"The Effect of Abdominal Massage on Gastrointestinal Functions in Mechanically Ventilated Patients Receiving Enteral Nutrition in Intensive Care"

Intensive care units (ICUs) are areas where advanced technologies and multidisciplinary care are provided together to sustain and treat critically ill patients. Patients treated in the ICU due to reasons such as inadequate gas exchange, increased respiratory workload, and inability to maintain airway patency are intubated and placed on mechanical ventilation support. ICU patients dependent on mechanical ventilators become reliant on external nutrition during the treatment process as they cannot meet their nutritional needs. In ICU patients, damage to the digestive mucosa due to stress may occur, leading to various gastrointestinal (GI) problems such as increased residual volume, diarrhea, constipation, and malnutrition. Therefore, providing accurate and adequate nutritional support is critically important in the treatment processes of ICU patients. In recent years, nutritional support has been included among therapeutic methods in ICUs. Studies have shown that appropriately timed nutritional support positively affects the clinical outcomes of patients in intensive care units. Enteral or parenteral nutrition methods can be chosen based on the patient's health status and guidelines.

For ICU patients on mechanical ventilator support, if the gastrointestinal tract is functional, enteral nutrition is frequently preferred. Enteral nutrition is the delivery of nutrients to the stomach or small intestine via a tube, catheter, or stoma. Enteral nutrition is a commonly used method for patients who cannot eat orally. It can reduce infection risk, shorten catabolic responses, the formation of gastric ulcers, and the length of hospital stay. Starting enteral nutrition within the first 48 hours for patients admitted to the ICU has been reported to shorten hospital stay and reduce mortality rates.

Although enteral nutrition has high physiological response rates, there are also risks and potential side effects. The most common GI complications encountered in patients receiving enteral nutrition are gastrointestinal complications. GI complications in enteral nutrition are influenced by many factors, including the patient's general condition, mechanical ventilation, hemodynamic parameters, and administered medications. These complications include aspiration, diarrhea, constipation, abdominal distension, and nausea/vomiting. These side effects have been observed in 62% of patients receiving this type of nutrition. Constipation is a digestive system complication that is often overlooked in ICU patients. Immobility, hypotension, the use of vasopressors and narcotics, and lack of access to appropriate conditions and facilities are among the reasons for constipation development. Constipation prolongs the duration of mechanical ventilation and increases the length of stay in ICUs. In a study evaluating enteral nutrition complications, 48.5% of the patients experienced dislodgement of their nasogastric tube, 45.5% had electrolyte imbalances, 34.5% developed hyperglycemia, 32.8% had diarrhea, 29.7% experienced constipation, 20.4% had vomiting, and 3.1% developed pulmonary aspiration.Another study found that 32% of ICU patients receiving enteral nutrition experienced increased gastric residual volume, while 46% developed gastrointestinal intolerance.

GI problems encountered in ICUs can be prevented, reduced, and patient comfort can be increased through pharmacological and non-pharmacological treatments (abdominal massage, aromatherapy, acupuncture, mobilization, etc.). A study investigating nutrition and motility issues in ICUs found that non-pharmacological methods, alongside pharmacological approaches, were also emphasized, with abdominal massage applied in 39% of cases to address motility problems. Non-pharmacological methods have various advantages over pharmacological approaches. The most important advantage of these methods is that they can be easily applied to individuals. Additionally, they offer a more cost-effective solution in terms of both patient and hospital costs.

Abdominal massage, which aims to stimulate and increase intestinal peristalsis, is performed by applying effleurage, petrissage, and vibration techniques clockwise on the abdomen for 15-20 minutes. Abdominal massage, performed by nurses, caregivers, or family members, is a safe, non-invasive method with no known side effects. This massage has been shown to be effective for those experiencing defecation issues, abdominal pain caused by gas or cramps, individuals with altered abdominal muscle tone, and those suffering from fecal incontinence or chronic constipation. Studies evaluating the effectiveness of abdominal massage in preventing GI complications in ICUs are relatively limited. A study found that abdominal massage was effective in reducing constipation and improving quality of life.A study on patients receiving enteral nutrition in neurology and neurosurgery clinics stated that abdominal massage could be used to prevent abdominal distension and increased gastric residual volume (GRV). According to a study conducted in Germany, it was reported that abdominal massage began to be used to improve GI complications in 38.8% of ICU patients.

