In This Edition
Literature at a Glance
A guide to this month’s studies
- ICU volume and outcomes
- Bicarbonate and contrast-induced nephropathy
- Rate of incidental findings in chest CT angiography
- Consequences of adverse-event reporting by physicians
- Hip fracture comanagement
- Niacin vs. ezetimibe in atherosclerosis
- Effect of hospital pharmacists on readmission rates
- Antibiotics in acute exacerbations of COPD
Higher Patient ICU Inflow Volumes Are Associated with Unplanned Readmissions to ICU
Clinical question: Do higher rates of unplanned ICU readmissions occur on days with high patient inflow volumes?
Background: Patients readmitted to ICUs have longer lengths of stay (LOS) and higher rates of in-hospital mortality. Previous studies suggest many ICU readmissions might be due to premature discharge, but there is little evidence evaluating the impact of patient inflow volumes on the incidence of ICU readmissions.
Study design: Retrospective, cohort study.
Setting: Large, urban, tertiary-care academic medical center in Baltimore.
Synopsis: A retrospective review of 3,233 discharges from a neurosciences critical-care unit revealed 95 unplanned readmissions to the ICU setting within 72 hours of discharge to lower level of care. The odds of one or more discharges becoming an unplanned readmission became significantly higher on days when ≥8 patients were admitted to the ICU (OR, 1.66; 95% CI, 1.03-2.68), and the odds of an unplanned readmission were almost five times higher on days when ≥10 patients were admitted, compared with days when ≤9 patients were admitted (OR, 4.99; 95% CI, 2.45-10.17).
After adjusting for patient complexity, patients discharged on days with ≥10 admissions had higher than twice the odds of becoming an unplanned readmission than patients discharged on days with ≤9 admissions (OR, 2.34; 95% CI, 1.27-4.34).
This study was limited to patients in a neurosciences critical-care unit at a single academic medical center. Further research is needed to better understand how high admission volumes lead to increased unplanned readmission rates.
Bottom line: Days with high patient inflow volumes to the ICU are associated with higher rates of unplanned readmissions to the ICU, and the rate of unplanned readmissions becomes significant once a daily threshold of eight admissions is reached.
Citation: Baker DR, Pronovost PJ, Morlock LL, Geocadin RG, Holzmueller CG. Patient flow variability and unplanned readmissions to an intensive care unit. Crit Care Med. 2009;37(11):2882-2887.
Effectiveness of Sodium Bicarbonate in Contrast-Induced Nephropathy Prevention
Clinical question: Is IV sodium bicarbonate effective for prevention of contrast-induced nephropathy (CIN) in high-risk patients?
Background: CIN is a leading cause of acute kidney injury in the hospital setting. Some studies have suggested IV sodium bicarbonate might reduce risk for CIN; other studies challenge this conclusion.
Study design: Systematic review.
Setting: Published and unpublished randomized, controlled trials performed worldwide.
Synopsis: The research examined in this study was composed of randomized, controlled trials that investigated CIN prevention and included IV sodium bicarbonate in one of the treatment groups. Nine published and 15 unpublished trials were selected for a total of 3,563 patients studied. The overall pooled relative risk of CIN in patients treated with IV sodium bicarbonate compared with normal saline was 0.62 (95% CI, 0.45-0.86), though the strength of this evidence was questioned.
Significant heterogeneity across studies was found (I2=49.1%; P=0.004), partially related to substantially greater treatment effect in published (RR 0.43, 95% CI, 0.25-0.75) versus unpublished (RR 0.78, 95% CI, 0.52-1.17) studies. Publication bias was confirmed statistically. Among the published studies, greater treatment effect favoring bicarbonate over saline tended to be reported in those published before 2008, had fewer patients (<200) and events (<15), had measured events within 48 hours, and were studies of lower quality.
No effects regarding the risk of heart failure, the need for dialysis, or mortality were found, though the studies were not specifically designed to investigate those clinical outcomes. Larger studies are needed to better assess these questions.
Bottom line: IV sodium bicarbonate for CIN prevention in high-risk patients could be less effective than previous reports have suggested.
Citation: Zoungas S, Ninomiya T, Huxley R, et al. Systematic review: sodium bicarbonate treatment regimens for the prevention of contrast-induced nephropathy. Ann Intern Med. 2009;151(9):631-638.
Incidental Findings More Frequent than PE in Chest CT Angiograms
Clinical question: What is the prevalence of incidental findings on chest-computed tomographic angiograms (CTAs) ordered by an ED to evaluate for pulmonary embolism (PE)?
Background: CTAs commonly are ordered by ED physicians to assess for PE. While CTAs might yield findings to support an alternate diagnosis to PE, incidental findings might be found that often require further radiographic or clinical followup. The workup of these incidental findings can be burdensome and low-yield.
Study design: Retrospective chart review.
Setting: Single, academic, tertiary-care hospital in North Carolina.
Synopsis: All patients who underwent CTA evaluation for PE in the ED over two enrollment periods were selected; radiographic findings were compiled and their medical records reviewed. Fifty-five of 589 CTAs (9%) were positive for PE. New incidental findings requiring radiographic or clinical followup were found in 141 cases (24%).
