We assign code 94375 (respiratory flow volume loop) when a preoperative evaluation is ordered to distinguish between fixed and variable upper-airway obstructions. Can you provide any billing guideline we should know?


The flow volume loop is considered an alternate method of calculating a standard spirometric parameter. Alternate methods of reporting identical or duplicative data should not be billed separately on the same date of service (DOS).

Unit of service edits do exist for 94375. Specifically, when multiple determinations are performed on the same DOS to complete a pulmonary assessment, only one unit of service is appropriate. The American Medical Association (AMA) states that 94375 should not be reported in conjunction with the following:

94010 Spirometry, including graphic record, total and timed vital capacity, expiratory flow rate measurement(s), with or without maximal voluntary ventilation
94060 Bronchodilation responsiveness, spirometry as in 94010, pre- and post-bronchodilator administration
94728 Airway resistance by impulse oscillometry


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