Same-day discharge (SDD) vs standard enhanced recovery after surgery (ERAS) protocols for major colorectal surgery: a systematic review

Background Enhanced recovery after surgery (ERAS) programs are well-established, resulting in improved outcomes and shorter length of hospital stay (LOS). Same-day discharge (SDD), or “hyper-ERAS”, is a natural progression of ERAS. This systematic review aims to compare the safety and efficacy of SDD against conventional ERAS in colorectal surgery. Methods The protocol was prospectively registered in PROSPERO (394793). A systematic search was performed in major databases to identify relevant articles, and a narrative systematic review was performed. Primary outcomes were readmission rates and length of hospital stay (LOS). Secondary outcomes were operative time and blood loss, postoperative pain, morbidity, nausea or vomiting, and patient satisfaction. Risks of bias was assessed using the ROBINS-I tool. Results Thirteen studies were included, with five single-arm and eight comparative studies, of which one was a randomised controlled trial. This comprised a total of 38,854 patients (SDD: 1622; ERAS: 37,232). Of the 1622 patients on the SDD pathway, 1590 patients (98%) were successfully discharged within 24 h of surgery. While most studies had an overall low risk of bias, there was considerable variability in inclusion criteria, types of surgery or anaesthesia, and discharge criteria. SDD resulted in a significantly reduced postoperative LOS, without increasing risk of 30-day readmission. Intraoperative blood loss and postoperative morbidity rates were comparable between both groups. Operative duration was shorter in the SDD group. Patient-reported satisfaction was high in the SDD cohort. Conclusion SDD protocols appear to be safe and feasible in selected patients undergoing major colorectal operations. Randomised controlled trials are necessary to further substantiate these findings. Supplementary Information The online version contains supplementary material available at 10.1007/s00384-023-04408-7.


Introduction
Enhanced recovery after surgery (ERAS) protocols are a set of evidence-based practices spanning the perioperative period, designed to optimise postoperative outcomes by minimising the physiological stress response and maintaining or rapidly restoring baseline function [1].The concept that a structured, multimodal, multidisciplinary pathway can result in accelerated recovery after surgery first emerged in the early 2000s amongst patients undergoing colorectal surgery [2][3][4].ERAS programmes are now well-established in colorectal surgery, with the benefits over traditional care demonstrated by several meta-analyses of randomised controlled trials [5][6][7][8].
In 2018, the international ERAS Society published their fourth set of consensus guidelines concerning perioperative care in elective colorectal surgery [9].In December 2022, the American Society of Colon and Rectal Surgeons (ASCRS) and the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) have also collaborated to report updated clinical practice guidelines [10], which aim to lead international efforts in defining the optimal perioperative approach to colorectal surgery based upon the principles of ERAS.
Continued interest and innovation in the various aspects of ERAS have led to its application, in whole or in part, 110 Page 2 of 22 amongst unconventional patient cohorts.Thus far, the feasibility of ERAS pathways has been demonstrated for emergency/non-elective resections [11,12], elderly patients [13,14], low rectal cancer [15], inflammatory bowel disease [16], as well as cytoreductive surgery with hyperthermic intraperitoneal chemotherapy [17].Regardless of patient profile, ERAS protocol compliance has been well documented as the most essential factor contributing to better postoperative outcomes [18][19][20].Moreover, addressing clinicians' resistance to change and rectifying long-standing but non-evidence-based practices are important to ensure successful implementation of ERAS programmes [20].
One of the most striking consequences of improved patient recovery with ERAS is a substantially reduced length of hospital stay (LOS).Various meta-analyses have consistently demonstrated that ERAS decreases the postoperative LOS by an average of two days, as compared to standard perioperative care [5,6,21].There is increasing recognition that same-day discharge (SDD), defined as hospital discharge within 24 h of surgery, or "hyper-ERAS", may be feasible for a select group of physiologically fit patients.
Given the growing adoption of SDD as a natural progression of ERAS with an increasing amount of contemporaneous evidence, a systematic review is timely to determine the overall feasibility of "hyper-ERAS" for colorectal surgery and discuss the applications of individual components of SDD.

