Any person, 16 years and over, presenting with a suspected or confirmed bite from a snake or spider.
Escalate immediately as per local CERS protocol for all snake and suspected funnel-web spider bites.
This protocol is intended to be used by registered and enrolled nurses within their scope of practice and as outlined in The Use of Emergency Care Assessment and Treatment Protocols (PD2024_011). Sections marked triangle or diamond indicate the need for additional prerequisite education prior to use. Check the medication table for dose adjustments and links to relevant reference texts.
- Apply first aid.
- Complete rapid clinical assessment.
- Suspected snake bite or signs of envenomation: seek advice from the Poisons Information Centre 13 11 26 or a local clinical toxicologist.
- All suspected and confirmed snake bite patients need to be transferred to a site with a formal laboratory.
History prompts, signs and symptoms
These are not exhaustive lists. Maintain an open mind and be aware of cognitive bias.
History prompts
- Presenting complaints
- Onset of symptoms
- Events surrounding presentation
- Time of bite
- Number of bites
- Bite site location
- Physical activity since the bite
- Pain assessment – PQRST
- Prehospital treatment, including time and type of first aid applied
- Past admissions
- Medical and surgical history, including haematological disorders and history of anti-venom administration
- Use of non-prescription drug or alcohol
- Current medications, including anticoagulants
- Known allergies
- Vaccination status
Signs and symptoms
All bites by big black spiders in eastern Australia should be managed as suspected funnel-web spider bites for the first 4 hours after being bitten.
For signs of envenomation see red flags section
Snakes and funnel-web spiders:
- Local effects are not a major feature of bites by Australian snakes or funnel-webs and do not indicate severity
- Bite marks or puncture wounds
- Pain
- Swelling
- Pain at draining lymph node
Redback spiders:
- Local and systemic pain
- Occasionally symptoms in other parts of the body, e.g. chest pain, leg sweating or headache
Red flags
Recognise: identify indicators of actual or potential clinical severity and risk of deterioration.
Respond: carefully consider alternative ECAT protocol. Escalate as per clinical reasoning and local CERS protocol, and continue treatment.
Historical
- Previous antivenom administration
- Snake handler
Clinical
Envenomation – snake
Non-specific
- Nausea and/or vomiting
- Abdominal pain
- Diarrhoea
- Headache
- Diaphoresis
Cardiovascular
- Collapse
- Tachycardia
- Hypertension or hypotension
- Bleeding from the bite site, cannula site or elsewhere
Neurological
- Altered level of consciousness
- Dysphagia (difficulty swallowing)
- Pooling of oral secretions
- Respiratory muscle weakness
- Ptosis (drooping upper eyelid)
- Ophthalmoplegia (paralysis of eye muscles which may cause blurry or double vision)
- Dysarthria (slurred speech caused by neurological damage)
- Dysphonia (disordered sound production)
- Descending paralysis
- Limb weakness
Envenomation – funnel-web spider
Non-specific
- Agitation
- Headache
- Abdominal pain
- Nausea and/or vomiting
Autonomic
- Bradycardia or tachycardia
- Hypertension
- Hypersalivation
- Diaphoresis
- Piloerection (goosebumps)
- Miosis (pupil constriction) or mydriasis (dilated pupils)
Neuromuscular
- Fasciculations (brief, spontaneous contraction or twitch in a muscle), commonly tongue
- Paraesthesia
- Muscle spasms
Other severe effects
- Decreased GCS
- Multiorgan failure
- Pulmonary oedema
- Hypotension (later sign)
Remember adult at risk: patient or carer concern, frailty, multiple comorbidities or unplanned return.
Clinical assessment and specified intervention (A to G)
If the patient has any Yellow or Red Zone observations or additional criteria (as per the relevant NSW Standard Emergency Observation Chart), refer and escalate as per local CERS protocol and continue treatment.
