Journal watch: Recent studies of note

Recent studies about improving CPR, post-stroke depression treatment, and other topics.

New defibrillators and debriefings improved CPR

Regular debriefings can improve residents' performance during in-hospital cardiopulmonary resuscitations, according to a study.

During the year-long study, internal medicine residents at one university hospital attended weekly debriefing sessions on the prior week's resuscitations. The sessions reviewed performance transcripts from a CPR-sensing and feedback-enabled defibrillator that was used for all cardiac arrests. Quality and outcome data for 123 patients who had a cardiac arrest during the study were compared with data from 101 control resuscitations. The resuscitations in the control period also used a feedback-delivering defibrillator, but no debriefings were conducted.

The study found that the quality of CPR was improved under the debriefing system, as measured by a decrease in the mean ventilation rate and an increase in compression depth. The intervention group of patients also had a higher rate of return of spontaneous circulation (59.4% vs. 44.6%) but no difference in survival to discharge. The study was published in the May 26 Archives of Internal Medicine.

The study authors concluded that the debriefing system (which they called resuscitation with actual performance integrated debriefing [RAPID]) increases the benefits of the audiovisual feedback which is now available from many defibrillators. RAPID may work by sensitizing rescuers to the prompts that the defibrillators offer during resuscitations, or by making residents aware that their performance will be reviewed in an open forum.

Although the study found no difference in survival, the authors concluded that RAPID has the potential to improve both resuscitation training and patient outcomes. They noted that many other post-resuscitation quality factors, such as therapeutic hypothermia and tight glycemic control, could have affected the rates of survival to discharge.

Treat post-stroke depression before it happens, study suggests

A recent study found that preemptively treating patients with an antidepressant following stroke may prevent post-stroke depression.

In the year-long randomized, controlled trial, 176 stroke patients at three U.S. centers were randomly assigned to receive escitalopram, placebo or problem-solving group therapy. Patients taking escitalopram were significantly less likely than those taking placebo or those in the therapy group to develop depression (23.1% vs. 34.5% and 30.5%, respectively).

The authors calculated that 7.2 patients would need to be treated with escitalopram or 9.1 patients with problem-solving therapy to prevent one case of depression. The study appeared in the May 28 Journal of the American Medical Association.

While acknowledging the study's limitations, including a relatively small sample size, the authors said the results suggest that it may be possible to prevent post-stroke depression in a significant number of patients. They noted that previous studies have shown an association between post-stroke depression and increased mortality.

Noting that depression is often missed by physicians during standard stroke care, the authors recommended further study on whether preventive intervention is more effective than early detection and treatment.

Survey raises questions about nurses' role in discussing DNR orders with patients

Nurses are more comfortable discussing do-not-resuscitate (DNR) orders with patients than are doctors, according to a survey.

Researchers surveyed 217 attending internists, 132 medical house officers and 219 staff nurses from two teaching hospitals to directly compare their feelings about DNR orders, specifically the role nurses should play in the DNR process. The survey results appeared in the June Critical Care Medicine.

Overall, approximately 82% of nurses, 69% of attendings and 69% of house officers disagreed somewhat or disagreed strongly with the statement that nurses should never initiate DNR discussions. Of the three groups, nurses were least likely to report that discussing DNR orders with patients or families was difficult but were most likely to believe that they should not recommend a DNR order. Nurses were less confident than attendings but as confident as house officers in their ability to discuss consent for DNRs with patients.

Although the survey was small and involved only two hospitals in the same city, the authors concluded that the results may have value for future discussions of nurses' roles in the DNR process. In particular, they questioned why nurses are often not allowed to initiate DNR discussions and suggested a reevaluation of nurses' and physicians' roles in this area of end-of-life care.

In-hospital interventions for secondary prevention of ACS

In-hospital interventions may help reduce mortality in patients with acute coronary syndromes (ACS), according to a preliminary study.

Outpatient programs for secondary prevention of ACS have been shown to be effective, but little research has been done on inpatient interventions. Swiss and Canadian researchers performed a systematic review of 26 studies to determine the effectiveness of secondary prevention interventions in the inpatient setting. Before-after studies and controlled clinical trials that involved at least a patient-level intervention in a population with ACS and examined rates of mortality, readmission or reinfarction as outcomes were included. Interventions were classified as patient-level interventions with or without provider-level or system-level interventions. The results were published online June 9 by Circulation.

