CHANGES IN PLASMA-VOLUME IN IMMEDIATE PREOPERATIVE AND POSTOPERATIVE PERIODS IN PATIENTS WITH MAJOR GYNECOLOGIC SURGERY

Objective: Evaluating and comparing the repeatability of plasma volume (PV) measurement with the tracer indocyanine green (ICG) in immediate pre- and postoperative periods under stable anesthesia with other meas uring methods being generally accepted in clinical routine, such as me asurement of hematocrit (hct) and plasma protein concentration (prot). Design: Prospective study in 29 patients with ovarian tumors and 18 p atients with carcinomas of the cervix. Setting: Operating room of a gy necologic department of a university clinic. Participants: 47 patients with the above-mentioned gynecologic diseases. Interventions: Duplica te measurement of PV, hct, and prot with an interval of 40 min immedia tely before and after cytoreductive surgery during general anesthesia. Results: Standard deviations (of the differences of duplicate measure ments) of the measuring methods investigated were comparably low. With out infusion therapy and surgical blood loss there was preoperatively a significant decrease in hct and prot, reflecting a significant incre ase in PV, with total plasma protein mass (TPPM) remaining constant. I n patients with high PV and TPPM these parameters showed the tendency to decrease. Post-operatively no change in PV, hct, and prot was obser ved in patients with ovarian tumors. In patients with carcinomas of th e cervix a significant decrease in PV and TPPM was found. Conclusion: PV measurement with ICG is a precise measuring method compared with me asurement of hct and prot. However, PV is not a 'fixed' quantity but v aries due to physiological and pathophysiological stimuli. Preoperativ ely slight volume and protein shifts between interstitial and intravas cular spaces might be responses to induction of anesthesia and postope ratively could be caused by the surgical procedure and infusion therap y. These pathophysiological changes should be considered when judging the precision of PV measuring methods.