Position
| Assessment | Intervention |
|---|---|
General appearance/first impressions | Position of comfort Keep patient immobile |
Airway
| Assessment | Intervention |
|---|---|
Patency of airway | Maintain airway patency Consider airway opening manoeuvres and positioning If airway adjuncts are required, insert them gently and consider the potential for bleeding |
Breathing
| Assessment | Intervention |
|---|---|
Respiratory rate and effort Auscultate chest (breath sounds) Oxygen saturations (SpO2) | Assist ventilation, as clinically indicated Consider oxygen if dyspnoeic, titrate oxygen to maintain SpO2 over 93% Patients at risk of hypercapnia, maintain SpO2 at 88–92% |
Circulation
| Assessment | Intervention |
|---|---|
Snake or funnel-web spider bite | Apply pressure bandage with immobilisation (PBI) Use a broad, 15 cm, elasticised bandage. The bandage is applied over the bite site and then distally to proximally, covering the whole limb. Leave bandage in situ if already placed, or reinforce if current bandage is inadequate Hourly neurovascular observations of the affected limb to ensure perfusion is maintained Include assessment of sensation, motor function and perfusion, i.e. pulses, colour, temperature, swelling and capillary refill |
Redback spider bite | A pressure bandage is not recommended, and will only make the pain worse Cold packs or heat packs may help relieve pain |
Bleeding | Look for bleeding from the bite site, cannulation site or occult sites , e.g. gastrointestinal, urinary or intracranial Consider as a sign of envenomation |
Perfusion (capillary refill, skin warmth and colour) Pulse Blood pressure Cardiac rhythm | Assess circulation Attach cardiac monitor and complete 12 lead ECG if BP/HR are within the Yellow or Red Zones, or where clinically relevant, e.g. irregular pulse, palpitations, syncope, shock, respiratory compromise, cardiac history or clinical concern |
IVC and/or pathology | Insert IV cannula, if trained and clinically indicated If unable to obtain IV access, consider intraosseous, if trained |
Signs of shock: tachycardia and CRT 3 seconds and over and/or abnormal skin perfusion and/or hypotension | If signs of shock present and/or SBP less than 90 mmHg, give 250 mL of sodium chloride 0.9% IV/intraosseous bolus Repeat every 10 minutes (up to 1000 mL) until SBP over 90 mmHg or signs of shock have resolved |
Disability
| Assessment | Intervention |
|---|---|
GCS, pupillary response and limb strength | Obtain baseline and repeat assessment as clinically indicated Consider altered conscious state as a sign of envenomation |
| Pain | Assess pain. If indicated, give early analgesia as per analgesia section then resume A to G assessment |
Exposure
| Assessment | Intervention |
|---|---|
| Temperature | Measure temperature |
| Skin inspection, including posterior surfaces | Look for bite sites, but do not remove pressure bandage Palpate lymph nodes for tenderness |
Fluids
| Assessment | Intervention |
|---|---|
| Hydration status – last ate, drank, bowels opened, passed urine or vomited | Commence fluid balance chart, as required |
| Nausea and/or vomiting | If present, consider envenomation and see nausea and/or vomiting section Antivenom takes precedence over symptom management |
Glucose
| Assessment | Intervention |
|---|---|
BGL | Measure BGL, if clinically indicated If less than 4 mmol/L, consider hypoglycaemia protocol |
Repeat and document assessment and observations to monitor responses to interventions, identify developing trends and clinical deterioration. Escalate care as required according to the local CERS protocol.
Focused assessment
- Complete a cardiovascular focused assessment.
- Complete a neurological focused assessment.
Precautions and notes
- See NSW Health Snake and Spider Bite Clinical Management Guidelines.
- Do not remove pressure bandage with immobilisation (PBI) until:
- antivenom is readily available
- a medical review has occurred
- there are no clinical signs of envenomation
- laboratory investigations have occurred and bloods have returned to normal.
- Risk of anaphylaxis with antivenom is highest in the first hour post administration.
Snake bite
- A snake bite observation chart is recommended for recording specific signs associated with snake bites or envenomation.
- Snake bite victims with significant coagulopathy: IM injections should usually be avoided, except for Boostrix or ADT booster.
- Point of care testing (PoCT) devices are inaccurate in testing for INR, aPTT and D-dimer in snake bite and should not be used.
- Patients with a suspected snake bite must be transferred to a hospital with formal laboratory facilities unless an INR can be done locally with a result available within 2 hours. However, if systemic envenomation is evident, antivenom should be given before transfer. Be prepared to manage anaphylaxis and discuss with the Poisons Information Centre 13 11 26 or local clinical toxicologist if this occurs.
Interventions and diagnostics
Specific treatment
- Treatment is focused on determining if patient is envenomed and what treatment is required. This is done in consultation with a local medical practitioner and the Poisons Information Centre 13 11 26 or local clinical toxicologist.
- Identification of the snake should only be done by experts. Snake handlers may be able to assist in the identification of snakes. However, Australian snakes have overlapping shapes, sizes and colours and non-expert identification is generally incorrect.
- Systemic envenomation: prepare for administration of antivenom.
- Venom-induced consumptive coagulopathy (VICC) – life-threatening bleed: consider early administration of fresh frozen plasma (FFP) if actively bleeding, in consultation with a medical practitioner and local clinical toxicologist.
- Funnel-web spider envenomation: prepare for administration of antivenom.
- Redback spider envenomation: provide effective analgesia.
- Antivenom administration: if patient proceeds to antivenom administration, prepare equipment to manage anaphylaxis. Consider anaphylaxis or allergic reaction protocol.
