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Objective To observe the physiological and hepatic ischemia-reperfusion injury (ischemia reperfusion injury, IRI) state dynamics of controlling low central venous pressure (controlled low central venous pressure, CLCVP) on rabbit liver and kidney blood flow, liver and kidney function and body acid base equilibria to study CLCVP protective effect on the liver and kidney. Healthy adult 32 New Zealand white rabbits of either gender, weight 2.02 ± 0.07 kg, were randomly divided into four groups (each group, n = 8): control group (C group), the simple CLCVP group (L group), liver IRI group ( IR group) and CLCVP under liver IRI group (LIR group). The various groups of rabbits were confirmed by ear vein injection of 3% sodium pentobarbital 30 mg / kg, anesthesia, supine fixed. Tracheostomy mechanical ventilation, monitoring the blood pressure of the left common carotid artery, the right internal jugular vein to monitor central venous pressure (central venous pressure, CVP). The L group LIR the group establish CLCVP model: micro pump into the right femoral vein the nitroglycerin 3 0μg · kg -1 · min -1 (3.6 mg / ml), dopamine 30 4 0μg kg -1 · min -1 (4.8 mg / ml) in 5 min within the CVP dropped 4 5 cmH2O, and control of mean arterial blood pressure (mean arterial blood pressure, MAP) ≥ 80 mmHg. C group and IR group, intravenous infusion of normal saline. Then IR group and LIR group IRI model: along the rabbit right costal margin 1.5cm incision into the abdomen, separating the first hepatic portal vein, hepatic artery and common bile duct noninvasive arterial clip to a closed-door, 0.5 h after liver door. Anesthesia after 5 min (T 0 ) CLCVP model successfully (liver doors open) instantly (T 1 ) for 0.5 h (T ), 1 h (T 3 ), 2 h (T 4 ), 4 h (T 5 ), 6 h (T 6 ) point in time, color Doppler ultrasound monitoring group of liver and kidney blood vessel diameter, arterial mean blood flow velocity (mean-envelped blood flow 'velocity Vm), resistance index (resistance index, RI), and venous blood flow speed, collecting arterial blood gas analysis, lactate (lactic acid, LD), prothrombin time (prothrombin time, PT), activated partial thromboplastin time (activated partial thromboplastin time, APTT), Valley alanine aminotransferase (alanine transaminase, ALT), aspartate amino transferase (about aspartate transaminase, AST), creatinine (creatinine, Cr), urine output measured in T 6 point in time. Electron microscopy ultrastructural changes of liver and kidney. (1) liver and renal vascular color Doppler ultrasound monitoring: with group C ratio, the IR group hepatic artery Vm T 1 ~ 5 point in time slowed down, RI T 1 ~ 5 point in time were significantly increased; hepatic venous blood flow velocity T 5 6 point in time blood flow velocity increased (P lt; 0.05). LIR group hepatic artery Vm in the T 2 point in time slowed down, T 5 point in time to return to normal levels, RI T << / sub > sub> 1 ~ 2 point in time was significantly higher T 3 to return to normal levels; hepatic venous blood flow velocity in the T 1 ~ 6 point in time were significantly increased T 4 point in time of the peak (P lt; 0.05). With IR group than LIR group hepatic artery Vm in T << / sub> sub> 2 5 point in time significantly faster, RI T 3 to 4 significantly decreased the hepatic vein blood flow velocity in the T 1 ~ 6 point in time was significantly faster (P lt; 0.05). And group C ratio, IR group renal artery Vm and renal vein blood flow velocity, T << / sub> sub> 4 point in time slowed down (P lt; 0.05). IR group than, LIR group renal artery Vm and renal vein blood flow velocity in the T << / sub> sub> 4 point in time was significantly increased (P lt; 0.05). The remaining difference between the groups was not statistically significant (P gt; 0.05). (2) liver and kidney function: T and group C ratio, IR group 1 to 6 point in time ALT and AST , increasing high at T 5 point in time, reached the peak; T 1 to 6 point in time the PT and APTT value was significantly higher (P lt; 0.05). The LIR group T were significantly higher 6 point in time, T 3 point in time of the peak; T 1 to 6 point in time PT and APTT The value was significantly higher (P lt; 0.05). IR group than the the LIR set of ALT T 1,4 ~ 6 point in time significantly reduce AST T 1 ~ 6 point in time significantly reduced, PT and APT T T 1 ~ 6 point in time was significantly lower (P lt; 0.05). Than with the C group, IR group Cr was significantly higher in the T 1 ~ 6 point in time, reached the peak at T 5 point in time; urine output T 4 < / sub> 6 point in time significantly reduced (P lt; 0.05). LIR group Cr T 1 ~ 6 point in time are maintained at normal levels, urine volume (P lt; 0.05) decrease in T 4 point in time. The remaining difference between the groups was not statistically significant (P gt; 0.05). (3) acid-base balance: Group C than the pH of the IR group value T of 5 point in time significantly reduce (P lt; 0.05), LD value at T 1 ~ 6 point in time were significantly higher (P lt; 0.05). The LIR group pH value T 2 5 point in time are significantly reduced, LD T 1 ~ 6 point in time were significantly higher (P lt; 0.05 ). IR group than in, LIR group T 1 point in time difference was not statistically significant, but the first in the IR group returned to the the pH normal range, LD in T , ~~ 5 point in time are reduced. The other group between the pH and LD showed no statistical significance (P gt; 0.05). (4) electron microscopy of liver and kidney tissue ultrastructure markedly swollen: IR group liver cell mitochondria cristae marked hyperplasia of smooth endoplasmic reticulum, the perisinusoidal clearance surface microvilli obvious swelling, some vacuolization off into the hepatic blood sinuses, swelling of the liver sinusoidal endothelial cells necrosis, sinus wall destruction seen in hepatic blood sinuses neutrophil and lymphocyte infiltration; glomerular capillary expansion, podocyte foot processes with different degrees of integration or disappear . LIR group slightly hepatocyte mitochondrial swelling, no cristae, smooth endoplasmic reticulum hyperplasia, perisinusoidal gap surface microvilli slightly swollen liver sinusoidal endothelial cells slightly swollen sinus wall covering complete; glomerular capillary slightly expand, no foot process integration. Conclusion (1) in the physiological state CLCVP within 6 h of rabbit liver and kidney blood flow dynamics, liver and kidney function, the body's acid-base balance had no significant effect. (2) liver IRI cause the body's liver and kidney perfusion disorders, metabolic acidosis, liver and kidney dysfunction. (3) CLCVP reduce liver IRI after liver and kidney dysfunction, and to improve the acid-base balance, may be related to reduce blood deposition after liver IRI, improve liver and kidney perfusion and tissue oxygenation related.
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