Postoperative GI Dysfunction and Nutrition in Malnourished Cancer Surgery Patients (GIDNUT)

Gastrointestinal Dysfunction, Nutritional Status, and Delirium in the Early Postoperative Period in Oncologic Surgical Patients With Pre-existing Malnutrition: A Prospective Two-Center Observational Cohort Study

This is a prospective two-center observational cohort study in adult patients undergoing major abdominal and/or pelvic oncologic surgery with pre-existing malnutrition. The study describes the course of postoperative gastrointestinal dysfunction and evaluates whether real-world exposure to parenteral serotonin as part of routine postoperative care is associated with a higher proportion of patients whose gastrointestinal dysfunction regresses to LIFE score less than or equal to 1 by postoperative day 5 (plus or minus 1 day), compared with patients not exposed to serotonin.

All treatment decisions, including the use of parenteral serotonin, metoclopramide, neostigmine, nutritional support, and other postoperative management, are made solely by the treating physicians in accordance with routine clinical practice. The protocol does not assign, randomize, require, or restrict any drug treatment; it records real-world care, daily LIFE assessments during postoperative days 1 through 7, nutritional status measures, body composition where available, delirium screening, complications, length of stay, and mortality.

Study Overview

• Status: Not yet recruiting
• Conditions: Malnutrition; Gastrointestinal Dysfunction; Abdominal Neoplasm; Pelvic Neoplasm; Delirium - Postoperative
• Intervention / Treatment: Drug: Serotonin (e.g., serotonin adipinate); Drug: Standard Prokinetic Therapy (excluding serotonin)

Detailed Description

Disease-related malnutrition and sarcopenia are common in patients undergoing major abdominal or pelvic oncologic surgery and are associated with worse postoperative outcomes, including more complications, prolonged hospital stay, and increased mortality. Postoperative gastrointestinal dysfunction may further impair tolerance of enteral nutrition and delay recovery, especially in patients with baseline malnutrition.

In routine practice at the participating centers, postoperative gastrointestinal dysfunction or functional ileus may be managed with different pharmacologic approaches, including metoclopramide, neostigmine, and in some patients parenteral serotonin. The choice of therapy, dose, timing, and duration is determined entirely by the treating clinicians according to routine care, approved labeling, and local institutional practice; no treatment is assigned by the protocol.

This study prospectively enrolls approximately 120 adult patients with histologically or cytologically confirmed malignancy who are scheduled for major abdominal and/or pelvic oncologic surgery and have pre-existing malnutrition defined by NRS-2002 score at least 3 plus at least one phenotypic and one etiologic GLIM criterion. Participants are observed from the preoperative period through discharge or postoperative day 30, whichever occurs first.

Exposure cohorts are defined after inclusion according to whether parenteral serotonin was actually received during the early postoperative period as part of routine care. The primary endpoint is the proportion of participants with regression of gastrointestinal dysfunction to LIFE score less than or equal to 1 by postoperative day 5 within the postoperative day 4 to 6 assessment window.

Secondary outcomes include the trajectory of LIFE scores during postoperative days 1 to 7, time to restoration of gastrointestinal motility, time to achievement of at least 60 to 70 percent of calculated energy requirements via enteral nutrition, changes in nutritional status and body composition, delirium incidence and duration, postoperative complications graded by Clavien-Dindo, infectious complications, ICU and hospital length of stay, and mortality. The study is exploratory and is intended to characterize real-world postoperative trajectories and generate effect-size estimates for future studies rather than provide definitive proof of treatment superiority.

• Study Type: Observational
• Enrollment (Estimated): 120

Contacts and Locations

• Study Contact: Name: Igor Vrublevskii; Phone Number: +79672769997; Email: tender@ph-arma.ru

Study Locations

• Russia
  • Saint Petersburg, Russia, 194291
    • North-Western District Scientific and Clinical Center named after L.G. Sokolov, FMBA of Russia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Adult patients (≥18 years) with histologically or cytologically confirmed abdominal or pelvic malignancy scheduled for major oncologic surgery (radical or cytoreductive), with pre existing malnutrition (NRS 2002 ≥3 and ≥1 phenotypic + ≥1 etiologic GLIM criterion), and expected postoperative hospital stay ≥7 days.

Description

Inclusion Criteria:

• Age ≥ 18 years.
• Histologically confirmed malignant tumor of the abdomen or pelvis with planned radical or cytoreductive surgery.
• Baseline malnutrition defined as NRS2002 ≥ 3 and at least one phenotypic and one etiologic GLIM criterion.
• Expected postoperative hospitalization ≥ 7 days.
• Ability to undergo baseline cognitive and nutritional assessments (MoCA, NRS2002, GLIM, PG-SGA) prior to surgery.
• Signed informed consent for participation and data collection.

