Transoesophageal echocardiographic assessment of haemodynamic changes during laparoscopic herniorrhaphy in small children.

Laparoscopic techniques for surgery are gradually becoming established in paediatric surgery. Technical aspects, such as the maximum safe gas insufflation pressure, are still open to discussion. We used transoesophageal echocardiography to study the haemodynamic changes in eight small children undergoing laparoscopic herniorrhaphy, with two different levels of intra-abdominal pressure (IAP), 6 and 12 mm Hg. End-tidal carbon dioxide tension was maintained constant at 4.3-4.7 kPa. After baseline measurements, an IAP of 12 mm Hg was applied for 10 min. Next, IAP was decreased to 6 mm Hg, followed by a second period of 12 mm Hg. Haemodynamic measurements were obtained at each stage. A further measurement was obtained 10 min after abdominal deflation at the end of surgery while anaesthesia was unchanged. Cardiac index (CI) decreased significantly only after the first 12 mm Hg level of IAP. The subsequent decrease in IAP to 6 mm Hg caused return of CI to baseline levels. The second increase in IAP did not cause any reduction in CI. The initial reduction in CI, although statistically significant, did not appear to be clinically important. We conclude that an IAP of up to 12 mm Hg appeared to be safe in healthy small children undergoing laparoscopic herniorrhaphy.