How a Medico-Legal Expert Witness Evaluates Suspected Extravasation Injuries

Was It an Injury or a Complication? A Medico-Legal Expert Witness Review

In intensive care settings, outcomes often fall into grey areas. When a patient develops skin damage near a cannula site post-surgery, clinical teams face a dilemma and legal teams ask: Was this a foreseeable event? Should nursing staff have done more?

The focus in this case, reviewed by a medico-legal expert witness from Apex Experts, centered on a suspected extravasation injury in a high-dependency unit, where a peripheral cannula had displaced and skin damage later emerged. The central claim was that nurses breached their duty by not recognising the signs of injury earlier.

Medico-Legal Expert Witness Review: Injury Does Not Automatically Means Negligence

The Claimant alleged that once the cannula was found dislodged on 31 August, staff should have suspected leakage into surrounding tissue. However, our expert reviewed records showing:

• VIP scores of 0 were documented consistently for four days

• No redness, pain, swelling, or other extravasation signs were present

• No known vesicant drugs were administered through that cannula

  
  

“Displacement of a cannula is common in ICU settings. Without clinical signs or high-risk drugs, there is no duty to assume extravasation,” — Apex Medico-Legal Expert Witness

In fact, ICU norms dictate that vasopressors like Noradrenaline are given centrally, not peripherally, and the records suggest this protocol was followed.

The Importance of Cannula Site Monitoring and Documentation

Though injury occurred, our medico-legal expert witness clarified that the nursing team had followed standard observation protocols, using VIP scoring (Visual Infusion Phlebitis) to track cannula site health.

This case illustrates how strong documentation can support the defence of a negligence claim, especially when VIP tools and central line protocols are followed correctly.

Legal and Clinical Takeaways

For NHS Trusts, private hospitals, and defence solicitors, this case reinforces three key principles:

1. Injury is not proof of breach, the question is whether the nurse acted as a responsible clinician would (Bolam test).

2. Extravasation suspicion requires known vesicant use or visible symptoms.

3. ICU environments demand consistent documentation, especially when multiple infusions, cannulas, and access lines are in use.

Guidelines such as the RCN IV Therapy Standards and NHS Injectable Medicines Guide are essential references for best practice.