Fluid Shifts Induced by Physical Therapy in Lower Limb Lymphedema Patients

Capillary leak and endothelial permeability in critically ill patients: a current overview

Capillary leak syndrome (CLS) represents a phenotype of increased fluid extravasation, resulting in intravascular hypovolemia, extravascular edema formation and ultimately hypoperfusion. While endothelial permeability is an evolutionary preserved physiological process needed to sustain life, excessive fluid leak-often caused by systemic inflammation-can have detrimental effects on patients' outcomes. This article delves into the current understanding of CLS pathophysiology, diagnosis and potential treatments. Systemic inflammation leading to a compromise of endothelial cell interactions through various signaling cues (e.g., the angiopoietin-Tie2 pathway), and shedding of the glycocalyx collectively contribute to the manifestation of CLS. Capillary permeability subsequently leads to the seepage of protein-rich fluid into the interstitial space. Recent insights into the importance of the sub-glycocalyx space and preserving lymphatic flow are highlighted for an in-depth understanding. While no established diagnostic criteria exist and CLS is frequently diagnosed by clinical characteristics only, we highlight more objective serological and (non)-invasive measurements that hint towards a CLS phenotype. While currently available treatment options are limited, we further review understanding of fluid resuscitation and experimental approaches to target endothelial permeability. Despite the improved understanding of CLS pathophysiology, efforts are needed to develop uniform diagnostic criteria, associate clinical consequences to these criteria, and delineate treatment options.

A Prospective Preliminary Study Examining the Physiological Impact of Pneumatic Compression Dosing in the Treatment of Lower Extremity Lymphedema

Background: Optimal frequency and duration of pneumatic compression device (PCD) therapy for lymphedema is undetermined. This prospective, randomized preliminary study evaluated the impact of different PCD dosing protocols on physiological and patient-reported outcomes (PROs) to estimate treatment effects, assess the responsiveness of various measurement techniques, and identify endpoints for a definitive PCD dosing trial. Methods and Results: Twenty-one patients with lower extremity lymphedema were randomized into three groups for treatment with the Flexitouch advanced PCD: (A) once per day for 1 hour, 12 consecutive days; (B) twice per day in 1-hour treatments, 5 consecutive days; or (C) twice per day in 2-hour treatments, 5 consecutive days. Outcomes measured were changes in limb volume (LV), tissue fluid, tissue tone, and PROs. Those in group A experienced mean (standard deviation) LV reductions of 109 (58) mL (p = 0.003) on day 1 and of 97 (86) mL (p = 0.024) on day 5. Group A also showed possible single-treatment decreases in extracellular fluid volume by bioimpedance spectroscopy (BIS) on day 5. There were no consistent changes in groups B and C. Long-term assessment of LV and BIS showed no clear change. Tonometry, ultrasound, local tissue water, and PROs showed wide variation among participants. Conclusions: LV measurements showed potential benefit for 1-hour daily PCD treatment. A definitive dosing trial should include LV, BIS, and PROs in a comparison of 1- and 2-hour daily treatment protocols conducted over a study period of 4 weeks. These data may inform appropriate outcome measures for other intervention studies in lymphedema.

The efficacy of change in limb volume on functional mobility, health-related quality of life, social appearance anxiety, and depression in patients with lower extremity lymphedema

Objectives

This study aims to investigate the impact of change in limb volume on the levels of functional mobility, health-related quality of life, social appearance anxiety, and depression before and after complex decongestive physiotherapy in patients with lower extremity lymphedema.

Method

Twenty-seven patients with unilateral lower extremity lymphedema were included. The treatment period was 20 sessions. The outcome measures were the limb volume, the Timed Up and Go test, the Short Form-36, the Social Appearance Anxiety Scale, and the Beck Depression Inventory.

Results

A statistically significant decrease in the limb volume ( p < 0.001) and statistically significant improvements in the Timed Up and Go test performance ( p < 0.001), the Short Form-36 Physical Component Summary score ( p < 0.01), the Social Appearance Anxiety Scale score ( p < 0.001), and the Beck Depression Inventory score ( p < 0.001) were found. No statistically significant difference was found on the Short Form-36 Mental Component Summary score ( p > 0.05).

