physiology of the pre term baby

 

physiology of the pre term baby

 

1. Immunity is low due to:

· Low gamma globulins responsible for immunity.

· Delicate skin that is vulnerable to injuries and infection

· Lack of passive immunity which  usually develops around 38 weeks gestation

2. Blood system

· Has poor peripheral circulation with high tendency to hemorrhage because of weak vascular walls.

· Prone to hemorrhage due to lack of clotting factors(vitamin A is administered to promote clotting)

· Unable to store iron hence at risk of iron deficiency anemia.

· They have very few blood cells and may develop non pitting anemia

3. Weight

· Initially they lose up to 10% of their birth weight and start gaining and reach birth weight 2-3 weeks post delivery.

4. Temperature regulation is poordue to:

· Immature heat regulatory centre

· Limited food intake and low metabolic rate

· Inability to shiver and generate heat

· Excessive heat loss due to little or nosubcutaneous fat. The brown fat is usually in baby’s body by 36 weeks gestation.

 

5. Respiratory system

· Under developed respiratory centre leading to difficulty in initiation of respiration.

o Frequent apnoeic attacks with irregular respiration.

· Abdominal movements more than chest movements.

 

6. Renal system

· Immature kidneys are unable to concentrate urine hence they excrete chlorides and phosphates.

7. Digestive system

· Absence of swallowing and sucking reflexes lead to poor feeding

· Regurgitation after feeds due to underdeveloped cardiac sphincter

8. Nervous system

· All regulatory centres  are under developed.

 NURSING MANAGEMENT

 

ü Delivery of a preterm baby should be conducted in a warm room and subsequently nursed in a preterm incubator.

ü Temperatures of the incubator should be maintained within normal range of about36 – 37 *c

ü Perform first examination of the baby to assess maturity.

ü Fix NGtube and the baby with breast milk and substitute only where breast milk is not available.

ü Feed the baby using the oral feeding regime:

Ø Baby is given 60- 65 mls per kg of body weight in 24 hrs in 8 divided doses e.g. 2.5 kg baby will have 2.5 x60/8 =18.99 mls per feeding thus should be fed 3 hourly.

Ø If the baby tolerates, the feed can be increased

Ø If the baby can’t tolerate the oral feeds, give IV fluids e.g. 10% dextrose

Ø Introduce cup and spoon feeding gradually as the baby gains weight

Ø Aspirate the gastric content to rule out indigestion.

Ø Close observation to include:

-vital signs TPR

- Respiratory rhythm to note apnoeic attack

- Umbilical stump for signs of infection

-vomitting or retaining food

- general activity and emotional status

ü Provide care of IV line i.e. securing, cleaning and dressing.

ü Give nutritional supplements e.g. iron , folic acids, vitamin from the second week.

ü Administer broad spectrum antibiotic prophylactically for prevention of infection

ü  Take weight on alternate days to monitor the progress.

ü Discharge the baby at 2000 – 2500g

ü Give BCG vaccine on discharge or advice the mother to go for it.

ü Advice mother on family planning so that she gets another baby by choice and not by chance.

 COMPLICATIONS

1. Hypothermia neonaterum

2. Haemorrhagic disease of the newborn

3. Respiratory distress syndrome

4. Retrolental fibroplasias

5. Failure to thrive

6. Jaundice

7. Infections

8. Anaemia

9. Rickets