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Economics, Education, and Policy: Brief Report

A Cost-Effective Screening Method for Preoperative Hyperglycemia

Grek, Sasha MD; Gravenstein, Nikolaus MD; Morey, Timothy E. MD; Rice, Mark J. MD

Author Information
doi: 10.1213/ANE.0b013e3181b7c626

Abstract

Screening for diabetes is controversial1 and expensive, at an estimated cost of between $176 and $332 per new diabetic patient identified.2 Approximately 40 million anesthetics are performed in the United States per year (http://www.asahq.org/patientEducation.htm). This easily accessible population is potentially available for screening. With the current trend toward cost containment, most patients without a preexisting diagnosis of diabetes do not routinely get a preoperative glucose measurement. In the United States, people 20 yr or older have diabetes and prediabetes at a rate of 12.9% and 25.7%, respectively, and many people are unaware of their disease.3 A cost-effective screening methodology in the preoperative environment might advance diagnosis and effect an overall reduction in total health care costs.

In the perioperative setting, suboptimal glucose control has been shown by some authors to be a risk factor for increased postoperative morbidity and mortality.4–8 Patients with undiagnosed diabetes that has been identified preoperatively may benefit from a routine preoperative blood glucose measurement because they could be alerted to their hyperglycemic condition and long-term diabetes management could be implemented earlier in the course of the disease.

Diabetes screening must be financially acceptable to gain widespread appeal.9 The purpose of this study was to assess a potentially inexpensive, easily implemented diabetes and prediabetes screening methodology for identifying undiagnosed pre- and diabetic patients in the perioperative setting. From the personnel cost viewpoint, we hypothesized that the incremental cost of professional nursing time to measure and record the glucose concentration is negligible.

METHODS

After IRB approval and informed consent, 347 adult, nonpregnant fasting patients had a preoperative venous whole blood glucose measurement determined. All patients had verification of overnight fasting status and underwent IV catheter placement in the preoperative holding area. A drop of blood residue remaining on the IV catheter needle was sampled to measure the blood glucose with an Accu-Chek Inform glucometer (Roche Diagnostics, Indianapolis, IN). The cost of each glucometer strip at our institution is $0.37. The blood glucose concentration is automatically converted to a plasma-equivalent value by the meter. The patient’s age and any history of diabetes were recorded. In the event of an increased blood glucose level (≥100 mg/dL), the patient was informed, and the appropriate clinical team was notified that a second fasting glucose should be measured to confirm a diagnosis.

A personal communication from a former executive of one of the major diagnostic companies told us their data showed that, in patients with diabetes, it took 60–90 s to perform glucose testing. We performed a discreet event analysis for adding the process of obtaining the blood glucose value at the time of IV catheter insertion, which added 30–90 s to the process of IV insertion. The only extra steps for the nurse were starting the device, placing a strip into the chamber, and recording the glucose value.

Mean residence time for our patients in the preoperative holding area was determined from the Navicare® software system (Batesville, IN) over the time period of the study.

RESULTS

Three hundred forty-seven fasting patients (age range 19–76 yr; 174 men and 155 women) were tested. Eighteen patients (5.1%) were excluded for either a documented history of diabetes or prediabetes in the medical record or if the patient told the physician obtaining informed consent that they had been previously diagnosed with either diabetes or prediabetes. Of the remaining 329 patients, 9 (2.7%; 6 men and 3 women) had a glucose measurement between 100 and 125 mg/dL. Four patients (1.2%; 2 men and 2 women) had a fasting preoperative glucose measurement more than 125 mg/dL (Table 1). The highest glucose recorded was 224 mg/dL in a 42-yr-old man. Glucose measurements are also categorized by age, because there is a steep increase in the incidence of Type 2 disease after 45 yr of age.10

Table 1
Table 1:
Results from Preoperative Glucose Testing in 329 Patients

The cost for each newly diagnosed patient with prediabetes was $14.22 ($128/9 patients) and for diabetes was $32.00 ($128/4 patients) with an average of $9.85 ($128/13 patients) per newly diagnosed patient.

The mean residence time of patients in our preoperative holding area was 107 ± 6 min, whereas the additional time for the intervention described herein was approximately 0.5–1.5 min (0.4%–1.4% of total residence time).

DISCUSSION

With a cost of only $0.37 per testing strip, the total disposable cost for the study was 347 strips × $0.37, or $128. With respect to equipment, the glucometers are donated to the hospital in exchange for the hospital’s purchase of the strips. Therefore, there is no cost for the device included. This represents the costs for our hospital, and it is sensitive to the particular marginal costs for each particular institution. In addition, all nurses working in our holding area must already be trained in the use of glucometers. The cost of this preoperative test per patient identified ($14.22 for prediabetes and $32.00 for diabetes) is approximately one-tenth of the published estimates of the cost of glucose screening, ranging from $176 (single payer perspective) to $332 (societal perspective) per patient identified with previously unsuspected prediabetes or diabetes.2

