Effectiveness Of Enhanced Recovery After Surgery (ERAS) Protocol In Reducing Length Of Hospital Stay And Complication Rate In Elderly Patients With Colorectal Surgery: A Review

Importance of length of hospital stay in judging the effectiveness of ERAS protocol

Discuss about the Beneficial Pathway in Colorectal Surgery.

Length of hospital stay (LoS) is one important clinical parameter to judge the effectiveness of ERAS because increased LoS is a major issue in elderly patients going for colorectal surgery (Shalaby et al. 2016). The clinical parameter of LoS was evaluated in all of the nine studies and the significance of LoS data is evaluated here. LoS was found to reduce in all the studies and the median range for total hospital stay days was between 5-7 days in patients between 65 to 80 years of age. For example,  Kisialeusk et al. (2015) showed mean hospital stay of 4.52 in group below 65 years and 5.48% in group above 65 years and showed median Los OF 6 days (Gonzalez-Ayora et al. 2016). The data presented by Gonzalez-Ayora et al. (2016) is significant as it also mentioned that many patients were discharged within the estimated day according to ERAS protocol. Despite this strength, methodological limitations were found in this study because of small sample size and lack of consideration for taking a control group. However, elements of ERAS are credible as it was a multi-center study evaluating process and outcome of various hospitals. This outcome is found consistent with many other studies too (Baek et al. 2013).

Majority of studies also depicted no significant difference in LoS between age groups. The uniqueness of the research by Khan and Pandey (2016) was that it took very elderly patient and non-very elderly patient and it gave a surprising result where LoS was low for very early patient compared to other group. However, the categorization of age group was a limitation in other studies. For instance, instead of taking standard group of below and above 65 years of age, Kisialeusk et al. (2015) took three participant group which decreased the credibility and transparency of the work. Sample recruitment related biases were also found in the study by P?dziwiatr et al. (2015) as it took patient below 55 years and patient above 88 years which failed to fulfill the criteria of research question. It did not presented an elderly population group. Hence, this weakness in study design also gives the implication that taking chronological age group is not an important criterion to judge the effectiveness of ERAS protocol. In addition, the outcome of LoS in all the nine studies clearly proved that LoS can be regarded as an ideal marker of ERAS performance.

Evaluation of length of hospital stay in elderly patients

Many important insights were also gained regarding ways to improve the LoS outcome in relation to ERAS protocol. For instance, the important clinical implication obtained from the article by Khan and Pandey (2016) was that to improve postoperative outcome in very elderly patient receiving ERAS protocol, there is a need to focus on complex post operative requirement for elderly patient. Gramlich et al. (2017) also supported the fact that process improvement is the key to fulfill major elements of ERAS protocol.

From the evaluation all the nine studies, it was also evident that early mobilization is an important for the success of ERAS protocol instead of age related protocol in patients with colorectal surgery. This was concluded in 4 studies (Kisialeusk et al. 2015; Forsmo et al. 2017; Slieker et al. 2017; Braga et al. 2017). However, the difference was that Kisialeusk et al. (2015); Forsmo et al. (2017) specifically targeted early mobilization as a critical factor for improvement in ERAS program outcome, whereas other two studies regarded early mobilization as important apart from other ERAS protocol elements. Fulfilling as many elements of ERAS protocol is associated with decrease in hospital stay. For instance, Braga et al. (2017) argued that early mobilization along with adequate pain control, early removal of bladder catheter and fluid restriction are effective strategy to minimize risk of complication in elderly patient. Slieker et al. (2017) also explained that when patient’s are able to achieve mobilization in early days and take adequate food, then other clinical outcome of patient eventually improves. This outcome is consistent with a study that evaluated impact of successful implementation of ERAS in patients after colorectal surgery. It showed that early mobilization and diet advancement are the foundation for ERAS. Nutritional advancement strategy has the advantage of reducing catabolism, post-operative insulin sensitivity, LoS and improving patient satisfaction with post operative care (Sarin et al. 2015). However, Mir et al. (2015) also mentioned anesthetic protocols and perioperative fluid management is also essential for the achieving optimal post-operative outcome in settings of ERAS.

