Enhanced Recovery after Surgery (ERAS) in Emergency and Trauma Surgery

Abstract

Enhanced Recovery After Surgery (ERAS) protocols reduce the length of hospital stay (LHS), complications, and costs for many elective surgical procedures. The ERAS protocol concerns a multimodal, multidisciplinary, standardized, evidence-based approach to minimize stress for patients undergoing surgery. A similar, structured approach appears to improve outcomes, including mortality, for patients undergoing high-risk emergency general surgery, and emergency laparotomy, in particular. Recently, several studies have been published, including new guidelines, analyzing the benefits of ERAS protocols in emergency surgery and trauma patients. The aim of this chapter is to analyze the available data and the benefits of using ERAS protocols in patients undergoing emergency and trauma surgery.

1. Introduction

Originating from the pioneering work of Professor Henrik Kehlet in the 1990s at the University of Copenhagen, Denmark, the Enhanced Recovery After Surgery (ERAS) protocol concerns a multimodal, multidisciplinary, standardized, evidence-based approach to minimize stress for patients undergoing surgery, promoting healthy organ function, and ultimately improving outcomes [1]. The first guidelines, developed by the ERAS Study Group, founded in 2001 by Professor Ken Fearon of the University of Edinburgh, UK, and Professor Olle Ljungqvist of the Karolinska Institutet, Sweden, focused on patients undergoing colorectal surgery [2]. Subsequently, in 2009, guidelines for implementation of enhanced recovery protocols (ERPs) were published by the Association of Surgeons of Great Britain and Ireland (ASGBI) [3]. These guidelines, which involve surgeons, anesthetists, nurses, and allied health professionals, address pre-admission, pre-operative, intra-operative, and post-operative items. It was demonstrated that adherence to each component of the ERAS protocol can significantly reduce length of hospital stay (LHS), infection risks, complications such as anastomotic leak, and overall morbidity and mortality rates [4, 5, 6].

2. Principles of ERAS protocol

Pre-operative optimization for elective surgery requires treating modifiable medical conditions like diabetes, hypertension, renal disease, atrial fibrillation, chronic obstructive pulmonary disease (COPD), and asthma to achieve optimal patient performance status and minimize related complications. Also, as pre-operative anemia is linked to in-hospital mortality, 30-day mortality, stroke, acute kidney injury, and sepsis [7], oral or intravenous iron therapy or erythropoietin therapy should be assessed to reach a target of hemoglobin (Hb) >12–13 g/dL.

Nutritional assessments are crucial for identifying malnutrition, hyponutrition, and sarcopenia, given their predictive value for mortality, LHS, infections, and anastomotic leaks [8, 9, 10]. Appropriate interventions, including oral diets, weight loss, or nutritional support, can reduce complications by approximately 25% [11]. Prehabilitation along with smoking and alcohol cessation was proven to significantly improve patient outcomes [12, 13, 14, 15].

Many ERAS items have challenged traditional surgical dogma through an in-depth understanding of the pathophysiological response to surgical stress. For instance, the practice of pre-operative fasting was reevaluated following observations of worsened outcomes in animal models and evidence supporting rapid gastric emptying after fluid intake [16].

Studies comparing patients undergoing intravenous glucose infusion with or without insulin treatment to fasted patients demonstrated improved insulin sensitivity, reduced post-operative protein loss, and lower cortisol level increases after surgery [17, 18]. Following these findings, the ERAS group developed a low-osmolarity carbohydrate-rich drink (maltodextrin) to improve gastric emptying and stimulate the insulin response [19].

Pre-operative bowel preparation before colorectal surgery was questioned due to the potential risks of hypovolemia and electrolyte imbalance, which can worsen cardiac or renal comorbidities. Studies indicated that bowel preparation may exacerbate post-operative ileus and affect anastomotic healing. As a result, bowel preparation was discouraged and rectal enemas are suggested as the preferred approach for left colon and rectal surgery [20].

Careful attention by the anesthesiologist is required during intra-operative management, particularly with regard to antimicrobial prophylaxis, prevention of hypothermia, monitoring of the depth of anesthesia and neuromuscular blockade, intravenous fluid management, and analgesia.

Hypothermia was proven to increase blood loss (16%) requiring blood transfusion (22%), increased stress response with excessive catecholamine release causing vasoconstriction, increased afterload, myocardial ischemia, cardiac arrhythmias, surgical site infection, and coagulopathy [21].

