Running head: TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
Two Group Comparison: Usability and Satisfaction of Sequential Compression Devices
Lynn A. Henderson
University of South Florida
1
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
2
Abstract
Mechanical compression devices are recommended as VTE prophylaxis either as a dual
modality prophylaxis with a pharmacological agent or to be used alone in patients with
significant bleeding risks. However, although the use of a mechanical compression device is
shown to decrease the incidence of VTE whether used alone or with a chemical agent, its
effectiveness is limited by poor compliance and improper use (Pagella et al., 2007; Westrich &
Sculco, 1996; Ritsema et al., 2013). The objective of this outcome project is to compare the
usability (rate of adherence) and patient satisfaction of two equally effective sequential
compression devices (SCD) used by post-operative total knee arthroplasty patients. Rosenstock’s
health belief model (HBM) is focused on patient compliance and has provided a theoretical
framework showing how patient satisfaction with a treatment influences patient compliance
(Polit & Beck, 2012). This outcome project has utilized a two group comparison with quasiexperimental design to determine better usability (adherence rate of usage) and satisfaction
between two products, SCD product “A” and SCD product “B”.
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
3
Introduction to the Problem
Preventing venous thrombotic events is a standard of care for healthcare organizations
and facilities throughout the US. There is an estimated 350,000 to 600,000 patients who develop
venous thromboembolism (VTE) annually and the patient undergoing total joint surgery falls
into a very high risk category for VTE (The US Department of Health Services, 2012). In these
patients, the risk for deep vein thrombosis (DVT) is as great as 54% if they are not given any
form of VTE prophylaxis. VTE prophylaxis, whether chemical and/or mechanical, reduce the
risk for DVT by 70% or greater (Agency for Healthcare and Research Quality, 2011).
Mechanical prophylaxis effectiveness is comparable to pharmacological agents only if the
mechanical device is used correctly. The disadvantage to SCD use is the decrease in its
efficiency due to poor compliance or ineffective use. There is a direct correlation with the
amount of time a SCD is worn and its effectiveness (Pagella et al., 2007). For patients
developing DVT, compression device compliance was reported at 56% versus 80% for patients
that did not develop DVT (Westrich & Sculco, 1996). The objective of this outcome project is to
compare usability (adherence rate of usage) and patient satisfaction of two equally effective
sequential compression devices (SCD) used by post-operative total knee arthroplasty patients.
Literature Search
The clinical question for this project is “does “A” SCD product have better usability
(adherence rate of usage) and satisfaction than “B” SCD product?”
The patient, intervention, comparison, outcome (PICOT) criteria used to formulate the
clinical question is as follows: P: post-surgical total knee arthroplasty patients; I: SCD product
“A”; C: SCD product “B”; O: usability (adherence of usage) and satisfaction; T: post-op period.
A literature search was performed in CINAHL, Pub Med, and Cochrane Library databases using
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
4
the key terms “VTE, prevention, surgery, sequential compression device (SCD), pneumatic
compression device (PCD), mechanical compression device (MCD), and compliance”.
Literature Review
VTE Prophylaxis Clinical Guidelines
The American College of Chest Physicians (ACCP) and the American Academy of
Orthopaedic Surgeons (AAOS) have established clinical guidelines for the prevention of VTE in
the orthopedic surgery patient. They both recommend the use of an intermittent pneumatic
compression device (IPCD) in addition to a pharmacologic agent in VTE prevention for
hospitalized patients. Mechanical thrombophylaxis is recommended for patients with a high risk
of bleeding versus no prophylaxis at all (American College of Chest Physicians [ACCP], 2012;
American Academy of Orthopaedic Surgeons [AAOS], 2011).
Multimodal VTE Prophylaxis
A systematic review including eleven studies; six of them randomized controlled trials
(RCT) that included 7431 patients compared using pharmacological prophylaxis alone or
combined pharmacologic and mechanical modalities to reduce the incidence of VTE. The six
RCT’s showed the incidence of PE and DVT among the SCD + anticoagulant versus SCD
groups as well as the incidence of PE and DVT among the SCD + anticoagulant versus
anticoagulant groups. The studies included in this review included a wide range of patient
groups undergoing surgery, especially orthopedic surgeries. Compared with using SCD’s alone,
the use of multimodal prophylaxis reduced the occurrence of both PE, (from 3% to 1%; OR 0.39,
95% CI 0.25 to 0.63) and DVT (from 4% to 1%; OR 0.43, 95% CI 0.24 to 0.76). When
comparing pharmacological prophylaxis alone, combined modality use significantly reduced the
prevalence of DVT (from 4.21% to 0.65%; OR 0.16, 95% CI 0.07 to 0.34) (Kakkos et al., 2008).
