Emergencies In Diabetes: Diagnosis, Management And Prevention

Emergencies in Diabetes Contents Preface vii Contributors ix 1 Diabetic Ketoacidosis in Adults Definition Mortality Precipitating factors Pathogenesis Fluid and electrolyte depletion Clinical features Diagnosis Treatment Complications of diabetic ketoacidosis in adults Further reading 1 4 5 6 7 12 14 16 22 30 31 2 Diabetic Ketoacidosis in Childhood Introduction Definition Pathophysiology Differential diagnosis Management Further reading 33 34 35 35 37 39 53 3 Hyperosmolar Non-ketotic Hyperglycaemia Pathogenesis Diagnosis Treatment Further reading 55 56 60 62 71 Preface Diabetes mellitus can usually be reasonably well controlled on a day-to-day basis with modern drug regimens. Nonetheless, the risks of metabolic decompensation and iatrogenic hypoglycaemia remain close at hand. Life threatening hyperglycaemia – with or without ketosis – may be precipitated by intercurrent illness or interruption of antidiabetic therapy; new cases of diabetes frequently present as hyperglycaemic emergencies. Clinical outcomes for patients with diabetes after myocardial infarction or surgery may be compromised by sub-optimal metabolic control, the presence of chronic co-morbidity in the form of microvascular complications or atherosclerosis magnifying these risks. Pregnancy continues to present particular hazards for mother and fetus. Considerable evidence has now accumulated pointing to the prospect of improved outcomes for more patients with diabetes through meticulous attention to clinical care. Inevitably, many patients will experience temporary periods of metabolic instability that can be difficult to manage even in a controlled hospital environment. Experienced clinicians will attest to the challenges often presented by patients with diabetic metabolic emergencies. This book has been written by experienced authors and investigators, each an expert in his or her field. The chapters aspire to present the salient features of each emergency in an accessible format. We hope the book will be of value to a range of health care professionals who care for patients with diabetes. AJK Southampton, UK February 2004 Contributors Aftab M. Ahmad, MD Department of Medicine Royal Liverpool Hospital Prescott Street Liverpool L7 8XP UK Julie A. Edge Paediatric Department The John Radcliffe Headington, Oxford OX3 9DU UK Mark R. Burge, MD University of New Mexico School of Medicine Department of Medicine/ Endocrinology – 5ACC Albuquerque, NM 87131 USA John E. Gerich, MD University of Rochester School of Medicine Department of Medicine Rochester, NY 14642 USA Kathleen M. Colleran, MD University of New Mexico School of Medicine Department of Medicine/ Endocrinology – 5ACC Albuquerque, NM 87131 USA Simon R. Heller, DM FRCP Clinical Sciences Centre Northern General Hospital Sheffield S5 7AU UK David B. Dunger, MD FRCP Department of Paediatrics Box 116, University of Cambridge Addenbrooke’s Hospital Cambridge CB2 2QQ UK Helen B. Holt, MB ChB MRCP (UK) Southampton University Hospitals NHS Trust Southampton SO16 6YD UK 1 Diabetic Ketoacidosis in Adults Andrew J Krentz and Helen B Holt Summary Diabetic ketoacidosis has a reported average mortality of approximately five per cent in Western countries. Mortality is generally higher at the extremes of age. Common precipitating causes include infection, insulin management errors, omission of insulin and new cases of diabetes; in many cases no cause is obvious. Although traditionally considered uncommon in patients with type 2 diabetes, reports in recent years have drawn attention to diabetic ketoacidosis in non-white patients who are often able to discontinue insulin after recovery. Ketoacidosis develops when there is an absolute or, more commonly, a relative insulin defici