Haemoglobin level in Scottish intensive care patients--a national one day survey.

UNLABELLED: Objectives were to determine haemoglobin (Hb) levels present in patients and blood ordering habits of clinicians within Scottish Intensive Care Units (ICUs) on one typical day. A questionnaire survey (February 29 2000) was sent to all adult Scottish ICUs. All patients present in the responding adult ICUs in Scotland on the above date were included. MEASUREMENTS AND MAIN RESULTS: Nineteen (73%) of the 26 Scottish Adult Intensive Care Units (ICUs) responded to the questionnaire. Data were received from 78 patients, 8 (10%) received blood. Mean initial Hb was 102 g/l (range 63-138). Modal transfusion trigger haemoglobin was 80 g/l in 38% of subjects at first trigger, 100 g/l in 24% of cases. No intensive care unit allowed haemoglobin to fall below 70 g/l and no patients were transfused when measured Hb was greater than 100 g/l. The presence of ischaemic heart disease was the second most important trigger to transfuse after haemoglobin level. Modal transfusion was 2 units (n = 7). Only one patient received a single unit transfusion. CONCLUSIONS: Scottish ICUs maintain Hb between 70 and 100 g/l but clinicians are currently not consistent when ordering blood. More investigation is required to determine the optimal haemoglobin in our ICU population.

The 'transfusion trigger' in three large West of Scotland hospitals: medical staff questionnaire survey.

Efficient use of blood is desirable due to increased demand for blood, shortfall in donations, and the risk of mismatch transfusion accidents and transfusion-transmitted infections. We surveyed transfusion practice in three hospitals. Low haemoglobin was a feature in 91% of transfusion requests and is the commonest 'trigger' for transfusion. Forty-eight per cent of transfusions were initiated with the aim of restoring haemoglobin to 10 g dL(-1). Seventy-three per cent of transfusions were given when the patient's haemoglobin was between 7 and 10 g dL(-1). These figures suggest liberal blood use when compared with international practice. Major healthcare resource and patient safety implications result from this. Evidence-based guidelines issued at both local and national levels would be helpful.

Haemodynamic effects of diaspirin crosslinked haemoglobin (DCLHb) given before abdominal aortic aneurysm surgery.

We studied 34 patients undergoing elective repair of an abdominal aortic aneurysm under combined general anaesthesia and epidural block to evaluate the acute effects of diaspirin crosslinked haemoglobin (DCLHb) 50, 100 and 200 mg kg-1 i.v. Haemodynamic variables were measured continuously using pulmonary and radial artery catheters, and oxygen delivery and consumption were calculated at regular intervals. DCLHb was shown to be vasoactive, producing an increase in mean arterial pressure of approximately 25% with each dose, with small decreases in cardiac index and calculated oxygen delivery. These effects persisted beyond the end of infusion and provided a degree of cardiovascular stability during the operative procedure. The effects of DCLHb on oxygen consumption at these doses were minimal.

Effects of diaspirin cross-linked haemoglobin on post-traumatic cerebral perfusion pressure and blood flow in a rodent model of diffuse brain injury.

Diaspirin cross-linked haemoglobin (DCLHb) is a new oxygen carrying blood substitute with vasoactive properties. Vasoactive properties may be mediated via high affinity binding of nitric oxide by the haem moiety. Using a rodent model of head injury combined with ischaemia, we studied the effects of DCLHb on cerebral blood flow (CBF) and intracranial pressure (ICP). Twenty anaesthetized rats were allocated randomly to receive treatment with DCLHb 400 mg kg-1 i.v. or placebo (oncotically matched plasma protein substitute 4.5% i.v.). To produce diffusely increased ICP, after a severe weight drop injury, all animals underwent a 30-min period of bilateral carotid ligation combined with a period of induced hypotension. After reperfusion, DCLHb or placebo was infused and the animals instrumented for measurement of intraventricular ICP and CBF in the region of the sensorimotor cortex using the hydrogen clearance technique. Mean arterial pressure (MAP), ICP, cerebral perfusion pressure (CPP) (CPP = MAP - ICP) and CBF were measured 4 h after injury in all animals. DCLHb significantly reduced ICP from mean 13 (SEM 2) to 3 (1) mm Hg (P < 0.001), increased CPP from 52 (8) to 95 (6) mm Hg (P < 0.001) and increased CBF from 21 (2) to 29 (2) ml 100 g-1 min-1 (P = 0.032). We conclude that DCLHb improved CPP without a reduction in CBF in a rodent model of post-traumatic brain swelling.

A comparison of azapropazone and aspirin for pain relief following dental extractions.

Eighty patients received one of three treatments after elective dental surgery involving multiple extractions. Group A received aspirin 600 mg, group B azapropazone 300 mg and group C azapropazone 600 mg. All drugs were administered in a double-blind fashion. Quality of analgesia was unsatisfactory for all treatments; over 30% of patients required supplementary analgesia with an opioid. In addition there were a large number of withdrawals from the study. There were no significant differences in analgesic efficacy between groups.