Transcutaneous oxygen tensions in assessing the treatment of healed venous ulcers

Microangiopathy in Chronic Venous Insufficiency before and after Sclerotherapy and Compression Treatment: Results of a One-Year Follow-up Study

Objective:

To characterize microangiopathy in patients with chronic venous insufficiency (CVI) of a moderate to severe stage and to evaluate improvement of the microcirculatory parameters after sclerotherapy of incompetent perforators and compression therapy.

Design:

Fluorescence videomicroscopy (Na-fluore-scein), laser Doppler fluxmetry and tc Po2 measurements (43°C) at the medial ankle in healthy controls and patients. Laser Doppler flux and tc Po2 were recorded in supine and sitting position in order to evaluate postural vasoconstriction. The measurements were repeated 6 and 12 months after sclerotherapy of incompetent perforators (Polidocanol 40 mg/ml) and compression therapy by below-knee class II or III stockings (Sigvaris®).

Setting:

Department of Internal Medicine, Angiology Division, University Hospital, Zurich, Switzerland.

Patients, participants:

15 healthy subjects (15 legs, mean age 53.3 years) and 15 patients with CVI of a moderate to severe stage (17 legs, mean age 56.8 years).

Results:

Microangiopathy in CVI is characterized by significantly enlarged, elongated and dilated capillaries with increased diameters of the pericapillary spaces (‘halos’). Single capillaries may be thrombosed. Laser Doppler flux is increased and tc Po2 is decreased. After therapy, there was a trend to decreased laser Doppler flux and an increase in tc Po2, but the differences were not statistically significant. Capillary thromboses were no longer detected. Mean halo diameters tended to decrease, but this difference was not statistically significant.

Conclusions:

Microangiopathy in CVI is characterized by morphological and functional changes. Beneficial changes induced by therapy develop slowly and emphasize the importance of long-lasting treatment.

Preventing venous ulcer recurrence: a review

This review article examines the available evidence on both the primary and secondary prevention of venous ulceration, exploring both the individual, social and financial implications of system failures that allow patients to remain at increased risk of recurrent ulceration. The role of both venous disease assessment and corrective superficial venous surgery are discussed in the light of recently published randomised controlled studies on the role of superficial venous surgery as both an adjunct to ulcer healing and ulcer prevention.

Chronic venous insufficiency and venous leg ulceration

Venous ulcers are the most common form of leg ulcers. Venous disease has a significant impact on quality of life and work productivity. In addition, the costs associated with the long-term care of these chronic wounds are substantial. Although the exact pathogenic steps leading from venous hypertension to venous ulceration remain unclear, several hypotheses have been developed to explain the development of venous ulceration. A better understanding of the current pathophysiology of venous ulceration has led to the development of new approaches in its management. New types of wound dressings, topical and systemic therapeutic agents, surgical modalities, bioengineered tissue, matrix materials, and growth factors are all novel therapeutic options that may be used in addition to the "gold standard," compression therapy, for venous ulcers. This review discusses current aspects of the epidemiology, pathophysiology, clinical presentation, diagnostic assessment, and current therapeutic options for chronic venous insufficiency and venous ulceration. (J Am Acad Dermatol 2001;44:401-21.)

LEARNING OBJECTIVE

At the conclusion of this learning activity, participants should be familiar with the 3 main types of lower extremity ulcers and should improve their understanding of the epidemiology, pathogenesis, risk factors, clinical presentation, diagnostic assessment, and current therapies for chronic venous insufficiency and venous ulcers.

Systematic Reviews of Prevention of Venous Ulcer Recurrence

Aim:

To illustrate and discuss the role of systematic reviews in assessing the effect of interventions used in preventing recurrence of venous ulceration.

Method:

Systematic review of randomised controlled trials (RCTs) reporting the recurrence of venous ulcers. We searched the Cochrane Wounds Group specialised trial register in June 2000. This contains results of searches for RCTs in 18 electronic databases and hand searches. Trials were assessed for inclusion by two people and data extraction was performed using a standard proforma.

Synthesis:

We found weak evidence that wearing compression hosiery reduces recurrence rates. There was insufficient evidence for the effectiveness of drugs, vein surgery, exercise or leg elevation.

Conclusions:

Where systematic reviews provide clear implications for practice are found, clinicians can incorporate these into treatment regimens. Where results indicate that there is clinical uncertainty, as in the prevention of recurrence, this can assist commissioners and researchers in prioritising research questions.

Investigation of chronic venous insufficiency: A consensus statement (France, March 5-9, 1997)

This consensus document provides an up-to-date account of the various methods available for the investigation of chronic venous insufficiency of the lower limbs (CVI), with an outline of their history, usefulness, and limitations. CVI is characterized by symptoms or signs produced by venous hypertension as a result of structural or functional abnormalities of veins. The most frequent causes of CVI are primary abnormalities of the venous wall and the valves and secondary changes due to previous venous thrombosis that can lead to reflux, obstruction, or both. Because the history and clinical examination will not always indicate the nature and extent of the underlying abnormality (anatomic extent, pathology, and cause), a number of diagnostic investigations have been developed that can elucidate whether there is calf muscle pump dysfunction and determine the anatomic extent and severity of obstruction or reflux. The difficulty in deciding which investigations to use and how to interpret the results has stimulated the development of this consensus document. The aim of this document was to provide an account of these tests, with an outline of their usefulness and limitations and indications of which patients should be subjected to the tests and when and of what clinical decisions can be made. This document was written primarily for the clinician who would like to learn the latest approaches to the investigation of patients with CVI and the new applications that have emerged from recent research, as well as for the novice who is embarking on venous research. Care has been taken to indicate which methods have entered the clinical arena and which are mainly used for research. The foundation for this consensus document was laid by the faculty at a meeting held under the auspices of the American Venous Forum, the Cardiovascular Disease Educational and Research Trust, the European Society of Vascular Surgery, the International Angiology Scientific Activity Congress Organization, the International Union of Angiology, and the Union Internationale de Phlebologie at the Abbaye des Vaux de Cernay, France, on March 5 to 9, 1997. Subsequent input by co-opted faculty members and revisions in 1998 and 1999 have ensured a document that provides an up-to-date account of the various methods available for the investigation of CVI.

Stanozolol as a novel therapeutic agent in dermatology

Anabolic steroids are synthetic derivatives of testosterone that were developed in the 1950s in an attempt to dissociate the anabolic and androgenic effects of testosterone. The anabolic steroid stanozolol has been particularly helpful because it has one of the largest anabolic/androgenic ratios. In addition, stanozolol has substantial fibrinolytic properties. We discuss the safety profile and the use of stanozolol for a variety of clinical applications. Stanozolol is approved for use in the treatment of hereditary angioedema, but numerous reports have detailed the effectiveness of this agent in the treatment of urticaria, Raynaud's phenomenon, and, more recently, cryofibrinogenemia and lipodermatosclerosis. Side effects are mostly dose related and are preventable with appropriate follow-up.

Comparison of transcutaneous oxygen and carbon dioxide monitors in normal adults and critically ill patients

The performance characteristics of two transcutaneous combined PO2 (tcPO2) and PCO2 (tcPCO2) sensors were compared with single tcPO2 and tcPCO2 electrodes in critically ill patients. The relationship between arterial blood gases (PaO2, PaCO2) and transcutaneous values was linear. Correlation coefficients (r) varied from 0.79 to 0.87 for tcPO2 and 0.92 to tcPCO2. The tcPO2 readings were always lower than PaO2 values, but the tcPCO2, with modified calibration of the electrodes, did not differ significantly from PaCO2. There was no significant difference of clinical importance in the performance of the three monitoring systems.