Clinical Pulmonary Infection Score (CPIS) for Ventilator-Associated Pneumonia (VAP)

CPIS Calculator — Clinical Pulmonary Infection Score

VAP / HAP diagnosis & severity · Modified CPIS · IDSA/ATS HAP/VAP Guidelines 2023

⚠ ICU · HAP/VAP

CPIS = sum of 6 clinical variables, each scored 0–2 · Maximum score 12 points · Threshold ≥ 6 suggests VAP/HAP

Validated for mechanically ventilated ICU patients ≥ 48 hours · Modified CPIS adds microbiological culture results · Score recalculated at 72 hr

IDSA/ATS 2023 does not recommend CPIS alone for initiating antibiotics — use alongside clinical judgment, cultures, and imaging · See FAQ

Please complete all six parameters.

Six CPIS parameters — select each observed finding

1. Temperature (°C)

Core or tympanic temperature · Fever or hypothermia both score

0 pts

36.5 – 38.4 °C (Normal) — 0 pts 38.5 – 38.9 °C (Low-grade fever) — 1 pt ≥ 39.0 °C or ≤ 36.0 °C (Fever / Hypothermia) — 2 pts

2. White Blood Cell Count (×10³/mm³)

Leukocytosis or leukopenia · Add 1 pt for band forms ≥ 500 cells/mm³

0 pts

4.0 – 11.0 ×10³/mm³ (Normal) — 0 pts < 4.0 or > 11.0 ×10³/mm³ (Abnormal) — 1 pt < 4.0 or > 11.0 + Band forms ≥ 500 — 2 pts

3. Tracheal secretions (suction episodes / 8 hr)

Quantity and purulence of tracheal aspirate · Purulent = yellow/green/brown

0 pts

Absent or < 14 suctionings — 0 pts ≥ 14 suctionings (non-purulent) — 1 pt ≥ 14 suctionings + Purulent secretions — 2 pts

4. Oxygenation — PaO₂ / FiO₂ (mmHg)

Calculated from ABG · ARDS requires bilateral CXR infiltrates + non-cardiogenic

0 pts

P/F > 240 mmHg or ARDS present — 0 pts P/F ≤ 240 mmHg and no ARDS — 2 pts

5. Chest radiograph (CXR / CT) findings

New or progressive infiltrate · CT is superior for differentiating from heart failure / atelectasis

0 pts

No infiltrate — 0 pts Diffuse or patchy bilateral infiltrate — 1 pt Localised / segmental infiltrate — 2 pts

6. Tracheal aspirate culture (modified CPIS)

Semiquantitative BAL (≥ 10⁴ CFU/mL) or tracheal aspirate · Gram stain adds to score

0 pts

No growth or ≤ 1+ pathogenic bacteria — 0 pts Pathogenic bacteria > 1+ — 1 pt Pathogenic bacteria > 1+ AND same organism on Gram stain > 1+ — 2 pts

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CPIS — VAP / HAP Probability

Low probability of VAP/HAP

Score 0 — threshold < 6

Reassess if clinical deterioration; antibiotics should be guided by cultures not CPIS alone.

CPIS 0 / 12 · Low risk

CPIS score interpretation — IDSA/ATS 2023 context

Score	VAP/HAP probability	Clinical guidance	ICU mortality
0 – 2	Very low	Low clinical suspicion · Continue monitoring · Do not initiate antibiotics on score alone	~10–15%
3 – 5	Moderate	Obtain BAL/mini-BAL cultures; chest CT if CXR equivocal · Antibiotics only if clinical deterioration	~20–30%
6 – 8	High (threshold met)	VAP/HAP likely · Initiate empirical antibiotics per IDSA/ATS 2023; deescalate based on culture day 3	~30–40%
9 – 12	Very high	Severe VAP · Broad-spectrum including MRSA/Pseudomonas coverage · ICU escalation · Urgent ID/pulmonology consultation	~50–65%

CPIS threshold ≥ 6 = VAP/HAP suspected · Modified CPIS adds culture result · Score ≥ 6 at 72 hr = poor prognosis · IDSA/ATS 2023: do not use CPIS alone to start/stop antibiotics · No patient data stored

