Welcome to Project Healthy Hearts

People living in different parts of East Texas face different health problems and factors that contribute to these poor health outcomes. We will meet with participants five times during the research project to evaluate social, economic, and physical aspects of health. The data from this project will be used to evaluate the status of health in our community as well as spur conversations about what factors we need to explore further. 

To begin this journey, the project will search out at least 50 participants. Participants will be between 18-80 years of age and free of known cardiovascular disease or digestive disorders. 

Participants will be given an overall health evaluation at the university health clinic. In addition, these participants will be screened for any conditions that may skew the data we intend to collect. If selected for the study, the participant will undergo initial testing to create baseline cardiac output and digestive function results. For one year, the participants will spend one hour a day in a passive leg elevation position. Every three months, the participant will be evaluated for overall health status, cardiac output, and digestive function.

You can learn more about the project and participation by filling out the inquiry form below or reaching out via email at pleproject@etbu.edu.

Trendelenburg positioning was first used in medical intervention by a Scottish doctor in 1890 as a way to gain access to pelvic organs. During World War 1, Trendelenburg was used by a physiologist Walter Cannon to treat shock. Dr. Cannon asserted that by lifting the legs higher than the heart, you could increase cardiac output and improve blood flow to vital organs. From this point forward, Trendelenburg became a best practice in critical care to address severe hypotension. (Shammas and Clark, 2007).

However, a series of research conducted in the late 1970s and 1980s questioned the efficiency of Trendelenburg and evaluated potential adverse effects. Sibbald et.al found in 1979 that Trendelenburg did not consistently improve hemodynamic effects in hypotensive patients. However, in 1988, Gentili et. al found that Trendelenburg improved cardiac function by increasing cardiac output, mean arterial pressure, and central venous pressure. But Gentili also questioned the safety of Trendelenburg when a patient was not in a critical state due to possible increased thoracic and cranial pressure. Thoracic pressure was greater in those with pulmonary co-morbidities and those of large weight mass (Gentili et. al. 1988).
 
Further research was conducted in the mid-nineties that looked at Modified Trendelenburg, which reduced intracranial pressure by keeping the head at an even elevation with the torso but still having the legs elevated. Ostrow et.al. found that while cranial pressure was reduced the effects on mean arterial pressure, cardiac output, and systemic vascular resistance were of no significance. In addition, Terrai et.al. found in 1995, that a 10 degree modified Trendelenburg position increased left ventricular end-diastolic volume, stroke volume, and cardiac output, but the results dissipated after 10 minutes.
 
As research into Trendelenburg positions continued, Passive Leg Elevation (PLE) was introduced. Passive Leg Elevation is a technique used in a sitting position with a slight 30-degree leg elevation. PLE is commonly used by Coronary Artery Bypass Graft (CABG) patients. Research found that PLE worsened conditions of patients with reduced right ventricular end-diastolic volume. But Biais et al. did find that stroke volume increased with PLE.
 
Current research suggests that PLE and modified Trendelenburg positioning can temporarily increase cardiac output, stroke volume, and ejection fractions, but these changes tend to dissipate after 10 minutes of repositioning. What is unknown is whether PLE or modified Trendelenburg has long term effects on cardiac muscle health or whether cardiac output, stroke volume, or ejection fractions are affected by continuous patterned use of the positions.

In addition, literature also indicates that blood flow not only is increased to the pericardial cavity during PLE and Modified Trendelenburg and the abdominopelvic cavity. Intestinal blood flow accounts for 15% of cardiac output. 65% of this intestinal blood flow is directed to the mucosal layer of the small intestine. The mucosal layer of the small intestine is responsible for the absorption of nutrients during the digestion process. Blood flow to the small intestine is supplied via the Superior Mesenteric Artery (SMA). Little literature exists on the effect of gut blood flow on digestion progression, nutrient absorption, and intestinal angina. The Doppler of the ultrasound used for echocardiography could also be used to track SMA blood flow and rate of progression in the gut.