The complication rate was assessed in all the nine studies and the median complication rate obtained in studies ranged between 35%- 40%. Majority of studies evaluated complication by means of Clavien-Dindo classification. Inconsistent outcome were found in terms of complication greater than Grade 3b. Kisialeusk et al. (2015) showed no complications above grade III, however in the study by Forsmo et al. (2017), 7% of the complications were greater than Grade 3b. In the study by Forsmo et al. (2017), consistent data could not be obtained as comparison of outcome was mainly done by comparing the data of elderly patient with young population group. No significance differences were found in both groups. There were 7% elderly patient with one or major complication and 12% cases of readmission within 30 days. In contrast, Kisialeusk et al. (2015) gave clear insight into post operative complication rate and the rate of overall complication rate was 35.8% including general and surgical complications. The overall conclusion from the review of complication rate in all the nine studies suggests that complication rate is drastically reduced. Even if complication occurred, the rate of minor complication was more compared to major complication (Gonzalez-Ayora et al. 2016). This is also consistent with other research outcome as showed that ERAS program implementation is associated with reduction in mortality rate (Ljungqvist and Hubner 2018).

Insight for improving post-operative outcomes with ERAS protocol

The evidence by Zeng (2017) is found to be most effective in terms of methodological rigour as it analyzed outcome by taking a control group receiving conventional treatment and an intervention group receiving ERAS. The intervention group has low overall complication rate of about 26.6% compared to the control group. This evidence convincing proved the efficacy of ERAS in reducing complication rate compared to conventional perioperative care. However, the limitation was not participants were not randomly assigned to different group and this contributed to selection bias. Selection biases reduce the reliability and credibility of research evidence. However, it was effective in proving that ERAS protocols like fluid restriction and prolonged starvation reduces incidence of complication particularly urinary tract infection. A meta-analysis of RCT studies also proved that overall morbidity rate is reduced in patient going for colorectal surgery by means of ERAS (Greco et al. 2014).

P?dziwiatr et al. (2015) also proved that ERAS is effective in proving that short term treatment outcomes in patient over 80 years and those below 5 years are similar. Although the study did not represented an elderly population cohort, however the study outcome is significant as 50-87 of patient above 75-85 years of age are operated for colorectal surgery. However, patient above the age of 85 years receive no treatment because of the perception that patient at this age may die because of complications related to bleeding. This study is found beneficial in changing this trend it showed that no difference in ERAS element is needed for both group of patient. This evidence provides effective evidence to show that ERAS protocol is safe for elderly patient with colorectal surgery and age does not affects patient’s ability for mobilization post colorectal surgery. P?dziwiatr et al. (2016) also proved that ageing is not a factor predicting successful outcome of ERAS. From the review of evidence, it is also learnt that evidence based post-operative care process, communication with team members and continuous audit are the three main pillars of ERAS.

The clinical outcome readmission was evaluated in eight studies, except the one by Zeng et al. (2017). Except two  studies (Khan and Pandey 2016; P?dziwiatr et al. 2015),  all the other research articles showed that the rate of readmission increased in patient above 65 years of age, however the gap was very small. The median range of readmissions to hospitals ranged between 4% to 12% in the nine studies. There were two studies which showed that the rate of rehospitalizatoon was lower in patient below 65 years compared to those above 65 years (Forsmo et al. 2017); Kisialeusk et al. 2015). There were six studies were readmission rate was below 10% (Kisialeusk et al. 2015; Gonzalez-Ayora et al. 2016; Khan and Pandey 2016; P?dziwiatr et al. 2015; Zeng 2017; Braga et al. 2017) and three studies were readmission rate was above 10% (Forsmo et al. 2017; Slieker et al. 2017; Baek et al. 2013). Most of the studies classified research participants into group above 65 years and below 65 years, two or three studies were done with very early group too. This outcome proves that ERAS is an effective protocol in reducing readmission rate in elderly patient with colorectal surgery.

Importance of early mobilization in ERAS protocol

To understand the effectiveness of ERAS in reducing the readmission rate, there is a need to critically analyze the study which gave minimum rate for readmission rate in elderly patient undergoing laparascopic surgery. Among all the nine studies, the study by P?dziwiatr et al. (2015) was found to be the most effective in achieving optimal readmission rate. The study achieved readmission rate of 2.9 % for group above 80 years and 2.4% for people above 55 years of age. P?dziwiatr et al. (2015) was able to achieve minimum difference between rehospitalization rate because of effective preparation for surgery. The ERAS protocol implemented before surgery and methodological rigor is the strength of the work. It proved that age is not a factor that hinders the effectiveness of ERAS process, instead quality of perioperative care determines the achievement of optimal surgical outcome for patient. It focused on desired level of physical activity and nutrition intervention for patient two weeks before surgery. Some limitations were also found in research studies because of selection biases. For instance, patient above 80 years were not analyzed in majority of studies and this was important to understand how ERAS protocol should differ in very elderly patient and elderly patients.  Assessment of frailty is critical to predicting morbidity in elderly patient going for colorectal surgery (Tan et al. 2012). Secondly, positive outcome for ERAS is also dependent on elderly people’s ability to comply with the protocol. This aspect is extremely important to reduce risk of complication, shorten LoS and reduce readmission rate (Ahmed et al. 2010).

