الفهرس 
Bacterial contamination of the transfused blood and blood componentsOnly 14 pages are availabe for public view
 |  | from | 70 |  |  |
| | | from | 70 | | |
Abstract
Blood transfusion is a life saving maneuver at which whole blood or blood components are transfused from a donor to a recipient, to replace the loss through bleeding or during surgery, also to treat a severe anaemia, thrombocytopenia, hemophilia or sickle-cell disease. Inspite of its precious role, blood transfusion can be associatd with non- infectious and infectious complications in the form of viral, parasitic or bacterial transfusion transmitted infections .
Bacterial contamination is the most common microbiological cause of transfusion associated morbidity and mortality predominantly caused by the introduction of skin flora (resident or transient) into the units of whole blood or apheresis units during venipuncture.
The most important strategies handled to decrease the transfusion associated morbidity/mortality risk of bacterially contaminated cellular blood products is to improve donor’s skin antisepsis before donation. Skin antiseptic destroys or inhibits growth of micro-organisms on living tissues without causing injurious effects when applied to surfaces of the body as a single antiseptic or a combination of two antiseptics. The most common antiseptics used before blood donation are 70 % alcohol, 2% tincture iodine, 10 % povidone iodine and 2 % chlorhexidine gluconate .
Aim of the study :
The aim of the present study was to evaluate different methods of skin disinfection by comparing the skin flora count reduction percentage after using each .
The study involved 300 randomly selected blood donors at Medical Research Institute Blood Bank, Alexandria University. They were divided into 6 groups, 50 donors each. Each group received a different method of skin disinfection at the venipuncture site ( 70 % alcohol with no let time, 70 % alcohol with 2 minutes let time, 2% tincture iodine with no let time, 2 % tincture iodine with 5 minutes let time, 70 % alcohol followed by 2 % tincture iodine and 10 % povidone iodine followed by 70 % alcohol ). Skin swabs were taken before and after the application of skin disinfectants at the venipuncture site and were cultured to evaluate the bacterial count reduction after application of each method. The isolated bacteria were identified using Gram stain for microscopic examination and different biochemical tests.
Results of the study revealed that :
1- The initial bacterial bioburden present on the venipuncture site prior to disinfection ranged from 2.4× 102 to 9.6 × 104 CFU/cm2 .
2- After application of the 6 different disinfection methods, count reduction percentage was lowest when either 70 % alcohol or 2% tincture iodine were applied with no let time (31.38% and 10% respectively), such bacterial count reduction increased to 84.62% when 70 % alcohol was applied with 2 minutes let time and 90 % when 2 % tincture iodine was applied with 5 minutes let time.
3- Count reduction percentage was highest when either 70 % alcohol followed by 2% tincture iodine or 10 % PVI-I followed by 70 % alcohol were applied (95.92% and 92.43% respectively). Inspite of that result, there was no statistical difference between combined methods and 70% alcohol with 2 minutes let time or 2% tincture iodine with 5 minutes let time.
4- Mean number of bacterial bioburden was higher in males than females, the difference was statistically significant.
5- Weak direct correlation was found between age and initial bacterial bioburden on ACF, the result was not statistically significant.
6- The highest initial bacterial bioburden was among fishermen ( 9.8×104 CFU/cm2) and lowest was for plumbers and health care workers (2.4×102 CFU/cm2) , the difference was statistically significant.
7- Non significant correlation was found between age, sex or occupation and bacterial count reduction percentages after application of skin disinfection methods.
8- Non significant difference was found between the mean count reduction percentages of the high, intermediate and low initial bacterial bioburden groups of blood donors .
9- Coagulase-negative staphylococci were isolated from all blood donors followed by diphtheroids and Bacillus spp. from 66 % and 30% of blood donors respectively, and S. aureus was isolated from only 2% of donors .