Uncontrolled diabetes – whether due to circumstance or lack of diagnosis – can lead to a dangerous condition known as diabetic ketoacidosis (DKA). Because of a lack of glucose entering cells (regardless of whether it is due to lack of insulin or insensitivity to insulin), cells increasingly rely on fat stores for fuel. This happens despite the high amounts of circulating glucose (hyperglycemia). As a result, there is an increased production of ketones which are a byproduct of fat metabolism. Ketones are acidic and once accumulated in the blood they alter pH of the entire body causing an acidic environment in all tissues (ketoacidosis). The acidic environment forces electrolytes to be redistributed between the inside and outside of cells (i.e. blood) causing an electrolyte imbalance and disturbances. For example, DKA causes hyperkalemia because potassium (K+) – normally in high levels within the cells – is forced out of the cell and into blood. Exiting K+ is exchanged for incoming H+ (acid) as the body tries to deal with the growing acidosis by storing H+ into cells. The hyperglycemia will also cause polyuria which can quickly lead to dehydration, thus complicating the electrolyte disturbances. DKA is a serious medical condition as there are concurrent stresses on the body: electrolyte disturbances, acidic environment, and hyperglycemia with no glucose entering the cells. If DKA is left untreated, it may progress to a life-threatening “diabetic coma” as the tissues starve and continue to acidify.

DKA can occur in all the different types of diabetes – but it is more common in T1DM due to the lack of insulin.

DKA can be caused by:

• Undiagnosed T1DM where lipid metabolism is needed due to the absence of insulin and ketones accumulate in the blood. DKA may develop and bring the patient for emergency care where the official diagnosis of both DKA and T1DM is made
• Insufficient insulin administration to a person with T1DM. In this case, the tissues can not get glucose into the cells and, as a result, cells turn to lipid metabolism making ketones even in the presence of hyperglycemia.
• Increased insulin demand (i.e. sudden illness or injury, alcohol/drug ingestion) in a person with T1DM leading to lipid metabolism and ketone production.

Clinical manifestations of DKA are similar to diabetes (3P’s of diabetes, fatigue, dehydration) WITH the addition of:

• Fruity smelling breath (presence of ketones)
• Fast, deep breathing (breathing off the acid)
• GI upset (will complicate dehydration)
• Malaise
• Signs of Electrolyte disturbances (i.e. arrhythmia, loss of consciousness, seizures, and hyperkalemia will disrupt every tissue that is electrically excitable)

Section Review

DKA is a serious condition that can result from prolonged lack of glucose intake into the cells, usually as a result of insufficient insulin production/secretion. The lack of glucose uptake into the cells induce a change in metabolism and more fat needs to be metabolized, resulting in the production of acidic ketones. High ketones cause pH changes in the body and as the body tries to compensate for this acidification, K+ is expelled from the cells leading to hyperkalemia and electrolyte disturbances. The resulting hyperglycemia will lead to polyuria causing dehydration which further complicates the electrolyte disturbances. Electrolyte disturbances will manifest as irregular heart rhythms (arrhythmia) and neurological impairments (i.e. loss of consciousness, seizures). The high amount of circulating ketones is noticeable in a fruity breath and the acidosis causing a rapid respiratory rate. This is in conjunction with the signs of DM (i.e. polyuria, polydipsia).

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