Search process
This study protocol was prospectively registered in PROS-PERO (394793).This study was performed according to the Cochrane Handbook of Systematic Reviews and Metaanalysis version 6.2 (2021), and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) statement guidelines [36].In consult with our institution's librarian, we derived an exhaustive permutation of the following Medical Subject Headings (MeSH) (expanded) terms: "colon surgery", "colorectal surgery", "rectal surgery", "colectomy", "colon resection", "ERAS", "enhanced recovery" "23 h", "same day discharge".Using this search strategy, an electronic search was performed on 25 December 2022 in the following databases: Medline (via PubMed), EMBASE, Cochrane databases, and the ClinicalTrials.govwebsite, to identify all published and indexed studies investigating same-day discharge protocols after colorectal surgery.A manual search of the reference lists of relevant studies was conducted to identify additional studies for potential inclusion.In addition, a search of grey literature (conference proceedings, theses, published abstracts) was performed, as per recommendation in the AMSTAR 2 checklist [37].

Inclusion and exclusion criteria
Both randomised and non-randomised controlled trials were included if outcomes were reported for patients undergoing same-day/23-h discharge protocols after colorectal resection surgeries.Given the relative lack of comparative studies, single-arm studies with reported outcomes and extractable data were included.Non-English studies as well as English studies with no extractable data were excluded as there were no available translators at our institution.

Selection of studies
As seen in the PRISMA diagram (Fig. 1), the selection of studies was conducted in two distinct stages.Firstly, two reviewers (VZ, IW) independently screened the studies for preliminary inclusion by their titles and abstracts, and the full text of these studies would then be re-assessed for final inclusion.The senior author would be the arbiter to resolve differences of opinions regarding the studies' eligibility by consensus.

Outcomes of interest and data extraction
Outcomes of interest included intraoperative and postoperative variables which were extracted independently by two authors using a standardised proforma.Primary outcomes were readmission rates and length of hospital stay.Secondary outcomes were operative time, intraoperative blood loss, conversion to open surgery, postoperative morbidity, pain, nausea and vomiting, patient satisfaction, and protocol compliance.In addition to the outcomes above, we extracted the following data from each study: first author, year, type of publication, age, gender, perioperative protocols, type of surgeries, stage of tumour (when applicable), American Society of Anaesthesiologists (ASA) scores, comorbidities.Data extraction was performed in an independent fashion by VZ and IW, and conflicts were resolved either by consensus or with discussion with the senior author.

Statistical analysis
Where possible, statistical analyses were performed using the RevMan 5.4 software (The Nordic Cochrane Centre, Copenhagen, Denmark), where pooling of risk ratio (RR) was performed for dichotomous variables; and weighted mean difference (WMD) or standardised mean difference (SMD) conducted as the summary statistic for continuous variables.Statistical heterogeneity was assessed using the I 2 statistic.A random-effects model was chosen when the I 2 statistic was greater than 50%, and a fixed-effects model otherwise.Results were reported with 95 percent confidence intervals (95% CI), and a P value of less than 0.05 was treated as statistically significant.
Pair-wise meta-analyses were not performed given small number of comparative studies, as well as the significant heterogeneity in study protocols and reporting of results.Subgroup analyses were also not performed given the lack of data stratification.Thus, a narrative systematic review was undertaken.

Assessment of bias
The Risk of Bias in Non-randomised Studies -of Interventions (ROBINS-I) tool [39] was utilised to assess the quality and risks of bias from confounding, selection of participants, classification of interventions, deviations from intended intervention, missing data, measurement of outcomes, and selection of reported results.Publication bias was not assessed using the funnel plot and Egger's regression test since there were less than 10 studies.

