DR AJAYI TETANUS.pptx ........,..................

Tetanus is still common in Africa and Nigeria more among the low socio economic status individuals

1. TETANUS AJAYI U. KOLAWOLE DEPARTMENT OF ANAESTHESIA AND INTENSIVE CARE UNIT BABCOCK UNIVERSITY TEACHING HOSPITAL 5TH JULY 2024

2. OUTLINES CLINICAL SCENARIO INTRODUCTION EPIDEMIOLOGY PATHOPHYSIOLOGY CLINICAL FEATURES TREATMENT REFERENCES

3. CLINICAL SCENARIO A 45-year-old man with dysphasia and pain in the back of the head was admitted to the emergency department. The patient was unable to open his mouth. During the clinical examination, he was conscious and distressed, had hyperhidrosis, and uncontrollable laughing. At the time of hospital admission, the patient’s vital signs were BP=175/90, HR=145, RR=30, BT=37, and SpO2=93 % at room temperature. He had severe back pain when bending his legs and head and oral examination of the patient was not possible due to masseter muscle rigidity .

4. CLINICAL SCENARIO He had no problem in upper limb function, and only a slight stiffness and tension was seen in the intercostal muscles. During lung auscultation, a reduction in lung sound intensity was detected. Tachycardia and abdominal wall muscle rigidity were remarkable, but there was not any sensitivity, tenderness, and organomegaly. The tibialis anterior muscle was normal while the deep muscles of the posterior leg were tight. Plantar reflexes were normal

5. INTRODUCTION Tetanus is caused by a gram positive Bacilus , Clostridium tetani It's a motile , spore forming obligate anaerobe Spore are found in soil, feces of animals and humans, on the surfaces of rusty tools like nails and needles Spores are eliminated by auto leaving at 120⁰c for 15 minutes .

6. EPIDEMIOLOGY Worldwide in 2019, tetanus was estimated to have caused 34,700 deaths, mostly in South Asia and Sub-Saharan Africa , but the disease is so rarely reported that this figure is only a rough estimate. According to the World Health Organization, in 2015 about 34,000 newborns died of neonatal tetanus, which was a 96% reduction since 1988 . This reduction was attributed to increased immunization.

7. EPIDEMIOLOGY Disease incidence is directly related to the immunization level in a population, attesting to the effectiveness of preventive efforts . According to RS Oruamabo In Nigeria, of the 5 million babies born annually, 240 000 (4.8%) die within the first 4 weeks of life . Globally , tetanus accounts for 7% of these neonatal deaths, but accounts for up to 20% in Nigeria.

8. PATHOPHYSIOLOGY OF TETANUS C . tetani spores usually enter through contaminated wounds. Manifestations of tetanus are caused by an exotoxin (tetanospasmin) produced when bacteria lyse. The toxin enters peripheral nerve endings, binds there irreversibly, then travels retrograde along the axons and synapses, and ultimately enters the central nervous system (CNS).

9. PATHOPHYSIOLOGY OF TETANUS As a result, release of inhibitory transmitters from nerve terminals is blocked, thereby causing unopposed muscle stimulation by acetylcholine and generalized tonic spasticity, usually with superimposed intermittent tonic seizures. Disinhibition of autonomic neurons and loss of control of adrenal catecholamine release cause autonomic instability and a hypersympathetic state. Once bound, the toxin cannot be neutralized.

10. PATHOPHYSIOLOGY OF TETANUS Most often, tetanus is generalized, affecting skeletal muscles throughout the body. However , tetanus is sometimes localized to muscles near an entry wound

11. SYMPTOMS AND SIGNS OF TETANUS The incubation period ranges from 2 to 50 days (average, 5 to 10 days ). Period of onset-(24-48hrs) period from trismus to the first spasm. Jaw stiffness (most frequent) Difficulty swallowing Restlessness

12. SYMPTOMS AND SIGNS OF TETANUS Irritability Stiff neck, arms, or legs Arching of the back (opisthotonos) Headache Sore throat Tonic spasms

13. SYMPTOMS AND SIGNS OF TETANUS Spasm Facial muscle spasm produces a characteristic expression with a fixed smile and elevated eyebrows ( risus sardonicus ). Rigidity or spasm of abdominal, neck, and back muscles and sometimes opisthotonos may occur. Sphincter spasm causes urinary retention or constipation.

14. SYMPTOMS AND SIGNS OF TETANUS Characteristic painful, generalized tonic spasms with profuse sweating are precipitated by minor disturbances such as a draft, noise, or movement. Mental status is usually clear, but coma may follow repeated spasms. During generalized spasms, patients are unable to speak or cry out because of chest wall rigidity or glottal spasm. Rarely , fractures result from sustained spasms.