There are studies in the literature examining the effects of abdominal massage on gastrointestinal system functions. Existing studies generally focus on the effects of abdominal massage on geriatric patient populations or evaluate it in intensive care patients with limited parameters. However, this research will specifically investigate the effects of abdominal massage on gastrointestinal system functions in patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit. The findings of this study will contribute to the adoption and standardization of abdominal massage practices by intensive care nurses in the care of this specific patient group, supported by scientific evidence. To contribute to this area in the literature, the study aims to evaluate the effects of abdominal massage on gastric residual volume, frequency of defecation, and abdominal distension in mechanically ventilated patients receiving enteral nutrition in the intensive care unit.

Three different sets of hypotheses have been established in the study. These are:

First Hypothesis Set H0: Abdominal massage applied to patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit has no effect on the frequency of defecation.

H1: Abdominal massage applied to patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit has an effect on the frequency of defecation.

Second Hypothesis Set H0: Abdominal massage applied to patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit has no effect on abdominal distension.

H1: Abdominal massage applied to patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit has an effect on abdominal distension.

Third Hypothesis Set H0: Abdominal massage applied to patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit has no effect on gastric residual volume.

H1: Abdominal massage applied to patients who are mechanically ventilated and receiving enteral nutrition in the intensive care unit has an effect on gastric residual volume.

Method\* Type of Research The study is designed as a prospective, single-blind randomized controlled trial to determine the effects of abdominal massage on gastrointestinal system functions (frequency of defecation, abdominal distension, gastric residual volume) in mechanically ventilated patients receiving enteral nutrition in the intensive care unit. The research is prepared based on the 25-item checklist and flowchart included in the "Consolidated Standards of Reporting Trials (CONSORT-2017)." The study's Clinical Trials protocol registration will be done via ClinicalTrials.gov.

Location and Characteristics of the Research The research will be conducted at Mersin Toros State Hospital's general and surgical intensive care units between between January 2025 and August 2025. The internal intensive care unit at Mersin Toros State Hospital has 9 beds, while the surgical intensive care unit has 10 beds. The general intensive care unit consists of two separate rooms, with the first room containing 2 isolation rooms and a 3-bed ward system, and the second room having a 4-bed ward system separated by a wall. There are 22 nurses working in the general intensive care unit. The surgical intensive care unit is located in a single room with a 9-bed ward system, separated by walls and includes 1 isolation room. There are 24 nurses in the surgical intensive care unit, and health personnel from both units provide shared services, including a total of 8 clinical support staff, 6 cleaning staff, 1 attendant, 1 security personnel, and 1 medical secretary. The same physicians are on duty in both intensive care units, totaling 13 anesthesia specialists and 1 intensive care specialist. Both intensive care units are at level 3, and since enteral nutrition is administered cyclically, the patients are similar. The enteral nutrition planning for patients in the intensive care units will be done in cooperation with nutrition nurses and dietitians. The planned enteral nutrition will be administered and monitored by the nurses.

Randomization The listing of individuals forming the study sample will be done by an independent researcher who is not participating in the study. After obtaining consent from the relatives of patients who are willing to participate in the study and meet the criteria, the allocation of patients to the intervention or control group will be determined randomly using the website randomizer.org. Individuals included in the sampling will be listed from 1 to 70. The program will input the information that there will be two different groups of 35 individuals and that participants are numbered between 1 and 70. The program will randomly assign the two groups. The individuals listed by an independent researcher will be randomly numbered by the system (randomizer.org).

Blinding Due to the nature of the study, the researcher will not be blinded. Thus, the research will be conducted as a single-blind randomized controlled trial. Upon completion of the study, data will be entered into the computer by an independent researcher without specifying the intervention or control group, coded as groups A and B. Data analysis and the writing of the research report will be conducted by a statistician who does not know which group is which, using the codes A and B.

Data Collection Preparation of Data Collection Tools A "Data Collection Form" has been used in the data collection phase of the research. The data will be collected using a data collection form consisting of three sections: "Patient Clinical Condition Information Form," "Enteral Nutrition Monitoring Form," and "Bristol Stool Consistency Scale."

Patient Clinical Condition Information Form: This form containing patient clinical condition information has been prepared by the researcher to determine the socio-demographic characteristics of the participants after a review of the relevant literature. It includes an assessment of individual characteristics, the APACHE II (Acute Physiology and Chronic Health Evaluation) scoring system, and the Glasgow Coma Scale (GCS). Individual characteristics include age, gender, reason for admission to intensive care, chronic disease status, sedation status, intubation, and the start date of enteral nutrition.

APACHE II Scale: This scale is used for the evaluation of a patient's acute physiological and chronic health condition; it was developed to provide an objective assessment of the mortality risk, severity, and criticality of diseases in patients in the intensive care unit. The scoring range is between 12-71. As the score increases, the patien

• This measure will be used to determine the amount of stomach content remaining after feeding. [Срок оценки: Measured twice daily (morning and evening) over 3 days.]