Intra-operative fluid management should aim to optimize cardiac function, intravascular volume, and tissue perfusion with an appropriate near-zero balance line [22]. Excessive fluid administration may result in pulmonary and anastomotic edema. Conversely, inadequate fluid intake can reduce cardiac output. Poor fluid management is also associated with increased inflammatory and metabolic markers such as interleukin 6 (IL-6) and reactive oxygen species (ROS) during a major surgery [23]. Goal-directed fluid therapy is recommended by ERAS guidelines.

Monitoring the depth of anesthesia and maintaining neuromuscular blockade enable the effective management of general anesthetic drugs and the prevention of cognitive dysfunction and post-operative delirium [24].

Multimodal analgesia, tailored to the surgical approach, is essential. Whenever possible, offering minimally invasive surgery (MIS) along with multimodal analgesia is recommended. Inadequate analgesic programs can exacerbate surgical stress, leading to poor mobilization, prolonged bed rest, respiratory issues, and delayed gastrointestinal function return, thereby prolonging hospital stay [21]. A balance of good anesthesia, stress response modification, and satisfactory side effect profile should be achieved [21].

Epidural anesthesia should be avoided due to their potential to alter endocrine and metabolic responses to surgical stress. Patient-controlled analgesia (PCA) has been associated with high pain scores in the early post-operative period, indicating inadequate pain control. Opioid-sparing analgesia should be assessed to avoid post-operative nausea and vomiting and delayed gastrointestinal function return. Minimal opioid use in the shortest period, combined with anti-inflammatory steroidal and non-steroidal drugs, plays a key role in managing surgical stress and inflammation. Initially, spinal analgesia was considered preferable to epidurals and PCA because it allowed for opioid-sparing therapies. However, the introduction of abdominal wall blocks demonstrated similar outcomes in MIS while avoiding the side effect of hypotension and offering the added benefits of rapid awakening and early mobilization [25].

The ERAS program does not promote a particular minimally invasive technique, but instead advocates for avoiding open surgery as it has been shown to be an independent factor in improving outcomes, reducing LHS, avoiding wound complications such as surgical site infections and incisional hernias, and minimizing stress responses [4, 26]. Table 1 illustrates the impact of fast-track care versus standard care on the length of hospital stay in colonic surgery [27]:

LHS in colonic surgery	Fast-track care	Standard of care
Laparoscopic surgery	5 (4–7) days	6 (4–8.5) days
Open surgery	6 (4.5–10) days	7 (6–10.5) days

Table 1.

Results from Enroll (enhanced recovery open versus laparoscopic): A multicenter randomized trial of conventional versus laparoscopic surgery for colorectal cancer within an enhanced recovery program [27].

Two other frequently debated items concern the use of drains and the nasogastric tube. In ERAS, the routine use of drainage should be avoided as they can act as a foreign body, potentially providing a pathway for contamination, and are often rapidly obstructed and therefore ineffective. Drains should be reserved for selected high-risk patients and removed early [28].

The use of nasogastric tube has been challenged as well, as it is ineffective for its purpose of decreasing gastric distension after surgery and avoiding respiratory complications such as pneumonia and pulmonary aspiration. Multiple systematic reviews of randomized trials have shown that patients who do not undergo routine nasogastric tube decompression or receive “early tube removal” experience a faster return of bowel function and reduced pulmonary complications compared to those who kept it in place until intestinal function had returned. Furthermore, some studies demonstrated an opposite effect on intestinal function return of gastric tube and pharyngeal and respiratory adverse events [29]. In upper gastrointestinal surgery, no difference in anastomotic leakage and mortality has been demonstrated in routine nasogastric decompression versus early removal, or in nasogastric tube reinsertion [30, 31].

The most innovative features of the ERAS protocol can be found in the post-operative management.

Early oral feeding has been shown to be safe: no increase in relevant complications was observed, and yet a decrease in mortality was observed when started within 24 h of surgery [32]. Functional recovery, major complications, and LHS were reduced in patients who were able to tolerate normal food from the first day even after gastrointestinal surgery [33]. Enteral nutrition supplementation in selected cases is necessary. Controversial results have been seen with immunonutrition: some trials showed a significant reduction in infectious complications [34, 35]. As oral intake starts quickly, intravenous fluid therapies should be taken into account only as supplement when oral intake is not sufficient, in order to avoid edema [33].

