- Email: [email protected]
Pulmonary function in advanced pulmonary hypertension
LITERATURE REVIEW
MK 422. Animals on left heart bypass maintained a urine output of 4.68 _+ 0.76 mL/kg/h and renal blood flow (RBF) of 60% of control. However, after 30 minutes of reperfusion, urine output was decreased, RBF was 70% of control, and glomerular filtration rate (GFR) was 50% of control in animals undergoing simple aortic clamping. The enalaprilat group demonstrated normal urine output, RBF at 113% of control, and glomerular GRF of 84% of control. The dogs on left heart bypass had GFR and RBF at 54% of control, although urine output was unchanged from control. These results suggest that in this canine model of thoracic aortic occlusion, converting enzyme inhibition reduces the alterations in renal hemodynamics attributable to the reninangiotensin system.
Burke CM, Glanville AR, Morris AJR, et ah Pulmonary function in advanced pulmonary hypertension. Thorax 42:131-135, 1987 Advanced pulmonary vascular disease resulting from either Eisenmenger's physiology or primary pulmonary hypertension is associated with decreased pulmonary function. In a group of 33 patients being considered for cardiopulmonary transplantation, airway obstruction was present, lung volumes were decreased, and gas transfer was reduced. Total lung capacity was 81.5% of predicted, while function residual capacity was 89.2% of predicted. Dynamic variables including FVC, FEVI, and FEF~5.75 were also reduced. Alveolar hyperventilation was present in all patients. Alterations in flow did not appear to be volume related. Gas transfer was 78% of predicted (significantly reduced). The hypoxemia present was disproportionate to the mechanical airway obstruction. A possible mechanism for these findings is mechanical coupling of the vascular and air spaces, although this study does not provide specific evidence for this hypothesis.
Martin JF, Daniel TD, Trowbridge EA: Acute and chronic changes in platelet volume and count after cardiopulmonary bypass-induced thrombocytopenia in man. Thromb Haemost 57:55-58, 1987 Although acute changes in platelet count and volume in patients undergoing open heart surgery are well known, the long-term effects have not been extensively studied. In this series of 26 patients (6 aortic valve replacement, 8 mitral
493
valve replacement, and 12 coronary bypass grafting), platelet count and volume were serially evaluated for 48 days. However, the majority of patients were studied for only one week, and long-term studies were obtained in only five to seven patients. Valve replacement patients received porcine heterografts. Intraoperative blood loss was limited by the use of cardiotomy suction so that no blood was transfused. A Shiley 100-bubble oxygenator was used in all cases. As expected, the platelet count decreased immediately postoperatively without alteration of platelet volume. There was a further decrease in platelet count through the third postoperative day. An increase in platelet volume accompanied the decreased platelet count. After day 3, there was an increase in platelet count, reaching a maximum at 14 to 17 days after surgery, associated with decreased platelet volume. Although hemodilution might explain the immediate postoperative decrease in platelet count, it does not explain the decrease on the third postoperative day. Unlike previous investigators using different methodology, preferential removal or sequestration of larger, more reactive platelets did not occur during cardiopulmonary bypass. The increased platelet count and decreased platelet volume seen in the late postoperative period that exceeded values from the preoperative period suggests that pre-existing platelet abnormalities were normalized by the operative procedure. ACKNOWLEDGMENT
The papers reviewed for this issue included those published in the following journals: Acta Anaesthesia Scan-
dinavica, American Heart Journal, American Journal of Cardiology, American Review of Respiratory Diseases, Anaesthesia, Anaesthesia and Analgesia, Anesthesiology, Annals of Thoracic Surgery, Angiology, Archives of Internal Medicine, British Journal of Anaesthesia, Canadian Anaesthetists Society Journal, Circulation, Circulation Research, Critical Care Medicine, European Heart Journal, Hypertension, International Journal of Cardiology, Journal of the American College of Cardiology, Journal of the American Medical Association, Journal of Applied Physiology, Journal of Critical Care, Journal of Molecular and Cellular Cardiology, Journal of Pharmacology and Experimental Therapeutics, Journal of Thoracic and Cardiovascular Surgery, Journal of Vascular Surgery, New England Journal of Medicine, Perfusion, Thorax, Thrombosis and Haemostasis, Transplantation, and Vascular Surgery.
