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Counteracting negative venous line pressures to avoid arterial air bubbles: an experimental study comparing two different types of miniaturized extracorporeal perfusion systems.

Aboud A, Mederos-Dahms H, Liebing K, Zittermann A, Schubert H, Murray E, Renner A, Gummert J, Börgermann J - BMC Anesthesiol (2015)

Bottom Line: In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation.The use of a miniaturized perfusion system with a volume replacement reservoir is able to counteract excessive negative venous line pressures and to reduce the number and volume of arterial air bubbles.This approach may lead to a lower rate of neurological complications.

View Article: PubMed Central - PubMed

Affiliation: Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center NRW, Ruhr University Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany. aaboud@hdz-nrw.de.

ABSTRACT

Background: Because of its low rate of clinical complications, miniaturized extracorporeal perfusion systems (MEPS) are frequently used in heart centers worldwide. However, many recent studies refer to the higher probability of gaseous microemboli formation by MEPS, caused by subzero pressure values. This is the main reason why various de-airing devices were developed for today's perfusion systems. In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation.

Methods: In an experimental study on 26 pigs, we compared MEPS (n = 13) with MEPS plus OVR (n = 13). Except OVR, perfusion equipment was identical in both groups. Primary endpoints were pressure values in the venous line and the right atrium as well as the number and volume of air bubbles. Secondary endpoints were biochemical parameters of systemic inflammatory response, ischemia, hemodilution and hemolysis.

Results: One animal was lost in the MEPS + OVR group. In the MEPS + OVR group no pressure values below -150 mmHg in the venous line and no values under -100 mmHg in right atrium were noticed. On the contrary, nearly 20% of venous pressure values in the MEPS group were below -150 and approximately 10% of right atrial pressure values were below -100 mmHg. Compared with the MEPS group, the bubble counter device showed lower numbers of arterial air bubbles in the MEPS + OVR group (mean ± SD: 13444 ± 5709 vs. 1 ± 2, respectively; p < 0.001). In addition, bubble volume was significantly lower in the MEPS + OVR group than in the MEPS group (mean ± SD: 1522 ± 654 μl vs. 4 ± 6 μl, respectively; p < 0.001). The proinflammatory cytokine interleukin-6 and biochemical indices of cardiac ischemia (creatine kinase, and troponin I) were comparable between both groups.

Conclusions: The use of a miniaturized perfusion system with a volume replacement reservoir is able to counteract excessive negative venous line pressures and to reduce the number and volume of arterial air bubbles. This approach may lead to a lower rate of neurological complications.

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Related in: MedlinePlus

Mean number of gaseous microemboli in the arterial and venous line according to study group. ***P < 0.001 miniaturized extracorporeal perfusion system plus volume replacement reservoir group vs. miniaturized extracorporeal perfusion system group
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Fig3: Mean number of gaseous microemboli in the arterial and venous line according to study group. ***P < 0.001 miniaturized extracorporeal perfusion system plus volume replacement reservoir group vs. miniaturized extracorporeal perfusion system group

Mentions: The percentage of venous line and right atrial pressures in each pressure category is presented in Table 1. Compared with the MEPS group, the pressure values in the venous line as well as in the right atrium were significantly higher in the MEPS + OVR group: Approximately 80 % of venous pressure values were above −50 mmHg and only a few values were between −75 and −149 mmHg in the MEPS + OVR group. No values below −150 mm Hg were observed. Low pressure values occurred much more frequently in the MEPS group. Nearly 20 % of venous pressure values were below −150 mmHg and approximately 30 % of right atrial pressure values were below −30 mmHg in the MEPS group, 9.5 % were below −100 mmHg. The low pressure values in the MEPS group were accompanied by a much higher number of arterial and venous air bubbles than in the MEPS + OVR group (Fig. 3). In detail, the number of air bubbles in the arterial line was 13444 ± 5709 vs. 1 ± 2 (p < 0.001), and 16640 ± 16070 vs. 49 ± 60 (p < 0.001) in the venous line. In addition, the volume of the arterial and venous bubbles was much higher during MEPS than during MEPS + OVR (Fig. 4). Arterial air bubbles during MEPS and MEPS + OVR had a volume of 1522 ± 654 μl and 4 ± 6 μl, respectively (p < 0.001). Venous air bubbles had a volume of 1683 ± 1322 μl during MEPS vs. 21 ± 52 μl during MEPS + OVR (p < 0.001).Table 1


Counteracting negative venous line pressures to avoid arterial air bubbles: an experimental study comparing two different types of miniaturized extracorporeal perfusion systems.