Systematic search
Out of a total of 1,185 papers, 29 were included after title and abstract review.These 29 papers were reviewed in entirety and 13 were included in the final systematic review, of which five were single-arm and eight were comparative studies (one randomised controlled trial).The systematic search process and reasons for exclusion are stated in Fig. 1.
The 13 studies comprised a total of 38,854 patients, of whom 1622 received the SDD protocol and 37,232 received conventional ERAS protocol.Of the 1622 patients receiving SDD protocol, 1590 patients (98%) were successfully discharged within 24 h.Gignoux et al. (2015) contributed the least number of patients to the SDD pool (0.3%), while McKenna et al. contributed the most (55.9%).Across the studies, the mean age ranged from 57.4 to 67.0 years in the SDD arm, and 56.5 to 72.6 years in the conventional ERAS arm.The proportion of males ranged from 35 to 80% in the SDD arm, and 40.3% to 62.5% in the conventional ERAS arm.
All procedures were minimally invasive surgeries (MIS), done via laparoscopic or robotic methods.Surgeries performed included colectomies, anterior resections, stoma closures, Hartmann's reversals and parastomal hernia repairs.The indications for surgery included both benign and malignant conditions.All except one single-arm study [34] reported the indications for surgery.The proportion of patients with malignant indications ranged from 20 to 100% in the SDD arm, and 42% to 100% in the conventional ERAS arm.Patients in most studies were discharged home.Four studies [25,29,31,33] only included patients in the SDD arm if they stayed close to the hospital (less than 30 min drive away).Detailed baseline study characteristics are shown in Table 1.The ERAS and follow-up protocols are reported in Table 2.

Patient selection for SDD and criteria for early discharge
Bednarski et al. [23] randomised patients to the SDD arm.Brandt et al. [24] allowed patient opt-in for SDD.Most prospective studies [22, 25-27, 29, 31-33, 35] selected patients for SDD based on clinical and social characteristics.Dobradin et al. [28] and McKenna et al. [30] reported retrospective studies without elaboration of SDD selection criteria.For most studies, the final decision for early discharge was made by the surgeon, without a standard discharge checklist.However, McKenna et al. [30], and both studies by Gignoux et al. [22,35] only discharged patients early if they met an objective set of discharge criteria.

Study quality
Most studies had an overall low risk of bias based on the ROBINS-I tool (Supplementary Fig. 1) and were deemed to be methodologically robust.Three studies, by de Azevedo et al. [27], Popeskou et al. [31], and Tweed et al. [32], had moderate risks of bias, mainly due to missing data and selection of participants.

Primary outcomes
All outcomes are summarised in Table 3.
SDD protocols did not lead to increased 30-day readmission rates compared to standard ERAS.Six studies, by Bednarski et al. [23], Brandt et al. [24], Lee et al. [29], Popeskou et al. [31], Tweed et al. [32], and Levy et al. [33], reported no significant differences in 30-day readmission rates between both groups.The remaining two studies did not publish readmission rate data for the control group but reported a 30-day readmission rate of 6.8% and 0% in the SDD group [27,33].

Operative time
Two studies reported significantly quicker operative times with SDD.Brandt et al. reported a 35 min reduction in median operative time in the SDD arm compared to standard ERAS (120 min vs 155 min, P = 0.002), for mostly sigmoid resections and right hemicolectomies [24].Lee et al. demonstrated a 61 min reduction in mean operative time with SDD versus conventional ERAS (116 min vs 177 min, P < 0.001) [29].Levy et al. also demonstrated quicker median operative times in the SDD group compared to control (73 min vs 88 min, P = 0.17) [33], although this was not statistically significant.Mckenna et al. showed that median LOS significantly increased as the operative duration increased [30].Patients discharged POD 0 to 1 had a median operative time of 95 min (IQR 66-141 min), while patients discharged on POD 2 and 3 had significantly longer median operative times of 143 min (IQR 106-185 min) and 159 min (IQR 119-209 min) respectively (P < 0.0001) [30].This reflects the longer recovery period required for more complex surgery.Patient randomisation after surgery.
Discharged to own home or hotel lodging in the immediate surrounding area.
Patients were required to reside within close travelling distance (2-3 h) of the hospital.