Early removal of the urinary catheter is another important challenge of the ERAS protocol, which promotes early mobilization and contributes to the prevention of post-operative ileus, which is another important goal [5].

Post-operative ileus is the consequence of a disturbance of neuronal and hormonal balance which creates a disorganized electrical activity and paralysis of the bowel [36]. Reducing edema, controlling electrolytes and the inflammatory response, sparing opioids, using minimally invasive surgery (MIS), avoiding the nasogastric tube, and implementing early feeding and mobilization can prevent post-operative ileus [37]. Prokinetics and laxatives can be used to treat it.

Antimicrobial prophylaxis should be given once before surgery. If contamination happens during surgery, it may be necessary to extend prophylaxis up to 24 h. Empirical treatment should be considered if the surgical site is contaminated and administered for a maximum of 3–5 days or as per the specific case. Long-term use of antibiotics is related to severe infections caused by antibiotic-resistant bacteria, which can lead to a higher mortality rate [38].

Prophylaxis for thromboembolism should be assessed based on risk factors and should be balanced against risk of bleeding. Pharmacological and non-pharmacological treatments should be used based on the risk assessment and for no longer than 14 days in ERAS protocol. Oral anticoagulant should be reintroduced as soon as the risk of bleeding is negligible (Table 2) [5].

Enhanced Recovery After Surgery (ERAS) items in colorectal surgery (2018)

Pre-admission information, education, counseling Pre-operative optimization Prehabilitation Pre-operative nutritional care Management of anemia Prevention of nausea and vomiting (PONV) Pre-anesthetic medication Antimicrobial prophylaxis and skin preparation Bowel preparation Pre-operative fluid and electrolyte therapy Pre-operative fasting and carbohydrate loading Standard anesthetic protocol Intra-operative fluid and electrolyte therapy Preventing intra-operative hypothermia Surgical access (open vs. minimal invasive surgery) Drainage of peritoneal cavity and pelvis Nasogastric intubation Multimodal post-operative analgesia Thromboprophylaxis Post-operative fluid and electrolyte therapy Urinary catheter Prevention of post-operative ileus Post-operative glycemic control Post-operative nutritional care Early mobilization

Table 2.

Guidelines for perioperative Care in Elective Colorectal Surgery: Enhanced recovery after surgery (ERAS) society recommendations [5].

Based on this evidence, many studies conducted worldwide demonstrated the feasibility of ERAS protocols and significant reduction in complications and post-operative mortality in these patients [39, 40, 41].

The ERAS protocol has faced criticism regarding readmission issues due to early discharge. However, the ERAS pathway does not compromise the standard of care’s fundamental principle of “safety first” but rather adds an efficiency perspective, challenging dogmatic questions and focusing on prehabilitation. Data have shown a decreased LHS without impact on readmission and emergency room utilization [42].

As the results became clearer, each side of surgery started to tailor its own protocol, adapting items for each situation. There are very few studies on trauma because of the disruptive nature of the emergency environment.

3. Enhanced recovery protocols in emergency surgery

The convincing results obtained in colorectal surgery led to investigating this kind of protocol in emergency surgery as well.

Among the earliest studies, convincing evidence of the effectiveness of ERPs in emergency surgery was provided by three landmark studies.

Møller et al.’s study evaluated the effect of a multimodal, multidisciplinary perioperative care program on mortality in patients with perforated peptic ulcers across seven Danish hospitals. The implementation of this program resulted in a remarkable reduction of 37% in the 30-day mortality rate compared to historical and concurrent national controls. This translates to saving one life for every 10 patients treated [43].

In the NELA (National Emergency Laparotomy Audit) study, the introduction of an emergency laparotomy pathway quality improvement care (ELPQuIC) bundle across four UK hospitals significantly reduced the risk of death following emergency laparotomy [44]. The ELPQuIC bundle encompassed a comprehensive set of evidence-based interventions, including early warning scores, early antibiotics, prompt surgery, goal-directed hemodynamic therapy, and post-operative intensive care. Because of implementation of this care bundle, the number of lives saved per 100 patients treated increased from 6.47 to 12.44. Remarkably, this improvement in mortality was observed without any significant difference in patient severity as assessed by the Portsmouth-Physiological and Operative Severity Score for the Enumeration of Mortality and Morbidity (P-POSSUM).

