Research Article

The Use of Saliva Sample Evaluating PaO2, PaCO2, pH, and HCO3 Values in Traumatic Patients under Mechanical Ventilation; As a Non- Invasive Approach than the Arterial Blood Gas Sampling


Background: Arterial Blood Gas (ABG) analysis is a commonly ordered test to investigate respiratory, circulatory, and metabolic status in traumatic patients with inappropriate perfusion and ventilation situations. Difficult sampling, hemorrhage risk of arterial puncture, and other vascular complications lead us to use saliva sampling as a safer non-invasive approach to evaluate PaO2, PaCO2, pH, and HCO3 values.
This study was aimed to evaluate the correlation of PaO2, PaCO2, pH, and HCO3 values between ABG and saliva gas in traumatic patients under mechanical ventilation.
Methods: This was a retrospective cross-sectional study of 18-85-year-old traumatic patients under mechanical ventilation conducted in an academic medical hospital. They were investigated based on age, sex, and ABG values as well their saliva gases values. The Paired t-test, Pearson χ2, and Pearson correlation were used to evaluate the correlation between the gases values in ABG and saliva. Data were analyzed using Mann–Whitney U test and Kolmogorov–Smirnov test.
Results: There were 120 patients including 53 men and 67 women enrolled. None of the factors of arterial and salivary gases were significantly different between men and women. And the amount of these factors is homogeneous in both groups (P <0.05). The mean factors of arterial PaCO2 and HCO3 and saliva PaCO2 and HCO3 were significantly different between smokers and non-smokers.
Conclusion: The values of salivary gases correlated with these of ABG. This can expand the use of salivary gases analysis as an alternative to ABG analysis in clinical settings to reduce the logistic burden of arterial sampling as well as to better perform ventilator device settings. These results were aligned with previous studies.

[1] Theodore AC. UpToDate [Internet]. [cited 2010 Jul 12]; Available from:
[2] Mathers CD, Loncar D. Projections of Global Mortality and Burden of Disease from 2002 to 2030. PLoS Med.2013; 3 (11): e442.
[3] Rowell SE, Barbosa RR, Diggs BS, Schreiber MA; Trauma Outcomes Group, Holcomb JB, et al. Specific abbreviated injury scale values are responsible for the underestimation of mortality in penetrating trauma patients by the injury severity score. J Trauma. 2011;71(2): S384-S8
[4] Russell DW, Janz DR, Emerson WL, May AK, Bernard GR, Zhao Z, et al. Early exposure to hyperoxia and mortality in critically ill patients with severe traumatic injuries. BMC Pulm Med. 2017; 17(1):29.
[5] Salehpour F, Bazzazi AM, Aghazadeh J, Hasanloei AV, Pasban K, Mirzaei F, et al. What do You Expect from Patients with Severe Head Trauma? Asian J Neurosurg. 2018; 13(3):660-3.
[6] Vohra T, Paxton J. Abnormal arterial blood gas and serum lactate levels do not alter disposition in adult blunt trauma patients after early computed tomography. West J Emerg Med. 2013;14(3):212-217.
[7] Mohsenian L, Khoramian MK, Sadat Mazloom S. Prognostic Value of Arterial Blood Gas Indices Regarding the Severity of Traumatic Injury and Fractures of the Femur and Pelvis. Bull Emerg Trauma. 2018;6(4):318-324.
[8] Castro D, Patil SM, Keenaghan M. Arterial Blood Gas. 2021 Sep 20. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022.
[9] Hansen JE, Simmons DH. A systematic error in the determination of blood PCO2. Am Rev Respir Dis. 1977; 115(6):1061-1063
[10] José L. Chicharro. Unidad de Investigacion –Escuela de Medicina Deportiva- Faculated de MedicinaSaliva Composition And Exercise- Universidad Complutense de Madrid, .2009:1-8
[11] Mandel ID. The diagnostic uses of saliva. J Oral Pathol Med. 1990;19(3):119-125.
[12] Mangos JA, McSherry NR. Micropuncture study of sodium and potassium excretion in rat parotid saliva: role of aldosterone. Proc Soc Exp Biol Med. 1969; 132(2):797-801.
[13] Simpson H. Interpretation of arterial blood gases: a clinical guide for nurses. Br J Nurs. 2004 May 13-26;13(9):522-8.
[14] Banoczy J, Albrecht M, Rigo O, Ember G, Ritlop B. Salivary secretion rate, pH, lactobacilli and yeast counts in diabetic women. Acta Diabetol Lat. 1987; 24(3): 223-8.
[15] Girault C, Daudenthun I, Chevron V, TAMION F, LEROY J, Bonmarchand G. Noninvasive ventilation as a systematic extubation and weaning technique in acute-on-chronic respiratory failure: a prospective, randomized controlled study. Am J Respir Crit Care Med. 1999; 160(1):86-92.
[16] Ntoumenopoulos G, Presneill JJ, McElholum M, Cade JF. Chest physiotherapy for the prevention of ventilator-associated pneumonia. Intensive Care Med. 2002; 28(7):850-856.
[17] Zisquit J, Velasquez J, Nedeff N. Allen Test. 2022 Apr 30. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022.
[18] Bijapur MB, Kudligi NA, Asma S. Central Venous Blood Gas Analysis: An Alternative to Arterial Blood Gas Analysis for pH, PCO2, Bicarbonate, Sodium, Potassium and Chloride in the Intensive Care Unit Patients. Indian J Crit Care Med. 2019; 23(6):258-262.
[19] Amann A, Costello Bde L, Miekisch W, Schubert J, Buszewski B, Pleil J, et al. The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva. J Breath Res. 2014; 8(3):034001.
[20] Fueda Y, Matsuda F, Kataoka T. Assessment of noninvasive positive pressure ventilation in healthy young volunteers using salivary stress biomarkers. Future Sci OA. 2020; 6(4):FSO460.
[21] Jensdottir T, Nauntofte B, Buchwald C, Bardow A. Effects of calcium on the erosive potential of acidic candies in saliva. Caries Research. 2007; 41(1):68-73.
[22] Paszynska E, Slopien A, Slebioda Z, Dyszkiewicz-Konwinska M, Weglarz M, Rajewski A. Macroscopic evaluation of the oral mucosa and analysis of salivary pH in patients with anorexia nervosa. Psychiatr Pol. 2014;48(3):453-64.
[23] Effros RM, Casaburi R, Porszasz J, Rehan VK. Assessment of exhaled breath condensate pH [published correction appears in Am J Respir Crit Care Med. 2012 Feb 1;185(3):344. Rehan, Virender K [added]]. Am J Respir Crit Care Med. 2011;183(7):952-953.
[24] Inomata K, Suzuki M, Hoshi M, Kurahashi M. Higashi Nihon Shigaku Zasshi. 1990;9(2):1-10.
[25] Ambrosino N, Clini E. Long-term mechanical ventilation and nutrition. Respir Med. 2004;98(5):413-20.
IssueVol 8 No 4 (2022): Autumn QRcode
SectionResearch Article(s)
Arterial blood gas (ABG) Mechanical ventilation Saliva

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Hajigholam Saryazdi H, Alikiaii B, Rafiei L, Shamsi Kahrizsangi M, Nazemroaya B. The Use of Saliva Sample Evaluating PaO2, PaCO2, pH, and HCO3 Values in Traumatic Patients under Mechanical Ventilation; As a Non- Invasive Approach than the Arterial Blood Gas Sampling. Arch Anesth & Crit Care. 2022;8(4):274-279.