Congenital Diaphragmatic Hernia

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Last updated: March 31, 2026Bookmark

A congenital diaphragmatic hernia (CDH) is a failure of the diaphragmatic tissue to fuse, resulting in a defect that allows abdominal contents to herniate into the thoracic cavity. The main issue with congenital diaphragmatic hernias is respiratory insufficiency due to hypoplasia of the ipsilateral lung and pulmonary hypertension. It commonly occurs on the left.

70% of patients with a congenital diaphragmatic hernia die within the first year of life

Types of congenital diaphragmatic hernia

TypeDescription
Posterolateral defectAlso known as a Bochdalek hernia. Accounts for 95% of hernias. The majority occur on the left
Non-posterolateral defectAnterior defect (Morgagni hernia) is the most common. Accounts for 2 – 3 %. May be discovered later in life since they are smaller defects
  • Signs and symptoms
    • Respiratory distress
    • Scaphoid abdomen
    • Shift of heart sounds to the right
    • Tachypnea
    • Bowel sounds or absent breath sounds on the affected side
    • Pulmonary hypertension
  • Investigations
    • Prenatal ultrasound
      • Polyhydramnios (75% of fetuses with CDH)
      • Absent stomach bubble or stomach bubble in the chest
      • Bowel loops in the chest
      • Mediastinal shift from the side of the hernia
      • Hydrops fetalis (edema in 2 of 4 of fetal spaces – skin, pericardium, pleural space, peritoneal cavity)
    • Chest X-ray
      • Abdominal contents in the thoracic cavity, typically in the left(cystic lucencies)
      • Mediastinal shift
      • Lung hypoplasia
      • Compressive atelectasis
    • Lung-to-head ratio: product of the length and width of the right lung at the level of the cardiac atria divided by the head circumference (all measurements in millimeters)
      • < 1.0 is commonly fatal
      • ≥ 1.4 is favourable
  • Treatment
    • NICU care
    • Nasogastric tube for decompression
    • Intubation and gentle mechanical ventilation
      • Allow a bit of hypercapnia – PaCO2 50 – 60 mmHg if pH remains > 7.25
    • Adjuncts
      • Inhaled nitric oxide
      • High-frequency oscillatory ventilation (HFOV)
      • Extracorporeal membrane oxygenation (ECMO)
    • Intravenous fluids and glucose
    • Delay surgery for 24-48 hours to allow for improvement of pulmonary hypertension
  • Factors associated with poor prognosis
Reference Intervals ›
Biochemistry
ACTHP: <80 ng/L
ALTP: 5–35 U/L
AlbuminP: 35–50 g/L
AldosteroneP: 100–500 pmol/L
Alk. phosphataseP: 30–130 U/L
α-AmylaseP: 0–180 IU/dL
α-FetoproteinS: <10 kU/L
Angiotensin IIP: 5–35 pmol/L
ADHP: 0.9–4.6 pmol/L
ASTP: 5–35 U/L
BicarbonateP: 24–30 mmol/L
BilirubinP: 3–17 μmol/L
BNPP: <50 ng/L
CRPP: <10 mg/L
CalcitoninP: <0.1 mcg/L
Calcium (ionized)P: 1.0–1.25 mmol/L
Calcium (total)P: 2.12–2.60 mmol/L
ChlorideP: 95–105 mmol/L
CholesterolP: <5.0 mmol/L
VLDLP: 0.128–0.645 mmol/L
LDLP: <2.0 mmol/L
HDLP: 0.9–1.93 mmol/L
