💡Introduction

As an emergency physician or emergency nurse, it is not uncommon to encounter patients with difficult peripheral IV access. Ultrasound guidance significantly improves IV access first attempt success rate in these patients. This e-learning website aims to provide knowledge including patient selection, image optimization and safe cannulation technique. This website is designed for viewing on mobile devices. You can add to homescreen to install it as an web application.

Watch the brief introduction video sent to you for an overview of the contents covered in this website.

📚Definition

A difficult IV access is typically defined by one or more of the following:

1. More than two attempts are required for successful cannulation.
2. A prior history of difficult access or failed attempts.
3. No visible or palpable veins after tourniquet application.
4. Clinical risk factors such as obesity, chronic illness, edema, or IV drug use.

🧮Prediction tools

Several clinical tools can help predict difficult access and prioritize patients for ultrasound guidance.

DIVA scales

There are several validated scales that uses clinical predictors to estimate the likelihood of failed peripheral IV placement in adults. Multiple iterations of the Difficult IV Access Scales were published, including the Addictive DIVA Scale, the Comprehensive DIVA Scale, the Enhanced Adult DIVA Scale and the Modified DIVA Scale. This module recommended the use of the Modified DIVA scale for its simplicity and ease of use.

Modified A-DIVA Scale

The Modified A-DIVA Scale uses five criteria, each worth one point.

1. Known history of difficult IV access.
2. Expectation of a failed first attempt or difficult access.
3. Inability to palpate a vein.
4. Inability to visualize a vein.
5. Largest vein diameter < 3 mm.

Predicted Success Rates by Score:

• Score 0: 98%
• Score 1: 90%
• Score 2: 69%
• Score 3: 55%
• Score 4: 14%
• Score 5: 2%