• Biais M, Vidil L, Sarrabay P, Cottenceau V, Revel P, Sztark F: Changes in stroke volume induced by passive leg raising in spontaneously breathing patients: comparison between echocardiography and Vigileo/FloTrac device. Crit Care 2009, 13: R195. 10.1186/cc8195
• Geerts BF, van den Bergh L, Stijnen T, Aarts LP, Jansen JR. Comprehensive review: is it better to use the Trendelenburg position or passive leg raising for the initial treatment of hypovolemia?. J Clin Anesth. 2012;24(8):668-674. doi:10.1016/j.jclinane.2012.06.003
• Bertolissi M, Da Broi U, Soldano F, Bassi F. Influence of passive leg elevation on the right ventricular function in anaesthetized coronary patients. Critical Care (London, England). 2003 Apr;7(2):164-170. DOI: 10.1186/cc1882.
• CL Ostrow, E Hupp, D Topjian; The effect of Trendelenburg and modified trendelenburg positions on cardiac output, blood pressure, and oxygenation: a preliminary study. Am J Crit Care 1 September 1994; 3 (5): 382–386. doi: https://doi.org/10.4037/ajcc1994.3.5.382
• Gentili DR, Benjamin E, Berger SR, Iberti TJ. Cardiopulmonary effects of the head-down tilt position in elderly postoperative patients: a prospective study. South Med J.
• 1988;81(10):1258-1260. doi:10.1097/00007611-198810000-00014
• Fahy, B.G., Barnas, G.M., Nagle, S.E., Flowers, J.L., Njoku, M.J. & Agarwal, M. (1996). Effects of Trendelenburg and reverse Trendelenburg postures on lung and chest wall mechanics. Journal of Clinical Anesthesia, 8(3), 236-244.
• Reuter, D.A., Felbinger, T.W., Schmidt, C., Moerstedt, K., Kliger, E., Lamm, P. & Goetz, A.E. (2003). Trendelenburg positioning after cardiac surgery: effects on intrathoracic blood volume index and cardiac performance. European Journal of Anesthesiology, 20(1), 17-20.
• Shammas, A. & Clark, A. (2007). Legal and Ethical: Trendelenburg positioning to treat acute hypotension: Helpful or harmful? Clinical Nurse Specialist: The Journal for Advanced Nursing Practice, 21(4), 181-187.

Current County Health rankings for both Texas and East Texas demonstrate poor health outcomes and behaviors related to heart, lung, and digestive health. East Texas ranks the lowest in the state for these factors, and the following report identifies factors that go beyond healthcare. The next step is to explore these factors and dive deeper into what direct causes are resulting in these unhealthy outcomes. Sign up to the project listserv to stay in the loop on current health issues within the county. Email pleproject@etbu.edu. If you are already a participant you will be automatically enrolled in our mailing list.

Health County Rankings

Project Coordinator:
Dr. Shannon Cox-Kelley scoxkelley@etbu.edu

Research Assistant:
Makenzie Pinkston

Project email: pleproject@etbu.edu

Even if you don’t enroll in the research study, you can still get involved by participating in a health lecture series and by volunteering at data collection events. Reach out to the project team to learn more.

1. What kind of tests will be conducted?

In order to evaluate heart function, two methods are typically used, cardiac biomarkers and echocardiography. Cardiac biomarkers use a blood test to evaluate enzymes in the bloodstream. The markers called troponin, creatine kinase, and myoglobin can indicate various heart conditions, including cardiac muscle function, which can be impacted by blood flow. Echocardiography uses ultrasound to provide an image of the heart structures. Heart structures that can be evaluated include the chambers, valves, and vessels. With a Doppler function, echocardiography can also be used to measure blood flow and volume, providing a stroke volume and ejection fraction estimate.

To evaluate cardiac functions, participants will be given a transthoracic cardiac echo with Doppler. Due to the invasiveness, cardiac biomarkers will not be evaluated at this time. However, follow up future research may include this measurement. To evaluate digestive functions, participants will consume a 600 kcal milkshake, and a transcutaneous doppler will be administered, measuring SMA flow and duodenal small intestine progression.

2. What criteria will be used for inclusion and exclusion of participants?

Participants can be of any gender or race and must be between 18 and 80 years of age. East Texas Baptist University employees, students, and community members will all be invited to participate. 

Participants under 18 and over 80 will be excluded due to age-related heart and bowel functional differences. In addition, participants with known heart and digestive disease/disorders will also be excluded. Based upon the visit one medical health history, other conditions may also exclude participants, including known vascular, neurological, pulmonary, and fluid balance disorders, as PLE, may exacerbate these conditions. Participants who use medication and/or supplements with iatrogenic effects will also be excluded. Participants with a BMI of 40 or above will also be excluded. 

