Weekend versus weekday transplant surgery and outcomes after kidney transplantation in the USA: a retrospective national database analysis

Investigation of the weekend effect on perioperative complications and mortality after carotid revascularization

OBJECTIVE

Outcomes for weekend surgical interventions are associated with higher rates of mortality and complications than weekday interventions. Although prior investigations have reported the "weekend effect" for carotid endarterectomy (CEA), this association remains unclear for transcarotid artery revascularization (TCAR) and transfemoral carotid artery stenting (TFCAS). We investigated the weekend effect for all three carotid revascularization methods.

METHODS

We queried the Vascular Quality Initiative for patients who underwent CEA, TCAR, and TFCAS between 2016 and 2022. χ2 and logistic regression modeling analyzed outcomes including in-hospital stroke, death, myocardial infarction, and 30-day mortality by weekend vs weekday intervention. Backward stepwise regression was used to identify significant confounding variables and was ultimately included in each final logistic regression model. Logistic regression of outcomes was substratified by symptomatic status. Secondary multivariable analysis compared outcomes between the three revascularization methods by weekend vs weekday interventions.

RESULTS

A total of 155,962 procedures were analyzed including 103,790 CEA, 31,666 TCAR, and 20,506 TFCAS. Of these, 1988 CEA, 246 TCAR, and 820 TFCAS received weekend interventions. Logistic regression demonstrated no significant differences for TCAR and increased odds of in-hospital stroke/death/myocardial infarction for CEA (odds ratio [OR]: 1.31, 95% confidence interval [CI]: 1.04-1.65) and TFCAS (OR: 1.46, 95% CI: 1.09-1.96) weekend procedures. Asymptomatic TCAR patients had nearly triple the odds of 30-day mortality (OR: 2.85, 95% CI: 1.06-7.68, P = .038). Similarly, odds of in-hospital death were nearly tripled for asymptomatic CEA (OR: 2.89, 95% CI: 1.30-6.43, P = .009) and asymptomatic TFCAS (OR: 2.78, 95% CI: 1.34-5.76, P = .006) patients. Secondary analysis demonstrated that CEA and TCAR had no significant differences for all outcomes. TFCAS was associated with increased odds of stroke and death compared with CEA and TCAR.

CONCLUSIONS

In this observational cohort study, we found that weekend carotid revascularization is associated with increased odds of complications and mortality. Furthermore, asymptomatic weekend patients perform worse in the CEA and TFCAS procedural groups. Among the three revascularization methods, TFCAS is associated with the highest odds of perioperative stroke and mortality. As such, our findings suggest that TFCAS procedures should be avoided over the weekend in favor of CEA or TCAR. In patients who are poor candidates for CEA, TCAR offers the lowest morbidity and mortality for weekend procedures.

The weekend effect in kidney transplantation outcomes: A meta-analysis

OBJECTIVE

To determine whether kidney transplants performed during weekends have worse outcomes than those performed during weekdays.

METHODS

For this systematic review, PubMed, EMBASE, and the Cochrane Library (January 2000 to January 2023) were searched. We examined the survival rates of patients and grafts for hospital inpatients admitted during weekends and those admitted during weekdays. To be included, the study had to be in English and had to provide discrete survival data around weekends versus weekdays, including patients who were admitted as inpatients over the weekend.

RESULTS

Five studies (n = 163,506 patients) were examined. The hazards ratio (HR) of the survival rate of patients with weekend transplantation was 1.01 (95% confidence interval [CI], 0.96 to 1.06) when compared with patients with weekday transplantation. Patients who had renal transplant on weekends had an overall allograft survival HR of 1.01 (95% CI, 0.99 to 1.03) and death-censored allograft survival HR of 1.01 (95% CI, 0.98 to 1.04). Comparison of length of hospital stay, rejection, surgical complications, and vascular complications between renal transplants on weekends and those on weekdays showed no statistical difference.

CONCLUSION

Hospital inpatients admitted for renal transplantation during weekends have a survival rate similar to that of inpatients admitted during weekdays. The weekend effect of renal transplantation was very weak; hence, transplantations done during weekends and weekdays are both appropriate.

Variation of Liver Transplant Practice and Outcomes During Public Holidays in the United States: Analysis of United Network for Organ Sharing Registry

It has been reported that patients hospitalized outside regular working hours have worse outcomes. This study aims to compare outcomes following liver transplantation (LT) performed during public holidays and nonholidays.

