© American Diabetes Association ®, Inc., 2005 Detection, Prevention, and Treatment of Hypoglycemia in the Hospital
In Brief Hypoglycemia is a worrisome condition for hospitalized patients. Nurses, physicians, and other health care workers must be vigilant in detecting, treating, and most of all preventing hypoglycemia in diabetic patients. Systems and protocols for treating patients with diabetes guide the health care team in achieving glycemic goals for healing and health promotion while providing a safe environment.
There is widespread appreciation of glycemic control for outpatient management of diabetes. However evidence for tight glucose control for inpatient management is also increasing.1 Barriers to tight glucose control stem from concerns about hypoglycemia recognition in patients who are bedridden and those who have altered mental status, who are less likely to be capable of seeking assistance for this condition.2 Diabetes-related cardiovascular events, including stroke and heart disease, are leading reasons for hospitalization. Many of these patients are at risk for hypoglycemia because of their critical health status and altered mental status. Furthermore, medical intervention may place them at risk for sensing signs and symptoms of hypoglycemia.1 The threat of hypoglycemia requires the inpatient team to be vigilant in detecting signs and symptoms, preventing episodes without compromising glycemic control for adequate healing, and treating hypoglycemia episodes appropriately. Hypoglycemia constitutes a medical emergency; however, most individuals recover completely. In the Diabetes Control and Complications Trial (DCCT), there were > 1,000 episodes of loss of consciousness associated with hypoglycemia. However, there were no deaths, myocardial infarctions, or strokes definitively attributed to hypoglycemia, and to date there is no evidence of brain damage resulting from any of these episodes.3 Although no deaths occurred in the individuals participating in the DCCT, hypoglycemia that is not reversed can progress from lethargy to coma and ultimately to death. Even with treatment, there are reported cases of long-lasting severe hypoglycemia leading to transient and even permanent cerebral damage.3
Hypoglycemia occurs from a relative excess of insulin in the blood and results in low blood glucose levels. The level of glucose that produces symptoms of hypoglycemia varies from person to person and varies for the same person under different circumstances.4 Hypoglycemia is common in insulin-treated diabetic patients and may occur in patients taking an insulin secretagogue. It may range from a very mild lowering of glucose (6070 mg/dl), with minimal or no symptoms, to severe hypoglycemia, with very low levels of glucose (< 40 mg/dl) and neurological impairment.5
Signs and symptoms Inpatient team members must be alert to early adrenergic hypoglycemia signs and symptoms, including anxiety, irritability, dizziness, diaphoresis, pallor, tachycardia, headache, shakiness, and hunger.4 When symptoms occur, early treatment involves having the patient eat simple carbohydrate. In an NPO (nothing by mouth) patient, viable alternatives for treating early hypoglycemia include giving an intravenous (IV) bolus of 50% dextrose, or, if absent an IV, giving intramuscular glucagon. However, when sympathetic dysfunction (e.g., diabetic autonomic neuropathy) exists or when adrenergic blockers are being used, these signs and symptoms may be unnoticeable.
Neuroglycopenic signs occur when the brain's dependence on glucose, coupled
with its limited glycogen stores, results in rapid CNS
dysfunction.6 If
warning signs are absent or ignored and the blood glucose level continues to
fall, more severe hypoglycemia may lead to alteration of mental function that
proceeds to headache, malaise, impaired concentration, confusion,
disorientation, irritability, lethargy, slurred speech, and irrational or
uncontrolled behavior, which may be confused with
dementia.4 Notable
CNS dysfunction, including focal seizures, hemiplegia, paroxysmal
choreoathetosis, and patchy brain stem and cerebellar involvement mimicking
basilar artery thrombosis, has also been reported. The medullary phase of
hypoglycemia, characterized by deep coma, pupillary dilatation, shallow
breathing, bradycardia, and hypotonicity, occurs at a blood glucose level of
Individuals with type 1 diabetes are at higher risk for hypoglycemia. The risk is associated with C-peptide negativity (decreased insulin secretion).7 The first line of defense against hypoglycemia is lost when an individual receives exogenous insulin and is unable to regulate insulin levels as plasma glucose declines. Islet secretion is normally a potent stimulus to the glucagon secretory response to hypoglycemia.8 The absent glucagon response may be a direct result of absent insulin secretion and accurately predicts that the second defense against hypoglycemia (increased glucagon secretion) is lost. Therefore, patients with established (i.e., C-peptidenegative) type 1 diabetes are largely dependent on the third defense against hypoglycemia: increased adrenalin or epinephrine secretion.
