Bedside sitters, pneumothorax, and more

Research summaries from ACP Hospitalist Weekly.

Little evidence to show whether bedside sitters reduce inpatient falls, review finds

There is scant evidence that bedside sitters reduce falls among hospital patients compared to usual care or alternative interventions, according to a recent review.

Researchers found 20 English-language studies that assessed the effect of adding sitters to usual care (two studies) or compared alternatives to sitters (18 studies) for adult patients on general wards of acute care hospitals. None of the studies were randomized, 11 were time-series studies, one was a retrospective quasi-experimental study, and eight were pre-post studies. The review was published by Annals of Internal Medicine on Feb. 4 and appeared in the March 3 issue.

Image by Getty Images
Image by Getty Images

Analysis of the two studies of adding sitters provided very low-certainty evidence that this intervention reduced falls compared to usual care. Those studies had conflicting results and took place in Australian hospitals with baseline fall rates three to four times higher than typical in the U.S., the reviewers noted. Eight studies provided moderate-certainty evidence that video monitoring interventions reduced sitter use and either did not affect or reduced the number of falls. Three studies looked at nurse assessment tools and two focused on close observation units, overall providing very low-certainty evidence that these interventions were effective alternatives to sitters. All of the studies had at least one methodological limitation, and none had low risk of bias.

The review's greatest limitation was the quantity and quality of the included studies, none of which tested sitters versus usual care in settings similar to U.S. hospitals, the authors said. They noted it might be difficult to get such evidence. “The use of 1-to-1 sitters may be so ingrained into usual care that a randomized trial comparing sitter use versus no sitter use may not be feasible,” the authors wrote, noting that comparisons of different interventions might be more likely. “Despite the lack of evidence, the rationale for the use of sitters to prevent falls is compelling, and it seems premature to conclude that their use should be abandoned.”

An accompanying editorial, by a geriatrician, said that sitters are one of her “backbone recommendations” for older inpatients with frailty or cognitive issues. The lack of evidence for them is “disconcerting,” the editorial said. The editorialist recommended that hospitals continue to use sitters while additional research is done but also “begin shifting the focus of our efforts and resources to identifying highly effective and lower-cost approaches to preventing falls and to making our health care facilities and treatments safer and more evidence-based on a broader scale.”

Health systems investing in social determinants of health, encountering barriers to success

Health systems in the U.S. have been investing substantial amounts of money to address social determinants of health, but early efforts have found a number of obstacles, according to two recent studies.

Both studies were published in the February Health Affairs. The first quantified new direct financial investments in social determinants of health announced by U.S. health systems from Jan. 1, 2017, to Nov. 30, 2019. It found 78 unique programs involving 57 health systems with a total of 917 hospitals. The programs involved at least $2.5 billion in spending. Housing-related interventions were the most common focus, with $1.6 billion committed by 52 programs. Additional focus areas included employment (28 programs, $1.1 billion), education (14 programs, $476.4 million), food security (25 programs, $294.2 million), social and community context (13 programs, $253.1 million), and transportation (six programs, $32 million).

Researchers also looked at investment by hospital characteristics and found significant differences. “The clear predominance of sectarian and other nonprofit institutions in making these investments and the absence of for-profit institutions suggest that health systems may be driven to invest in social determinants more by mission and values than by the potential for direct financial returns. However, the fact that investments are disproportionately being made by systems that are in Medicaid expansion states, in the [Bundled Payments for Care Improvement] BPCI Initiative, or in an [accountable care organization] ACO suggests that business-case considerations may also be playing a role,” the authors said. They noted that an ongoing challenge to these projects is that the evidence that social interventions improve health outcomes “is thin.”

The second study identified additional obstacles to improving social determinants of health in an analysis of 22 ACOs that were working on initiatives to address social needs including transportation, housing, and food. It found that health systems often lacked data on both their patients' social needs and the capabilities of potential community partners. In addition, relationships with these partners were in the early stages of development and often driven by personal relationships. Despite these limitations, referral to social services was more common than direct provision of them by the health systems.