Brandt et al. (2013) [24]
Pre-operative: -Pre-operative bowel preparation with a rectal enema on the night and morning prior to surgery (only for sigmoidectomy patients) -On day of surgery, all patients received 200 ml Provide Xtra Intra-operative: -Induction of GA with propofol and fentanyl -Urinary catheters and oral tubes were only used during surgery.No drains were used Post-operative: -Postoperative pain control: oral Paracetamol, Ibuprofen, Morphine (if needed) -All patients mobilised on day of surgery and given general diet Planned clinic review after POD 10.
Postoperative patient opt-in process for early discharge.
Discharged to own home.
de  -Use of spinal analgesia using a local anaesthetic (2.5 ml heavy bupivacaine 0.5%) and 0.25 mg diamorphine rather than epidural analgesia.
-Despite targeting intravascular volume using oesophageal Doppler during surgery, three of the ten patients required further colloid boluses to restore or normalize oxygen delivery on the evening of surgery.
On the evening of discharge, the research registrar called the patient to ensure that there were no problems.
Patients were given a contact number that they could call if there was a problem.Clinic review POD 3.   -Surgical site infection bundle use, multimodal opioid sparing pain control, pre-op antiemetics guided by screening, multimodal nausea prophylaxis, tailor crystalloids to avoid excess, goal directed fluid therapy, avoidance of drains and tubes (unchanged from ERAS) -Minimally invasive approach and minimally invasive extraction (advanced from ERAS) 1.The use of minimally invasive surgery was employed in all procedures, with a majority performed robotically.Not described in ERAS, a minimally invasive manipulation approach was employed as well.It avoids regular tissue grabbing, and instead applies positional changes and sweeping methods for exposure and manipulation Preoperative: -Patient counselling: perioperative care, surgery, and LOS -Bowel preparation: 1 gallon of polyethylene glycol electrolyte solution 1 day before operation -IV antibiotics: 1 h before operation Intra-operative: -Laparoscopic surgery -No use of abdominal drains, nasogastric tubes, prokinetic agents, opioid antagonists -No use of epidural anaesthesia Postoperative: -Immediate postoperative liquid diet -Early ambulation initiated within 24 h -Prompt removal of bladder catheter -Pain management: 10 mg of Ketorolac by mouth -Follow-up at 1 week advised -Laxatives, opioid antagonists, and prokinetic agents were not used Clinic review 1 week after discharge or earlier if necessary.
Retrospective study without elaboration on selection criteria.

Gignoux et al. (2015) [22]
Pre-operative: -Cancer immunonutrition was prescribed for 7 days -No bowel preparation -Fasting except for oral intake of 400 mL of sweetened clear liquids two hours before surgery -Pre-operative analgesia of Paracetamol Intra-operative: -  Pre-operative: -Immunonutrition (Oral Impact, 200 mL 3times per day for 7 days) was prescribed to patients with cancer -No mechanical bowel preparation -All eligible patients were asked to perform ''modern fasting'' which is a normal meal the previous evening, followed by oral intake of a 400 mL carbohydrate-loaded drink2 hours before surgery -Prophylactic antibiotics were administered intravenously at the induction of anaesthesia Intra-operative: -Infiltration of local anaesthetic (ropivacaine 7.5 mg, 30 mL) at the incisions site or transverse abdominal plane block -No preoperative sedative medication, hyperoxygenation (if O2at 80%), anaesthetic agents with a short duration of action, and limited intravenous fluid intake during surgery (lower total target of 5 mL/kg/h amounting to less than1000 mL) -Vessel sealing was performed using 38hermos-fusion scissors.
-No gastric tube, urinary catheter, or abdominal drains were inserted.
-Skin closure was performed with absorbable sutures and strips.
-Hypothermia was actively prevented by using warming blankets, a warming mattress, and an intravenous fluid warmer.Post-operative: -Intraoperative and postoperative analgesia aimed to minimise narcotic use by using a multimodal combination of Paracetamol, Nefopam, Lidocaine, Ketamine, Tramadol, and Morphine -Prevention of postoperative nausea and vomiting consisted of intra-operative intravenous administration of Droperidol and/or Dexamethasone.
-Chewing gum was suggested to the patient once awake and cooperative.
-On return to the ambulatory surgical unit, patients received no intravenous perfusion; only oral analgesia was administered.
-Within the following 2 h, patients were encouraged to walk and food was allowed.

Conversion
None of the studies reported conversions from minimally invasive to open surgery.

