Advanced vascular ultrasound prior to radial artery cannulation on the intensive care unit: A feasibility service evaluation.

Background: Radial arterial catheters are frequently used for monitoring and blood sampling in critical care patients. Ischaemic complications are rare but can cause significant morbidity. The use of vascular ultrasound in critical care is becoming increasingly commonplace. This service evaluation aims to assess the feasibility of training novices in advanced vascular ultrasound assessment, prior to radial arterial cannulation.

Methods: Over a 4-month period, data was collected from patients admitted to the intensive care unit at the William Harvey Hospital, Ashford, Kent. Ultrasound was used to assess for the presence, size and flow of the radial and ulnar arteries. The assessments were performed by two novice residents in intensive care, who were trained in advanced ultrasound assessment of the radial and ulnar arteries, by an intensive care consultant with expertise in vascular ultrasound.

Results: One hundred and five limbs were assessed in 53 patients. Novices were deemed to be sufficiently competent, after performing scans on 15 patients over a 2-week period. Satisfactory images were acquired in 100% of patients. The most common finding was a small diameter ulnar artery, present in 30 limbs (29%), while only 1 patient (1%) was found to have an absent ulnar artery. Thirty-two limbs had a radial arterial catheter in-situ. There were no ischaemic complications.

Conclusion: This service evaluation demonstrates that the training of novices in advanced ultrasound assessment of the radial and ulnar arteries by an intensive care consultant, is feasible. Moreover, this modality may identify patients at risk of critical limb ischaemia. This particular investigation may be considered for incorporation into existing vascular ultrasound assessments.