Clinical decision rules for PE equally accurate
Four clinical decision rules for diagnosing pulmonary embolism (PE) perform similarly when combined with D-dimer testing.
Researchers compared the performance of the Wells rule, the simplified Wells rule, the revised Geneva score and the simplified revised Geneva score in about 800 consecutive patients seen at hospitals in the Netherlands for suspected acute PE. A computer program calculated the probability that each patient had PE using all four rules. D-dimer tests were also performed and the combined results of the rules and the D-dimer tests were used to determine whether patients should get a CT scan and treatment for PE.
Overall prevalence of PE among the patients was 23%, according to CT testing and three-month follow-up. The four rules offered concordant results in 70% of patients. PE was ruled out by the combination of concordant results on the tests and a normal D-dimer in 21% of patients. In the other 79% of patients, CT scanning was indicated either because at least one of the rules indicated that PE was likely (373 patients) or because the D-dimer was abnormal (265 patients). PE was not detected in any of the patients who had discordant results from the rules but a normal D-dimer.
The study also found that, when combined with a normal D-dimer, the four rules excluded PE in similar proportions of patients, ranging from 22% to 24%. The rates of failure (venous thromboembolism within three-month follow-up) did not differ among the different rule and D-dimer combinations. Researchers concluded that all of the rules showed equivalent performance, including the recently introduced simplified versions. This finding is significant because the simplified rules enable easier computation of scores during daily clinical care, the study authors noted. Physicians should choose which rule to use based on preference and acquaintance, they advised.
The study's results may be applicable in a wide range of clinical settings, but, the researchers cautioned, the study was not able to definitively validate the rules for use in excluding PE in inpatients. Only 20% of the studied patients were already admitted to the hospital when PE was suspected. The study also differed from typical clinical practice in that management decisions were based on the results of all four rules, instead of just one, combined with D-dimer. The study appeared in the June 7 Annals of Internal Medicine.
Guidelines for preventing delirium offered by U.K. experts
Guidelines for preventing delirium in inpatients have been developed by the British National Clinical Guideline Centre, and a synopsis of them was published in the June 7 Annals of Internal Medicine.
The synopsis describes guidelines developed by a multidisciplinary group under the methodology of the National Institute for Health and Clinical Excellence (NICE) and includes 13 specific recommendations for preventing delirium. The full guidelines, which were published in July 2010, also address diagnosis and management of delirium.
The prevention recommendations call for at-risk patients to be treated by a trained multidisciplinary team familiar with the patient. The team should provide a tailored multi-component intervention to help the patient avoid dehydration, constipation, hypoxia, infection and immobility. Clinicians should also assess patients for pain, perform medication reviews, provide nutrition support when appropriate and not disturb patients' sleep. Sensory impairment should also be addressed by resolving any reversible causes and making visual and hearing aids available to patients who need them.
The guidelines also recommend that clinicians address cognitive impairment or disorientation by providing appropriate lighting and clear signage, including a visible clock and calendar, and communicating with the patient—reorienting him or her when necessary, introducing cognitively stimulating activities, and facilitating visits from family and friends. The components of the intervention may not seem challenging, the synopsis authors noted, but the real challenge is to “do all of these things all the time to all of the patients who are risk,” they said.
An accompanying editorial explained that the synopsis was published in Annals of Internal Medicine as the start of a new effort to publish “thoughtful synopses of guidelines initially released in other venues but whose topics are highly relevant to the practice of internal medicine and its subspecialties.”
Overanticoagulation management guidelines effective in very elderly
The American College of Chest Physicians' (ACCP) recommendations for managing overanticoagulation are effective in patients age 75 years and older, a study found.
In a single-center, observational study in France, researchers examined consecutive hospitalized patients age 75 years and older who were taking warfarin or fluindione with a target international normalized ratio (INR) of 2.0 to 3.0, and who experienced overanticoagulation (defined as INR of 5 or more), from June 2006 through December 2008. Physicians were given a pocket-sized card with ACCP recommendations which state that, in patients with INR of 5 or more and no serious bleeding, Vitamin K antagonists (VKAs) should be withheld, vitamin K1 given in an INR-dependent dose, and INR determined the next day. In patients with serious bleeding, recommendations are to withhold VKAs and give 10 mg vitamin K1 by slow intravenous infusion, supplemented by prothrombin complex concentrates. Researchers assessed INRs on the day of overdosage (day zero), and on the following day (day one). The primary outcome was whether INRs returned to the 1.8 to 3.2 range. The study was published in the June American Journal of Medicine.
