The multimodal water jet dissector--a technology for laparoscopic liver surgery.

UNLABELLED: In order to avoid laparotomy in patients with superficially and/or anatomically favourably located liver lesions, the feasibility of laparoscopic liver resection using an aqua jet was evaluated in 6 pigs. For this purpose a commercially available water jet dissector was adapted for laparoscopic use and modified to a multifunctional device providing aqua jet, suction and cautery. To improve laparoscopic vision during jet activity a hydrolaparoscope was used. The left lateral lobe was resected using clips for haemostasis only. RESULTS: All animals (34-55 kg, average 41 kg) survived the procedure. The blood loss at operation consisted of 225 ml (50-600 ml), the haematocrit 3.3% (1-8%). No bleeding or other complications were encountered postoperatively. The average weight of the specimens was 201 g (120-289 g). CONCLUSIONS: Laparoscopic liver resection using an aqua jet is feasible. Safe haemostasis can be achieved with clips if the vessels are entirely freed with the jet before clipping.

Hemodilution tolerance in elderly patients without known cardiac disease.

Hemodilution tolerance is not well defined in elderly patients. In 20 patients older than 65 yr and free from known cardiovascular disease, hemodynamic variables, ST segment deviation, and O2 consumption were determined prior to and after 6 and after 12 mL/kg isovolemic exchange of blood for 6% hydroxyethyl starch. The mean age of the patients was 76 +/- 2 yr (mean +/- SEM, range 66-88 yr). During hemodilution, hemoglobin decreased from 11.6 +/- 0.4 to 8.8 +/- 0.3 g/dL (P < 0.05). With stable filling pressures, cardiac index increased from 2.02 +/- 0.11 to 2.19 +/- 0.10 L.min-1.m-2 (P < 0.05) while systemic vascular resistance decreased from 1796 +/- 136 to 1568 +/- 126 dynes.s.cm-5 (P < 0.05) and O2 extraction increased from 28.0% +/- 0.9% to 33.0% +/- 0.8% (P < 0.05) resulting in a stable O2 consumption during hemodilution. No alterations in ST segments were observed in lead II during hemodilution. In lead V5, ST segment deviation became slightly less negative during hemodilution from -0.03 +/- 0.01 to -0.02 +/- 0.01 mV (P < 0.05). The moderate decrease in hemoglobin was fully compensated by both an increase in cardiac index and in O2 extraction. Electrocardiographic signs of myocardial ischemia were not observed in this population. In conclusion, isovolemic hemodilution to a hemoglobin value of 8.8 +/- 0.3 g/dL is well tolerated in elderly patients free from known cardiac disease at the ages of 65-88 yr.