Inhalation

Introduction to Inhalation Therapy

Inhalation therapy delivers medication directly into the respiratory tract as a mist, aerosol, or fine powder. Because the lungs possess a massive surface area and a rich network of blood capillaries, drugs given this way enter the bloodstream very rapidly. This route also allows smaller doses to target the airways directly, which minimizes unwanted side effects in the rest of the body compared to tablets or injections. Midwives frequently use this method to manage acute bronchospasm, chronic asthma, and other respiratory complications during pregnancy and the postnatal period.

Respiratory Tract Anatomy and Drug Deposition

Getting a drug to the right part of the airway depends heavily on particle size and breathing technique. The upper respiratory tract filters out large, heavy particles, preventing them from reaching the lungs. Midwives must understand that particles between 1 and 5 micrometers are ideal because they travel deeper into the bronchioles and alveoli. Larger particles usually get trapped in the mouth and throat, leading to localized side effects like oral thrush with corticosteroid inhalers.

Types of Inhalation Devices

Various devices deliver aerosolized medications, each requiring a specific technique from the patient.

• Metered-Dose Inhaler (MDI): Delivers a specific amount of medicine using a propellant gas, often best used with a spacer.
• Dry Powder Inhaler (DPI): Relies entirely on the patient's fast, deep breath to draw the medication powder out of the device without any gas propellant.
• Nebulizer: Uses compressed air or oxygen to turn liquid medication into a continuous mist that the patient breathes in through a mask or mouthpiece.

Step-by-Step Administration Technique

Proper administration ensures maximum drug delivery to the target tissues.

1. Preparation: Check the drug chart, inspect the expiry date, and shake the MDI canister well.
2. Exhalation: Instruct the patient to breathe out completely, emptying their lungs of normal air.
3. Actuation: Place the mouthpiece in the mouth, seal the lips tightly around it, and press down once on the canister while starting a slow, deep breath in.
4. Breath-hold: Remove the device and ask the patient to hold their breath for 10 seconds, or as long as comfortably possible, before breathing out slowly.

Patient Education and Common Errors

Many patients struggle with inhaler technique, which leads to poor symptom control. Common mistakes include coordinating the hand press with the breath too late, inhaling too quickly, or forgetting to rinse the mouth after using a steroid inhaler. Midwives play a crucial role by observing the patient demonstrate technique using a placebo device, correcting errors gently, and emphasizing the importance of mouth hygiene to prevent fungal infections.

Nursing Responsibilities and Safety Monitoring

Administering inhaled medications safely requires ongoing clinical observation. Midwives must monitor the patient's respiratory rate, oxygen saturation, and breath sounds before and after treatment to assess effectiveness. If the drug is a beta-agonist bronchodilator, the midwife should watch for predictable systemic side effects like mild tremors or tachycardia. Documenting the response accurately ensures continuity of care and helps the medical team adjust treatment plans when breathing does not improve.