Caustic Ingestion

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Last updated: May 9, 2026Bookmark

Caustic ingestion causes chemical injury to the upper gastrointestinal tract. It most commonly affects the oesophagus (alkali) and stomach (acid).

80% occur in children. It has a high morbidity and mortality.

The severity of corrosive burns to the oesophagus depends on:

  1. Nature of corrosive substance (acid vs alkali)
  2. Quantity and concentration of the substance
  3. Duration of contact with the esophageal wall

Caustic Substances

SubstancepHExamplesPathogenesis
Alkaline Substances> 11.5Laundry detergent, lye, hair straightener, disk battery, and drying agentsCauses liquefactive necrosis: deeper penetration and more severe. There is also saponification of fat, dehydration and thrombosis of blood vessels. It is more likely to heal with fibrosis.
Acidic Substances< 2Battery fluid, toilet cleaner, sulfuric acid, swimming pool cleanersCauses coagulative necrosis: the coagulum limits penetration
Bleach~ 11Mild irritation, no significant morbidity

Esophageal burns

DegreeExtentClinical Features
First DegreeSuperficial mucosal injuryMild hyperemia and edema
Second DegreeTransmucosal injury (mucosa, submucosa, possible muscular)White exudate, erythema
Third DegreeTransmural injury (Full-thickness)Black coagulum, extension beyond the esophagus

Endoscopic grading (Zarger)

GradeDescription
Grade 0Normal
Grade 1Edema and hyperemia of the mucosa
Grade 2ASuperficial Ulceration
Grade 2BDeep ulceration
Grade 3AFocal necrosis
Grade 3BExtensive necrosis
Grade 4Perforation
  • Causes
    • Accidental ingestion
      • Children
      • Usually smaller amounts of substance
    • Intentional ingestion
      • Adults
      • Usually in larger amounts and more severe
  • Pathophysiology
    • Alkali → liquefactive necrosis and saponification of fats → deep tissue penetration → severe oesophageal damage
    • Acid → coagulative necrosis → eschar formation limits spread, but has more gastric injury
    • Three stages of esophageal burns
      • Acute necrosis
      • Granulations: the slough separates leaving a granulating ulcer
      • Stricture formation: fibrosis begins after 2 weeks and continues for 2 months or longer
  • Signs and symptoms
    • Drooling
    • Mouth pain
    • Stridor due to edema of the epiglottis
    • Dysphagia
    • Odynophagia
    • Refusal to feed in children
    • Chest and abdominal pain
  • Investigations
    • Complete blood count for infection or bleeding
    • Arterial blood gas analysis for severity
    • Chest X-ray or Abdominal X-ray for perforation
      • Pneumomediastinum or pneumoperitoneum
    • Endoscopy within 24 – 48 hours to grade injury severity (Zarger) and guide treatment
      • Perform too early (<12 hours) and the severity of damage may be missed
      • Performed too late (> 48 hours) and the procedure could perforate the oesophagus
    • Barium swallow to evaluate for stricture formation or to confirm perforation
      • This should be the first diagnostic tool instead of esophagoscopy if the patient arrives > 48 hours
  • Treatment
    • Airway protection
      • Early intubation may be needed since oedema may quickly compromise the airway
      • Tracheostomy if there is persistent stridor
    • Continuous monitoring
    • Give oxygen as needed
    • Give intravenous fluids as needed
    • DO NOT:
      • Lavage or induce vomiting as this will give the substance a “second pass” through the oesophagus, causing more damage
      • Attempt to neutralize the acid or base
      • Attempt blind nasogastric tube insertion
    • Analgesia
    • Intravenous corticosteroids to prevent stricture formation
      • Corticosteroids are contrandicated in third-degree injuries since they may mask infection and worsen healing
    • Proton pump inhibitors (PPIs)
    • Nil per os for 7- 10 days
    • Serial barium swallows every 2 weeks until healing is complete
    • Nasogastric tube or silastic stent for circumferential injuries with minimal necrosis
    • Surgery
      • Esophagectomy or gastrectomy with exploratory laparotomy to remove necrotic tissue for grade 3 injuries
    • For strictures:
      • Esophagoscopy and prograde dilatations, if permeable
      • Gastrostomy and retrograde dilatation, if impermeable
      • Esophageal reconstruction or by-pass, if dilatations are impossible
  • Complications
    • Stricture formation
      • Especially with circumferential injury
    • Pneumonia
    • Tracheoesophageal fistula
    • Laryngeal edema
    • Perforation
    • Hemorrhage and Shock
    • Mediastinitis
    • Peritonitis
    • Esophageal carcinoma
      • Caustic ingestion increases the risk by 1000x
    • Death
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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