The Effect of Intravenous Lidocaine, Ketamine, and Lidocaine-Ketamine Combination in Colorectal Cancer Surgery: A Randomized Controlled Trial

Point of care ultrasound of small intestine in patients undergoing laparoscopic bowel surgery: a prospective observational study

BACKGROUND

Point-of-care ultrasound (POCUS) is increasingly utilized in clinical medicine, yet its role in assessing normal postoperative bowel function remains underexplored, particularly after laparoscopic colorectal surgeries.

METHODS

A prospective cohort study of 20 laparoscopic bowel resection patients was conducted, utilizing small bowel POCUS before surgery and daily from postoperative day (POD) 1 to POD 4. Small bowel width and a Small Bowel Motility Index (SBMI) were recorded in each examination. Statistical analyses involved repeated measures ANOVA to evaluate motility and width changes over study days.

RESULTS

The small bowel motility index displayed statistically significant differences across the study days before surgery up to POD4 (P<0.001). Pairwise comparisons revealed significant differences between pre-surgery (10.58±1.31) and POD1 (8.20±2.30) with a mean difference of 2.38 (P=0.009). Subsequent days demonstrated significant differences between POD1 and POD3 (9.78±1.51) and POD4 (10.30±2.05) with mean differences of -1.58 (P=0.049) and -2.10 (P=0.029) respectively. In contrast, small bowel width did not exhibit statistical significance during this follow-up period (P=0.112).

CONCLUSIONS

Our findings underscore the dynamic nature of small bowel motility, highlighting its potential as a crucial parameter for postoperative assessment. Further larger studies with vareity of patients are warranted to explore the broader applications of small bowel POCUS in postoperative care.

Application value of dexmedetomidine in anesthesia for elderly patients undergoing radical colon cancer surgery

BACKGROUND

Colon cancer presents a substantial risk to the well-being of elderly people worldwide. With advancements in medical technology, surgical treatment has become the primary approach for managing colon cancer patients. However, due to age-related physiological changes, especially a decline in cognitive function, older patients are more susceptible to the effects of surgery and anesthesia, increasing the relative risk of postoperative cognitive dysfunction (POCD). Therefore, in the surgical treatment of elderly patients with colon cancer, it is of paramount importance to select an appropriate anesthetic approach to reduce the occurrence of POCD, protect brain function, and improve surgical success rates.

AIM

To explore the value of dexmedetomidine (Dex) in anesthesia for elderly patients undergoing radical colon cancer surgery.

METHODS

One hundred and seventeen patients with colon cancer who underwent elective surgery under general anesthesia were selected and divided into two groups: A and B. Group A received Dex before anesthesia induction, and B group received an equivalent amount of normal saline. Changes in the mini-mental state examination, regional cerebral oxygen saturation (rSO2), bispectral index, glucose uptake rate (GluER), lactate production rate (LacPR), serum S100β and neuron-specific enolase (NSE), POCD, and adverse anesthesia reactions were compared between the two groups.

RESULTS

Surgical duration, duration of anesthesia, and intraoperative blood loss were comparable between the two groups (P > 0.05). The overall dosage of anesthetic drugs used in group A, including propofol and remifentanil, was significantly lower than that used in group B (P < 0.05). Group A exhibited higher rSO2 values at the time of endotracheal intubation, 30 min after the start of surgery, and immediately after extubation, higher GluER values and lower LacPR values at the time of endotracheal intubation, 30 min after the start of surgery, immediately after extubation, and 5 min after extubation (P < 0.05). Group A exhibited lower levels of serum S100β and NSE 24 h postoperatively and a lower incidence of cognitive dysfunction on the 1st and 5th postoperative days (P < 0.05).

CONCLUSION

The use of Dex in elderly patients undergoing radical colon cancer surgery helps maintain rSO2 Levels and reduce cerebral metabolic levels and the incidence of anesthesia- and surgery-induced cognitive dysfunction.

The role of lidocaine in cancer progression and patient survival

Since its development in 1943, lidocaine has been one of the most commonly used local anesthesia agents for surgical procedures. Lidocaine alters neuronal signal transmission by prolonging the inactivation of fast voltage-gated sodium channels in the cell membrane of neurons, which are responsible for action potential propagation. Recently, it has attracted attention due to emerging evidence suggesting its potential antitumor properties, particularly in the in vitro setting. Further, local administration of lidocaine around the tumor immediately prior to surgical removal has been shown to improve overall survival in breast cancer patients. However, the exact mechanisms driving these antitumor effects remain largely unclear. In this article, we will review the existing literature on the mechanism of lidocaine as a local anesthetic, its effects on the cancer cells and the tumor microenvironment, involved pathways, and cancer progression. Additionally, we will explore recent reports highlighting its impact on clinical outcomes in cancer patients. Taken together, there remains significant ambiguity surrounding lidocaine's functions and roles in cancer biology, particularly in perioperative setting.

Trial watch: local anesthetics in cancer therapy

Preclinical evidence indicates potent antitumor properties of local anesthetics. Numerous underlying mechanisms explaining such anticancer effects have been identified, suggesting direct cytotoxic as well as indirect immunemediated effects that together reduce the proliferative, invasive and migratory potential of malignant cells. Although some retrospective and correlative studies support these findings, prospective randomized controlled trials have not yet fully confirmed the antineoplastic activity of local anesthetics, likely due to the intricate methodology required for mitigating confounding factors. This trial watch aims at compiling all published preclinical and clinical research, along with completed and ongoing trials, that explore the potential antitumor effects of local anesthetics.