Postoperative morbidity
Six [23,24,29,30,32,33] of the eight comparative studies reported complication rates following both SDD and standard ERAS, while the remaining two [27,31] did not report complication rates at all.All six studies found similar morbidity rates between the SDD and standard ERAS.Notably, McKenna et al. reported significantly lower superficial infection rates (1.8% vs 2.3%, P < 0.01) in the SDD cohort as compared to those discharged from postoperative day 2 to 5 [30].Deep surgical site infection rates (0.1% vs 0.3%, P = 0.05) and anastomotic leak rates (0.6% vs 1.2%, P = 0.05) were also lower in the SDD group, although these differences did not reach statistical significance [30].All five single-arm studies evaluated postoperative morbidity [22,25,26,28,35].Campbell et al. reported one patient with nausea and vomiting and one with high ileostomy output [25].Curfman et al. reported 30-day emergency department visits, including two patients with abdominal pain, and one with urinary retention, one with leg pain and another with diarrhoea [26].Gignoux's 2015 study reported one patient with dysuria and one with an incisional hematoma [22].The prospective study by Gignoux et al. in 2019 reported an overall 30-day morbidity rate of 24.8% with SDD, of which 72% were Clavien-Dindo grade I [35].Dobradin et al. reported zero complications with SDD [28].
Four [22,25,26,28] of the five single-arm studies reported no high-grade complications requiring reoperation.Gignoux's 2019 study, comprising 157 patients, reported two patients with rectal bleeding, three with wound abscesses, one with colitis, three with anastomotic leak, two with small bowel intestinal obstruction, and one patient with omental necrosis [35].

Postoperative pain
One comparative study measured postoperative pain using the Brief Pain Inventory (BPI) score [23], with a higher mean discharge pain score in the SDD compared to the control  [35].

Patient satisfaction
Five studies evaluated patient satisfaction [22,29,32,33,35].Of these, only one study compared patient satisfaction between SDD and standard ERAS and found no significant differences between the treatment arms for any of the questionnaire items [22].Nearly all respondents felt that they did not have to be kept in the hospital for a longer period to recover from surgery.In the other four studies, patient satisfaction was only assessed in the SDD arm [22,29,32,33].All four studies reported that most respondents were highly satisfied with the SDD protocol.Levy et al. [33] and Gignoux et al. [35] reported that most SDD patients would recommend this programme to others.

Protocol compliance
Popeskou et al. reported a 100% adherence rate to the ERAS protocol [31].No other studies evaluated patient or clinician compliance to individual components of the ERAS or SDD protocols.

Discussion
This is the first systematic review investigating the safety and efficacy of same-day discharge (SDD) protocols, or "hyper-ERAS", after colorectal surgery, showing a significant reduction in LOS, low risks of readmissions, and comparable risks of morbidity.The benefits of a reduced LOS are numerous and include a reduction in nosocomial infections [36], thromboembolic events [37], healthcare costs [38], and improvement in morbidity and mortality rates while enhancing quality of life and patient satisfaction [37].
The safety and acceptability of SDD protocols depends on a multitude of factors, including patient factors (physiological fitness or presence of comorbidities, disease status, compliance to the pathway), surgical factors (type or complexity of surgery, anaesthetic protocols), and the extent of postoperative assessment or care (teleconsultations, home visitations, etc.).Each of these are key tenets of the reviewed studies and should be considered prior to initial implementation of SDD programmes.

Patient factors
Patients selected to undergo SDD were invariably fitter individuals without serious health problems or poorly controlled chronic medical conditions, which would otherwise have heightened perioperative risks.The high rate of successful SDD amongst patients selected for SDD programmes amongst the reviewed studies reflects the appropriateness of patient selection.Cognitive impairment, high ASA scores, or the presence of significant comorbidities were frequently used exclusion criteria for SDD.Others excluded patients with a history of major or complex abdominal surgeries, or those with prior severe postoperative nausea or vomiting.Patients with poor health literacy, without suitable caregivers, should also be excluded from SDD.
For a more objective evaluation for fitness for discharge, several studies [22,30,35] used the Chung criteria [39], consisting of five variables including vital signs (temperature, pulse, respiration), ambulatory status, nausea and vomiting, pain, and surgical bleeding.A cut-off score of less than 9 out of 10 was used for patient exclusion from SDD. Gignoux et al. employed a 2-stage discharge process [22,35].First, the Modified Aldrete score [40] was used to discharge patients from the post-anaesthesia care unit.This score consists of aspects of motor activity, breathing, blood pressure, level of consciousness and oxygen saturation.Patients with a score above 9 were transferred from PACU to the ambulatory surgical unit.Patients were subsequently discharged from hospital in the evening if they met the Chung discharge criteria.

