Farklı Bakteri Türlerinin Farklı Ortam Koşullarında Kan Alkol Stabilitesine Etkisi

Abstract

Alcohol is an addictive substance that has been widely used in different societies for many years. Accurate and precise analysis of alcohol in body fluids, especially in blood, has an important place in forensic medicine applications. Regulations about collection and storage of blood samples have been published in order for this analysis to be accurate and standardized. However, from time to time, blood samples can be contaminated with different microorganisms or blood samples cannot be stored under appropriate temperature and / or storage conditions due to the lack of care during sampling by the blood collection personnel or lack of care during the preparation of the samples. For such reasons, there may be objections to judicial authorities. In our study, it was aimed to determine the effect of 3 different fermentation bacteria with high risk of contaminating blood samples on blood alcohol concentration and also how this effect changes under various tube and temperature conditions. For this purpose, 1 unit of whole blood sample taken from a healthy volunteer adult was filled in purple-capped EDTA (Ethylenediaminetetra-acetate) tubes and gray-capped NaF (sodium fluoride) tubes, and then pure ethyl alcohol was added to half of the blood tubes with a final ethyl alcohol concentration of 20 mg / dL and the other half to a final ethyl alcohol concentration of 50 mg / dL. Afterwards, Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli bacteria were added separately to these tubes with a final concentration of 106 CFU / ml. Some of the tubes did not contain any bacteria. Blood samples with known blood ethyl alcohol concentration, bacterial types and concentrations were kept under 3 different (4, 22 and 32°C) temperatures in order to be analyzed on the 1st, 3rd, 7th, 14th and 28th days. Ethanol concentrations of the samples were analyzed in HS-GC (Headspace-Gas Chromatography) device on the specified days. As a result of the analysis, whether the blood samples stored at 4 ° C are contaminated with bacteria or not, whether they are taken into tubes containing NaF or not, the blood ethyl alcohol concentration remains constant for a long time; When the ambient temperature increases, especially in samples contaminated with Escherichia coli bacteria, the blood ethanol concentration tends to increase during the first days, then decrease or remain constant; Samples contaminated with Staphylococcus epidermidis and Staphylococcus aureus or in sterile samples, when the temperature increased, the blood ethanol concentration tended to decrease. In addition, it was evaluated that the decrease in blood ethanol concentration increased in proportion to the temperature increase. In line with the findings determined in our study, blood samples to be studied should be taken into gray-capped blood tubes containing NaF, it would be correct to keep the blood samples to be analyzed at low temperatures during the transfer process and to analyze the ethanol concentration as quickly as possible. If there is a claim of bacterial contamination in cases whose blood ethyl alcohol level is analyzed, It is necessary to determine the probable type of bacteria in the samples. If these samples are contaminated with Escherichia coli, the result of blood ethyl alcohol is unreliable, medical and legal interpretation should be avoided, but if contaminated with Staphylococcus Aureus or Staphylococcus Epidermidis, the result of blood ethyl alcohol is reliable, medical and legal interpretation It was thought that it could be done.