Study to Investigate IVH in Micro-Preemie Transport
Pilot study to investigate Intraventricular hemorrhage (IVH) before, during, and after transport in the micro preemies – using Phillips Lumify mobile ultrasound device and International Biomedical Transportle™ device.
A neonatal transport has many unique differences from a transport of an older child, because of the very specific physiology of the neonate compared with older children.
Toxic environmental stimuli to these immature patients include the following.
- Frequent handling due to transfers from the out-born hospital bed into the transport incubator, and then into the bed in the receiving NICU (Neonatal Intensive Care Unit).
- Vibration and loud noises.
- Shocks from sudden braking of the vehicle and from potholes in the roads.
- Chance of hypothermia when moving from place to place.
If these infants are in the “at risk” category for IVH, that is under 32 weeks, under 1,500 grams and within the first 72 hours of life, then their risk of developing an IVH is thought to increase possibly up to 30% by the need for a transport.
About the Study
At the time Dr. Scott wrote this paper, she had not seen Ultrasound data in published neonatal literature regarding the incidence of IVH before and after transport of these micro-preemie patients.
This pilot study data was collected from rapid scans using a mobile ultrasound device (Phillips Lumify) on a small group of infants who required a transport during the first 72 hours of life.
Clinical patient data was assessed and recorded on evaluation sheets and completed by transport staff.
The unique physiology of the immature neonatal brain: The important facts that make the experience of a transport more likely to precipitate an Intraventricular Hemorrhage:
Cerebral circulation of the prematurely born fetus- only stable with the baby’s head held in neutral position with the body, similar to that in utero. Potential venous obstruction leading to venous congestion increases significantly with infants head turned out of midline. Auto-regulation of cerebral circulation has not been established due to the immaturity of the patient. This problem renders the infant patient vulnerable to all changes of pressure or blood flow that can be transmitted to the brain. This can easily occur during fluid and/or respiratory resuscitation or transfers into or out of vehicles where the infant patient can experience Trendelenberg position. (Head below feet.)
This study was performed and data was collected by Dr. Bass and his Transport staff at the Children’s Hospital of the Kings Daughters in Norfolk, Virginia, USA with the generous support of the Will Rogers Foundation.
- Patients group: 16 preterm infants were evaluated, but for purposes of the study data, one patient was excluded due to not meeting the criteria of weight or gestational age, and one patient expired before 7 days. This left 14 patients for inclusion in the pilot study data.
- Gestational age: 24-32 weeks.
- Weights: Ranged between 640-1,980 grams.
- 3 patients < 1,000 grams.
- 6 patients 1,000-1,499 grams.
- 5 patients 1,500- 2,000 grams.
- Age of patient at time of arrival of transport team: 1-8 hours of life. (Most between 2-4 hours).
- Respiratory distress syndrome
- Transport vehicle: All ambulance.
- Respiratory support: Invasive: Non-invasive. Nine patients, five patients.
- Head Ultrasound studies: These were accomplished using a Phillips Lumify mobile Ultrasound unit taken on transport. Rapid head ultrasound scans were performed by trained members of the transport team.
- Scan 1: Performed at the referring Hospital prior to transport.
- Scan 2: Repeat scan was performed in the NICU soon after the transport was completed.
Both scans were formally read by neuroradiology staff at the receiving hospital and reported to the NICU.
All patients, had a formal head ultrasound at seven days of life.
Results of Data Collected
Ultrasound data: 13/14 of the patients sustained no Intraventricular Hemorrhages either pre or post transport although two of these patients developed a grade one hemorrhage by seven days. One patient developed a grade two IVH at the out-born hospital initially noted on pre transport ultrasound, no further bleeding had occurred on post transport ultra sound. Unfortunately there was extension of the Intraventricular Hemorrhage to a grade four by seven days of life.
This is an IVH incidence rate of 7.15% before and including transport which is significantly below many of the published incidence rates for IVH occurrence thought to result from transport. Overall incidence of IVH by seven days was 21.42%, which again is lower than the 30% reported by Vermont Oxford for this group of patients. Severity of IVH was also noted to be improved with only one in 14 patients developing a grade four hemorrhage, and 2/14 developing a grade one hemorrhage.
Observational data noted on transport using the Transportle system: Yes, No.
- Easy to position and set up on Womba pod.
- 14 0 Stable securement of baby’s head in midline.
- 14 0 Transfer to NICU warmer mattress safely.
- 14 0 Use of neutro -thermal wrap.
- 14 0 Securement straps enabled safe transfer on pod.
- 14 0 VS stable with use of coverlet.
- 14 0 Position of baby for transport - supine midline.
- 14 0 Used Tortle eye shade and ear muff protection.
- 14 0 Respiratory devices remained secure.
- 14 0 Improved patient experience.
- 14 0 Accessories were helpful, used in all transports 14 0.
We have little if any data in the published literature regarding when in time Intraventricular Hemorrhages occur during transport of premature babies. With the advent of newer technology we now have the opportunity to better evaluate the time frame of occurrence and extension of Intraventricular Hemorrhage in these fragile patients.
In this pilot study the infants also had the benefit of some newer technology - the study was performed using Transportles with Womba pods during their transport. Manufactured by Tortle and sold by International Biomedical Inc. this positioning system not only has features which have been designed to reduce vibration and toxic sound using foam mattresses designed to dampen vibration, as well as ear muffs (25dB reduction in sound). But includes a head set to hold baby’s head stable in midline position. The unique Womba pod technology allows the infant to experience much less handling - patient transfers on a stable pod from one bed to another without being physically lifted and disrupted.
While we have no good baseline as to when in time the IVH’s have been occurring in the past, it is valuable to see that most of the infants in this pilot study using newer technology did not incur evidence of early intraventricular bleeding prior to transport or extension of bleeding during the transport. What we do not know is whether injury to the vascular bed occurred at one point in time, followed by bleeding at another point in time.
Dr. Scott hopes that this study, while small and limited may be a useful to encourage more studies involving mobile ultrasound techniques as well as evaluation of newer concepts and designs which address toxic environmental factors associated with transport.
Increase our understanding of the processes and relevant factors associated with IVH on transport and ultimately result in significantly reducing the incidence and severity of Intraventricular Hemorrhage in these very vulnerable patients.