[Advantages and limitations of transcutaneous electrical acupoint stimulation in the treatment of patients with severe gastrointestinal function injury in intensive care unit: a prospective randomized controlled trial].

Objective: To evaluate the advantages and limitations of transcutaneous electrical acupoint stimulation (TEAS) in the treatment of patients with severe gastrointestinal function injury in intensive care unit (ICU) by analyzing dynamic changes of intestinal fatty acid binding protein (I-FABP), D-lactic acid and citrulline.

Methods: A prospective single-center randomized controlled trial was conducted. Patients with severe gastrointestinal function injury admitted to the ICU from February 2021 to January 2024 were enrolled [age > 18 years old, acute gastrointestinal injury (AGI) grade 2 to 3, stable hemodynamics]. Patients with different AGI grades were randomly assigned in a 1:1 ratio to the TEAS group and the control group using simple randomization. Both groups received conventional treatment and enteral nutrition (EN). In addition, the TEAS group underwent TEAS at the Neiguan and Zusanli points for 30 minutes per session, twice daily for 7 days. Baseline data, including age, gender, underlying diseases, and primary diagnoses, were recorded. Three intestinal biomarkers, such as I-FABP, D-lactic acid, and citrulline were measured before and after 7 days of treatment. EN tolerance indicators and 28 days survival status were documented. The differences in various indicators were compared between the two groups, subgroup analyses were conducted based on AGI grading, and interaction between AGI grade and TEAS were analyzed. The 28-day Kaplan-Meier survival curves were generated for both groups.

Results: Finally, 133 patients were included, with 68 in the TEAS group and 65 in the control group. Baseline characteristics were comparable between the two groups. A comparison of the dynamic changes in intestinal biomarkers revealed that the I-FABP level in both groups decreased after treatment compared to pre-treatment, with a more pronounced reduction in the TEAS group. The least square mean difference (LS Mean difference) for the corrected I-FABP level between the two groups during the observation period was -0.23 μg/L [95% confidence interval (95%CI) was -0.45 to -0.01], which was statistically significant (P = 0.041). Additionally, a significant interaction with AGI was observed (P = 0.004). Post-treatment, D-lactic acid level decreased in both groups compared to pre-treatment, with a more significant reduction in the TEAS group. The LS Mean difference for the corrected D-lactic acid level was -0.08 mmol/L (95%CI was -0.11 to -0.05), which was statistically significant (P < 0.001), and the interaction with AGI was also significant (P = 0.005). There was no significant change in citrulline levels between the two groups before and after treatment. The LS Mean difference for the corrected citrulline level was -0.17 μmol/L (95%CI was -1.87 to 1.53), which was not statistically significant (P = 0.845), and no significant interaction with AGI was observed (P = 0.913). Comparison of EN tolerance parameters between the two groups revealed that the TEAS group had a longer total EN time (hours: 72±31 vs. 60±28) and higher total EN calories (kJ: 11 469.23±7 237.34 vs. 6 638.76±5 098.37), as well as a higher 70% target caloric attainment rate (52.9% vs. 32.3%) compared to the control group (all P < 0.05). The incidence of abdominal distension after EN was lower in the TEAS group than that in the control group (23.5% vs. 43.1%, P < 0.05), while the incidence of diarrhea after EN was higher in the TEAS group (22.1% vs. 7.7%, P < 0.05). There were no significantly differences in AGI grade reduction rate, post-EN vomiting/gastric retention rate, incidence of feeding interruption, and 28-day survival rate between the two groups. Furthermore, there were no significantly interaction between these observation measures and AGI. Kaplan-Meier survival analysis showed that there was no significantly difference in 28-day cumulative survival rate between the TEAS group and the control group [Log-Rank test: P = 0.501, hazard ratio (HR) = 0.81, 95%CI was 0.43-1.51), and there was no significantly interaction with AGI (P = 0.702).

Conclusions: The advantage of TEAS in the treatment of ICU patients with severe gastrointestinal function injury lies in its ability to reverse intestinal cell necrosis and promote the reconstruction of intestinal barrier function. Additionally, gastrointestinal tolerance is significantly improved, and both the duration and total calories of EN are increased. However, the limitation of TEAS therapy is that it does not promote the recovery of intestinal cell absorption and synthesis function in the target patients. Moreover, it may lead to nutrient solution overload due to improved gastrointestinal tolerance. Furthermore, TEAS does not appear to improve 28-day cumulative survival rate in the target patients.