A subsequent study further examined the economic implications of implementing the ELPQuIC bundle, considering both hospital and societal perspectives. The analysis, conducted in accordance with the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) guidelines, revealed that while in-hospital costs were slightly higher, societal costs were reduced overall. This highlights the potential for cost savings to healthcare systems through the adoption of this care bundle [45].

The first evaluation of the ERAS pathway in emergency surgery focused on obstructive colorectal cancer treated in an emergency setting [46]. Lohsiriwat et al. published in 2014 the first retrospective comparison between standard of care and ERAS pathway for these patients, demonstrating its safety and beneficial effects. There were no differences in mortality or readmission between the groups, but the ERAS group started oral nutrition earlier, with an earlier return of bowel function and a shorter LHS, which meant an earlier start to adjuvant chemotherapy.

The first randomized study on applying ERAS program components after emergency surgery was published in 2014 by Gonenc et al. from Turkey for peptic ulcer perforation [47]. This landmark study demonstrated the feasibility and safety of implementing ERAS principles in the emergency setting. The study compared the outcomes of patients undergoing emergency laparotomy for peptic ulcer perforation who received either a standard care protocol or an ERAS-modified protocol and found that patients who received the ERAS-modified protocol had significantly shorter LHS, quicker return to oral intake, and lower rates of post-operative complications compared to those who received standard care. These findings highlighted the potential of ERAS to improve patient outcomes even in the context of emergency surgery.

Quiney et al. in 2016 identified key areas for improvement in the ERAS pathway for emergency settings [48]. They observed that delays in diagnosis could lead to delays and inadequate resuscitation, sepsis assessment, and post-operative care when intensive care unit (ICU) stay is needed. To address these issues, they proposed a stepwise approach that focuses on accelerating diagnosis in cases of ambiguous symptoms, early administration of broad-spectrum antibiotics after sepsis assessment, and predicting ICU stay.

Wisely et al. highlighted a changing mindset in their Australian group in the post-ERAS era (2016) [49]. They observed how ERAS principles had influenced their management in emergency surgery as a natural evolution of their pre-ERAS conventional care. For example, intravenous fluid infusion decreased sensitively after ERAS guidelines’ publication for elective surgery (p < 0.001), urinary catheter was considered unnecessary for more than 2 days and removed earlier in post-ERAS (p < 0.001), earlier removal of PCA has been seen (p = 0.001) and reduced drain placement (p = 0.001). No differences were seen between the two periods for anastomosis or stoma, oral intake, nasogastric tube use or earlier removal. Less major complications were observed in the post-ERAS group (p = 0.002) and when present they were related, on a multivariate analysis, to an important ERAS statement, which is an unfulfilled fluid balance within the first 48 h. At the end of their description, the group was enthusiastic about promoting other challenging principles of the ERAS protocols in emergency surgery.

Randomized trial with the aim of applying more ERAS items on emergency surgery was published with convincing results [50]. As experiences grew, other pathologies than intestinal obstruction and peptic ulcer perforation were treated with ERAS program highlighting the differences with elective surgery and the limited compliance, for example, in case of intra-abdominal infections [51].

The Spanish study by Viñas et al. showed the safety and benefit of ERAS-adapted program in left colectomy after colonic perforation. The new management showed significantly lower morbidity rates, with no additional mortality or readmissions. The ERAS group also showed a significantly shorter LHS. Their conclusion was that the ERAS guidelines should implement the emergency setting [52].

The key difference between emergency and elective surgery patients is that the former presents in a compromised state, often in high-risk patients with systemic inflammatory response syndrome (SIRS), sepsis or shock. The outcomes in emergency surgery are poor, with higher risk of death up to one-tenth at 30 days after surgery, one-fourth for patient over the age of 80 years, and higher risk of complications [53].

The above fact has been underlined by the encouraging results of several recent narrative reviews, systematic reviews, and meta-analyses on this topic [54, 55, 56, 57, 58, 59, 60].

4. ERAS principles in emergency surgery

Enhanced Recovery After Surgery (ERAS) Society finally published its own guidelines for perioperative care for emergency laparotomy in 2021 and 2023, including all the abdominal non-elective procedures, potentially life-threatening, excluding trauma laparotomies, vascular procedures, appendectomy, and cholecystectomy [61].

