Therapeutic challenges in the management of diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is a severe and frequent life-threatening condition of diabetes. In March 2010, the Joint British Diabetes Societies (JBDS) published national UK guidance on the use of the fixed rate intravenous insulin infusion (FRIII) to manage DKA. This guidance was updated in September 2013. A summary of the guidelines pertinent to intensivists was published in 2014. The national guidance was produced in an effort to prevent the pitfalls associated with recognition, resuscitation, and subsequent management of patients with DKA, and also to reduce the length of hospital stay. Among other things, the guidance recommends the use of bedside blood ketone meters to promote prompt recognition; the use of the FRIII to promote ketone clearance; glucose containing solutions to be administered once blood glucose is below 14mmol/L; administration of potassium after initial resuscitation; and continuation of basal insulin. A national survey conducted in the UK following the publication of the revised JBDS guidance on the management of DKA revealed that the incidence of biochemical abnormalities remains high. The results of the national survey demonstrated that hospital acquired DKA was the third most common cause of DKA and accounted for 7.8% of all DKA episodes. In non-hospital acquired DKA, median time from hospital admission to a diagnosis of DKA was 35min, 0.9% sodium chloride was commenced at a median time of 41min, and the FRIII was commenced at a median time of 60min; 67% of patients were hypokalaemic (serum potassium< 4mmol/L) at 24 h; 28% of patients developed hypoglycaemia (blood glucose< 4mmol/L) at some point during their treatment. Furthermore, these results are in line with a respective study performed at one of largest teaching hospitals in the UK, in which 40% of patients suffered at least one episode of hypoglycaemia and 46% suffered hypokalaemia during the initial 24 h after presentation with DKA. In 2012, the critical care unit of the West Suffolk Hospital (WSH) protocoled the management of DKA. The protocol essentially followed the JBDS guidelines including the administration of 10% glucose solution at blood glucose <14mmol/L, but the protocol also demanded the administration of 20% glucose solution should the blood glucose fall below 6mmol/L. In order to prevent hyperchloraemic metabolic acidosis (HCMA), the critical care protocol recommends the use of Hartmann’s solution with additional potassium chloride, rather than 0.9% saline with pre-mixed potassium chloride. This is possible as the critical care is exempt from NPSA guidance on storing strong potassium. Retrospective case note review of the patients admitted to the critical care unit at the WSH was performed for patients admitted from October 2013 to April 2015. Twenty patients were identified that fulfilled the diagnostic criteria for DKA (capillary ketones> 3mmol/L; blood glucose> 11mmol/L and pH< 7.3). In our cohort none of the patients had hospitalacquired DKA, with 19 being diagnosed promptly in the emergency department. In the emergency department, the median time to initiate fluid therapy was 41min and the time to commence intravenous insulin therapy was 60min, which was similar to the reported results of the national survey. The median time from hospital admission to critical care admission was 3.5 h. The time to resolution of DKA from diagnosis was less than 24 h in 85% of patients; 15% (3/20) patients developed hypoglycaemia during the treatment; 20% (4/20) had pre-existing hypokalaemia before admission to critical care; 24 h after both critical care and hospital admission 65% (13/20) were hypokalaemic. Episodes of hypoglycaemia are independent predictors of increased length of hospital stay, and mortality. The JBDS DKA guidelines recommend the introduction of 10% dextrose solution when the blood glucose is less than 14mmol/L, but stop short of recommending the rate of its administration or introduction of higher concentration of dextrose. The consequences were evident in the national survey