1. This document provides a list of questions and factors to consider in the differential diagnosis of cyanosis in a newborn baby. It includes questions about the mother's medical history and pregnancy, the baby's history and symptoms, possible causes related to feeding, smoking exposure, and delivery complications. 2. A number of potential differential diagnoses are outlined for central, respiratory, cardiovascular, and other causes of cyanosis. Common causes include pneumonia, methemoglobinemia, and transient tachypnea of the newborn. 3. Suggested initial investigations are described that can help evaluate the cardiopulmonary status of the baby and identify potential causes, such as capillary refill time, vital signs,

1. 1 [ ]
Mariam Alosfoor
1. History
Question Reasoning
Demographics Mother’s age
Baby’s age Causes differ by age
Birth weight Preterms at higher risk to
develop RDSGestational age
Family Hx of inherited disorders?
Baby related Associated symptoms
Does the baby look blue? Since
when?
Causes and severity differ
by onset
Feeding formula Bottle fed 
methemoglobinemia
How often the baby is fed? Drowsiness, lethargy
Baby contact with smoke? Carbon monoxide
poisoning
Past mother
medical Hx.
Chronic HTN? Uteroplacental
insufficiency  IUGR
Maternal infection TORCH  sepsis
Gestational DM or chronic High risk of congenital
anomalies baby
Hx of drug intake? Respiratory depression
Pregnancy
related
Type of delivery Birth trauma, C-section
 RDS
Complications MAS
2. Differential diagnosis
Cyanosis Reasoning DDx
Central Abnormal HGB Carboxyhemoglobinemia Carbon monoxide
poisoning
Methemoglobinemia From nitrate ingestion
Deoxygenated
HGB
Respiratory Pneumonia
MAS
Pneumothorax
Diaphragmatic hernia
ARDS
Pulmonary atresia
Foreign body
Cardiovascular PPHN
Transposition of great
arteries
Tetralogy of Fallot
Hypoplastic Lt heart syn.
Neurologic Asphyxia, seizures,
sedatives
Hematologic Polycythemia
Sepsis
Peripheral Respiratory Transient Tachypnea of Newborn
Cardiovascular Coarctation of aorta  lower extremity cyanosis

2. 2 [TYPE THE DOCUMENT TITLE]
Mariam Alosfoor
3. Investigations Reasoning + (Normal)
Capillary refill time > 3 sec is abnormal
Blood pressure Signs of shock
Heart rate
Respiratory rate Grunting, rapid, depressed
Finger clubbing Tetralogy of Fallot
Radiofemoral pulse Coarctation of aorta
Chest movement, abdomen Asymmetric, scaphoid
CBC Polycythemia from the prolonged
hypoxemia
ABG PCO2 > 50 mmHg is elevated  resp. cause
pH < 7.35 = acidosis
Hyperoxia
test
PaO2 > 150 Respiratory cause
PaO2 < 150 Possible PPHT
CXR Egg on string
Cardiomegaly
Narrow base of heart
Highlighted vascular
marks
Transposition of great arteries
Concave and narrow base
of heart
Upward apex
Boot shaped heart
Lung is blackish, no or
decreased vascular marks
Tetralogy of Fallot
Figure of 3 signs (typical) Coarctation of aorta
Intestine loops in chest Diaphragmatic hernia