These outcomes in research studies indicated that age is a proven risk factor for complication and high morbidity is found in elderly patients above 65 years of age with colorectal surgery. However this is a contradictory finding as Pirrera et al. (2017) proved in a retrospective cohort study done in patients with above 65 years of age that no significant difference in morbidity, readmission rate and mortality is found in patients above 65 years of age and age in a not a contraindication to the implementation of ERAS protocol. This was also found in the study by Khan and Pandey (2016) as the readmission rate was higher in younger group compared to very elderly group. This is an indication that ERAS protocol is effective in reducing readmission rate and facilitative recovery in elderly patient with colorectal surgery. A systematic review of ERAS after colorectal surgery in elderly patient also showed ERAS is effective in reducing complication and eventually decreasing the rate of readmission to hospitals (Bagnall et al. 2014). To improve the effectiveness of ERAS, future studies should consider about specialized post-operative requirement for very elderly people to get positive results for elderly patient with colorectal surgery. Future studies should also focus on recruiting a control group receiving traditional treatment as this would help to predict the difference in clinical outcome between ERAS group and control group.

Fulfillment of ERAS protocol elements associated with decreased length of hospital stay

In relation to the outcome variable for mortality, there were seven studies which gave data on mortality rate post implementation of ERAS protocol in patients undergoing colorectal surgery (Gonzalez-Ayora et al. 2016; Khan and Pandey 2016; Zeng 2017; Braga et al. 2017) (Forsmo et al. 2017; Slieker et al. 2017; Baek et al. 2013). Understanding trends related to mortality rate is important because evidence has showed that colorectal surgery is a procedure associated with increased risk of morbidity and mortality in patient compared to other surgical procedure (Yeung et al. 2017). In the selected nine research studies, the median range for mortality rate within 30 days was between (0-4) for different elderly age group. It also showed that mortality was not dependent on ageing variable as 2 cases of death was reported in patient between 66-79 years of age compared to patient above 80 years of age (Forsmo et al. 2017). Very less difference in mortality rate was also found in all the nine studies. Another clinically significant result was that mortality was found in patients who developed complications after suregy. However, this is a contradictory finding as review of research articles on relation between mortality and complication has revealed that patients without drains had higher mortality but lower complication rate. This gives the implication that intraperitoneal drain increase chances of complication and early removal of post-operative drainage should be targeted to reduce mortality rate (Abeles, Kwasnicki and Darzi 2017).

The outcome of no difference in 30-day mortality rate is a reliable outcome as several other studies reported similar outcome after colorectal surgery in elderly patient (Baek et al. 2013; Keller et al. 2013; Naef et al. 2010). However, in case of selected nine papers, Forsmo et al. 2017 work was found to have weakness in sample characteristics and the process of characterizing age group. Although great difference is found related to comorbidity in patients at different stage of ageing, however this is affected by choice of surgical intervention instead of chronological age of patients (Scott et al. 2015). Zeng (2017) argued that pneumoperitoneum also increase risk of complication in laparascopic surgery compared to younger patient. This indicates that laparascopic surgery in combination with ERAS is necessary to improve post-operative outcome in elderly patient.  Khan and Pandey (2016) also showed no difference in mortality rate between different age group, however the limitation found in terms of research method was that it included participants above 75 years, it did not matched the WHO criteria set for very elderly group. Hence, application of the findings specifically for very elderly cohort is very low.

Evaluation of complication rate in elderly patients undergoing ERAS protocol

In the study by Slieker et al. (2017) where age group of less and more than 70 years was taken, the mortality rate was found to be 2 for less than 70 years and 6 for more than 70 years. However, after analyzing the causes of deaths in the selected participant group, it was found that cardiac complication, renal failure and septic shocks were the cause of deaths. This depicts the weakness of recruitment strategy taken by researcher. The cause of death indicates that there might be patients with a history of renal failure or other cardiovascular complication, however researcher include all patient above 18 years of age within the ERAS pathway without excluding any patient. This is ad drawback that resulted in outcome biases specifically for mortality rate.

