Ultrasonographic investigation of the effect of positive end-expiratory pressure on the cross-sectional area of the femoral vein

Abstract

Femoral veins are commonly used as a relatively safe alternative route for central venous cannulation. Several maneuvers are used to increase the cross-sectional area of the vein. In this study, we assessed the effect of positive end-expiratory pressure (PEEP) on the cross-sectional area (CSA) of femoral veins, using ultrasound in adult patients under positive pressure ventilation. All patients received a standardized induction of general anesthesia and intravenous fluid administration. Using ultrasound, the cross-sectional areas of both femoral veins were measured in 57 adult patients in the supine position without PEEP (control) and in the supine position with PEEP of 10 cm H(2)O. Mean arterial pressure and heart rate were recorded before and after the application of PEEP at 10 cm H(2)O. The application of 10 cm H(2)O PEEP significantly increased the CSA of the right femoral vein by 47.6 % and the left femoral vein by 48.4 % (each P < 0.001). Mean arterial pressure decreased by 2.6 mmHg (95 % CI 1.3-3.9; P < 0.001), whereas no significant change in heart rate was observed (P = 0.861). The CSA of the femoral vein is augmented with the application of 10 cm H(2)O PEEP in adult patients undergoing positive pressure ventilation.

Novel body positioning maximizes femoral venous size in adults: An ultrasonographic evaluation

“…The frog leg and back‐up position are hard to be blinded for the operator. Fourth, positive end expiratory pressure during mechanical ventilation can influence the CSA of FV, 11 and further research is warranted to answer to this question.…”

“…A single MyLab TM Seven (Esaote, Genoa, Italy) US scanner was used for evaluating right FV CSA and diameter. The site of right femoral venipuncture (1 to 2 cm below the midpoint of the inguinal ligament) by where a clinician would traditionally attempt cannulation of the FV 7 , 9 was scanned transversely with a 13–4 MHz broadband linear probe (Esaote SL1543 Ultrasound Transducer) by a single emergency physician with the lightest possible pressure to decrease effect on the size of FV by the degree of compression 10 , 11 …”

“…The site of right femoral venipuncture (1 to 2 cm below the midpoint of the inguinal ligament) by where a clinician would traditionally attempt cannulation of the FV 7,9 was scanned transversely with a 13-4 MHz broadband linear probe (Esaote SL1543 Ultrasound Transducer) by a single emergency physician with the lightest possible pressure to decrease effect on the size of FV by the degree of compression. 10,11 US images were obtained in order of the neutral, back-up, frog leg, and back-up/frog leg position. To exclude the effects of respiratory fluctuations, maximal CSA and diameter were selected.…”

Cross-sectional area of the femoral vein varies with leg position and distance from the inguinal ligament

“…Among proposed methods are the Valsalva maneuver, PEEP, and manual abdominal compression. Also reversed Trendelenburg position was advised to increase the size of the vessel [ 9 , 10 ]. Another approach focuses on the position of the lower limb on the side where the puncture is planned.…”

“…The risk of adverse events related to the procedure could be most likely reduced with choosing the puncture site where the cross-sectional area of the vein is the largest, the distance between the skin surface and the vessel is the shortest, but also the distance from the inguinal ligament is the greatest (to avoid retroperitoneal hematomas). Different approaches were proposed to make the femoral vein more accessible, including Valsalva maneuver, reverse Trendelenburg position, abdominal compression or positive end-expiratory pressure (PEEP) [ 9 , 10 ]. However, there are studies showing that simple change of patient’s lower limb position can significantly increase femoral vein’s size.…”