the different sites at which temperature can be monitored?
Temperature may be monitored via the oral,
rectal, esophageal, nasopharyngeal, and tympanic membrane sites. It can also be
monitored via a pulmonary artery catheter (PAC) or a urinary bladder catheter.
With the exception of the oral route, all other methods provide a generally accurate
and reproducible measurement of the core temperature in the general surgical
patient. However, in the patient undergoing hypothermic cardiopulmonary bypass,
significant gradients can exist between core, blood, and peripheral
temperatures. Blood temperature, as measured by the PAC, reflects the
temperature of the blood coming from the heart-lung machine, with core
temperature (esophageal, nasopharyngeal, tympanic) lagging somewhat behind, and
envelope temperature (rectal) taking even more time to equilibrate during both
cooling and rewarming. Bladder catheter measurements should reflect peripheral
temperature, but with high urine flows they are more likely to closely reflect