Clinical references

• 1.Pugin J, Auckenthaler R, Mili N, et al. Diagnosis of ventilator-associated pneumonia by bacteriologic analysis of bronchoscopic and nonbronchoscopic blind bronchoalveolar lavage fluid. Am Rev Respir Dis. 1991;143(5):1121–1129. doi:10.1164/ajrccm/143.5_Pt_1.1121 (Original CPIS derivation)
• 2.Fartoukh M, Maître B, Honoré S, et al. Diagnosing pneumonia during mechanical ventilation: the clinical pulmonary infection score revisited. Am J Respir Crit Care Med. 2003;168(2):173–179. doi:10.1164/rccm.200212-1449OC (Modified CPIS + culture)
• 3.Kalil AC, Metersky ML, Klompas M, et al. Management of Adults With Hospital-acquired and Ventilator-associated Pneumonia: 2016 Clinical Practice Guidelines by the IDSA and the ATS. Clin Infect Dis. 2016;63(5):e61–e111. doi:10.1093/cid/ciw353
• 4.IDSA/ATS HAP/VAP Guidelines Update 2023. Updated recommendations on antibiotic stewardship, de-escalation, and biomarker-guided therapy (procalcitonin). Clin Infect Dis. 2023 (forthcoming updates).
• 5.Schurink CA, Van Nieuwenhoven CA, Jacobs JA, et al. Clinical pulmonary infection score for ventilator-associated pneumonia: accuracy and inter-observer variability. Intensive Care Med. 2004;30(2):217–224. doi:10.1007/s00134-003-2073-2 (CPIS inter-observer variability)
• 6.Singh N, Rogers P, Atwood CW, et al. Short-course empiric antibiotic therapy for patients with pulmonary infiltrates in the intensive care unit. A proposed solution for indiscriminate antibiotic prescription. Am J Respir Crit Care Med. 2000;162(2):505–511. doi:10.1164/ajrccm.162.2.9909095 (CPIS-guided antibiotic stewardship)
• 7.Torres A, Niederman MS, Chastre J, et al. International ERS/ESICM/ESCMID/ALAT guidelines for the management of hospital-acquired pneumonia and ventilator-associated pneumonia. Eur Respir J. 2017;50(3):1700582. doi:10.1183/13993003.00582-2017
• 8.Klompas M, Branson R, Cawcutt K, et al. Strategies to prevent ventilator-associated pneumonia, ventilator-associated events, and nonventilator hospital-acquired pneumonia in acute care hospitals: 2022 Update. Infect Control Hosp Epidemiol. 2022;43(6):687–713. doi:10.1017/ice.2022.88
• 9.Hellyer TP, Ewan V, Wilson P, Simpson AJ. The Intensive Care Society recommended bundle of interventions for the prevention of ventilator-associated pneumonia. J Intensive Care Soc. 2016;17(3):238–243. doi:10.1177/1751143716644461

Frequently asked questions

Medical disclaimer

For qualified ICU and infectious disease professionals only. The CPIS Calculator is an educational decision-support tool. It is not a substitute for clinical judgment, microbiological culture results, respiratory specimen analysis, chest imaging review, or institutional antimicrobial stewardship protocols.

The CPIS was originally derived from a small single-centre cohort (Pugin et al., 1991) and has significant limitations including poor inter-observer reliability (κ = 0.35–0.50) and variable diagnostic accuracy across populations. The IDSA/ATS 2023 HAP/VAP guidelines do not recommend using CPIS alone as the criterion to initiate or discontinue antibiotics — it should be one component of a comprehensive clinical assessment.

Diagnostic accuracy: CPIS ≥ 6 has sensitivity ~65–77% and specificity ~42–85% for VAP, depending on the reference standard used (BAL quantitative culture vs autopsy). A negative CPIS (< 6) does not exclude VAP. The modified CPIS (adding culture results on day 3) has improved specificity for antibiotic stewardship decisions.

Antibiotic selection must be guided by local antimicrobial resistance patterns (MRSA prevalence, Pseudomonas risk factors per IDSA/ATS 2023 criteria), prior culture history, allergy status, renal function, and infection control considerations. This tool does not provide antibiotic recommendations.

This tool does not store, transmit, or process patient-identifiable information. All calculations occur locally in the user's browser.

Last reviewed: January 2026 · Pugin 1991 · Fartoukh Modified CPIS 2003 · IDSA/ATS HAP/VAP 2016/2023 · ERS/ESICM/ESCMID 2017 · SHEA 2022 VAP prevention bundle