The effect of the enhanced recovery after surgery protocol and the reduced use of opioids on postoperative outcomes in elderly patients with colorectal cancer

<bold>Objective: </bold>The study aimed to assess the impact of the enhanced recovery after surgery (ERAS) pathways and the reduced use of opioids on postoperative outcomes in elderly colorectal cancer (CRC) patients who underwent laparoscopic surgery under general anesthesia (GA).<bold>Patients and methods: </bold>Clinical data from 99 elderly patients who underwent laparoscopic CRC surgery in the First Affiliated Hospital of Hebei North University from April 2021 to April 2023 were retrospectively analyzed and grouped based on the method of pain control measures received. Of 99 patients, 51 received conventional doses of opioid drugs (conventional group), and 48 patients were treated with reduced doses of opioids based on the principles of ERAS (low-dose group). Perioperative characteristics, postoperative pain level, cognitive function, serum biochemical index levels, and adverse reactions were compared between the two groups.<bold>Results: </bold>The first exhaust time, defecation time, and bedtime activity time of the low-dose group were compared to the conventional group (p<0.05). On the first day after the surgery, the mini-mental state examination (MMSE) score of the low-dose group was higher than the conventional group (p<0.05). After the surgery, the levels of serum brain-derived neurotrophic factor (BDNF) decreased in both groups, while the levels of neuron-specific enolase (NSE) and 5-hydroxytryptamine (5-HT) increased. However, compared to the conventional group, the low-dose group had higher levels of BDNF and lower levels of NSE and 5-HT (p<0.05). The incidence of adverse reactions in the low-dose group was lower than that in the conventional group (p<0.05).<bold>Conclusions: </bold>ERAS protocol and the reduced use of opioid drugs in CRC patients who underwent surgery under GA is associated with an analgesic effect that is comparable to that of conventional opioid use. Reduced dosage of opioid drugs lessened cognitive impairment and lowered the incidence of adverse reactions in surgical patients with CRC.