The results show that “the tools at ACOs' disposal to integrate social services are weak, relative to the challenges of deeply entrenched social inequalities, siloed medical care and social services, and the long period of time needed to realize benefits from this work,” the authors said. “Policies that could facilitate the integration of social determinants include providing sustainable funding, implementing local and regional networking initiatives to facilitate partnership development, and developing standardized data on community-based organizations' services and quality to aid providers that seek partners.”

Conservative management appears safe, effective for some cases of spontaneous pneumothorax

Conservative management of spontaneous pneumothorax may be a safe and effective option in some patients versus interventional management, according to a recent study.

In an open-label, multicenter noninferiority trial, patients with a first episode of unilateral, moderate-to-large primary spontaneous pneumothorax were randomly assigned to immediate interventional management or conservative observation. Those in the intervention group received a procedure to reexpand the lung, were monitored by chest radiograph, and were admitted to the hospital if the initial attempt did not succeed or if the pneumothorax recurred after four hours of observation. Those in the conservative group were observed for at least four hours before repeated chest radiography and were discharged with analgesia and written instructions if they were not receiving supplementary oxygen and could walk comfortably. Patients in the conservative group could receive interventions under certain prespecified conditions. Follow-up was 12 months, and lung reexpansion within eight weeks was the primary outcome. The results of the trial were published Jan. 30 by the New England Journal of Medicine.

Three hundred sixteen patients were randomly assigned to either the intervention group or the conservative group. Of the 154 patients in the intervention group, 10 (6.5%) declined an intervention and received conservative care. Of the 162 patients in the conservative group, 25 (15.4%) received an intervention to manage pneumothorax based on reasons prespecified in the study protocol, and 137 (84.6%) received no interventions. Lung reexpansion within eight weeks occurred in 129 of 131 patients (98.5%) in the intervention group and 118 of 125 patients (94.4%) in the conservative group (risk difference, −4.1 percentage points; 95% CI, −8.6 to 0.5 percentage point; P=0.02 for noninferiority) in a complete-case analysis in patients for whom all data were available. The lower bound of the 95% CI was within the prespecified noninferiority margin (−9 percentage points). In a sensitivity analysis, all data missing after 56 days were imputed as treatment failure. One hundred twenty-nine of 138 patients (93.5%) in the intervention group and 118 of 143 patients (82.5%) in the conservative group had lung reexpansion within eight weeks, with a risk difference of −11.0 percentage points (95% CI, −18.4 to −3.5 percentage points). Risk for serious adverse events or recurrence of pneumothorax was lower with conservative than with interventional management.

In addition to an inability to mask group assignments and other limitations, the authors stressed that the original plan for statistical analysis did not include a specific window for the later follow-up visit and did not define how to handle missing radiographic data for the primary outcome. “These issues were important, because 22 patients who did not have resolution at their 4-week visit had resolution at the time of their scheduled 8-week visit, which occurred after 56 days,” they wrote. Although they adjusted for these factors in their analyses, the results should be considered exploratory, the authors noted. They concluded that their trial provides modest evidence that these two methods of management are noninferior for the primary outcome and that conservative management resulted in fewer hospital days, lower surgery rates, and lower risk of severe adverse events, among other benefits.

An accompanying editorial acknowledged the trial's limitations but said that “the basic point is that the conservative-management group did well” and that this approach appears safe. “On the basis of this randomized trial and the earlier reports, we should now be prepared to offer this conservative approach to the young, healthy person with a large primary spontaneous pneumothorax if there is no hemodynamic compromise and with the following provisos: the patient is informed and agrees to the approach, is readily available for outpatient follow-up, and is not planning air travel or scuba diving,” the editorialist wrote. “It is time to incorporate these findings into new guidelines to help standardize the approach across continents.”

EDs may be overtesting patients with suspected PE, study finds

A recent study of 27 EDs found a high use of CT pulmonary angiography scanning, including in young women, but a low yield rate for pulmonary embolism (PE).

Researchers used electronic health record and billing data for 16 EDs in Indiana and 11 in the Dallas-Fort Worth area from 2016 to 2019 to look at ED patients who had any of the following tests: D-dimer, CT pulmonary angiography, scintillation ventilation-perfusion lung scanning, or formal pulmonary angiography. The primary outcomes were ED encounter volume-adjusted CT pulmonary angiography rate and PE yield rate, with subgroup reporting for children and women younger than age 45 years. Results were published Jan. 20 by Circulation: Cardiovascular Quality and Outcomes.

Of about 1.8 million patient encounters, 97,125 (5.3%) had a diagnostic test for PE. Overall, 53,252 (55%) patients had D-dimer testing only, and 42,267 (44%) patients had a CT pulmonary angiography order, including 17,397 who also had a D-dimer test and 24,870 who did not. The yield rate for PE from CT pulmonary angiography scans was 1.3% (1.1% to 1.5%) in Indiana and 4.8% (4.2% to 5.1%) in Dallas-Fort Worth (pooled rate, 3.1%). Linear regression showed that increased D-dimer ordering correlated with increased PE yield rate (Pearson's R2=0.43; P<0.001). Overall, 59% of the CT pulmonary angiography was done in women, with 21% done in women younger than age 45 years. The most frequent diagnoses were symptom-based descriptions of chest pain (34%) and shortness of breath (6.5%) and condition-based diagnosis of pneumonia (4.1%).

The study was limited by its use of ICD-10 coding data, which may have underestimated the true rate of PE diagnosis and/or contained false-positives, the authors said. They added that the data did not allow insight into why CT pulmonary angiography scans were ordered, and it is possible that clinicians were not always searching for PE.

“The D-dimer was used in less than half of patients with CT [pulmonary angiography] and in centers with higher D-dimer usage, the yield rate for PE was higher,” they concluded. “These data show the urgent need for dissemination and implementation of protocols to reduce low-yield CT [pulmonary angiography] scanning.”

Recent heart failure readmission and mortality trends differ in U.S., Canada

In Canada, readmission rates and postdischarge mortality have declined among patients hospitalized with acute myocardial infarction or heart failure in recent years, a recent analysis found.

Image by Getty Images
Image by Getty Images

The study included patients 65 years of age or older who had been hospitalized in Ontario in 2006 to 2017 with either acute myocardial infarction (n=152,808) or heart failure (n=223,283). The authors analyzed the data with the same risk-adjustment methods used to evaluate the Hospital Readmissions Reduction Program (HRRP) in the U.S. Results were published in the Feb. 25 Journal of the American College of Cardiology.

When standardized for age and sex, overall hospitalization rates in Ontario declined for both conditions (32% decline from 2006 to 2017 for myocardial infarction, 9.1% decline for heart failure). For acute myocardial infarction patients, risk-adjusted 30-day readmission rates dropped from 17.4% to 14.7% and 30-day post-discharge mortality decreased from 5.1% to 4.4%. Readmission rates for heart failure were largely unchanged from 2006 to 2014 at 21.9%, but then declined to 20.8% in 2017. Mortality in the 30 days after heart failure discharge declined from 7.1% in 2006 to 6.6% in 2017.

“The findings contrast with results reported from the United States,” the study authors said, noting that in the same time period, U.S. heart failure admissions and readmissions dropped significantly and postdischarge mortality increased. “The reasons underlying the diverging country-specific patterns for patients with [heart failure] HF are not clear, but should be concerning for the United States, who have had a trend of increasing post-discharge HF mortality since 2006 which preceded the readmission program,” they wrote.

It is difficult to compare heart failure mortality trends across the two countries, the authors noted. Other limitations of the study include uncertainty about why the countries had similar results for acute myocardial infarction but not heart failure and how increasing hospital crowding in Ontario might have affected the findings.

