Insulin Pump Therapy

Motivated type 1 diabetic patients who are frequently monitoring and self-managing insulin dosages but have not attained their glycemic targets should be considered for an insulin pump protocol. Ideally in these patients, the target should be HbA1c less than 7%, with fluctuations in monitored FSG limited to ±50 mg/dL. A key requisite for pump therapy is the patient's willingness to monitor frequently (up to 6-8 times daily) to ensure a safe transition from the flexible insulin regimen and learn to adjust basal and bolus infusion rates.

Use of the insulin pump in type 2 diabetic patients who fail to achieve therapeutic targets is less clear-cut. Often, insulin resistance accounts for failed outcomes rather than beta-cell insufficiency in these patients. If planning to use the pump, patients need to maintain high daily basal rates of 3 to 5 units per hour, which would mean frequent reloading of the insulin reservoir. On a physiologic basis, pump therapy may or may not overcome insulin resistance. Also, subjective factors such as "winning" expectations and renewed motivation are associated with pump use. The resulting behavior changes along with pumping effects can alter the frustrating course of DM.

Using the insulin pump requires more detailed diabetic education, but starting principles are simple. A basal rate is programmed based on 50% of the da/ s daily insulin requirement. The other 50% is used as reactive therapy to cover meals or make corrections. This can be given as an acute bolus infusion or over 2 to 3 hours. Once patients become proficient in safely covering their ingested carbohydrates and determining their optimal basal rates, they require less professional guidance, and if stable with well-controlled HbA1c levels, they can revisit every 4 to 6 months for periodic organ monitoring and patient reeducation.

The insulin pump is not free of risk. Some patients never master self-monitoring and continue to experience marked swings in blood glucose. Although once thought to result from physiological factors (e.g., unpredictability of diabetic gastroparesis), essentially all patients can develop strategies to overcome such physiologic problems. Most patients have functional problems or some family, school, work, or other environmental issue causing their difficulty adjusting to DM. In these patients and tightly controlled patients, hypoglycemia will remain an ever-present risk until advances in real-time glucose monitoring provide early warning. At a minimum, the family physician should be alerted that issues outside diabetes management need to be addressed.

The other risk is pump failure or catheter dissociation, which halts insulin delivery. If the patient was tightly controlled and the insulin effect was countered by high levels of counter-regulatory hormone, a sudden drop in insulin could provoke a rebound in lipolysis leading rapidly to ketogenesis. If the patient is unaware of the pump failure (e.g., because of infrequent monitoring schedule), a rapid deterioration to diabetic ketoacidosis may occur in less than 24 hours. Another complication is localized infection at the injection site of the 3-day indwelling needle. These complications require local therapy but may become severe enough to require incision, drainage, and antibiotics. Family physicians should be able to treat such problems, but consultation is always an option.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

Get My Free Ebook


Post a comment