Operations in the pleural cavity are connected with circulatory changes in pulmonary circulation and general changes of hemodynamics. These changes are influenced by the position of patient’s body on the operation table and by the introduction of artificial pneumothorax. Thoracoscopy is an advanced surgical approach in thoracic surgery, but its hemodynamic effect is still not known. The aim of the present study was to compare the hemodynamic response to surgeries carried out by open (thoracotomy - TT) and closed (thoracoscopy - TS) surgical approach. Thirty-eight patients have been monitored throughout the operation - from the introduction of anesthesia to completing the surgery. Monitored parameters were systolic blood pressure (BPs), diastolic blood pressure (BPd), O2 saturation (SaO2), systolic blood pressure in pulmonary artery (BPPAs), diastolic blood pressure in pulmonary artery (BPPAd), wedge pressure (PW), central venous pressure in right atrium (CVP), cardiac output (CO) and total peripheral resistance (TPR). No significant difference has been found in hemodynamic response between TT and TS groups. Significant changes of hemodynamic parameters occurring during the whole surgical procedure were detected in both technical approaches. The most prominent changes were found after the position of patients was changed to the hip position (significantly decreased BPs, BPd, MAP, SaO2 and BPPAs) and 5 min after the pneumothorax was established (restoration of the cardiac output to the initial value and significant decrease of the TPR). It can be concluded that the thoracoscopy causes almost identical hemodynamic changes like the thoracotomy., S. Trča ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The most dramatic changes in pulmonary circulation occur at the time of birth. We hypothesized that some of the effects of perinatal hypoxia on pulmonary vessels are permanent. We studied the consequences of perinatal exposure to hypoxia (12 % O2 one week before and one week after birth) in isolated lungs of adult male rats (~12 weeks old) perfused with homologous blood. Perfusion pressure-flow relationship was tilted towards lower pressures in the perinatally hypoxic as compared to the control, perinatally normoxic rats. A non-linear, distensible vessel model analysis revealed that this was due to increased vascular distensibility in perinatally hypoxic rats (4.1±0.6 %/mm Hg vs. 2.3±0.4 %/mm Hg in controls, P = 0.03). Vascular occlusion techniques showed that lungs of the perinatally hypoxic rats had lower pressures at both the pre-capillary and post-capillary level. To assess its role, basal vascular tone was eliminated by a high dose of sodium nitroprusside (20 µM). This reduced perfusion pressures only in the lungs of rats born in hypoxia, indicating that perinatal hypoxia leads to a permanent increase in the basal tone of the pulmonary vessels. Pulmonary vasoconstrictor reactivity to angiotensin II (0.1-0.5 µg) was reduced in rats with the history of perinatal hypoxia. These data show that perinatal hypoxia has permanent effects on the pulmonary circulation that may be beneficial and perhaps serve to offset the previously described adverse consequences., V. Hampl, J. Bíbová, J. Herget., and Obsahuje bibliografii