Assessing The Application Value PetO₂/PetCO₂ In Pediatric

objectiveAssessing the correlation of PctO2/PaO2 and PctCO2/PaCO2 under different recurrent state to know the significance of PctO2/PctCO2 under microcirculation disorder.MethodsCollecting the sampling of PctO2/PctCO2 and arterial blood gases(ABG)from November 2014 to March 2015 in 56 cases. Meanwhile,noting their clinical data including age、gender、weight、underling diseases、vital signs and outcomes, et al. part of children with repeated sampling according to their states.Results1 There have 36 patients in the normal microcirculation group and getting 75 times of ABG comparison;getting 20 times of ABG comparison from 13 patients in the mildly microcirculation disorder group; getting 15 times of ABG comparison from 7 patients in the seriously microcirculation disorder group;2 In the normal microcirculation group, PctO2/PaO2、PctCO2/PaCO2 both have good correlation (r=0.740vs 0.569); PctO2 have significant difference with PaO2(p< 0.05). In the mildly and seriously microcirculation disorder group, PctCO2/PaCO2 have good correlation (r=0.718vs0.679), PctO2have no relation with PaO2, but PctO2 have significant difference with PaO2(p< 0.05); Under different recurrent state, PctCO2 all have no significant difference with PaO2(p> 0.05).3 In the normal microcirculation group,△PO2is 4.65±3.94(kPa), In the mildly microcirculation disorder group, △PO2 is 7.99±7.99(kPa), In the seriously microcirculation disorder group,△PO2 is 11.71±11.77(kPa)。4 In the normal microcirculation group,the relationship between PaO2 and PctO2 is PaO2=1.17PctO2+3.00(kPa),R2=0.55; the relationship between PaCO2and PctCO2is PaCO2=0.84PctCO2+1.04(kPa),R2=0.29; In the mildly microcirculation disorder group,the relationship between PaCO2 and PctCO2 is PaCO2=1.10PctCO2-0.30(kPa),R2=0.52; In the seriously microcirculation disorder group, the relationship between PaCO2 and PctCO2 is PaCO2=0.87PctCO2+0.52(kPa),R2=0.46.5 In the normal microcirculation group, the AUC of PctO2 and PctCO2 are 0.95 (P=0.00)、0.00 (P=0.122), PctO2 can predict hypoxia with the optimal threshold value given by ROC analysis at 7.85 (kPa)(Sen:87% and Spe:99.4%) of PctO2.PctCO2 can predict CO2 retention with the optimal threshold value given by ROC analysis at 5.45 (kPa)(Sen:69.6% and Spe:57.7%).In the mildly microcirculation disorder group, the AUC of PctO2 and PctCO2 are 0.56 (P=0.151),0.91(P=0.026), PctCO2 can predict CO2 retention with the optimal threshold value given by ROC analysis at 5.05 (kPa)(Sen:100% and Spe:71.6%).In the seriously microcirculation disorder group,the AUC of PctO2 and PctCO2 are 0.59 (P =0.602)、0.86 (P=0.037), PctCO2 can predict CO2 retention with the optimal threshold value given by ROC analysis at 3.95 (kPa)(Sen:100% and Spe:36.4%)Conclusion1 In the normal microcirculation, PctO2 have good correlation with PaO2,the same to PctCO2 and PaCO2, PctO2/PctCO2 both have linear relationship with PaO2/PaCO2 in the linear regresssion,so that,PctO2/PctCO2 can predict PaO2/PaCO2 in some degree. Hence,in order to avoid the crying and fear, PctO2/PctCO2 monitoring can instead of PaO2/PctCO2 in some degree.2 In the mildly and seriously microcirculation disturbance, PctCO2 have good correlation with PaCO2; Hence,PctCO2 can instead of PctCO2 in some degree.But, PctO2 have no relation with PaO2,and PctO2 have significant difference with PaO2, so, PctO2 can not reflect PaO2 well, then, PctO2 can not instead of PaO2.What’s more.As the microcirculation disorder worsening, the greater difference between PctO2 and PaO2.Hence, the difference between PctO2 and PaO2 is obvious, with hints of poor microcirculation perfusion;Therefore,Combined PctO2/PctCO2 monitoring with ABG is needed to critically ill patients who need the ABG.