Perioperative Pulmonary Assessment
SpO₂ is low. PaCO₂ is elevated. The patient has pneumonia. How far should you go? Perioperative pulmonary assessment is four separate questions — risk, oxygenation, ventilation, and pneumonia severity. Each demands a different tool.
Select a Tool
ARISCAT
Put a number on PPC risk — and know what to do with it
When to use
- •Replace a gut feeling with evidence-based stratification
- •Identify high-risk patients before surgery, not after
Main inputs
Returns
- •Risk class (low / intermediate / high)
- •3-phase management plan (pre / intra / postop)
- •Clinical reasoning map
Preoperative Oxygenation
Is this SpO₂ or PaO₂ acceptable for the patient's age?
When to use
- •SpO₂ is borderline — age-appropriate or a real concern?
- •Checking whether PaO₂ warrants further workup
- •Deciding whether an ABG is clinically indicated
Main inputs
Returns
- •Expected PaO₂
- •Oxygenation status
- •Clinical interpretation
Wells Score for PE
Stratify pre-test PE probability before ordering D-dimer or CTPA
When to use
- •Suspected PE — can D-dimer rule it out, or does this patient need CTPA?
- •Deciding whether to image: stratify pre-test probability before ordering
Main inputs
Returns
- •Wells score with pre-test PE probability
- •Risk category (low / moderate / high)
- •D-dimer vs CTPA recommendation
Room Air ABG
Read ABG values through the lens of perioperative risk
When to use
- •PaCO₂ is elevated — acute, chronic, or compensation?
- •HCO₃⁻ is high — respiratory compensation or metabolic?
- •Assessing hypoventilation risk before surgery
Main inputs
Returns
- •Oxygenation assessment
- •Ventilation assessment
- •Compensation pattern
- •Perioperative concern
CURB-65 Pneumonia Severity
Estimate severity and decide — outpatient, admit, or escalate urgently?
When to use
- •Suspected or confirmed community-acquired pneumonia — how sick is this patient?
- •Deciding outpatient vs inpatient before or instead of surgery
- •Borderline case — is this pneumonia serious enough to escalate care now?
Main inputs
Returns
- •CURB-65 score (0–5)
- •Severity category with approximate 30-day mortality
- •Disposition and management direction
PONV Risk & Management
Stratify PONV risk and select multi-mechanism prophylaxis before surgery
When to use
- •Pre-op planning — does this patient need PONV prophylaxis, and how many agents?
- •PONV occurred despite prophylaxis — what rescue agent avoids the same class?
Main inputs
Returns
- •Apfel score (0–4) with incidence estimate
- •Risk category (low / moderate / high)
- •Multi-drug prophylaxis strategy
- •Rescue therapy guidance
Which tool for this patient?
- Need a PPC risk estimate before surgeryARISCAT
- SpO₂ is borderline — age-appropriate or a problem?Oxygenation
- Should I get an ABG?Oxygenation
- Suspected PE — D-dimer or CTPA?Wells Score
- PaCO₂ is elevated — chronic CO₂ retainer?Room Air ABG
- HCO₃⁻ is high — compensation or metabolic?Room Air ABG
- Suspected pneumonia — outpatient or admit?CURB-65
- Pneumonia before surgery — how aggressive should workup be?CURB-65
- High-risk patient — how many antiemetic agents do they need?PONV