Plus-Hex CLINICAL
ABSTRACT Diabetic ketoacidosis is a potentially fatal condition if not recognised and acted on swiftly . However , following prompt diagnosis and treatment from the veterinary surgeon and with intensive care from the nursing team , these patients can often make a good recovery . This article discusses the clinical signs , diagnostic aids and care required for the treatment of this patient .
Keywords diabetes mellitus , diabetic ketoacidosis , nursing care , diagnosis
Introduction
Ketoacidosis is the excessive production of ketoacids circulating in the blood , leading to metabolic acidosis and acidaemia . Small amounts of ketoacids can be found in healthy animals but this is not usually enough to cause a disturbance . Ketoacidosis is invariably a serious and life-threatening complication of diabetes mellitus ( DM ), which is often picked up at the time of diagnosis but can also occur in diabetic patients already on treatment .
During diabetic ketoacidosis ( DKA ) the body begins to produce ketone bodies as an alternative energy source from free fatty acids in the liver ( Gear & Mathie , 2011 ). Counter-regulatory hormones such as glucagon , cortisol , growth hormone and catecholamines dominate over a reduced or negligible insulin output , which most commonly occurs when there is a secondary triggering disease , as shown in Table 1 ( Skelly , 2018 ).
The lack of insulin allows free fatty acids to be released into the circulation and taken up by the liver for ketoacid production ( Skelly , 2018 ). While ketone bodies can be adequately used as a source of energy , animals in DKA produce ketones that exceed the rate of utilisation , resulting in ketonaemia , ketonuria and acidosis .
Table 1 . Conditions that may trigger diabetic ketoacidosis ( Boag , 2012 ).
Bacterial infections
Inflammatory disease
Endocrinopathy
Other
Urinary tract infection Pneumonia Pyometra Pyoderma Prostatitis
Pancreatitis
Hyperadrenocortiscism Hypothyroidism ( dog ) Hyperthyroidism ( cat ) Acromegaly
Chronic renal failure Neoplasia Corticosteroid administration
Clinical history
Most cases of DKA will have a history of polyuria , polydipsia , weight loss , muscle wastage and deeper , faster respiration reflecting metabolic acidosis ( Battaglia & Steele , 2016 ; Skelly , 2018 ). On presentation there will be weakness , depression to stupor , tachypnoea , anorexia , vomiting and hepatomegaly ( Gear et al ., 2011 ; Battaglia & Steele , 2016 ; Skelly , 2018 ). In some circumstances , the patient may present with ketotic halitosis , although it is said not everyone can recognise the smell so this should not be considered a definitive symptom ( VetsNow , 2013 ). Should the patient already have been diagnosed with DM , the owner should be questioned about any changes in insulin administration ( Boag , 2012 ).
Diagnostics
Various diagnostics can be performed to aid in the diagnosis of DKA . Skelly ( 2018 ) state the tests seen in Table 2 can be used in most collapsed and volumedepleted patients to aid faster diagnosis . This table shows the recommended diagnostics and a brief overview of expected findings .
In particular , with a patient that is suspected to be in DKA , the VS should ask for a dipstick analysis of the patient ' s urine to assess for ketonuria .
Table 2 . Diagnostic tests used to detect diabetic ketoacidosis . PCV , packed cell volume .
Diagnostic test PCV / total solids
Blood glucose
Dipstick analysis Urine culture analysis
Blood electrolytes
Renal function assessment
Blood gas analysis
Expected findings
Increased due to dehydration
Increased due to unstable DM
Ketones and glucose
Urine culture may show signs of underlying urine infection as a triggering disease
Sodium and chloride may vary from low to normal or high reflecting the balance of free water vs electrolyte loss . Hypokalaemia or hyperkalaemia can be expected , with hypokalaemia being more common
May present as azotaemic
Low pH and negative base excess
Volume 37 ( 4 ) • September 2022
15