Some of the most frequent complications presented by preterm babies are:
Poor blood glucose control. Due to the immaturity of their glucose regulation systems and the fact they have less glucagon and fat deposits, they show decreased glucose levels (hypoglycaemia), which can involve neurological risk. Nevertheless, they may also have difficulty metabolising glucose and have excess levels (hyperglycaemia), which can also have undesirable effects.
Low red blood cell levels (anaemia), caused by lack of blood passing from the mother through the umbilical cord, infection, repeated blood extractions, and so on. If the anaemia is important, it can lead to tachycardia or poor oxygenation, and a blood transfusion may be necessary.
Yellow coloration of the skin (jaundice), for various reasons that lead to increased bilirubin, such as hepatic immaturity, high initial haematocrit, reabsorption of haematomas, incompatibility of blood group between mother and neonate, and so on. Sometimes this requires phototherapy and, exceptionally, other more complex treatments. Bilirubin is an antioxidant that is beneficial to the patient, but if its levels exceed certain values, it can damage the central nervous system.
Infection. One of the causes that can initiate premature labour, especially for very young foetuses, is infection of the membranes surrounding the foetus, or chorioamnionitis, and this infection can be transmitted to the foetus itself. Additionally, due to their immature defence mechanisms, as many are born before the transfer of maternal immunoglobulins through the placenta, particularly in the last trimester of pregnancy, preterm babies have a greater risk of infection such as sepsis (generalised infection), pneumonia, meningitis, and so on.
Respiratory failure. One of the most immature organs of a preterm neonate is the lungs. In order to help them, as well as other organs, mature, when a birth is anticipated before week 34 of gestation, whenever possible, corticoids are administered to the mother.
If after birth the newborn presents breathing difficulties due to the immaturity if its lungs (hyaline membrane disease), it will need respiratory support for the first few days through the administration of exogenous surfactant, a medicine that contributes to lung maturation. The immature lungs are more at risk of complications such as air leakage (pulmonary emphysema or pneumothorax), infection (pneumonia), or abnormal maturation and growth (bronchopulmonary dysplasia or chronic lung disease).
Cerebral haemorrhage or damage to the white matter (leukomalacia). This is the most frightening complication in a preterm baby. It is more frequent in very immature premature babies and those that have serious pathologies. There are haemorrhages or leukomalacias of varying severity, in different locations and with varying sizes, with different prognoses.
Patent ductus arteriosus. The ductus arteriosus, the conduit that connects the aorta with the pulmonary artery, should close spontaneously in the first few hours or days of life. If this does not happen, it can lead to cardiac or pulmonary overload (tachycardia and pulmonary oedema).
Apnoea. Respiratory pauses, varying in length, generally due to the immaturity of the preterm baby's nervous system. They are usually accompanied by decreased heart rate and/or oxygen saturation.
Severe intestinal inflammation (necrotising enterocolitis). This can be one of the most serious complications in a preterm baby. It results from not enough blood reaching a fairly extensive area of the intestine due to a lesion in the intestinal mucosa that may be quite large, or even become a perforation.
Frequent examinations during admittance:
Blood tests to assess signs of infection, anaemia, and levels of glucose, ions, bilirubin and gases in the blood, among other things.
Cultures of different biological fluids (blood, urine, cerebrospinal fluid, etc.) or secretions if infection is suspected.