• Understand the main toxin in Red Back spider venom.
• Detail the typical presentation of Red back spider envenomation.
• Understand the indications for the administration of Red Back spider antivenom.
• Consider under what circumstances Red Back spider antivenom could be administered without a positive identification.
• Consider under which circumstances multiple doses of Red Back spider antivenom may be required and how it should be administered.

A 50 year old man with a background history of mild asthma and hypercholesterolaemia, presents to hospital 12 hours after a spider bite. He states he was sitting in the back yard at a BBQ on an old wooden chair and felt a pin prick sensation to his left posterior thigh. When he looked down he saw a black spider with a red mark on its back. He developed an aching pain at the bite site which gradually got worse over the next 2 hours and attended another emergency department at 2 a.m. (4 hours post-bite) as the pain was keeping him awake. The Doctor gave him some paracetamol and codeine and sent him home.

On arrival in your hospital 6 hours later he complains of ongoing pain in the whole of his left leg, perineum and right thigh. He is diaphoretic to both legs. There is a small erythaematous area in the mid-part of the posterior left thigh with surrounding piloerection and tenderness. His pulse is 95/min and BP 150/95.

1. What are the clinical features of red back spider envenomation?
2. What toxin is thought to be responsible for the envenomation syndrome and how does it exert its effects?
   The patient is administered 1 ampoule of red back spider antivenom in the ED by the intramuscular route. Two hours later there has been no relief in his symptoms and he is given a second ampoule by IMI. This, however, fails to produce any relief in his symptoms.
3. What do you next?
4. What is red back spider antivenom (RBSAV)? How is it produced?
5. What are the risks associated with RBSAV administration? How should it be administered?
6. Are there any other treatments that you could consider in the treatment of latrodectism? How efficacious are these treatments?

A 24 year old female presents the Emergency Department following a spider bite. She states she was putting a new shirt on and felt a stinging sensation to her right shoulder. When she removed the shirt she found a brown spider inside it. She put it in a jar and brought it with her. She has attended the ED because of increasing pain in her right shoulder, scapula region, radiating into her right arm and anterior chest.

On examination, there is a 5 cm red mark overlying her right scapula with associated sweating at the site. Her physical exam is otherwise unremarkable. Examination of her upper limbs is normal despite the complaint of marked pain in her right arm. Pulse is 85/min, BP 145/96 and T 37.2 0C

A 12-lead ECG is performed and shows normal sinus rhythm.

The spider she brought in with her is pictured above.

1. What type of spider is the likely culprit in this case?
2. How is this spider related to the genus Latrodectus
3. How would you manage this case?
4. What is the role of RBS antivenom?
5. Can RBSAV be used for the treatment of any other spider envenomations in Australia?
6. Can RBSAV be used for the treatment of any other spider envenomations overseas?

• Understand the epidemiology of funnel-web spider bites and envenoming.
• Describe the local and systemic effects of funnel-web spider envenoming.
• Understand the management of funnel-web spider envenoming.
• Understand the indications for the use of antivenom.
• Discuss an approach to the management of big black spiders.

A 3 year old boy claims to be bitten by the spider in the garden. He initially complained of pain in his finger, and then in the car he vomited and became drowsy. On arrival to the emergency department he is unwell, cyanotic and confused, with obvious excess lacrimation and salivation. On examination: HR 160/min, systolic BP 160 mmHg; he has widespread crepitations on chest auscultation.

1. Outline the initial management of this patient.
2. What investigations are important and why?
   He has a partial response to 2 ampoules of antivenom and is now alert, not cyanosed with normal oxygen saturations; but ongoing diaphoresis and lacrimation.
3. What is the appropriate treatment?
4. Is further antivenom indicated
5. Should the patient receive premedication and what sort of premedication is appropriate?

A 57 year old male presents to hospital 30 minutes after being bitten by a large black spider on his toe. He had to kick the spider off and he was unable to collect it at the time. He has two bleeding fang marks on his toe and severe pain. He has no systemic signs and a pressure bandage with immobilization has been applied.

1. What are the likely spiders that have bitten this man?
2. The patient is in a small town about an hour by road to the closest base hospital. Outline the issues in this patient’s management.
3. Once the pressure bandage is removed how long should the patient be observed for?

A 67 year old female presents following a bite by a large black spider while picking up some leaves. She had immediate severe pain at the bite site and her son applied a tight bandage from the fingers up to the elbow. She had a past history of type II diabetes, hypercholesterolaemia and had been a smoker.

On arrival to hospital 30 minutes after the bite she is unwell with drooling, excessive generalised sweating and lacrimation, shaking, paraesthesia in the feet, hand and lips and vomiting. She has a HR 114, BP 146/100 mmHg, RR 24 and O2 Sat. 93% (on 50% oxygen). There are two puncture marks on her finger. She has a normal respiratory examination. Her ECG shows sinus tachycardia, rate of 115 bpm and there is > 2 mm ST elevation in leads V3 to V6 (see ECG below).

1. What is the initial management of this patient?
2. Discuss the specific management of the ECG changes.
   She continues to deteriorate after 4 ampoules of Funnel-web spider antivenom over the next hour requiring a non-rebreather mask and then CPAP. ABG 90 minutes after the bite is pH 7.29, PCO2 44, PO2 63 and HCO­3- 20. HR is 125/min and BP 83/45 mmHg with ongoing hypersalivation, lacrimation and fasciculations.
3. Outline the appropriate ongoing management of this patient.

• Differentiate the major types of definite spider bites in Australia.
• Understand the epidemiology of spider bite and which particular activities are associated with bites from specific spiders.
• Describe the local effects of spider envenoming.
• Understand the spectrum of White-tail spider bite and its relation to necrotic ulcers.
• Discuss an approach to the management of spider bites when the spider has not been identified.

A 12 year old girl presents following a spider-bite. She is healthy with no past medical history or known allergies. Soon after putting on her pants this morning she felt a sting on her right thigh. She immediately crushed a brown spider that had a body of about 1cm in size. The pants had been on the washing line overnight. The initial sting lasted on 5 minutes. On examination she has a raised red area about 2 cm in diameter. She is otherwise well.

1. What is the appropriate treatment for this girl and how long should she be observed in hospital?
2. What is the likely identification of the spider?
3. The girl has a history of systemic allergic reactions to bee stings. How would this change your management?
4. What is the role of prophylactic antibiotics in this patient?

A 45 year old female presents to the emergency department with an ulcer on her right lower leg. She is requesting treatment for her white-tail spider bite. Three weeks previously she had been working in the garden and developed a red lump on her lower leg. This gradually enlarged and became very painful. Over the last 2 weeks it has formed into an ulcer and has been discharging fluid. She has been treated with a 10 day course of antibiotics by her GP, but the ulcer has not improved.

1. Is this a white-tail spider bite and if not what other aetiologies should be considered?
2. Outline the appropriate investigation?
3. What treatment should the patient get?