Maternal Transport, What Do We Know: A Narrative Review

Figures & data

Figure 1 Literature Review.

Table 1 Neonatal Benefits of Maternal Transport

Study	State/Country	Year(s)	Conclusions
Harris, T^Citation19	Arizona	1974–1976	Neonatal mortality risk was lower for maternal transport than for neonatal transport in almost all groups compared, but it was statistically significant in Colorado neonatal mortality risk groups F, G, and H (the highest risk groups). Maternal transport was associated with only 22.6% mortality compared to 41.0% for neonatal transports in the same groups (p<0.05).
Chien^Citation17	Canada	1996–1997	Outborn infants were at statistically higher risks of death (9% vs 16%), grade III or IV IVH (7% vs 17%), PDA (19% vs 26%), RDS (48% vs 79%), and nosocomial infection (15% vs 26%).
Harris, B^Citation18	Alabama	1975–1977	Compared in utero referrals to neonatal referrals to a Level III NICU. Found statistically lower rates of neonatal mortality (p<0.0001) and statistically lower rates of positive pressure ventilation (CPAP p<0.0005, IPPV p<0.0001). In addition, length of hospital stay was found to be shorter in the in utero referrals (13.2 days vs 20.4 days, p<0.0001).
Menard^Citation22	South Carolina	1993–1995	Compared neonatal survival rates of VLBW infants by hospital perinatal level of care. 79% of VLBW deliveries occurred at Level III centers, but neonates born at level I and level II centers had an adjusted relative risk of mortality of 1.67 (CI 1.45–1.91).
Levy^Citation21	Louisiana	1978–1979	Compared mortality rates and NICU length of stay in infants transported before and after delivery. Found slightly higher survival rate (90% vs 87%) and a shorter LOS (11.8 vs 21.4 days). However, neither was statistically significant.
Modanlou^Citation23	California	1978–1979	Neonates transported prior to delivery had lower incidence of RDS and shorter hospitalizations.
Bellini^Citation15	Southern Italy	1998–2014	Analyzed the effect of a regional transport service on the number of inborn VLBW infants and overall mortality rate in the region. During the study period there were statistically significant increases in inborn VLBW infants (p=0.002) and in overall infant mortality rates (p=0.001).
Chen^Citation16	Taiwan	2011–2016	Compared neonatal mortality rates between those born at a tertiary care center and those born elsewhere and transferred to a tertiary care center. Inborn infants had a mortality rate of 0.39% compared to 2.05% for outborn infants which was statistically significant.
Sasaki^Citation24	Japan	2003–2011	Compared inborn vs outborn extremely preterm infants. Found increased risk of severe IVH (aOR 1.49, CI 1.11–2.00), NEC (aOR 1.49, CI 1.11–2.00), and focal intestinal perforation (aOR 1.58, CI 1.09–2.30). Follow up at 3 years of life also found a higher risk of cognitive impairment (aOR 1.49, CI 1.01–2.20).
Kollee^Citation20	The Netherlands	1983	Found the odds ratio for neonatal mortality to be significantly lower in infants born after maternal transport to a tertiary care center when compared to infants delivered at local hospitals. (OR 0.4, CI 0.18–0.83) Also found significantly lower rates of RDS (OR 0.36, CI 0.20–0.65)
Sachs^Citation26	Georgia, USA	1974–1978	The relative risk of neonatal mortality was higher for a neonate born at a primary center and transported to an NICU than those born at a tertiary center and admitted directly to an NICU. (RR 1.6, CI 1.5–1.8)
Altimier^Citation25	Ohio	1999–2000	~60% of VLBW infants born at sites without a NICU required transport to a level III center. Neonatal transport was associated with a 2.6 times higher risk of death or major morbidity. (aOR 2.64, CI 1.7–4.17)