Revisiting the "Weekend Effect" on Adult and Pediatric Liver and Kidney Offer Acceptance

BACKGROUND Weekends can impose resource and manpower constraints on hospitals. Studies using data from prior allocation schemas showed increased adult organ discards on weekends. We examined the impact of day of the week on adult and pediatric organ acceptance using contemporary data. MATERIAL AND METHODS Retrospective analysis of UNOS-PTR match-run data of all offers for potential kidney and liver transplant from 1/1/2016 to 7/1/2021 were examined to study the rate at which initial offers were declined depending on day of the week. Risk factors for decline were also evaluated. RESULTS Of the total initial adult/pediatric liver and kidney offers, the fewest offers occurred on Mondays and Sundays. The decline rate for adult/pediatric kidneys was highest on Saturdays and lowest on Tuesdays. The decline rate for adult livers was highest on Saturday and lowest on Wednesday. In contrast, the decline rate for pediatric livers was highest on Tuesdays and lowest on Wednesdays. Independent risk factors from multivariate analysis of the adult/pediatric kidney and liver decline rate were analyzed. The weekend offer remains an independent risk factor for adult kidney and liver offer declines, but for pediatric offers, these were not significant independent risk factors. CONCLUSIONS Although allocation systems have changed, and the availability of kidneys and livers have increased in the USA over the past 5 years, the weekend effect remains significant for adult liver and kidney offers for declines. Interestingly, the weekend effect was not seen for pediatric liver and kidney offers.

The liver transplant surgeon Mondays blues: an Italian perspective

Poor data exist on the influence of holidays and weekdays on the number and the results of liver transplantation (LT) in Italy. The study's main objective is to investigate the impact of holidays and the different days of the week on the LT number and early graft survival rates in a multi-centric Italian series. We performed a retrospective analysis on 1,026 adult patients undergoing first deceased-donor transplantation between January 2004 and December 2018 in the three university centers in Rome. During the 4,504 workdays, 881 LTs were performed (85.9%; one every 5.1 days on average). On the opposite, 145 LTs were done during the 975 holidays (14.1%; one every 7.1 days on average). Fewer LTs were performed on holidays (P = 0.004). There were no substantial differences in donor-, recipient- and transplant-related characteristics in LTs performed on weekdays or holidays. On Monday, fewer transplants were performed (vs. other weekdays: P < 0.0001; vs. Sunday: P = 0.03). At multivariable Cox regression analysis, LTs performed during the holiday or during the different days of the week were not found to be independent risk factors for the risk of 3- and 12-month graft loss. At three-month survival curves, no differences were observed among the transplants performed during the holidays versus the workdays (86.2 vs. 85.0%; P-0.70). The range of graft survival rates based on the day of the week was 81.6-86.9%, without showing any significant differences (P = 0.57). Fewer transplants are performed on holidays and Mondays. Survivals are not affected by holidays or the day the transplant is performed.

Timing of Kidney Clamping and Deceased Donor Kidney Transplant Outcomes

BACKGROUND AND OBJECTIVES

The fact that metabolism and immune function are regulated by an endogenous molecular clock that generates circadian rhythms suggests that the magnitude of ischemia reperfusion, and subsequent inflammation on kidney transplantation, could be affected by the time of the day.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We evaluated 5026 individuals who received their first kidney transplant from deceased heart-beating donors. In a cause-specific multivariable analysis, we compared delayed graft function and graft survival according to the time of kidney clamping and declamping. Participants were divided into those clamped between midnight and noon (ante meridiem [am] clamping group; 65%) or clamped between noon and midnight (post meridiem [pm] clamping group; 35%), and, similarly, those who underwent am declamping (25%) or pm declamping (75%).

RESULTS

Delayed graft function occurred among 550 participants (27%) with am clamping and 339 (34%) with pm clamping (adjusted odds ratio, 0.81; 95% confidence interval, 0.67 to 0.98; P=0.03). No significant association was observed between clamping time and overall death-censored graft survival (hazard ratio, 0.92; 95% confidence interval, 0.77 to 1.10; P=0.37). No significant association of declamping time with delayed graft function or graft survival was observed.

CONCLUSIONS

Clamping between midnight and noon was associated with a lower incidence of delayed graft function, whereas declamping time was not associated with kidney graft outcomes.