Pre-operative management is very different from elective surgery, and the main aim is to promptly correct any alteration in the patient’s homeostasis during investigations and diagnosis. Resuscitation and Early Warning Score (EWS) should guide a stepwise system of care: circulatory and respiratory stabilization, early goal-directed fluid therapy, and minimization of surgical delay have been shown by many studies to reduce mortality and LHS after surgery in this setting [62, 63, 64].

The pathophysiological derangement, such as SIRS or sepsis, gut dysfunction, insulin resistance, fluid shifts, and many others, depending on patient’s comorbidities and performance status, may last longer than its presentation. This may be considered for the treatment and the goal result [61]. Risk assessment using validated scores should guide pathways of care, whether non-operative management or operative one [65, 66].

Patient with multiple-organ failure (MOF) presentation, requiring damage-control surgery with open abdomen or ICU post-operative stay longer than 72 h, should not be candidate to ERAS protocol [61].

In these cases, the speed and efficiency of the process should be increased: in the first hour, blood cultures should be obtained, antibiotics should be promptly assessed, resuscitation with crystalloid should be evaluated and monitored by blood lactate, and potential vasopressors started [67].

Rapid diagnosis and treatment planning should be made: every delay is a cost to the patient survival, complications, and prolonged LHS. Computed tomography (CT) scan with intravenous contrast medium is the gold standard for abdominal diagnosis and should be acquired and discussed between surgeon and radiologist as soon as possible, whenever the patient is stable. In case of sepsis, the source control should be achieved surgically or through interventional radiology within 3 h from admission if shock is present, 6 h if not [61]. A Danish study proved that delayed emergency surgery in perforated peptic ulcer leads to reduced survival for every hour of delay from hospital admission [68], while a British study based on National Emergency Laparotomy Audit (NELA) data showed an increased mortality for delay beyond 72 h [69].

Pre-operative multidisciplinary counseling to the patient and the patient’s family with detailed information about the procedure, potential complication with stepwise strategies and post-operative pathway should be assessed, and most importantly, shared decision-making plays a crucial role in an emergency setting for a potentially fatal event [70].

The evaluation of frailty and cognitive assessment must be undertaken in elderly patients to optimize post-operative care, avoiding perioperative neurocognitive disorders and delirium triggered by medications [61]. The use of benzodiazepines should be avoided in elderly patients for the potential trigger to delirium and opioids should be minimized to avoid oversedation and hypoventilation [71].

In a patient who takes antithrombotic medications, reversal agents can be used prior emergency surgery to reduce the risk of hemorrhage. Vitamin K, fresh frozen plasma, prothrombin complex concentrate (PCC), recombinant coagulation factor, and monoclonal antibodies (idarucizumab) should be used if any major surgery is to be performed. Consider platelet transfusion in patients on antiplatelet therapy, after evaluation by a cardiologist, if there’s is a history of a recent coronary stent or procedure [72].

Fluid management should be goal directed, avoiding patient overload even in case of severe hypotension where inotropes can help to sustain circulation [61]. Electrolyte disorders (hypokalemia, hypomagnesemia, and hypophosphatemia) are frequent, potentially a trigger for atrial fibrillation, and should be corrected before or during surgery.

Hyperglycemia is also very common for the high levels of cortisol release, particularly in diabetic patients, but it leads to an overproduction of inflammatory mediators, ROS and free fatty acids (FFAs), which are potentially harmful to the endothelial vascular compartment and the immune system and can cause cellular damage [73].

There is no need to prepare the patient with carbohydrate load as in elective surgery, instead correction with insulin or glucose to reach levels of 144–180 mg/dL can reduce complications and mortality.

The use of nasogastric tubes in an emergency setting has a different rationale than elective surgery and has a different risk-benefit ratio. Aspiration of gastric distention for high gastric fluids may be beneficial. Post-operative management may be different than elective setting as well [61].

From an anesthesiologist’s point of view, emergency surgery patient is more demanding, frequently needs rapid sequence induction and intubation [74] for the higher risk of airway contamination, using fast curare and eventually cricoid compression, monitoring the depth of anesthesia with particular attention to the use of propofol in emergencies due to its hypotensive effects associated with increased use of vasopressors [75]. Ventilation as well should be carefully supervised because of the association between high peak pressure and development of post-operative pulmonary complication [76]. ERAS guidelines on emergency surgery suggest to start with a tidal volume of 6–8 ml/kg and a positive end expiratory pressure (PEEP) of 5 cmH₂O and thereafter to tailor it to patient needs [77].