Cortisol AMP: 450–700 nmol/L
Cortisol MidnightP: 80–280 nmol/L
CK ♂P: 25–195 U/L
CK ♀P: 25–170 U/L
CreatinineP: 70–100 μmol/L
FerritinP: 12–200 mcg/L
FolateS: 2.1 mcg/L
FSHP: 2–8 U/L ♂; >25 menopause
GGT ♂P: 11–51 U/L
GGT ♀P: 7–33 U/L
Glucose (fasting)P: 3.5–5.5 mmol/L
Growth hormoneP: <20 mu/L
HbA1C (DCCT)B: 4–6%
HbA1C (IFCC)B: 20–42 mmol/mol
Iron ♂S: 14–31 μmol/L
Iron ♀S: 11–30 μmol/L
Lactate (venous)P: 0.6–2.4 mmol/L
Lactate (arterial)P: 0.6–1.8 mmol/L
LDHP: 70–250 U/L
LHP: 3–16 U/L
MagnesiumP: 0.75–1.05 mmol/L
OsmolalityP: 278–305 mosmol/kg
PTHP: 0.8–8.5 pmol/L
PotassiumP: 3.5–5.3 mmol/L
Prolactin ♂P: <450 U/L
Prolactin ♀P: <600 U/L
PSAP: 0–4 mcg/mL
Protein (total)P: 60–80 g/L
Red cell folateB: 0.36–1.44 μmol/L
Renin (erect)P: 2.8–4.5 pmol/mL/h
Renin (recumbent)P: 1.1–2.7 pmol/mL/h
SodiumP: 135–145 mmol/L
TBGP: 7–17 mg/L
TSHP: 0.5–4.2 mU/L
T4P: 70–140 nmol/L
Free T4P: 9–22 pmol/L
TIBCS: 54–75 μmol/L
TriglyceridesP: 0.50–2.3 mmol/L
T3P: 1.2–3.0 nmol/L
Troponin TP: <0.1 mcg/L
Urate ♂P: 210–480 μmol/L
Urate ♀P: 150–390 μmol/L
UreaP: 2.5–6.7 mmol/L
Vitamin B12S: 0.13–0.68 nmol/L
Vitamin DS: 50 nmol/L
Arterial Blood Gases
pH7.35–7.45
PaCO₂4.7–6.0 kPa
PaO₂>10.6 kPa
Base excess±2 mmol/L
Urine
Cortisol (free)<280 nmol/24h
Hydroxyindole acetic acid16–73 μmol/24h
Hydroxymethylmandelic acid16–48 μmol/24h
Metanephrines0.03–0.69 μmol/mmol cr.
Osmolality350–1000 mosmol/kg
17-Oxogenic steroids ♂28–30 μmol/24h
17-Oxogenic steroids ♀21–66 μmol/24h
17-Oxosteroids ♂17–76 μmol/24h
17-Oxosteroids ♀14–59 μmol/24h
Phosphate (inorganic)15–50 mmol/24h
Potassium14–120 mmol/24h
Protein<150 mg/24h
Protein/creatinine ratio<3 mg/mmol
Sodium100–250 mmol/24h
Haematology
WCC4.0–11.0 ×10⁹/L
RBC ♂4.5–6.5 ×10¹²/L
RBC ♀3.9–5.6 ×10¹²/L
Hb ♂130–180 g/L
Hb ♀115–160 g/L
PCV ♂0.4–0.54 L/L
PCV ♀0.37–0.47 L/L
MCV76–96 fL
MCH27–32 pg
MCHC300–360 g/L
RDW11.6–14.6%
Neutrophils2.0–7.5 ×10⁹/L (40–75%)
Lymphocytes1.0–4.5 ×10⁹/L (20–45%)
Eosinophils0.04–0.44 ×10⁹/L (1–6%)
Basophils0–0.10 ×10⁹/L (0–1%)
Monocytes0.2–0.8 ×10⁹/L (2–10%)
Platelets150–400 ×10⁹/L
Reticulocytes0.8–2.0% / 25–100 ×10⁹/L
Prothrombin time10–14 s
APTT35–45 s
Paediatric
Pulse Rate (bpm)
Neonate140–160
Infant <1yr120–140
1–5 years110–130
5–12 years80–120
>12 years70–100
Respiratory Rate (tachypnoea)
0–2 months≥60/min
2–12 months≥50/min
1–5 years≥40/min
>5 years≥30/min
Blood Pressure (mmHg)
Term65/45
1 year75/50
4 years85/60
8 years95/65
10 years100/70
Weight Formulas
3–12 months(a + 9)/2 kg
1–6 years2a + 8 kg
>6 years(7a − 5)/2 kg
Haemoglobin (g/dL)
Term newborn13–20
1 month11–18
2 months10–15
1–2 years10–13
>2 years11–14
MUAC (6 months–5 years)
Obese>17.5 cm
Normal13.5–17.4 cm
At risk12.5–13.4 cm
Moderate malnutrition11.5–12.4 cm
Severe malnutrition<11.5 cm
Developmental Milestones
Social smile1.5 months
Head control4 months
Sits unsupported7 months
Crawls10 months
Stands unsupported10–12 months
Walks12–13 months
Talks18 months
CSF WBC (/mm³)
Term newborn0–25
>2 weeks0–5
Calculator ›

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