The weekday effect on postoperative mortality in elective abdominal surgery: An observational study using propensity score methods

BACKGROUND

Although the "weekday effect" may influence postoperative outcomes, controversies regarding its existence remain. The aim of this study was to investigate the association between the day of the week the surgery was performed and postoperative outcomes.

METHODS

Data from 58,646 patients who underwent elective abdominal surgery at Seoul National University Bundang Hospital from May 2003 to February 2018 were retrospectively analyzed. Two elective surgery groups comprising of 33,513 (57.1%) and 25,113 (42.9%) patients who underwent surgery in the early and late days of the week, respectively, were analyzed. Late days of the week was defined as days where surgery was performed within 2 days before weekends or holidays and early days of the week as all other weekdays. These groups were balanced using inverse probability of treatment weighting. The adjusted 30-day mortality and length of hospital stay were compared.

RESULTS

In the weighted sample, all 52 clinical covariates were comparable between the 2 groups. The weighted sample analysis did not reveal a significant difference in the 30-day mortality between early days of the week and late days of the week (0.19% early days of week vs 0.18% late days of the week; relative risk, 0.97; 95% confidence interval, 0.66-1.50; P = .82). Similarly, the median length of hospital stay showed no significant difference between the 2 groups (median value for both groups, 5.0 days; interquartile range 3.0-8.0; relative risk, 1.00; 95% confidence interval, 0.97-1.03; P = .16).

CONCLUSION

A weekday effect associated with the day of elective surgery performed was not found in this study for either the 30-day postoperative mortality or length of hospital stay.

Intra-aortic balloon pump placement in coronary artery bypass grafting patients by day of admission

INTRODUCTION

Intra-Aortic Balloon Pumps (IABPs) can be utilized to provide hemodynamic support in high risk patients awaiting coronary artery bypass grafting (CABG). There are many indications for IABP and institutional practice patterns regarding the placement of IABPs is variable. As a result, the preoperative placement of an IABP in a patient awaiting CABG is not standardized and may vary according to non-clinical factors. We hypothesize that the rate of IABP placement varies by day of the week.

METHODS

A retrospective cohort analysis of the Office of Statewide Health Planning and Development database from 2006 to 2010 was performed. All patients admitted for CABG were included. Patients who died within 24 h of admission and those who had absolute contraindications to IABP placement were excluded. The primary outcome was preoperative IABP placement versus non-placement. A multivariable logistic regression analysis to identify predictors of IABP placement was performed, adjusting for patient demographics, clinical factors, and system variables.

RESULTS

A total of 46,347 patients underwent CABG, of which 7695 (16.60%) had an IABP placed preoperatively. On unadjusted analysis, IABP rates were significantly higher on weekends versus weekdays (20.83% vs. 15.70%, p < 0.001). On adjusted analysis, patients awaiting CABG were 1.30 times more likely to have an IABP placed on weekends than on weekdays (OR: 1.30, 95% CI 1.20-1.40, p < 0.001).

CONCLUSION

The odds of preoperative IABP placement prior to CABG is significantly increased on weekends compared to weekdays, even when controlling for clinical factors. Further exploration of this phenomenon and its associations are warranted.

Weekend Carotid Endarterectomies are Not Associated with a Greater Risk of Stroke and/or Death in Australia and New Zealand

BACKGROUND

Data from multiple surgical studies and settings have reported an increase in adverse events in patients admitted or treated on weekends. The aim of this study was to investigate short-term outcomes for patients undergoing carotid endarterectomy (CEA) in Australia and New Zealand based on the day of surgery.

METHODS

This is a retrospective observational cohort study. Analysis of 7,857 CEAs recorded for more than 4 years in the Australasian Vascular Audit database was performed. Multivariate logistic regression was used to compare the following outcomes between CEAs performed during the week and on the weekend: (1) in-hospital stroke and/or death; (2) other postoperative complications; and (3) shorter (2 days or less) length of stay (LOS).