Surgical and anaesthetic factors
Patients scheduled for more complex surgeries e.g., multivisceral resections, low rectal resections, resections requiring bowel diversion with ostomy, etc., should not be considered for SDD.Moreover, prolonged surgery, major intraoperative complications or unanticipated difficulties can compromise postoperative recovery and warrant exclusion from SDD protocols at the discretion of the operating surgeon or anaesthetist.Laparoscopy and other minimally invasive surgery (MIS) options reduce operative trauma to the abdominal wall, reducing postoperative pain, analgesia use [41], improving LOS, as well as decreasing rates of readmission and reoperation [42].It is unsurprising that MIS techniques have become the cornerstone of colorectal ERAS and SDD protocols.All patients who underwent SDD in this review had MIS colorectal surgery.Several operative variations can further improve patient recovery by minimising operative trauma and pain, including intracorporeal versus extracorporeal anastomosis for laparoscopic right hemicolectomy [43].Pfannenstiel specimen extraction versus midline specimen extraction [44], or natural orifice specimen extraction versus conventional transabdominal specimen extraction [45,46].Individual surgeon expertise and experience are important factors [47,48], as well as proficiency with the surgical platforms used, including conventional laparoscopy, robotic surgery, or transanal approaches.
The type of anaesthesia and postoperative analgesia administered also influences recovery.Opioid-sparing modalities can reduce postoperative ileus, nausea and urinary retention [9,10], all of which can prolong LOS.Transversus abdominis plane (TAP) block has been shown to provide effective pain relief resulting in a significant reduction in opioid use following colorectal surgery [49,50].This method was employed by five of the reviewed studies [25-27, 29, 35].In a recently reported randomised controlled trial, bilateral erector spinae plane (ESP) block was also demonstrated to reduce pain scores and opioid requirements for 24 h following laparoscopic colorectal surgery [51].While this method was not employed by any of the reviewed SDD studies, it may be a viable alternative to TAP block for SDD pathways.
The 2022 American ERAS guidelines for colorectal surgery strongly recommend pre-emptive, multimodal antiemetic prophylaxis to reduce PONV [10].Apart from utilisation of opioid-sparing analgesia and reducing operative time, decreasing inhalational anaesthesia can also reduce the risk of PONV [10].Propofol-based total intravenous anaesthesia (TIVA) has been shown to lower the risk of PONV, reducing post-extubation pain scores and time spent in the post-anaesthesia care unit, while improving patient satisfaction scores, compared to inhalational anaesthesia [52].Four of the reviewed studies reported PONV amongst SDD patients [25,32,33,35].Two studies reported administration of intraoperative droperidol and dexamethasone to reduce the risk of PONV [22,35].Tweed et al. initially administered a combination of spinal anaesthesia with bupivacaine-glucose and morphine intrathecally prior to general anaesthesia [32].However, after the first nine patients, this was switched to 60-80 mg intrathecal prilocaine in combination with TIVA, because of an observed increase in incidence of PONV and urinary retention [32].

Postoperative home monitoring
Home assessment of patients for post-SDD is essential for recognition of serious morbidity which may require urgent interventions.Adequate counselling should be provided to patients or caregivers, particularly advice concerning the early symptoms of potential complications.Additionally, a convenient channel for communication and/or evaluation between patients, caregivers, and trained healthcare professionals during the early post-discharge period allows for reassurance for minor postoperative issues, including expected gastrointestinal symptoms, or outpatient treatment for minor complications instead of hospital readmission.The postoperative complication rate and distribution of Clavien-Dindo grade of severity were similar between SDD and standard ERAS arms in the comparative study by Tweed et al. [32].However, the readmission rate in the SDD group was more than threefold that of the control group (17.1% vs 5.3%, P = 0.051) [32], with outpatient treatment potentially possible in more than half of SDD readmissions.
Availability of and compliance to remote health assessments, as well as familiarity with digital platforms, are important aspects of SDD pathways.Five studies monitored patients via telephone calls with early clinic follow-up appointments [25-27, 32, 33].Bednarski et al. described a "telerecovery" method, where patients underwent videoconferencing with their physicians following discharge [23].The study protocol also allowed for outpatient intravenous fluid hydration at an ambulatory infusion centre when the patient was identified to have inadequate oral intake or assessed to be at high risk of dehydration [23].Lee et al. piloted a mobile application that enabled direct communication between patients and physicians, with the added function of daily patient-reported health questionnaire administration [29].
Assessment of individual comfort level with remote postoperative monitoring, in lieu of physical ward rounds, is required.This will likely vary across geographical locations and healthcare settings, and is further dependent on several factors including patient or caregiver techsavviness or proximity of their residence to the hospital.Appropriate preoperative counselling and reassurance will likely increase patient confidence with remote monitoring modalities.Two studies instituted early healthcare worker home visitation following discharge [22,35].Gignoux et.al.instituted a post-discharge protocol consisting of daily home visits by a nurse for the first 10 postoperative days [35].These resource-intensive initiatives may not be cost-effective in the long-term and modifications can be made once the feasibility of SDD pathways are demonstrated.