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
5
A randomized double blind placebo-controlled trial of 1,309 patients was conducted to
examine the effectiveness of using pharmacological agent fondaparinux combined with
intermittent pneumatic compression (IPC) versus the use of IPC alone in the prevention of VTE.
Among these patients, the VTE rate was 1.7% in the fondaparinux group, as compared to 5.3%
in the placebo group (Odds Ratio Reduction 69.8%, 95% Confidence Interval 27.9-87.3;
P=0.004). The results indicated that fondaparinux reduced the VTE rate by 69.8% as compared
to intermittent pneumatic compression alone. Although the use of intermittent pneumatic
compression can be effective at decreasing the risk for VTE, these studies show that SCD use
alone is not as effective as the simultaneous use with a pharmacologic agent (Turpie et al., 2007).
Compression Device Compliance and Effectiveness
A randomized study of 122 patients who underwent total knee arthroplasty was
conducted assessing pneumatic plantar compression and aspirin vs. aspirin alone for deep venous
thrombosis (DVT) prophylaxis. The prevalence of deep venous thrombosis was 27 % in the
pneumatic plantar compression group and 59% in the patients managed with aspirin alone (p <
0.001). To measure patient compliance, an internal timer reporting the amount of time it was
used showed a relationship between DVT development and the total length of pneumatic
compression device treatment. Patients who did not develop a DVT used the device for a mean
of 96 ± 23.4 hours postoperatively (19.2 ± 5.1 hours a day) and patients who developed a DVT
used it for a mean of 67 ± 21.1 hour s(13.4 ± 4.3 hours a day) (p < 0.001). The study supports the
use of mechanical compression for prophylaxis against DVT but also shows a direct relationship
between compliance with device use and its effectiveness in reducing deep venous thrombosis
(Westrich & Sculco, 1996).
Additionally, a quantitative descriptive study designed to evaluate patient compliance and
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
6
its direct correlation with patients’ comfort and satisfaction with the mechanical compression
device (MCD) used a randomized survey of 70 post-surgical patients wearing either one of two
equally effective MCD’s, product X or Y, to show how comfort and compliance with a device
directly correlates with compliance of its use. Patients were more satisfied with product Y over
product X and thus were more compliant with its use. The amount of time product Y was worn
was greater than product X, respectively 85% vs. 81% (Pagella et al., 2007).
Summary and Gaps in Literature
Evidence from studies indicates that the use of mechanical compression devices along
with pharmacological agents significantly reduces the risk for developing a VTE following
orthopedic surgery. Although mechanical devices are often used in the post-surgical patient,
studies show the effectiveness at DVT prevention when using the compression device alone is
not significant enough to use over adjunct therapy (Kakkos et al., 2008; Turpie et al., 2007).
Studies show that poor compliance with the use of a sequential compression device limits its
effectiveness at preventing DVT’s. Studies have been conducted to evaluate SCD compliance by
utilizing a variety of methods to measure patient satisfaction, nurse satisfaction, usage time
recorded by internal timer or by patient and nurse perception of usage times (Pagella et al., 2007;
Westrich & Sculco, 1996; Ritsema et al., 2013).
Theory: Health Belief Model
The disadvantage to SCD use is the decrease in its efficiency due to poor compliance or
ineffective use. Rosenstock’s health belief model (HBM) is focused on patient compliance and
preventive practices. The major components of the HBM include perceived benefits and costs,
motivation, and enabling or modifying factors. During this project, perceived benefits would be
the belief that a treatment such as the SCD will prevent DVT’s while perceived barriers would be
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
7
SCD complexity or discomfort. Patient satisfaction is an identified modifying factor that affects
a patient’s motivation to comply with treatment (Polit & Beck, 2012). This theoretical concept is
the basis for this outcome project.
Methodology
Design/ Method
The proposed project would utilize a two group comparison quasi-experimental design to
assess the adherence rate of usage and satisfaction of two pneumatic compression devices:
currently used SCD product “A” and comparable SCD product “B”.
