Evaluation of a combined transcutaneous carbon dioxide pressure and pulse oximetry sensor in adult sheep and dogs

Abstract

The tcPCO(2) sensor overestimated PaCO(2) in sheep and dogs and followed changes in PaCO(2) with a considerable lag time. The tcPCO(2) sensor might be useful for noninvasive monitoring of changes but cannot be used as a surrogate measure for PaCO(2).

Evaluation of a transcutaneous blood gas monitoring system in critically ill dogs

“…In the present study, PtcCO 2 measurements averaged approximately 20% (9 mm Hg) higher than PaCO 2 measurements. There are very few published studies investigating the use of transcutaneous blood gas monitoring in dogs; however, a study investigating 8 adult dogs anesthetized for orthopedic surgery found a mean ± SD difference between PtcCO 2 and PaCO 2 of 8.9 ± 12 mm Hg 10 minutes after sensor application . Thus, that transcutaneous blood gas monitor also over‐estimated PaCO 2 in that group of dogs and had unacceptably large variability in the measurements.…”

“…Thus, that transcutaneous blood gas monitor also over‐estimated PaCO 2 in that group of dogs and had unacceptably large variability in the measurements. However, the monitor had an acceptable lag time (6.2 min) during the adjustment from normal to hyperventilation . Therefore, the authors cautioned against the use of the monitor to replace PaCO 2 measurements, but recommended that it instead be used to trend PCO 2 values.…”

“…There is limited information in the veterinary literature pertaining to transcutaneous blood gas monitoring in dogs. A study investigating PtcCO 2 measurements in 8 adult healthy dogs undergoing nonemergency orthopedic surgery found that PtcCO 2 over‐estimated PaCO 2 by an average of 10.6 mm Hg and lagged behind changes in PaCO 2 during progression from normal ventilation to hyperventilation (ie, induction of hypocapnia) by approximately 6 minutes . The authors concluded that the PtcCO 2 monitor might be useful for detecting changes or trends in PaCO 2 , but was not accurate enough to be used as a surrogate measurement of PaCO 2 .…”

“…A study investigating PtcCO 2 measurements in 8 adult healthy dogs undergoing nonemergency orthopedic surgery found that PtcCO 2 over‐estimated PaCO 2 by an average of 10.6 mm Hg and lagged behind changes in PaCO 2 during progression from normal ventilation to hyperventilation (ie, induction of hypocapnia) by approximately 6 minutes . The authors concluded that the PtcCO 2 monitor might be useful for detecting changes or trends in PaCO 2 , but was not accurate enough to be used as a surrogate measurement of PaCO 2 . An experimental study using anesthetized dogs demonstrated that PtcO 2 became less accurate compared to PaO 2 as the cardiac output decreased during induced hemorrhage, but the accuracy of PtcO 2 improved after fluid resuscitation .…”

Transcutaneous monitor approximates PaCO2 but not PaO2 in anesthetized rabbits

“…Such a range was deemed clinically inaccurate by some, but not all, authors of the aforementioned studies. One study evaluating the use of PtcCO 2 measurements in inhalant anesthetized sheep and dogs found an even greater magnitude of difference from PaCO 2 (Vogt et al. 2007).…”