Question

To deliver an intravenous solution at 0.20 L/hr to a patient through a needle, a pressure difference between the pressure where the solution enters the needle and the patient’s blood pressure is needed. If the needle has a radius of 1.5 x 10-4 m and is 0.025 m long, assuming a viscosity of 1.0 x 10-3 (N/m2) s for the solution, what must be the difference between solution pressure and the pressure in the vein of the patient? (A) 3.1 x 10-4 N/m2 (B) 0.20 N/m2 (C) 7.0 x 103 N/m2 (D) more than one atmosphere ( i.e. more than 1.01 x 105 N/m2) (E) depends on the ambient pressure.

Answer 1