MINIMALLY INVASIVE SURGERY - ANESTHESIOLO GICAL PECULIARITIES

Laparascopic operative techniques (pneumoperitoneum, patient positioni ng) tend to burden the cardiovascular system to a degree which, in the individual case is unprectable. The indication for minimally invasive surgery (MIS) is increasingly being established in patients who belon g to an older age group and thus have a higher incidence of concomitan t diseases. Furthermore, the surgical spectrum has expanded to include interventions which may be considerably longer in duration than gynae cological laparoscopic procedures. Operating times of up to 60 minutes are associated with a decrease in cardiac index (CI) the degree of wh ich varies with the volume situation and individual myocardial functio n. Pulmonary gas exchange does not appear to be impaired During the pn eumoperitoneum, functional residual capacity and compliance are marked ly reduced. The preferential use of a given anaesthetic procedure is n ot supported by the results of investigations. The particular circumst ances associated with MIS (extreme positioning, temporary hypercapnia, changes in the cardiovascular system), suggest that insufflation anae sthesia with controlled ventilation represents the most rational alter native. The ''gentle'' nature of minimally invasive surgery in terms o f postoperative pulmonary function, and the cosmetic effect, are undis puted. However the stress on the cardiovascular system in the intra-op erative phase, which increases with the duration of the procedure, may lead to an increase in intra-operative morbidity in patients with the relevant predisposition.