High VS Low Flow Nasal O2 for Acute Hypercapnic Respiratory Failure

Not Applicable

• Conditions: Acute Hypercapnic Respiratory Failure; Acute Exacerbation of COPD
• Interventions: Device: High flow nasal therapy; Device: Low flow oxygen

• Registration Number: NCT04640948
• Lead Sponsor: Belfast Health and Social Care Trust

Brief Summary

Chronic lung conditions such as smoking related lung damage lead to breathing fail. This results in accumulation of gases such as carbon-di-oxide in the body especially during periods of illness known as exacerbation.

Current management of carbon-di-oxide accumulation is administration of oxygen, nebulisers, antibiotics etc and if necessary, provide a tight fitting mask around the face to provide breathing support. If this fails, then a patient is placed on a mechanical ventilator. The tight fitting mask therapy is also called non-invasive ventilation and is used widely but patients acceptability of the therapy is limited.

Providing a high flow of air with some oxygen could potentially provide the same benefit of the non-invasive ventilation and may also be better accepted by patients.

Currently the knowledge and evidence from studies suggest a beneficial role for this high flow therapy but this has not been investigated in well designed studies.

In the proposed study we aim to investigate whether use of the high flow therapy reduces the need for non-invasive ventilation in patients who present with a recent onset accumulation of carbon-di-oxide in their body due to long-term lung disease. If this shows benefit, it will lead to a bigger trial with patient benefiting by reduction in the non-invasive ventilation or indeed a need for an invasive breathing machine.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-09-11
• Study First Submitted QC: 2020-11-20
• Study First Posted: 2020-11-23
• Study Start: 2021-06-13
• Status Verified: 2022-04
• Last Update Submitted: 2022-04-14
• Last Update Posted: 2022-04-21
• Primary Completion: 2023-03
• Study Completion: 2023-03

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 82

Inclusion Criteria

1. Adult patients > 18 years of age
2. Acute Hypercapnic respiratory failure with pH < 7.35 and pCO2 > 6 KPa

Exclusion Criteria

1. Age < 18 years
2. Pregnant or Breast-Feeding
3. Patient cannot read and understand English
4. Hypercapnia secondary to a drug toxicity or non-pulmonary aetiology
5. Hypercapnia secondary to exacerbation of asthma
6. Contraindication to NIV
7. Contraindication to HFNC
8. Not for escalation to NIV
9. pH < 7.15
10. GCS 8 or less
11. Shock defined as systolic < 90 mmHg or a reduction by 20mmHg from usual systolic BP despite volume resuscitation
12. Respiratory or cardio-respiratory arrest
13. Any other indication that requires immediate invasive/non-invasive mechanical ventilation

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
High flow nasal therapy (HFNT)	High flow nasal therapy	Characterized by an elevated arterial CO2 (PaCO2) level of \> 6kPa due to ventilatory failure. The ventilatory failure relates to the imbalance between the respiratory demand and the capacity of the respiratory system to match the demand.
Low flow oxygen (LFO)	Low flow oxygen	Characterized by an elevated arterial CO2 (PaCO2) level of \> 6kPa due to ventilatory failure. The ventilatory failure relates to the imbalance between the respiratory demand and the capacity of the respiratory system to match the demand.

Primary Outcome Measures

Name	Time	Method
Proportion of patients requiring NIV in each cohort	6 hours	Proportion of patients who require NIV by 6 hours of intervention.

Secondary Outcome Measures

Name	Time	Method
Respiratory rate (Breath/minute)	At 1 hour, 6 hours and 24 hours.	Rate of breathing per minute as documented in medical notes.
Hospital length of stay	From the date of randomization until hospital discharge or date of death from any cause, whichever came first, assessed up to 12 weeks.
Heart rate (Beat/minute)	1 hour, 6 hours and 24 hours.	Heart rate per minute as documented in medical notes.
Mean arterial pressure in millimeters of mercury	1 hour, 6 hours and 24 hours.	Mean arterial pressure in millimeters of mercury as documented in medical notes
In-hospital mortality	From the date of randomization until the date of death or hospital discharge, whichever came first, assessed up to 12 weeks.
ICU length of stay	From the date of ICU admission until the date of last documented ICU discharge or date of death from any cause, whichever came first, assessed up to 12 weeks.
PaO2 in Kilopascal	1 hour, 6 hours and 24 hours.	Blood arterial PaO2 level measured at the pre-specified time-points or at the nearest time-point.
pH	1 hour, 6 hours and 24 hours.	pH measured for acid-base status.
Intubation rate	1 hour, 6 hours and 24 hours.
ICU admission	From the date of randomization until the date of first documented admission to ICU, assessed up to 12 weeks.
PaCO2 in Kilopascal	1 hour, 6 hours and 24 hours.	Blood arterial PCO2 level measured at the pre-specified timepoints or at the nearest timepoint.
Dyspnoea	1 hour, 6 hours and 24 hours.	Dyspnoea will be assessed assessment using a visual analogue scale (VAS), score range 0-10, higher values represent a better outcome)) if patient has capacity or the Likert scale (score range 1-5; higher values represent a better outcome) to be completed by the clinical team (doctor/nurse/physio) if the patient lacks capacity.
Patient comfort	1 hour.	Comfort will be assessed assessment using a visual analogue scale (VAS), score range 0-10, higher values represent a better outcome)) if patient has capacity or the Likert scale (score range 1-5; higher values represent a better outcome) to be completed by the clinical team (doctor/nurse/physio) if the patient lacks capacity.

Trial Locations

Locations (2)

Mater Hospital; 🇬🇧 Belfast, United Kingdom

Royal Victoria Hospital; 🇬🇧 Belfast, United Kingdom