Impact of Aerosol Generation on Non-invasive Respiratory Support Modalities

Introduction:

Respiratory health is very important. In the case of diseases, support is needed. Not every case needs ventilation and is invasive. The advent of non-invasive support systems has changed the direction of respiratory care. Effective treatment is provided without needing to go for invasive procedures. However, these have the potential risk of generating aerosols. Aerosols are mainly minute particles that can carry secretions of the respiratory system, which can often contain infectious agents. These can cause diseases and aid in their spread to healthcare workers and surrounding areas. This article aims to list the various non-invasive respiratory support modalities that generate aerosols, emphasizing prevention.

What Is Aerosol?

Aerosol is a liquid or solid airborne particle up to approximately 100 micrometers; they have a longer lingering time in the air than larger droplets of infection Under gravitational force, they follow a ballistic trajectory. It is one of the important transmission routes for respiration. They can be leaked out into the air during patient exhalation if the mask interface is leaking. Most of these particles are infectious, making their prevention crucial for safeguarding the doctor's and community's health. The mechanism is fluid film bursting in small airways, and vocal cord vibration explains aerosol emission from the respiratory tract.

What Are the Types of Aerosols and Ill Effects?

1. Therapeutic Aerosols: Intended to treat. Nebulizers included.

2. Exhaled Aerosols: Normal breathing time released onto air contains secretions and infectious agents. It can help spread respiratory infections.

3. Environmental: Due to humidity, temperature changes, and ventilation issues.

Ill effects include:

• Transmission of Infectious Agents: Infectious agents may be inhaled or spread to other individuals and patients.

• Environmental Effect: Aerosols have more air time than other particles; they can settle on surfaces and can be transported when an individual touches the surface and then touches his face,

• Allergic Reactions: These minute particles can cause numerous allergies that cannot be assessed or treated at that level. Aerosols can penetrate deep and cause inflammatory reactions.

Aerosols can be monitored using fluorescent tracers and sampling from the types of equipment worn by healthcare workers. Indirect monitoring includes assessing the room's temperature, humidity, and moisture before and after the procedure. Particle sizing and scattering instruments are used in research studies to check the concentration of aerosol generation.

What Are the Aerosol-Generating Non-invasive Support Systems?

Non-invasive Ventilation System: It is used to maintain open airways.

1. Continuous Positive Airway Pressure: This procedure uses less aerosol than other procedures. It delivers constant pressure levels throughout the respiratory cycle, preventing airway collapse. It is commonly utilized in respiratory failure cases.

2. Bilevel Pressure Positive Pressure: Increased coughing is seen with increased particles. It delivers pressure at two different levels: inspiratory and expiratory. This helps in both inhalation and exhalation. This is used in exacerbations of chronic obstructive pulmonary disease.

Humidification: Used to prevent drying. Humidification systems also incorporate air and release water droplets.

High-Flow Nasal Cannula Therapy: Delivers hot and humid air through a cannula in the nose, aiding respiration and providing oxygen. Used post-extubation patients and conditions requiring oxygen therapy.

Nebulizer Therapy: This treatment involves delivering certain medications directly inside the airways. The mechanism involves converting the liquid medicine into a mist, which is easy to inhale. It is used in asthma, chronic bronchitis, and cystic fibrosis. Although it is very beneficial, it generates aerosol in large amounts.

Cough Assist Devices: These devices help patients with cough by applying positive pressure to help them inhale and exhale. They are mainly used in patients with neuromuscular disorders and conditions that make clearing secretions difficult.

How to Mitigate This Risk?

1. Ensure proper mask fitting and usage. When any equipment is an issue, care must be taken to ensure it is of adequate size and completely covers the nose and mouth area.

2. Assessment of the types of equipment regularly to evaluate any leaks. Regular monitoring and servicing should be performed so that minimum to no leaks are involved.

3. Adequate ventilation in the setup is required to minimize aerosols. An adequate ventilation system helps disperse particles and dilute the concentration of aerosols.

4. Using closed systems with filters to disperse aerosols helps mitigate the spread of aerosols that remain in closed areas that have been left aside for some time.

5. Future research should focus on developing precise aerosol monitoring techniques using recent technological advances. Adding real-time imaging to visualize what is happening in the particle world helps to understand and present a solution.

6. Patients must be treated with a personalized approach based on their current health condition and applicable treatment.

7. Integrating nanotechnology with the treatment modes and incorporating antiviral or antibacterial medications will help decrease the infection to a larger level.

What Are the Precautions for Healthcare Workers?

Recommendations and guidelines for aerosol management have evolved.

1. Healthcare workers must wear all protective equipment. Respirators, masks, gloves, gowns, eyewear, and headgear must be employed.

2. Proper training on the use of equipment and infection control.

3. Properly trained individuals should demonstrate the usage of devices in a way that minimizes exposure. Also, infection control and ways to disperse the aerosol should be studied.

4. Devices must be selected based on those with minimum aerosol generation.

5. Regular training and drills should be conducted.

6. Collaborate with the public health department to provide the best available care to the public.

7. All healthcare providers must be updated about the latest guidelines issued by the health authorities.

Conclusion

Respiratory support modes like high-flow nasal oxygen and non-invasive ventilation are used. They are aerosol-generating. Only a few studies have been performed as it is complex, randomizing critically ill patients and difficult for healthcare workers. Still, care must be taken to ensure the best treatment with the least aerosol contamination for the healthcare worker and the patient. A balance must be met between patient care and reducing infection risk by aerosol. Education, regular training and evaluation, and ensuring the best devices and care help reach this goal.