5th October 2021
Discussed in this latest blog is the burden oedema can place on healthcare systems, clinicians and patients, the historic lack of solutions and why the geko™ device can help 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. The focus in this blog, however, is peripheral oedema, as it is in this category our company Sky Medical Technology has deployed geko™, a non-invasive, neuromuscular electrostimulation (NMES) device that increases blood flow in the deep veins of the calf2 to reduce pre and post-operative oedema related to trauma and orthopaedic surgery.
Why is oedema a problem?
Oedema is a problem in that it can delay early patient intervention, early discharge and impede patient recovery2. For many years, a major healthcare system objective has been to move patients out of the hospital environment to manage their recovery at home3 providing the benefit of reduced length of hospital stay, decreased infection risk, increased bed turnover and lower costs4,5. This objective, however, can be negatively impacted by the effect of unresolved oedema2.
A good example of this is ankle fracture patients in a trauma setting. The ideal scenario is to operate soon after the patients present at hospital. The earlier the intervention, the better the bone repair and the sooner rehabilitation can begin. This ideal, however, can be confounded by the presence of oedema, which can increase over the first 24-48 hours post-fracture6. Ankle trauma patients most often arrive in the ER/ED with oedema build-up already well established. In these circumstances, patients who are unable to be sent home to elevate (due to clinical and social circumstances), may require in-patient bed rest to elevate the ankle to reduce swelling to an acceptable level to operate7. In this scenario patients can become bed blockers. Interventions that can reduce pre-operative swelling to accelerate readiness to surgery, therefore provide significant benefits for both the 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 surgery8. 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 function9.
Following knee replacement surgery, post-operative oedema can also block nerve to muscle signals, diminishing quadriceps muscle strength. Oedema reduces 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 function10.
Although patients are successfully being discharged earlier, 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 total joint arthroplasty (TJA), incurring costs for clinician time and the diagnostic scans and tests to determine and prescribe appropriate treatments11.
How do we tackle oedema?
In the UK, the current pre-operative standard of care for 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 pneumatic 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 uncomfortable12.
IPC is also used post-operatively following TJA surgery, as is another 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 MedTech devices are used in the immediate post-operative period and while they provide some benefits, their use is controversial 2,13 and both require resource 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 need, with few tools to address the complications – which can delay surgery, impede surgical wound closure, decrease muscle strength and stall rehabilitation – is the innovative geko™ device.
How the geko™ device provides a solution for oedema?
To help solve the peripheral oedema burden, our company first considered the vascular nature of the condition, and how increasing blood flow in a lower limb might provide the key to swelling reduction, both pre and post-operatively and in non-surgical patients2.
Through an innovative mechanism of neuromuscular electrostimulation, the battery powered, geko™ device, which is applied non-invasively to the skin over the common peroneal nerve at the side of the knee, gently stimulates the nerve, once every second, activating the calf and foot muscle pumps, increasing blood flow in the deep veins of the calf2 at rate equal to 60% of walking14, without a patient having to move. Through this unique mechanism of action – a combination of calf muscle activation and blood flow increase – we have clinically proven the geko™ device can reduce fluid leakage in the capillary bed and promote oedema clearance by local reabsorption of excess interstitial fluid via the vasculature and lymphatic system15.
Initially, the intended use of the geko™ device had not been oedema management. The discovery that it could positively treat and prevent oedema was a stroke of luck. While working with Orthopaedic clinical partners, who were exploring use of the geko™ for venous thromboembolism (VTE) prevention, its effect on oedema reduction was first observed.
This led to the completion of several studies, notably, a pre-operative prospective and retrospective audit of clinical practice in ankle fracture patients, 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 Surgeon12, measured the impact of geko™ device use on the time to surgery and patient tolerance, in 20 ankle facture patients requiring surgical fixation. The results showed accelerated time to surgery – a statistically significant two-day reduction in readiness for surgery (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 the patients to the bed, requiring a nurse to first unplug the leads.
A published RCT (randomized controlled trial) by Wainwright et al15 also demonstrates the geko’s post-operative oedema control credentials. The study compared the effect of the geko™ device to TED Stockings (standard of 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 currently being used post-discharge for knee replacement patients. 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 trained to self-apply the device and are provided with treatment packs for nine days of geko™ device use to maintain their oedema prevention. The data, when published, will speak perfectly to the recovery from surgery, considered the next frontier in US.
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 Sener16, 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 the 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.
These published studies and an ongoing program of research 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. The easy-to-use and clinically proven geko™ device 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.
Sue Davenport – VP Marketing Communications
5th October 2021