Indication for neuromuscular block monitoring, PONV reduction, and temperature maintenance are similar to elective ERAS principles.

Multimodal opioid-sparing analgesia may be different and limited in an emergency setting: epidural catheter placement may not be safe in the presence of sepsis and coagulopathic modification, non-steroidal anti-inflammatory drugs (NSAIDs) should be cautiously used because of the high risk of acute kidney injury (AKI) in multiple-organ failure (MOF) patients, paracetamol as well in case of liver failure. Neuraxial blocks should be avoided in hemodynamically unstable patients to avoid sympathetic blockade, vasodilatation, and hypotension [75]. The use of local anesthetics on surgical wound, transversus abdominis plane (TAP) blockade, and intraperitoneal infiltration with local anesthetic could be effective in reducing post-operative pain within the first 6 h and opioid use in the first 24 h [78, 79, 80, 81].

Intra-operative choices should be based on the risk/benefit assessment considering not only patient’s conditions and pathology but also surgeon’s preference, skill, and experience.

Initial diagnostic laparoscopy is recommended because of the benefits already outlined, with an eventual conversion to open laparotomy [75]. If a gastrointestinal or colorectal anastomosis is required, the risk of leakage must be assessed [82, 83]. Even if the emergency setting represents a major risk it should not be considered as a contraindicationper se, as in many cases a primary anastomosis can be performed safely and should be carefully considered alongside any other alternative strategy [75]. Resection and stoma creation should be assessed in a shocked patient requiring vasopressor support.

In a critically ill patient, damage control for hemorrhage or source of infection control achieved as soon as possible delaying definitive anastomosis and abdominal wall closure for a planned re-laparotomy [84] was challenged in ERAS protocol. Whenever possible, definitive primary anastomosis and abdominal wall closure were demonstrated to lead to fewer overall operations, shorter ICU stay, and total hospital stay [85]. The use of negative pressure wound therapy (NPWT) for abdominal wall closure may be used for intra-abdominal sepsis, to reduce complications, reinterventions, and infections. Deferred wall closure may benefit from dynamic mesh traction on fascia besides vacuum-assisted closure therapy (VAC therapy) [86].

Traditionally, emergency laparotomy claimed routinary drainage, but many studies demonstrated no benefit over such routinary drainage. The World Society of Emergency Surgery (WSES) discouraged the use of drain in perforated appendicitis with or without abscess or peritonitis because there were no benefits about intra-abdominal abscess formation or surgical site infections [87]. Drain-related morbidities were described after perforated peptic ulcer as well (fever, peritoneal fluid collection, surgical site infection, and wound dehiscence) [88].

Antibiotic prophylaxis with a broad-spectrum agent should be administered and continued according to diagnosis, intra-operative findings, and field contamination [89]. Skin antisepsis is recommended. Use of a wound protector, new instruments, and glove change for closure was shown to bring about effective reduction of superficial and deep surgical site of infection [90].

At the end of an emergency procedure, the impact of surgery on metabolic and hemodynamic stability for extubation may be considered. Because of the high risk of re-intubation related to an ASA III patient (i.e., a patient with severe systemic disease as per the American Society of Anethesiologists’ (ASA) Physical Status Classification System) and abdominal surgery, frequently occurring in an emergency setting, extubation may not be indicated [91, 92]. A careful assessment of the patient’s condition should be scored in order to decide whether to extubate or transfer with intubated patient to the ICU, and patient post-operative destination [75].

In order to prevent post-operative pulmonary complication and facilitate extubation, non-invasive positive-pressure ventilation and continuous positive airway pressure should be used only when the patient presents acute respiratory failure [93]. High flow nasal cannula oxygen is an interesting alternative with lower gastric air aspiration, increasingly used after COVID-19 pandemic era, but not yet investigated after emergency surgery [94].

Post-operative management should be adapted to a patient’s condition. Cognitive impairment can be a consequence of MOF, benzodiazepines and anticholinergics should be avoided after delirium and neurocognitive assessment [95]. Mouth care, regular communication to the patient, and sleep hygiene care were demonstrated to reduce delirium [96, 97].