Aboud A, Mederos-Dahms H, Liebing K, Zittermann A, Schubert H, Murray E, Renner A, Gummert J, Börgermann J - BMC Anesthesiol (2015)

Mean number of gaseous microemboli in the arterial and venous line according to study group. ***P < 0.001 miniaturized extracorporeal perfusion system plus volume replacement reservoir group vs. miniaturized extracorporeal perfusion system group
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4459480&req=5

Fig3: Mean number of gaseous microemboli in the arterial and venous line according to study group. ***P < 0.001 miniaturized extracorporeal perfusion system plus volume replacement reservoir group vs. miniaturized extracorporeal perfusion system group
Mentions: The percentage of venous line and right atrial pressures in each pressure category is presented in Table 1. Compared with the MEPS group, the pressure values in the venous line as well as in the right atrium were significantly higher in the MEPS + OVR group: Approximately 80 % of venous pressure values were above −50 mmHg and only a few values were between −75 and −149 mmHg in the MEPS + OVR group. No values below −150 mm Hg were observed. Low pressure values occurred much more frequently in the MEPS group. Nearly 20 % of venous pressure values were below −150 mmHg and approximately 30 % of right atrial pressure values were below −30 mmHg in the MEPS group, 9.5 % were below −100 mmHg. The low pressure values in the MEPS group were accompanied by a much higher number of arterial and venous air bubbles than in the MEPS + OVR group (Fig. 3). In detail, the number of air bubbles in the arterial line was 13444 ± 5709 vs. 1 ± 2 (p < 0.001), and 16640 ± 16070 vs. 49 ± 60 (p < 0.001) in the venous line. In addition, the volume of the arterial and venous bubbles was much higher during MEPS than during MEPS + OVR (Fig. 4). Arterial air bubbles during MEPS and MEPS + OVR had a volume of 1522 ± 654 μl and 4 ± 6 μl, respectively (p < 0.001). Venous air bubbles had a volume of 1683 ± 1322 μl during MEPS vs. 21 ± 52 μl during MEPS + OVR (p < 0.001).Table 1

Bottom Line: In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation.The use of a miniaturized perfusion system with a volume replacement reservoir is able to counteract excessive negative venous line pressures and to reduce the number and volume of arterial air bubbles.This approach may lead to a lower rate of neurological complications.

View Article: PubMed Central - PubMed

Affiliation: Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center NRW, Ruhr University Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany. aaboud@hdz-nrw.de.

ABSTRACT

Background: Because of its low rate of clinical complications, miniaturized extracorporeal perfusion systems (MEPS) are frequently used in heart centers worldwide. However, many recent studies refer to the higher probability of gaseous microemboli formation by MEPS, caused by subzero pressure values. This is the main reason why various de-airing devices were developed for today's perfusion systems. In the present study, we investigated the potential benefits of a simple one-way-valve connected to a volume replacement reservoir (OVR) for volume and pressure compensation.

Methods: In an experimental study on 26 pigs, we compared MEPS (n = 13) with MEPS plus OVR (n = 13). Except OVR, perfusion equipment was identical in both groups. Primary endpoints were pressure values in the venous line and the right atrium as well as the number and volume of air bubbles. Secondary endpoints were biochemical parameters of systemic inflammatory response, ischemia, hemodilution and hemolysis.

Results: One animal was lost in the MEPS + OVR group. In the MEPS + OVR group no pressure values below -150 mmHg in the venous line and no values under -100 mmHg in right atrium were noticed. On the contrary, nearly 20% of venous pressure values in the MEPS group were below -150 and approximately 10% of right atrial pressure values were below -100 mmHg. Compared with the MEPS group, the bubble counter device showed lower numbers of arterial air bubbles in the MEPS + OVR group (mean ± SD: 13444 ± 5709 vs. 1 ± 2, respectively; p < 0.001). In addition, bubble volume was significantly lower in the MEPS + OVR group than in the MEPS group (mean ± SD: 1522 ± 654 μl vs. 4 ± 6 μl, respectively; p < 0.001). The proinflammatory cytokine interleukin-6 and biochemical indices of cardiac ischemia (creatine kinase, and troponin I) were comparable between both groups.

Conclusions: The use of a miniaturized perfusion system with a volume replacement reservoir is able to counteract excessive negative venous line pressures and to reduce the number and volume of arterial air bubbles. This approach may lead to a lower rate of neurological complications.

Show MeSH
Related in: MedlinePlus