RESULTS

A total of 7,857 CEAs were recorded, with significantly more procedures performed during the week (n = 7,333, P < 0.001). There was no statistically significant difference in the frequency of stroke and/or death or other complications between CEAs performed during the week or on the weekend (P = 0.294 and P = 0.806, respectively). However, there was a significant difference in LOS for procedures performed during the weekend, with more of these patients being discharged within 2 days compared with procedures performed during the week (56.8% vs. 51.5%; P = 0.003). Multivariable logistic regression found no effect of day of the week on the odds of postoperative stroke and/or death (P = 0.685). Day of surgery was also not associated with greater odds of other complications (P = 0.925). However, CEAs performed by nonconsultants had significantly lower adjusted odds of other complications (3.1% vs. 4.1%; P = 0.033). The adjusted odds of having a shorter LOS were significantly greater for operations taking place on the weekend (P = 0.003).

CONCLUSIONS

In Australia and New Zealand, there appears to be no disadvantage to performing CEA on the weekend, in terms of stroke and/or death. Level of experience of the primary operator does not affect rates of stroke and/or death after CEA. Weekend CEA is associated with a shorter hospital LOS.

Weekend Effect and in-Hospital Mortality in Elderly Patients with Acute Kidney Injury: A Retrospective Analysis of a National Hospital Database in Italy

Background: The aim of this study was to relate the weekend (WE) effect and acute kidney injury (AKI) in elderly patients by using the Italian National Hospital Database (NHD). Methods: Hospitalizations with AKI of subjects aged ≥ 65 years from 2000–2015 who were identified by the ICD-9-CM were included. Admissions from Friday to Sunday were considered as WE, while all the other days were weekdays (WD). In-hospital mortality (IHM) was our outcome, and the comorbidity burden was calculated by the modified Elixhauser Index (mEI), based on ICD-9-CM codes. Results: 760,664 hospitalizations were analyzed. Mean age was 80.5 ± 7.8 years and 52.2% were males. Of the studied patients, 9% underwent dialysis treatment, 24.3% were admitted during WE, and IHM was 27.7%. Deceased patients were more frequently comorbid males, with higher age, treated with dialysis more frequently, and had higher admission during WE. WE hospitalizations were more frequent in males, and in older patients with higher mEI. IHM was independently associated with dialysis-dependent AKI (OR 2.711; 95%CI 2.667–2.755, p < 0.001), WE admission (OR 1.113; 95%CI 1.100–1.126, p < 0.001), and mEI (OR 1.056; 95% CI 1.055–1.057, p < 0.001). Discussion: Italian elderly patients admitted during WE with AKI are exposed to a higher risk of IHM, especially if they need dialysis treatment and have high comorbidity burden.

The weekend effect in kidney transplantation outcomes: a French cohort-based study

Numerous studies have reported a weekend effect on outcomes for diseases treated at hospitals. No study has been conducted in France for kidney transplantation. We therefore performed a cohort-based study to evaluate whether outcomes of kidney transplant recipients display a weekend effect. Data were extracted from the French DIVAT cohort. Patients aged 18 years and older, transplanted with a single kidney from deceased donors between 2005 and 2017 were studied. Linear regression, logistic regression, and cause-specific Cox model were used. Among the 6652 studied patients, 4653 patients were transplanted during weekdays (69.9%) versus 1999 during weekends (30.1%). The only statistically significant difference was the percentage of patients with vascular surgical complication(s) at 30 days: 13.3% in the weekend group versus 16.2% in the weekday group 0.79 (95% CI: 0.68; 0.92). We did not observe other significant differences for the other outcomes: patient or graft survival, the risk of acute rejection episodes, the 30-day percentage of urological complications, and the 1-year estimated glomerular filtration rate. Our study highlights a small protective weekend effect with less post-surgery vascular complications compared to weekdays. This paradox might be explained by a different handling of weekend transplantations.

Assessment of the "Weekend Effect" in Lower Extremity Vascular Trauma

BACKGROUND

Studies suggest that patients admitted on weekends may have worse outcomes as compared with those admitted on weekdays. Lower extremity vascular trauma (LEVT) often requires emergent surgical intervention and might be particularly sensitive to this "weekend effect." The objective of this study was to determine if a weekend effect exists for LEVT.

METHODS

The National and Nationwide Inpatient Sample Database (2005-2014) was queried to identify all adult patients who were admitted with an LEVT diagnosis. Patient and hospital characteristics were recorded or calculated and outcomes including in-hospital mortality, amputation, length of stay (LOS), and discharge disposition were assessed. Independent predictors of outcomes were identified using multivariable regression models.

