ABSTRACT
This study was planned to evaluate the clinical features and outcomes of patients hospitalized in intensive care units (ICUs) on-hours [workdays (WD)] and out of hours [time-off (TO)].
Ethics committee approval was obtained for this study. Patients hospitalized in adult ICUs between July 2021 and January 2022 were retrospectively evaluated. The patients were divided into two groups: those who were accepted during on-hours (group WD, WD 08.00 am-05.00 pm) and out of hours (group TO; WD-05.01 pm-07.59 am, weekends, and all public holidays). The groups were compared in terms of patient characteristics and intensive care outcomes.
Of the 173 patients included in the study, 69.94% (n=121) were hospitalized during out-of-hours and 30.05% (n=52) during on-hours. The median age of the patients was 70.3±9.5 years, 58.4% were male and 41.6% were female. The number of patients hospitalized in TO was statistically significantly higher than the number of patients in WD (p=0.04). There was no significant difference between the two groups in terms of demographic data, except that chronic renal failure (18.2%, p=0.024) was more common as a comorbidity in TO patients. The need for continuous renal replacement therapies treatment, which is one of the reasons for ICU admission, was found to be significantly higher in TO patients (p=0.048). The length of stay in the ICU and intubation period was higher in group TO (p=0.006, p=0.022). It resulted in death in 34.1% of the patients. There was no significant difference in mortality and discharge between the groups.
In our study, the clinical outcome was found to be similar in patients followed up in ICUs under WD and TO conditions. This result; This can be attributed to the fact that the shift team is not different in our hospital, the number of experienced health personnel is high, and the necessary diagnostic procedures are not delayed.
Keywords: Intensive care unit, working hours, workdays, time-off, mortality, discharge
Introduction
Intensive care units (ICU); are clinics where critically ill patients are treated with a multidisciplinary approach. Situations that require close observation and rapid intervention may develop during patient follow-up. Although mortality rates in the ICUs vary depending on the underlying disease, they are usually higher than in other services of the hospital. Mortality rates tend to decrease in ICUs, especially with the training of qualified personnel and the presence of technological developments (mechanical ventilation, extracorporeal membrane oxygenation, continuous renal replacement, etc.).
In the literature, there are many studies that show that clinics work more effectively during weekdays than weekends (1-3). Some researchers have suggested that this relationship is causal and is due to weekend reductions in hospital staff and/or the fact that out-of-hours staff generally have less seniority and experience than regular-time workers. Others have argued that this correlation is due to unobservable characteristics of hospitalized patients. It is important to provide the same quality of service in ICUs 24/7 for the prognosis of the patient. As a result, in this study, our primary aim is to evaluate the outcomes of patients hospitalized in ICUs out of hours and our secondary aim is to determine the factors affecting mortality.
Materials and Methods
Study Design and Participants
This retrospective cohort study was carried out in a single 10-bed ICU of a city hospital operating with 90 intensive care beds. After obtaining the University of Health Sciences Turkey, Kartal Dr. Lütfi Kırdar City Hospital Clinical Research Ethics Committee approval (decision no: 2022/514/218/8, date: 28.01.2022) and informed consent from all patients, data was started to collect by scanning the electronic system and patient files. The study was carried out in accordance with the ethical principles stated in the Declaration of Helsinki and Good Clinical Practices.
The study included 173 adult patients who were hospitalized in the tertiary level ICU between July/2021 and January/2022. The patients were divided into two groups as those who were accepted during on-hours [group workdays (WD); weekdays 08:00 am-05:00 pm] and those who were accepted out-of-hours [group time-off (TO); weekdays 05.01 pm-07.59 am, weekends and all public holidays].
Data Collection
The clinical and demographic characteristics of the patients, the reasons of hospitalization, accompanying comorbidities, the number of days intubated, the length of stay in ICU, discharge and death status were recorded. Patients hospitalized for postoperative follow-up and patients who were hospitalized for less than 24 hours were excluded from the study. The groups were compared in terms of patient characteristics and intensive care outcomes.
Intervention
The primary predictor was whether the admission was on a during working hours or out of hours.
Measurement
The primary outcome was in ICU mortality and secondary outcomes were discharge and length of stay.
Statistical Analysis
All statistical analyses were performed using the SPSS (Statistical Package for Social Sciences) software, version 21.0 (IBM Corp., Armonk, NY). Quantitative variables expressed as mean ± standard deviation, were compared using the Student’s t-test. The qualitative variables were expressed in percentages and compared using either the chi-square test or Fisher’s Exact test. A p-value <0.05 was considered significant.
Results
In the study period, 121 (69.94%) patients in group TO and 52 (30.05%) patients from group WD were included into the study. Number of patients hospitalized outside of working hours were significantly higher than hospitalized during working hours (p=0.04). The median age of these 173 patients was 70.3±9.5 years, 58.4% male and 41.6% female. There was no significant difference between the two groups in terms of comorbidity, except that chronic renal failure (CRF). CRF was significantly higher in group TO than in group WD (p=0.024) (Table 1).
The number of patients receiving invasive mechanical ventilation support was similar in the two groups. However, length of stay in ICU and intubated days were found to be significantly higher in group TO (p=0.006, p=0.022) and the need for continuous renal replacement therapies treatment was found to be significantly higher in group TO (p=0.048) (Table 2).
A total of 59 (34.1%) patients died in ICU. Of these, 15 (32.7%) belonged to group WD, 44 (35.5%) belonged to group TO, and there was no significant difference between the groups in mortality (p=0.429). A total of 65.9% of the patients were discharged from ICU. There was no significant difference in the number of discharged patients between the groups (Table 2).
