Respiratory Concerns

Core Concepts

Oxygenation versus ventilation

The two jobs of the lungs are distinct, and critical care demands you keep them separate:

• Oxygenation — getting oxygen from the air into the blood at the alveoli (the tiny air sacs where gas exchange happens). It is tracked by pulse oximetry and by oxygen levels in arterial blood.
• Ventilation — moving air in and out, which is how carbon dioxide gets exhaled. It is tracked by carbon dioxide levels.

You can have one without the other. A patient can be pink — well oxygenated — while breathing too shallowly to clear carbon dioxide (ventilation failure). Another can be blue — severely hypoxic — while blowing off carbon dioxide perfectly. SpO₂ measures oxygenation only; it says nothing about carbon dioxide. This single distinction unlocks the rest of the topic.

Recognizing respiratory distress

Respiratory distress is a clinical picture, not one number:

• Rate and depth: fast, shallow breathing moves little air; a falling rate with rising carbon dioxide is late and dangerous.
• Work of breathing: accessory muscle use (neck, shoulders, between the ribs), nasal flaring, retractions, or paradoxical chest-abdomen movement — the body is struggling.
• Speech: a patient who cannot speak in full sentences is in serious trouble.
• Lung sounds: crackles (fluid or collapsed airways), wheezes (narrowed airways), diminished sounds (little air moving).
• Mental status: confusion or lethargy can mean hypoxia or rising carbon dioxide — the brain complains first.
• Position: patients in distress sit up or lean forward (tripod position) to recruit every breathing muscle.

Oxygen therapy

Oxygen is a drug: it is prescribed, delivered by specific devices, monitored for effect, and handled with fire safety. Devices differ mainly in how much oxygen they can deliver:

• Nasal cannula — small prongs in the nares; comfortable, allows talking and eating, low-flow.
• Simple face mask — covers the nose and mouth; higher concentrations than a cannula.
• Non-rebreather mask — a mask with a reservoir bag that delivers high concentrations for significant hypoxia.
• High-flow systems — warmed, humidified oxygen at high rates.

Nursing details matter: check nares and skin behind the ears for breakdown, and follow fire-safety rules (no smoking or open flames near oxygen). Flow rates and device choice are provider orders — the nurse sets up, monitors, and documents response.

Noninvasive ventilation (NIPPV)

When oxygen alone is not enough but the patient can still protect their airway, noninvasive ventilation — commonly CPAP (continuous positive airway pressure) or BiPAP (two pressure levels) — delivers positive pressure through a sealed mask. The pressure splints the airways open, recruits collapsed alveoli, and reduces the work of breathing, buying time for treatment (like bronchodilators or diuretics) to work.

Nursing care: a good mask seal without excessive pressure, skin protection on the nose and face, watching for leaks, and — most importantly — monitoring for improvement. If the patient tires, desaturates, or becomes less responsive, the therapy is failing and escalation (often intubation) is needed. NIPPV is a bridge, not a destination.

Mechanical ventilation and the artificial airway

When the patient cannot maintain gas exchange, cannot protect the airway, or is too exhausted to keep breathing, they are intubated — an endotracheal tube placed through the mouth into the trachea, connected to a ventilator that delivers breaths (long-term, the tube may be replaced by a tracheostomy). A cuff on the tube seals the airway.

Ventilator basics the nurse must understand:

• The machine delivers breaths with settings for oxygen concentration, breath size, and rate; modes differ in how much work the patient does (full support versus breathing with help).
• PEEP (positive end-expiratory pressure) keeps alveoli open at the end of each breath, improving oxygenation in stiff lungs.
• Alarms are messages. A high-pressure alarm means resistance to flow: coughing, secretions in the tube, the patient biting the tube, a kinked circuit, or the patient fighting the ventilator. A low-pressure alarm means a leak or disconnection — the patient may not be getting breaths at all. The nurse never silences an alarm and walks away.
• Tube security is life safety: the tube is secured at a marked depth at the lips, and its position is verified and documented.

Nursing care of the ventilated patient: suctioning per protocol (preoxygenation, aseptic technique, limited duration, watching the patient throughout), oral care (the mouth is a reservoir for infection), cuff pressure and head-of-bed checks per protocol, skin care around the tube, and — because the patient cannot speak — alternative communication (writing, boards, gestures) and attention to comfort and sedation per orders.

ARDS and pulmonary edema: lungs that fill with fluid

Two common critical-care lung problems share a final picture — fluid in the lungs — with different causes:

• Acute respiratory distress syndrome (ARDS): a severe inflammatory lung injury (from sepsis, pneumonia, trauma, pancreatitis, and other triggers) that makes the alveoli leak fluid. The lungs become stiff, oxygenation plummets, and the patient needs aggressive ventilator support — including, in severe cases, proning (face-down positioning) to improve blood-flow matching, per institutional protocols.
• Cardiogenic pulmonary edema: the heart fails and blood backs up into the lungs. The history and exam (heart disease, crackles, edema, weight gain) help tell it apart from ARDS.

Both present with dyspnea, crackles, and hypoxia; both demand the nurse watch oxygenation, work of breathing, and response to treatment.

Preventing ventilator-associated complications

The ventilator saves lives and creates risks, and prevention is nursing work:

• Ventilator-associated pneumonia (VAP): prevented with head-of-bed elevation, regular oral care, cuff pressure management, hand hygiene, and minimizing time on the ventilator (per protocol).
• Skin breakdown: from tubes, masks, and immobility — turn and reposition, protect pressure points.
• Weakness and delirium: from sedation and immobility — sedation is minimized per protocol, and early mobility gets the patient moving as soon as it is safe.

Every facility has its own bundles and protocols; the nurse's job is to know them and deliver them consistently. Person-first language applies throughout: the team cares for a person who is intubated, not "the vent."

Common Confusions