Diagnostic Considerations

Severe metabolic alkalosis is a life-threatening condition; recognizing and treating the condition appropriately is important. The diagnosis of metabolic alkalosis is difficult to miss in patients in the intensive care unit (ICU) because arterial blood gases (ABGs) are measured routinely in most of these patients.

In non-ICU patients, metabolic alkalosis is suspected if electrolytes show an elevated carbon dioxide level. An elevated carbon dioxide level may also be secondary to respiratory acidosis. Because treatments for the 2 conditions differ, differentiating between them by reviewing the clinical condition of the patient and performing ABGs if the elevation in carbon dioxide is severe is important. In addition, check serum K⁺ and ionized Ca²⁺ because metabolic alkalosis is often associated with hypokalemia and decreased serum ionized Ca²⁺ levels.

For a discussion of metabolic alkalosis in children, see Pediatric Metabolic Alkalosis. For a general review of acid-base regulation, see Metabolic Acidosis.

Differential Diagnoses

Respiratory Acidosis

Workup

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Algorithm for metabolic alkalosis.

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Author

Christie P Thomas, MBBS, FRCP, FASN, FAHA Professor, Department of Internal Medicine, Division of Nephrology, Departments of Pediatrics and Obstetrics and Gynecology, Medical Director, Kidney and Kidney/Pancreas Transplant Program, University of Iowa Hospitals and Clinics

Christie P Thomas, MBBS, FRCP, FASN, FAHA is a member of the following medical societies: American College of Physicians, American Heart Association, American Society of Nephrology, Royal College of Physicians

Disclosure: Nothing to disclose.

Coauthor(s)

Sameer Yaseen, MD Staff Nephrologist, Department of Internal Medicine, Division of Nephrology, Mercy Hospital of Des Moines

Sameer Yaseen, MD is a member of the following medical societies: Renal Physicians Association, American Society of Nephrology

Disclosure: Nothing to disclose.

Chief Editor

Vecihi Batuman, MD, FASN Huberwald Professor of Medicine, Section of Nephrology-Hypertension, Interim Chair, Deming Department of Medicine, Tulane University School of Medicine

Vecihi Batuman, MD, FASN is a member of the following medical societies: American College of Physicians, American Society of Hypertension, American Society of Nephrology, International Society of Nephrology, Southern Society for Clinical Investigation

Disclosure: Nothing to disclose.

Acknowledgements

Eleanor Lederer, MD Professor of Medicine, Chief, Nephrology Division, Director, Nephrology Training Program, Director, Metabolic Stone Clinic, Kidney Disease Program, University of Louisville School of Medicine; Consulting Staff, Louisville Veterans Affairs Hospital

Eleanor Lederer, MD is a member of the following medical societies: American Association for the Advancement of Science, American Federation for Medical Research, American Society for Biochemistry and Molecular Biology, American Society for Bone and Mineral Research, American Society of Nephrology, American Society of Transplantation, International Society of Nephrology, Kentucky Medical Association, National Kidney Foundation, and Phi Beta Kappa

Disclosure: Dept of Veterans Affairs Grant/research funds Research

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

Metabolic Alkalosis Differential Diagnoses

Diagnostic Considerations

Differential Diagnoses

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