Post-operative thromboprophylaxis with low-molecular-weight heparins should be extended after discharge based on risk assessment, considering emergency surgery as a major risk and including the burden of surgery, malignancy, inflammatory bowel disease, and travel after surgery [98, 99].

In contrast to the ERAS indication in elective surgery, early removal of the urinary catheter cannot be safely achieved in this setting due to the need to monitor fluid balance in the first post-operative days in a life-threatening patient condition [100]. It may also be difficult following pelvic surgery and the resulting immobility, so the possibility of catheter removal should be evaluated daily after the critical period has passed for these patients [101].

With regard to early removal of the nasogastric tube, since the first application of the ERAS program in emergency surgery, its feasibility was demonstrated alongside the benefits of early oral nutrition [47]. In these cases, the nasogastric tube should only be used for therapeutic purposes, such as post-operative ileus or bowel edema at the end of surgery [29].

Early oral feeding was shown to be safe, even after emergency surgery [102, 103], although it is sometimes associated with episodes of mild vomiting and is also a measure to avoid post-operative ileus, in addition to mini-invasive surgery, opioid-sparing analgesia and, most importantly, optimized fluid management.

Enteral nutrition, or even mixed enteral and parenteral nutrition, is a valid alternative if the patient cannot be started on oral nutrition (e.g., if the patient is intubated) and the caloric requirements are not met [104].

Parenteral nutrition should only be started in the event of obstruction, sepsis, intestinal ischemia, high output fistula, or gastrointestinal bleeding. Adequate caloric intake should be achieved in the less invasive way possible.

In summary, rehabilitation is a crucial point to address in the emergency population, as prolonged bed rest, catabolic status worsening potential, pre-existing sarcopenia [105] and insulin resistance are common and associated with poor outcome and higher mortality. Early mobilization is strongly recommended [75].

In the emergency setting, optimization of perioperative care is even more important and, following the publication of the ERAS guidelines for emergency surgery, adherence to the ERAS pathway is even more widely recommended to improve patient outcomes.

The WSES also provided its own indication for the implementation of the ERAS protocol in a recently published position paper [106]. From their perspective, the adherence to enhanced recovery program may improve patient compliance as a chained process, which can result in reduced LHS with no increasing complication and readmission. WSES reinforced ERAS principles, adding their position about antibiotics, which should be continued after surgery for a short course only in case of complicated infections.

Pre-operative optimization is necessary, but the timing of surgery may dictate the speed of re-equilibration: WSES identified the need for a balance between immediate surgery for early resolution of acute illness and delayed surgery for improvement of the patient’s condition. The WSES paper highlights another critical issue that relates to the wide heterogeneity of protocols reported in published studies on this topic and the consequent lack of good quality evidence.

Ceresoli et al. first published their experience with a larger population after the ERAS guidelines were published [107]. Their results showed that implementation of the early recovery protocol was feasible and effective, with adherence to the items leading to a shorter LHS and fewer complications, while non-adherence was associated with delayed recovery. On regression analysis, use of laparoscopy was associated with increasing adherence to ERAS principles, whereas a negative effect was seen for the presence of hyperglycemia, fluid overload, drain placement, duration of surgery, and major complication. This study emphasized that the elements of ERAS are interconnected and the lack of one of them can reduce the effectiveness of the whole process. To implement ERAS, the Italian group suggested operative hemodynamic monitoring to reduce fluid infusion and encourage the use of inotropes to maintain the circulatory compartment, discouraged the use of drains in the absence of contamination, and emphasized the importance of pre-operative correction of hyperglycemia and the increasing use of minimally invasive approaches.

5. Enhanced recovery protocols in trauma surgery

As in the emergency setting, applying pre-operative and intra-operative ERAS considerations in trauma surgery presents challenges and limitations. These are due to factors including features’ presentation, the need for rapid intervention, surgical risk, and patient pre-existing conditions. However, some of the ERAS principles can potentially improve the outcomes, even in a trauma setting.

There is sparse literature on the implementation of an enhanced recovery program following trauma surgery. ERAS guidelines omit this scenario due to insufficient research and inadequate understanding of improvement areas.