3. What does informed consent mean, and what is that process?

The study will use flyers, social media marketing, and ETBU communications to recruit participants. All potential participants showing interest will be asked to schedule an initial screening and study introduction visit at the campus health clinic. During the initial screening visits, participants will be informed that participation is voluntary. If they choose to participate, they may withdraw at any time without repercussion or loss of any benefits afforded to them. Participants will be provided with two copies of the Informed Consent Form. They will sign both forms, and their signature will be witnessed; one fully executed copy will be given to them for their personal files.

4. Are there any potential risks to participation or special precautions?

Some participants may experience slight emotional discomfort in the process of answering personal questions regarding their health. In addition, medical conditions unknown to the patient may be uncovered. These conditions could require the participant to follow up with a medical professional for a full evaluation. Participants who are untruthful about their medical history and substance usage may suffer discomfort from PLE. Participants will be reminded of this during each visit, including the initial visit, and will be reminded through text messaging on a regular basis. However, PLE risks are no greater than risks associated with activities of daily living (ADL’s). 

5. Are there any potential benefits to participation?

Participants will not receive any direct benefit as a result of this study; however, processes and/or procedures may be altered to increase the health status of participants and the health status of others. Participants will gain insight into their own health and be encouraged to use this information for personal growth to live a longer and fuller life. In addition, data may be used in studies that result in the discovery or development of major new treatments, procedures, or research. However, participants may be compensated for their time through the distribution of gift cards covering their lost time, earnings, and resources during assessment visits. This compensation will be capped at $25 per hour of time.

6. Will my data be confidential?

Completed health evaluations will be collected, analyzed by the principal investigator (Dr. Cox-Kelley) and stored in a secure locked cabinet in the PIs locked office that is physically located in a separate building from the study participants. Although the results will be reported in the aggregate, no data identifying an individual participant will be included in reports or publications about the study. Upon enrollment, participants will be assigned an identification number. At no time will any health-related data be associated with a name. At no time will your data be shared beyond the PI. The Federal Privacy Act protects the confidentiality of your records. 

However, you should know that the Act allows the release of some information from your record without your permission, for example, if it is required by members of Congress, law enforcement officials, or other authorized governmental persons.

If you have any problems or questions about this study, or about your rights as a research participant, or about any research related damage, contact the Principal Investigator, Dr. Shannon Cox at scoxkelley@etbu.edu in the Department of Biology, 903.806.3184, or Jenny Mobley Institutional Review Board (IRB) Chair, at East Texas Baptist University, 903.923.2091, jmobley@etbu.edu.

7. How will the study be designed, and how will the data be treated?

Appropriate statistical methods will be used to assess the degree to which PLE influences cardiac and digestive health. In addition, other data points will also be evaluated for correlations to health outcomes and status. These data points fall into the following categories: environmental/occupational factors, social-economic factors, medical health history, and health behavior factors. Due to the multitude of factors that will be evaluated, a multivariate correlation process will be used to assess the data. 

The multiple regression technique is the most widely used statistical technique in research and is versatile in nature, allowing the researcher to not only measure the magnitude of statistical significance but also show relationships between variables. Reasons that the multiple regression will be used include that the multiple regression can handle all data, including interval, ordinal, and categorical data. 

However, with theories attributing causal significance to predictor variables, researchers often confuse casual significance with regression weight. Because this study aims to identify and explore the depth of the causal significance of PLE and health status, the path analysis technique will be applied to any hypothetical correlation identified in the multiple regression analysis. 

The path analysis technique is a form of multiple regression in which a researcher tests the validity of a theory about causal relationships between two or more variables. This analysis differs from a simple multiple regression analysis in that it is used to test theories about hypothesized causal relationships between variables. In contrast, the multiple regression technique is used to explore the correlation between various combinations of variables. The path analysis will provide a path coefficient, which indicates the direct effect of one variable on another. 

For the regression and path analysis, a p-value of 0.5 will be the criterion to determine significance. Cronbach’s alpha will be used to evaluate the reliability, and a Sobel’s test will be used to test indirect mediating effects.