Overall, pulmonary nodules were most common, requiring followup in 73 (13%) cases. Adenopathy requiring followup was seen in 51 cases (9%), and new masses requiring followup were found in 12 cases (2%). Findings to support alternate diagnoses for shortness of breath, hypoxemia, or tachycardia were found in 195 patients (33%), most commonly pleural effusion (19%) and infiltrates (11%). Other incidental findings that required less-urgent clinical attention were common with 615 total findings, most frequently nonmalignant bone findings in 144 cases (24%), mild dependent atelectasis in 137 cases (23%), and emphysema in 69 cases (12%).
Bottom line: Incidental findings requiring followup were more than twice as common as PE (24% vs. 9%) in CTAs ordered to evaluate for PE in an ED.
Citation: Hall WB, Truitt SG, Scheunemann LP, et al. The prevalence of clinically relevant incidental findings on chest computed tomographic angiograms ordered to diagnose pulmonary embolism. Arch Intern Med. 2009;169(21):1961-1965.
Patients Don’t Penalize for Adverse-Outcome Disclosure
Clinical question: What patient or clinical characteristics affect the likelihood of physician reporting of an adverse outcome, and how does adverse-outcome disclosure affect patient perceptions of quality of care?
Background: Harmful adverse events (AE), injuries caused by medical management rather than by the underlying condition of the patient, are common in the U.S. Previous studies have focused on physician and provider attitudes about disclosure. Little is known about how characteristics of the AE affect disclosure, and how disclosure affects patients’ perceptions of quality of care.
Study design: Retrospective cohort study.
Setting: Acute-care hospitals in Massachusetts.
Synopsis: Of 4,143 eligible patients, 2,582 (62%) agreed to a telephone interview that asked about patient experiences with adverse events during their hospital stay. Respondents reporting an AE were asked about disclosure by medical staff, effects of adverse events on their hospital course, and the quality of their hospital care.
Of the 845 AEs reported by 608 patients, only 40% were disclosed, defined as “anyone from the hospital explaining why the negative effects occurred.” The majority of the AEs were related to newly prescribed medications (40%) and surgical procedures (34%). Researchers determined that 31% of the AEs were preventable and 75% were severe. In multivariate analysis, disclosure was less likely if the AE was preventable or if patients had long-term effects from the AE. Patients with an AE were more likely to rate the quality of their hospitalization higher if there had been disclosure.
Bottom line: Disclosure of adverse events by medical personnel is low (40%) in hospitalized patients, even though disclosure of adverse events increases patients’ ratings of quality of care.
Citation: López L, Weismann JS, Schneider EC, Weingart SN, Cohen AP, Epstein AM. Disclosure of hospital adverse events and its association with patients’ ratings of the quality of care. Arch Intern Med. 2009;169(20):1888-1894.
Comanagement of Hip-Fracture Patients by Geriatricians Decreases Time to Surgery, LOS, and Complications
Clinical question: Does comanagement of hip-fracture patients by geriatricians and orthopedic surgeons improve short-term outcomes?
Background: Hip fractures in older adults are associated with considerable morbidity and mortality. A model at a single center, where hip fracture patients are comanaged by geriatricians and orthopedic surgeons, demonstrated decreased LOS, readmission rates, and mortality when compared with national data. This study compares results to a usual-care site.
Study design: Retrospective cohort study.
Setting: Community-based teaching hospital and a tertiary-care hospital in Rochester, N.Y.
Synopsis: Researchers enrolled 314 patients with hip fractures. The 193 patients in the intervention group were comanaged by geriatricians and orthopedic surgeons. The 121 patients in the usual-care group were admitted under the care of orthopedic surgeons, and hospitalists were consulted when deemed necessary. Retrospective chart reviews were performed; complications were defined a priori.
When compared with usual care, patients in the intervention group had significantly shorter times to surgery (24.1 hours vs. 37.4 hours), shorter LOS (4.6 days vs. 8.3 days), fewer complications (30.6% vs. 46.3%), including fewer postoperative infections (2.3% vs. 19.8%), cardiac complications (1.0% vs. 7.4%), cases of thromboembolism (0.5% vs. 5.0%), episodes of bleeding (0% vs. 3.3%), and episodes of hypoxia (6.7% vs. 14.1%). There was no difference in inpatient mortality or 30-day readmission rates.
Further assessment comanagement by hospitalists and comanagement by geriatricians is needed.
Bottom line: Perioperative comanagement of hip-fracture patients by geriatricians and orthopedic surgeons significantly improves short-term outcomes.
Citation: Friedman SM, Mendelson DA, Bingham KW, Kates SL. Impact of a comanaged geriatric fracture center on short-term hip fracture outcomes. Arch Intern Med. 2009;169 (18):1712-1717.
Niacin Is Superior to Ezetimibe in Causing Significant Regression of Carotid Intima-Media Thickness when Combined with a Statin
Clinical question: Is ezetimibe superior to niacin for reducing carotid intima-media thickness (CIMT) in patients with coronary artery disease (CAD) already on statin monotherapy?
