Efficacy of Prehospital Tourniquet Models for Arterial Occlusion in Upper and Lower Limbs

Summary

The goal of this clinical trial is to compare the occlusive capability and mechanical behavior of different commercially available pre-hospital tourniquet models and the results of their application on upper and lower limbs, in order to validate the techniques proposed in international guidelines regarding proximal application on the arm and thigh ("high and tight tourniquet") and controlled application, 2 to 3 inches proximally to the injury, on the forearm and leg ("controlled tourniquet").

It is estimated that 40 volunteer individuals will be recruited, who will sign the Informed Consent Form (ICF), a group primarily composed of undergraduate and graduate students in health-related fields. Regarding inclusion and exclusion criteria, these individuals will be of both sexes, aged ≥18 and ≤60 years, with both upper and lower limbs, a Body Mass Index (BMI) ≥18.5 and ≤30 kg/m² (considering the normal and overweight range, excluding underweight and obesity ranges), and without Diabetes Mellitus (DM), Systemic Arterial Hypertension, Buerger's disease, vascular and metabolic dysfunctions affecting the limbs including lymphedema, history of neoplasms, cardiac surgeries, renal failure, recent open or closed injuries in the limbs, or any other condition suggestive of systemic or localized vascular dysfunction in the limbs.

The main questions it aims to answer are:

Null Hypothesis (H0): There are no significant differences in the occlusive capability between TQs and in the efficacy of total vascular occlusion (arteriovenous) depending on the application site among the segments (forearm, arm, leg, thigh).

Alternative Hypothesis (H1): There are significant differences in the occlusive capability between TQs and in the efficacy of total vascular occlusion (arteriovenous) depending on the application site among the segments (forearm, arm, leg, thigh).

Specific Hypothesis: TQs will present significant variations in initial tightening pressures, arterial occlusion times, and arterial occlusion pressures, evidencing differences that may affect their efficacy.

Each participant will receive a total of 8 TQ applications on the arm, forearm, leg, and thigh segments bilaterally, for each of the 3 non-consecutive collection days. Vascular occlusion will be verified using Doppler ultrasound on the radial artery for upper limbs and on the posterior tibial artery for lower limbs.

It is a cross-sectional and self-controlled trial, aimed at collecting primary data, with randomization of the application order regarding device, laterality, segment, and blinding of the statistical analyst regarding the applied tourniquet model.

Conditions

• Hemorrhage
• Hypovolemic Shock
• Tourniquets

Interventions

DEVICE

TQ - Proximal Application ("high and tight")

Tourniquet application: proximal ("high and tight") on arms and thighs.

DEVICE

TQ - Controlled application (2-3 inches)

TQ Application: controlled (2-3 inches proximal to the injury) on forearms and legs.

Sponsors & Collaborators

• University of Sao Paulo

  lead OTHER

Principal Investigators

• Roger W F Ronconi, PT, MSc, PhD(c) · Faculdade de Medicina de Ribeirão Preto da USP (FMRP-USP)

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

SEQUENTIAL

Eligibility

Min Age

18 Years

Max Age

60 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2024-12-07

Primary Completion

2026-12-31

Completion

2026-12-31

FDA Device

Yes

Countries

• Brazil

Study Locations