Inpatients with diabetes on nasogastric feeding often cannot respond to hypoglycemic symptoms and are reliant on carers to blood glucose monitor (BGM) and respond appropriately when problems occur. There is a paucity of literature regarding hypoglycemia in this group. We carried out a retrospective audit to determine the incidence and treatment of hypoglycemia in inpatients with diabetes in a tertiary hospital.
Methods: Subjects were 50 (27male/23female) inpatients with diabetes (age 67.8±13.9y) on nasogastric feeds as per standard hospital protocol. Treatment was insulin (42) or sulphonylureas (8). Patients on insulin infusions or in ICU were excluded. Data was collected from medical notes, BGM records, and medication charts. Hypoglycemia was defined as BGL < 3.5mmol/L. Statistical analysis was by PASW V18.
Results: Feed duration was 13±9.2 days; content: normal carbohydrate (19)/ reduced carbohydrate (31); pattern: bolus (49)/ continuous (1). Hypoglycemia was documented in 23 (46%) patients with 19 (38%) recording >1 episode. Standard BGM monitoring was recorded for 44 (88%) patients. All hypoglycemic patients had increased monitoring with 21 (82.6%) having medication changed in response to this. Medication change was associated with less subsequent hypoglycemia (p=.02). Rate of hypoglycemia per 10 feed days was 1.5±2.8 (insulin-treated) and 2.9±3.5 (SU). There was no statistical association between feed type or treatment and rate of hypoglycemia, but SU treatment was associated with increased incidence of sustained and repeat hypoglycemic episodes (p=.035).
Conclusions: This study highlights the prevalence of hypoglycemia in nasogastric feeding. It strongly supports treatment with insulin rather than sulphonylureas and highlights the need for problem solving action based on blood glucose monitoring.