Managing Difficult IV Cannulation
Published: 18 October 2023
Published: 18 October 2023
Intravenous cannulation in prehospital settings enables the delivery of medicine, intravenous fluids, anesthesia, and other interventions prior to patient transportation (Prottengeier et al. 2016).
However, cannulation may be difficult and is associated with a high risk of complications. If the cannulation fails, this may further delay treatment and transport, potentially resulting in adverse patient outcomes (Prottengeier et al. 2016; QAS 2022).
How do you tell whether cannulation will be ‘difficult’, and how does this affect patient management and clinical decision-making?
Difficult intravenous access (DIVA), or difficult peripheral intravenous cannulation (DPIVC), describes a situation wherein a practitioner is having difficulty gaining peripheral vascular access, often because the patient's veins cannot easily be seen or felt (Rodriguez-Calero et al. 2020; Sou et al. 2017). It is generally defined as:
(Rodriguez-Calero et al. 2020)
Difficult cannulation is troublesome for a number of reasons:
(Sou et al. 2017; Sonosite 2018; Rodriguez-Calero et al. 2020; RCHM 2019)
Environmental factors such as poor lighting - which may be impossible to control in prehospital settings - may also contribute to poor vein visibility (Prottengeier et al. 2016).
Patients who might be difficult to cannulate include:
(Emcare 2016; Lamperti & Pittiruti 2013; Sonosite 2018; Chiao et al. 2013; Olberon 2017)
The difficult intravenous access (DIVA) score can be used to predict the likelihood of failing an initial cannulation in pediatric patients (Shaukat et al. 2019).
This is an important tool, as multiple attempts at cannulation may cause distress and pain to children (RCHM 2019).
If the patient scores four or more points in total, the initial cannulation has a greater than 50% chance of failing (RCHM 2019).
Predictor | 0 Points | 1 Point | 2 Points |
Visible vein | Visible | - | Not visible |
Palpable vein | Palpable | - | Not palpable |
Patient's age | Over 36 months | 12 to 35 months | Under 12 months |
(Adapted from RCHM 2019)
For a comprehensive guide to IV cannulation, see Venepuncture: Phlebotomy and IV Cannula Insertion.
Options for cannulation sites in prehospital settings include:
(QAS 2022)
In critical emergency situations, the cannulation of the jugular vein may also be considered. It is, however, important to posture the patient properly in order to minimize the risk of air emboli.
Should all IV cannulation attempts fail, then intraosseous access via appropriate devices (e.g. EZI-IO) is a viable option. In some jurisdictions, this is already the go-to method in cardiac arrest.
Generally, the most suitable site for pediatrics is the dorsum of the non-dominant hand (RCHM 2019).
You should make a maximum of two cannulation attempts (refer to your organization's policy) (QLD DoH 2015).
Assess the urgency of the situation. If the patient immediately requires IV access (critical situation):
(RCHM 2019)
Note that the use of the following strategies will depend on the urgency of the situation and the patient's condition.
(Tan et al. 2015)
Cannulation can be distressing for infants. The following tips may help the patient feel more comfortable:
(Starship 2021)
It may be worth assessing whether it is possible to delay cannulation until IV access can be established using ultrasound guidance in the hospital, as this will be easier. You may also consider:
(QAS 2021)
Vasomotor changes due to the patient being cold, hypotensive, or nervous may mean the veins require more time to dilate. Try:
(Emcare 2016)
You may accidentally pass the cannula through the opposite wall, which will cause blood backflow to cease when you remove the stylet. Try:
(Emcare 2016)
Never attempt to reinsert the stylet.
Try adjusting the angle of entry. Remove and reassess if this still proves unsuccessful. Remember not to make more than two attempts at cannulation (Emcare 2016).
Attaching a saline-filled syringe to the catheter and gently flushing may help. If you feel no resistance, you can advance the cannula while continuing to flush. If this is unsuccessful, remove the cannula and try a different site (Emcare 2016).
This increases the likelihood of tissue trauma and cannulation failure. Try:
(Emcare 2016)
During cannulation, the vein may involuntarily contract, causing sharp pain and skin blanching. This may result in trauma. Try:
Note: This article is intended as a refresher and should not replace best-practice care. Always refer to your organisation's policy on IV cannulation.
Question 1 of 3
What is the maximum amount of cannulation attempts that should be made for a paediatric patient?