Clinica's MedTech Ventures: ProDural
This article was originally published in Clinica
Specialty area(s): Safe epidural placement
Based in: Cork, Ireland
Founded in: 2014
No. of employees: 5
Total investment received to date: No equity investment yet. Activities to date have been supported through a Cleveland Clinic/Enterprise Ireland clinical innovation award and funding from University College Cork
Investors: No investors yet
Physicians are a notoriously conservative lot. While there are the early adopters who are always keen to try out innovative technologies, most prefer to stick with tried and tested methods.
This rings true, according to Irish start-up ProDural, among anesthesiologists when it comes to administering analgesics via an epidural. “The current method for finding the epidural space [in which the drug would then be deposited] is known as the loss of resistance, or LOR, technique,” explains Conor O’Shea, chief technology officer of the University College Cork spin-out. “This LOR approach is favored by over 90% of anesthesiologists.”
The technique, however, is very challenging – a 2011 study of epidural practices in Nordic countries found that there was a 1 in 5 failure rate for the first 50 epidurals administered by trainee anesthesiologists and it may take up to 75 attempts before proficiency is reached.
The difficulty lies in knowing for sure when the needle has reached the epidural space. The anesthesiologist has to rely on tactile feedback and be able to sense a sudden pressure drop at the needle tip as they advance the syringe plunger, says Mr O’Shea. “The second you reach that space, the pressure would immediately fade and this change can be quite subtle. If you miss the epidural space, it can result in a number of complications.”
One complication is accidental dural puncture (ADP). This occurs when the needle goes beyond the epidural space and into the dura, one of the three layers of membrane that surround the spinal cord and brain and contain the cerebrospinal fluid. With the dura punctured by the needle, the cerebrospinal fluid could leak out, causing a change in pressure in the rest of fluid and resulting in a severe headache known as postdural puncture headache. “ADPs have an average rate of incidence of 2-4% of all epidurals in the US, which might be relatively low but the incidence of postdural puncture headaches following an ADP is 80-86%,” says Mr O’Shea.
These headaches can stay for weeks and the way to rectify this is with a “blood patch”. This entails taking blood from the patient and injecting it in the back, near the hole in the dura. A clot forms and acts as a plug. “This is another invasive procedure and you’d need to keep the patient in the hospital, which means extra hospital days.” Data from the US show that in 2010, ADP was the cause of extending patients’ hospital stay by an estimated 73,915 days, or 202 years. With each day in hospital costing around $1,500, this means US healthcare payers fork out $111m each year due to extended stays related to ADP.
Another problem with epidurals is the rate of false positives, when the anesthesiologist thinks the needle has reached the epidural space before it actually does and the analgesic is deposited wrongly into the tissue. “False positives are more common in obese patients who have layers of fatty tissue. There are varying densities as the needle moves towards the epidural space and directly prior to arriving at the epidural space there is dense ligament so you’ll see a spike in pressure. The problem is that you might feel a little give and mistakenly think you have reached the epidural space so you release the drug into the tissue and there is no pain relief. You see that in expecting mothers, half of them in the US are overweight or obese, and do not feel the pain relief and they go in with a second epidural by which time it might be too late,” explains Mr O’Shea.
To help overcome the challenge of administering epidurals successfully, ProDural has developed a syringe that has a visual indicator to help confirm when the needle has reached the epidural space. This indicator comes in the form of an expandable diaphragm, made from a very brightly – “almost luminous” – colored elastomeric material, that sits on top of the barrel (see Figure 1). As the needle is advanced through the tissue, there is increasing pressure in the barrel which causes the diaphragm to expand. Once the needle reaches the epidural space and there is a drop in pressure, the diaphragm “pops” and collapses immediately, indicating to the clinician that the needle has been correctly placed.
Mr O’Shea acknowledges that there are a number of competing technologies on the market that also claim to help make epidural administration easier.
Among ProDural’s potential rivals are the Episure AutoDetect syringe and the EpiDrum. The Episure has an internal compression spring which applies a force on the plunger. This plunger then automatically depresses when it reaches the epidural space. The EpiDrum comprises a non-return internal valve and is “charged” or primed prior to application and automatically collapses once the epidural space has been reached. With these two products, because they involve automatic triggers, anesthesiologists lose the tactile sensation that they get and are used to with a conventional LOR syringe, thus creating uncertainty of correct needle placement, believes Mr O’Shea.
The ProDural syringe maintains the popular LOR technique with the haptic feedback, while providing a clear visual indication with its deflating diaphragm,” he tells Clinica. “We’ve completed a feasibility and pre-clinical study and it seems to improve reaction time of anesthesiologists as it makes it more apparent when the pressure drops,” says the CTO. This then prevents excessive needle advancement and reduces the risk of accidental dural puncture. “ProDural also reduces the risk of false positive readings in obese patients as the clinician may vary the applied pressure to determine when the epidural space has been reached. The contrasting bright surface of the diaphragm ensures clear visibility even in a dimly lit maternity ward. It may also reduce the steep learning curve because the bulging diaphragm allows teaching clinicians to visually determine correct placement by their trainee doctors,” he continues.
Another advantage to ProDural’s syringe is that it comes at a minimal increase to the cost of existing technology. “There are more expensive technologies that use ultrasound and fiber optics to help with the epidural administration but these have struggled to gain traction. One of the main reasons is that epidural administration is a very cheap procedure. It might cost around $18 for a complete kit with the catheter, syringe and needle, so hospital purchasing bodies don’t want to bring in a technology with sensors built in that might cost $2,000 – which is why we stuck with the tried and trusted LOR technique with a visual indicator.”
The regulatory barriers for ProDural’s syringe are not significant: the product is considered a class I device in Europe, so it would not require any human data in order to be CE-marked. In the US, it would be a class II device and the company would go down the 510(k) clearance route there. “We’d like to add a bit more value to device by getting approval before moving forward and seeking funding,” says Mr O’Shea.
Until now, ProDural has supported its product development activities using internal university funding and a clinical innovation award it won from The Cleveland Clinic and Enterprise Ireland. When it does go out to look for investors, the start-up would be seeking to raise around $1m – a task that may not be difficult, considering it has already attracted interest within industry and its co-founder, P�draig Cantillon-Murphy, has a track-record in device innovation from MIT and Harvard Medical School. In April, ProDural was a finalist in RCT Ventures’ MedTech Idol competition, held during the IN3 partnering conference in Dublin, Ireland. It was a recent prize-winner at the Massachusetts Medical Device Development new venture competition which was supported by Nutter McClennen & Fish and Smith & Nephew.
More importantly, ProDural seems to be already getting the thumbs up from the clinical community, according to Mr O’Shea. “We went to The Cleveland Clinic last November and got very positive feedback from KOLs there. We tick all the boxes in terms of addressing their concerns.”
Conor O’Shea, chief technology officer. Email: firstname.lastname@example.org
ProDural c/o University College Cork, College Road, Cork, Ireland.