To determine if critically ill patients with acute respiratory failure treated with carbocisteine, hypertonic saline, or both, experience increased hydration of airway mucus.

Is the mechanism of action of hypertonic saline and/or carbocisteine in the treatment of patients with acute respiratory failure due to an increase in mucus hydration?

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

ISRCTN

Registry ID

ISRCTN10086050

Enrollment

360

Registered

2022-07-04

Start date

2022-08-01

Completion date

Unknown

Last updated

2026-08-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Critically ill patients with acute respiratory failure (ARF) Respiratory

Interventions

Sputum samples will be collected from patients recruited to the MARCH clinical trial (https://www.fundingawards.nihr.ac.uk/award/NIHR130454). The proposed study will involve the collection of sputum

baseline (Day 0) (at randomisation), Day 3, and Day 7. The solids concentration of mucus will be measured and dynamic rheology measurements will be recorded including G’ and G” of samples from which t

Eligibility

Sex/Gender

All

Age

16 Years to 120 Years

Inclusion criteria

Inclusion criteria: 1. Participating in the MARCH trial 2. Provide consent to have biological samples (airway secretions) collected and analysed and the data generated from these analyses to be used

Exclusion criteria

Exclusion criteria: 1. Suspected/confirmed COVID disease 2. Do not meet the MARCH trial inclusion criteria

Design outcomes

Primary

Measure	Time frame
Percentage mucus solid content (dry-to-wet weight ratio) of sputum measured from sputum samples collected at baseline and 3 days	—

Secondary

Measure	Time frame
1. Percentage mucus solid content (dry-to-wet weight ratio) of sputum measured from sputum samples collected at baseline and 7 days 2. Sputum elasticity (G’) and viscosity (G’’) (and yield stress, Tc) measured using dynamic rheology of sputum samples collected at baseline and 3 days 3. Sputum IL-6, IL-8, and 8-isoprostane levels measured by ELISA of sputum samples collected at baseline and 3 days 4. Sputum elasticity (G’) and viscosity (G’’) (and yield stress, Tc) measured using dynamic rheology of sputum samples collected at baseline and 7 days 5. Sputum IL-6, IL-8, and 8-isoprostane levels measured by ELISA of sputum samples collected at baseline and 7 days	—

Measure

Time frame

1. Percentage mucus solid content (dry-to-wet weight ratio) of sputum measured from sputum samples collected at baseline and 7 days 2. Sputum elasticity (G’) and viscosity (G’’) (and yield stress, Tc) measured using dynamic rheology of sputum samples collected at baseline and 3 days 3. Sputum IL-6, IL-8, and 8-isoprostane levels measured by ELISA of sputum samples collected at baseline and 3 days 4. Sputum elasticity (G’) and viscosity (G’’) (and yield stress, Tc) measured using dynamic rheology of sputum samples collected at baseline and 7 days 5. Sputum IL-6, IL-8, and 8-isoprostane levels measured by ELISA of sputum samples collected at baseline and 7 days

—

Countries

England, Northern Ireland, Scotland, United Kingdom, Wales

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Aug 25, 2026