Andrew Thelwell is Chief Commercial Officer at Sky Medical Technology, the developer of the geko™ device, used globally to address complications related to swelling following orthopaedic surgery, trauma, and kidney transplant. In this article he discusses the burden oedema places on healthcare systems, clinicians and patients, the historic lack of solutions and why the geko™ device may help to provide an answer.
What is oedema?
Oedema is swelling caused by excess fluid that has leaked from the vascular system and becomes trapped in the body’s tissues. It can affect any part of the body and can impede recovery from illness or operation1.
There are several different sub types of oedema – such as pulmonary and cerebral – but this article focuses on Peripheral oedema, as it is in this category that our company, Sky Medical Technology, is focussed on. The geko™ device is a small electronic medical technology device – about the size of a wristwatch – that can address complications related to pre and post-operative swelling following orthopaedic surgery, trauma and kidney transplant.
Why is oedema a problem?
Oedema can delay early patient intervention, early discharge and impede patient recovery2. For the past 10 years, a major focus for healthcare systems has been to move people out of the hospital environment as quickly as possible. This has three benefits: it means healthcare systems can treat people more quickly; it reduces the cost of hospital stays – one of the most expensive aspects of healthcare; and it enables people to recover in the familiar comfort of their own home3. This objective, however, can be negatively impacted by the effect of unresolved oedema2.
As an example, in the Trauma setting, consider the impact of oedema on a patient with an ankle fracture. An ideal scenario is to operate as soon as possible after a patient presents at hospital. The earlier the intervention, the better the likely bone repair and the sooner rehabilitation can begin. This ideal, however, is confounded by the presence of initial oedema, which can then increase over the first 24-48 hours post fracture4. Ankle trauma patients most often arrive in A&E with oedema build-up already established. In these circumstances, patients who are unable to be sent home to elevate, due to clinical and social circumstances, require in-patient bed rest to elevate the ankle and therefore reduce swelling to an acceptable level to operate5. This scenario can cause bed blocking. Interventions that reduce pre-operative swelling and accelerate readiness to surgery can therefore provide significant benefits to both patients and healthcare providers.
This also applies to post-operative oedema management. Patients’ with comorbidities and compromised vasculature are at greater risk of complications related to swelling following lower limb orthopaedic surgery6. Impaired calf muscle pump function, the result of immobility and/or venous insufficiency, can cause ineffective venous return, reducing the delivery of blood to the tissue, impacting surgical wound healing and muscle function7.
Following knee replacement surgery, post-operative oedema can also block nerve to muscle signals, diminishing quadriceps muscle strength and reducing input to the surrounding muscles by activating mechanisms within the central nervous system that can change the discharge of sensory receptors preventing the quadriceps muscle from being fully activated, thereby causing muscle weakness and loss of muscle function8.
Although patients are being discharged earlier than in the past, a published study by Kelly et al, which sought to identify common reasons for 90-day emergency department (ED) visits following total joint arthroplasty (TJA), reports post-operative swelling as one of the top three surgery related reasons for post-operative complications, following total knee arthroplasty (TKA) and total hip arthroplasty (THA). One in ten patients return to ED within 90 days of TJA, incurring costs for clinician time and diagnostic scans/tests to determine and prescribe appropriate treatments9.
How do we tackle oedema?
In the UK, the current pre-operative standard of care in ankle-facture patients requiring surgical fixation is elevation plus a backslab plaster cast, either alone or with external fixation, or elevation plus a backslab plaster cast with mechanical pneumatic compression (IPC) fitted beneath the cast. IPC is a boot-like cuff that compresses the leg to increase blood flow. It is not suitable, however, for all patients due to vascular disease, fragile skin, or complex limb injury and fitting IPC beneath a backslab is also uncomfortable10.
