1. Kennedy, Maureen Shawn MA, RN

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Hyperglycemia and poor control of blood glucose levels have been linked in recent studies to poor clinical outcomes, such as stroke, myocardial infarction and other cardiac conditions, postoperative wound infections, and death. In order to shed more light on the problem, ICU nurses and physicians at the Stamford Hospital, a 250-bed community hospital in Stamford, Connecticut, examined the effects of controlling blood glucose levels on patient outcomes. The result was a significant decrease in the hospital mortality rate.


The goal of the protocol was to keep all patients' blood glucose levels below 140 mg/dL without precipitating hypoglycemia. Valerie Neary, director of critical care services, and James Krinsley, director of critical care, led a multidisciplinary team in developing the protocol. Nurses at the bedside were responsible for monitoring the patients' blood glucose levels, determining insulin dosages and routes of administration, and administering the insulin. Adjustments in the frequency of blood glucose measurement were made on the basis of a patient's diet and previous blood glucose levels. In patients who could eat, glucose levels were checked one hour before each meal and at bedtime. In patients receiving enteral feedings or total parenteral nutrition, blood glucose levels were monitored every six hours. Those with blood glucose measurements above 140 mg/dL received insulin according to a guideline; their blood glucose levels were then rechecked after three hours. If a patient's blood glucose measurement was greater than 200 mg/dL at two consecutive measurements three hours apart, the nurse initiated an intravenous insulin infusion.


The study compared outcomes in 800 patients who were admitted between February 23, 2002, and January 31, 2003, before the protocol was established (the baseline group), with outcomes in 800 patients admitted consecutively after February 1, 2003, when the protocol was instituted (the treatment group).


Patients in the two groups were well matched in terms of admission diagnoses, severity of illness, proportions admitted for medical and surgical services, and demographic characteristics. These data were correlated with several outcomes: deaths, length of ICU stay, the need for transfusions of packed red blood cells, and new onset of renal dysfunction or infection.


Some of the significant differences are shown in the table. The most surprising result was the 29% difference in the hospital mortality rates; in the control group, 167 patients (21%) died, compared with 114 patients (15%) in the treatment group, and differences were seen in several of the subgroups of patients. The only patients who did not benefit from the glycemic control protocol were those who were extremely ill upon admission.

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In the treatment group, there was a lower percentage of patients needing packed red blood cells (25% versus 21%, respectively), and ICU stays were shorter. Rates of hypoglycemia, defined as blood glucose levels below 40 mg/dL, were essentially the same in the two groups (0.35% in the control group and 0.34% in the treatment group), as were the rates of new infections.

TABLE. Outcomes with... - Click to enlarge in new windowTABLE.

The study authors point out that because patients were not randomized (historical controls were used), prospective, randomized, controlled trials of intensive glycemic management in acutely ill medical and surgical patients are needed to confirm these findings.-Fran Mennick, BSN, RN


Krinsley JS. Mayo Clin Proc 2004;79(8):992-1000.