Problem: Robert is a 60-year old patient with heart failure. As such, his heart doesn't pump blood well, and he has expanded blood volume and elevated venous pressures. Robert asks his doctor why he has so much swelling in his legs (increased interstitial water). His diet has been good; he makes sure he gets adequate protein. Robert's doctor explains that water and sodium have increased Robert's blood volume. Based on this, you think that inside Robert's leg veins, there is: