Analysis of the Efficacy of Pressure Pad vs Pressure Bandage Immobilisation for Snake Bite First Aid in Healthy Volunteers.

NCT07261982 | Recruiting

• 1 other identifier: EMLE-280R41-2024-HOLYOAK
• Study Type: interventional
• Target: 24
• Locations: 1 country
• Sites: 1

Brief Summary

Snake bite affects thousands of Australians every year, but few die as a result due to high quality first aid and timely medical care. Good first aid should be simple, standardised, use minimal or readily available equipment, and be able to be utilised effectively with no or minimal training by the rescuer. Over time the first aid methods used to manage snake bite in Australia have been questioned due to issues with efficacy, and some emerging evidence of harm from their use. There is little experimental data in the literature to support current first aid practices, and what exists suggests further research is required. This study aims to examine and compare the effectiveness of two first aid methods by tracking the movement of a mock venom through the body when each first aid method is used. This will provide important information about the suitability of current techniques used in Australia and whether a proposed simpler alternative technique is as effective. Currently, initial treatment of snake bite involves early first aid with the application of a pressure bandage and immobilisation (PBI) of the limb. There is limited data to support the basis of this technique and emerging evidence of harm when applied incorrectly. This project sets out to evaluate PBI compared to another technique involving the application of a pressure pad (PP) at the bite site (which is easier to do, and used in many countries outside of Australia). The project aims to determine whether each technique is effective, and whether the PP technique is at least as effective as PBI. To do this 24 participants will be recruited to undergo study with mock venom injected into their hand or foot and having either PBI or PP applied. The mock venom will then be traced with a gamma camera to determine rate of flow through the lymphatic system, which is how venom travels in the body. It is expected that the project will demonstrate the efficacy of both techniques, and that the PP will be at least as effective as PBI. This will provide a basis for change in the current first aid recommendations for snake bite first aid in Australia, and improve the care provided.

Conditions

Snake Bites; Snakebite; Snake Envenomation; Snake Bite; First Aid

Keywords

Snakebite; First aid; Pressure bandage immobilisation; Pressure pad

Outcome Measures

Primary Outcomes (1)

• Time for mock venom to reach regional lymph nodes following injection

  Time (in seconds) will be recorded from the injection of Tn-99m sulfur colloid until signal is detected at the regional lymph nodes for the relevant limb, and then until there is evidence of entry to the systemic circulation (as demonstrated by signal detection in the liver). Times will be judged by the reporting radiologist on the basis of the time stamp on the relevant image relating to signal detection at the relevant location. Each scan will run for up to 30 minutes, with intervention scans having the first aid technique removed at this point and running for a further 30 minutes. This allows demonstration of movement of mock venom through the lymphatic system after removal of first aid if the initial application of first aid is efficacious enough to completely retard mock venom movement. Distance from injection site to either groin or axilla (as relevant) will also be measured at each scan so that a lymphatic flow rate is able to be calculated

  From the date of enrolment until all scans are completed (minimum of 12 weeks, maximum of 18 months).

Study Arms (1)

Comparison of control, pressure bandage immobilisation and pressure pad first aid techniques

EXPERIMENTAL

Each subject will be injected with mock venom in either their hand or foot and then either no first aid (control), pressure bandage immobilisation, or pressure pad first aid techniques will be applied. The passage of mock venom (Technetium-99m sulphur colloid) through the subject's lymphatic system will be tracked by nuclear medicine imaging. Each subject will undergo repeated scans each using a different location/first aid method so that all subjects will have data on all six possible permutations in a randomised order. Time in seconds for the mock venom to travel to regional lymph nodes in the relevant limb will be recorded and compared across the different first aid techniques.

Other: Pressure bandage immobilisation first aid; Other: Pressure pad first aid; Other: Control - no first aid

Interventions

Pressure bandage immobilisation first aid OTHER

Pressure Bandage Immobilisation Technique (PBI): 1. An elastic bandage of 100mm width will be applied to the full length of the involved limb, starting from the fingers or toes and moving proximally until the whole limb is bandaged, bandaging over clothing if required. 2. The desired pressure of the bandage (\~60mmHg) will be obtained by utilising "smart" bandages which have special markings that take on the shape of a square when the bandage is applied at this pressure/tension. Prior to use on each subject, the accuracy of this process will be confirmed via pressure manometry using an infant blood pressure cuff bladder placed under the wraps of the elastic bandage and connected to a manometer as per Canale et al. 3. Splinting of the limb will be performed using a sling for the arm, and a wooden splint for the leg.

