Continuous haemodynamic monitoring using transoesophageal Doppler during acute normovolaemic haemodilution in patients with coronary artery disease

Abstract

SummaryTransoesophageal Doppler monitoring allows non-invasive assessment of stroke volume. We studied haemodynamic changes during acute normovolemic haemodilution (ANH) in anaesthetised patients with coronary artery disease. Twenty patients were randomly assigned to either ANH or a control group. During ANH, a mean (SD) blood volume of 15.3 (3.4) ml.kg )1 was withdrawn decreasing systemic oxygen delivery from 12.7 (3.3) to 9.3 (1.8) ml.kg.min )1 (p < 0.001).In the control group, haemodynamic data remained unchanged, whereas in the ANH group, stroke volume and central venous pressure increased significantly (mean = +21 ml [95% CI: 18-25 ml.min A reduced viscosity associated with ANH resulted in improved venous return, higher cardiac preload and increased cardiac output. In summary, this study demonstrated that ANH to a haemoglobin value of 8.6 g.dl )1 was well tolerated in patients with coronary artery disease.

Pride and prejudice

“…This may follow both acute or chronic opioid intake. Acutely, it usually manifests as a part of a postoperative ileus that itself may be attributed to surgical stress, or to alterations in fluid and electrolyte balance [1]. In…”

“…A quick scan through the contents pages from 2004 reveals an eclectic mixture of areas of patient care and basic science where anaesthetists have made, and continue to make, their mark. In our own specialist fields, we have designed, developed and tested new technologies to improve safety and quality of care [1,2]. We have become more adept at managing difficult, life-threatening airway problems [3,4].…”

Acute Normovolemic Hemodilution in Cardiac Surgery

“…34 In patients scheduled for CABG surgery, several studies demonstrated that moderate ANH (target hematocrit value 27-33%) is well tolerated, provided that determinant of systemic and myocardial oxygen demand are well controlled. [35][36][37] In these patients, cardiac medication, especially β-blockers, was maintained until the day of surgery and ANH was performed under anesthesia to avoid the increase in heart rate usually observed in awake patients in these circumstances. 11 However, any increase in myocardial O 2 demand in these conditions could be associated with the development of myocardial ischemia and cardiac dysfunction.…”

Impact of Acute Normovolemic Hemodilution in Organ and Cell Structure

“…A study demonstrated that ANH to a mean hemoglobin value of 8.6 g/dL was well tolerated in anesthetized patients with coronary artery disease who were receiving beta-blockers. These patients presented no ECG abnormalities or hemodynamic instability (Licker et al, 2004). A recent study comparing transfusion strategies in 512 patients, submitted to cardiac surgery, found that a restrictive strategy, defined as a transfusion performed when the hematocrit reached values of  24%, was as safe as the liberal strategy, defined as hematocrit  30%.…”