What is the treatment for tetanus infection?

Treatment for Tetanus Infection

Active tetanus infection requires immediate administration of Human Tetanus Immune Globulin (TIG) 250-500 units intramuscularly to neutralize circulating toxin, combined with antibiotics (metronidazole or penicillin G for 14 days), aggressive wound debridement, benzodiazepines for muscle spasm control, and intensive supportive care with early tracheostomy for moderate-to-severe cases. 1, 2, 3

Immediate Interventions

Neutralize Circulating Toxin

• Administer TIG immediately at a dose of 250-500 units intramuscularly, as this neutralizes unbound toxin before it binds to neuronal cell membranes 1, 2, 3
• TIG cannot reverse damage already caused by toxin that has already bound to neurons, making early administration critical 2, 4
• Intrathecal TIG (250 IU) may be considered in early tetanus, as one study showed significantly better outcomes with only 2% mortality versus 21% mortality with intramuscular administration alone, and was devoid of side effects 5
• When administering TIG and tetanus toxoid concurrently, use separate syringes and separate injection sites 1

Eliminate Toxin Source

• Perform thorough wound debridement immediately, removing all necrotic tissue and debris that might harbor Clostridium tetani spores 1, 2
• Surgical debridement is necessary for wounds creating anaerobic conditions favorable for bacterial growth 1
• Administer antibiotics to stop further toxin production: either metronidazole or penicillin G for 14 days 2, 3, 4
• Penicillin G has been traditionally used, though metronidazole is increasingly preferred in modern practice 3, 6

Airway and Respiratory Management

Early Tracheostomy

• Perform early elective tracheostomy in moderate or severe tetanus to prevent aspiration and manage laryngeal stridor 3
• This is critical before laryngeal spasms develop, as they can cause sudden apnea 3
• Tracheostomy facilitates long-term ventilatory support, which may be needed for weeks 3, 6

Mechanical Ventilation

• Initiate mechanical ventilation for patients with refractory spasms that cannot be controlled with sedation alone 3
• Neuromuscular blocking agents (such as pancuronium bromide) may be required in conjunction with ventilation for severe, uncontrolled spasms 3, 6

Control Neuromuscular Symptoms

Benzodiazepines as First-Line

• Administer high-dose benzodiazepines (diazepam 0.2-1 mg/kg/hour) via nasogastric tube to reduce rigidity, spasms, and autonomic dysfunction 3
• Benzodiazepines work by enhancing GABA activity, counteracting the toxin's mechanism of blocking inhibitory neurotransmitters 3
• Combine with narcotics (morphine) for additional sedation and analgesia 3, 6
• Chlorpromazine may be added for additional sedation and muscle relaxation 6

Manage Autonomic Dysfunction (Dysautonomia)

Magnesium Sulfate Infusion

• Administer magnesium sulfate infusion for autonomic overactivity, which manifests as labile hypertension, tachycardia, increased secretions, sweating, and urinary retention 3
• Dysautonomia typically occurs in the second and third weeks of severe tetanus and is a common cause of mortality 3, 6
• Magnesium sulfate is preferred over beta-blockers, which can cause sudden cardiac arrest in this setting 3

Supportive Care Measures

Nutritional and Prophylactic Support

• Place nasogastric tube for feeding and medication administration, as dysphagia is common 3
• Administer ranitidine or other H2-blockers for stress ulcer prophylaxis 6
• Provide heparin for deep vein thrombosis prophylaxis, as patients are immobilized for prolonged periods 6
• Consider peripheral or central vein nutrition if enteral feeding is inadequate 6

Environmental Modifications

• Place patient in a semidark, quiet room to minimize triggers (touch, pain, bright light, sounds) that can precipitate severe spasms and apnea 3, 6

Active Immunization

Concurrent Tetanus Toxoid

• Administer tetanus toxoid 0.5 mL intramuscularly at a site separate from TIG, as natural infection does not confer immunity 1, 4, 6
• Complete the full primary vaccination series during recovery, as there is essentially no immunity acquired from tetanus infection 4

Critical Clinical Pearls

• Mortality remains high (5-50%) even with modern intensive care, with higher rates in elderly patients and those with severe autonomic dysfunction 1, 3
• The diagnosis is clinical, based on characteristic muscle rigidity (lockjaw/trismus), reflex spasms, and opisthotonic posture; cultures for C. tetani are of limited value and should not delay treatment 4, 6
• Treatment duration is prolonged (weeks to months) because supportive care must continue until all tissue-fixed tetanospasmin has been metabolized 4
• Frequent severe spasms can produce rhabdomyolysis, requiring monitoring of creatine kinase and renal function 3