Patients with type 1 diabetes who have combined deficiencies of glucagon
and epinephrine responses have been shown in prospective studies to suffer
severe hypoglycemia at rates
Risk factors
Hypoglycemia does not occur in people with diabetes who are treated with
medical nutrition therapy (MNT) and exercise alone and is rare in people
treated only with Hospital personnel must consider timing of procedures for individuals with diabetes. It is best to schedule patients first thing in the morning or after a meal to avoid potential hypoglycemia. Sometimes, patients are taken off the nursing unit for procedures during scheduled meal times. Blood glucose monitoring should be performed before the patient leaves the unit, and precautions for treating the patient in the event that hypoglycemia symptoms occur must be considered. Ideally, a hospital staff member or the patient will be able to monitor capillary blood glucose while the patient is off the unit to ensure safety. If the patient is able to eat but is to be taken off the unit just before mealtime, then supplemental carbohydrate can be given to patient. Another potential risk for hypoglycemia is the use of ß-blocker medication in cardiac and hypertensive patients. Using medications for ß-blockade may shift the glycemic threshold for some adrenergic symptoms, but it does not reduce neuroglycopenic symptoms. Several studies evaluating patients taking ß-blockers did show a reduction in symptoms of tremulousness and hunger, but they did not reduce the incidence of symptoms such as diaphoresis or impaired cognition.12 At one time, ß-blockers were contraindicated for insulin-treated patients. Evidence suggests that this hypothetical risk is not clinically significant for cardiac patients with diabetes.12
Balancing glycemic control by preventing hyperglycemia and hypoglycemia is key for providing optimum care of individuals with diabetes. The inpatient team can prevent or reduce hypoglycemic events by 1) recognizing precipitating factors or triggering events; 2) ordering appropriate scheduled insulin or anti-diabetic oral agents; 3) monitoring blood glucose at the bedside; 4) educating patients, family, friends, and staff about symptom recognition and appropriate treatment; 5) providing appropriate nutritional requirements; and 6) applying systems for eliminating or reducing medication and treatment errors in hospitalized patients.
Recognition of precipitating factors
Scheduled insulin therapy Predictably, this approach does not work. If no insulin is given before a meal, the blood glucose level rises substantially and remains elevated at the time of the next meal. Then, a large dose of regular, lispro, or aspart insulin is given, which could cause hypoglycemia, particularly if administered at bedtime without a meal. Standard insulin sliding scales are ineffective, carry the risk of hyperglycemia and hypoglycemia, and generally should be avoided.14 On the other hand, basal and bolus insulin provides a more physiological replacement of insulin. The recent ADA technical review on inpatient diabetes used the term "programmed" or "scheduled insulin requirement" to refer to the dose requirement during hospitalization that is necessary to cover both basal and nutritional needs.1,15 When patients are eating scheduled meals, basal and separate prandial insulin requirements provide good options.
Inpatient use of oral agents A common error in this population of patients is the discontinuation of oral agents in the absence of an alternate method for diabetes control. These patients should instead be converted to a subcutaneous or IV insulin regimen during hospitalization. Management with insulin in these circumstances is safer and has the added benefit of increased dosing flexibility when caloric intake is erratic.2
Glucose monitoring Patients with persistent hypoglycemia may require an overall reduction in insulin dose. Patients who are NPO or require continuous tube feedings should have glucose levels checked at least every 6 hours. In special circumstances, such as an unusual bolus tube-feeding schedule, the timing of the bedside glucose checks should be carefully coordinated with the timing of the feedings.2
Medical nutrition therapy
Applying systems
A team approach is also needed in recognizing and treating patients with hypoglycemia. Reviewing the signs and symptoms of hypoglycemia with nursing staff and patients may prevent severe hypoglycemic episodes. Making bedside glucose monitoring readily available and having an easily interpretable hypoglycemia treatment protocol can ensure efficient and effective care for hypoglycemic patients. When a patient experiences a hypoglycemic episode, assessment at the bedside must include the patient's level of consciousness, respiratory and circulatory status, capillary blood glucose test results, existence of IV access, time and amount of insulin doses, and NPO status or last food and amount of intake. If the patient can safely be treated with oral carbohydrate, use an appropriate choice of liquid or easily dissolved glucose tablets (Table 3). If the patient is unresponsive or NPO, then IV access for quick administration of dextrose or intramuscular injection of glucagon are the preferred treatment methods (Figure 1). Attempting to treat by increasing the IV rate to infuse glucose quickly places patients at risk for fluid overload because 100 cc of 5% dextrose solution offers only 5 g of carbohydrate.
