Radiation exposure from medical imaging in patients with chronic and recurrent conditions.

PURPOSE: Advances in medical imaging have been associated with increased utilization and increased radiation exposure, especially for patients with chronic and recurrent conditions. The authors estimated the cumulative radiation doses from medical imaging for specific cohorts with chronic and recurrent conditions. METHODS: All patients diagnosed with hydrocephalus (n = 1,711), pulmonary thromboembolic disease (n = 3,220), renal colic (n = 5,855), and cardiac disease (n = 11,072) from January 1, 2000, to December 31, 2005, were retrospectively identified. Each imaging examination that used ionizing radiation from 2000 to 2008 was incorporated into an estimate of total effective dose and organ-specific doses. Patients with high levels of radiation exposure after 3 years (total effective dose > 50 mSv; dose to the ocular lens > 150 mSv) were identified. RESULTS: The mean estimated effective doses for the surviving diagnostic cohorts after 3 years were 12.3 mSv for patients with hydrocephalus, 21.7 mSv for those with pulmonary thromboembolic disease, 18.7 mSv for those with renal colic, and 14.0 mSv for those with cardiac disease. Among patients with hydrocephalus, 26.3% (339 of 1,291) had radiation doses > 150 mSv to the ocular lens within 3 years. In all cohorts, the proportion of patients with total effective doses > 50 mSv within 3 years was significantly higher for those diagnosed in 2004 and 2005 than for those diagnosed in 2000 and 2001. CONCLUSION: Patients with hydrocephalus, pulmonary thromboembolic disease, renal colic, and cardiac disease received radiation exposures that may put them at increased risk for cancer. Moreover, the proportion who received estimated total effective doses > 50 mSv within 3 years was significantly higher for those diagnosed most recently. It is the responsibility of institutions and physicians to critically evaluate their infrastructures, diagnostic strategies, and imaging techniques for each individual patient, with an eye toward minimizing cumulative medical radiation exposure.

Glycemic control in critically ill patients before and after institution of an intensive insulin infusion protocol: circadian rhythm and the quality duration calculator.

INTRODUCTION: A circadian rhythm of blood glucose values has been recently reported in critically ill patients, but there are no reports of how this rhythm is altered by a continuous intensive insulin infusion therapy protocol (IIT). We wished to examine the effect of IIT on this rhythm as well as to describe the use of the quality duration calculator (QDC) for the evaluation of glycemic control before and after IIT. METHODS: This was a retrospective multihospital observational study that took place in the medical and surgical intensive care units (ICUs) of 2 tertiary care hospitals. Cohorts of consecutively admitted critically ill patients from 2-year periods before and after institution of an IIT protocol were examined. Laboratory, demographic, and outcome data were extracted from hospital databases. RESULTS: We studied 167,645 blood glucose measurements from 8,327 patients. We observed a circadian rhythm of blood glucose control in the pre-IIT cohort that was greatly attenuated in the post-IIT cohort. The difference between the morning and the average daily blood glucose in the pre-IIT cohort was 3.53 mg/dL (P < .001), and the difference between these values in the post-IIT cohort was 1.10 mg/dL (P = .031). In addition, the circadian nature of hyperglycemia incidence observed in the pre-IIT cohort was not seen in the post-IIT cohort. The amount of time spent in goal glycemic range increased from 23.69% (95% CI 23.01-24.38) in the pre-IIT cohort to 29.67% (95% CI 29.04-30.31) in the post-IIT cohort as estimated by the QDC. The amount of time spent in the hyperglycemic decreased from 20.17% (95% CI 19.33-20.99) in the pre-IIT cohort to 14.80% (95% CI 14.15-15.39) in the post-IIT cohort. CONCLUSIONS: The circadian rhythm of blood glucose control confirmed in our pre-IIT cohort was lost after institution of IIT. The morning blood glucose value appears to be a reasonable surrogate of overall glycemic control in a critically ill population on IIT, although this may vary based on the degree of control achieved. The QDC method is useful for analyzing glycemic control in patients on IIT.

Mortality before and after initiation of a computerized physician order entry system in a critically ill pediatric population.

OBJECTIVE: A worrisome increase in mortality has been reported recently following the initiation of a computerized physician order entry (CPOE) system in a critically ill pediatric transport population. We tested the hypothesis that such a mortality increase did not occur after the initiation of CPOE in a pediatric population that was directly admitted to the neonatal and pediatric intensive care units at Montefiore Medical Center during two 6-month periods before CPOE and one 6-month period immediately after CPOE was initiated. Mortality in the pre- and post-CPOE time periods was compared, and adjustment for potentially confounding covariates was performed. SETTING: The pediatric and neonatal intensive care units at Montefiore Medical Center. PATIENTS: All patients admitted from the emergency room or operating room or as transfers from other institutions directly to the pediatric and neonatal intensive care units at Montefiore Medical Center. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Overall, 29 (3.16%) of the 917 patients in the pre-CPOE period and nine (2.41%) of the 374 patients in the post-CPOE period died during their hospital stay (p = .466). The power to detect the hypothesized mortality increase was 81.7%. The variables that remained significant risk factors for mortality after adjustment were shock (odds ratio, 9.41; 95% confidence interval, 2.90-30.49), prematurity (odds ratio, 3.57; 95% confidence interval, 1.74-7.30), male gender (odds ratio, 3.31; 95% confidence interval, 1.47-7.69), or a hematologic/oncologic diagnosis (odds ratio, 3.14; 95% confidence interval, 1.44-6.86). Post-CPOE initiation status remained unassociated with mortality after adjusting for all covariates (odds ratio, 0.71; 95% confidence interval, 0.32-1.57). CONCLUSION: Mortality did not increase during CPOE initiation.