Automated Measurements of Ankle-Brachial Index: A Narrative Review

Peripheral artery disease (PAD) is an atherosclerotic disease that causes obstruction in lower limb arteries. It increases cardiovascular risk even in asymptomatic patients. Accurate diagnostic tools for identification of affected individuals are needed. Recently, there have been attempts to establish a reliable method of automated ankle-brachial index (ABI) identification. A search of PubMed database to identify studies assessing automatic ABI measurements in agreement with standard PAD diagnosis methods was conducted in December 2020. A total of 57 studies were analyzed in the review. The majority of analyzed studies found ABI measured by automatic oscillometric devices to be potentially feasible for use. Some note that, even though the Doppler and oscillometric methods are not fully interchangeable, the oscillometric devices could be used in screening. Significantly fewer publications are available on automatic plethysmographic devices. For photoplethysmography, most studies reported either good or moderate agreement with reference standards. For air plethysmography, poorer agreement with Doppler ABI is suggested. It is noted that pulse volume recording (PVR) function may improve the diagnostic accuracy of the devices.

FEATURES OF THE NUTRITIVE STATUS OF PREMATURE INFANTS WITH BRONCHOPULMONARY DYSPLASIA IN THE FIRST HALF-YEAR OF LIFE

Objective of the study: assessment of the nutritional status of infants with bronchopulmonary dysplasia. Materials and methods of research: a retrospective uncontrolled non-randomized cross-sectional comparative study was carried out. It involved 40 premature babies (boys – 19, girls – 21) at the corrected age of 3,3 [2,3–4,0] months and 16 age matched full-term babies (comparison group). Children born prematurely were divided into 2 groups depending on their body mass (BM) at birth: 1st – 25 children with BM less than 1500 g, 2nd – 15 children with BM from 1500 to 2500 g. The first group included subgroups 1A and 1B, depending on the presence or absence of bronchopulmonary dysplasia in children. Physical development was assessed using INTERGROWTH-21st and WHO Anthro, 2009 anthropometric calculators, body composition was determined by air plethysmography using a PEA POD apparatus. Results: the assessment of anthropometric indices (WAZ and HAZ) calculated for postnatal and corrected age revealed the most severe manifestations of nutritional deficiency in children with very low BM at birth who developed bronchopulmonary dysplasia. The percentage of fatty BM was statistically significantly lower in children of subgroups 1A and 1B compared to full-term infants (p<0,006), as well as fatfree BM (p<0,012). Conclusion: the slow development of anthropometric indicators of premature babies with very low BM, especially those with bronchopulmonary dysplasia, indicates the need for timely correction of their nutrition.

Influence of Superficial Venous Ablation on Deep Venous Dilation and Reflux in Patients With Saphenous Varicose Veins

Background: To investigate the influence of superficial venous ablation on deep venous dilation and reflux in patients with saphenous varicose veins, and to elucidate the association between superficial venous reflux and deep venous morphology and hemodynamics. Methods: The data of 154 patients with 223 limbs, who underwent endovenous radiofrequency ablation (RFA) of the great saphenous vein for primary varicose veins between September 2014 and March 2016 in Eniwa Midorino Clinic, were retrospectively analyzed. Overall venous hemodynamics of the leg, including functional venous volume (VV) and venous filling index (VFI), was assessed using air-plethysmography. Saphenous and deep vein reflux and diameter were evaluated with duplex scanning. Results: Hemodynamic and morphologic changes were evaluated before and 1 month after RFA. The VV and VFI were significantly decreased in postoperative values than in preoperative values ( P < .001). Limbs with deep venous reflux significantly decreased postoperatively than preoperatively ( P < .001). There were significant differences in the diameter of the common femoral vein (CFV) and popliteal vein (PV) between the preoperative and postoperative values ( P < .001). There were strong to moderate correlations between the VV and the diameter of the CFV or PV (CFV, r = 0.47, P < .001; PV, r = 0.35, P < .001), while there were moderate to weak correlations between the VFI and the diameter of the CFV or PV (CFV, r = 0.23, P < .001; PV, r = 0.33, P <.001). Conclusions: Superficial venous ablation significantly reduced deep venous dilation and reflux in patients with saphenous varicose veins. Significant correlations existed between the VV or VFI, which reflected superficial venous reflux, and the diameter of the deep veins. These findings reveal that volume overload due to superficial venous reflux is associated with deep venous morphology and hemodynamics.

Welches ist der Stellenwert der Luft-Plethysmographie zur Diagnostik der Iliakal-Venen-Obstruktion?

ZusammenfassungDurch die Möglichkeit der Stenteinlage in iliakale Venen scheint die Behandlung der zentralen Obstruktion ein leichtes Unterfangen geworden zu sein. Allerdings bedingt diese Behandlung eine zumindest vorübergehende Antikoagulation – und der Stent wird lebenslang im Bein verbleiben. Und die Evaluation der Ergebnisse ist noch nicht gut etabliert. Auch die Indikationsstellung ist nicht immer objektivierbar gegeben, wenn man bedenkt, dass 25 % der Bevölkerung eine Stenose der linken V. iliaca von über 50 % aufweisen, auch wenn sie meist keine Symptome haben. Erschwerend kommt hinzu, dass die venöse chronische Insuffizienz als klinisches Syndrom (CVI) mehrere Ursachen haben kann, wie Varikose, Obstruktion oder Refluxe der tiefen Achse und die Behandlung eines einzelnen, anatomischen Befundes nicht unbedingt die Klinik nachhaltig verbessern muss. Die Luft-Plethysmographie (Air Plethysmography, APG) bietet in diesem Zusammenhang eine objektive, vom Untersucher und vom Patienten unabhängige Auswertungsmöglichkeit für die venöse Drainage und für die venöse Wiederauffüllzeit, die in jedem Fall vor einem Eingriff der zentralen Venen und zur Evaluation des Ergebnisses gefordert werden sollte.

Pressure dynamics in chronic venous disease

Peripheral venous pressure is regulated by central and peripheral mechanisms. Peripheral venous hypertension is an important pathologic component of chronic venous disease and is present in about two-third of patients with chronic venous disease. It can result from reflux, obstructive lesions or high arterial inflow. The dominant influence in patients with peripheral venous hypertension appears to be obstruction rather than reflux. Reflux can be superficial or deep or both. In about 70% of patients with reflux, valvular incompetence is present in the superficial, deep and perforator systems in some combination. In an ex vivo experimental model, conduit pressure increased with smaller native or functional caliber, focal stenosis and increased post-capillary inflow. Venous pressure in the lower limb can be measured in a variety of ways: supine resting pressure, erect resting pressure and ambulatory venous pressure. These measurements are affected by factors such as intra-abdominal pressure, intra-thoracic pressure, gravity, venoarteriolar reflux, valve reflux and venous obstruction. Venous obstruction is associated with elevated supine pressures while reflux is associated with elevated erect resting and ambulatory venous pressures. Ambulatory venous pressure reflects venous hypertension in patients with advanced venous disease. However, our investigation has shown that ambulatory venous pressure hypertension is rarely present if air plethysmography testing is negative. Consideration maybe given to the omission of the ambulatory venous pressure testing if air plethysmography testing is normal.