Anesthesia and analgesia
-
Anesthesia and analgesia · Apr 2002
Does indocyanine green accurately measure plasma volume early after cardiac surgery?
Potential overestimation of plasma volume (PV) determination by the conventional indocyanine green (ICG) dilution method (PV-ICG) can occur when generalized capillary protein leakage is present, because ICG binds to proteins. We recently reported that this overestimation can be recognized by simultaneous measurement of the initial distribution volume of glucose (IDVG). We examined whether overestimation of PV-ICG and further ICG-pulse dye densitometry-derived plasma volume (PV-PDD) can occur early after cardiac surgery by using the PV-ICG/IDVG ratio as an indicator. Possible overestimation was defined as a ratio higher than 0.45. Twenty-four consecutive postcardiac surgical patients were enrolled. PV-ICG, PV-PDD, and IDVG were calculated simultaneously after admission to the intensive care unit and on the first postoperative day. The mean +/- SD PV-ICG/IDVG ratio for 47 recordings was 0.38 +/- 0.05. Four had a PV-ICG/IDVG ratio higher than 0.45, and the highest was 0.48. The mean PV-PDD/IDVG ratio for a total of 47 recordings was 0.39 +/- 0.10. There were extremely high or low ratios observed in PV-PDD determinations, but they were not observed in PV-ICG determinations. Results suggest that most of the PV-ICG measurements are accurate, but inaccuracy of PV-PDD can occur early after cardiac surgery. ⋯ Overestimation of indocyanine green-derived plasma volume can occur in the presence of generalized capillary protein leakage. This overestimation was examined early after cardiac surgery by using the simultaneous measurement of the initial distribution volume of glucose. We suggest that overestimation of the traditional dye dilution method is negligible, but apparent over- or underestimation of pulse dye densitometry-derived plasma volume cannot be negligible.
-
Anesthesia and analgesia · Apr 2002
The reduction of preoperative autologous blood donation for primary total hip or knee arthroplasty: the effect on subsequent transfusion rates.
We conducted this quality assurance observational study to examine the effects of a change in policy regarding preoperative autologous blood donation (PABD) and indications for perioperative blood transfusion in patients undergoing primary total hip or knee arthroplasty. Two successive time periods, each including 182 successive patients treated by the same medical team and with standardized anesthesia, were compared. The first study had the following standard transfusion policy: 3 U of PABD collected (n = 119) and liberal autologous transfusion (AT). The second study introduced a specific indication for PABD, on the basis of estimated red blood cell reserve and a life expectancy of more than 10 years; 2 U of PABD was collected (n = 81), and criteria were identical for AT and allogeneic transfusion. We mainly compared the incidence of AT; allogeneic and overall transfusions; the inclusion, admission, and discharge hematocrit values; and the wastage of PABD units. This novel policy increased the number of untransfused patients by a factor of 10 (5.5% vs 56.6%) (P < 0.0001), decreased the number of PABD patients by 30% with a 2.4-fold reduction in AT (30% vs 80%) (P < 0.0001), and did not change allogeneic requirements (13% vs 15%). Although fewer autologous units were collected (172 vs 426), the wastage was higher in Study 2 (46% vs 12%) (P < 0.0001). We conclude that incorporation of patients' individual factors improves the efficiency of transfusion for total hip and total knee arthroplasty surgeries. ⋯ We compared two transfusion policies for primary total hip or knee arthroplasties: first, a standard preoperative autologous donation with a liberal autologous transfusion policy; and second, a more restrictive indication for autologous donation that was based on patients' individual factors, with identical criteria for autologous and allogeneic transfusion. We found that this change of policy reduced autologous donation and transfusion with no increase in allogeneic transfusion.