Analgesia
Select pain score:
Pain score 1–3 (mild)
Give paracetamol 1000 mg orally once only
and/or ibuprofen 400 mg orally once only
Ibuprofen should not be given for pain relating to snake bite.
Pain score 4–6 (moderate)
Give:
oxycodone (immediate release):
- 16–65 years: 5 mg orally and, if required, repeat once after 30 minutes, maximum dose 10 mg
- 65 years and over: 2.5 mg orally and, if required, repeat once after 30 minutes, maximum dose 5 mg
and/or paracetamol 1000 mg orally once only
and/or ibuprofen 400 mg orally once only
Ibuprofen should not be given for pain relating to snake bite.
Pain score 7–10 (severe)
Give one of:
Fentanyl intranasal
- 16–65 years: 50 microg intranasally and, if required, repeat once after 5 minutes, maximum dose 100 microg. Dose to be divided between nostrils
- 65 years and over: 25 microg intranasally and, if required, repeat once after 5 minutes, maximum dose 50 microg. Dose to be divided between nostrils
Note: ensure an extra 0.1 mL is drawn up for the first dose to account for the dead space in the mucosal atomiser device
Fentanyl IV
- 16–65 years: 50 microg IV and, if required, repeat once after 5 minutes, maximum dose 100 microg
- 65 years and over: 25 microg IV and, if required, repeat once after 5 minutes, maximum dose 50 microg
Morphine IV
- 16–65 years: 5 mg IV and, if required, repeat once after 5 minutes, maximum dose 10 mg
- 65 years and over: 2.5 mg IV and, if required, repeat once after 5 minutes, maximum dose 5 mg
Morphine IM
- 16–65 years: 5 mg IM and, if required, repeat once after 60 minutes, maximum dose 10 mg
- 65 years and over: 2.5 mg IM and, if required, repeat once after 60 minutes, maximum dose 5 mg
Methoxyflurane
- Using a 3 mL self-administered device, instruct the patient to inhale through the mouthpiece and take a couple of gentle breaths to get used to the fruity smell and taste; then take 6–8 deep breaths once only
and/or paracetamol 1000 mg orally once only
and/or ibuprofen 400 mg orally once only
Ibuprofen should not be given for pain relating to snake bite.
If pain does not improve with medication, escalate as per local CERS protocol.
Nausea and/or vomiting
If nausea and/or vomiting is present, give:
- metoclopramide 10 mg orally or IV/IM once only (over 20 years only)
- or ondansetron 4 mg orally or IV/IM. If symptoms persist after 60 minutes, repeat once, maximum dose 8 mg
- or prochlorperazine 5 mg orally once only or 12.5 mg IV/IM once only
Choice of antiemetic should be determined by cause of symptoms.
Tetanus
If patient has a ‘tetanus-prone’ wound, consider giving a tetanus booster vaccine.
- Diphtheria and tetanus (ADT booster) vaccine should be given as per the Australian Immunisation Handbook Guide for tetanus prophylaxis in wound management.
- If ADT booster is not available then diphtheria/tetanus/pertussis (Boostrix) vaccine can be used.
- If no documented history of a primary vaccination course (3 doses) with a tetanus toxoid-containing vaccine: refer to medical or nurse practitioner or nurse immuniser.
- If pregnant or breastfeeding: dTpa vaccine (diphtheria-tetanus-acellular pertussis) is recommended. Refer to medical or nurse practitioner or nurse immuniser.
Radiology
Not usually indicated. If there is concern for urgent radiology, escalate care as per local CERS protocol.
Pathology
Snake bite
- Point of care cannot be used – formal laboratory testing is needed
- FBC, UEC, CK
- Coags: including INR, aPTT, fibrinogen, d-Dimer
- Urinalysis: collect and check for blood which may indicate myoglobinuria or haemoglobinuria
Funnel-web spider bite
- Experiencing extreme hypertension or is hypotensive: troponin
Medications
The shaded sections in this protocol are only to be used by registered nurses who have completed the required education.