In 2016, Moydien et al. published an analysis of the impact of their study on enhanced recovery after emergency laparotomy for penetrating abdominal trauma. Their protocol included post-operative elements, such as early removal of urinary catheters, nasogastric tubes, and intravenous lines, early oral feeding, analgesia, and early mobilization. The group of patients who received treatment following this protocol was compared to a similar group with comparable injuries who underwent treatment prior to the implementation of the new intervention. The results showed that there was good adherence to the protocol with no significant differences in complications, but patients who underwent ERP had significantly shorter LHS (5.5 ± 1.8 days vs. 8.4 ± 4.2 days, p < 0.0002). Although it was a pilot study with small sample, it demonstrated that ERAS principles could be applied effectively and safely in cases of penetrating abdominal trauma [108].

The first randomized controlled trial of ERAS application after trauma surgery was published in 2021 by Purushothaman et al. Multiple items were tested in the ERAS patient group, resulting in a reduction of 1.7 days in LHS (3.3 ± 1.3 days vs. 5 ± 1.7 days, p < 0.01) without any differences in complication or readmission. Nonetheless, this study has several limitations. First, the population selection was not comparable to the typical scenario due to the exclusion of ASA III–IV patients. Second, the ERAS milestone indication for goal-directed fluid management was not achieved and excessive amounts of colloids were given, probably resulting in four cases of ERAS failure due to paralytic ileus and vomiting after consuming solid food. On the other hand, the explanation of the trauma dynamics and their correlation with other trauma scenarios, including orthopedic, thoracic, and pelvic injuries, is very interesting in terms of its implications for pre- and post-operative management and the implementation of the ERAS pathway for these patients [109].

Uchino et al. published a scoping review on emergency abdominal surgery and trauma in 2023. They found only four studies on ERP application in the context of trauma, with only two specifically focused on trauma. All four studies aimed to evaluate the efficacy of the enhanced recovery protocol and only one trial looked exclusively at post-operative principles. The analyzed ERP items comprised:

• Pre-operative items: arterial/central line insertion, early prophylactic antibiotics, pre-anesthetic medication, nasogastric intubation, and urinary catheter insertion.

• Intra-operative items: standard anesthetic protocol, goal-directed fluid therapy, multimodal analgesia, prevention of hypothermia, and avoidance of routinary drain placement.

• Post-operative items: post-operative nutritional care, early removal of nasogastric tube, urinary catheter and drain, early mobilization and physiotherapeutic intervention, use of antibiotic, thromboembolism prophylaxis, and prevention of peptic ulcer.

The primary results of the study show a reduction in LHS, early return of bowel function, and early functional recovery using the ERAS principles. Importantly, there were no significant differences in complication rates.

Nevertheless, the authors outlined a number of issues that need to be considered in the implementation of ERAS protocols in these patients, including: necessity to manage trauma in a high-volume center with a dedicated trauma system and multidisciplinary team, high heterogeneity of the patient population and of baseline comorbidities (trauma patients vary greatly in the severity of their injuries) ranging from minor to severe trauma, a wide range of procedure complexities (trauma laparotomies cover a range of procedures from simple bowel resections to more demanding damage-control procedures) [58].

6. Conclusions

Current literature has shown that following ERAS guidelines leads to excellent outcomes in reducing post-operative complications and mortality in a wide range of elective general surgical scenarios.

Although recent studies provided good results about the possibility of reducing post-operative non-surgical and surgical complications and LHS through the application of ERAS protocols, their implementation in the context of emergency surgery may face different challenges. In particular, some aforementioned challenges are urgency/emergency of care, severity of the primary pathology requiring emergency treatment, heterogeneity of patient populations (e.g., comorbidities) and procedures, availability of resources, and the need for dedicated and highly specialized professionals (e.g., surgeons, anesthetists, ICU physicians, and nurses).

To date, the real evidence about the benefits of applying ERAS principles in emergency and trauma surgery is poor. Therefore, it appears necessary to conduct further well-designed randomized controlled trials, possibly multicenter ones, in order to confirm or not the positive results coming from the few existing studies, mainly observational ones. However, the feasibility of studies with designs having greater statistical power can prove extremely difficult due to the variability of emergency and, above all, trauma settings.

Acknowledgments

We thank Dr. Eleonora Ferretti, Head of the S.S. Clinical Trial Centre-Research and Statistics Infrastructure – Scientific Department, for her invaluable efforts in supporting research activities at our Institution.

Conflict of interest

The authors declare no conflict of interest.