The optimization of turnaround time for blood samples in an emergency clinical laboratory.

The University Medical Centre Ljublijana is a 3200-bed general hospital. A laboratory information system, developed to improve the reliability and usefulness of test results, was installed in the emergency laboratory in November 1994. At that time, all test requests received by the laboratory were treated as equally urgent, but in December 1994, a reorganisation took place, which involved the introduction of a priority system. We conducted a study in the period from November 1994 to September 1995. The turnaround time for blood analyses was evaluated by the method of case study. The influence of information technology and organisational changes on individual components of the turnaround time was assessed. This study has shown a positive effect of the recently introduced information technology and organisational changes on the turnaround time. The median turnaround time improved for all phases of the laboratory process. The greatest improvement occurred in validity check time.

Mildly elevated serum creatinine concentration correlates with the extent of coronary atherosclerosis.

Mildly elevated serum creatinine concentration was proposed to be a marker for increased risk of cardiovascular disease mortality. The aim of our prospective study was to evaluate a possible association between serum creatinine concentration and extent of coronary atherosclerosis together with conventional risk factors for atherosclerosis. Serum creatinine concentration was measured in 40 male patients without overt renal or ischemic renal disease (mean age 53 +/- 7 years) with stable or unstable angina undergoing routine coronary arteriography. The extent of coronary atherosclerosis was assessed by Gensini score. In univariate linear regression analysis Gensini score significantly correlated with serum concentrations of apolipoprotein AII (r=-0.3242, P<0.05) and creatinine (r=+0.3194, P<0.05), but not with serum concentrations of lipids (total, low- and high-density lipoprotein cholesterol, triglycerides), other apolipoproteins (apo B, apo AI), lipoprotein(a), autoantibodies to oxidatively modified low-density lipoprotein or age, weight and status of smoking, diabetes or hypertension. Multivariate linear regression analysis revealed that elevated serum creatinine was associated with the extent of coronary atherosclerosis independently of conventional risk factors for atherosclerosis. Mildly elevated serum creatinine was probably the marker of generalised vascular disease denoting early nephrovasculopathy in correlation with established atherosclerotic risk factors.

Comparison of laboratory parameters as risk factors for the presence and the extent of coronary or carotid atherosclerosis: the significance of apolipoprotein B to apolipoprotein all ratio.

We compared several "new" risk factors (autoantibodies to oxidatively modified low density lipoprotein (LDL), sialic acid content of LDL, bilirubin and C-reactive protein) with "conventional" risk factors (apolipoprotein (apo) AI, AII and B, lipoprotein(a), triglycerides, and total, LDL and high density lipoprotein (HDL) cholesterol) for the presence and the extent of coronary or carotid atherosclerosis. Forty male patients with angiographically proven coronary atherosclerosis and 31 male patients with ultrasound-proven extracranial carotid atherosclerosis were compared to 40 age matched (53+/-5 years) healthy males as control subjects, with negative parental history of atherosclerosis, no clinical signs of systemic or organ-related ischemic disease and normal extracranial carotid arteries. The apo B/apo All ratio most powerfully indicated the presence and the extent of coronary or carotid atherosclerosis. Elevated lipoprotein(a) contributed significant additional information in the assessment of the atherosclerotic risk. Increase in C-reactive protein indicated the presence (but not the extent) of coronary or carotid atherosclerosis with a similar power as lipoprotein(a). Decreased values of total bilirubin indicated the presence of atherosclerosis only in smokers. Autoantibodies to oxidatively modified LDL additionally described the atherosclerotic process, but were less important than apolipoproteins, lipoprotein(a), C-reactive protein or bilirubin. Sialic acid content of LDL added no information to the parameters discussed above. We demonstrated that in male patients apolipoproteins, especially the apo B/apo All ratio, were better indicators of the presence and the extent of coronary or carotid atherosclerosis than C-reactive protein, bilirubin, autoantibodies to oxidatively modified LDL or sialic acid content of LDL.