Literature ReviewZeroing a Transducer on an External Ventricular DrainMalloy, Rachel Author Information Questions or comments about this article may be directed to Rachel Malloy, MSN RN CNRN SCRN, at [email protected] or [email protected]. R.M. is Clinical Application Manager, Natus. The author is a full-time employee of Natus, a company that manufactures and sells intracranial pressure monitor devices, including external ventricular drains. She owns Integra stock, a company that manufactures and sells intracranial pressure monitor devices, including external ventricular drains. Journal of Neuroscience Nursing 55(2):p 54-59, April 2023. | DOI: 10.1097/JNN.0000000000000691 Buy Metrics Abstract BACKGROUND: External ventricular drains (EVDs) are commonly used in severely brain-injured patients to diagnose intracranial hypertension. The accuracy of the intracranial pressure reading is dependent on zeroing the external transducer to air. Recent concern about zeroing techniques has been identified in the neuroscience community. The open method requires removing the nonvented cap, and the closed method requires zeroing through the filter at the top of the burette. This critical appraisal seeks to explore whether zeroing a transducer on an EVD through the filter of the burette provides the same baseline zero as opening the transducer to air. METHODS: Independent searches in CINAHL, PubMed, and Web of Science were conducted using “external ventricular drain* OR EVD AND transducer”; secondary search terms included “zero AND transducer” AND “ventric.” RESULTS: Database search produced 1 single observation study and 2 clinical practice guidelines from neuroscience professional organizations. The single observation study provided no evidence of equivalence between the 2 zeroing methods; the 2 clinical practice guidelines reference the open method. The transducer manufacturer's instructions for use direct the clinician to open the transducer to air by removing the nonvented cap. CONCLUSION: The question “Does zeroing the transducer on an EVD through the filter of the burette provide the same baseline zero as opening the transducer to air?” cannot be answered with the results of this appraisal. However, evidence found in the literature does suggest an open method to ensure the most accurate physiological value for treatment decisions. Copyright © 2023 American Association of Neuroscience Nurses