An accompanying editorial comment described the many difficulties in determining the effects of programs like the HRRP. “This new work will not resolve the debate on HRRP and mortality. But it should move the needle to focus more on health policy and care delivery in the United States,” the editorialist wrote. A major focus should be increasing use of goal-directed medical therapy for heart failure, possibly with targeted payment incentives. “After all, if there's one thing we should all agree on about HRRP, it's that large financial incentives can focus attention,” the editorial concluded.

Machine learning model identified predictors of in-hospital mortality on admission

A machine learning model demonstrated good discrimination of in-hospital mortality for adult patients at the time of admission in a recent validation study at multiple hospitals.

Researchers at Duke University Health System in North Carolina trained the model using electronic health record (EHR) data from 43,180 hospitalizations of 31,003 unique adult patients admitted to one system hospital (hospital A) from Oct. 1, 2014, to Dec. 31, 2015. They built a total of 195 model features using 57 EHR data elements, including patient demographic characteristics (five data elements), laboratory test results (33 data elements), vital signs (nine data elements), and medication administrations (10 data elements) that were available between hospital presentation and time of admission. A dashboard displayed patient risk scores to clinicians. The study evaluated the model in retrospective and prospective validation cohorts in three hospitals at the health system. All hospitalizations of adult patients with an order placed for inpatient admission were included (including those who died in the ED after such an order was placed).

The model was retrospectively and temporally validated in a separate cohort of 16,122 hospitalizations of 13,094 patients admitted to hospital A from March 1 to Aug. 31, 2018. It was also retrospectively and externally validated using two separate cohorts from two different community-based hospitals. Hospital B had a cohort of 6,586 hospitalizations of 5,613 patients, and hospital C had a cohort of 4,086 hospitalizations of 3,428 patients, all occurring from March 1 to Aug. 31, 2018. Then the model was integrated into the EHR and prospectively validated in a cohort of 5,273 hospitalizations of 4,525 patients admitted to hospital A from Feb. 14 to April 15, 2019. The main outcome was in-hospital mortality (defined as a discharge disposition of “expired”), and model performance was quantified using the area under the receiver operating characteristic curve (AUROC) and area under the precision recall curve (AUPRC). Results were published online Feb. 7 by JAMA Network Open.

Overall, the study included 75,247 hospitalizations (median patient age, 59.5 years; 45.9% involving male patients), 2,021 (2.7%) of which resulted in in-hospital mortality. The in-hospital mortality rates for the training validation; retrospective validations at hospitals A, B, and C; and prospective validation cohorts were 3.0%, 2.7%, 1.8%, 2.1%, and 1.6%, respectively. The AUROCs were 0.87 (95% CI, 0.83 to 0.89), 0.85 (95% CI, 0.83 to 0.87), 0.89 (95% CI, 0.86 to 0.92), 0.84 (95% CI, 0.80 to 0.89), and 0.86 (95% CI, 0.83 to 0.90), respectively. The AUPRCs were 0.29 (95% CI, 0.25 to 0.37), 0.17 (95% CI, 0.13 to 0.22), 0.22 (95% CI, 0.14 to 0.31), 0.13 (95% CI, 0.08 to 0.21), and 0.14 (95% CI, 0.09 to 0.21), respectively.

The 2018 temporal and external validation cohorts showed that if the model were implemented in each setting at a threshold that corresponds to a sensitivity (recall) of 60%, the positive predictive value would be 9.8% in hospital A, 8.0% in hospital B, and 9.1% in hospital C. In the prospective validation cohort, using a threshold that corresponds to a sensitivity of 60% would lead to a positive predictive value of 8.5%.

The results may not be generalizable to hospitals in other regions and were due in large part to the institution's technology infrastructure, among other limitations, the study authors noted. They added that the model should not be used to prioritize patients for admission to the ICU or to limit care delivery.

“While we demonstrate that the model prediction accuracy is maintained prospectively, it is unknown whether these predictions will actually improve clinical or operational outcomes. Future work will evaluate the implementation of a clinical workflow,” they wrote, adding that the first use they plan to evaluate is identification of patients for palliative care consultation.