Avtor/Urednik		Geršak, B; Trobec, R; Pšeničnik, M
Naslov		Loss of endothelium mediated vascular relaxation as a response to various clamping pressures: part 2. Direct measurements of clamping pressures and scanning electron microscope study
Tip		članek
Vir		Panminerva Med
Vol. in št.		Letnik 40, št. 4
Leto izdaje		1998
Obseg		str. 286-93
Jezik		eng
Abstrakt		We used novel equipment for measuring the direct tip preassure (P) of a clamp arm on the vessel wall and studied the relationship between endothelial ijuries and various clamping pressures. Methods. A strain gauge was appllied to the surgical clamparm and connected via amplifier to a 12-bit analogue-digitalconverter ona PC-MSDOS computer. In the on-line in vivo measurements on rat thoracic aorta a momentary peak clamping pressure (MPCP) as well as the lower stationary clamping pressure (SCP) was defined. Clamping forces of two clamps commonly used in cardiovascular microsurgery were tested in the experiment on rat thoracic aortas: clamp A had the tip pressure p=0.60 N/mm2 and clamb B p=5.16/mm2. After 15 minutes of occlusion, the thoracic aorta was excised and scanning electron microscopy studies for aortas clamped with clamp A and clamp B were performed. Results. Great endothelial lacerations with complete disruption of the endothelial layer in the rings clamped with the clamp B were seen, but no disruption in rings clamped with clamp A. Conclusions. The clamping vessel wall injuries, particulary in endothelial layers, depend on the momentary peak clamping pressure as well on the lower stationary clamping pressure.
Deskriptorji		AORTA, THORACIC CONSTRICTION ENDOTHELIUM, VASCULAR MICROSURGERY RATS, WISTAR MICROSCOPY, ELECTRON, SCANNING