An Opening in the Abdomen

An Opening in the Market:

Hernia Tensiometer

GROUP 2:Martha Ingram

Megan JohnstonChelsea Samson

What Is a Hernia?

Laparoscopic

Open

“Tension-Free” Repair

Method

MAKING THE CASE FOR HERNIA RESEARCHBK Poulose, MD, MPH; J Shelton, MD; S Phillips, MSPH; DE Moore, MD, MPH; W Nealon, MD; D Penson, MD, MPH; MD Holzman, MD, MPH

Background:

$ Inpatient discharges from 2001-2006 Healthcare Cost and Utilization Project

$ Outpatient estimates from 2006 CDC National Survey of Ambulatory Surgery

$ Total number of ventral hernia repair procedures performed in the U.S.

$ Extrapolated operation dollars from 2006 to 2009 monies using Consumer Price Index

Methods:

“Currently, there is a lack of standardization in ventral hernia repair procedures, with widespread variation in delivery”

Lack of standard delivery Increased complications post-surgery increased cost

Results

IN 2006: 154,278 inpatient + 193,543 outpatient =

348,000 operations

1 inpatient operation = $15,374 1 outpatient operation = $3,745

Total Expenditure in Procedures =$3.1

billion on VHR

Mean Cost of Ventral Hernia Repair

Procedures over Time

*adapted from BK Poulose, J Shelton, DE Moore, W Nealon, D Penson, M Holzman, Making the Case for Hernia Research. 2011.

Year

Cost

per

Dis

ch

arg

e

*adapted from BK Poulose, J Shelton, DE Moore, W Nealon, D Penson, M Holzman, Making the Case for Hernia Research. 2011.

Mean Frequency of Ventral Hernia Repair Operations over

Time

Year

Nu

mb

er

of

Dis

ch

arg

es

IT IS ESTIMATED THAT A

1% REDUCTION IN VHR OPERATIONS COULD SAVE

$31 MILLION IN HEALTHCARE COSTS IN

THE U.S. PER YEARThe application of an intra-operative tension-measuring

device could increase understanding of and prevent

hernia recurrence, significantly decreasing costs

•Measure tension resisting closure at the suture line

after:- dissection of the injury area

- separating fascia from muscle-placing the mesh

•Isolate abdominal tissue•Bring edges together

•Read tension at center of hernia

User Feedback: Get a force (Newtons) and want to know if failure will

occur…

Tension (N)

Probability of Recurrence

100 %90 %80 %70 %60 %50 %40 %30 %20 %10 %0 %

User Response:

Relaxing Incisions

Mesh Placeme

nt

Suture Closed

Clamp both hernia edges between metal

plates

Large, sharp serrations hold tissue in place

Lash force sensors across

opening

Static arm

Mobile arm

Digital display

Gear to wind hernia edges

together

Force Sensor

Indentation Testing

Calibration1. Initial calibration

– Known weights (0-5 kg) applied

– Measure voltage output in Labview

– Convert to force

2. Tare– Zero weight zero force

3. Pre-operative testing– Surgeons will calibrate with

weights every 5-10 uses to confirm precise results (calibration curve is still relevant)

Timeline – Near Future

• Attach sensors and test with weights –

today• Test on porcine

model – 4th week of Feb

• Modify design – early March