Nasal Noninvasive NAVA in the Very Low Birth Weight Infant
Condition: Inadequate; Pulmonary Ventilation, Newborn; Infant, Very Low Birth Weight
MeSH terms: Body Weight; Birth Weight
Study type: Interventional

Summary: 
      The purpose of this study is to determine if a new type of mechanical ventilation, or
      breathing machine (called neurally adjusted ventilatory assist or NAVA), will provide
      additional support to infants who were born prematurely. Investigators are looking to
      determine if in two hours infants who weighed less than 1500 grams or 3 pounds 5 ounces, will
      demonstrate a decrease in the amount of carbon dioxide (the gas that humans exhale) dissolved
      in their blood as compared to prior to starting the study. This will be accomplished by
      enrolling infants who are stable on their current type of mechanical breathing that provides
      a constant air flow into the infant. This type of mechanical support helps keep the lungs
      inflated but does not help remove carbon dioxide. This study will change the type of
      mechanical support to a type of support called neurally adjusted ventilatory assist or NAVA.
      This type of mechanical support detects when the infant is breathing in by having electrical
      sensors on a feeding tube that is placed into the stomach through the nose or mouth. These
      electrical sensors detect when the diaphragm or the muscle that helps humans breath is trying
      to take a breath in. When the NAVA ventilator senses the attempt to breath, it provides
      additional air flow to make the effort of breathing easier. The ventilator will be attached
      to a tube or cannula that is placed into the infant's nose. After two hours of being on the
      NAVA ventilator a repeat measure of carbon dioxide in the blood will be performed by taking a
      small amount of blood from the infant's heel.
    

Detailed description: 
      Baseline Data Collection:

      Demographic data: Patient gestational age at delivery, maternal betamethasone therapy, APGAR
      scores, admission weight, receipt of surfactant administered, age at extubation, time since
      extubation, current post menstrual age, and current weight.

      Baseline vitals and ventilation mode: Heart rate, blood pressure, FiO2 (fraction of inspired
      oxygen), oxygen saturations, transcutaneous partial pressure of carbon dioxide (TCO2) and
      current mode of ventilation will be recorded four times in a one minute period and the values
      average to minimize normal variation. Intervention time will be manipulated to begin no later
      than one hour after the previous feeding, as to minimize interruption of feedings to no
      greater than 30 minutes.

      Safety Safety: TCO2 monitor will be attached to the infant and the device will be calibrated
      according to protocol (reference TCO2 monitor manual). Carbon dioxide diffusion through the
      skin will be monitored continuously during the intervention (Bromley 08) to avoid periods of
      hypo or hypercarbia.

      Edi (electrical activity of the diaphragm) Catheter placement: Edi catheter size will be
      selected according to infant's weight and length. It will be inserted according to
      manufacturer's guidelines and adjustments will be made to optimize positioning (reference
      NAVA manual).

      NAVA settings:

      Infants will be maintained on previous level of PEEP (positive end expiratory pressure) or
      calculated PEEP, rounding up to whole numbers. Initial NAVA level will be determined by
      starting with an initial NAVA level of 0.5 microvolts/cm of H20. The NAVA level will then be
      adjusted either by increasing or decreasing to generate a PIP that is a minimum of 8 cm of
      H2O greater than the current PEEP. Apnea alarm will be set at 5 seconds, which will initiate
      the NAVA back up setting if no electrical activity is detected by the Edi catheter. Back up
      NAVA settings will be set with a PIP of 12 cm of H20 greater than current PEEP, respiratory
      rate of 60 breaths per minute (RR) and inspiratory time of 0.5 seconds. Fraction of inspired
      oxygen (FiO2) will be adjusted to keep infant's oxygen saturations within previously
      established clinical parameters.

      Study Intervention Procedure and Data Collection:

      At initiation of intervention, and at time 30, 60, 90, and 120 minutes, heart rate (HR),
      respiratory rate (RR), tidal volume (TV), minute ventilation, FiO2, oxygen saturations, peak
      Edi and PIP will be recorded four times in a one minute period and the values average to
      minimize normal variation. Current NAVA settings, TCO2, and blood pressure (BP) will also be
      recorded. At 60 minutes of intervention if the TCO2 level has not decreased by 5 torr from
      baseline or has risen, the current NAVA level will be increased by 50%. At 90 minutes if the
      TCO2 level has not decreased by 5 torr from baseline or has risen; the NAVA level will be
      increased by 50% from the current level. At the completion of the study (120 minutes or pCO2
      outside of established limits) the HR, RR, BP, TV, minute ventilation, FiO2, oxygen
      saturations, peak Edi and PIP will be recorded four times in a one minute period and the
      values average to minimize normal variation. A capillary blood gas will be obtained according
      to standard unit protocol with a warmed heel.
    

Intervention name(s): Nasal NIV-NAVA
Intervention type(s): Device
Intervention description(s): Infants will be placed on nasal NIV-NAVA. Patients initial NAVA level will be set to generate a peak inspiratory pressure that is 8 cm of water greater than their current peak end expiratory pressure. If the infants are on nasal NIV-NAVA at the time of study entry their NAVA level will be increased by 50% rounded up to the nearest 0.1 cm of water per microvolt.
Other intervention name(s): noninvasive; neurally adjusted ventilatory assist; nasal pharyngeal
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: NAVA; NIV-NAVA; VLBW; electrical activity of the diaphragm; neural trigger, mechanical ventilation; respiratory distress syndrome