15. SYMPTOMS AND SIGNS OF TETANUS Spasms also interfere with respiration, causing cyanosis or fatal asphyxia . Autonomic instability Temperature is only moderately elevated unless a complicating infection, such as pneumonia, is present. Respiratory and pulse rates are increased. Reflexes are often exaggerated. Protracted tetanus may manifest as a very labile and overactive sympathetic nervous system, including periods of hypertension, tachycardia, and myocardial irritability.

16. Symptoms and Signs of Tetanus Causes of death Respiratory failure is the most common cause of death. Laryngeal spasm and rigidity and spasms of the abdominal wall, diaphragm, and chest wall muscles cause asphyxiation. Hypoxemia can also induce cardiac arrest, and pharyngeal spasm leads to aspiration of oral secretions with subsequent pneumonia, contributing to a hypoxemic death. Pulmonary embolism is also possible. However , the immediate cause of death may not be apparent.

17. SYMPTOMS AND SIGNS OF TETANUS Localized tetanus In localized tetanus, there is spasticity of muscles near the entry wound but no trismus ; spasticity may persist for weeks. Cephalic tetanus is a form of localized tetanus that affects the cranial nerves. It is more common among children; in them, it may occur with chronic otitis media or may follow a head wound. Incidence is highest in Africa and India. All cranial nerves can be involved, especially the 7th. Cephalic tetanus may become generalized.

18. SYMPTOMS AND SIGNS OF TETANUS Tetanus neonatorum (neonatal tetanus) Tetanus in neonates is usually generalized and frequently fatal. It often begins in an inadequately cleansed umbilical stump in children born of inadequately immunized mothers. Onset during the first 2 weeks of life is characterized by rigidity, spasms, and poor feeding. Bilateral deafness may occur in surviving children.

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20. DIAGNOSIS OF TETANUS Clinical evaluation Tetanus should be considered when patients have sudden, unexplained muscle stiffness or spasms, particularly if they have a history of a recent wound. Tetanus can be confused with meningoencephalitis of bacterial or viral origin, but the following combination suggests tetanus: An intact sensorium Normal cerebrospinal fluid Muscle spasms

21. DIAGNOSIS OF TETANUS Trismus must be distinguished from peritonsillar or retropharyngeal abscess or another local cause. Phenothiazines can induce tetanus-like rigidity (e.g., dystonic reaction, neuroleptic malignant syndrome). C. tetani can sometimes be cultured from the wound, but culture is not sensitive; only 30% of patients with tetanus have positive cultures . Also, false-positive cultures can occur in patients without tetanus.

22. TREATMENT OF TETANUS General principles The patient should be kept in a quiet room . Prevent further toxin release by debriding the wound and giving an antibiotic. Neutralize unbound toxin outside the CNS with TIG. Immunize using tetanus toxoid, taking care to inject it into a different body site than the antitoxin. Minimize the effect of toxin already in the CNS.

23. TREATMENT OF TETANUS Wound care Because dirt and dead tissue promote C. tetani growth, prompt, thorough debridement, especially of deep puncture wounds, is essential. Antibiotics are not substitutes for adequate debridement and immunization but typically are given.

24. TREATMENT OF TETANUS Antitoxin and toxoid The benefit of human-derived antitoxin depends on how much tetanospasmin is already bound to the synaptic membranes—only free toxin is neutralized. For adults, TIG 500 units IM once appears as effective as higher doses ranging from 3000 to 6000 units and causes less discomfort. Some medical experts recommend infiltration of part of the dose locally around the wound, but its efficacy has not been proved.

25. TREATMENT OF TETANUS Tetanus infection does not confer immunity, so unless their vaccination history indicates completion of a full primary series. So, patients should receive a full primary tetanus vaccination series using an age-appropriate preparation. Antitoxin and vaccine should be injected into different body sites to avoid neutralizing the vaccine.

26. TREATMENT OF TETANUS Management of muscle spasms Medications are used to manage spasms. Benzodiazepines are the standard of care to control rigidity and spasms. They block reuptake of an endogenous inhibiting neurotransmitter, gamma- aminobutyric acid (GABA), at the GABAA receptor. Diazepam can help control seizures, counter muscle rigidity, and induce sedation. Dosage varies and requires meticulous titration and close observation.

27. TREATMENT OF TETANUS Diazepam has been used most extensively, but midazolam is water soluble and preferred for prolonged therapy. Midazolam reduces risk of lactic acidosis due to propylene glycol solvent, which is required for diazepam and lorazepam, and reduces risk of long-acting metabolites accumulating and causing coma.

28. TREATMENT OF TETANUS Benzodiazepines may not prevent reflex spasms, and effective respiration may require neuromuscular blockade with vecuronium or other paralytic medications and mechanical ventilation. Pancuronium has been used but may worsen autonomic instability. Vecuronium is free of adverse cardiovascular effects but is short-acting. Longer-acting medications ( eg , pipecuronium , rocuronium ) also work, but no randomized clinical comparative trials have been done.

