NCT07533552

Brief Summary

This study addresses the high prevalence (66%-70%) of thirst among intensive care unit (ICU) patients with endotracheal intubation, a symptom associated with oral mucosal dryness, nil per os (NPO) status, oxygen therapy, and medication effects. Unrelieved thirst may contribute to anxiety, delirium, and unplanned extubation. Current clinical practices, such as cold water or saline sprays, generally provide only short-term relief, while direct oral water administration may increase the risk of choking or aspiration. Enzyme-based saliva substitutes, which mimic components of natural saliva and may help maintain oral moisture, show potential benefits; however, evidence in ICU populations remains limited. This randomized controlled trial with blinded outcome assessment was conducted in a surgical ICU at a medical center in southern Taiwan. Eligible participants were adult patients (≥18 years) with endotracheal intubation expected to exceed 24 hours, a baseline thirst intensity score (NRS-I) ≥3, and the ability to communicate. A total of 76 participants were randomly assigned in a 1:1 ratio to either the experimental group (enzyme-based oral spray) or the control group (distilled water spray), using sequentially numbered, opaque, sealed envelopes (SNOSE) to ensure allocation concealment. The intervention was administered following routine oral care within a standardized time window (13:00-15:00). Both solutions were prepared in identical opaque spray bottles using standardized procedures. Participants were not informed of their group allocation; however, because sensory characteristics after oral administration could differ between the two solutions, complete participant blinding could not be assured. Outcome assessments were performed by trained research nurses who were blinded to group allocation. The protocol included 12 sprays per session (approximately 1.56 mL), delivered to four standardized intraoral sites, with outcomes monitored over a 4-hour period. Thirst intensity was measured using the Numerical Rating Scale-Intensity (NRS-I), and thirst distress was measured using the Numerical Rating Scale-Distress (NRS-D). Both outcomes were assessed at baseline (T0) and at 30, 60, 120, and 240 minutes post-intervention (T1-T4) by blinded outcome assessors to evaluate changes in thirst symptoms and the persistence of symptom relief over time. No biological specimens were collected; data were obtained from self-reported measures and electronic medical records, with strict de-identification and secure storage procedures. This study was considered minimal risk. Predefined safety criteria required immediate discontinuation of the intervention if adverse events such as discomfort, choking, respiratory deterioration, or other clinically significant events occurred. Data were analyzed using generalized estimating equations (GEE) to evaluate group, time, and group-by-time interaction effects while accounting for correlations among repeated measurements. The study aimed to provide evidence to inform thirst management, enhance patient comfort, and support clinically feasible nursing care for patients with endotracheal intubation in critical care settings.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
76

participants targeted

Target at P50-P75 for not_applicable

Timeline
Completed

Started Apr 2026

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

April 10, 2026

Completed
Same day until next milestone

Study Start

First participant enrolled

April 10, 2026

Completed
6 days until next milestone

First Posted

Study publicly available on registry

April 16, 2026

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

August 15, 2026

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

August 15, 2026

Completed
Last Updated

September 17, 2026

Status Verified

April 1, 2026

Enrollment Period

4 months

First QC Date

April 10, 2026

Last Update Submit

September 13, 2026

Conditions

Keywords

Enzyme-Based Oral SprayThirstEndotracheal Intubation

Outcome Measures

Primary Outcomes (1)

  • Thirst Intensity (NRS-I)

    Thirst intensity measured using the Numerical Rating Scale for Thirst Intensity (NRS-I), ranging from 0 (no thirst) to 10 (worst possible thirst). Assessments will be conducted at baseline (T0) and at 30 minutes (T1), 60 minutes (T2), 120 minutes (T3), and 240 minutes (T4) post-intervention.

    Baseline (T0) to 240 minutes post-intervention

Secondary Outcomes (1)

  • Thirst Distress (NRS-D)

    Baseline (T0) to 240 minutes post-intervention

Study Arms (2)

Enzyme-based Oral Spray Group

EXPERIMENTAL

Participants in this group will receive an enzyme-based oral spray (Oral7®) following routine oral care. The intervention will be administered using a standardized protocol, including application to four intraoral sites with a total of 12 sprays per session.

Other: Enzyme-based oral spray (Oral7®)

Distilled Water Spray Group

PLACEBO COMPARATOR

Participants in this group will receive distilled water oral spray administered at the same frequency, procedure, and time points as the experimental group following routine oral care.

Other: Distilled water oral spray

Interventions

An enzyme-based saliva substitute containing bioactive components such as lysozyme and lactoperoxidase, designed to mimic natural saliva, enhance oral moisture retention, and stabilize the oral microenvironment.

Enzyme-based Oral Spray Group

Distilled water administered via oral spray to provide moisture to the oral cavity, serving as a comparator for the enzyme-based oral spray.

Distilled Water Spray Group

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Adult patients aged ≥18 years admitted to the intensive care unit (ICU) with endotracheal intubation, and an expected duration of intubation \>24 hours.
  • Thirst intensity score ≥3 on the Numerical Rating Scale for Thirst Intensity (NRS-I).
  • Conscious and able to communicate subjective sensations verbally (Mandarin or Taiwanese) or in written form.
  • Richmond Agitation-Sedation Scale (RASS) score between -1 and +1.
  • Willingness to participate and provision of written informed consent after a full explanation of the study.

You may not qualify if:

  • Known allergy to enzyme spray components (e.g., lysozyme, lactoperoxidase, glucanase, xylitol).
  • Known allergy to milk or eggs.
  • Pre-existing xerostomia.
  • Presence of oral mucosal ulcers or active oral bleeding.
  • History of oral surgery.
  • Physician-diagnosed abnormal salivary secretion.
  • Physician-determined increased risk of aspiration or other complications associated with oral spray administration.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Chi Mei Medical Center

Tainan, Tainan City, 710, Taiwan

Location

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, OUTCOMES ASSESSOR
Masking Details
Participants were not informed of their group allocation, and both interventions were administered using identical opaque spray bottles and standardized procedures. Outcome assessors were blinded to group allocation. Because sensory characteristics after oral administration could differ between the two solutions, complete participant blinding could not be assured. The intervention administrator was not fully masked and did not participate in outcome assessment.
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR INVESTIGATOR
PI Title
Head Nurse

Study Record Dates

First Submitted

April 10, 2026

First Posted

April 16, 2026

Study Start

April 10, 2026

Primary Completion

August 15, 2026

Study Completion

August 15, 2026

Last Updated

September 17, 2026

Record last verified: 2026-04

Data Sharing

IPD Sharing
Will not share

Locations