Baek et al. (2013) was the only studies which reported no mortality rate in either group. Such outcome was possible because it used ‘fast-track’ program after laparascopic surgery to understand the safety of the procedure in older patient group compared to older patient group. ‘Fast-track’ is a synonym for ERAS and the main aspect of the program was postoperative patient education, post operative diet intake and mobilization, post operative analgesia and minimal starvation in the perioperative stage. There was lack of studies depicting the safety of the fast track program and by providing evidence regarding the safety of the fast track program, the evidence gave the direction to successfully apply fast track program for older patients.  On the whole, the review of all the nine evidence convincingly proves that death rate is significantly reduced for patient after implementation of ERAS. This is also consistent with other research studies (Spanjersberg et al. 2015).

Adherence is one critical factor that determines the effectiveness of other clinical outcomes while implementing ERAS for elderly patient. However, the review of the nine articles revealed that that this factor was not considered in most of the studies. Out of nine studies, only four studies evaluated the adherence or compliance to ERAS among research participants (Forsmo et al. 2017; P?dziwiatr et al. 2015; Slieker et al. 2017; Braga et al. 2017). From this evaluation, it was found that the adherence to ERAS pathway ranged between 55-86%. Another significant outcome was that adherence rate was almost equal in young and elderly patient with colorectal surgery. For instance, Forsmo et al. (2017) showed no difference in adherence rate between young and elderly patient and P?dziwiatr et al. (2015) reported highest adherence rate of about 85.2% in very elderly patient. Braga et al. (2017) was the only study which showed minimum adherence rate from the range of 55-70%. This was explained in terms of adherence rate for low operative physical status in different group.

Methodological strength of studies evaluating ERAS protocol

Forsmo et al. (2017) took chronological age wise group for comparison of research data by categorizing participants into ≤65 years group, 66-79 years group and ≥80 years. It considered adherence to ERAS protocol on the day of surgery, before surgery and until discharge. There adherence to protocol has very minimal difference in all the groups. This outcome might have emerged by consideration of strict inclusion criteria. This outcome also indicates that adherence to ERAS can be good for elderly population too compared to younger thus indicating that ERAS protocol are simple to be executed and followed by people above 65 years of age. Adherence to protocol is directly related to positive post operative outcomes like lesser complication rate and postoperative admissions in patient. This finding is consistent with the research study Partelli et al. (2016) which also proved that there is no difference in adherence between young and elderly patients.

Among all the four studies, one study that is of special significance is the research study by Slieker et al. (2017) where the main objective was comparison of adherence to ERAS pathway in colorectal patient below and above 70 years of age. This is the most effective evidence as it gives rich data on impact of adherence rate on functional recovery, hospital stay and post-operative complications. Methodological rigour was also seen in the study as the researcher took special criteria to measure adherence rate. For instance, the ERAS rate was calculated by the number of ERAS elements fulfilled. The study showed very small difference in adherence rate as younger patient had 78% adherence rate whereas older patient has 74% adherence rate. This study also proved that old age is a not a predictor of adherence rate, instead duration of surgery and type of surgery affected the adherence rate. This evidence is also consistent with the study by Li et al. (2017) which showed that high compliance with ERAS protocol reduces risk of complication, hospital stays and hospital cost too. It also showed that compliance rate differ based on factors like perioperative food management, early mobilization, removal of drainage tube and other factors. No link between ageing as a predictor of adherence rate was found (Gustafsson et al. 2011).

In terms of strength and weakness of the research design, it can be said that the study adapting randomized controlled trial method was most credible as it used strict inclusion criteria and block randomization approach (Forsmo et al. 2017). Some studies were not transferable as it was done only in single center and the routine of preoperative care may differ in different setting (P?dziwiatr et al. 2015). Although the research by Slieker et al. (2017) gave clinically significant outcome, however in this case data were collected prospectively which might be contributing to biases. It failed to recruit ideal elderly population cohort as the inclusion criteria was colorectal surgery patient above 70 years of age. However, this aspect can be ignored as identification of high risk patient for physiological fitness before surgery is more important than chronological age of patients (Wilson et al. 2015).

Safe application of ERAS protocol in elderly patients

Hence, from the review of nine articles on ERAS adherence, it can be concluded that ERAS protocol are feasible to be implemented in elderly patient undergoing colorectal surgery. Hence, instead of being concerned about adherence as a barrier to ERAS implemented for elderly patient, there is a need to review practice related barrier to make the process more efficacious and safe for patient. For instance, communication process between staffs can be improved as evidence has found lack of communication among staffs to be affecting outcome of the ERAS program (Lyon, Solomon and Harrison, 2014).

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Effectiveness of ERAS protocol in reducing readmission rate in elderly patients

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