Clinical
P/F Ratio: Formula, Normal Range & ARDS Chart
Calculate the P/F ratio from PaO₂ and FiO₂, review expected values, and interpret Berlin ARDS oxygenation thresholds with worked examples.
8 min readRead article
Respiratory education
The PulmTools Blog
Clear, practical guides for the decisions behind respiratory care. Explore blood gases, oxygenation, ventilation, and more.
Guides for clinicians, respiratory therapists, and students.
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A clearer way to read an ABG.
A step-by-step foundation for interpreting arterial blood gases and connecting the numbers to the patient in front of you.
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Explore recent thinking and practical clinical guides.
Clinical
COPD Oxygen Saturation Target: When to Use 88–92%
Learn when the 88–92% oxygen target applies during a COPD exacerbation, what NICE and BTS guidance says, and when blood gas results should change the plan.
11 min readRead article
Clinical
Nebulized Hypertonic Saline: Uses, Dosing & Safety
Compare 3% and 7% nebulized hypertonic saline, review bronchiectasis and cystic fibrosis guidance, and learn dosing examples, airway-clearance sequencing, and bronchospasm precautions.
12 min readRead article
Clinical
Pulmonary Embolism Symptoms and Clinical Clues: Dyspnea, Chest Pain, and PE Signs
Learn common pulmonary embolism symptoms and clinical clues including dyspnea, pleuritic chest pain, tachycardia, hemoptysis, syncope, hypoxemia, unilateral leg swelling, and when to start formal PE evaluation.
8 min readRead article
Clinical
D-Dimer False Positives: Causes, Clinical Interpretation, and PE Evaluation
Learn common causes of false positive D-dimer including infection, inflammation, cancer, pregnancy, age, surgery, trauma, hospitalization, and how to interpret elevated D-dimer in pulmonary embolism workups.
8 min readRead article
Clinical
PE Rule-Out Pathway for Low-Risk Patients: PERC, D-Dimer, and Imaging Guide
Learn the practical pulmonary embolism rule-out pathway for low-risk patients using Wells Score, PERC, D-dimer, age-adjusted D-dimer, and imaging decisions to avoid unnecessary CT when PE can be safely excluded.
8 min readRead article
Clinical
PE Likely vs PE Unlikely: Wells Score Two-Tier Interpretation Guide
Learn how to interpret the Wells Score using the PE Likely (>4) and PE Unlikely (≤4) two-tier model, including D-dimer use, imaging decisions, differences from the older three-tier system, and modern pulmonary embolism pathways.
8 min readRead article
Clinical
CTPA vs V/Q Scan for Pulmonary Embolism: Imaging Choice, Contrast Risk, and Pregnancy Considerations
Compare CT pulmonary angiography and V/Q scanning for pulmonary embolism diagnosis, including contrast allergy, renal dysfunction, pregnancy, chest X-ray findings, radiation tradeoffs, and when each imaging test is preferred.
10 min readRead article
Clinical
YEARS Algorithm for Pulmonary Embolism: Criteria, D-Dimer Thresholds, and Clinical Use
Learn how the YEARS algorithm uses three clinical criteria and adjusted D-dimer thresholds to evaluate suspected pulmonary embolism, safely exclude PE in selected patients, and reduce unnecessary imaging.
10 min readRead article
Clinical
D-Dimer for Pulmonary Embolism: Interpretation, False Positives, and Rule-Out Use
Learn how to interpret D-dimer for suspected pulmonary embolism, including when it helps rule out PE, why false positives happen, how age-adjusted thresholds work, and when imaging is still required.
9 min readRead article
Clinical
Pulmonary Embolism Diagnostic Algorithm: Wells, PERC, D-Dimer & Imaging
Follow a practical pulmonary embolism diagnostic algorithm using Wells Score, PERC, D-dimer, age-adjusted D-dimer, CTPA, V/Q scanning, and high-risk PE cautions.
10 min readRead article
Clinical
Age-Adjusted D-Dimer: Formula, Cutoff, and Pulmonary Embolism Guide
Learn how to calculate the age-adjusted D-dimer cutoff, when to use it for pulmonary embolism evaluation, why it improves specificity in older adults, and how it fits into modern PE diagnostic pathways.
8 min readRead article
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