Bottom line: Nasal swabs using NAT technology could play a significant role in identifying pathogens in CAP patients. How this technology should affect clinical decision-making and how it might improve outcomes remains unknown.
Citation: Johnstone J, Majumdar S, Fox J, Marrie T. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest. 2008;134(6):1141-1148.
Clinical question: Does the use of intensive insulin therapy decrease mortality in the intensive-care unit (ICU)?
Background: In 2001, Van den Berghe et al (N Engl J Med. 2001;345(19):1359-67) reported a reduction in morbidity and mortality with intensive insulin therapy (IIT) in surgical ICU patients. This study led to the adoption of IIT protocols in many hospitals. Since 2001, further studies have failed to reproduce the same dramatic benefit of IIT.
Study design: Randomized, controlled trial.
Setting: National Guard King Abdulaziz Medical City, a tertiary-care teaching hospital in Saudi Arabia.
Synopsis: Patients were included in this study if they were 18 years or older with serum glucose levels greater than 110 mg/dL during the first 24 hours of ICU admission. There were multiple exclusion criteria, including patients with Type I diabetes, documented hypoglycemia on ICU admission (glucose <40), or diabetic ketoacidosis.
Enrolled patients were randomized to IIT or conventional insulin therapy (CIT). A multidisciplinary team designed the protocols to maintain glucose levels of 80 to 110 mg/dL and 180 to 200 mg/dL in the IIT and the CIT groups, respectively. The primary endpoint measured was ICU mortality.
The study did not produce a statistically significant difference in ICU mortality (13.5% for IIT vs. 17.1% for CIT; P=0.30). The adjusted hypoglycemia rate was 6.8 per 100 treatment days with IIT and 0.4 per 100 treatment days with CIT (P<0.0001). Patients with hypoglycemia had higher ICU mortality (23.8% vs. 13.7%, P=0.02).
In the measurement of secondary endpoints, there was a trend toward lower episodes of severe sepsis and septic shock in the IIT group (20.7% in IIT vs. 27.2% in CIT, P=0.08). However, this result was not statistically significant.
Bottom line: This well-designed study failed to show a survival benefit with IIT use in the critical-care setting. Given the findings of this and several other recent studies, one should question whether IIT should be prescribed as the standard of care in all critically-ill patients.
Citation: Arabi Y, Dabbagh O, Tamim H, et al. Intensive versus conventional insulin therapy: a randomized controlled trial in medical and surgical critically ill patients. Crit Care Med. 2008;36(12):3190-3197.
Clinical question: What are the incidence and risk factors for perioperative cardiac adverse events after noncardiac surgery?
Background: In the past few decades, the incidence of cardiac adverse events (CAEs) for a general surgery population has remained largely unchanged (approximately 1%). This is in spite of multiple studies evaluating predictive models and attempts at preventive treatment, including preoperative coronary revascularization and perioperative beta blockers.
Study design: Prospective observational study.
Setting: Single, large, tertiary-care university hospital.
Synopsis: A total of 7,740 cases were reviewed in this study, which consisted of general surgery (4,937), vascular surgery (1,846), and urological surgery (957). A trained nurse followed up for perioperative CAEs as many as 30 days after the operation via medical chart review, phone calls, and letters. CAEs were defined as: Q-wave myocardial infarction (MI), non-ST elevation MI, cardiac arrest, or new cardiac dysrhythmia. A total of 83 CAEs (1.1% of patients) had cardiac arrest, with cardiac dysrhythmia being most common.
A total of seven preoperative risk factors were identified as independent predictors for CAEs: age 68, BMI 30, emergent surgery, prior coronary intervention or cardiac surgery, active congestive heart failure, cerebrovascular disease, and hypertension. In addition, two intraoperative risk factors were identified: intraoperative transfusion of packed red blood cells and operative duration of 3.8 hours. (The P value was 0.05 for all independent predictors.)