Gudmundsson F F, Viste A, Gislason H, Svanes K
Surgical Research Laboratory, Haukeland University Hospital, University of Bergen, 5021 Bergen, Norway.
Intensive Care Med. 2002 Apr;28(4):509-14. doi: 10.1007/s00134-001-1187-0. Epub 2002 Jan 15.
Intra-abdominal pressure (IAP) can be measured in different ways but is usually measured indirectly via the urinary bladder. The aim of the study was to: 1) compare urinary bladder pressure, femoral vein pressure, and inferior caval vein pressure with IAP at different levels of IAP; and 2) try to find an optimal amount of fluid to be instilled into the urinary bladder before measurement of the bladder pressure, and to compare changes in blood flow in the femoral vein with that in the caval vein at different pressure levels.
Experimental study.
Animal research laboratory.
Eight domestic swine of both sexes, weighing 30.6+/-2.9 kg (mean+/-SD).
Catheters connected to pressure transducers were placed into the urinary bladder, the inferior caval vein, the femoral vein, and the superior caval vein. Transit time flow probes were placed around the inferior caval vein and the femoral vein. After a stabilizing period, the abdominal pressure was increased stepwise by instillation of Ringer's solution into the abdomen and then decreased. Thereafter, we instilled fluid into the bladder at an IAP of 8 mmHg and at 20 mmHg and measured the amount of fluid needed to elevate the intra-vesical pressure by 2 mmHg.
The pressures recorded in the urinary bladder, the inferior caval vein, and the femoral vein reflected the pressure in the abdominal cavity very well. The fluid volume needed to increase the bladder pressure by 2 mmHg was significantly lower at 20 mmHg IAP than at 8 mmHg. Blood flow in the femoral vein and the inferior caval vein showed a similar pattern and decreased when the intra-abdominal pressure increased.
In our porcine model, and increasing the IAP by means of instillation of Ringer's solution, a reliable estimation of the IAP was obtained by measuring the pressure in the urinary bladder, the femoral vein or the inferior caval vein. The IAP estimated indirectly as the urinary bladder pressure is affected by the amount of fluid in the bladder, which should not exceed 10-15 ml. The decrease in femoral vein blood flow reflects the changes in inferior caval vein flow during increased IAP.
腹内压（IAP）可通过不同方法测量，但通常通过膀胱间接测量。本研究的目的是：1）比较在不同IAP水平下膀胱压力、股静脉压力和下腔静脉压力与IAP；2）试图找出在测量膀胱压力前注入膀胱的最佳液体量，并比较不同压力水平下股静脉与腔静脉血流的变化。
实验研究。
动物研究实验室。
8头家猪，雌雄不限，体重30.6±2.9千克（均值±标准差）。
将连接压力传感器的导管分别置入膀胱、下腔静脉、股静脉和上腔静脉。在下腔静脉和股静脉周围放置渡越时间血流探头。在稳定期后，通过向腹腔内注入林格液使腹压逐步升高，然后降低。此后，在IAP为8 mmHg和20 mmHg时向膀胱内注入液体，并测量使膀胱内压升高2 mmHg所需的液体量。
膀胱、下腔静脉和股静脉记录的压力能很好地反映腹腔内压力。在IAP为20 mmHg时使膀胱压力升高2 mmHg所需的液体量明显低于8 mmHg时。股静脉和下腔静脉的血流呈现相似模式，且在腹内压升高时减少。
在我们的猪模型中，通过注入林格液增加IAP，通过测量膀胱、股静脉或下腔静脉的压力可可靠地估计IAP。间接估计为膀胱压力的IAP受膀胱内液体量的影响，液体量不应超过10 - 15 ml。股静脉血流减少反映了IAP升高时下腔静脉血流的变化。
