Needle Angles: Standard medication doses for adults are to be rounded to the nearest tenth (0.1) of a milliliter. The standard 3-mL syringe is calibrated in tenths of a milliliter. The nurse should not administer more than 3 mL per intramuscular or subcutaneous injection site; when a volume greater than 3 mL is required, a 5-mL syringe, calibrated in fifths, may be used.
In cardiac physiology, preload is the end volumetric pressure that stretches the right or left ventricle of the heart.Afterload is the tension or stress developed in the wall of the left ventricle during ejection. In other words, it is the end load against which the heart contracts to eject blood.