Setting/ Sample
This prospective study would be conducted in an inpatient hospital setting. A total of 80
patients undergoing elective total knee arthroplasty would be randomized using simple random
sampling into two groups A or B. Each group will have 40 participants and the study would take
place over a 3 month study period.
Inclusion and Exclusion Criteria
All patients would have undergone elective total knee arthroplasty, be admitted into the
hospital for at least three days post operatively, and have a physician order for continuous SCD
use. Exclusion criteria would include existing or suspected deep vein thrombosis (DVT),
cognitive impairment, or any contraindication to SCD use.
Procedures
Approval would be obtained from hospital administration, director of surgery, and the
orthopedic surgeons of the possible sample population. Patients would be selected for
enrollment based on criteria, contacted for participation and consents obtained. Participants
would be assigned to a group based on a sampling frame and random assignment of numbers into
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
8
groups A or B. Participants would be blinded to the study objective until post-op day three when
they opened their study packet with questionnaire and instructions. Nurses would need
education on data collection and protocol which would include instruction to measure usage time
from internal timer device every shift and to keep the same patient assignment throughout patient
stay. They would answer the nurse questionnaire on post-op day three along with the patient.
Nurses would be notified on day of surgery as to which SCD product to place on patient preoperatively.
Dependent variable
The dependent variable would be usability and satisfaction of product A and B. The
outcome would be measured by answers to a 10 question patient questionnaire and a 7 question
nurse questionnaire made up of previously validated questions using a 5-level Likert Scale:
1. Strongly disagree
2. Disagree
3. Neither agree nor disagree
4. Agree
5. Strongly agree
(Pagella et al., 2007; Ritsema et al., 2013)
See Appendix 1 for patient questionnaire and Appendix 2 for nurse questionnaire.
Independent variable
The independent variable is either SCD product “A” or SCD product “B”. Product “A” is
a currently used SCD device with a sleeve made of a heavy plastic material (the Kendall
compression device), and Product “B” uses a sleeve made of a lighter weight, breathable material
(Huntleigh Flowtron compression device).
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
Data Collection
Group demographic variables that include age, gender, length of stay, and type of VTE
prophylaxis would be gathered from the patient electronic health record (EHR). Clinical
variables usability and satisfaction of product A and B would be measured by answers to a 10
question patient questionnaire and a 7 question nurse questionnaire using a 5-level Likert Scale.
Data Analysis
The Likert-level data from the patient and nurse questionnaires as well as the perceived
and documented average percentages of usage times of group A and B would be compared by
the use of t test analysis. Nonparametric tests and chi-square analysis would compare
demographic information of age, gender, and length of stay between group A and group B to
examine these variables and their correlation with the usability and satisfaction rate of the two
SCD products.
Dissemination Plan
The evidence based EB outcome project should identify a problem with the currently
used SCD of the hospital and measure its usability along with patient satisfaction compared to a
new, more comfortable product that should demonstrate superior adherence of usage and patient
satisfaction. Lewin’s model for change will be implemented to incur changing from the current
SCD to the more effective one. Within the group dynamics element, support must be obtained
from hospital board of directors, president, chief officers, and directors by giving them
background information and an outlined plan of action. Carrying out the third element of action
research requires this outcome project be conducted in the hospital evaluating the problem with
the currently used SCD and offering evidenced based data to support the proposed product
change. The four elements are integrated within the three stages : (1) unfreezing the current
9
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
10
practice of using a particular SCD, (2) moving by introducing and explaining the benefits of
using a better product, and (3) refreezing by initiating the change to another SCD (Suc,
Prokosch, & Ganslandt, 2009). Applying Lewin’s change model to this evidence based (EB)
outcome project would allow for successful organizational change leading to better clinical
practice.
References
American Academy of Orthopaedic Surgeons. (2011). Guideline on preventing venous
thromboembolic disease in patients undergoing elective hip and knee arthroplasty.
Retrieved from http://www.aaos.org/research/guidelines/VTE/VTE_guideline.asp
Agency for Healthcare Research and Quality. (2011). Making healthcare safer, a critical analysis
of patient safety practices. Retrieved from
http://www.ahrq.gov/clinic/ptsafety/chap31b.htm
Falck-Ytter, Y., Francis, C., Johanson, N., Curley, C., Dahl, O., Schulman, S., & ... Colwell, C.
