20-51 mmHg. Transcatheter retrieval of PFR was 100% successful at 3, 6, and 9 weeks and 50% at 12-weeks post-implant. A left PAB was placed via thoracotomy in four other newborn piglets. Debanding was performed 6-weeks later via balloon angioplasty. On follow-up, the proximal left PA diameters in the PFR and the PAB groups were similar (median 8 vs. 7.1 mm; p = 0.11); albeit the surgical band sites required repeat balloon angioplasty secondary to recurrent stenosis. By histopathology, there was grade II vessel injury in two pigs immediately post-retrieval of PFR that healed by 12 weeks. CONCLUSIONS: Transcatheter implantation and retrieval of the MVP as a PFR is feasible. PA growth is comparable to surgical PAB, which is likely to require reinterventions. The use of the MVP as a PFR in humans has to be trialed before recommending its routine use.

Clinical evaluation of a radio-protective cream for the hands of the pediatric interventional cardiologist.

OBJECTIVES: The aim of this study was to evaluate the effectiveness of UltraBLOX™ radiation attenuating hand cream during lengthy cardiac catheterization procedures in children. BACKGROUND: The hands of interventional cardiologists receive high doses of radiation due to their proximity to the X-ray beam. Radiation attenuating gloves have about a 26% attenuation rate, but reduce dexterity and tactile sensation. The UltraBLOX™ cream is a new FDA-approved X-ray attenuating cream that can be applied to the operator's hands for radio-protection. METHODS: Two nanoDot™ dosimeters were secured side by side on the dorsum of the operator's (n = 2) left hand close to the wrist. One dosimeter and the rest of the hand were covered with 0.2 mm layer of the cream. The other dosimeter was unshielded. Procedures were performed using 110 kVp fluoroscopy at 15 pulses/sec. The measurements were categorized into four groups dependent on the duration of the procedure. The patients in all four groups were well matched for age and size. RESULTS: Procedural and cumulative hand radiation doses were higher with longer procedural duration. The overall % attenuation by the cream was 39.7% (28.6-51.5) and was unaffected by the length of the procedure (median: 40.9% at 30 min and 41.4% at 180 min; P = 0.66) or the dose of radiation. The kappa statistic for interobserver agreement for good tactile sensitivity was 0.82. CONCLUSIONS: UltraBLOX™ cream provides a new option for radio-protection for the hands of interventional cardiologists without impairing tactile sensitivity. There was no decrease in attenuation up to 180 min. © 2016 Wiley Periodicals, Inc.

Nurse-Led Rounds in the Pediatric Intensive Care Unit.

Pediatric intensive care units (PICUs) rely on interprofessional communication and collaboration to mitigate the risk for medical error. To operationalize these tenets, many PICUs use multidisciplinary bedside rounds as the foundation of their workflow. Bedside nurse participation in rounds is inconsistent, diminishing the return on team investment in patient safety. Given this dilemma, some institutions have shifted from provider-led to nurse-led rounds. Here, the authors explore the rationale, experiences, and outcomes of implementation of nurse-led rounds within 4 PICU service lines.

Effect of solute temperature in the measurement of cardiac output in children using the thermodilution technique.

OBJECTIVES: The primary aim of this study was to compare thermodilution (TD) cardiac index (TDCi) measured by injecting cold saline (C-TDCi) to saline at room temperature (R-TDCi). The secondary aim was to assess the change in body temperature with cold saline injections in children. DESIGN: This is a prospective, case control study. SETTING: Cardiac catheterization lab at Le Bonheur Children's Hospital, Memphis, Tennessee. PATIENTS: Eighty-six children ≤18 years of age that underwent cardiac catheterization between April 2013 and April 2015, excluding patients with admixing lesions, on inotropic support and with ejection fraction < 30%. INTERVENTIONS: A TD catheter in the main pulmonary artery was used to measure cardiac output (CO). Each patient received manual injections of saline at room temperature followed by cold saline to calculate the CO. OUTCOME MEASURES: CO by C-TDCi, R-TDCi, and Fick-Ci were compared using four different statistical methods. RESULTS: R-TDCi and Fick-Ci had a strong linear correlation (rho = 0.91 and 0.77, respectively; P < 0.0001) to C-TDCi. R-TDCi and Fick-Ci also had high 1:1 intra-class correlation to C-TDCi (ICC-rho= 0.82 and 0.68, respectively; P < 0.01). 96% confidence limits by equivalence testing for R-TDCi and Fick-Ci were 0.98-1.02 and 0.96-1.05 respectively (P < 0.0001), when compared to C-TDCi. Mean difference (±SD) calculated by Bland-Altman analysis showed a higher score for R-TDCi (0.012 ± 0.32 L/min/m2 ) compared to Fick-Ci (0.2 ± 0.72 L/min/m2 ), but it was not statistically different (P = 0.25). In a subgroup analysis of children ≤2 years (n = 27), the results from all 3 techniques were equivalent. There was a 0.2 ± 0.16ºC drop in BT compared to a 0.08 ± 0.19ºC drop in those >2 years (P > 0.05). CONCLUSIONS: Cardiac indexes determined by Fick, C-TDCi, and R-TDCi were equivalent in children. Saline at room temperature can be used as an alternative to cold saline to avoid potential drop in body temperature of these patients.

Optimum position of transthoracic intracardiac line following cardiac surgery.

OBJECTIVES: The transthoracic intracardiac line placed in the right atrium provides a convenient access to the central venous system following cardiac surgery. However, it is associated with risks such as migration and bleeding. We conducted a retrospective study to determine whether position of transthoracic line with respect to site of exit from the chest makes a difference in the rate of complications. METHODS: All infants receiving a transthoracic intracardiac line in the right atrium following cardiac surgery between June 2012 and December 2015 were part of the study. A 3.5-Fr double-lumen umbilical venous catheter was placed directly into the right atrium. The lines exited the thorax either above in the suprasternal notch (upper transthoracic line) or below the diaphragm across the abdominal wall (lower transthoracic line). Patients were analysed for complications such as catheter migration, bleeding upon removal, atrial thrombus, line occlusion, premature removal and failed removal. RESULTS: A total of 131 patients received a transthoracic intracardiac line during the study period. Of the total patients, 88 patients received the upper transthoracic line and 43 patients received the lower transthoracic line. The upper transthoracic line was associated with significantly lower incidence of catheter migration (1% vs 14%) and this held by multivariable logistic regression, adjusting for age and duration of the line (P = 0.003). There was no difference in the rate of other complications including bleeding. CONCLUSIONS: The upper transthoracic line is associated with significantly lower incidence of catheter migration and offers a more optimum position for central access following cardiac surgery.