Author(s)

Kenichi Satoh^1*, Mami Chikuda¹, Ayako Ohashi¹, Miho Kumagai², Akiyoshi Kuji², Shigeharu Joh¹

¹Division of Dental Anesthesiology, Department of Reconstructive Oral and Maxillofacial Surgery, School of Dentistry, Iwate Medical University, Morioka, Japan.
²Division of Special Care Dentistry, Department of Developmental Oral Health Science, School of Dentistry, Iwate Medical University, Morioka, Japan.

Background: Anesthetists should measure the concentration of supplemental oxygen to determine whether patients’ partial pressure of arterial oxygen (PaO₂) is correct during general anesthesia. However, the standard PaO₂ value in obese patients in the supine position is unknown. We evaluated the PaO₂ with respect to the Broca-Katsura obesity index. Materials and Methods: From January 2001 to December 2013, we evaluated 472 patients aged ≥16 years old that underwent general anesthesia in the supine position. The anesthetic charts of 472 patients with an American Society of Anesthesiologists physical status of I or II were retrospectively reviewed to investigate the PaO₂. Results: In patients aged 16 to <65 years old, the PaO₂ was 165.7 ± 25.6 mmHg at a Broca-Katsura index of <20%, 141.8 ± 26.9 mmHg at a Broca-Katsura index of 20% to <40%, 132.7 ± 22.7 mmHg at a Broca-Katsura index of 40% to <60%, and 111.7 ± 34.6 mmHg at a Broca-Katsura index of ≥60%. In patients aged 65 to <84 years old, the PaO₂ was 152.1 ± 23.8 mmHg at a Broca-Katsura index of <20%, 130.6 ± 26.7 mmHg at a Broca-Katsura index of 20% to <40%, and 127.5 ± 11.3 mmHg at a Broca-Katsura index of 40% to <60%. Conclusion: With an increasing Broca-Katsura index, the PaO₂ tended to decrease with age from 16 to <65 years old and 65 to <84 years old. Additionally, the PaO₂ tended to decrease with age from 16 to <65 years at a Broca-Katsura index of 20% to <40%.

Arterial Partial Pressure of Oxygen, Broca-Katsura Index, General Anesthesia, Obesity, Supine Position

Satoh, K. , Chikuda, M. , Ohashi, A. , Kumagai, M. , Kuji, A. and Joh, S. (2015) Evaluation of Partial Pressure of Arterial Oxygen in Obese Patients in Supine Position during General Anesthesia. Open Journal of Anesthesiology, 5, 85-92. doi: 10.4236/ojanes.2015.55017.