Phlebotomy: Skin Antisepsis
One of the most important first steps in blood collection concerns skin antisepsis, which concerns the destruction of microorganisms on the skin. If the venipuncture site is not disinfected, any bacteria that is on the skin's surface can get into the blood culture and cause inaccurate results. The laboratory will make a note of any microorganisms that were observed in the blood specimen. It is up to the physician to determine if any observed organisms pertain directly to the blood or if they are contaminates from the venipuncture. The physician should carefully consider his findings because misinterpreting any findings could result in inappropriate treatment. If the detected microorganism is mistaken for a pathogen the patient may be given medications that are unnecessary.
There are antiseptic techniques for blood collection that can help to ensure that the venipuncture sites are sterile. Swabsticks and special cleaning pads can be used to clean the skin. Often these cleaning tools contain 10% providone or 1-2% tincture of iodine compounds. Swabsticks that contain providone-iodine should be placed at the site of the needle insertion. This areas should be cleaned first and the swabstick should be moved outward from this site in concentric circles without going over the same area more than once. A 3 to 4 inch area in diameter should be cleaned. Some patients are sensitive to iodine. Because of iodine sensitivities, many health-care facilities use chlorhexide gluconate/isopropyl alcohol for antiseptic purposes. These antiseptic liquids are usually used in blood culture kits that only require a one-step application and are effective with a 30-second scrub.