On day zero, 239 patients experienced 385 INRs of ≥5. The mean INR was 6.8, with 89% in the 5.0 to 9.0 range, and 11% were 9 or higher. Most had atrial fibrillation and were given warfarin. Fifty-seven percent (n=220) were then managed according to ACCP recommendations, and their mean INR decreased from 6.8 ± 2.4 to 2.7 ± 1.3 between days zero and one (P<0.0001). Fifty-five percent of INRs were within the 1.8 to 3.2 range, 20% were less than 1.8, and 25% were higher than 3.2. Eighty-six percent of INRs were within the 1.5 to 4.5 range. In the subset of patients who had INRs between 5 and 6 on day zero, the mean INR fell from 5.5 ± 0.3 to 2.7 ± 1.3 (P<0.0001) after oral administration of 1 mg vitamin K1 (n=121) and from 5.3 ± 0.3 to 5.0 ± 1.6 (P=0.149) without vitamin K1. Of the covariates included in the multivariate analysis, only the vitamin K1 dose influenced day 1 INRs.
The study is the first to address overanticoagulation management in very old patients; the mean patient age was 86 years, the authors noted. The results are in line with those of nonelderly populations that show low-dose vitamin K1 is more effective in returning INRs to the treatment range than withholding warfarin, they noted. In general, the results suggest that hospitalized elderly patients with INR of 5 to 9, no bleeding and VKA therapy should receive oral vitamin K in a 1 to 2 mg dose, the authors wrote. Those with an INR of 9 or above and no bleeding should receive doses no greater than 5 mg, they noted, “in order to avoid over-correction.”
Model finds 14 COPD symptoms that identify exacerbations
Fourteen symptoms, which can be described in patients' daily diaries, provide a new model for quantifying exacerbations in chronic obstructive pulmonary disease (COPD).
Called the Exacerbations of Chronic Pulmonary Disease Tool (EXACT), the 14-item list includes: breathless today, how breathless today, shortness of breath with personal care, shortness of breath indoors, shortness of breath outdoors, cough today, mucus when coughing, chest congested, chest discomfort, chest tight, difficulty with mucus, weak/tired, sleep disturbed, and scared/worried.
In order to select the items, researchers identified 23 symptoms from patient interviews administered to 410 patients with COPD with an average stable FEV1 of 51% predicted and 1.8 exacerbations in the preceding 12 months. Results appeared in the June issue of Chest.
A total of 222 patients had a physician-diagnosed exacerbation; 188 were stable. Item-level analyses were used in the first stage analyzing 23 criteria. One item was excluded due to poor performance across multiple criteria. A Rasch model was conducted to screen the remaining 22 items for fit to a unidimensional construct. Eight items were removed because of a less-than-good performance. None of the surviving 14 items showed evidence of differential item functioning between stable and exacerbation states (analysis of variance P>0.05 in each case). Internal consistency (person separation index) was excellent at 0.92. Post hoc exploratory factor analysis revealed one dominant factor, with three domains (breathlessness, cough and sputum, and chest symptoms) that accounted for 68% of the variance.
“Previous symptomatic definitions have been limited to the cardinal symptoms of cough, sputum, and breathlessness, but this comprehensive assessment demonstrates that exacerbation symptoms show a much broader spectrum than previously recognized,” the authors wrote
Thrombolysis use doubled in four-year period
Approximately 3.4% to 5.2% of acute ischemic stroke patients received thrombolytics in 2009—about double the 2005 treatment rate, a recent analysis found.
In a secondary analysis of existing data from 2005 and 2009, researchers considered patients as potentially eligible for recombinant tissue-type plasminogen activator (rtPA) if their visits were within diagnosis-related groups 14 (intracranial hemorrhage or stroke with infarct), 15 (nonspecific cerebrovascular accident and precerebral occlusion without infarct), 524 (transient cerebral ischemia) and 559 (acute ischemic stroke with use of a thrombolytic agent). Eligible patients also didn't have a transient ischemic attack (TIA) or hemorrhagic stroke International Classification of Diseases 9th (ICD-9) revision code. Patients who received thrombolysis were identified via ICD-9 code 99.10 and by pharmacy billing records.
Thrombolytic use increased from 1.1% of stroke cases in 2005 to 3.4% in 2009 (P<0.001) within the Medicare Provider and Analysis Review dataset, while it increased from 1.4% to 3.7% within the Premier Hospital database. Pharmacy billing record analysis within Premier for 50-mg or 100-mg doses of rtPA showed 3.4% of cases were treated in 2009. The rate of thrombolysis in 2009 rose to 5.2% by including patients with TIA or hemorrhagic stroke ICD-9 revision codes who received thrombolytics as “ischemic stroke patients receiving rtPA”. Results were published in the July 2011 Stroke.
The upper limit of estimated treatment (5.2%) “represents any thrombolytic use and includes patients who(m) we believe had cases that were miscoded as TIA or hemorrhagic stroke in the numerator,” while the lower limit (3.4%) excludes those patients, and is limited to use of alteplase 50 mg or 100 mg, the authors wrote. The study findings are notably different than those in the researchers' previous report, which found no change in treatment rates between 2001 and 2004, they wrote. rtPA use may have increased between 2005 and 2009 because a new DRG was approved in late 2005 that increased payments to hospitals for acute stroke patients—though the rise in rtPA use began before these bigger payments kicked in, the authors said. Other initiatives, like those to certify primary stroke centers and promote guidelines, may have contributed too, they said.