Among 14 studies that provided follow-up data on all-cause mortality at one year, the relative risk was 0.79 (95% CI, 0.69 to 0.92). However, the mortality benefit was greater in before-after studies than in controlled clinical trials (relative risk, 0.77 vs. 0.96). Greater mortality benefit was also seen with interventions that had a provider- or system-level rather than only a patient-level component (relative risk, 0.77 vs. 0.93).

The authors wrote that the evidence supporting inpatient interventions for ACS is “promising but not definitive” because a statistically significant mortality benefit was seen only in before-after trials involving multilevel rather than solely patient-level interventions. In addition, their study was limited by the design of the included trials and the heterogeneity of the interventions, among other factors. The authors called for future randomized trials to assess which intervention components have the greatest effect on outcomes.

No gender differences in PCI outcomes, study finds

The gender gap in outcomes after percutaneous coronary intervention (PCI) has disappeared, with women faring as well as men in both the short- and long-term, a study has found.

Earlier studies have shown that PCI was riskier in women than men, in part because women have smaller arteries. PCI has improved over the last decade, however, with new techniques, stents and medications.

To test the effects of the recent advances, researchers analyzed data from 18,885 patients who underwent PCI at the Mayo Clinic in Rochester, Minn. between 1979 and 2004. Patients were divided into two groups: those treated between 1979 and 1995 (“early group”) and those treated between 1996 and 2004 (“recent group”). Women were older than men at the time of PCI by an average of about five years, and were more likely to have severe or unstable chest pain, diabetes and high blood cholesterol levels. The study was published in the June 10 online issue of the Journal of American College of Cardiology.

The immediate success rate for PCI was 89% in women and 90% in men. Among women, 30-day mortality fell from 4.4% in the early group to 2.9% in the recent group (P= 0.002). Among men, 30-day mortality fell from 2.8% to 2.2% in the same time period (P= 0.04). When researchers adjusted for the greater age and health problems of women at the time of PCI, there were no significant mortality differences between men and women either at 30 days or one year after PCI.

The study should reassure many physicians who, research has shown, are more reluctant to refer women for invasive procedures like PCI, said lead author Mandeep Singh, ACP Member, in a release. “Raising awareness among physicians will help us overcome this referral bias. The decision to refer a patient for PCI should not be influenced by gender,” Dr. Singh said.

QRS duration predicts outcomes in heart failure hospitalizations

Patients with prolonged QRS durations do worse than those with normal QRS durations after hospitalization for heart failure, according to a recent study.

Researchers from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) performed a retrospective post hoc analysis to determine whether duration of QRS interval predicted outcomes in patients hospitalized for heart failure with decreased left ventricular ejection fraction (LVEF). The study involved 2,962 patients, 1,641 with normal QRS durations at baseline (defined as <120 ms) and 1,321 with prolonged QRS durations at baseline (defined as Ž120 ms). The study's primary end points were death from all causes and cardiovascular death or hospitalization for heart failure. Patients were followed for a median of 9.9 months. The study appeared in the June 11 Journal of the American Medical Association.

Patients with prolonged QRS duration were more likely to be older and male, have lower LVEF and systolic blood pressure, and have higher levels of serum brain natriuretic peptide and serum urea nitrogen. During the follow-up period, patients in the normal group had lower rates of all-cause mortality (18.7% vs. 28.1%; hazard ratio, 1.61 [95% CI, 1.38 to 1.87]) and cardiovascular death or heart failure hospitalization (32.4% vs. 41.6%; hazard ratio, 1.40 [95% CI, 1.24 to 1.58]) than those in the prolonged group. These increased risks persisted after adjustment for multiple variables.

The authors acknowledged several limitations of their study, including its post hoc design and the lack of information available about QRS duration before study enrollment. However, they concluded that patients hospitalized for heart failure with reduced LVEF often have prolonged QRS intervals and that this variable indicates high rates of morbidity and mortality after discharge, even when optimal therapy is provided. The authors called for future studies to determine whether cardiac resynchronization therapy with or without an implantable cardioverter defibrillator would improve outcomes in this group.