Metabolic Acidosis
Donald E. Wesson Editor Metabolic Acidosis A Guide to Clinical Assessment and Management
Editor Donald E. Wesson, MD, MBA Baylor Scott and White Health Department of Internal Medicine Texas A&M Health Sciences Center College of Medicine Temple, TX, USA ISBN 978-1-4939-3461-4 DOI 10.1007/978-1-4939-3463-8 ISBN 978-1-4939-3463-8 (ebook) Library of Congress Control Number: 2015954357 Springer Science+Business Media New York 2016 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. Printed on acid-free paper This Springer imprint is published by Springer Nature The registered company is Springer Science+Business Media LLC New York
Preface As delivery of healthcare transitions from a focus on episodes of care delivery to restore health (i.e., sick care) to maintaining health of populations (i.e., population health ), it will become increasingly important to delegate responsibility for care of conditions that threaten health to providers who are more proximal to individuals receiving that care. Many medical conditions for which routine care has been provided by subspecialists and specialists must have this routine care delegated to primary care providers, with possible guidance from subspecialists and specialists, in evolving models of population health. The latter strategy better leverages limited provider resources and allows for better opportunities for providerpatient engagement with the potential for enhanced patient and public outcomes. Metabolic acidosis is a surprisingly common disorder, in both its acute and chronic forms, that threatens overall patient and public health and is a candidate condition for management by primary care providers. Because metabolic acidosis in its chronic and mild forms is typically well compensated by body systems and therefore tolerated reasonably well, it was historically thought to have few if any major untoward effects. By contrast, more recent studies detailed herein show metabolic acidosis to have many consequential untoward effects that can reduce the quality and even the length of life of its sufferers. Widening the army of providers to include primary care providers who can identify and manage this common disorder holds promise to limit its devastating effects. The expert contributors to this book iteratively build toward recommended management of metabolic acidosis by beginning with a basic understanding of the physiology that under most circumstances precludes development of metabolic acidosis and the reasons for the breakdown or overwhelming of these protective mechanisms. They then establish a basic understanding of the pathophysiology of metabolic acidosis to help identify its presence within the sometimes complicated context of the multiple disease processes that can cause it. These experts then develop management strategies based on this physiology and pathophysiology. This recommended management includes not only that carried out by the healthcare provider but that that can be done by the individual patient, including dietary management. v
vi Preface I am indebted to the expert contributors to this book that is designed to be a guide for primary care providers in managing patients with metabolic acidosis and for the education of the wide spectrum of healthcare professional trainees. I am also thankful to the countless patients who volunteered their participation in studies that have enhanced our understanding of their medical conditions, including metabolic acidosis, which has helped in the design of increasingly better management strategies for this common disorder. Their contribution and the work of countless experts, including those contributing this book, have improved the management of metabolic acidosis and limited its devastating consequences. Our hope is that this book will help frontline providers leverage this understanding to further limit the untoward consequences of metabolic acidosis. Temple, TX, USA Donald E. Wesson, MD, MBA
Contents 1 Overview of Acid Base Physiology... 1 Nimrit Goraya and Donald E. Wesson 2 Metabolic Acidosis: Physiology, Presentation, and Diagnosis... 7 Melvin E. Laski 3 Etiologic Causes of Metabolic Acidosis I: The High Anion Gap Acidoses... 17 Thomas D. DuBose Jr. 4 Etiologic Causes of Metabolic Acidosis II: Normal Anion Gap Acidoses... 27 Thomas D. DuBose Jr. 5 The Use of Bedside Urinary Parameters in the Evaluation of Metabolic Acidosis... 39 Daniel Batlle, Khurram Saleem, and Nitin Relia 6 Pathophysiologic Approach to Metabolic Acidosis... 53 Nitin Relia and Daniel Batlle 7 Dietary Contributions to Metabolic Acidosis... 65 Lynda Frassetto 8 The Physiology of the Metabolic Acidosis of Chronic Kidney Disease (CKD)... 77 Nimrit Goraya and Donald E. Wesson 9 Metabolic Acidosis and Cardiovascular Disease... 87 Jeffrey A. Kraut and Glenn T. Nagami 10 Effects of Metabolic Acidosis on Skeletal Muscle... 101 Afolarin Amodu and Matthew K. Abramowitz vii
viii Contents 11 Metabolic Acidosis Effects on Bone and Its Metabolism... 111 Donald E. Wesson 12 Endocrine Consequences of Metabolic Acidosis... 121 Donald E. Wesson 13 Metabolic Acidosis and Progression of Chronic Kidney Disease... 131 Csaba P. Kovesdy 14 Management of Chronic Metabolic Acidosis... 145 Donald E. Wesson Index... 155
Contributors Matthew K. Abramowitz, M.D., M.S. Division of Nephrology, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY, USA Afolarin Amodu, M.D., M.P.H. Division of Nephrology, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA Daniel Batlle, M.D. Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA Thomas D. DuBose Jr., M.D., M.A.C.P., F.A.S.N. Section on General Internal Medicine, Wake Forest School of Medicine, Winston Salem, NC, USA Lynda Frassetto, M.D. Department of Medicine, University of California San Francisco, San Francisco, CA, USA Nimrit Goraya, M.D. Baylor Scott and White Health, Texas A&M Health Sciences Center College of Medicine, Temple, TX, USA Csaba P. Kovesdy, M.D. Division of Nephrology, University of Tennessee Health Science Center, Memphis, TN, USA Jeffrey A. Kraut, M.D. Division of Nephrology, VHAGLA Healthcare System, Los Angeles, CA, USA Melvin E. Laski, M.D. Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA Glenn T. Nagami, M.D. Medicine and Research Services, VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA ix
x Contributors Nitin Relia, M.D. Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA Khurram Saleem, M.D. Department of Nephrology, Northwestern Memorial Hospital, Chicago, IL, USA Donald E. Wesson, M.D., M.B.A. Baylor Scott and White Health, Department of Internal Medicine, Texas A&M Health Sciences Center College of Medicine, Temple, TX, USA