Exclusion Criteria:

• Severe decompensated hepatic or renal failure rendering surgery infeasible.
• Documented preexisting severe cognitive impairment or dementia precluding valid postoperative cognitive/delirium assessment (e.g., MoCA < 18 or documented dementia).
• Pregnancy or breastfeeding.
• Participation in another interventional randomized clinical trial within the prior 30 days that could confound outcomes.
• Inability to ensure postoperative follow-up or reliable data collection (planned transfer without access, loss of contact).

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Serotonin Cohort; Participants who receive parenteral serotonin, such as serotonin adipinate, at any time during the early postoperative period as part of routine clinical management of postoperative gastrointestinal dysfunction or functional ileus, at the discretion of the treating physician. Exposure is observed and recorded; it is not assigned by protocol.	Drug: Serotonin (e.g., serotonin adipinate); Parenteral serotonin administered postoperatively per treating physician's discretion. Dose, duration, and co-administration with other prokinetics recorded.
No Serotonin Cohort; Participants who do not receive parenteral serotonin during the index hospitalization. Other standard prokinetic agents, including metoclopramide or neostigmine, may be used according to routine clinical care. Exposure is observed and recorded; it is not assigned by protocol.	Drug: Standard Prokinetic Therapy (excluding serotonin); Use of metoclopramide, neostigmine, or other prokinetics per local practice, without serotonin.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants with LIFE ≤ 1 by postoperative day 5 (POD5 ±1 day)	The proportion of participants whose gastrointestinal dysfunction regresses to a Lausanne Intestinal Failure Estimation (LIFE) score of ≤1 within the assessment window (POD4-POD6). LIFE is assessed once daily from POD1 through POD7 using routine clinical parameters.	Postoperative day (POD) 5 ± 1 day (assessment window POD4-POD6)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean LIFE score from postoperative day 1 through postoperative day 7	Average of daily LIFE scores measured once per day from POD1 to POD7. LIFE is a composite clinical score of gastrointestinal dysfunction. Mean LIFE over this period will be compared between serotonin exposed and non exposed cohorts to describe the trajectory of GI function.	Postoperative Days 1-7
Time to restoration of gastrointestinal motility (first spontaneous bowel movement without clinical signs of significant GID)	Number of days from surgery to the first documented spontaneous bowel movement without clinically significant ongoing gastrointestinal dysfunction (as judged by the treating team and LIFE score).	From the date of surgery until the date of the first documented spontaneous bowel movement without clinically significant gastrointestinal dysfunction, assessed up to 30 days after surgery
Number of participants with at least one episode of delirium	Proportion of participants with at least one positive delirium assessment using CAM ICU or ICDSC during ICU and ward stay.	From postoperative day 0 through postoperative day 10 after surgery or until hospital discharge, whichever occurs first.
Number of delirium days	Total number of calendar days with positive CAM-ICU or ICDSC assessments.	From postoperative day 0 through postoperative day 10 after surgery or until hospital discharge, whichever occurs first.
Frequency of surgical complications (Clavien-Dindo, grade II-V)	Proportion of participants who develop at least one postoperative complication of Clavien-Dindo grade II or higher; separate reporting of grade III-V complications.	Up to 30 days after surgery
Frequency of infectious complications	Proportion of participants with clinically diagnosed infectious complications (e.g., surgical site infection, pneumonia, intra abdominal abscess, sepsis) during the index hospitalization.	Up to 30 days after surgery
ICU length of stay (days) and hospital length of stay (days)	Number of days spent; in the ICU during the index postoperative stay; in the hospital for the index surgical admission.	Up to 30 days after surgery
In-hospital mortality and 30-day mortality	Proportion of participants who die; before discharge from the index hospitalization; within 30 days after surgery, based on hospital records and, where available, follow up information.	Up to 30 days after surgery
Safety outcomes (CTCAE v6.0)	Incidence of cardiovascular, hematologic, metabolic, and neuropsychiatric adverse events with emphasis on thrombotic events, serious arrhythmias, severe hypertensive reactions, and events compatible with serotonin syndrome	From the index hospitalization through 30 days after surgery