29. TREATMENT OF TETANUS Intrathecal baclofen (a GABAA agonist) is effective in treating reflex spasms but has no clear advantage over benzodiazepines. Coma and respiratory depression requiring ventilatory support are potential adverse effects. Dantrolene can be given initially by infusion and thereafter for up to 60 days. Hepatotoxicity and expense limit its use.

30. TREATMENT OF TETANUS Management of autonomic dysfunction Morphine may be given every 4 to 6 hours to control autonomic dysfunction, especially cardiovascular; total daily dose is 20 to 180 mg Beta-blockade is used to control episodes of hypertension and tachycardia, but use of long-acting medications such as propranolol is not recommended.

31. TREATMENT OF TETANUS Sudden cardiac death is a feature of tetanus, and beta-blockade can increase risk; however, esmolol , a short-acting beta-blocker, has been used successfully. IV atropine has been used at high doses; blockade of the parasympathetic nervous system markedly reduces excessive sweating and secretions. Lower mortality has been reported in clonidine-treated patients than in those treated with conventional therapy .

32. TREATMENT OF TETANUS Magnesium sulfate given by IV continuous infusion at doses that maintain serum levels between 4 to 8 mEq/L has a stabilizing effect, eliminating catecholamine stimulation. Patellar tendon reflex is used to assess over dosage. Tidal volume may be impaired, so ventilatory support must be available. Serum magnesium levels and electrical cardiac activity need to be closely monitored throughout the infusion period.

33. TREATMENT OF TETANUS Other medications that may prove useful include Pyridoxine, which lowers mortality in neonates Valproic acid, which blocks GABA-aminotransferase, inhibiting GABA catabolism Angiotensin-converting enzyme inhibitors, which inhibit angiotensin II and reduce norepinephrine release from nerve endings

34. TREATMENT OF TETANUS Dexmedetomidine (a potent alpha-2 adrenergic agonist) Adenosine, which reduces presynaptic norepinephrine release and antagonizes the inotropic effect of catecholamines Corticosteroids are of unproven benefit; their use is not recommended. Antibiotics Metronidazole is the recommended antibiotic.

35. TREATMENT OF TETANUS Supportive care In moderate or severe cases, patients should be intubated. Mechanical ventilation is essential when neuromuscular blockade is required to control muscle spasms that impair respirations. IV hyperalimentation avoids the hazard of aspiration secondary to gastric tube feeding.

36. TREATMENT OF TETANUS Because constipation is usual, stools should be kept soft. A rectal tube may control distention. Bladder catheterization is required if urinary retention occurs. Chest physiotherapy, frequent turning, and forced coughing are essential to prevent pneumonia. Analgesia with opioids is often needed.

37. PROGNOSIS FOR TETANUS The case fatality rate of patients with tetanus varies widely between resource-rich and resource-poor nations. With use of modern supportive care, including mechanical ventilation, most patients recover. Untreated neonates and adults have a high mortality rate . Mortality is highest at the extremes of age and in injection drug users. The prognosis is poorer if the incubation period is short and symptoms progress rapidly or if treatment is delayed .

38. PREVENTION OF TETANUS Tetanus vaccination is required for all infants, children, adolescents, and adults.

39. SUMMARY Tetanus is caused by a toxin produced by Clostridium tetani in contaminated wounds. Tetanus toxin blocks release of inhibitory neurotransmitters, causing generalized muscle stiffness with intermittent spasms; seizures and autonomic instability may occur. Prevent further toxin release by debriding the wound and giving an antibiotic ( eg , metronidazole), and neutralize unbound toxin with human tetanus immune globulin .

40. SUMMARY Give IV benzodiazepines for muscle spasm, and use neuromuscular blockade and mechanical ventilation as needed for respiratory insufficiency due to muscle spasm. Mortality is high in untreated neonates and adults. Prevent tetanus by following routine immunization recommendations.

41. REFERENCES 1. Centers for Disease Control and Prevention: Why CDC is Working to Prevent Global Tetanus. Page last reviewed: 03/22/2022. 2. World Health Organization: Tetanus. 05/09/2018. 3. Centers for Disease Control and Prevention (CDC): Tetanus: Surveillance. Page last reviewed: 03/07/2023. 4. Faulkner A, Tiwari T: Chapter 16: Tetanus. In Manual for the Surveillance of Vaccine-Preventable Diseases, edited by SW Roush, LM Baldy, MA Kirkconnell Hall. Centers for Disease Control and Prevention, National Center for Immunization and Respiratory Diseases. Page last reviewed: February 6, 2020.

42. REFERENCES 5 . Thwarts CL, Yen LM, Cordon SM, et al: Effect of magnesium sulphate on urinary catecholamine excretion in severe tetanus. Anaesthesia 63(7):719–725, 2008. 6 . Centers for Disease Control and Prevention: Why CDC is Working to Prevent Global Tetanus. Accessed April 23, 2023.