RESULTS

There were 9,282 patients admitted with LEVT (2,866 weekend admissions vs. 6,416 weekday admissions). Patients admitted on weekends were likely to be younger than 45 years (68% weekend vs. 55% weekday, P < 0.001), male (81% weekend vs. 75% weekday, P < 0.001), and uninsured (22% weekend vs. 17% weekday, P < 0.001) as compared with patients admitted on weekdays. There were no statistically significant differences in mortality (3.8% weekend vs. 3.3% weekday, P = 0.209), amputation (7.2% weekend vs. 6.6% weekday, P = 0.258), or discharge home (57.4% weekend vs. 56.1% weekday, P = 0.271). There was no clinically significant difference in LOS (median 7 days weekend vs. 7 days weekday), P = 0.009. On multivariable regression analyses, there were no statistically significant outcome differences between the groups.

CONCLUSIONS

This study did not identify a weekend effect in LEVT patients in the United States. This suggests that factors other than the day of admission may be important in influencing outcomes after LEVT.

Survival Outcomes Are Not Affected When Liver Transplant Surgery Is Done at Night, During Weekends, or Summer Months

Background

It has been suggested that hospitalized patients may get suboptimal care in nights or on weekends or summer holidays due to sleep deprivation, physician fatigue, or reduced medical staffing. Our objective was to determine whether there were differences in outcomes when surgery was performed in the night (10 pm-6 am), on weekends (Saturday or Sunday), or during summer months (June-August).

Methods

We used United Network for Organ Sharing (UNOS) data sets of adults transplanted between February 27, 2002, and September 30, 2016. We estimated the start time of liver transplant surgery by utilizing the cross-clamp time and cold ischemia time (cross-clamp time + cold ischemia time - 2 h). The survival outcomes were estimated by Kaplan-Meier survival analysis. Patients with hepatocellular carcinoma (HCC) were analyzed separately. The independent effect of time of transplant on outcomes was analyzed after adjusting for common confounders, including Model for End-stage Liver Diseases scores and transplant center volume.

Results

During the study period, 4 434 (9.6%) were done in the night, 12 147 (26.4%) over weekends, and 11 976 (26%) during summer months. The graft and patient survival and complications were not influenced by the time of transplant for both HCC and non-HCC population. Cox regression analysis after adjusting for risk factors, including Model for End-stage Liver Diseases, donor risk index, and liver center volume, confirmed that there were no significant differences in outcomes.

Conclusions

Our study showed that the time of transplant surgery whether done during nights, weekends, or summer months had no effect on graft or patient survival irrespective of center volume, patient, or donor risk factors.

Is liver transplantation 'out-of-hours' non-inferior to 'in-hours' transplantation? A retrospective analysis of the UK Transplant Registry

OBJECTIVES

Increased morbidity and mortality have been associated with weekend and night-time clinical activity. We sought to compare the outcomes of liver transplantation (LT) between weekdays and weekends or night-time and day-time to determine if 'out-of-hours' LT has acceptable results compared with 'in-hours'.

DESIGN, SETTING AND PARTICIPANTS

We conducted a retrospective analysis of patient outcomes for all 8816 adult, liver-only transplants (2000-2014) from the UK Transplant Registry.

OUTCOME MEASURES

Outcome measures were graft failure (loss of the graft with or without death) and transplant failure (either graft failure or death with a functioning graft) at 30 days, 1 year and 3 years post-transplantation. The association of these outcomes with weekend versus weekday and day versus night transplantation were explored, following the construction of a risk-adjusted Cox regression model.

RESULTS

Similar patient and donor characteristics were observed between weekend and weekday transplantation. Unadjusted graft failure estimates were 5.7% at 30 days, 10.4% at 1 year and 14.6% at 3 years; transplant failure estimates were 7.9%, 15.3% and 21.3% respectively.A risk-adjusted Cox regression model demonstrated a significantly lower adjusted HR (95% CI) of transplant failure for weekend transplant of 0.77 (0.66 to 0.91) within 30 days, 0.86 (0.77 to 0.97) within 1 year, 0.89 (0.81 to 0.99) within 3 years and for graft failure of 0.81 (0.67 to 0.97) within 30 days. For patients without transplant failure within 30 days, there was no weekend effect on transplant failure. Neither night-time procurement nor transplantation were associated with an increased hazard of transplant or graft failure.

