Page 281 - fbkCardioDiabetes_2017

Cardio Diabetes Medicine 2017 257

Effect of acidosis in DKA: abnormal blood viscosity all of which are especially
prevalent in diabetes. DKA complicating acute myo-
The effect of acidosis on heart depends upon the
pH Level. During mild acidosis (pH 7.2-7.35) catechol- cardial infarction increases mortality which may ap-
amine release is increased which is compensated by proach 85%. On the other hand acute myocardial in-
increased inotrophy, chronotrophy , cardiac output farction can be one of the major precipitating factors
and peripheral vascular resistance. for DKA along with infection, omission or inadequate
insulin and intercurrent illness.
Once the Ph level drops below 7.2 , the H+ ions have
a direct cardiac depressant action. This ultimately BULLET POINTS
leads to reduced cardiac output and potentially se-
vere shock. • Diabetic Ketoacidosis consists of the triad of hy-
perglycemia, ketosis and acidosis
DKA and pulmonary oedema : • DKA is associated with absolute or relative insulin
Pulmonary oedema in the absence of left ventricu- deficiency , volume depletion and acid base ab-
lar failure has been reported in DKA. Arterial vaso- normalities
dilation in the periphery as well as central venous • Cardiovascular complications in DKA are second-
constriction can be present during ketoacidosis and ary to electrolyte imbalance and catecholamine
this vasoconstriction could aid in the development of release
pulmonary oedema.
• In DKA most important electrolyte abnormality is
The aetiology may be pulmonary vascular microangi- seen with potassium which can lead to ECG ab-
opathy seen in diabetes. normalities , cardiac arrhythmias and even cardiac
Alveolar ventilator compensation is seen in DKA , arrest
which may precipitate low oxygen saturation and • In acidosis, pHlevel drops below 7.2 will leads to re-
acute respiratory distress syndrome, especially in duced cardiac output and potentially severe shock
those with underlying respiratory disease or acute
respiratory infections. • In DKA insulin deficiency and high levels of ke-
tones and free fatty acids inhibits glucose uptake
Vigorous fluid therapy can precipitate this condition. by the cells and thus deprives the myocardium of
energy utilisation during ischemia
DKA and acute myocardial infarction : • Pulmonary oedema in DKA may be due to pulmo-
Acute myocardial infarction is not only increased in nary vascular microangiopathy
frequency in diabetes but is also associated with
morbidity and mortality. REFERANCE :

Under normal conditions 60-90 % of myocardial en- 1. DuBose TD Jr. Acidosis and alkalosis. In: Kasper D, Fauci A, Stephen Haus-
ergy requirement is met by oxidation of free fatty ac- er S, et al, eds. Harrison’s Principles of Internal Medicine. 19th ed. New
ids. During ischemia, the heart shifts from aerobic to York, NY: McGraw-Hill; 2015. Accessed October 6, 2015.
anaerobic metabolism and thus uses glucose instead 2. Kaufman DC, Kitching AJ, Kellum JA. Acid-base balance. In: Hall JB,
of fatty acid as primary fuel. Schmidt GA, Kress KP, eds. Principles of Critical Care. 4th ed. New York,
NY: McGraw-Hill; 2015.
In DKA insulin deficiency and high levels of ketones 3. Kishore P. Diabetic ketoacidosis. Merck Manual Professional Version. June
and free fatty acids inhibits glucose uptake by cells 1, 2014. .Accessed January 20, 2016.
and thus deprives the myocardium of energy utilisa- 4. Jacoby R, Nesto R. Acute myocardial infarction in the diabetic pa-
tion during ischemia. In DKA there is increased pro- tient: pathophysiology, clinical course and prognosis. J Am CollCardiol.
duction of free radicals which enhance further dam- ;20:736-744.
age to myocardium. An excess of catecholamines 5. Gandhi MJ, Suvarna TT. Cardiovascular complications in diabetic ketoac-
reduce the insulin secretory reserve and causes lip- idosis. Int J DiabDev Countries. 1995;15:132-133. http://diabetes.org.in/
olysis and increased myocardial uptake of free fatty journal/1995_oct-dec/article5.pdf. Accessed October 6, 2015.
acids which are toxic to myocardial cells. 6. Braunwald’s heart disease a textbook of cardiovascular medicine volume
II mann.zipes.libby.bonow
The relationship between diabetes and infarction is
related mainly to the development of atherosclero-
sis and plaque rupture. It is well known that factors
leading to atherosclerosis and plaque rupture include
hyperlipidemias, hypertension, hyperinsulinemia and

Cardio Diabetes Medicine