In one aspect, an apparatus for measuring peripheral venous pressure includes a tubing having two ends with one end connectable to a fluid source and the other end connectable to a vein, a fluid controlling device configured to have an on position and an off position, and at least one pressure sensor configured to measure fluid pressures therein. When the fluid controlling device is in the on position, fluid flow in the tubing is allowed to pass through the fluid controlling device, such that the at least one pressure sensor measures both a fluid pressure from the fluid source and a distal venous pressure from the vein. When the fluid controlling device is in the off position, no fluid flow in the tubing is allowed to pass through the fluid controlling device, such that the at least one pressure sensor measures the distal venous pressure from the vein only.