Drag the table right to view more columns or turn your phone to landscape
| Drug | Dose | Route | Frequency |
|---|---|---|---|
0.5 mL | IM | Once only | |
OR | |||
0.5 mL | IM | Where ADT booster not available Once only | |
Fentanyl H, R | 16–65 years: 65 years and over: | IV/intranasal | Pain score 7–10 Repeat once if required after 5 minutes to maximum dose |
Ibuprofen H, R | 400 mg | Oral | Pain score 1–10
Once only |
3 mL via self–administered device | Inhalation | Pain score 7–10 Once only | |
Over 20 years: | Oral/IV/IM | Once only | |
Morphine H, R | 16–65 years:
65 years and over: | Pain score 7–10 | |
| IV | Repeat once if required after 5 minutes | ||
| IM | Repeat once if required after 60 minutes | ||
4 mg Maximum dose 8 mg | Oral/IV/IM | Repeat once if required after 60 minutes | |
16–65 years:
65 years and over: | Oral | Pain score 4–6 Repeat once if required after 30 minutes to maximum dose | |
Oxygen | 2–15 L/min, device dependent | Inhalation | Continuous |
1000 mg | Oral | Pain score 1–10 Once only | |
5 mg | Oral | Once only | |
OR | |||
12.5 mg | IV/IM | Once only | |
250 mL Maximum dose 1000 mL | IV/intraosseous | Bolus Repeat every 10 minutes (up to 1000 mL) until SBP over 90 mmHg or signs of shock have resolved | |
Medications with contraindications or requiring dose adjustment are marked:
- H for patients with known hepatic impairment
- R for patients with known renal impairment.
Escalate to medical or nurse practitioner.
References
- Australian Resuscitation Council and New Zealand Resuscitation Council. ANZCOR Guideline 9.4.1 - First Aid Management of Australian Snake Bite. Australia and New Zealand: ANZCOR; 2020 [cited 23 Feb 2023]. Available from: https://survive-student-resource.austererisk.com/environmental/anzcor_9_4_1_snake_bite.html
- Australian Resuscitation Council and New Zealand Resuscitation Council. ANZCOR Guideline 9.4.2 - First Aid Management of Spider Bite. Australia and New Zealand: ANZCOR; 2020 [cited 23 Feb 2023]. Available from: https://survive-student-resource.austererisk.com/environmental/anzcor_9_4_2_spider_bite.html
- Australian Technical Advisory Group on Immunisation (ATAGI). The Australian Immunisation Handbook provides clinical advice for health professionals on the safest and most effective use of vaccines in their practice. Canberra, Australia: Australian Technical Advisory Group on Immunisation (ATAGI); 2022 [cited 16 February 2023]. Available from: https://immunisationhandbook.health.gov.au/
- Beasley R, Chien J, Douglas J, et al. Thoracic Society of Australia and New Zealand oxygen guidelines for acute oxygen use in adults: 'Swimming between the flags'. Respirology. 2015 Nov;20(8):1182-91. DOI: 10.1111/resp.12620
- Long N. Approach to Snakebite. Australia: Life in the Fast Lane; 2020 [cited 23 Feb 2023]. Available from: https://litfl.com/approach-to-snakebite/
- MIMS Australia. Clinical Resources. Australia: MIMS Australia Pty Ltd; 2022 [cited 2 Feb 2023]. Available from: https://www.mimsonline.com.au.acs.hcn.com.au/Search/Search.aspx
- NSW Emergency Care Institute. Snakebite and Spiderbite Clinical Management Guidelines 2013 - Third Edition (Check updated version). Australia: Agency for Clinical Innovation; 2013 [cited 23 Feb 2023]. Available from: https://www1.health.nsw.gov.au/pds/Pages/doc.aspx?dn=GL2014_005
- NSW Emergency Care Institute. Envenomation. NSW, Australia: Agency for Clinical Innovation; 2020 [cited 23 Feb 2023]. Available from: https://aci.health.nsw.gov.au/networks/eci/clinical/clinical-tools/envenomation
- NSW Health. Australian Medicines Handbook. Australia: Australian Government, NSW; 2022 [cited 13 Apr 2022]. Available from: https://amhonline.amh.net.au.acs.hcn.com.au/
- NSW Therapeutic Advisory Group. Life-saving drugs registers. NSW, Australia: NSW Therapeutic Advisory Group; 2021 [cited 23 Feb 2023]. Available from: https://www.nswtag.org.au/life-saving-drugs-register/
- Therapeutic Guidelines. Antiemetic drugs in adults. Australia: Therapeutic Guidelines Limited; 2022 [cited 15 Feb 2023]. Available from: https://tgldcdp.tg.org.au.acs.hcn.com.au/topicTeaser?guidelinePage=Gastrointestinal&etgAccess=true#
| Evidence informed |
Information was drawn from evidence-based guidelines and a review of latest available research. For more information, see the development process. |
| Collaboration |
This protocol was developed by the ECAT Working Group, led by the Agency for Clinical Innovation. The group involved expert medical, nursing and allied health representatives from local health districts across NSW. Consensus was reached on all recommendations included within this protocol. |
| Currency | Due for review: Jan 2026. Based on a regular review cycle. |
| Feedback | Email ACI-ECIs@health.nsw.gov.au |
Accessed from the Emergency Care Institute website at https://aci.health.nsw.gov.au/ecat/adult/snake-or-spider-bite