CONCLUSIONS

Weekend and night-time LT outcomes were non-inferior to weekday or day-time transplantation, and we observed a possible small beneficial effect of weekend transplantation. The structure of LT services in the UK delivers acceptable outcomes 'out-of-hours' and may offer wider lessons for weekend working structures.

Kidney Discard Rates in the United States During American Transplant Congress Meetings

Supplemental digital content is available in the text.

Background

Deceased-donor kidney discard rates vary by region, but it is unknown whether discard rates and transplant outcomes vary during the American Transplant Congress (ATC) each year.

Methods

Using national registry data, we determined rates of kidney discard, delayed graft function, graft failure, and mortality from December 31, 1999, through December 30, 2015, during ATC dates and compared these rates with those on the same days of the week during the 2 weeks before and after the ATC (non-ATC). We used multivariable regression to determine associations between ATC and these outcomes.

Results

From 7902 donors (1575 ATC; 6327 non-ATC), 12 588 recipients received kidney transplants (2455 ATC; 10 133 non-ATC), and 2666 kidneys were discarded (582 ATC; 2084 non-ATC). Kidneys were more often discarded during ATC (19% vs 17%, P = 0.006; adjusted odds ratio, 1.21; 95% confidence interval, 1.05-1.40). There were no significant differences in donor, transplant, or recipient characteristics by ATC/non-ATC dates or by ATC/non-ATC transplant dates for delayed graft function, graft failure, or mortality.

Conclusions

On the basis of a 21% increased odds of discard, the ATC itself may result in 5 additional kidney discards during this important conference every year, which suggests the need for innovative staffing or other logistic solutions during these planned meetings.

Weekend Effect in Carotid Endarterectomy

Background and Purpose- Patients undergoing surgery on the weekend may experience worse outcomes, but this weekend effect has not been studied in carotid endarterectomy (CEA). Methods- We identified patients undergoing isolated CEA in the Vascular Quality Initiative between 2003 and 2018. Our primary outcome was in-hospital stroke or perioperative death (stroke/death), stratified by symptom status. For asymptomatic patients, we also compared rates of the Centers for Medicare and Medicaid Services quality metric prolonged length of stay (>2 days or failed discharge home). We calculated propensity scores and used multilevel, inverse probability weighted logistic regression clustering at the hospital level. Results- There were 86 123 repairs during the study period, 53% asymptomatic lesions and 47% symptomatic. Only 0.7% of asymptomatic patients underwent CEA on the weekend, compared with 3.1% of symptomatic patients. Patients undergoing weekend repairs were more often white, with lower rates of most comorbidities. In asymptomatic patients, weekend operations were associated significantly higher odds of stroke/death (odds ratio [OR], 2.3 [1.1-4.8]; P=0.02), and prolonged length of stay (OR, 3.6 [2.7-4.7]; P<0.001). In symptomatic patients, weekend operations were associated with significantly higher adjusted odds of stroke/death (OR, 1.7 [1.2-2.4]; P=0.007) and longer postoperative length of stay (3.3 days versus 2.0 days, P=0.002). However, the difference in stroke/death was driven by patients presenting with stroke (OR, 2.2 [1.5-2.3]; P<0.001), rather than those presenting with transient ischemic attack (OR, 1.2 [0.6-2.1]; P=0.56). Conclusions- We found evidence of a significant weekend effect in CEA, as weekend operations in asymptomatic patients and patients who presented with stroke were associated with higher rates of stroke/death and prolonged length of stay. However, there was no evidence of such an effect in patients with transient ischemic attack. These data suggest that weekend CEA should be avoided except in the case of expedited revascularization after transient ischemic attack.

Weekend effect on early allograft outcome after kidney transplantation- a multi-centre cohort study

Weekend surgery may be associated with a higher risk of early complications, but the effect of the timing of kidney transplant surgery on early allograft outcome remains uncertain. The aim of this study is to evaluate whether the association between weekend transplant surgery and allograft failure was modified by prevalent vascular disease. Using data from the Australia and New Zealand Dialysis and Transplant registry, we examined the association between weekend status and 90-day and 1-year allograft failure in deceased donor transplant recipients between 1994-2012. Two-way interaction between vascular disease and weekend status was examined. Of 6622 recipients, 1868 (28.2%) received transplants during weekends. Compared with weekday transplants, weekend transplants were associated with an adjusted hazard ratio (HR) for 90-day and 1-year allograft failure of 0.99 (0.78-1.25; P = 0.917) and 0.93 (0.76-1.13, P = 0.468), respectively. There was a significant interaction between prevalent vascular disease and weekend status for 90-day allograft failure (P_interaction = 0.008) but not at 1-year, such that patients with vascular disease were more likely to experience 90-day allograft failure if transplanted on weekend (versus weekdays), particularly failures secondary to vascular complications. Timing of transplantation does not impact on allograft outcome, although those with vascular disease may benefit from more intensive post-transplant follow-up for potential vascular complications.

