Do all premature babies need to stay in an incubator? Can they receive the hepatitis B vaccine and BCG vaccine?

Author: Meng Jingwen, deputy chief nurse, Peking University First Hospital

Reviewer: Zou Liying, Chief Physician, Beijing Obstetrics and Gynecology Hospital, Capital Medical University

Live babies born before 37 weeks of gestation are called premature babies. In order to classify these premature births more finely, we use the following standards: gestational age less than 28 weeks is called extremely premature babies; gestational age between 28 and 32 weeks is called early premature babies; gestational age between 32 and 34 weeks is called mid-preterm babies; gestational age between 34 and 37 weeks is called late premature babies.

Figure 1 Original copyright image, no permission to reprint

Many premature babies are transferred to incubators directly after birth. Why do premature babies need to live in incubators?

1. What is the purpose of placing premature babies in incubators?

Normal full-term newborns have a body temperature between 36.5℃ and 37.5℃. Premature babies leave the mother's body too early, and their organs and temperature regulation centers are not fully developed. They are easily affected by the external environment temperature. For example, if the external temperature is too high, the premature baby's body temperature will rise; if the external temperature is too low, the premature baby's body temperature will drop.

Because premature babies have a relatively young gestational age, their subcutaneous fat reserves are very small. They have a heat-producing substance called brown fatty acids. Their reserves of heat-producing substances are small, and their body surface area is relatively large, which can easily cause hypothermia.

Therefore, premature babies with a birth weight of less than 2 kg generally need to be placed in an incubator to keep warm. In addition to keeping warm, the incubator is also conducive to observing the condition of the baby. Premature babies usually do not wear clothes in the incubator, only a small diaper. For example, neonatal convulsions are very hidden, and you can visually observe whether the newborn's limbs are shaking or whether there is difficulty breathing in the incubator.

Figure 2 Original copyright image, no permission to reprint

Premature babies weighing more than 2 kg are basically late-term premature babies with a gestational age of more than 34 weeks. They generally do not need to stay in an incubator unless there are some special reasons or complications that require treatment and observation. For example, newborns or premature babies with hyperbilirubinemia need to undergo blue light therapy and need to be placed in an incubator. Because blue light exposure requires exposed skin, they need to wear a phototherapy eye mask and a phototherapy diaper.

2. What complications are premature babies prone to?

Generally speaking, the younger the gestational age and the lighter the weight of the premature baby, the more complications he or she will have.

Some major complications, such as respiratory distress syndrome, occur due to dyspnea, which is caused by insufficient production of active substances on the alveolar surface. Respiratory support may be required, such as the use of pulmonary surfactant, non-invasive mechanical ventilation, and invasive mechanical ventilation.

Premature babies are also prone to infection. Some of the reasons are congenital factors, such as premature rupture of membranes causing intrauterine infection, and they are infected at birth; some are because their immune function is not very perfect and their resistance is very poor, so they are also prone to infection after birth. If an infection occurs, corresponding treatment must be given to the infection.

Premature infants with a relatively young gestational age need to be fed through a gastric tube in the early stages because they cannot fully suck with their mouths. Enteral nutrition is prone to feeding intolerance, such as gastric retention and abdominal distension, and symptomatic treatment is required.

Premature babies are more likely to develop jaundice, anemia, and electrolyte imbalances. It is necessary to monitor whether their vital signs are stable, including the acid-base balance of the internal environment and whether their metabolism is abnormal.

When caring for premature babies, we need to help them adapt to the environment outside the womb, avoid loud noises, reduce the stimulation of light to premature babies, and provide some postural support care and touch.

3. Can premature babies be vaccinated with hepatitis B vaccine and BCG vaccine within 24 hours of birth?

For normal full-term babies, they should be vaccinated with hepatitis B vaccine and BCG vaccine in the hospital within 24 hours after birth.

For premature infants, if the mother is positive for hepatitis B surface antigen, in order to block mother-to-child transmission in time, if the condition is not particularly critical and the vital signs are relatively stable, the hepatitis B vaccine should be administered within 24 hours after birth, and hepatitis B immunoglobulin should also be injected. According to the national immunization plan, two doses of hepatitis B vaccine should be completed 1 month and 6 months after the first hepatitis B vaccine. If the mother is negative for hepatitis B surface antigen and the premature infant does not have obvious contraindications to vaccination, it is also recommended to vaccinate the hepatitis B vaccine as soon as possible within 24 hours after birth.

There are certain requirements for BCG. Premature babies must weigh 2500 grams before they can be vaccinated. If the weight does not meet the standard, less than 2500 grams, it is necessary to wait until the weight reaches the standard before considering vaccination.