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BACKGROUND: Animal studies suggest less cardiovascular disturbance if the aorta and vena cava are occluded simultaneously. We set out to establish the effects of simultaneous clamping in humans, because oncologists suggested that perfusion for chemotherapy could be done under local anaesthesia without invasive haemodynamic monitoring. METHODS: We studied the cardiovascular effects of the onset and removal of simultaneous occlusion of the thoracic aorta and inferior vena cava, in seven ASA II patients. Two stop-flow catheters positioned in the aorta and in the inferior vena cava were inflated to allow hypoxic abdominal perfusion to treat pancreatic cancer. We measured the arterial pressure, heart rate (HR), right atrial pressure (RAP), pulmonary artery pressure (PAP), pulmonary artery wedge pressure (PAWP) and cardiac output (CO), and calculated systemic vascular resistance index (SVRi), pulmonary vascular resistance index (PVRi), left ventricular stroke work index (LVSWi) and right ventricular stroke work index (RVSWi). Three patients were studied with transoesophageal echocardiography. RESULTS: Six patients needed intravenous nitroprusside during the occlusion because mean arterial pressure (MAP) increased to more than 20% of baseline (SVRi increased by 87%). One minute after occlusion release, all patients had a 50% decrease in MAP, and mPAP increased by 50%. The procedure had severe cardiovascular effects, shown by a 100% increase in cardiac index at occlusion release with inc

There are few reports on anaesthesia for patients with Eisenmenger's syndrome requiring non-cardiac surgery and none of the use of xenon. We describe the use of xenon with a closed-circuit system in a patient with Eisenmenger's syndrome having a laparoscopic cholecystectomy.

The objectives of this thesis are to: 1. Compare the induced CDH in rats with the human situation and other available animal models. 2. Describe the morphological characteristics of the developing rat lung and diaphragm in congenital diaphragmatic hernia compared with controls. 3. Evaluate the suitability of this model in testing different ventilatory modes and the subsequent reaction of the CDH lung from a biochemical and histological point of view.

Patients with congenital diaphragmatic hernia (CDH) have unilateral or bilateral hypoplasia of the lungs including delayed maturation of the terminal air sacs. Because these lungs are highly susceptible to barotrauma and oxygen toxicity, even in full-term newborns, continued research into optimal ventilatory regimen is essential to improve survival rate and to prevent ongoing lung damage. Against this background, the effect of exogenous surfactant application is evaluated. In newborn rats, CDH was induced after a single dose of 2,4 dichloro-4'-nitrophenyl (Nitrofen) (400 mg/kg) on day 10 of gestation. The newborn rats were intubated immediately after hysterotomy, transferred to a heated multichambered body plethysmograph, and artificially ventilated. Inspiratory peak pressures were initially set at 17 cm H2O, with positive end-expiratory pressure at 0 cm H2O and FIO2at 1.0. The pressure was raised in steps of 5 cm H2O, from 5 to 30 cm H2O, to obtain pressure- volume diagrams at 0, 1, and 6 hours of artificial ventilation. These measurements were obtained in controls and in CDH rats with and without endotracheal installation of bovine surfactant (n = 4 to 10 in each group). Significant differences in lung volume between CDH and control rats were observed at all time-points. Surfactant application had a positive effect on lung volume, especially in control rats at t = 1 hour. No significant differences were observed between the CDH groups at t = 1 or t = 6 hours. In this animal model, the effect of artificial ventilation as well as the beneficial short-term effect of exogenous surfactant application have been evaluated. A continued positive effect on lung volume in CDH lungs could not be determined. Routine administration of exogenous surfactant in human CDH patients is not supported by these experimental results.

The effect of intratracheal surfactant instillation on pulmonary function in rats with Pneumocystis carinii pneumonia (PCP) was investigated. In those animals which developed PCP with severe respiratory failure after administration of cortisone acetate s. c. over 8-12 weeks, pulmonary function was improved by surfactant instillation. PaO2 values 30 min after surfactant instillation were significantly higher compared to pretreatment values and also compared to PaO2 values of rats 30 min after receiving saline (482.9 mmHg±44.7, 170.7 mmHg ±39.3 and 67.2 mmHg±17.4, respectively). Histological examination showed that alveoli of rats with PCP which received no exogenous surfactant are filled with foamy edema, whereas after exogenous surfactant alveoli are stabilized and well-aerated. These results indicate that exogenous surfactant may help patients with severe PCP to overcome an acute stage of respiratory distress.

16 patients underwent acute hypervolaemic haemodilution with dextran 40 and Ringers lactate, to see whether this procedure could avoid preoperative blood transfusion. Packed cell volume (PCV) and oxygen extraction decreased, and cardiac index and pulmonary wedge pressure increased, although end-systolic area was unchanged. PCV was not significantly different between patients who lost less than or greater than 20% of their initial blood volume. This preoperative manoeuvre, which reduces loss of red blood cells, allowed major surgery to be completed safely without blood transfusion.