A common error is to overtreat hypoglycemia with an excess of carbohydrate. This, in combination with the counterregulatory hormone response to hypoglycemia, facilitates subsequent hyperglycemia. After treatment of any hypoglycemic episode, frequent bedside glucose monitoring should be continued until a stable glucose level is achieved. Depending on the time of day and insulin peak times, a balanced snack with carbohydrate, protein, and fat (i.e., peanut butter and crackers, or milk) can prolong treatment effectiveness. After treating a hypoglycemic event, search for the cause, correct the problem, and, if indicated, alter insulin or medication dose. This includes giving consideration to age-specific hypoglycemia concerns for pediatric and geriatric patients (Table 4).
Before discharge, patients should receive education in the form of verbal instructions, written materials, and referral for outpatient follow-up to avoid further events.
The threat of hypoglycemia is one barrier to providing optimal glycemic control in the inpatient setting. Prevention is key in ensuring patient safety. Identifying risk factors, implementing protocols, avoiding traditional sliding scale insulin regimens, and changing unsafe prescribing behaviors are ways to avoid severe hypoglycemic events. Reviewing hypoglycemia signs and symptoms with the entire inpatient team, including patients and their significant others, allows for early detection and treatment. Establishing and publishing a simple treatment protocol affords prompt action to appropriately treat various stages of hypoglycemia.
Donna M. Tomky, MSN, RN, C-ANP, CDE, is a nurse practitioner and diabetes educator in the Department of Endocrinology/Diabetes at Lovelace Medical Center in Albquerque, N.M.
2 Lien LF, Bethel AM, Feinglos MN: Inpatient management of type 2 diabetes mellitus. Med Clin North Am 88:1085 1105, 2004[Medline]
3 The DCCT Research Group: The effect of
intensive treatment of diabetes on the development and progression of
long-term complications in insulin dependent diabetes mellitus. New
Engl J Med 329:977
985, 1993 4 Metchich LN, Petit WA, Inzucchi SE: The most common type of hypoglycemia is insulin-induced hypoglycemia in diabetes. Am J Med113 : 317323,2002[Medline] 5 American Diabetes Association: Hospital admission guidelines for diabetes (Position Statement). Diabetes Care 27 (Suppl. 1):S103 , 2004 6 Goetz CG: Textbook of Clinical Neurology. 2nd ed. Philadelphia, Pa., Elsevier 2003, p.822 823 7 The DCCT Research Group: Hypoglycemia in the Diabetes Control and Complications Trial. Diabetes46 : 271286,1997[Abstract]
8 Banarer S,
McGregor VP, Cryer PE: Intraislet hyperinsulinemia prevents the glucagon
response to hypoglycemia despite an intact autonomic response.
Diabetes 51:958
965, 2002 9 White NH, Skor D, Cryer PE, Levandoski LA, Bier DM, Santiago JV: Identification of type 1 diabetic patients at increased risk for hypoglycemia during intensive therapy. N Engl J Med 308:485 491, 1983[Abstract]
10 Cryer PE, Davis
SN, Shamoon H: Hypglycemia in diabetes. Diabetes Care26
: 19021912,2003 11 Cryer PE: Glucose homeostasis and hypoglycemia. In Williams Textbook of Endocrinology. 10th ed., vol. 88. Larsen RP, Kronenberg HM, Melmed S, Polonsky KS, Eds. St. Louis, Mo., WB Saunders,2003 , p. 15891590. 12 Adler E, Paauw D: Medical myths involving diabetes. Prim Care30 : 607618,2003[Medline] 13 Queale WS, Seidler AJ, Brancati FL: Glycemic control and sliding scale insulin use in medical inpatients with diabetes mellitus. Arch Intern Med157 : 545552,1997[Abstract] 14 McDonough KA, DeWitt DE: Inpatient management of diabetes. Prim Care30 : 557567,2003[Medline] 15 Braithwaite SS: Hospital hypoglycemia: not only treatment but also prevention. Endocr Pract 10 (Suppl. 2):89 99, 2004 16 Rafoth RJ: Standardizing sliding scale insulin orders. Am J Med Qual 17:169 170, 2002[Medline] 17 Joint Commission on Accrediation of Healthcare Organizations: Sentinel Event Alert. Issue 23, Sept. 2001. Available online at http://www.jcaho.org
18 Bates DW:
Unexpected hypoglycemia in a critically ill patient. Ann Intern
Med 137:110
116, 2002 19 Piotrowski MM, Hinshaw DB: The safety checklist program: creating a culture of safety in intensive care units. Jt Comm J Qual Improv28 : 306315,2002[Medline]
20 Adlesberg MA,
Fernando S, Spollett GR, Inzucchi SE: Glargine and lispro: two cases of
mistaken identity. Diabetes Care25
: 404405,2002
21 Ragone M, Lando H:
Errors of insulin commission? Clin Diabetes20
: 221222,2002
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