During CPR which route provides the most effective vascular access?

• A. Intramuscular
• B. Intraosseous
• C. Subcutaneous
• D. Intravenous

Answer: (B)

In CPR, getting drugs and fluids into the circulation fast is crucial. Peripheral veins are often hard to access because they constrict and collapse during arrest, making IV cannulation slow or unreliable. The intraosseous route delivers meds through the bone marrow’s venous plexus, which quickly feeds into the central circulation. This means drugs reach the heart and brain rapidly, with a level of reliability and speed that IV access often cannot provide in the heat of resuscitation. Because it can be established quickly and remains usable even when blood pressure is extremely low, intraosseous access is the most effective vascular route during CPR. Intramuscular and subcutaneous routes are too slow for rapid boluses or continuous infusions, and IV access, while ideal when readily obtained, may not be achievable promptly in an emergency.