Limitations
The review is limited by the paucity of randomised trials comparing SDD with traditional ERAS.Moreover, there was marked heterogeneity in study designs, with significant variability in inclusion criteria, types of surgery, methods of anaesthesia, and discharge criteria, or other components of SDD protocols.The overall compliance rates to SDD or conventional ERAS protocols was also mostly unreported.In addition, not all studies reported the reasons for failure of SDD amongst patients included within SDD pathways.This may be relevant as discharge delays can often be due to social or non-medical reasons, clinician or patient preferences, as well as private insurance requirements [53].
The strict inclusion criteria for SDD limits its generalisability.Differences in patient demographic, surgical, or disease characteristics can result in confounding.SDD patients were significantly younger than their conventional ERAS counterparts in many studies [24,27,32,33].Most studies did not adjust for confounders during their analysis.Publication bias may ensue when studies with favourable outcomes are preferred over those with negative or inconclusive findings [54].Lastly, selective reporting of outcomes, including omitting unfavourable or statistically insignificant outcomes, or publishing only a subset of analysed data, can undermine the validity of results.

Conclusion
SDD protocols appear to be safe and feasible in a select group of patients undergoing major colorectal operations, resulting in reduced LOS with no increased risk of 30-day readmissions and postoperative morbidity compared to traditional ERAS.Randomised controlled trials are necessary to further substantiate these findings.

Fig. 1
Fig. 1 Prisma flow diagram for the systematic review showing database searches, number of abstracts screened, and full texts retrieved Preoperative selection based on clinical and social factors.SDD offered only if patient lived within proximity of the hospital (< 10 miles) 110 Page 10 of 22Table 2

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Dedicated preoperative counselling -Baseline assessment with physical examination, electrocardiogram on indication and standard laboratory work-up -Nutritional screening by dietician -Fasting 6 h prior to surgery for solid food and 2 h prior to surgery for liquids -Oral carbohydrate loading for non-diabetic patients at least 2 h prior to surgery -Bowel preparation with bisacodyl (2 tablets of 5 mg the night before surgery and 1 tablet the morning of surgery) for patients scheduled for left-sided colon surgery -Preoperative analgesia with 1000 mg Paracetamol and 600 mg Gabapentin (300 mg if glomerular filtration rate < 60 ml/min or age > 70 years) Intraoperative: -Spinal anaesthesia (Prilocaine)* prior to induction of general anaesthesia -Use of short-acting total intravenous anaesthesia (propofol, remifentanil and ketamine) -Restrictive fluid management with continuous perfusion of Ringer Lactate 3 ml/kg/h -Deep neuromuscular blockade (Rocuronium bromide perfusion) -Lung protective ventilation (Total Volume 6-8 ml/kg; minimum FiO2 and optimal PEEP) -Adequate temperature regulation with forced air warming and core temperature monitoring -Starting intra-abdominal pressure at 12 mmHg with a gradual decrease to 8 mmHg -Minimally invasive surgery with intracorporal anastomosis -Extraction of specimen through a suprapubic Pfannenstiel incision, no additional mini-laparotomy performed Post-operative -directly: -Postoperative pain management consisted of Paracetamol (4 × 1000 mg), Meloxicam (1 × 7.5 mg daily for 3 days).If indicated, 5-20 mg Oxynorm (per os) or opioids in the form of Piritramide (intravenously) were given -Intake and gastro-intestinal motility were stimulated by offering an ice lolly on the recovery ward -Mobilisation was actively stimulated -If an urinary catheter was placed; this was removed before 10:00 PM on the surgical ward POD 1: -Routine physical examination by the ward physician -Evaluation of recovery and readiness for discharge -Expectation management regarding postoperative recovery and provision of an information booklet about postoperative recovery *Initially, patients received a combination of spinal anaesthesia with bupivacaineglucose and morphine intrathecally prior to general anaesthesia.After the first 9 included patients, this was switched to intrathecal Prilocaine in combination with total intravenous anaesthesia (TIVA), because of an increase in the incidence of nausea and urinary retention postoperatively.The remaining included patients received spinal anaesthesia with 60-80 mg Prilocaine (weight based) Telephonic aftercare was conducted by the nurse on the evening of discharge and on POD 4 to evaluate recovery and assess the presence of abnormal vital signs.Clinic review one week after discharge Preoperative selection based on clinical and social factors.Discharged to own home Campbell et al. (2022) [25] -Pre-operative ERAS education class for all patients -Alvimopam pre-operatively -Multimodal pain control algorithm including preop acetaminophen, gabapentin, NSAIDs and low dose narcotics -Ultrasound guided transversus abdominis plane block performed by anaesthesia in PACU -Liquid diet in recovery unit -Recommended to have full liquid diet in POD1 and advance to regular diet as tolerated -All patients ambulate independently before discharge -DVT prophylaxis given pre-operatively and in recovery unit, followed by injections at home -Foley catheters were removed postoperatively, and if the patient was unable to void, were replaced and the patient was discharged with a leg bag -Additional ostomy teaching was performed, intravenous fluids given -Patients were advised to stay close to the hospital postoperatively Clinic review arranged within the first 4 postoperative days, and patients were contacted by telephone daily during that period.All patients had in-person 2-week clinic review.Preoperative selection based on clinical and social factors.Patients were advised to stay close to the hospital postoperatively Two of the seven patients chose to stay in a nearby hotel for 24 to 48 h as they lived more than 30 min away from the hospital

