ATS Pulmonary Function Laboratory Manual

ATS Pulmonary Function Laboratory Management & Procedure Manual | 3rd Edition

Table 11.2

Contraindications for Performing Maximum Respiratory Pressures

Absolute Contraindications

• Unstable angina • Recent myocardial infarction (within the previous 4 weeks) or myocarditis • Recent pneumothorax

• Uncontrolled systemic hypertension • Lung biopsy within previous week

Relative Contraindications

• Resting diastolic blood pressure >110 mm Hg or resting systolic blood pressure >200 mm Hg • Recent spinal injury • Recent eye surgery • Non-compliant patient or one who is not capable of performing the test because of weakness, pain, fever, dyspnea, lack of coordination, or psychosis.

Contraindications for performing maximum respiratory pressures are provided in Table 11.2.

Equipment and Supplies 1.

Several equipment options are commercially available. Equipment can also be fabricated in the laboratory with parts available from several sources. System description (e.g., manufacturer, model, type, accessories, additional features, and software version) should be included here. An example of a device is provided below. 1.1. Portable handheld system with two diaphragm gauges connected to a large-bore metal “T” or “Y” valve. The gauges, scaled in cm H 2 O, attach to a pressure tap in the distal end of the cylinder with rigid plastic tubing: one gauge records positive pressure; the other gauge records negative pressure. The distal end of the unit is closed, except for a small opening (a “controlled leak” 1 to 2 mm inside diameter, 15 mm long). The purpose of the small opening is to help prevent glottic closure and to prevent facial muscles from producing significant additional pressures (1, 3). 2. Disposable/reusable supplies: flanged mouthpiece, nose clip, and other miscellaneous equipment or supplies.

Patient Preparation (Pre-Test Instructions) 1. The patient should refrain from heavy exercise immediately before testing. 2. The effect of smoking is unclear, but ask the patient if he/she has recently smoked. 3. Explain and demonstrate the procedure.

Assessment of Patients 1.

Assess each patient for physical and developmental status to determine ability to undergo the diagnostic test(s) and if special arrangements are required. If there is a language barrier, an interpreter will be used. 2. Ask each patient if he/she has complied with the preparation criteria, including: 2.1. If they have recently smoked, and if so, when. 2.2. The time of his/her last meal. 2.3. The last time he/she took medications for the lungs, and what types.

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