Catheters, Rectal, Tonometry
Definition : Rectal catheters designed for indirect measurement of the partial pressure (i.e., tonometry) of carbon dioxide (PCO2) in the internal mucosa of the sigmoid colon. These catheters typically consist of a 7 Fr gas-impermeable sampling tube, usually with length markers and including a gas-permeable balloon attached at its distal tip. PCO2 in the saline solution inside the balloon is measured with a blood-gas analyzer after equilibrium. Then, the intramucosal pH (pHim) is calculated using the measured PCO2 value and the bicarbonate concentration in a contemporary sample of arterial blood. Tonometry rectal catheters are used in the determination of intramucosal acidosis in the sigmoid colon (e.g., after abdominal aortic surgery)
Entry Terms : "Tonometry Catheters" , "Sigmoid Tonometers" , "Sigmoid Catheters" , "Gastrointestinal Tonometers" , "Manometric Catheters" , "Catheters, Manometric"
UMDC code : 18736