Conclusion

The decrease in the limb volume improves the functional mobility, physical health-related quality of life, social appearance anxiety, and depression in patients with lower extremity lymphedema, but not the mental health-related quality of life.

Estimation of the Lymph Flow Through Thoracic Duct in Human Subjects Using the Urine Osmolarity: Applicable for Evaluating the Effectiveness of Manual Lymph Drainage

Currently, there are many methods to evaluate the effectiveness of manual lymph drainage in the treatment of lymphedema, that is, limb volume measurement, bio-electrical impedance measurement, computer tomography, and ultrasound imaging. However, it is difficult for these methods to accurately address the lymph flow generated by manual lymph drainage. Therefore, we aimed at developing a concise and accurate method to measure the lymph flow through the thoracic duct in human subjects, which is applicable for evaluating the effectiveness of manual lymph drainage. In the present mini-review, we demonstrate the developed method in detail and its scientific evidence for the effectiveness obtained with animal and human clinical experiments. In rat in vivo experiments, intragastric administration of distilled water significantly increased mesenteric flow, which was transported via the cisterna chyli and then the thoracic duct. The manual massage on the cisterna chyli in the anesthetized rabbit significantly accelerated the lymph flow through the thoracic duct, resulting in marked hemodilution. Abdominal respiration in the supine position in human subjects produced similar hemodilution, with a marked decrease in the concentration of vasopressin in the blood. On this basis, we developed a new method to accurately measure the lymph flow through the thoracic duct by using changes in the concentration of vasopressin in the blood. In addition, with changes in urine osmolarity depending on the concentration of vasopressin in the blood, we developed a more concise and noninvasive method for evaluating the lymph flow through the thoracic duct in human subjects. These methods may be applicable for evaluating the effectiveness for the manual lymph drainage in the patients with lymphedema.

Hemodynamic Responses in Lower Limb Lymphedema Patients Undergoing Physical Therapy

BACKGROUND

Lymphedema arises due to a malfunction of the lymphatic system, leading to extensive tissue swelling. Complete decongestive therapy (CDT), which is a physical therapy lasting for 3 weeks and includes manual lymphatic drainages (MLD), leads to fluid mobilization and increases in plasma volume. Here, we investigated hemodynamic responses induced by these fluid shifts due to CDT and MLD.

METHODS

Hemodynamic parameters were assessed continuously during a sit-to-stand test (5 min baseline, 5 min of standing, and 5 min of recovery). This intervention was repeated on days 1, 2, 7, 14, and 21 of CDT, before and after MLD. Volume regulatory hormones were assessed in plasma samples.

RESULTS

A total number of 13 patients took part in this investigation. Resting diastolic blood pressure significantly decreased over three weeks of CDT (p = 0.048). No changes in baseline values were shown due to MLD. However, MLD led to a significant decrease in heart rate during orthostatic loading over all epochs on therapy day 14, as well as day 21. Volume regulatory hormones did not show changes over lymphedema therapy.

CONCLUSION

We did not observe any signs of orthostatic hypotension at rest, as well as during to CDT, indicating that lymphedema patients do not display an elevated risk of orthostatic intolerance. Although baseline hemodynamics were not affected, MLD has shown to have potential beneficial effects on hemodynamic responses to a sit-to-stand test in patients undergoing lymphedema therapy.

Lymphatic Senescence: Current Updates and Perspectives

Simple Summary

The lymphatic system is involved in tissue homeostasis, immune processes as well as transport of lipids, proteins and pathogens. Aging affects all physiological systems. However, it is not well studied how aging affects the lymphatic vasculature. Therefore, this review aims at investigating how senescence could lead to changes in the structure and function of the lymphatic vessels. We report that lymphatic senescence is associated with alterations in lymphatic muscles and nerve fibers, lymphatic endothelial cells membrane dysfunction, as well as changes in lymphatic pump, acute inflammation responses and immune function.

