Final answer:
The primary antiseptic for venipuncture is A. 70% isopropyl alcohol, as it effectively denatures proteins and disrupts cell membranes while allowing better penetration than higher alcohol concentrations.
Step-by-step explanation:
The primary antiseptic for venipuncture is A. 70% isopropyl alcohol. This concentration is commonly used because it efficiently denatures proteins and disrupts microbial cell membranes, making it effective at inhibiting microbial growth on the skin. Rubbing alcohol, which refers to either isopropyl alcohol or ethanol based liquids, is often used in healthcare settings for disinfecting the skin prior to injections.
Higher concentrations of alcohol, such as 90%, are not used as the primary antiseptic because they coagulate proteins too quickly, which can inhibit effective penetration into cells. Moreover, lower concentrations, like 60%, may not be as effective at rapidly denaturing proteins. Therefore, 70% isopropyl alcohol is the ideal choice as it offers the best balance between effectiveness and safety for skin disinfection.
It is essential to note that alcohols are volatile and flammable, and they should be used in well-ventilated areas. Additionally, alcohols can cause skin irritation due to their dehydrating effect, but their fast-drying nature and ability to kill bacteria, certain viruses, and fungi make them suitable for quick skin antisepsis.