Comparison of control, pressure bandage immobilisation and pressure pad first aid techniques

Pressure pad first aid OTHER

Pressure Pad Technique (PP): 1. A square gauze pad of 5 sheets thickness with an overall size of 80x80mm will be applied to the injection site. 2. The gauze pad will be secured using an elastic bandage of 100mm width at a tension of \~60mmHg using a "smart" bandage. Prior to use on each subject, the accuracy of this process will be confirmed via pressure manometry using an infant blood pressure cuff bladder placed under the wraps of the elastic bandage and connected to a manometer as per Canale et al. 3. Splinting of the limb will be performed using a sling for the arm, and a wooden splint for the leg.

Comparison of control, pressure bandage immobilisation and pressure pad first aid techniques

Control - no first aid OTHER

Control (no first aid technique applied): 1. Imaging will be done with the subject lying supine and still without the application of either bandaging technique 2. Splinting of the limb will be performed using a sling for the arm, and a wooden splint for the leg.

Comparison of control, pressure bandage immobilisation and pressure pad first aid techniques

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years old or greater
• No known or clinically evident lymphatic condition (eg. lymphoedema, lymph node surgery etc)
• No known cardiac failure
• No known peripheral vascular disease
• No known renal or hepatic impairment
• No known lymphoma

You may not qualify if:

• Age less than 18 years old
• Pregnant
• Breast feeding
• Allergy to Technetium-99m sulphur colloid

Sponsors & Collaborators

• Townsville University Hospital: lead

Study Sites (1)

Queensland X-Ray

Hyde Park, Queensland, 4812, Australia

RECRUITING

Related Publications (19)

• Sutherland SK. The pressure immobilisation technique. Med J Aust. 1994 Dec 5-19;161(11-12):700-1. No abstract available.

  PMID: 7830642 BACKGROUND

• Smith H. Uptake of "mock-venom". Med J Aust. 1982 Jul 24;2(2):66

  BACKGROUND

• Anker RL, Straffon WG, Loiselle DS, Anker KM. Snakebite. Comparison of three methods designed to delay uptake of 'mock venom'. Aust Fam Physician. 1983 May;12(5):365-8.

  PMID: 6351824 BACKGROUND

• Pe T, Mya S, Myint AA, Aung NN, Kyu KA, Oo T. Field trial of efficacy of local compression immobilization first-aid technique in Russell's viper (Daboia russelii siamensis) bite patients. Southeast Asian J Trop Med Public Health. 2000 Jun;31(2):346-8.

  PMID: 11127337 BACKGROUND

• Tun-Pe, Aye-Aye-Myint, Khin-Ei-Han, Thi-Ha, Tin-Nu-Swe. Local compression pads as a first-aid measure for victims of bites by Russell's viper (Daboia russelii siamensis) in Myanmar. Trans R Soc Trop Med Hyg. 1995 May-Jun;89(3):293-5. doi: 10.1016/0035-9203(95)90547-2.

  PMID: 7660439 BACKGROUND

• Little M. Harm due to the use of pressure bandage immobilisation in patients bitten by snakes in Australia. Clin Toxicol (Phila). 2023 Aug;61(8):611-612. doi: 10.1080/15563650.2023.2252586. Epub 2023 Sep 5.

  PMID: 37668172 BACKGROUND

• Pressure/immobilisation first aid treatment of snake bite. Med J Aust. 1982 Feb 20;1(4):155, 157. No abstract available.

  PMID: 7078485 BACKGROUND

• Pearn JH, Morrison JJ, Charles NT. First aid in snake bite; comment on mock venom. Med J Aust. 1982 Jul 24;2(2):65-6. doi: 10.5694/j.1326-5377.1982.tb124243.x. No abstract available.

  PMID: 7121362 BACKGROUND

• Parker-Cote J, Meggs WJ. First Aid and Pre-Hospital Management of Venomous Snakebites. Trop Med Infect Dis. 2018 Apr 24;3(2):45. doi: 10.3390/tropicalmed3020045.

  PMID: 30274441 BACKGROUND

• Anker RL, Straffon WG, Loiselle DS, Anker KM. Retarding the uptake of "mock venom" in humans: comparison of three first-aid treatments. Med J Aust. 1982 Mar 6;1(5):212-4. doi: 10.5694/j.1326-5377.1982.tb132272.x.

  PMID: 7087836 BACKGROUND

• Sutherland SK, Coulter AR, Harris RD. Rationalisation of first-aid measures for elapid snakebite. Lancet. 1979 Jan 27;1(8109):183-5. doi: 10.1016/s0140-6736(79)90580-4.

