Ablett Classification (Tetanus Severity)
The Ablett classification of tetanus severity (Ablett 1967), which grades established disease.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- The severity PICTURE, chosen as a gestalt judgment over the whole descriptor set
- 3
- Severe autonomic instability involving the cardiovascular system
- Yes
Result: Grade 4 (very severe)
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Axis
- Grades ESTABLISHED tetanus. The prophylaxis decision tree is the prevention axis, a different question.
- Grade 1
- Mild trismus, general spasticity, no respiratory compromise, no spasms, no dysphagia.
- Grade 2
- Moderate trismus, rigidity, short spasms, mild dysphagia, ventilatory frequency above 30.
- Grade 3
- Severe trismus, generalized rigidity, prolonged spasms, apnoeic spells, pulse above 120, frequency above 40.
- Grade 4
- Grade 3 WITH severe autonomic instability. NOT a separate picture: 3 levels plus one boolean.
- Not thresholds
- The vital-sign figures illustrate each grade and are NOT monotone. Grading is gestalt; no vital signs are input.
- Scope
- Does not diagnose tetanus, decide airway management, or indicate immune globulin or any drug.
What you enter
- The severity PICTURE, chosen as a gestalt judgment over the whole descriptor set.
- Severe autonomic instability involving the cardiovascular system.
Full field descriptions
- The severity PICTURE, chosen as a gestalt judgment over the whole descriptor set. ONLY 1, 2 or 3 - grade 4 is not selected directly, because it is grade 3 plus autonomic instability [1 = Mild trismus, general spasticity, no respiratory compromise, no spasms, no dysphagia. 2 = Moderate trismus, rigidity, short spasms, mild dysphagia, moderate respiratory involvement, ventilatory frequency above 30. 3 = Severe trismus, generalized rigidity, prolonged spasms, severe dysphagia, apnoeic spells, pulse above 120, ventilatory frequency above 40.]
- Severe autonomic instability involving the cardiovascular system. This is the modifier that makes grade 3 into grade 4. It promotes ONLY grade 3; at grades 1 and 2 it is reported but does not create a grade 4.
How this is calculated
- Structure
- A DESCRIPTOR, not a score: no points, no sum, no grade 0.
Ablett JJL. Analysis and main experiences in 82 patients treated in the Leeds Tetanus Unit. In: Ellis M, ed. Symposium on Tetanus in Great Britain. Leeds General Infirmary, 1967:1-10. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.