2 . 1 .
Minimally invasive extraction method.When possible, natural orifice extraction or extraction via ostomy take down sites was employed.Post-operative: -Early mobilisation, immediate resumption of diet, early discontinuation of IV fluid, multimodal opioid sparing pain control, multimodal antinausea regimen, no urinary catheter use (unchanged from ERAS) -Post-operative education, post-operative patient physician communication (advanced from ERAS) Patient preference of communication method (phone or Internet medical portal) is confirmed and recorded in the EMR at the preoperative visit.A provider routinely contacts the patient after discharge to assess their progress, address any questions, and analyse for any potential complications.Patients were called by the operative physician on POD 1, and by a colorectal specific physician's assistant on POD 3 to assess for any issues and answer questions.Clinic review between POD 5 and POD 7 and scheduled for further routine postoperative reviews from that point.Preoperative selection based on clinical and social factors.Discharged to own home Dobradin et al. (2013) [28] Laparoscopic technique -Hyperoxygenation with FiO2 80% -Anaesthesia agents with short duration of action -Limited IV fluid during surgery -Intra-op and post-op analgesia aimed to minimise narcotic use by employing multimodal combination of Paracetamol, Nefopam, Lidocaine, Ketamine, Magnesium Sulphate, Tramadol and Morphine -Prevention of post-operative nausea vomiting by intra-operative administration of droperidol and dexamethasone Daily home visits every afternoon by a nurse for the first 10 postoperative days with clinical monitoring Daily morning phone calls Pre-operative patient selection but discharge allowed based on Chung score [39] Discharge was authorized if the patient met the exit criteria according to the Chung score tube, urinary catheter, or drains -No IV perfusion -Only oral analgesia -Paracetamol, Tramadol and Nefopam (per patient request for first 24 h) -Encouraged to walk and food allowed in semi-solid form 2 h after return to ward -Prevention of ileus and associated post-operative nausea vomiting by chewing gum and oral magnesium supplements 3 × daily -Thromboembolic prophylaxis -daily injection of enoxaparin SC for 10 days Gignoux et al. (2019) [35]

Table 1
Baseline study characteristics of studies included in the systematic review of SDD vs standard ERAS following major colorectal surgery

Table 2
ERAS and follow-up protocols of studies included in the systematic review of SDD vs standard ERAS following major colorectal surgery

Table 3
Outcomes of interest of studies included in the systematic review of SDD vs standard ERAS following major colorectal surgery