IPC is also used post-operatively following TJA surgery, as is the non-pharmaceutical option Cryotherapy, which has evolved from simple ice sleeves (or gel packs), to more refined devices employing electronically controlled cold fluid or air circulation. Both are used in the immediate post-operative period and while they provide some benefits, their use is controversial 2, 11 and both require resources to correctly fit the devices. Furthermore, the pneumatic pumps that operate the cuffs are not always readily available.
Speaking to this huge, and until now, silent unmet burden, with few tools to address the complications – which can delay surgery, impede wound closure, decrease muscle strength and stall rehabilitation – is the innovative geko™ device, developed by Sky Medical Technology.
How the geko™ device provides a solution for oedema?
To solve this oedema burden, consider the vascular nature of the condition, and how increasing blood flow in a lower limb can provide the key for swelling reduction pre and post-operatively and in non-surgical patients2.
Through its innovative mechanism of neuromuscular electrostimulation, the battery powered, geko™ device, is applied non-invasively to the skin over the common peroneal nerve at the side of the knee. It gently stimulates the nerve, once every second, activating the calf and foot muscle pumps resulting in unparalleled, increased blood flow in the deep veins of the calf12, at rate equal to 60% of walking13, without a patient having to move. This unique mechanism of action – the combination of calf muscle activation and blood flow increase – is clinically proven to reduce both fluid leakage in the capillary bed and to enable oedema clearance by local reabsorption of excess interstitial fluid via the vasculature and lymphatic system10, 14.
Initially the intended use of the geko™ device had not been oedema management. The discovery that it could positively impact oedema reduction was a stroke of luck. While working with Orthopaedic clinical partners, who were exploring use of the geko™ for post-operative venous thromboembolism (VTE) prevention, its effect on oedema reduction was first observed.
This led to the completion of several studies. A pre-operative, prospective and retrospective audit of clinical practice, in partnership with the James Cook University Hospital, part of the South Tees Hospitals NHS foundation trust in Middlesbrough. The clinical team, led by Mr Paul Baker, Orthopaedic Consultant Surgeon10, measured the time to surgery in 20 ankle facture patients requiring surgical fixation and their tolerance to the geko™ device. The results showed accelerated time to theatre – a statistically significant two-day reduction in readiness for surgery (on average) – with all patients reporting the geko™ device as well tolerated. Noticeably, patients were able to mobilize more easily, for toilet visits or visits the coffee shop, with the device still active. Where previously, IPC hoses and leads would have tethered these patients to the bed, requiring a nurse to first unplug the leads.
A published RCT (randomized controlled trial) by Wainwright et al14 followed, demonstrating the geko’s post-operative oedema control credentials. The study compared the effect of the geko™ device to TED Stockings (standard care) in 40 total hip replacement patients and reported the prevention of oedema build-up post-operatively – again, with all patients reporting the device as well tolerated.
In a US study, the geko™ device is also being used by patients in the home. Participating hospitals are fitting the device in the recovery room to the affected limb, immediately post-surgery, for 24 hours. When the patients are ready to go home, they are then trained to self-apply the device and are provided with treatment packs for nine days geko™ device use to maintain oedema prevention.
The geko™ device has also found success outside of orthopaedics. A published study from Lawson Health Research Institute (LHSC), Ontario, Canada, led by Dr Alp Sener15, found the geko™ device is effective in reducing swelling after kidney transplantation. The RCT, spanning two years and 221 transplant patients, compared geko™ device impact to compression stockings and IPC, for six days wear following surgery. The results show that use of geko™ device alone increased urine output by 27 per cent and lowered weight gain by over a kilogram. With more urine produced and less fluid retention, patients experienced 31 per cent less oedema and the duration of costly hospitalisation was shortened by more than one day after kidney transplantation, compared to standard care.
This existing data and an ongoing program of studies serve to demonstrate geko™ device efficacy and offers, for the first time, an innovative medical intervention – where previously few or no effective tools have been available – that is easy to use and clinically proven and can provide clinicians and patients with the means to manage both surgical and non-surgical related oedema, for accelerated patient intervention, earlier patient discharge and enhanced patient recovery.