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in body weight	Difference in body weight (kg) between baseline and discharge.	From preoperative baseline to hospital discharge, assessed up to 30 days after surgery.
Change in mid-upper arm circumference	Difference in mid upper arm circumference (cm) as a simple anthropometric marker of muscle mass.	From preoperative baseline assessment to the day of hospital discharge, assessed up to 30 days after surgery
Change in fat-free mass (FFM)	Difference in FFM (kg) between baseline and postoperative day 6-10 (or discharge). For participants in whom bioelectrical impedance analysis (BIA) is performed as part of extended clinical assessment.	Postoperative Day 6-10 or at hospital discharge, whichever occurs first
Change in skeletal muscle mass (SMM)	Difference in SMM (kg) between baseline and postoperative day 6-10 (or discharge). For participants in whom bioelectrical impedance analysis (BIA) is performed as part of extended clinical assessment.	Postoperative Day 6-10
Change in skeletal muscle mass index (SMMI)	Difference in SMMI (kg/m²) between baseline and postoperative day 6-10 (or discharge). For participants in whom bioelectrical impedance analysis (BIA) is performed as part of extended clinical assessment.	Postoperative Day 6-10 or at hospital discharge, whichever occurs first
Change in phase angle	Difference in phase angle (degrees) between baseline and postoperative day 6-10 (or discharge).For participants in whom bioelectrical impedance analysis (BIA) is performed as part of extended clinical assessment.	Postoperative Day 6-10 or at hospital discharge, whichever occurs first
Change in Nutritional Risk Screening 2002 (NRS-2002) score from baseline to discharge	Difference in Nutritional Risk Screening 2002 (NRS-2002) total score between baseline (preoperative assessment) and the day of hospital discharge. The NRS-2002 total score ranges from 0 to 7; higher scores indicate greater nutritional risk. For reporting, present mean (SD) change and number (%) of participants with clinically relevant change (e.g., change ≥1 point).	From preoperative baseline assessment to the day of hospital discharge, assessed up to 30 days after surgery
Change in Global Leadership Initiative on Malnutrition (GLIM) malnutrition severity category from baseline to discharge	Change in malnutrition severity category as defined by the Global Leadership Initiative on Malnutrition (GLIM) criteria between the preoperative baseline assessment and the day of hospital discharge. GLIM categories to be reported: No malnutrition, Moderate malnutrition, Severe malnutrition. For results reporting, present the number and proportion of participants in each GLIM category at baseline and at discharge, and the number and proportion of participants with a change in category (e.g., Moderate → Severe, Severe → Moderate, Any worsening, Any improvement).	From preoperative baseline assessment to the day of hospital discharge, assessed up to 30 days after surgery
Change in Patient-Generated Subjective Global Assessment (PG-SGA) total score from baseline to discharge	Difference in Patient-Generated Subjective Global Assessment (PG-SGA) total score between baseline (preoperative assessment) and the day of hospital discharge. PG-SGA is a validated nutritional assessment instrument; higher total scores indicate worse nutritional status. For results reporting, present mean (SD) change and median (IQR), and report the number and proportion of participants with a clinically meaningful change (predefined in the SAP; e.g., change ≥2 points).	From preoperative baseline assessment to the day of hospital discharge, assessed up to 30 days after surgery
Time to achievement of enteral nutrition ≥60-70% of calculated energy requirement	Number of days from initiation of postoperative nutritional support to the first day on which ≥60-70% of calculated daily energy requirements are delivered via the enteral route, sustained according to local practice. Calculated energy targets follow institutional nutritional protocols (typically ~25-30 kcal/kg/day).	From initiation of postoperative nutritional support up to 30 days after surgery

Collaborators and Investigators

• Sponsor: Arma Ltd.

Study record dates

Study Major Dates

• Study Start (Estimated): October 1, 2026
• Primary Completion (Estimated): October 31, 2028
• Study Completion (Estimated): March 1, 2029

Study Registration Dates

• First Submitted: April 18, 2026
• First Submitted That Met QC Criteria: May 31, 2026
• First Posted (Actual): June 3, 2026

Study Record Updates

• Last Update Posted (Actual): June 3, 2026
• Last Update Submitted That Met QC Criteria: May 31, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Postoperative Complications; Pathologic Processes; Nutrition Disorders; Neoplasms by Site; Neoplasms; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Delirium; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Emergence Delirium; Malnutrition; Pelvic Neoplasms; Abdominal Neoplasms; Organic Chemicals; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Biological Factors; Amines; Indoles; Autacoids; Inflammation Mediators; Biogenic Monoamines; Biogenic Amines; Tryptamines; Serotonin; serotonin adipinate
• Other Study ID Numbers: ARMA-GIDNUT-O-2026-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD might not be shared due to national law

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No