The weekend effect in liver transplantation

Background

The weekend effect describes a phenomenon whereby patients admitted to hospitals on weekends are at higher risk of complications compared to those admitted during weekdays. However, if a weekend effect exists in orthotopic liver transplantation (oLT).

Methods

We analyzed oLT between 2006 and 2016 and stratified patients into weekday (Monday to Friday) and weekend (Saturday, Sunday) groups. Primary outcome measures were one-year patient and graft survival.

Results

364 deceased donor livers were transplanted into 329 patients with 246 weekday (74.77%) and 83 weekend (25.23%) patients. Potential confounders (e.g. age, ischemia time, MELD score) were comparable. One-year patient and graft survival were similar. Frequencies of rejections, primary-non function or re-transplantation were not different. The day of transplantation was not associated with one-year patient and graft survival in multivariate analysis.

Conclusions

We provide the first data for the Eurotransplant region on oLT stratified for weekend and weekday procedures and our findings suggest there was no weekend effect on oLT. While we hypothesize that the absent weekend effect is due to standardized transplant procedures and specialized multidisciplinary transplant teams, our results are encouraging showing oLT is a safe and successful procedure, independent from the day of the week.

Outcome of transplantation performed outside the regular working hours: A systematic review and meta-analysis of the literature

Transplant procedures are frequently performed outside the regular working hours (after hours). In general surgery, several studies observed worse outcomes for operations performed after hours. The predetermined hypothesis was that patients undergoing transplantation during after hours might suffer from an excess in post-operative mortality and morbidity when compared to patients undergoing transplantations during the regular working hours. A systematic review of the PubMed database identified 11,993 records, of which eleven cohort studies including a total of 287,741 patients investigated the association between the starting time of transplant surgery and postoperative mortality (primary outcome) and/or morbidity (secondary outcome). Eight studies evaluated kidney transplants (in 165,277 patients), two studies analyzed liver transplants (in 95,346 patients), and one study investigated transplantations of thoracic organs (in 27,118 patients). Results were conflicting with two studies (in liver and lung transplantation) showing an increased mortality for transplantations performed after hours, and five studies showing no effects on mortality. A meta-analysis on estimates from four studies yielded a hazard ratio of 1.01 (95% CI, 0.98 to 1.04) for mortality comparing transplantations performed during versus outside the regular working hours. The evidence was also inconclusive for a variety of morbidity outcomes with studies demonstrating either a deterioration of outcome, no effect or an improved outcome for after hours procedures. On the basis of the available evidence, it appears impossible to give an unequivocal recommendation regarding starting times in transplant surgery.

Is there a "weekend effect" in kidney transplantation?

The ‘weekend effect’ describes increased adverse outcomes after weekend hospitalization.

We examined weekend-weekday differences in the outcome of 580 patients following renal transplantation (RTx, brain dead donors) between January 2007 and December 2014 at our center. 3-year patient and graft survival, incidence of delayed graft function (DGF), acute rejections and estimated glomerular filtration rate (eGFR, CKD-EPI) at 1 year as well as surgical complications were assessed. Of all 580 transplants, 416 (71.7%) were performed on weekdays (Monday-Friday) and 164 (28.3%) on weekends (Saturday-Sunday). 3-year patient and graft survival, frequencies of DGF, acute rejections and 1-year eGFR as well as length of hospital stay were similar between RTx patients transplanted on weekdays or weekends, respectively. However, a noticeable difference was detected with regard to surgical complications which were more frequent in RTx patients transplanted on weekends. All results remained consistent across all definitions of weekend status. Our results suggest that weekend transplant status does not affect functional short-term and long-term outcomes after RTx. The standardized protocols and operationalized processes applied in RTx might contribute to this finding and may provide a model for other medical procedures that are performed on weekends to improve efficiency and outcomes. The higher rate of surgical complications after weekend RTx needs further elaboration to fully assess the presence of a weekend effect in RTx.