(2012). Prevention of VTE in orthopedic surgery patients: Antithrombotic therapy and
prevention of thrombosis, 9th ed: American college of chest physicians evidence-based
clinical practice guidelines. Chest, 141(2 Suppl), e278S-325s. Retrieved from
http://web.ebscohost.com/ehost/detail?vid=3&hid=13&sid=e2c7c12d-4cb7-4ac1-8119d38ce05f1e7b%40sessionmgr13&bdata=JnNpdGU9ZWhvc3QtbGl2ZSZzY29wZT1zaX
Rl#db=rzh&AN=2011460988
Hardwick, M., Pulido, P., & W. (2011). A mobile compression device compared with
low-molecular-weight heparin for prevention of venous thromboembolism in total hip
arthroplasty. Orthopaedic Nursing, 30(5), 312-316.
doi:10.1097/NOR.0b013e31822c5c28
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
11
Kakkos, S., Caprini, J., Geroulakos, G., Nicolaides, A., Stansby, G., Reddy, D. (2008).
Combined intermittent pneumatic leg compression and pharmacological prophylaxis for
prevention of venous thromboembolism in high-risk patients. Cochrane Database of
Systematic Reviews 2008, Issue 4. Art. No.: CD005258. DOI:
10.1002/14651858.CD005258.pub2
Pagella, P., Cipolle, M., Sacco, E., Matula, P., Karoly, E., & Bokovoy, J. (2007). A randomized
trial to evaluate compliance in terms of patient comfort and satisfaction of two pneumatic
compression devices. Orthopaedic Nursing, 26(3), 169-174. Retrieved from
http://ehis.ebscohost.com.ezproxy.hsc.usf.edu/ehost/resultsadvanced?sid=b3cc5969-7f5549c6-98ac
Polit, D. & Beck, C.T. (2012). Nursing research: Generating and assessing evidence for nursing
practice (9th ed). Philadelphia: J. B. Lippincott.
Ritsema, D., Watson, J., Stiteler, A., Nguyen, M. (2013). Sequential compression devices in
postoperative urologic patients: an observational trial and survey study on the influence
of patient and hospital factors on compliance. BMC Urology, 13(20), 1-7. Retrieved
from http://www.biomedcentral.com/1471-2490/13/20.
Suc, J., Prokosch, H., Ganslandt, T. (2009). Applicability of Lewin’s change management model
in a hospital setting. Methods Inf Med, 48(5):419-28. doi: 10.3414/ME9235
Turpie, A., Bauer, K., Caprini, J., Comp, P., Gent, M., Muntz, J., Apollo Investigators.
(2007). Fondaparinux combined with intermittent pneumatic compression vs. intermittent
pneumatic compression alone for prevention of venous thromboembolism after
abdominal surgery: a randomized, double-blind comparison. Journal of Thrombosis and
Haemostasis, 5(9):1854-61. Retrieved from
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
http://www.ncbi.nlm.nih.gov/pubmed/17723125
Westrich, G., Sculco, T. (1996). Prophylaxis against deep venous thrombosis after total knee
arthroplasty. Pneumatic plantar compression and aspirin compared with aspirin alone.
Journal of Bone and Joint Surgery American, 78(6), 826-834. Retrieved from
http://jbjs.org/article.aspx?volume=78&page=826
12
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
Appendix I- Patient Questionnaire
Patient Questions
1. 1. Device comfortable
2. 2. Device interfered with movement
3. 3. Device was loud
4. 4. Device kept patient awake
5. 5. Device was hot
6. 6. Device made leg/legs sweat
7. 7. Used device in bed
8. 8. Used device in chair
9. 9. Would not use again
10. Percent of time device used in last 24 hours
Appendix 2: Nurse Questionnaire
Nurse Questions
1. 1. Easy to size
2. 2. Easy to apply
3. 3. Comfortable for patient
4. 4. Simple connections
5. 5. Pressure setting is appropriate
6. 6. In a typical 24-hour period, patients wear their
pneumatic compression device what percent of the
time
7. 7. In a 24-hour period, what percentage of time did
patient wear compression device according to internal
timing device?
13
TWO GROUP COMPARISON OF SEQUENTIAL COMPRESSION DEVICES
14