The effect of different doses of neostigmine plus metoclopramide on the gastric residual volume in patients under enteral nutrition in intensive care unit

Background & Objective: Gastric motility disorder is common in patients admitted to an intensive care unit (ICU), leading to increased morbidity and mortality. We investigated the effects of different doses of neostigmine in combination with metoclopramide on gastric residual volume (GRV) in ICU patients on enteral feeding. Methods: In this double-blind clinical trial, 144 patients hospitalized in the ICU who were under enteral nutrition through nasogastric (NGT) or orogastric (OG) tube were randomly allocated to four groups. In all four groups, 20 mg of metoclopramide was prescribed IV slowly within one minute. In groups A, B, and C, 1, 1.5, and 2 mg of neostigmine were injected IV, respectively. Group D received only 20 mg of metoclopramide. All patients were gavaged every 4 h with 300 ml. The patient's head was kept at a 45° angle. To determine GRV, aspiration was done through NG tube or OG tube before the start of infusion and then at 3, 6, 9, and 12 h after the end of infusion. Results: There was no significant difference between the studied groups in terms of demographic variables such as age, blood pressure, heart rate and BMI (P > 0.05). The average difference of SOFA and APACHE and laboratory factors between the groups was not significant. The results of the comparison of the marginal averages of the residual volume of the stomach at different hours of the day showed that the amount of the residual volume at all hours had a significant average difference with each other. The addition of different doses of neostigmine had a significant effect on the residual volume of the stomach after 3 and 6 h (P < 0.05). Meanwhile, a dose of 2.0 mg of neostigmine had the most of the change 3 h after administration. Conclusion: Administration of neostigmine in combination with metoclopramide in ICU patients on enteral feeding significantly reduces the residual volume of the stomach within 12 hours after the treatment. Abbreviations: APACHE- Acute Physiology And Chronic Health Evaluation; GRV - Gastric Residual Volume; NG – Nasogastric; OG - Orogastric; SOFA- Sequential Organ Failure Assessment; VAP - ventilator-associated pneumonia Key words: APACHE; Enteral Nutrition; ICU; Metoclopramide; Neostigmine; SOFA Citation: Moshari M, Tahmasebi Z, Dahi M, Vosoughian M, Dabir S, Madadi F, Tabashi S, Ariannik M, Khatiri MAK. The effect of different doses of neostigmine plus metoclopramide on the gastric residual volume in patients under enteral nutrition in intensive care unit. Anaesth. pain intensive care 2024;28(1):33-38. DOI: 10.35975/apic.v28i1.2378 Received: August 06, 2023; Reviewed: September 11, 2023; Accepted: September 21, 2023