Abstract

Lymphatic flow is necessary for maintenance of vital physiological functions in humans and animals. To carry out optimal lymphatic flow, adequate contractile activity of the lymphatic collectors is necessary. Like in all body systems, aging has also an effect on the lymphatic system. However, limited knowledge is available on how aging directly affects the lymphatic system anatomy, physiology and function. We investigated how senescence leads to alterations in morphology and function of the lymphatic vessels. We used the strategy of a review to summarize the scientific literature of studies that have been published in the area of lymphatic senescence. Searches were carried out on PubMed and Web of Science using predefined search queries. We obtained an initial set of 1060 publications. They were filtered to 114 publications based on strict inclusion and exclusion criteria. Finally, the most appropriate 57 studies that specifically addressed lymphatic senescence have been selected for the preparation of this review. Analysis of the literature showed that lymphatic senescence is associated with alterations in lymphatic muscles and nerve fibers, lymphatic glycocalyx function of lymphatic endothelial cells, effects of chronic ultraviolet light exposure and oxidative stress as well as changes in lymphatic pump, acute inflammation responses and immune function. The current review underscores the relevance of the understudied area of lymphatic senescence. Continued research on the impact of aging on the structure and function of the lymphatic vasculature is needed to provide further insights to develop innovative clinical diagnostic—and treatment—modalities as well as to reduce the morbidity associated with diseases related to the lymphatic system.

Biology of Lymphedema

Simple Summary

Lymphedema is a chronic, debilitating disease of the lymphatic vasculature. Although several reviews focus on the anatomy and physiology of the lymphatic system, this review provides an overview of the lymphatic vasculature and, moreover, of lymphatic system dysfunction and lymphedema. Further, we aim at advancing the knowledge in the area of lymphatic system function and how dysfunction of the lymphatic system—as seen in lymphedema—affects physiological systems, such as the cardiovascular system, and how those might be modulated by lymphedema therapy.

Abstract

This narrative review portrays the lymphatic system, a poorly understood but important physiological system. While several reviews have been published that are related to the biology of the lymphatic system and lymphedema, the physiological alternations, which arise due to disturbances of this system, and during lymphedema therapy, are poorly understood and, consequently, not widely reported. We present an inclusive collection of evidence from the scientific literature reflecting important developments in lymphedema research over the last few decades. This review aims at advancing the knowledge on the area of lymphatic system function as well as how system dysfunction, as seen in lymphedema, affects physiological systems and how lymphedema therapy modulates these mechanisms. We propose that future studies should aim at investigating, in-detail, aspects that are related to fluid regulation, hemodynamic responses, and endothelial and/or vascular changes due to lymphedema and lymphedema therapy.

Effects of physical therapy on hyaluronan clearance and volume regulating hormones in lower limb lymphedema patients: A pilot study

Lymphedema is manifested as a chronic swelling arising due to stasis in the lymphatic flow. No cure is currently available. A non-invasive treatment is a 3 week complete decongestive therapy (CDT), including manual lymphatic drainage and compression bandaging to control swelling. As CDT leads to mobilization of several liters of fluid, effects of CDT on hyaluronan clearance (maker for lymphatic outflow), volume regulating hormones, total plasma protein as well as plasma density, osmolality and selected electrolytes were investigated. In this pilot study, we assessed hyaluronan and volume regulating hormone responses from plasma samples of nine patients (three males, six females, aged 55 ± 13 years) with lower limb lymphedema stage II-III, before - and after - CDT. A paired non-parametric test (Wilcoxon) was used to assess hormonal and plasma volume changes. Correlation was tested using Spearman's correlation. The main findings of this novel study are that lymphedema patients lost volume and weight after therapy. Hyaluronic acid did not significantly change pre- compared to post-CDT. Aldosterone increased significantly after therapy, while plasma renin activity increased, but not significantly. Plasma total protein, density, osmolality and sodium and chloride did not show differences after CDT. To our knowledge, no study has previously investigated the effects of CDT on volume regulating hormones or electrolytes. To identify the time-course of volume regulating hormones and lymphatic flow changes induced by CDT, future studies should assess these parameters serially over 3 weeks of therapy.