Weekend Discharge Not Linked to More Readmissions After Cardiac Surgery

Shipping a cardiac surgery patient home on the weekend or a holiday does not result in a higher rate of rehospitalization when compared with discharging patients during the week, according to the results of a new study.

Among 4,877 patients discharged from a large US center following cardiac surgery, nearly one in five were discharged on a Saturday, Sunday, or holiday, and 11.4% of these patients were readmitted to the hospital at 30 days. In contrast, 10.9% of patients discharged Monday through Friday were rehospitalized at 30 days, a nonsignificant difference between the two cohorts.

Yas Sanaiha, MD, who led the study with senior investigator Peyman Benharash, MD (both University of California, Los Angeles), said their center has implemented a multidisciplinary team approach aimed at proactive discharge education and this likely explains why they observed no difference in readmission rates. 

“The fact that there’s more staff on the day the patient is going home is not going to make a difference,” Sanaiha told TCTMD. “Rather it’s going to be a bundle of preparation that starts on postoperative day one or two, to work together with the family to set up the resources and expectations for when they do go home.”

The “weekend effect,” a phenomenon where weekend admissions have been shown to be associated with an increased risk of mortality, has been demonstrated across a range of clinical conditions. As part of their study, the investigators wanted to turn the question around to determine if discharging a patient on a weekend (or holiday) was also associated with increased risks.

“We were thinking that because the [index] hospitalization is such a high-intensive process, it might also lend itself to being vulnerable to the weekend effect,” said Sanaiha. On the weekend, for example, staff turnover is higher and fewer physicians are available, while individuals might have limited access to outpatient clinics or pharmacies. “All of these things taken together, we were worried it might lead to increased readmissions,” said Sanaiha.

No Weekend Effect With Discharge

The new study, which was published online ahead of print October 11, 2018, in the Annals of Thoracic Surgery, included patients from their center in the Society of Thoracic Surgeons (STS) registry who underwent any cardiac operation between 2008 and 2016 and excluded patients who underwent emergent or transplant surgery, received a ventricular assist device, or required extracorporeal membrane oxygenation support.

At 30 days, 11.3% of patients were readmitted to hospital, with nearly 40% of readmissions related to the primary surgery. Approximately 20% of patients were readmitted for cardiac disorders, including arrhythmia/heart block, pericardial effusion, or tamponade. Previous analyses have suggested that readmission after cardiac surgery is quite variable, ranging from 8% to 22% depending on the study period and patient and/or hospital demographics, said Sanaiha.

The researchers did not observe a weekend effect with respect to discharge and 30-day readmission rates. In this patient population, comorbidities previously associated with higher rates of readmission—older age, chronic obstructive lung disease, dialysis, postoperative pleural effusion, and neurobiologic complications—were also not associated with a higher rate of readmission. Smoking and preoperative beta-blocker use were linked with a higher risk of readmission at 30 days, although Sanaiha said beta-blocker use is likely a reflection of increased cardiovascular disease burden (and not the cause of the readmissions).   

Cardiac surgeon Richard Whitlock, MD (McMaster General Hospital, Hamilton, Canada), who was not involved in the study, said readmission after cardiac surgery is a critical issue and efforts to reduce the risk are appreciated. He was cautious, however, in his interpretation of the data, noting this was a single-center observational analysis. He pointed out that patients discharged during the week were sicker patients with more complications and a greater incidence of cerebrovascular disease, chronic lung disease, and diabetes, as well as more prolonged intubation and time spent in the ICU.

“It makes sense to me,” said Whitlock. “If I’m at the hospital on the weekend, and I’m the lone doctor covering the service, I’m less likely to discharge a more complex patient on the weekend than on a weekday. I’m probably a little nervous that I don’t have a good handle on this patient and I probably shouldn’t discharge them on a Saturday. Those sicker patients tend to get discharged on the weekday because everything is in place.”

And while the researchers adjusted for confounding variables, “the issue is that there’s known confounders, but there’s other aspects they’re not capturing,” said Whitlock. Patients who might be frailer or weaker, or those not mobilizing well, aren’t going to be discharged on a weekend based on the physician’s judgement, and these types of confounding variables aren’t accounted for in the analysis, he said.

Conducting a clinical trial randomizing patients to weekday versus weekend discharge would likely be too challenging, said Whitlock. That said, a prospective, observational study focused specifically on day of discharge could address the question. The present study is limited by data captured by the STS registry, but other measures, such as mobility and frailty, could be built into future prospective studies, he said.

UCLA Discharge Protocols

Of the 97.5% of patients who survived to discharge, the vast majority were discharged home and 13.2% were transferred to acute rehabilitation, an intermediate hospital, or a nursing home. The rate of readmission at 30 days was significantly higher for patients discharged to a facility than for those discharged home (14.3% vs 10.8%; P = 0.01), but in the fully adjusted risk model discharge to a facility other than home was not associated with an increased risk of readmission (OR 1.15; P = 0.36).   

At UCLA, a dedicated discharge educator is now available to speak with patients about optimal postoperative care and nurses work closely with the nurse practitioner to prepare the patient for discharge, said Sanaiha.

“It’s a variety of things that in our experience doesn’t necessarily point to the very last day the patient is in the hospital,” said Sanaiha. “It’s about patient and family preparation, connection, and familiarity with how to get in contact with the care team.” In addition, providing discharged patients and their families with an avenue to communicate any issues or concerns with physicians and nurses is important as is getting access to necessary medications, said Sanaiha. 

To TCTMD, Whitlock said the discharge protocol in place at UCLA appears to be doing an excellent job in preparing the patients to go home and that patients aren’t at risk when discharged on the weekend. But such a discharge service is not the norm around the country, he added. “It’s great that they’re having these results, but we have to be cautious in applying these results to hospitals without these proactive discharge plans.”

At Hamilton General Hospital, physicians are currently participating in research assessing the effectiveness of allowing trained nurses to remotely monitor vital signs of postoperative cardiac and vascular patients. Known as SMARTVIEW (Technology-Enabled Remote Monitoring and Self-Management: Vision for Patient Empowerment), the system allows nurses to receive real-time physiologic notifications from a patient’s remote automated monitoring device. 

“With any red flags that come up, they will contact the on-call surgeon, or the patient’s surgeon if it’s during the work day,” said Whitlock. “I think for the future of perioperative care, this is essential. There are good proportion of patients discharged home who do not do well because that first 30 days after surgery is a very high-risk period.”