  PMID: 84206 BACKGROUND

• Rogers IR, Winkel KD. Struan Sutherland's "Rationalisation of first-aid measures for elapid snakebite"--a commentary. Wilderness Environ Med. 2005 Fall;16(3):160-3. doi: 10.1580/er20-04.1. No abstract available.

  PMID: 16209471 BACKGROUND

• Currie BJ, Canale E, Isbister GK. Effectiveness of pressure-immobilization first aid for snakebite requires further study. Emerg Med Australas. 2008 Jun;20(3):267-70. doi: 10.1111/j.1742-6723.2008.01093.x.

  PMID: 18549384 BACKGROUND

• Canale E, Isbister GK, Currie BJ. Investigating pressure bandaging for snakebite in a simulated setting: bandage type, training and the effect of transport. Emerg Med Australas. 2009 Jun;21(3):184-90. doi: 10.1111/j.1742-6723.2009.01180.x.

  PMID: 19527277 BACKGROUND

• Welton RE, Liew D, Braitberg G. Incidence of fatal snake bite in Australia: A coronial based retrospective study (2000-2016). Toxicon. 2017 Jun 1;131:11-15. doi: 10.1016/j.toxicon.2017.03.008. Epub 2017 Mar 10.

  PMID: 28288937 BACKGROUND

• Howarth DM, Southee AE, Whyte IM. Lymphatic flow rates and first-aid in simulated peripheral snake or spider envenomation. Med J Aust. 1994 Dec 5-19;161(11-12):695-700.

  PMID: 7830641 BACKGROUND

• Seifert SA, Armitage JO, Sanchez EE. Snake Envenomation. N Engl J Med. 2022 Jan 6;386(1):68-78. doi: 10.1056/NEJMra2105228.

  PMID: 34986287 BACKGROUND

• Norris RL, Ngo J, Nolan K, Hooker G. Physicians and lay people are unable to apply pressure immobilization properly in a simulated snakebite scenario. Wilderness Environ Med. 2005 Spring;16(1):16-21. doi: 10.1580/PR12-04.1.

  PMID: 15813142 BACKGROUND

• Avau B, Borra V, Vandekerckhove P, De Buck E. The Treatment of Snake Bites in a First Aid Setting: A Systematic Review. PLoS Negl Trop Dis. 2016 Oct 17;10(10):e0005079. doi: 10.1371/journal.pntd.0005079. eCollection 2016 Oct.

  PMID: 27749906 BACKGROUND

Related Links

• World Health Organisation. Snakebite envenoming.
• Australian Venom Research Unit. FAQ: How common is snakebite in Australia
• Australian Venom Research Unit. The global scale of snakebite. Snakebite envenoming: a neglected tropical disease
• 16\. Australian Resuscitation Council. Envenomation - pressure immobilisation technique
• Australian Resuscitation Council. Aims and objectives of the ARC

MeSH Terms

Conditions

Snake Bites

Condition Hierarchy (Ancestors)

Bites and Stings; Poisoning; Chemically-Induced Disorders; Wounds and Injuries

Study Officials

• Adam L Holyoak

  Townsville University Hospital

  PRINCIPAL INVESTIGATOR

• Mark Little

  Cairns Hospital

  PRINCIPAL INVESTIGATOR

• Tyson Reeve

  Queensland X-Ray

  PRINCIPAL INVESTIGATOR

• Jade Bax

  Queensland X-Ray

  PRINCIPAL INVESTIGATOR

• Theophilus I Emeto

  James Cook University, Queensland, Australia

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Adam L Holyoak

CONTACT

+61423852272; adam.holyoak@health.qld.gov.au

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Senior Staff Specialist

Model Details: Data analysis will be undertaken by the research team which includes a biostatistician. For a standard two-period, two-sequence cross-over design, the investigators anticipate a sample size of N=24 will achieve 91% power at a 5% significance level assuming the absolute difference between the two-treatment means is 1 minute and the within-subject standard deviation is 1 minute. This will allow detection of significant differences between all interventional scans and controls and determine the efficacy of each first aid technique. A \>90% power has been chosen due to the paucity of data in the literature to guide better predict effect size.

Study Record Dates

• First Submitted: November 17, 2025
• First Posted: December 3, 2025
• Study Start: July 18, 2025
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): February 1, 2027
• Last Updated: December 16, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, CSR
• Time Frame: IPD will be provided on request upon completion of the study and will be available for up to 10 years following completion of the study. Supporting information will be available as or when available until 10 years following completion of the study.
• Access Criteria: Parties wishing to access the IPD will be able to do so by contacting the primary author of the study, and will be provided with the relevant data etc as required

Locations

AU (1)