Preterm births

Preterm babies born at 34 weeks or less are moved, in an incubator, from the delivery room to the neonatal unit. Those born at 35 weeks or later may stay with their mothers as long as they do not have any other pathology.

Once in the neonatal unit, the healthcare staff transfer the newborn from the transport incubator to an incubator or radiant warmer. This provides the correct temperature and humidity conditions so the baby can maintain its body temperature between 36.5 and 37ºC. Due primarily to the immaturity of their skin and lack of fatty tissue, preterm babies have difficulty regulating their temperature and they cool down easily. This increases their energy consumption and can aggravate many pathologies.

Heart rate. Newborns have a higher heart rate than an older child or adult, and this tends to be higher the fewer the weeks of gestation the neonate has had. During the first days of life, the heart rate of a preterm baby ranges from 120 to 150 beats per minute.

Breathing rate is also higher the fewer the weeks of gestation the neonate has had. Preterm babies usually breathe 50-60 times a minute, and this frequency increases when they have respiratory problems. Due to the immaturity of the respiratory system and central nervous system, preterm babies can present a fluctuating breathing rate, alternating periods of rapid breathing (tachypnoea) with others of slow, shallow breathing (bradypnoea). They can have respiratory pauses (apnoeas), which are usually short, and may be accompanied by slowed heart rate (bradycardia) and decreased oxygen saturation (desaturation). They tend to recover on their own or with mild tactile stimulation, but on other occasions they need stimulating or resuscitating by healthcare staff.

Oxygen saturation in the blood (SaO2) reflects the quantity of oxygen carried by the haemoglobin in the blood with the purpose of reaching the tissues. Normal values in preterm babies oscillate between 92% and 100%.

Arterial tension is the force the blood exerts on the artery walls whenever the heart beats. If the arterial tension is low, as can happen in seriously ill patients, it may be necessary to administer intravenous fluids and/or complex medication to standardise it.

Nasal or orogastric cannula (a tube that is inserted through the nose or mouth and reaches the stomach) where food is administered, since, due to their immaturity, it is very difficult for preterm babies of less than 32 or 33 weeks to feed themselves through breast or bottle feeding.

Central or peripheral venous catheters: through which parenteral nutrition is administered to the smallest and sickest, in addition to antibiotics or other medicines.

Infusion pumps for the slow administration of medicines or food.

Respiratory support devices. Some newborns with respiratory failure only need non-invasive ventilation (high flow, continuous positive airway pressure (CPAP) or biphasic positive airway pressure (BiPAP)). Nevertheless, if they do not maintain regular breathing, or their lungs do not perform gas exchange correctly, they often require invasive ventilation using more complex devices. In these situations it is necessary to intubate the patient.