Abstract A central venous pressure catheter has a long flexible tube containing at least three channels or lumens. At a tip end of the catheter a balloon surrounds the tube and is inflatable via one of the channels. A distal port and a proximal port in the wall of the tube are located on either side of the balloon, respectively, and are connected to the other two channels, respectively. The tip end of the catheter may be inserted via a jugular vein into a patient's superior cava vein near the heart. The balloon is inflated to partially obstruct the flow of blood and to increase the blood pressure at a site of surgery at the head or neck of a patient in the upright position to avoid air embolism as well as to prevent bleeding there. The differential pressure, e.g. in cm H 2 O, between the two ports is made equal to the vertical distance between the distal port and the site of surgery by adjusting the size of the balloon.
A method for preventing air embolism in a patient in an upright position undergoing surgery of the head or neck comprising: (a) inserting a central-venous-pressure multichannel catheter via a subclavian or a jugular vein just into the patient's superior cava vein so that an inflatable balloon portion of said catheter is located in said cava vein near the left artrium of the heart, a distal port and a proximal port of said catheter being spaced apart and on either side, respectively of said balloon; (b) measuring the differential pressure between said proximal and distal ports; and (c) inflating said balloon to partially obstruct the blood flow in said cava vein and raise said measured differential pressure to the blood manometric pressure level corresponding to the vertical distance between said distal port and the site of said surgery so that the blood pressure at the site of surgery relative to the environment is near zero.
Claim 2
Independent Claim
154 words
A method for preventing air embolism in a patient in an upright position undergoing surgery of the head or neck comprising: (a) inserting a central-venous-pressure multichannel catheter via a subclavian or a jugular vein just into the patient's superior cava vein so that an inflatable balloon portion of said catheter is located in said cava vein near the left artrium of the heart, a distal port and a proximal port of said catheter being spaced apart and on either side, respectively of said balloon; (b) measuring the differential pressure between said proximal and distal ports; and (c) inflating said balloon to partially obstruct the blood flow in said cava vein and raise said measured differential pressure to the blood manometric pressure level corresponding to the vertical distance between said distal port and the site of said surgery so that the blood pressure at the site of surgery relative to the environment is near zero.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein said distal and proximal ports are spaced no farther apart than 15 centimeters.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein said distal and proximal ports are spaced no further apart than 3 centimeters.