From the Guidelines
A complete blood count (CBC) should be sent within 24-48 hours before performing bronchoscopy with transbronchial biopsies, as it helps assess platelet count, hemoglobin levels, and leukocyte count to minimize bleeding risk and identify pre-existing conditions that may complicate the procedure. The primary purpose of the CBC is to evaluate the patient's hematologic status, particularly the platelet count, which should ideally be above 50,000/μL to minimize bleeding risk during the procedure 1. Patients with thrombocytopenia (low platelets) may require platelet transfusion before proceeding. Additionally, the CBC helps evaluate hemoglobin levels to identify pre-existing anemia, which could complicate management if significant bleeding occurs during the procedure. Leukocyte count and differential can also provide information about ongoing infection or inflammation that might affect procedural decisions.
For patients on anticoagulants or antiplatelet medications, CBC testing should be coordinated with appropriate medication holds (typically 5-7 days for aspirin/clopidogrel, or according to the specific anticoagulant's pharmacokinetics) 1. This timing allows for intervention if abnormalities are detected while still being recent enough to reflect the patient's current hematologic status at the time of the procedure. Coagulation studies (PT/INR, PTT) should also be checked alongside the CBC in patients with suspected coagulopathy or those on anticoagulant therapy 1. It is essential to note that routine preoperative checks of the platelet count and/or prothrombin time are only required in those patients with known risk factors having routine bronchoscopy without transbronchial biopsy 1.
Some key points to consider when evaluating the need for a CBC before bronchoscopy with transbronchial biopsies include:
- Platelet count: ideally above 50,000/μL to minimize bleeding risk
- Hemoglobin levels: to identify pre-existing anemia
- Leukocyte count and differential: to provide information about ongoing infection or inflammation
- Coagulation studies (PT/INR, PTT): to evaluate patients with suspected coagulopathy or those on anticoagulant therapy
- Medication holds: coordinate CBC testing with appropriate medication holds for patients on anticoagulants or antiplatelet medications.
From the Research
Pre-Bronchoscopy Evaluation
When considering a bronchoscopy with transbronchial biopsies, it is essential to evaluate the patient's bleeding risk. The following factors should be taken into account:
- Platelet count: A study published in the Journal of bronchology & interventional pulmonology 2 found that bronchoscopy with lavage can be safely performed without platelet transfusion in patients with platelets ≥10 K/μL.
- Coagulation tests: Research published in The European respiratory journal 3 showed that coagulation tests, such as prothrombin time (PT) and activated partial thromboplastin time (aPTT), do not predict bleeding tendency in patients undergoing transbronchial biopsies.
- Medications: A study in Chest 4 found that clopidogrel use significantly increases the risk of bleeding after transbronchial lung biopsy, and it is recommended to discontinue clopidogrel before the procedure.
Timing of CBC
Based on the available evidence, it is recommended to perform a complete blood count (CBC) before bronchoscopy with transbronchial biopsies to assess the patient's platelet count and other bleeding risk factors. The timing of the CBC is not explicitly stated in the provided studies, but it is generally recommended to perform the test close to the time of the procedure to ensure that the results are accurate and up-to-date.
Key Considerations
Some key considerations when evaluating a patient's bleeding risk before bronchoscopy with transbronchial biopsies include: