Perioperative glucose control: living in uncertain times--Continuing Professional Development

Accuracy of the Nova StatStrip® glucometer in patients undergoing major abdominal surgery: an observational study

PURPOSE

While the Nova StatStrip® Glucose Hospital Meter System (Nova Biomedical, Waltham, MA, USA) is approved for point-of-care testing (POCT) in critically ill patients, its use during major abdominal surgery has not been evaluated. The purpose of this study was to assess the accuracy of the Nova StatStrip glucometer in patients undergoing major hepatobiliary procedures using the Parkes error grid (ISO15197:2013) and criteria defined by the Clinical and Laboratory Standards Institute (CLSI) POCT12-A3 guideline.

METHODS

This study was a post hoc exploratory study of patients participating in a prospective randomized controlled trial on the effects of hyperinsulinemic normoglycemia (HNC) on infectious outcomes after hepatobiliary surgery. Arterial blood samples were collected before surgery and one hour, two hours, and three hours after baseline. Blood glucose levels were analyzed by the Nova StatStrip glucometer and the GEM® PremierTM 5000 blood gas analyzer. Accuracy of the StatStrip glucometer was assessed using the Parkes error grid for type 1 diabetes mellitus (when 99% of samples were within zones A and B on the Parkes error grid and clinical accuracy was acceptable) and the CLSI POCT12-A3 criteria.

RESULTS

Blood glucose levels were analyzed in 135 patients, 70 of whom received the HNC. In the Parkes error grid plotted, all samples at all time-points were within zones A and B. The Nova StatStrip glucometer also satisfied CLSI POCT12-A3 criteria at all time-points.

CONCLUSION

The Nova StatStrip glucometer was accurate in patients undergoing major upper abdominal surgery, independent of the administration of high-dose insulin therapy.

STUDY REGISTRATION

ClinicalTrials.gov (NCT01528189); registered 7 February 2012.

Perioperative insulin therapy

Surgical patients commonly develop hyperglycemia secondary to the neuroendocrine stress response. Insulin treatment of hyperglycemia is required to overcome the perioperative catabolic state and acute insulin resistance. Besides its metabolic actions on glucose metabolism, insulin also displays nonmetabolic physiological effects. Preoperative glycemic assessment, maintenance of normoglycemia, and avoidance of glucose variability are paramount to optimize surgical outcomes. This review discusses the basic physiology and effects of insulin as well as practical issues pertaining to its management during the perioperative period.

Coma and Stroke Following Surgical Treatment of Unruptured Intracranial Aneurysm: An American College of Surgeons National Surgical Quality Improvement Program Study

OBJECTIVE

A large national surgical registry was used to establish national benchmarks and associated predictors of major neurologic complications (i.e., coma and stroke) after surgical clipping of unruptured intracranial aneurysms.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program data set between 2007 and 2013 was used for this retrospective cohort analysis. Demographic, comorbidity, and operative characteristics associated with the development of a major neurologic complication (i.e., coma or stroke) were elucidated using a backward selection stepwise logistic regression analysis. This model was subsequently used to fit a predictive score for major neurologic complications.

RESULTS

Inclusion criteria were met by 662 patients. Of these patients, 57 (8.61%) developed a major neurologic complication (i.e., coma or stroke) within the 30-day postoperative period. On multivariable analysis, operative time (log odds 0.004 per minute; 95% confidence interval [CI], 0.002-0.007), age (log odds 0.05 per year; 95% CI, 0.02-0.08), history of chronic obstructive pulmonary disease (log odds 1.26; 95% CI, 0.43-2.08), and diabetes (log odds 1.15; 95% CI, 0.38-1.91) were associated with an increased odds of major neurologic complications. When patients were categorized according to quartile of a predictive score generated from the multivariable analysis, rates of major neurologic complications were 1.8%, 4.3%, 6.7%, and 21.2%.

CONCLUSIONS

Using a large, national multi-institutional cohort, this study established representative national benchmarks and a predictive scoring system for major neurologic complications following operative management of unruptured intracranial aneurysms. The model may assist with risk stratification and tailoring of decision making in surgical candidates.

Perioperative glucose control in neurosurgical patients

Many neurosurgery patients may have unrecognized diabetes or may develop stress-related hyperglycemia in the perioperative period. Diabetes patients have a higher perioperative risk of complications and have longer hospital stays than individuals without diabetes. Maintenance of euglycemia using intensive insulin therapy (IIT) continues to be investigated as a therapeutic tool to decrease morbidity and mortality associated with derangements in glucose metabolism due to surgery. Suboptimal perioperative glucose control may contribute to increased morbidity, mortality, and aggravate concomitant illnesses. The challenge is to minimize the effects of metabolic derangements on surgical outcomes, reduce blood glucose excursions, and prevent hypoglycemia. Differences in cerebral versus systemic glucose metabolism, time course of cerebral response to injury, and heterogeneity of pathophysiology in the neurosurgical patient populations are important to consider in evaluating the risks and benefits of IIT. While extremes of glucose levels are to be avoided, there are little data to support an optimal blood glucose level or recommend a specific use of IIT for euglycemia maintenance in the perioperative management of neurosurgical patients. Individualized treatment should be based on the local level of blood glucose control, outpatient treatment regimen, presence of complications, nature of the surgical procedure, and type of anesthesia administered.