Advertisement

Use of the Pao2/Fio2 Ratio in Pulmonary Embolism: Evaluation of its Correlation with Pulmonary Arterial Computed Tomography Obstruction Index

      Rationale and Objectives

      The pulmonary arterial computed tomography obstruction index ratio (PACTOIR) is a parameter that provides an idea of the clinical severity of acute pulmonary embolism (APE). This study aimed to examine the correlation between the PaO₂ /FiO₂ ratio and PACTOIR in patients who presented to the emergency department and received a preliminary diagnosis of APE.

      Materials and Methods

      This study was conducted prospectively in the emergency department. The patients’ sociodemographic characteristics, vital signs, PACTOIR, and PaO₂ /FiO₂ ratio were obtained. The correlation between PACTOIR and PaO₂ /FiO₂ ratio was then statistically evaluated.

      Results

      The study included 50 patients, of whom 31 (62%) were women, and 19(38%) were men. The female patients had a PaO₂ /FiO₂ ratio of 209 ± 67 and PACTOIR of 36.3 ± 15.5. The male patients had a PaO₂ /FiO₂ ratio of 169 ± 43 and PACTOIR of 39.7 ± 19. The PaO₂ /FiO₂ ratio of the patients with APE was negatively correlated with the PACTOIR value at a statistically significant level (r = -0.308, p = 0.031). The regression equation was as follows: PACTOIR = (-0.0869) x (PaO₂ / FiO₂) + (54.489).

      Conclusion

      By calculating the PaO₂ /FiO₂ ratio in patients with APE, the degree of pulmonary artery obstruction and clinical severity can be predicted. Therefore, the ratio PaO₂ /FiO₂ can be used instead of PACTOIR.

      Key Words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Academic Radiology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Ustabaşıoğlu FE
        • Solak S
        • Kula O
        • et al.
        The relationship between computed tomographic obstruction index and pulmonary vein cross-sectional area in acute pulmonary embolism.
        La radiologia medica. 2020; 125: 265-271
        • Guo F
        • Zhu G
        • Shen J
        • et al.
        Health risk stratification based on computed tomography pulmonary artery obstruction index for acute pulmonary embolism.
        Sci Rep. 2018; 8: 1-8
        • Faghihi Langroudi T
        • Shabestari AA
        • Hekmati S
        • et al.
        Association between pulmonary arterial obstruction index and right lateral ventricular wall thickness with in-hospital mortality in patients with acute pulmonary embolism.
        Emerg Radiol. 2021; 28: 327-331
        • Račkauskienė J
        • Gedvilaitė V
        • Matačiūnas M
        • et al.
        Prognostic value of Mastora obstruction score in acute pulmonary embolism.
        Acta Medica Lituanica. 2019; 26: 191
      1. Yuan M, Cui X, Yang C, et al. Evaluation of the therapeutic effect of pulmonary embolism by CT pulmonary angiography combined with clinical indexes. 2021.

      2. Ruigrok D, Noordegraaf AV. Pathophysiology of acute pulmonary embolism. VU Research Portal.25.

        • Prediletto I
        • D'Antoni L
        • Carbonara P
        • et al.
        Standardizing PaO2 for PaCO2 in P/F ratio predicts in-hospital mortality in acute respiratory failure due to COVID-19: A pilot prospective study.
        Eur J Intern Med. 2021; 92: 48-54
        • Pires M
        • Santos J
        • Neto V
        • et al.
        A new ratio with PaO2/FiO2 and pulmonary arterial systolic pressure in the prognosis of intermediate high risk pulmonary embolism.
        Eur Heart J. 2021; 42 (1929): ehab724
        • Knollmann F
        • Chu L
        • Lang JA.
        CT angiography for the detection of pulmonary embolism: role of tube voltage and contrast injection rate on diagnostic confidence.
        Acad Radiol. 2022; 29: S91-SS7
        • Qanadli SD
        • El Hajjam M
        • Vieillard-Baron A
        • et al.
        New CT index to quantify arterial obstruction in pulmonary embolism: comparison with angiographic index and echocardiography.
        AmJ Roentge. 2001; 176: 1415-1420
        • Konstantinides SV
        • Meyer G
        • et al.
        2019 ESC guidelines for the diagnosis and management of acute pulmonary embolism developed in collaboration with the European Respiratory Society (ERS) the task force for the diagnosis and management of acute pulmonary embolism of the European Society of Cardiology (ESC).
        Eur heart j. 2020; 41: 543-603
        • van der Molen AJ
        • Hovius MC.
        Hematuria: a problem-based imaging algorithm illustrating the recent Dutch guidelines on hematuria.
        Am J Roentgen. 2012; 198: 1256-1265
        • Chaosuwannakit N
        • Soontrapa W
        • Makarawate P
        • et al.
        Importance of computed tomography pulmonary angiography for predict 30-day mortality in acute pulmonary embolism patients.
        Eur J Radiol Open. 2021; 8100340
        • Metafratzi ZM
        • Vassiliou MP
        • Maglaras GC
        • et al.
        Acute pulmonary embolism: correlation of CT pulmonary artery obstruction index with blood gas values.
        Am J Roentgen-New Series-. 2006; 186: 213
        • Subramanian M
        • Ramadurai S
        • Arthur P
        • et al.
        Hypoxia as an independent predictor of adverse outcomes in pulmonary embolism.
        Asian Cardiovasc and Thorac Ann. 2018; 26: 38-43
        • Castro D
        • Patil SM
        • Keenaghan M.
        Arterial blood gas.
        StatPearls [Internet]. 2021;
        • Galić K
        • Pravdić D
        • Prskalo Z
        • et al.
        Prognostic value of lactates in relation to gas analysis and acid-base status in patients with pulmonary embolism.
        Croat med j. 2018; 59: 149-155
        • Komissarova M
        • Chong S
        • Frey K
        • et al.
        Imaging of acute pulmonary embolism.
        Emerg radiol. 2013; 20: 89-101
        • Vedovati MC
        • Cimini LA
        • Pierpaoli L
        • et al.
        Prognostic value of respiratory index in haemodynamically stable patients with acute pulmonary embolism: The Respiratory Index model study.
        Eur Heart J: Acute Cardiovasc Care. 2020; 9: 286-292
        • Turetz M
        • Sideris AT
        • Friedman OA
        • et al.
        Epidemiology, pathophysiology, and natural history of pulmonary embolism.
        Seminars in interventional radiology. ThiemeMedical Publishers, 2018
        • Jarman AF
        • Mumma BE
        • Singh KS
        • et al.
        Crucial considerations: sex differences in the epidemiology, diagnosis, treatment, and outcomes of acute pulmonary embolism in non-pregnant adult patients.
        J Am Coll Emerg Physicians Open. 2021; 2: e12378
        • Sheh SH
        • Bellin E
        • Freeman KD
        • et al.
        Pulmonary embolism diagnosis and mortality with pulmonary CT angiography versus ventilation-perfusion scintigraphy: evidence of overdiagnosis with CT?.
        AJR-Am J Roentgen. 2012; 198: 1340