TUESDAY, Sept. 4, 2001 (HealthDayNews) -- If you're about to take your healthy premature baby home from the hospital, make sure the hospital checks your infant in its car seat. Some babies born between 35 and 37 weeks but who were otherwise OK developed breathing problems when placed in a car seat, a new study shows.
A premature infant's semi-upright position in the seat can cause breathing pauses (apnea), a low heart rate and low blood-oxygen levels, says Dr. Jennifer Merchant, the study's lead researcher and a neonatologist in Boise, Idaho. Because their lungs and respiratory systems are immature and their neck muscles are underdeveloped, a semi-upright position may cause premature babies to slump forward, cutting off their oxygen supply, she says.
"Prior research on this issue of preemies and cars seats was done with babies who had been in intensive-care nurseries and not with well babies," says Merchant. "Based on that prior research, the American Academy of Pediatrics (AAP) came out in 1991 and then again in 1996 with recommendations that all premature babies born at less than 37 weeks should be put in a car seat, and the hospital should check the child for respiratory problems prior to discharge."
Merchant says between 4 percent and 6 percent of all babies born in this country debut at 35 or 36 weeks, and she wondered about babies who were early but otherwise didn't require round-the-clock attention. "A good portion of those are actually healthy babies who are put in the regular nursery until they are discharged," she says. "Do these healthy near-term babies really need a car-seat test?" Merchant asks.
The answer is yes.
Her team looked at 50 babies who were considered full-term -- more than 37 weeks' gestation, and, on average, 39 weeks -- and another 50 born at 35 or 36 weeks but who didn't need intensive nursery care. Early arrivals had more problems breathing in the car seat, and some even had trouble fitting into the restraint, she says.
Twelve percent of preterm babies had apnea episodes "even though they were healthy, and their heart rates fell, and they developed low blood oxygen levels. The term babies did not have those problems," Merchant says. Moreover, the study found 24 percent of preemies didn't fit securely into the seat, while only 4 percent of term babies had that problem.
Merchant says the study found interesting and unexpected irregularities: "All the babies, term and pre-term, had small declines in their blood oxygen, though they were not in the dangerous level, and a small percentage had abnormal blood-oxygen levels." A child with already abnormal blood-oxygen levels could risk something more serious if placed in a car seat, Merchant says.
The study appears in the September issue of Pediatrics.
Dr. Daniel Levy, a spokesman for the AAP and a pediatrician in private practice in Owings Mills, Md., says, "The systems and mechanisms used for controlling oxygen and carbon dioxide levels are immature, and that can lead to problems, and if the child is kind of doubled over in the car seats, all their little air sacs in their lungs are being inadequately filled with air."
"The lower segments of their lungs can be partially collapsed, and while the blood flow to those segments is fine, they are unable to exchange gases. The child retains an abnormal amount of carbon dioxide and doesn't have an adequate supply of oxygen," Levy says.
What To Do
Parents need to be compulsive about preemies and car seats, Levy says.
"Pay attention to detail before you leave the hospital. Premature infants should be tested with both an apnea monitor and an oxygen sensor, before they go home," he says.
Merchant says, "Because of the study, we're recommending that babies in the first months of life avoid spending excess time in a car seat. Car seats should only be used for short distance travel, not extended travel. Parents should avoid any device that uses a semi-upright position, like infant swings or carriers, for the first few months of life."
For more on premature babies and car seats, see the AAP, which also has a shopping guide for car seats.