MK 422. Animals on left heart bypass maintained a urine output of 4.68 _+ 0.76 mL/kg/h and renal blood flow (RBF) of 60% of control. However, after 30 minutes of reperfusion, urine output was decreased, RBF was 70% of control, and glomerular filtration rate (GFR) was 50% of control in animals undergoing simple aortic clamping. The enalaprilat group demonstrated normal urine output, RBF at 113% of control, and glomerular GRF of 84% of control. The dogs on left heart bypass had GFR and RBF at 54% of control, although urine output was unchanged from control. These results suggest that in this canine model of thoracic aortic occlusion, converting enzyme inhibition reduces the alterations in renal hemodynamics attributable to the reninangiotensin system.
Burke CM, Glanville AR, Morris AJR, et ah Pulmonary function in advanced pulmonary hypertension. Thorax 42:131-135, 1987 Advanced pulmonary vascular disease resulting from either Eisenmenger's physiology or primary pulmonary hypertension is associated with decreased pulmonary function. In a group of 33 patients being considered for cardiopulmonary transplantation, airway obstruction was present, lung volumes were decreased, and gas transfer was reduced. Total lung capacity was 81.5% of predicted, while function residual capacity was 89.2% of predicted. Dynamic variables including FVC, FEVI, and FEF~5.75 were also reduced. Alveolar hyperventilation was present in all patients. Alterations in flow did not appear to be volume related. Gas transfer was 78% of predicted (significantly reduced). The hypoxemia present was disproportionate to the mechanical airway obstruction. A possible mechanism for these findings is mechanical coupling of the vascular and air spaces, although this study does not provide specific evidence for this hypothesis.
Martin JF, Daniel TD, Trowbridge EA: Acute and chronic changes in platelet volume and count after cardiopulmonary bypass-induced thrombocytopenia in man. Thromb Haemost 57:55-58, 1987 Although acute changes in platelet count and volume in patients undergoing open heart surgery are well known, the long-term effects have not been extensively studied. In this series of 26 patients (6 aortic valve replacement, 8 mitral
493
valve replacement, and 12 coronary bypass grafting), platelet count and volume were serially evaluated for 48 days. However, the majority of patients were studied for only one week, and long-term studies were obtained in only five to seven patients. Valve replacement patients received porcine heterografts. Intraoperative blood loss was limited by the use of cardiotomy suction so that no blood was transfused. A Shiley 100-bubble oxygenator was used in all cases. As expected, the platelet count decreased immediately postoperatively without alteration of platelet volume. There was a further decrease in platelet count through the third postoperative day. An increase in platelet volume accompanied the decreased platelet count. After day 3, there was an increase in platelet count, reaching a maximum at 14 to 17 days after surgery, associated with decreased platelet volume. Although hemodilution might explain the immediate postoperative decrease in platelet count, it does not explain the decrease on the third postoperative day. Unlike previous investigators using different methodology, preferential removal or sequestration of larger, more reactive platelets did not occur during cardiopulmonary bypass. The increased platelet count and decreased platelet volume seen in the late postoperative period that exceeded values from the preoperative period suggests that pre-existing platelet abnormalities were normalized by the operative procedure. ACKNOWLEDGMENT
The papers reviewed for this issue included those published in the following journals: Acta Anaesthesia Scan-
dinavica, American Heart Journal, American Journal of Cardiology, American Review of Respiratory Diseases, Anaesthesia, Anaesthesia and Analgesia, Anesthesiology, Annals of Thoracic Surgery, Angiology, Archives of Internal Medicine, British Journal of Anaesthesia, Canadian Anaesthetists Society Journal, Circulation, Circulation Research, Critical Care Medicine, European Heart Journal, Hypertension, International Journal of Cardiology, Journal of the American College of Cardiology, Journal of the American Medical Association, Journal of Applied Physiology, Journal of Critical Care, Journal of Molecular and Cellular Cardiology, Journal of Pharmacology and Experimental Therapeutics, Journal of Thoracic and Cardiovascular Surgery, Journal of Vascular Surgery, New England Journal of Medicine, Perfusion, Thorax, Thrombosis and Haemostasis, Transplantation, and Vascular Surgery.