The utility of point-of-care ultrasound protocol to confirm central venous catheter placement in the preterm infant.

Central vascular access is frequently required for preterm infants. Confirmation of positioning of central line is typically on chest and abdominal radiographs; POCUS is a relatively novel diagnostic method. Misdiagnosis is the main concern limiting use of this modality. The aim of this study is to validate our standard protocol accuracy in locating the central catheter position by correlating catheter position as determined by POCUS with radiographs. Premature babies < or equal to 30 weeks gestation who had peripheral central lines or surgical lines were enrolled. Confirmation of line position by radiographs was compared to images obtained through a specific US protocol technique. The operator of US exam was blinded to the radiograph findings. All images were reviewed by two radiologists who were blinded to the radiograph findings. 35 central line placements were assessed. 22 lines were inserted in the UL, and 13 were inserted in the LL with a total of 91 ultrasound scans and radiographs. The position of the line was interpreted as normal in 79/91 scans with interpreter reliability of [Formula: see text]=0.778 (p < 0.001), sensitivity of 0.83 and specificity of 0.96, and positive predictive value of 0.77 and negative predictive value of 0.97. There was no significant difference between the ultrasound interpretation and the radiograph interpretation of UL and LL.  Conclusion: The protocol of POCUS that we propose is a reliable tool for assessing the central line positions in preterm infants. What is Known: • POCUS is a reliable tool assessing the central line positions in preterm infants. What is New: • The protocol of POCUS that we propose is a reliable tool for assessing the central line positions in preterm infants.

Prone versus Supine Position for Lung Ultrasound in Neonates with Respiratory Distress.

OBJECTIVE: To study the feasibility of lung ultrasound (LUS) in prone position and to compare it with supine position in neonates with respiratory distress. STUDY DESIGN: Neonates ≥ 29 weeks of gestational age with respiratory distress requiring respiratory support within first 12 hours of life were enrolled prospectively. First LUS (fLUS) was done in the position infant was nursed (supine or prone), infant's position changed, a second LUS (sLUS) was performed immediately and a third LUS (tLUS) was done 1 to 2 hours later. Primary outcome was the comparison of LUS scores (LUSsc) between fLUS and sLUS. RESULTS: Sixty-four neonates were enrolled. Common respiratory diagnoses were transient tachypnea of newborn (TTN; 53%) and respiratory distress syndrome (RDS; 41%). LUSsc was different between fLUS and sLUS (fLUSsc 6 [interquatile range: 4, 7] vs. sLUSsc 7 [4, 10], p < 0.001), while there was no difference between the fLUS and tLUS (fLUSsc 6 [4, 7] vs. tLUSsc 5 [3, 7], p = 0.43). Subgroup analysis confirmed similar findings in neonates with TTN, while in babies with RDS, all the three LUSsc were similar. CONCLUSION: LUS is feasible in prone position in neonates. LUS scores were higher immediately after a change in position but were similar to baseline 1 hour after the change in position.

Effect of vasopressin on a porcine model of persistent pulmonary hypertension of the newborn.

BACKGROUND: Persistent pulmonary hypertension of the newborn (PPHN) is due to a failure of pulmonary vascular relaxation. Vasopressin, a systemic vasoconstrictor acting on smooth muscle AVPR1a receptors, is used in treatment of PPHN. We sought to determine acute effects of vasopressin infusion on pulmonary hemodynamics in a large animal model of hypoxic PPHN. METHODS: PPHN was induced in 6 newborn piglets by 72 h normobaric hypoxia (FiO2 = 0.10); controls were 7 age-matched 3-day-old piglets. Animals were anesthetized and ventilated with central venous and arterial lines, and after stabilization, randomized using a crossover design to normoxic or hypoxic ventilation, then 30 min infusion of 0.0012 U/kg/min vasopressin, followed by 45 min vasopressin washout period. Echocardiographic parameters and oxygen consumption were measured before and after vasopressin. Relaxation to vasopressin was tested in isolated PPHN and control pulmonary arteries by isometric myography. Expression of AVPR1a receptor mRNA was quantified in arterial and myocardial tissues. RESULTS: Vasopressin did not alleviate hypoxia-responsiveness of PPHN pulmonary circuit. There were no significant differences in pulmonary hypertension, cardiac function indices, or oxygenation indices after vasopressin infusion. Vasopressin did not dilate control or PPHN pulmonary arteries, and AVPR1 was minimally expressed. CONCLUSIONS: Vasopressin does not have a direct pulmonary vasodilator effect in PPHN, within the timeframe studied.

Integrated evaluation of hemodynamics: a novel approach for the assessment and management of preterm infants with compromised systemic circulation.

