Humidification Practices During Hospitalized Patients on Non-Invasive Ventilation

Non-invasive ventilation (NIV) provides respiratory support through a mask compared to invasive mechanical ventilation (IMV) using an endotracheal or tracheostomy tube. NIV has become a standard of care in managing acute respiratory failure, especially in acute exacerbation of chronic obstructive pulmonary disease, acute cardiogenic pulmonary edema, immunocompromised patients, and weaning from IMV. Over the past few decades, its use has increased drastically in these patients, reducing the need for IMV, morbidity, and mortality. However, various studies have reported NIV failure in 20-50% of patients owing to poor tolerance. Non-humidified inspired gases used in NIV and IMV are very dry, and their humidification can prevent their harmful effect on the respiratory system. Heat and Humidification in IMV is the standard of care worldwide, but no consensus or guidelines regarding its use during NIV. Although the upper airways are not bypassed in NIV, physiological air conditioning could be insufficient due to circuit leaks, high respiratory drive, a high fraction of inspired oxygen (FiO2), type of mask, mouth breathing, and use of dry air with ICU ventilators. Inadequate humidification in hospitalized patients with acute respiratory failure using NIV can lead to difficult intubation after NIV failure, life-threatening airway obstruction due to thick secretions, and increased airway reactivity. Based on various physiological and clinical studies, AARC clinical practice guidelines suggested humidification in patients with NIV. To date, the practice pattern of humidification during NIV is unknown.

This study aims to assess the practice pattern of physicians regarding humidification use during NIV in hospitalized adult patients. This study will recognize the gaps between current practice and available evidence.

Objective:

Primary Objective:

(a) Humidification utilization rate and their types

Secondary Objective:

• Reasons for not using humidification
• Reasons for choosing a specific humidification device

Methodology:

• Study design: This is a cross-sectional web-based survey among physicians who are dealing with NIV. Participation will be on an invitation basis and purely voluntary after informed consent.
• Inclusion criteria: Physicians dealing with adult patients with acute respiratory failure
• Exclusion criteria: Physicians who refuse to give consent
• Study Duration: six months
• Study setting: A pre-designed survey link will be sent to all members of the various respiratory and critical care societies. Each physician who consented to participate will receive a web-based questionnaire. Physicians who did not respond to the first email within eight weeks will receive reminders.
• Sample Size: As per a survey by Crimi C et al.14, humidification was used in more than 50% of clinical scenarios using NIV. We calculate our sample size by using the formula N= t.p.q/ε2 where N is equal to the required sample size, t is similar to the confidence level at 95% (standard value of 1.96), p is equal to estimated prevalence (humidification use), q is equal to 1-prevalence, ε is similar to allottable error. Using the above formula in the prevalence of 50%, our sample size is 384. We will exclude responses like not using NIV, incomplete data (>10%), and working in the same unit. We added 20% to compensate for this, so our final sample size would be 462.
• Data Analysis: Data will be collected, compiled, and analyzed using IBM-SPSS-29 software. Descriptive statistics (mean, median, and proportions) will be used to report survey questionnaire responses. The Kruskal-Walli's test will be used for non-parametric data to evaluate the variability depending on the physician's primary specialty and hospital setting.
• Consent: The invited email will have details of the study purpose and a participant information sheet. An email will also contain a Google Form link with instructions that implied consent will be considered if they agree to participate and submit their response.

Inclusion criteria

• Physicians dealing with adult patients with acute respiratory failure with NIV

Exclusion criteria

• Physicians who refuse to give consent or not using NIV