Cardiovascular effects of simultaneous occlusion of the inferior vena cava and aorta in patients treated with hypoxic abdominal perfusion for chemotherapy

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 increases in left and right ventricular stroke work indices of 75% and 147%. Left ventricular wall motion abnormalities were seen on transoesophageal echocardiography. Conclusions. Serious haemodynamic changes occur during simultaneous occlusion of the thoracic aorta and inferior vena cava, which may need invasive haemodynamic monitoring.