OBJECTIVE: To establish normal reference values for tissue oxygen delivery and consumption in preterm infants and demonstrate the usefulness of the integrated evaluation of hemodynamics (IEH) in preterm infants with compromised systemic circulation (CSC). METHODS: This study included 32 stable preterm infants and 6 infants (selected cases) who underwent IEH. IEH is a multimodal approach which integrates clinical parameters: data obtained from near-infrared spectroscopy (NIRS) and targeted neonatal echocardiography (TNE). RESULTS: Thirty-two hemodynamically stable preterm infants underwent 57 IEH studies. The mean (10th and 90th percentiles) were 0.23 (0.14 and 0.29) for cerebral fractional oxygen extraction (crFOE), 0.2 (0.13 and 0.24) for renal fractional oxygen extraction (rnFOE), and 0.22 (0.19 and 0.27) for mesenteric fractional oxygen extraction (msFOE). The time to full clinical recovery in all sick infants after the change of management was between 4 and 48 h. CONCLUSION: IEH was useful in targeting the management of preterm infants with CSC.

Neurodevelopmental Outcomes of Infants Born at <29 Weeks of Gestation Admitted to Canadian Neonatal Intensive Care Units Based on Location of Birth.

OBJECTIVE: To compare mortality and neurodevelopmental outcomes of outborn and inborn preterm infants born at <29 weeks of gestation admitted to Canadian neonatal intensive care units (NICUs). STUDY DESIGN: Data were obtained from the Canadian Neonatal Network and Canadian Neonatal Follow-up Network databases for infants born at <29 weeks of gestation admitted to NICUs from April 2009 to September 2011. Rates of death, severe neurodevelopmental impairment (NDI), and overall NDI were compared between outborn and inborn infants at 18-21 months of age, corrected for prematurity. RESULTS: Of 2951 eligible infants, 473 (16%) were outborn. Mean birth weight (940 ± 278 g vs 897 + 237 g), rates of treatment with antenatal steroids (53.9% vs 92.9%), birth weight small for gestational age (5.3% vs 9.4%), and maternal college education (43.7% vs 53.9%) differed between outborn and inborn infants, respectively (all P values <.01). The median Score for Neonatal Acute Physiology-II (P = .01) and Apgar score at 5 minutes (P < .01) were higher in inborn infants. Severe brain injury was more common among outborn infants (25.3% vs 14.7%, P < .01). Outborn infants had higher odds of death or severe NDI (aOR 1.7, 95% CI 1.3-2.2), death or overall NDI (aOR 1.6, 95% CI 1.2-2.2), death (aOR 2.1, 95% CI 1.5-3.0), and cerebral palsy (aOR 1.9, 95% CI 1.1-3.3). CONCLUSIONS: The composite outcomes of death or neurodevelopmental impairment were significantly higher in outborn compared with inborn infants admitted to Canadian NICUs. Adverse outcomes were mainly attributed to increased mortality and cerebral palsy in outborn neonates.

Cardiac Air Embolism in Neonates: A Hemodynamic Perspective.

Cardiac air embolism should be suspected in any neonate with acute unexplained cardiovascular collapse or worsening oxygenation. We present here five cases that presented with the above symptoms. A comprehensive evaluation including targeted neonatal echocardiography and near-infrared spectroscopy helped confirm the diagnosis and assess the hemodynamic state. Management was supportive including left lateral positioning, chest compressions, and cardiovascular medications to treat pulmonary hypertension and systemic hypotension.

The Impact of Integrated Evaluation of Hemodynamics on Management of Preterm Infants with Late-Onset Compromised Systemic Circulation.

Objectives To study the impact of integrated evaluation of hemodynamics (IEH), using targeted neonatal echocardiography (TNE), cerebral regional tissue oxygenation (crRTO), and fractional oxygen extraction (FOE), using near-infrared spectroscopy (NIRS) on the management of infants with late-onset compromised systemic circulation (LCSC), and evaluation of the hemodynamic characteristics. Study Design Retrospective cohort study comparing infants with LCSC who underwent IEH (April 2014 to May 2016) with an earlier EPOCH who did not undergo IEH (January 2012 to March 2014). The primary outcome was the time to recovery. Results Total 43 infants were included; 18 infants underwent IEH with a median (IQR) 2 (1-3) assessments per infant. The time to recovery was shorter in IEH group with a median (IQR) 28 hours (15-62) compared with non-IEH group 96 hours (30-160). Autoregulation was compromised in 50%, and systemic vascular resistance (SVR) was low in 67%. Conclusion IEH was associated with shorter time to recovery in infants with LCSC.