Anaemia is common in patients presenting for colorectalsurgery and increases all cause morbidity. Attempts to correct it should be made prior to surgery. Newer preparations of intravenous iron have a low risk of adverse reactions and are more effective than oral iron at restoring haemoglobin concentrations in both iron deficiency anaemia and anaemia of chronic disease. （Quality of evidence: High ；Recommendation grade: Strong）Blood transfusion has long-term effects and should be avoided if possible.（Quality of evidence: High；Recommendation grade: Strong）

Preoperative routine nutritional assessment offers the opportunity to correct malnutrition and should be offered（Quality of evidence: Low ；Recommendation grade: Strong）. Preoperatively, patients at risk of malnutrition should receive nutritional treatment preferably using the oral route for a period of at least 7–10 days（Quality of evidence: Moderate ；Recommendation grade: Strong）.

Prehabilitation shows promising results in recovery of functional capacity and may reduce complications after colorectal surgery（Quality of evidence: Moderate ）. Patients who are less fit may be more likely to benefit. Further research is required before considering this as a mandatory item in an ERAS protocol（Quality of evidence: Low ）.（Recommendation grade: Weak）

General preoperative medical assessment and optimisation is intuitively important, but for specified risk assessment tools, the evidence of their clinical accuracy remains low.（Quality of evidence:Low ；Recommendation grade: Strong）Smoking increases the risk of postoperative complications. Smoking should cease preoperatively for at least 4 weeks to reduce respiratory and wound-healing complications; shorter periods may still yield lesser benefits. Intense counselling and nicotine replacement therapy are most likely to be effective. （Quality of evidence: High ；Recommendation grade: Strong）Although meta-analyses show the impact of alcohol abuse on postoperative outcomes,only 2 small RCTs show a benefit of alcohol cessation on outcomes.（Quality of evidence:Low ；Recommendation grade: Strong）

Preoperative education can reduce patient anxiety to an acceptable level without the need for anxiolytic medication. Pharmacologic anxiolysis with long- or short-acting sedative medication (especially benzodiazepines and especially in the elderly) should be avoided if possible before surgery. Opioid-sparing multimodal re-anaesthetic medication can be used with a combination of acetaminophen, NSAIDS and gabapentanoids. All should be dose adjusted according to age and renal function. Gabapentinoids should preferably be limited to a single lowest dose to avoid sedative side effects.（Quality of evidence:Avoiding routine sedative medication: Moderate；Recommendation grade: Strong）

Patients undergoing elective colorectal surgery should be allowed to eat up until 6 h and take clear fluids including CHO drinks, up until 2 h before initiation of anaesthesia. Patients with delayed gastric emptying and emergency patients should remain fasted overnight or 6 h before surgery. No recommendation can be given for the use of CHO in patients with diabetes.（Quality of evidence:In elective colorectal surgery in patients without delayed gastric emptying; 6-h fasting for solids and 2 h for clear fluids including CHO drinks: High；CHO drinks improving well-being, insulin resistance:Moderate；CHO drinks reducing complications and improving recovery time: Low.Recommendation grade: Adherence to fasting guidelines(avoid overnight fasting): Strong;Administration of preoperative CHOs: Strong;Administration of preoperative CHOs in well-controlled diabetic and obese patients: weak)

Net “near-zero” fluid and electrolyte balance should be maintained（Quality of evidence: High ；Recommendation grade: Strong）. To cover pure maintenance needs, hypotonic crystalloids should be used (rather than isotonic crystalloids, which contain high concentrations of sodium and cations)（Quality of evidence: Low ；Recommendation grade: Strong）. For replacement of losses, saline 0.9% and saline-based solutions should be avoided, with balanced solutions being preferred（Quality of evidence: Low ；Recommendation grade: Strong（(only in hyperchloraemic and acidotic patients)））. In patients receiving epidural analgesia, arterial hypotension should be treated with vasopressors after ensuring the patient is normovolaemic.

The goal of perioperative fluid therapy is to maintain fluid homoeostasis avoiding fluid excess and organ hypoperfusion. Fluid excess leading to perioperative weight gain more than 2.5 kg should be avoided, and a perioperative near-zero fluid balance approach should be preferred.（Quality of evidence:High ；Recommendation grade: Strong） GDFT should be adopted especially in high-risk patients and in patients undergoing surgery with large intravascular fluid loss (blood loss and protein/fluid shift). （Quality of evidence: Moderate ；Recommendation grade: Strong in high-risk patients and for patients undergoing surgery with large intravascular fluid loss (blood loss and protein/fluid shift）；Weak in low-risk patients and in patients undergoing low-risk surgery）Inotropes should be considered in patients with poor contractility (CI ＜ 2.5 L/min).

Patients undergoing major colorectal surgery should have (I) mechanical thromboprophylaxis by well-fitting compression stockings and/or intermittent pneumatic compression until discharge（Quality of evidence: Postoperative mechanical thromboprophylaxis: High; In-hospital or until mobilised: Moderate ；Recommendation grade: Strong） and (II) receive pharmacological prophylaxis with LMWH once daily for 28 days after surgery. LMWH In-hospital or 7 days postop（Quality of evidence: Low ；Recommendation grade: Weak）；LMWH until 28 days postop（Quality of evidence: Low ；Recommendation grade: Strong）.

Reliable temperature monitoring should be undertaken in all colorectal surgical patients and methods to actively warm patients to avoid IPH should be employed.（Quality of evidence: Maintenance of normothermia: High ；Monitoring of temperature: High ；Prewarming: Moderate ；Recommendation grade: Strong）