Perioperative Pulmonary Management
Understanding postoperative pulmonary complications — what to look for, and what can be changed.
Level 1 — Quick Learn
Medical students and junior residents
What is perioperative pulmonary assessment?
The reason for perioperative pulmonary assessment is simple. Some patients develop serious breathing problems after surgery — and most of them show warning signs beforehand.
Postoperative pulmonary complications (PPCs) — pneumonia, atelectasis, respiratory failure, pleural effusion — are among the most common and consequential adverse events after surgery. They can prolong hospital stay, lead to unexpected ICU admission, and worsen outcomes.
This page maps out what to look for and what can be changed. Think of it as the foundation for understanding ARISCAT and other perioperative pulmonary tools.
What are postoperative pulmonary complications (PPCs)?
PPCs cover a range of respiratory problems that develop after surgery. They rarely occur in isolation — each one can trigger or worsen the others.
- Atelectasis — starts early, often within hours, and is the most common trigger of postoperative pneumonia
- Pneumonia — the most outcome-critical PPC, directly linked to increased mortality
- Acute respiratory failure — requires supplemental oxygen, NIV, or re-intubation
- Pleural effusion and bronchospasm — additional contributors in high-risk patients
More common than expected
In the ARISCAT derivation cohort, PPC incidence reached 42% in high-risk patients. This is not a rare complication. Without deliberate assessment and planning, the numbers do not change.
The four pillars of perioperative pulmonary assessment
Perioperative pulmonary assessment becomes clearer when organised into four perspectives.
| Pillar | What to assess | Why it matters |
|---|---|---|
| Patient factors | Age, SpO2, recent infection, anaemia, COPD | Patient-specific risk — some are modifiable before surgery |
| Oxygenation / ventilation | Preoperative SpO2, respiratory reserve | Reflects how much margin the lung has before surgery |
| Surgical insult | Site, duration, urgency | Closer to the diaphragm and longer duration means greater respiratory impact |
| Postoperative care | Analgesia, mobilisation, airway clearance | Targeted management reduces PPC incidence |
Patient risk factors to assess before surgery
The following five patient factors are the most important. The more that are present, the higher the risk.
- Older age (51 years or over) — respiratory muscle strength, cough reflex, and pulmonary reserve all decline with age
- Low preoperative SpO2 (below 96%) — a marker of insufficient respiratory reserve before any surgical stress
- Recent respiratory infection (within 1 month) — airway hyperresponsiveness and secretion burden persist for weeks
- Preoperative anaemia (Hb ≤ 10 g/dL) — reduced oxygen-carrying capacity increases postoperative respiratory workload
- COPD, asthma, or smoking history — pre-existing reduction in pulmonary reserve
Consider delaying elective surgery if there is active infection
A respiratory infection within the past month adds +17 points on ARISCAT — one of the highest-weighted individual factors. For elective procedures, waiting for full recovery (typically 2–4 weeks) is worth considering. Airway reactivity and secretion burden can persist well beyond symptom resolution.