Anesthesia practices in colorectal cancer surgery

In patients with colorectal cancer (CRC), factors such as increased age, comorbid disease, adverse physiopathological effects of drugs used in cancer treatment, and organ failures associated with tumor size and metastases, which increase the incidence of comorbidities and cause metabolic changes that alter pharmacokinetic and pharmacodynamic properties of anesthetic agents, make already risky anesthesia practices more challenging. These patients often have high-risk scores in the American Society of Anesthesiologists (ASA) scoring, which is used to assess anesthesia risk in the preoperative period. According to the current research, decisions made by an anesthetist in colorectal surgery such as any of the general, regional, or neuraxial anesthetic techniques, anesthetic-analgesic agents chosen and perioperative blood transfusion may have positive or negative effects on colorectal cancer recurrence or long-term survival rates. Inhalation agents of sevoflurane, desflurane, and xenon, intravenous anesthetics of propofol, analgesics of COX inhibitor nonsteroidal anti-inflammatory agents (NSAIDs), anesthetic techniques of epidural block or regional block with general anesthesia, and local anesthetics used in these blocks can be safely used in CRC patients. In addition, these anesthetic agents and techniques have the potential to produce positive effects on CRC prognosis. However, the effects of dexmedetomidine, ketamine, opioids, and β-blockers are controversial. Care should be taken in the selection and dosing of these agents. Blood transfusion and hypothermia are known to have adverse effects in all surgical procedures.