July 2010, Issue 21. What's New at AMVS. In addition to our regular ER hours, AMVS is providing emergency and critical care services to your patients:

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1 Page 1 of 5 Having Trouble Viewing this ? Click Here You're receiving this because of your relationship with Aspen Meadow Veterinary Specialists. Please confirm your continued interest in receiving from us. You may unsubscribe if you no longer wish to receive our s. July 2010, Issue 21 In This Issue What's New at AMVS AMVS is dedicated to being a part of our community. This is what we have been up to recently: What's New at AMVS Complication of Diabetes Mellitus Part Two AMVS attended Ella's Walk this year and it was a hit! Ella's Walk is Longmont Humane Society's annual fundraising event in which people walk three miles with their furry friends. Dr. Flynn from AMVS was at a booth answering veterinary questions for those who participated in the walk. In July, we were at the Lefthand Dogwash to benefit the Longmont Humane Society. Two of our nurses, Stephanie Barlett and Katie Schafe, attended, and it was a huge success! There was a great turnout, and the weather held until the end. We met new folks from the community and those new to Colorado as well. Several of our past patients were there, and this gave us a wonderful In addition to our regular ER hours, AMVS is providing emergency and critical care services to your patients: Fridays, all day

2 Page 2 of 5 opportunity to see them at their best. We were glad to see Rocky, a past Parvo virus patient, who has become an integral part of his family since his return to health We also saw Buddy the black lab who was treated by our team about two years ago after his human brother fed him a corn cob. He is a cute old man now who really enjoyed all the attention he received during his bath that day. We have a few more events that we are a part of this summer, including another dogwash, Dog Dayz of Summer (dog days at the local pools), the Rebel Ride (motorcycle ride to benefit Longmont Humane Society), followed by the Animal Affair in October. Complication of Diabetes Mellitus, Part Two: Non-Ketotic Hyperglycemic Hyperosmolar Syndrome By Matt Spiro Emergency Veterinarian Practice points for your next case 1. Can occur in patients who are known diabetics and patients who are not previously known to be diabetic. 2. Rehydration must be accomplished prior to insulin administration. 3. Serum Osmolality = 2(Na + K) + glucose/18 + BUN/2.8 Normal Serum Osmolality = Patients also often have concurrent Renal Disease, Heart Disease or other underlying diseases. 5. Prognosis is guarded to poor.

3 Page 3 of 5 In the March 2010 edition of Veterinary Voice, Dr. Laura Higgins began a discussion of complication of Diabetes Mellitus. In that issue, she focused on Hypoglycemic Crises. In this edition of Veterinary Voice, we will continue the discussion focusing on another complication - Non- Ketotic Hyperglycemic Hyperosmolar Syndrome. Non-Ketotic Hyperglycemic Hyperosmolar Syndrome is a severe presentation of Diabetes Mellitus characterized by a Blood Glucose > 600, lack of ketones in the urine, and Serum Osmolality > 350. The syndrome can occur in patients already known to be diabetic or in patients not previously known to be diabetic. Unlike uncomplicated Diabetes Mellitus or Diabetic Ketoacidotic patients, patients presenting with Non-Ketotic Hyperglycemic Hyperosmolar Syndrome do not have significant ketone production. It is thought that patients, while diabetic, have just enough insulin to prevent lipolyis and ketone production. The absence of urine ketones is often confusing at first but should not alter treatment plans. In this disease, profound hyperglycemia develops from a combination insulin deficiency, stress hormone induced gluconeogenesis, and reduced Glomerular Filtration Rate (GFR). There is no maximum level of renal glucose excretion so reduced GFR must accompany such high blood glucose levels. Reduced GFR is usually caused by dehydration and renal disease. Patients feel ill and nauseated and will not drink appropriate amounts of water. They may also lose water by vomiting. Making matters worse, the hyperglycemia will lead to an osmotic diuresis compounding the dehydration and possibly leading to medulary washout. It may be difficult to appreciate the severity of disease based on physical exam and history alone. While some patients may be mentally inappropriate or show other neurologic signs due to fluid shifts in the brain, others may simply appear depressed and dehydrated. The history is often vague and nonspecific. Full blood work, including urinalysis is necessary for diagnosis. As stated above, patients often have underlying renal disease and/or heart disease but conditions such as neoplasia, infection, or other endocrinopathies should be considered. Examination for heart disease is especially important because fluid therapy will be necessary for treatment. Blood work findings will vary but in addition to hyperglycemia, patients will be azotemic and often appear hyperphospatemic. Patients may be acidotic from uremic and lactic acids. Glucose, Electrolytes and Phosphorus must be closely monitored throughout the course of disease. Rapid reduction in glucose will lead to rapid changes in osmolality and fluid shifting. Fluid shifting is most important across the blood-barrier and rapid shifts

4 Page 4 of 5 will lead to neurologic disease. Sodium must be monitored carefully for the same reason. In addition, sodium levels measured in blood, though possibly elevated, will actually be less than whole body sodium because of the osmotic pull of water into the tissues. As the hyperosmolar state improves, measured serum sodium levels will rise. Potassium may be low due to diuretic loses. This may be magnified later in treatment once insulin is administered. Supplementation may be necessary. Phosphorus may be elevated both due to decreased renal excretion and shifting into the extracellular space. Phosphorus must be monitored and possibly supplemented during treatment. Initial treatment consists of crystalloid fluid rehydration. This must be done prior to insulin administration. Rehydration alone will lead to significant reduction in Blood Glucose. However, rehydration should NOT be done using fast fluid boluses. Instead, rehydration should occur over many hours - preferably 24 hours. Fluid rate is calculated based on patient's maintenance needs, extra loses, and estimated dehydration percentage. Unfortunately, this is often easier said than done. Estimating dehydration can be difficult and rarely will you know the degree of the patient's renal disease. This is why careful monitoring is necessary. The goal is to not decrease Glucose by more than 50mg/dL/hr or Sodium by 1 meq/l/hr. Once the patient is properly hydrated, insulin therapy can be instituted. Insulin should be started at a low dose - commonly 50 percent of what a Diabetic Ketoacidotic (DKA) patient would normally be started at. Insulin can cause rapid decreases in both Blood Glucose and Potassium so it is important to start low. Insulin dosing can always be increased later. Many internal medicine and emergency medicine contain a chart for administering insulin via Constant Rate Infusion (CRI). We do not have permission to reproduce the chart here, but it can be found in many texts. Remember to start with ½ the recommended insulin dosages for a DKA patient and monitor glucose and electrolytes carefully. Protocols for IM insulin administration have also been published but it is more difficult to control Blood Glucose this way so it is not ideal. CRIs are really not difficult to set up or administer and are much easier to fine tune to the individual patient. Once the patient is eating, the patient can be transitioned to long acting insulin. Unfortunately, the prognosis for patients with this syndrome is generally considered to be guarded at best and, often times, poor. Not only is the condition itself life threatening but the disease rarely occurs in patients that do not have underlying concurrent diseases. Owners must be prepared for this. References: Koenig, A. (2009). Hyperglycemic Hyperosmolar

5 Page 5 of 5 Syndrome. In D. Silverstein and K Hopper, Small Animal Critical Care Medicine. (p ). Saunders, St. Louis, Missouri Thanks for your continued support! -Aspen Meadow Veterinary Specialists 104 S. Main Street Longmont, CO (p) (f) info@aspenmeadowvet.com Forward This was sent to info@aspenmeadowvet.com by info@aspenmeadowvet.com Update Profile/ Address Instant removal with SafeUnsubscribe Privacy Policy. Aspen Meadow Veterinary Specialists 104 South Main Street Longmont CO 80501