What are the risk factors for extravasation?

Risks for extravasation include factors relating to patients, procedures carried out and drugs administered.

Patient-related factors:

  • Very young and elderly patients who have small and fragile veins
  • Patients with thickened and damaged veins following repeated IV access, for example cancer patients
  • Patients with veins that made venous access difficult (Kim et al 2020):
  • Patients with excised lymph nodes, limb amputation, or closed vena cava
  • Obese patients in which peripheral venous access is more difficult
  • Patients who are unable to remain still e.g., young children or patients with behavioural issues
  • Patients receiving anticoagulants may lose more blood if extravasation occurs
  • Patients on sedatives or analgesics may not notice the early signs or symptoms of extravasation
  • Procedure-related factors:

Inadequately trained or inexperienced staff

  • Multiple attempts at cannulation
  • Inappropriate selection of equipment such as type of catheter or size of needle
  • Poor fixation technique

Drug-related factors: Drugs can be categorised for risk of tissue damage based on their osmolarity, pH and whether or not they are a vesicant 


  • Osmolarity >600 mOsm/L
  • pH <4 or >9
  • Vesicant drug


  • Osmolarity 450–600 mOsm/L
  • pH 4 to 5 or 7.5 to 9
  • Non-vesicant drug


  • Osmolarity <450 mOsm/L,
  • pH 5 to 7.5
  • Non-vesicant drug