bme lab report

Kishan PatelEngineering Exploration—Section 1 BME Lab Report RUID: 158—00—6143

Introduction:

Bioabsorbable Therapeutics, a company founded to develop the next generation of devices to

treat vascular diseases, has developed a new bioabsorbable stent. A bioabsorbable stent is designed from

materials that can dissolve or be absorbed in the body; in particular, Bioabsorbable Therapeutics’ new

stent is coated with a polymer which will release PolyAspirin, as it degrades over the course of six to

twelve months. PolyAspirin is a drug developed by Dr. Kathryn Uhrich at Rutgers University.

PolyAspirin was originally designed for biodegradable sutures; however, recently it has become

prominent in the making of bioabsorbable stents. This new stent aims to control the post-angioplasty

inflammation effects. An angioplasty is a surgical process or repairing or unblocking of a blood vessel.

The stents will be placed inside blood vessels for several months, thus, they must be able to withstand a

range of blood pressures, ranging from sedentary activities to stress-intensive physical exercises. The

company must be assured that the stents are functioning appropriately. The goals of this experiment were

to determine if the stents were functional, to determine the stress the stents can withstand, and to

determine the stress the stents can place on the surrounding blood vessels. Such scrutiny of the stents was

necessary because if the stents exert too little or too much stress on the surrounding blood vessels the

consequences can be fatal for the patients.

Methodology:

A group of 32 patients who had recently gone an angioplasty procedure was taken, and all

were fitted with the new bioabsorbable stent.

The group of 32 patients was further broken into 4 experimental groups: the Control group,

the Relaxation group, the Physical Activity group, and the Caffeine group.

Each experimental group was assigned an activity, upon completion of which the blood

pressure of the patients was measured and recorded.


o Each patient had his/her blood pressure taken three times—the average of which was

used in the analysis of this experiment.

o The Control group was assigned no activity other than measuring the BP of the

patients three times. This would establish the precision of the BP machines, and take

into account other variations which may occur.

o The Relaxation group lied down for 2 minutes prior measuring the BP.

o The Physical Activity group performed jumping jacks for 60 seconds before

measuring the BP. (Waited 3 minutes before repeating)

o The Caffeine group drank a can of soda prior to measuring the BP. (Waited 5 minutes

before repeating)

Results: (These results exclude the data of patients who died due to either hypo- or hyper tension crisis.)Graph 1 shows the average Mean Atrial Pressure in units Pascal for each individual group of patients.

Table 1 shows the average PMAP and Hoop Stress values, along with the range of PMAP and Hoop Stress values.

Average PMAP 11980.44444 PascalLowest PMAP 9911.111111 PascalHighest PMAP 14325.92593 Pascal

Average PMAP Hoop Stress 143244.4444 PascalLowest PMAP Hoop Stress 118502.4155 PascalHighest PMAP Hoop Stress 171288.2448 Pascal

Control Caffeine Relaxation Exercise10000

10500

11000

11500

12000

12500

13000

13500

11503.7037037037 11217.283950617

3

12055.0264550265

13133.3333333333

Graph 1

Group

Aver

age

PMAP

(Pas

cals)


Table 1Conclusion:

The goal of this experiment was to determine if the stents were functioning properly, and

whether they would be able to withstand the varying range of stresses exerted upon blood vessels.

According to the data collected, it can be inferred the bioabsorbable stents do function properly. The

stents exert a hoop stress of values between 118502.4155 Pascal and 171288.2448 Pascal. The group

doing the exercise experienced the highest PMAP, while the caffeine group experienced the lowest

PMAP. However, it is important to note that the results only take into account the BP of alive patients.

There were 7 fatalities, 4 due to hypertension crisis and 3 due to hypotension. This indicates that the

stents can burst open; resulting in an intense drop in BP resulting in hypotension, or the stents can

succumb to the pressure exerted by the blood vessels, resulting in an intense rise in BP resulting in

hypertension. In a project such as this bioabsorbable stent, engineers focus on the mechanics of the

project, as well as the development of the stent. Engineers test the physical aspects of the stent, such as

the stress the stent would exert on the blood vessels, or the stress the blood vessels would exert on the

stent. Taking these tests into consideration, engineers develop the stent with polymers developed by

the scientists. The engineers work with doctors to ensure that the physical aspects of the stents aren’t

injurious to health of the patients. The engineers also help the sales process by helping with price

configuration. Since they have been involved in the stents’ production, they have a better understanding

of the production costs of the stent. Engineers play a critical role in the development of such a project.

Also, according to the data collected, Bioabsorbable Therapeutics’ bioabsorbable stent functions

properly.

bme lab report

Documents