Blood loss during surgery

Reflections on pandemics and the 60th anniversary of the University of New South Wales Medical School

In March 1961 the University of New South Wales enrolled the first students into the new faculty of medicine that is now ranked 4th in Australia and 59th in the world. The author was fortunate to be a member of that pioneering group and looks back in gratitude to all the visionary and committed academics and mentors, who made this happen. Many of the foundation academics were fellows of the Royal Australasian College of Physicians, with two becoming University of New South Wales deans of medicine. One-quarter of the foundation year's graduates became fellows of the college and the first PhD medical graduate, Professor John Chalmers AC, became president of the college.

Blood Loss Associated with Uncemented Total Hip Replacement: Hypotension Does not Affect Blood Loss

Twenty-seven patients who were moderately hypotensive during uncemented total hip replacement were compared with a group of normotensive patients. There was no statistical difference (P < 0.05) in blood loss measured at time of operation, following operation or in the calculated loss. Hypotension, which is known to be dangerous in the elderly, conferred no benefit and should be avoided.

Intraoperative blood loss during radical retropubic prostatectomy: epidural versus general anesthesia

OBJECTIVES

There are conflicting reports on the influence of different anesthetic techniques, such as regional versus general anesthesia, on intraoperative blood loss. The purpose of this study was to elucidate the effects of anesthetic technique on intraoperative blood loss in men undergoing radical retropubic prostatectomy (RRP).

METHODS

One hundred patients undergoing RRP for prostate cancer were randomly assigned to receive either epidural anesthesia (EA), combined epidural and general anesthesia (EG), or general anesthesia alone (GA). Intraoperative blood loss was calculated by using a formula that accounted for the volume and hematocrit of the fluid suctioned from the surgical field, blood absorbed on surgical pads, and the patient's hematocrit.

RESULTS

Mean blood loss in the EA group (1490 +/- 90 mL; mean +/- SEM) was significantly less than mean blood loss in both the EG group (1810 +/- 100 mL) and the GA group (1940 +/- 130 mL) (P = 0.01). Blood loss was not different between the EG and the GA groups (P = 0.7). Significantly less blood was transfused during surgery in the EA group (730 +/- 50 mL) compared with the EG (960 +/- 60 mL) and GA (950 +/- 70 mL) groups (P = 0.02).

CONCLUSIONS

Similar blood loss in patients receiving general anesthesia, either alone or when combined with epidural anesthesia, implies that epidural anesthesia did not reduce bleeding, but, rather, that general anesthesia increased blood loss.

Anaesthesia and blood loss in total hip replacement

Twenty-seven consecutive patients scheduled for total hip replacement were randomly divided into three groups. The first group had their operations under epidural analgesia, the second whilst breathing halothane spontaneously and patients in the third group were anaesthetised using a modified neuroleptoanaesthetic (NLA) technique. Blood lost during the operation was measured by a colorimetric technique. Closed suction drains were used and all blood lost after the operation collected for measurement. Deliberate hypotensive techniques were not employed. The mean operative blood loss of patients who had their operations under epidural anaesthesia was significantly less than that of patients in the other two groups, being 341-6 +/- 59-1 ml (s.e.m.) for the epidural group, 648-4 +/- 58-3 ml (s.e.m.) for the halothane group and 744 +/- 98-9 ml (s.e.m.) for the NLA group. There was no significant difference in the amounts of blood collected by closed suction drainage in any of the three groups and the mean values for total overall blood loss incurred by procedure were 734-1 +/- 40-7 ml (s.e.m.) for the epidural group, 986-3 +/- 94-9 ml (s.e.m.) for the halothane group and 1168-4 +/- 126 ml (s.e.m.) for the NLA group. In this series only 3 of 10 patients (30%) who had their operation under epidural anaesthesia required transfusion with whole blood, compared with 7 of 9 (78%) in the halothane group, and 7 of 8 (87-5%) in the neuroleptoanalgesia group. From this series it is evident that the need for transfusion of whole blood in total hip replacement can be significantly reduced by the use of epidural analgesia.

Blood Volume in Malignant Disease: Case Studies in 86 Females1

The problem of blood replacement in the individual cancer patient remains unanswered. On present evidence, such a patient must be assumed to be drawn from a population with a mean total blood volume and mean red-cell volume below normal and thus must be assumed to have a better-than-even chance of having a depleted volume. However, it does not necessarily follow that transfusion is necessary; this should ideally be assessed by blood volume determination in each individual case.