Asset Details
Do you wish to reserve the book?
Effect of changes in inspired oxygen fraction on oxygen delivery during cardiac surgery: a substudy of the CARROT trial
Hey, we have placed the reservation for you!
By the way, why not check out events that you can attend while you pick your title.
Oops! Something went wrong.
Looks like we were not able to place the reservation. Kindly try again later.
Are you sure you want to remove the book from the shelf?
Effect of changes in inspired oxygen fraction on oxygen delivery during cardiac surgery: a substudy of the CARROT trial
Do you wish to request the book?
Effect of changes in inspired oxygen fraction on oxygen delivery during cardiac surgery: a substudy of the CARROT trial
Please be aware that the book you have requested cannot be checked out. If you would like to checkout this book, you can reserve another copy
We have requested the book for you!
Your request is successful and it will be processed during the Library working hours. Please check the status of your request in My Requests.
Oops! Something went wrong.
Looks like we were not able to place your request. Kindly try again later.
Journal Article
Effect of changes in inspired oxygen fraction on oxygen delivery during cardiac surgery: a substudy of the CARROT trial
2021
Overview
When hemoglobin (Hb) is fully saturated with oxygen, the additional gain in oxygen delivery (DO
2
) achieved by increasing the fraction of inspired oxygen (FiO
2
) is often considered clinically insignificant. In this study, we evaluated the change in DO
2
, interrogated by mixed venous oxygen saturation (SvO
2
), in response to a change in FiO
2
of 0.5 during cardiac surgery. When patients were hemodynamically stable, FiO
2
was alternated between 0.5 and 1.0 in on-pump cardiac surgery patients (pilot study), and between 0.3 and 0.8 in off-pump coronary artery bypass grafting patients (substudy of the CARROT trial). After the patient had stabilized, a blood gas analysis was performed to measure SvO
2
. The observed change in SvO
2
(ΔSvO
2
) was compared to the expected ΔSvO
2
calculated using Fick’s equation. A total 106 changes in FiO
2
(two changes per patient; total 53 patients; on-pump, n = 36; off-pump, n = 17) were finally analyzed. While Hb saturation remained near 100% (on-pump, 100%; off-pump, mean [SD] = 98.1% [1.5] when FiO
2
was 0.3 and 99.9% [0.2] when FiO
2
was 0.8), SvO
2
changed significantly as FiO
2
was changed (the first and second changes in on-pump, 7.7%p [3.8] and 7.6%p [3.5], respectively; off-pump, 7.9%p [4.9] and 6.2%p [3.9]; all P < 0.001). As a total, regardless of the surgery type, the observed ΔSvO
2
after the FiO
2
change of 0.5 was ≥ 5%p in 82 (77.4%) changes and ≥ 10%p in 31 (29.2%) changes (mean [SD], 7.5%p [3.9]). Hb concentration was not correlated with the observed ΔSvO
2
(the first changes,
r
= − 0.06, P = 0.677; the second changes,
r
= − 0.21, P = 0.138). The mean (SD) residual ΔSvO
2
(observed − expected ΔSvO
2
) was 0%p (4). Residual ΔSvO
2
was more than 5%p in 14 (13.2%) changes and exceeded 10%p in 2 (1.9%) changes. Residual ΔSvO
2
was greater in patients with chronic kidney disease than in those without (median [IQR], 5%p [0 to 7] vs. 0%p [− 3 to 2]; P = 0.049). DO
2
, interrogated by SvO
2
, may increase to a clinically significant degree as FiO
2
is increased during cardiac surgery, and the increase of SvO
2
is not related to Hb concentration. SvO
2
increases more than expected in patients with chronic kidney disease. Increasing FiO
2
can be used to increase DO
2
during cardiac surgery.
Publisher
Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