The weekend effect: transplantation is not "immune"

The "weekend effect" has been widely studied in various health care settings, but it has received less attention in the field of transplantation. The study by Mohan et al. reveals that this phenomenon exists in discard rates for deceased donor kidneys in the United States. These findings emphasize the importance of reducing unexplained variations in kidney discard rates, especially in light of the ongoing shortage of transplantable organs.

Outcomes After Weekend Admission for Deceased Donor Kidney Transplantation: A Population Cohort Study

BACKGROUND

Outcomes for weekend hospital admissions or emergency procedures have become a topical and controversial issue for the UK National Health Service. Deceased-donor kidney transplantation is frequently performed at weekends and evidence for its relative safety are lacking.

METHODS

We undertook a population-based cohort analysis, obtaining data from every deceased-donor kidney-alone transplant procedure performed in England between January 2003 and December 2014. Data were extracted from Hospital Episode Statistics, with linkage to the Office for National Statistics to create a comprehensive dataset for mortality, rehospitalization and kidney allograft failure/rejection for weekend (defined as Friday to Sunday) versus weekday transplantation.

RESULTS

Data were extracted for 12 902 deceased-donor kidney alone transplants performed in all 19 English transplant centres between 2003 and 2014. Based on initial χ tests, no significant difference was observed when comparing weekend versus weekday transplantation in 30-day (0.9% vs 1.2%; P = 0.126) or 1-year mortality (3.7% vs 3.8%; P = 0.788), 1-year kidney allograft failure/rejection (16.7% vs 16.8%; P = 0.897), delayed graft function (29.97% vs 29.36%; P = 0.457) or 1-year risk for readmission (63.5% vs 63.3%; P = 0.774). In a Cox regression model, transplantation at the weekend was not associated with any increased risk for 1-year mortality, rehospitalization, or allograft failure/rejection.

CONCLUSIONS

Deceased-donor kidney transplants performed at the weekend do not have inferior short-term outcomes on the basis of 1-year risk for rehospitalization, mortality, or allograft failure/rejection. Our data are reassuring for patients and professionals alike, but may also provide speculative insight into models of care that attenuate the weekend effect.

Weekday and Survival After Cardiac Surgery-A Swedish Nationwide Cohort Study in 106 473 Patients

BACKGROUND

The purpose of this study was to investigate the association between weekday of surgery and survival following cardiac surgery.

METHODS AND RESULTS

In a nationwide cohort study, we included all patients who underwent cardiac surgery in 1999-2013 from the SWEDEHEART (Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies) register. All-cause mortality until March 2014 was obtained from national registers. The association between weekday of surgery and mortality was estimated using Cox regression, and reported as hazard ratios with 95% CI. We used the restricted mean survival time difference to estimate loss of life related to weekday of surgery. Among 106 473 patients, 25 221 (24%), 24 471 (23%), 22 977 (22%), 20 189 (19%), 9251 (8.7%), and 4364 (4.1%) underwent surgery during a Monday, Tuesday, Wednesday, Thursday, Friday, and a Saturday/Sunday, respectively. More patients were operated on urgently during Friday to Sunday, and unadjusted analyses showed higher early and late mortality in those patients. The adjusted hazard ratios (95% CI) were 1.00 (0.89-1.13), 1.00 (0.88-1.12), 1.02 (0.90-1.16), 1.17 (1.01-1.37), and 1.05 (0.86-1.29) in patients who underwent surgery during a Tuesday, Wednesday, Thursday, Friday, and Saturday/Sunday compared to a Monday, after 1 year of follow-up conditional on 30-day survival. In elective surgery (n=46 146), the 1-year restricted mean survival time difference (95% CI) was -0.5 (-1.8-0.8), -0.5 (-1.9-0.8), -1.0 (-2.6-0.5), 0.02 (-2.2-2.3), and -1.2 (-6.3-3.9) days in patients who underwent surgery during a Tuesday, Wednesday, Thursday, Friday, and a Saturday/Sunday, respectively, compared to a Monday.

CONCLUSIONS

We found no evidence of a clinically relevant weekday effect in patents who underwent cardiac surgery in Sweden during a 15-year period. These data suggest that the early risk and long-term prognosis following cardiac surgery was not affected by the weekday of surgery.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02276950.