Background: Statin montherapy significantly reduces the risk of cardiovascular events, and further lowering of this risk can be achieved by reducing the LDL, using statin intensification, or adding ezetimibe, or by raising the HDL levels by adding niacin therapy. This comparative-effectiveness trial compared the efficacy of these two approaches.
Study design: Prospective, randomized, parallel-group, open-label study.
Setting: Tertiary-care military medical center, and private tertiary-care hospital in Washington, D.C.
Synopsis: Three hundred sixty-three patients with known CAD or CAD equivalent were enrolled, and all of the patients were maintained on statin therapy with LDL <100 and HDL <50. Patients were randomized to ezetimibe 10 mg/day or niacin, starting at 500 mg at bedtime and titrated to 2 g/day. Primary endpoint was a mean change in CIMT after 14 months. Secondary endpoints were change in lipid levels, composite of major cardiovascular events, drug discontinuation, and quality of life.
The trial was terminated early after 208 patients had completed the trial. Although ezetimibe showed greater reduction of LDL, niacin showed significantly greater reduction in the progression of CIMT. Patients receiving niacin experienced fewer cardiovascular events (1% vs. 5%) but had higher rates of withdrawal (15% vs. 9%) due to flushing.
Limitations of the study are small sample size, short follow-up period, and use of CIMT as a surrogate marker for clinical endpoint.
Bottom line: Niacin is superior to ezetimibe in reducing CIMT and raising HDL levels and might be more efficacious in reducing cardiovascular risk.
Citation: Taylor AJ, Villines TC, Stanek EJ, et al. Extended-release niacin or ezetimibe and carotid intima-media thickness. N Engl J Med. 2009;361(22):2113-2122.
Pharmacist-Facilitated Hospital Discharge Program Didn’t Reduce Post-Discharge Healthcare Resource Utilization
Clinical question: Does pharmacist-facilitated hospital discharge reduce hospital readmission rates?
Background: Medication discrepancies at the time of discharge often lead to confusion, medical errors, and readmission to the hospital. Patients who are at high risk of medication errors often are on multiple medications and experience adverse drug events upon discharge.
Study design: Prospective cohort study.
Setting: Tertiary-care, academic teaching hospital in Michigan.
Synopsis: One pharmacist alternated between the resident service and hospitalist service every month. The pharmacist monitored the patients being discharged for appropriateness and accuracy of medications. The pharmacist assessed medication therapy, reconciled medications, screened for adherence concerns, counseled and educated patients, and performed post-discharge telephone follow-up.
Primary outcomes were ED visits within 72 hours and readmission rates by day 14 and day 30.
The study found high numbers of medication discrepancies in the control (33.5%) and intervention (59.6%) groups, and these discrepancies were resolved prior to discharge; however, there was no significant impact on post-discharge ED visits, or 14- and 30-day readmission rates. Post-discharge telephone calls reduced 14-day readmission rates.
Bottom line: Pharmacist-facilitated hospital discharge did not significantly reduce post-discharge ED visits or readmissions.
Citation: Walker PC, Bernstein SJ, Jones JN, et al. Impact of a pharmacist-facilitated hospital discharge program. Arch Intern Med. 2009;169(21):2003-2010.
Questionable Antibiotic Benefit for Patients with Acute COPD Exacerbations
Clinical question: Does the addition of antibiotics to systemic corticosteroids provide additional benefits for patients hospitalized with acute exacerbations of chronic obstructive pulmonary disease (AECOPD)?
Background: The role of antibiotics in the treatment of AECOPD is unclear, particularly in addition to systemic corticosteroids. Many of the studies demonstrating the benefit of antibiotics were conducted several decades before systemic steroids were used routinely for the treatment of AECOPD.
Study design: Randomized, double-blinded, placebo-controlled study.
Setting: Two academic teaching hospitals in the Netherlands.
Synopsis: Two hundred sixty-five acute exacerbations of COPD were enrolled in the study, and patients were randomized to a seven-day course of 200 mg/day of doxycycline or placebo. All patients received systemic corticosteroids, nebulized bronchodilator therapy, and physiotherapy. The study found that doxycycline was equivalent to placebo for the primary endpoint of clinical success on day 30; however, doxycycline was superior to placebo for secondary outcomes of clinical success, clinical cure, symptomatic improvement, microbiological success, and reducing open label antibiotic use on day 10, but not on day 30.
Because the population studied had low levels of advanced antimicrobial resistance, the findings might not be generalizable. Results suggested a difference of treatment effect between subgroups based on C-reactive protein values, but further research is needed.
Bottom line: Patients treated with doxycycline for acute exacerbation of COPD had improved clinical outcomes at day 10, but the benefits were not significant at day 30. Data are still equivocal regarding benefits of antibiotics in patients with acute exacerbations of COPD.
Citation: Daniels JM, Snijders D, de Graaff CS, Vlaspolder F, Jansen HM, Boersma WG. Antibiotics in addition to systemic corticosteroids for acute exacerbations of chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2010;181(2):150-157. TH