This study describes and validates an inexpensive and readily implemented screening test for patients with diabetes or prediabetes, easily used in the preoperative setting. The nursing time involved was minimal and was done in parallel with other preoperative activities. Earlier diagnosis of diabetes is certainly not trivial because diabetic complications are developing during this time period.11

There are 3 major limitations of this study. First, there is an inherent inaccuracy of the Accu-Chek Inform compared with central laboratory glucose measurement devices.12 However, Ghys et al.12 reported the predicted bias of the Accu-Chek Inform for a glucose concentration of 7 mmol/L (126 mg/dL) to be only 0.4 mmol/L (7.2 mg/dL). Slater-Maclean et al.13 studied the Accu-Chek Inform and found a mean bias from reference of −0.25 mmol/L (−4.5 mg/dL) at a mean blood glucose concentration of 121 mg/dL. Second, our patients were each tested only once. The American Diabetes Association recommends confirmation of the glucose measurement on a subsequent day.14 Although we did not formally notify subjects of their diabetic or prediabetic status, a number of methods are available to notify them of their condition and that they should get a second test. Third, there is no guarantee that the information will later be communicated to the patient’s primary care provider.

This fasting preoperative blood glucose screening test is another way that our specialty can help to advance the health and perioperative care of our patients. Given that fewer preoperative laboratory tests are now ordered, this offers a way to initiate earlier identification and subsequent intervention in previously undiagnosed patients with prediabetes and diabetes to improve their immediate and long-term care.

ACKNOWLEDGMENTS

The authors thank Dr. Douglas B. Coursin for reviewing the manuscript and making thoughtful suggestions. They also gratefully acknowledge David A. Paulus, MD, for his assistance in obtaining the holding time data.

REFERENCES

1. U.S. Preventive Services Task Force. Screening for type 2 diabetes mellitus in adults: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2008;148:846–54
2. Zhang P, Englelgau MM, Valdez R, Benjamin SM, Cadwell B, Narayan KM. Costs of screening for pre-diabetes among the U.S. adults: a comparison of different screening strategies. Diabetes Care 2003;26:2536–42
3. Cowie CC, Rust KF, Ford ES, Eberhardt MS, Byrd-Holt DD, Li C, Williams DE, Gregg EW, Bainbridge KE, Saydah SH, Geiss LS. Full accounting of diabetes and pre-diabetes in the U.S. population in 1988–1994 and 2005–2006. Diabetes Care 2009;32:287–94
4. Krinsley J. Perioperative glucose control. Curr Opin Anaesthesiol 2006;19:111–6
5. Gandhi GY, Murad MH, Flynn DN, Erwin PJ, Cavalcante AB, Bay Nielsen H, Capes SE, Thorlund K, Montori VM, Devereaux PJ. Effect of perioperative insulin infusion on surgical morbidity and mortality: systematic review and meta-analysis of randomized trials. Mayo Clin Proc 2008;83:418–30
6. Gandhi GY, Nuttall GA, Abel MD, Mullany CJ, Schaff HV, Williams BA, Schrader LM, Rizza RA, McMahon MM. Intraoperative hyperglycemia and perioperative outcomes in cardiac surgery patients. Mayo Clin Proc 2005;80:862–6
7. Furnary AP, Cheek DB, Holmes SC, Howell WL, Kelly SP. Achieving tight glycemic control in the operating room: lessons learned from 12 years in the trenches of a paradigm shift in anesthetic care. Semin Thorac Cardiovasc Surg 2006;18:339–45
8. Noordzij PG, Boersma E, Schreiner F, Kertai MD, Feringa HH, Dunkelgrun M, Bax JJ, Klein J, Poldermans D. Increased preoperative glucose levels are associated with perioperative morality in patients undergoing noncardiac, nonvascular surgery. Eur J Endocrinol 2007;156:137–42
9. Sheehy AM, Coursin DB, Gabbay RA. Back to Wilson and Jungner: 10 good reasons to screen for type 2 diabetes mellitus. Mayo Clin Proc 2009;84:38–42. Erratum in: Mayo Clin Proc 2009;84:208
10. Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. American Diabetes Association: clinical practice recommendations 2002. Diabetes Care 2002;25(suppl 1):S1–147
11. Harris MI, Eastman RC. Early detection of undiagnosed diabetes mellitus: a US perspective. Diabetes Metab Res Rev 2000; 16:230–6
12. Ghys T, Goedhuys W, Spincemaille K, Gorus F, Gerlo E. Plasma-equivalent glucose at the point-of-care: evaluation of Roche Accu-Chek Inform and Abbott Precision PCx glucose meters. Clin Chim Acta 2007;386:63–8
13. Slater-Maclean L, Cembrowski G, Chin D, Shalapay C, Binette T, Hegadorn K, Newburn-Cook C. Accuracy of glycemic measurements in the critically ill. Diabetes Technol Ther 2008; 10:169–77
14. American Diabetes Association. Standards of medical care in diabetes–2007. Diabetes Care 2007;30:S4–41
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