Discussion
In this study, we examined the hospitalization of patients in ICUs for a period of 6 months. We found that the number of patients hospitalized out of hours was higher than those hospitalized during working hours, but there was no significant difference between the two groups in terms of discharge from ICU and mortality. This result may reflect that there is no difficulty in accessing in-hospital care during non-working hours. When the literature is searched, there are many studies showing that hospital admission during out-of-hours is associated with higher in-hospital mortality rates (1-3), but the reasons for this phenomenon is controversial.
As a result of a 10-year study, Bell and Redelmeier (4) concluded that the mortality rate is high in weekend inpatients and that this result is unlikely to be due to chance, with the exact binomial distribution. They attributed the high causes of death to the unpopularity of working on the weekends, the lack of equal numbers and skills of staff working on the weekends, and also the fact that there are fewer supervisors on weekends. In our study; in the ICU, the same team and the same number of ICU staffing work during working hours and on the shifts. We believe that this situation is effective on equalizing the quality of work. Similarly, Fan and Needham (5) supported this conclusion with their study.
Laupland et al. (6), in their study, found that 41% of the patients hospitalized in the ICU were overnight and 49% were overnight and/or weekends, and they emphasized that overnight stay was associated with mortality. Similarly, Buck et al. (7) evaluated the relationship between patient admission to the ICU out of hours and on the weekend, and 90-day mortality and showed that the risk of death in adult patients was slightly higher in those hospitalized out of hours; as in our study, emphasized that increasing the out-of-hours services may result in the desired decrease in the inpatient mortality rate.
Halm and Chassin (8) raised the question of why hospital mortality rates are changing, and they argued that this situation is based on medical-social-biological procedural knowledge and therefore deserves careful investigation.
In a meta-analysis of forty-five articles by Honeyford et al. (9) concluded that there is high heterogeneity for the “weekend effect” and further studies are needed. In a comprehensive meta-analysis by Hoshijima et al. (10); they concluded that although weekend admissions were associated with a higher risk of death than weekday admissions, this effect was limited to certain diagnostic groups and admission subtypes. As can be seen, the relationship between patient prognosis and admission time is limited and shows quite heterogeneity. In this study, we observed that a similar population of patients were admitted to our hospital during the day and night. Mitchell et al. (11) examined a similar study on a specific population. They cohort 3,729 adult stroke patients hospitalized in tertiary care between 2001 and 2012. As a result of that study; the effect of weekend ICU-admission for stroke patients appears to be significant for in-hospital mortality, but no significant difference in adjusted ICU-mortality, length-of-stay, or longer-term morbidity and mortality measures (11).
On the other hand, Adıgüzel et al. (12) concluded in their study that full-time staff would improve outcomes in the ICUs. In a recent study, Aiken et al. (13) showed that nurse employment and education are effective on patient mortality. In our study, only the patients hospitalized in the ICU were evaluated and the training of the personnel as a single unit was based on.
Barnett et al. (14) conducted a study in 38 ICUs in 28 hospitals, reported that the length of stay in the ICU was significantly longer for weekend or Friday admissions. Ko et al. (15) showed that there was a significant increase in weekend hospital admissions, mortality rate, and length of stay. Similarly, in the present study, length of stay in the ICU and intubation period were found to be longer in patients in group TO. This may be associated with unmeasured factors such as patient characteristics and the severity of the disease. This result suggests that the patient risk profile and a difference in severity of illness greatly affect the course of the disease from patient to patient even if it does not change the outcome.
In present study, we aimed to investigate whether there is a difference in patient outcomes in patients admitted to the ICUs out of hours compared to patients hospitalized during working hours, and we found that mortality rates did not change when full care and support can be provided. Discharge rates were also similar. We attributed this situation to the fact that the patients who admitted to the hospital during and out of hours had a similar profile in terms of factors that could affect mortality and that they could receive similar health care independent of working hours. Differences in patient risk factors and disease severity affected the process, but did not change the outcome.
The results of our study need to be interpreted within the context of its limitation. First, our study was a retrospective study and sample size was small. Secondly, our study did not account patient’s intrinsic factors and the severity of illness. Finally, we did not attempt to determine whether the outcomes were associated with qualities of care and weekend working staff in this study.
Conclusion
Numerous adverse prognostic factors have been described that affect mortality rates in critically ill patients admitted to the ICU. Our study showed that hospitalization of patients out-of-hours is not one of these reasons. Thus, we wanted to emphasize that the number of full-time personnel should be sufficient and the necessary diagnostic procedures should not be delayed.
Ethics
Ethics Committee Approval: After obtaining the University of Health Sciences Turkey, Kartal Dr. Lütfi Kırdar City Hospital Clinical Research Ethics Committee approval (decision no: 2022/514/218/8, date: 28.01.2022). The study was carried out in accordance with the ethical principles stated in the Declaration of Helsinki and Good Clinical Practices.
Informed Consent: Informed consent from all patients, data was started to collect by scanning the electronic system and patient files.
Peer-review: Externally peer-reviewed.
Authorship Contributions
Surgical and Medical Practices: Y.B., F.C., D.Ç., K.T.S., Concept: Y.B., Design: Y.B., K.T.S., Data Collection and Process: F.C., D.Ç., Analysis or Interpretation: Y.B., F.C., Literature Search: Y.B., D.Ç., K.T.S., Writing: Y.B.
Conflict of Interest: No conflict of interest was declared by the authors.
Financial Disclosure: The authors declared that this study received no financial support.