Table 2 Deliveries Enroute by Mode of Transport

Study	Country	Years of Study	Mode of Transport	Number of Patients Transported	Number Delivered Enroute
Flanagan^Citation41	Australia	1/2010-12/2011	Ground	5722	356
McLelland^Citation40	Australia	1/2009-12/2009	Ground	1517	134
Low^Citation43	U.S.	1988	Air	357	0
Elliott^Citation44	U.S.	1/1989 – 9/1990	Air	1080	0
Akl^Citation45	Australia	9/2007-12/2009	Air	500	0
Ohara^Citation46	Japan	8/2005 – 7/2006	Air	26	0
Pulkkinen^Citation47	Finland	1939–8/2013	Air	No data	2
Jony^Citation48	Canada	1/2003 – 12/2004	Air	121	0
O’Brien^Citation49	U.S.	7/2000 – 6/2002	Air	80	0

Box 1 Maternal Levels of Care (Adapted from⁵)

Accredited birthing center Able to provide care to low-risk women with uncomplicated singleton term vertex pregnancies expected to have an uncomplicated birth

Level I (Basic Care) May provide care to low- to moderate risk pregnancies with the ability to detect, stabilize, and initiate management of unanticipated maternal-fetal or neonatal problems until the patient can be transferred Capable of providing Emergency cesarean section Limited obstetric ultrasound and interpretation 24-hour laboratory and block bank Implement maternal safety bundles Initiate massive transfusion with a process to obtain more blood and components when necessary Health care providers available Every birth attended by a qualified birthing professional and appropriately trained and qualified RN Physician with privileges to perform emergency cesarean at all times Primary maternal care providers Trained and qualified RNs Anesthesia providers (maybe anesthesiologist, nurse anesthetist, or anesthesiologist assistants)

Level II (Specialty Care) Level I plus the ability to care for additional high-risk conditions Capable of providing Advanced imaging (computed tomography scan, magnetic resonance imaging, non-obstetric ultrasound, and maternal echocardiogram) Does not need to be 24h access, but at least daily access Standard obstetric imaging at all times Health care providers Ob/Gyn readily available at all times MFM readily available at all times for consultation (phone and/or telemedicine is acceptable) Anesthesiologist available at all times Medicine physicians and general surgeons readily available for obstetric patients

Level III (Subspecialty Care) Level II plus the ability to care for more complex maternal and fetal conditions as well as complex obstetric complications Capable of providing In-house availability of all blood products Advanced imaging readily available at all times Specialized obstetric ultrasound (including Doppler studies) with interpretation at all times Basic interventional radiology (specifically for uterine artery embolization) Equipment and personnel onsite to ventilate and monitor women on L&D prior to transfer to ICU Ability to accept and facilitate maternal transports Health care providers Nursing with special training and experience in complex and critical illnesses and complications Ob/Gyn physically present at all times MFM readily available at all times (must be available for onsite consultation in critical situations, must be able to provide direct care within 24 hours in most situations) Anesthesiologist physically present at all times Full complement of subspecialists readily available for inpatient consultation

Level IV (Regional Perinatal Health Care Centers) Level III plus on-site medical and surgical care of the most complex maternal and fetal conditions throughout gestation Capable of providing On-site ICU care for obstetric patients with primary or co-management with MFM Health care providers MFM team with expertise in highly complex, critically ill, or unstable patients available at all times for consultation and management Continuous availability of RNs with experience in the care of women with complex medical illnesses and obstetric complications Anesthesiologist with obstetric anesthesia experience physically present at all times Neurosurgery, cardiac surgery, and transplant subspecialists readily available at all times or a process in place to transfer to a facility that does have them.

Box 2 Transport Briefing and Checklist

Transport Briefing and Checklist (Adapted from^Citation54)

Patient identifying information (Name, DOB, MRN, etc.) Receiving hospital and contact information Date and time of initial call, when transfer was accepted, and when the patient left the sending facility Gravidity, Parity, EDD, Gestational age (or date of delivery) Indication for transfer Primary and secondary diagnoses Pertinent medical and surgical history Advanced services needed on transfer (ie, ICU, cardiac, NICU, etc.) Referring physician and primary obstetrician Accepting physician Vital signs Vaginal exam Membrane status Vaginal bleeding Fetal ultrasound findings (Presentation, placentation, EFW, etc.) Pertinent labs Assessment of external fetal monitoring Medications given Blood products given Mode of transportation Monitoring during transportation Document checklist How are they being sent? Prenatal records, labs, ultrasound reports Current labs, H&P, relevant notes, EFM strips, etc. Transfer consent

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