BJA Advance Access originally published online on March 10, 2006
British Journal of Anaesthesia 2006 96(5):563-568; doi:10.1093/bja/ael045
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Haemodynamic, acid–base and blood volume changes during prolonged low pressure pneumoperitoneum in rabbits
1 Medizinische Hochschule Hannover, Zentrum Anästhesiologie OE 8050, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany
2 Klinik für Anästhesiologie und Intensivtherapie, Klinikum der Friedrich-Schiller-Universität Jena Erlanger Allee 101, D-07747 Jena, Germany
3 Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1 D-30625 Hannover, Germany
4 Medizinische Hochschule Hannover, Biometrie OE 8410, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany
5 Medizinische Hochschule Hannover, Kinderchirurgie OE 6760, Carl-Neuberg-Strasse 1, D-30625 Hannover, Germany
*Corresponding author. E-mail suempelmann.robert{at}mh-hannover.de
Background. The anaesthetic management of small infants during advanced laparoscopic surgery can be complicated by the major pathophysiological effects of increased intra-abdominal pressure. In this study haemodynamic, acid–base and blood volume changes were investigated during pneumoperitoneum in a small animal model.
Methods. Ten fasted, anaesthetized, mechanically ventilated and multi-catheterized New Zealand rabbits were randomized to carbon dioxide pneumoperitoneum (PP, duration 210 min, pressure 8 mm Hg) or control group. Cardiac index was determined using trans-cardiopulmonary thermodilution and total blood volume was measured by thermal-dye dilution with indocyanine green using a fibreoptic monitor system.
Results. In PP cardiac index (CI), central venous oxygen saturation (SCVO2), total blood volume (TBV) and base excess (BE) decreased significantly during the study whereas all variables remained constant in the control group. After release of PP the measured variables did not return to baseline within 30 min [PP, baseline vs study end: CI 108 (22) vs 85 (14) ml kg–1 min–1, SCVO2 81.4 (8.9) vs 56.7 (9.8)%, TBV 318 (69) vs 181 (54) ml, BE –1.9 (2.7) vs –8.7 (1.8) mmol litre–1; P<0.01].
Conclusion. Our animal model suggests that a decrease in CI, metabolic acidosis and hypovolaemia could occur after prolonged low pressure pneumoperitoneum in small infants, which is possibly not detectable by the standard monitor setting. Therefore, the routine use of an extended monitoring including measurement of central venous oxygen saturation and acid–base parameters should be considered during and soon after operation, when pneumoperitoneum will last longer than 2 h.