The Relationship between Blood Gas and Saliva Gases in Patients Hospitalized in Intensive Care Units

Document Type : Original Article (s)


1 Assistant Professor, Anesthesiology and Critical Care Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Student of Medicine, Student Research Committee, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran


Background: Electrolytes imbalance is one of the most prevalent complications among the patients hospitalized in intensive care unit (ICU) and for early detection of it, concentrations of blood gases are measured. But, phlebotomy is related to secondary complications such as infection in these patients. This study aimed to determine the relationship between the concentrations of blood gases and saliva gases in patients hospitalized in internal care units.Methods: This was a cross-sectional study in internal care units of Alzahra hospital, Isfahan, Iran during 2015-2016. 120 patients admitted in internal care unit were selected and amounts of blood gases including pH, partial pressure of carbon dioxide (PCO2), bicarbonate (HCO3), and partial pressure of oxygen (PO2) were measured in blood and saliva and compared between the two samples.Findings: There were statistically significant direct correlation between the amounts of pH, PCO2, HCO3, and PO2 in blood and saliva (Pearson correlation coefficient of 0.25, 0.74, 0.72, and 0.58, respectively) (P < 0.050 for all).Conclusion: The direct correlation between the concentration of blood and saliva gases suggests that water-electrolyte imbalance probably can be predicted via measuring gases concentration in saliva. This can decrease interventional procedures and finally decrease secondary complications due to repeated phlebotomy in patients hospitalized in intensive care units. More studies are recommended.


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