Above-Knee-High Application of Lower Limb Compression and Its Impact on Clinical Outcome in Patients Hospitalized With Heart Failure Exacerbation.

The growing number of patients with potentially heart-affecting diseases, including arterial hypertension, diabetes, and heart ischemic disease, as well as the ageing of the population, has resulted in a growing number of patients with advanced stages of CHF. The average number of days for an HF-related hospitalization in the United States is about 6 to 8 days. Hospitalization costs associated with heart failure averaged $23,077 and were higher when heart failure was a secondary rather than the primary diagnosis.

The presence of CHF results in a significant risk of leg oedema. Medical compression (MC) treatment is one of the basic methods of leg oedema elimination in patients with chronic venous disease and lymphedema, but it is not routinely considered in subjects with CHF-related swelling. In addition to chronic venous disease, bilateral leg swelling can also occur in other pathological conditions, including occupational leg oedema, lymphedema, obesity, or hypoalbuminemia. Lower extremity edema can significantly affect the patient's general condition and quality of life. The symptoms of leg heaviness, cramps \& mobility limitations could be accompanied by signs of local skin injuries, transcutaneous migration of fluid, skin discoloration or stasis dermatitis and skin induration. In more advanced and permanent swelling, the sequence of fluid transudation and epithelial maceration can lead to the development of large skin and subcutaneous tissue defects, with formation of chronic lower extremity ulcers. In cases where lower extremity lesions or wounds are already present, the presence of heart failure with volume overload can significantly impair the healing process of the local pathology.

Despite the common use of compression therapy in the treatment of leg swelling of venous and lymphatic origin, guidelines regarding its potential use in HF-related edema have not been specified. This is due to lack of sufficient number of properly performed studies in this field as well as a heterogenous population of heart failure patients with several classes of disease severity. As documented in the available literature, compression treatment can potentially be used in selected HF patients.

Patients who are admitted with heart failure exacerbation with clinical evidence of volume overload in the form of lower extremity edema will be randomly assigned in a 1:1 ratio to either the Control group or Compression group.

Patients, care providers (Heart failure specialist) and outcome-assessing physicians would be blinded to arm assignment.

Patients in the Compression group would be subject to application of standardized lower extremity, thigh-high, elastic compression stockings within 24 hours of admission, and would remain in place during the entire hospital stay, provided the patient is able to tolerate it.

In addition, the patients would be closely monitored with daily skin checks for cutaneous lesions and daily transthoracic echocardiograms for estimation on cardiac pressures.

Orthostatic vitals signs would be checked on Day 2 or Day 3 of hospitalization by a member of the study team.

In the Control group, the inflatable sleeves of a sequential compression device would be placed in bilateral lower extremities, but the device would not be turned on, thus no external pressure would be applied. All other measures would be identical to the Compression group.

Both groups of patients would receive standard care for heart failure exacerbation.

The primary outcomes would be-

1. Length of stay in the hospital, calculated by subtracting the day of admission from day of discharge. Incidence of rehospitalization due to heart failure exacerbation within the first 30 days as well as within the first 90 days after discharge from index hospitalization. Patients would have been recruited and subject to our intervention at the index hospitalization.
2. Duration of index hospitalization.

The secondary outcomes would be incidence of rehospitalization due to heart failure exacerbation within the first 30 days as well as within the first 90 days after discharge from index hospitalization. In addition, the following would also be secondary outcomes of our study: death from all causes, cardiovascular deaths, and major adverse cardiac event within 30 days of discharge from index hospitalization, incidence of AKI, total duration of IV diuretics therapy, percent change in serum BNP level at discharge in comparison to admission. Incidence of orthostatic hypotension and incidence of cutaneous lesions following application of compression stockings would be secondary outcomes as well.

Following IRB approval, the recruiting process will begin with a target of including 100 patients in the study. Tentative timeline for completion of the study would be three (3) years.

Patients who meet the inclusion criteria of the study will be randomly assigned in a 1:1 ratio to either the Control group or Compression group. Randomization will be performed by data analysis software, which would determine whether the patient would fall under the lower extremity Compression arm vs Control (no compression) arm.

Patients in the Compression group would be subject to application of standardized lower extremity, thigh-high, elastic compression stockings within 24 hours of admission. The stockings used at UTMB are known to exert a pressure ranging from 15-18 mmHg, with the greatest pressure being exerted at the ankle (18 mmHg) and gradual reduction throughout the length of the leg to 15 mmHg. Appropriate size of the stockings would be based on calf circumference, thigh circumference and leg length. The compression would be applied throughout the entire duration of hospitalization, provided the patient is able to tolerate it. Daily thorough skin checks for any cutaneous defects or lesions will be performed, and mobilization encouraged. Orthostatic blood pressure would be checked at least 24 hours after application of compression stockings, either on day 2 or 3 of hospitalization. In addition, bedside Transthoracic Echocardiograms would be done prior to the application of compression and on a daily basis after the stockings had been placed to monitor intra-cardiac pressures. However, the pressures obtained from echocardiogram would not be made available to the heart failure team to ensure that the ongoing treatment is not affected in any way by echocardiographic findings of the study team.

The investigators would measure thigh and calf circumference every day. If there is a change (either increase or decrease) in the circumferences by 3-5 cm from the previous day, investigators would consider changing the size of compression stocking based on the new measurements.

In the Control group, the inflatable sleeves of a sequential compression device would be placed in bilateral lower extremities, but the device would not be turned on, thus no external pressure would be applied. Orthostatic blood pressure measurements, daily skin checks and bedside echocardiograms prior to and after application of lower extremity sleeves would be performed similar to the compression group. No extra costs on the part of the patient would be necessary.