0016-5107/95/4102-012153.00 + 0 GASTROINTESTINAL ENDOSCOPY Copyright | 1995 by the American Society for Gastrointestinal Endoscopy Hemodynamic effects of prolonged abdominal insufflation for laparoscopic procedures Ursula Windberger, DVM, Helga Siegl, DVM, Jim G. Ferguson, DVM, Heinrich Schima, PhD Reinhold FiJgger, MD, Friedrich Herbst, MD, Michael Schemper, PhD, Udo Losert, DVM Vienna, Austria Abdominal insufflation for laparoscopic procedures leads to numerous hemodynamic effects. We focused on blood flow distribution and arterial and venous pressure changes during CO2 insufflation at an intra-abdominal pressure of 12 mm Hg. Three segments of the vascular system were inves- tigated (intrathoracic, cranial extrathoracic, caudal extrathoracic) in supine animals at insufflation, during a 90-minute period of pneumoperito- neum, and at desufflation. Except for instrumentation of the animals, no further surgery was performed. At insufflation (+5 minutes), cardiac out- put increased from 2.7_ 0.5 to 3.3_ 1.1 I./min while heart rate de- creased from 138 • 26 to 128 • 17 beats per minute. Increases in jugu- lar venous (from 6 • 1 to 11 • 4 mm Hg) and atrial (right, from 7 • 1 to 12 • 3; left, from 12 • 4 to 17 __ 5 mm Hg) pressures occurred uniformly during inspiration. The great variance in atrial pressures during ventilation was not associated with changes in stroke volume, as the effective transmu- ral filling pressures remained nearly constant. The increase in femoral ven- ous pressure occurring during both inspiration and expiration (from 10 __ 2 to 18 • 4 mm Hg) exceeded the increase in right atrial and jugular ven- ous pressures during inspiration. Parallel increases were noted in arter- ial pressures (carotid, from 119 __ 15 to 129 • 9; femoral, from 122 • 16 to 133 _ 10 mm Hg), left ventricular pressure (from 133 _ 17 to 143 • 10 rnm Hg), and carotid and femoral flow (carotid, from 174 • 71 to 195 • 70; femoral, from 66 • 25 to 73 _+ 40 (NS) mL/min). During pneumoperito- neum, arterial pressures, and flows, dLVP/dt, and tension time index decreased continuously below baseline while venous and atrial pressures were maintained. Heart rate increased at pneumoperitoneum. At desufflation, atrial and venous pressures decreased as they were directly related to me- chanical strain, whereas the blood flows increased again. Abdominal insuf- flation was associated with increased cardiac output, cardiac contractility, and arterial pressures, at least initially. Although caudal venous resistance increased, blood flow distribution was not affected. (Gastrointest Endosc 1995;41:121-9.) Received September 2, 1992. For revision November 11, 1992. Accepted May 11, 1994. From the Center for Biomedical Research, Ludwig Boltzmann Institute for Cardiosurgical Research; Bioengineering Lab- oratory, Second Department of Surgery; First Department of Surgery; and Section of Clinical Biometrics, Department of Medical Computer Sciences, University of Vienna, Austria; and the Department of Veterinary Anaesthesiology, Radi- ology and Surgery, University of Saskatchewan, Saskatoon, SK, Canada. Reprint requests: Ursula Windberger, DVM, Center for Biomedi- cal Research, University of Vienna, General Hospital, Ebene 1Q, Wi~hringergi~rtel 18-20, A-1090 Vienna, Austria. 37/1/58360 VOLUME 41, NO. 2, 1995 GASTROINTESTINAL ENDOSCOPY 121