Morriston Hospital not only relies on ultrasound for many anaesthetic procedures, but also runs a unique hands-on training course and undertakes research studies to help develop the use of the technique
Christian Egeler MD FRCA
Simon Ford MB ChB MRCP FRCA
Morriston Hospital, Swansea, UK
Point-of-care ultrasound technology has come a long way in the last decade, from the early systems with tiny screens producing a grainy image, through to modern state-of-the-art instruments with outstanding resolution. The development of ultrasound technology has been nothing short of phenomenal, and the use of point-of-care ultrasound to guide regional anaesthesia has become very popular.
Regional anaesthesia offers benefits all round
At Morriston, interest in point-of-care ultrasound began with the acquisition of some very basic instruments to meet NICE guidelines for central venous access. However, it soon became clear that these systems would also be ideal for performing nerve blocks and had the potential to revolutionise both regional anaesthesia and chronic pain management. Consequently, like many anaesthesia departments in the UK, we turned to ultrasound for routine hand surgical lists. The financial savings are massive; we recovered the cost of the ultrasound instrument several times over.
Where general anaesthesia requires a dedicated consultant anaesthetist for each theatre list, the use of ultrasound-guided regional blocks allows one anaesthetist to safely and effectively cover two theatres, enabling us to treat as many as eight patients in an afternoon. The system has been in use for seven years now, with a success rate close to 100%. More than 90% of our hand surgical procedures are carried out as day-case patients, maximising throughput efficiency and helping to reduce waiting times. Regional anaesthesia is better for patients too. It allows those unsuitable for general anaesthetic to be treated, time to discharge is much faster and, as the patient is awake and can actually see what is happening, it is far easier to explain the procedure. Most patients engage with the process and find it fascinating.
We are fortunate to have access to a wide range of ultrasound systems – SonoSite’s iLook®, MicroMaxx®, M-Turbo®, S-Nerve™ and the recently launched X-Porte® – benefitting from increasingly advanced technology in additional applications where precise needle placement is essential. One example is the replacement of fluoroscopy imaging with ultrasound guidance in the management of chronic spinal pain interventions. Fluoroscopy outlines the bony structures, allowing the anaesthetist to establish whether the needle is in the optimal position, but several attempts may be necessary to position the needle accurately.
Ultrasound adds an extra dimension to the accuracy of the procedure, enabling visualisation of soft tissue structures and correct needle placement first time, which is far easier for a patient to tolerate. Another big advantage is the increased flexibility it provides; if a patient is unable to adopt the position necessary to perform an X-ray-guided injection, or lie still on the table, the procedure can be adapted to their individual needs while still maintaining accuracy of injection.
As a further benefit, the anaesthetist can see the spread of the injectate and, in many cases, this additional accuracy enables the drug dosages to be reduced, decreasing the risk of side effects and increasing the cost effectiveness of the procedure. Ultrasound also eliminates the repeated exposure of medical staff to radiation which, although very low level, requires a heavy protective gown to be worn. The hospital benefits too: without the need for an expensive X-ray suite or the services of a radiographer, and with fewer staff required, significant cost savings are generated.
A unique approach to ultrasound training
Ultrasound has become such an integral part of diagnosis and interventions that it is crucial to develop this skill as early as possible. At Morriston, we run a unique three-day ultrasound training programme, which can be tailored to match the experience of the trainees, whether novice, intermediate or advanced. The course begins with cadaveric teaching to refresh everyone’s knowledge of anatomy, followed by scanning models of various shapes and sizes to become familiar with visualising the different structures and image acquisition.
The delegates also have the option of performing an ultrasound-guided block on themselves, under close supervision, which is very good experience; it gives them a genuine understanding of what patients go through, and the best way to guide a needle to the target. Finally, senior delegates have the opportunity to perform blocks on patients – with their consent – under our guidance. This unique approach reinforces the training already received, increasing the individual’s confidence in using image-guided regional anaesthesia.
It’s not just UK anaesthetists who take advantage of the ultrasound expertise available at Morriston. We are also a visiting centre with established links to Burma, where ultrasound is a relatively new technology. The Burmese anaesthetists have an outstanding knowledge of anatomy and are brilliant at performing blocks blind or with a nerve stimulator, but their exposure to (and experience with) ultrasound is limited. There is a growing recognition in Burma that ultrasound is going to be the way forward and, by taking up short-term observerships at Swansea, seeing our practices and gaining exposure to the use of the technique, they learn valuable skills to put into practice when they return home.
Developing new approaches to treatment
The precision provided by ultrasound guidance is applicable to all chronic pain interventions, opening up new treatment approaches. In one of our research studies, we used ultrasound to develop a new motor-sparing knee block1 – a series of seven injections around the knee and in the groin, which provide analgesia for knee operations by blocking the sensory nerves, while sparing the motor function of the thigh muscles. This is key to recovery, as it allows earlier, pain-free mobilisation. With the old style nerve block, the patient’s leg is completely numb and heavy for up to 24 hours, which, although good for pain relief, makes mobilisation difficult. This new technique enables injections to be performed before the operation commences, rather than at the end, and early indications are that it is at least as effective as intra-articular injections.
Conclusions
While further studies are necessary, from experience, ultrasound certainly seems to enhance the safety of injection, opening up new possibilities and improving patient experience. Overall, it has transformed regional anaesthesia and chronic pain interventions, proving a cost-saving modality in modern anaesthesia.
Reference
- Egeler C, Jayakumar A, Ford S. Motor-sparing knee block – description of a new technique. Anaesthesia 2013;68(5):542–3.
