Tetanus

Question 1

A 36-year-old Turkish builder is admitted to the emergency department with difficulty breathing, spasms and neck stiffness. You are asked to review him urgently due to concerns regarding his airway.

What are the potential causes of this patient’s symptoms?

Answer 1

Infective

• Meningitis/encephalitis.
• Oral or dental infection/abscess. * Generalised sepsis.
• Tetanus.

Non-infective

• Electrolyte disturbances e.g. hypocalcaemia.
• Epileptic seizure.
• Drug reactions/withdrawal.
• Strychnine poisoning (pesticide).
• Psychological cause.

Question 2

How is tetanus diagnosed?

Answer 2

Tetanus is caused by toxins released by Clostridium tetani, but it is primarily a clinical (rather than microbiological) diagnosis based on the patient’s history and symptoms.

Question 3

Tetanus diagnosis - history & exam?

Answer 3

History:

• Known or observed injury or trauma with an open wound.
• Sudden onset of symptoms.
• Lack of up-to-date tetanus vaccination.
• Work or home environment associated with metal, soil or manure.

Examination:

• Muscle rigidity and spasms, including neck stiffness, masseter spasm and truncal rigidity.
• Autonomic dysfunction and severe haemodynamic instability.
• Respiratory failure.

Question 4

What are the treatment options for patients with suspected tetanus?

Answer 4

• Treatment is largely supportive. Patients should be managed in the intensive care unit in a darkened, quiet room and observed closely.
• Ensure appropriate airway management with early intubation and lung protective ventilation if there are any concerns.
• Ensure close monitoring and treatment of haemodynamic instability with vasopressors and inotropes if required.
• Antimicrobial therapy should be commenced as soon as possible (intravenous metronidazole is the first line) and the patient should be discussed with a microbiology consultant.
• Tetanus human IVIg should be given to neutralise the unbound toxin.
• Consider wound debridement if there is an obvious source of infection. However, maintenance of cardiovascular and respiratory stability is the
  priority.
• Benzodiazepines and sedative agents can be used for spasm and
  rigidity control.

Question 5

What is an autonomic storm?

Answer 5

• Tetanus is associated with rapid and significant changes in cardiovascular status.
• An autonomic storm arises due to the sudden release of adrenaline and noradrenaline into the bloodstream, causing severe hypertension and tachycardia.
• This may be followed by episodes of hypotension, bradyarrhythmias and cardiac arrest.
• The patient may also demonstrate other signs of sympathetic nervous system instability including sweating, ileus and increased secretions.

Question 6

When you assess the patient, the oxygen saturations are 91% on 15L oxygen, the GCS is 10 and there is a marked stridor. What is your management?
Medical & anaesthetic emergency - MDT management, senior help etc.

Answer 6

• Declare an airway emergency and call for urgent senior help given the likely risk of a difficult airway/intubation and the obvious need for the patient to go to intensive care. Whilst awaiting specialist help, maintain the patient’s airway using a C circuit with airway adjuncts if necessary.
• Ask the anaesthetic assistant to prepare emergency equipment and drugs for intubation and ventilation and formulate a plan, including the plan for airway management in the event of failed oxygenation or intubation.
• The equipment should include an intubation checklist, suction switched on and readily accessible, a videolaryngoscope, the difficult airway trolley, an appropriately sized endotracheal tube (with one size smaller immediately available) and the resuscitation trolley.
• Apply AAGBI standard monitoring and invasive blood pressure monitoring if possible, but insertion of an arterial cannula should not delay further management.

Question 7

Management continued

Answer 7

• Given the risk of haemodynamic instability on induction, draw up vasopressor and vagolytic agents prior to induction. Perform a RSI, maintaining a stable cardiovascular state using appropriate doses of the induction agent, opioid and muscle relaxant.
• The airway should be secured with an appropriately sized endotracheal tube and lung protective ventilation initiated. The patient should be managed in the intensive care unit.
• Ongoing sedation with benzodiazepines may improve hypertonia. If not, muscle relaxant infusions may be required, with monitoring of creatine kinase levels and further treatment.