ATS Pulmonary Function Laboratory Manual

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

flux that can artificially elevate Po 2 results. Therefore, it is strongly recommended that specimens obtained in plastic syringes for blood gas measurements be stored at room temperature. If analysis is anticipated to be delayed by more than 30 minutes, the blood should be collected in a glass syringe and placed in an ice water bath (1, 2). Proper specimen labeling is critical to assuring appropriate interpretation of results and adhering to good labo- ratory practice standards. The key components of proper documentation are: patient’s name, identification number, location, body temperature, respiratory rate, date, time of sampling, sampling site, results of a modified Allen test, name or initials of person who obtained the specimen, name of physician requesting the test, and any therapeutic interventions (e.g., mechanical ventilation settings, supplemental O 2 flow rate, and delivery system) (1). The American Association for Respiratory Care and the Clinical and Laboratory Standards Institute have published guidelines for percutaneous arterial blood sampling. This procedure includes the most recent recommendations (1, 3). A list of relative contraindications is presented in Table 15.2. Equipment and Supplies All equipment should be used in accordance with the manufacturer’s instructions. The following equipment is required to collect an arterial blood specimen: 1. Collection Device 1.1. For percutaneous arterial blood sampling a 1-, 3-, or 5-ml, self-filling, plastic, disposable syringe, prefilled with an appropriate amount and type of lyophilized heparin salt or other suitable coagu- lant, is most common (1, 2). 1.2. Follow manufacturer recommendations for use of different types of syringes (e.g., pre-set or self- filling syringes, and aspiration-type syringes). 2. Hypodermic needles Indications and Contraindications Indications for arterial blood sampling are provided in Table 15.1.

Table 15.1

Indications for Arterial Blood Sampling (3)

Clinical Indications for arterial blood sampling: • Evaluation of adequacy of ventilation, acid–base status, oxygenation status, and the O 2 • Quantification of the patient’s response to therapeutic intervention and/or diagnostic evaluation • Monitor the severity and progression of a documented disease process

-carrying capacity of blood

Table 15.2

Relative Contraindications for Performing Arterial Blood Sampling (2)

Relative contraindications for arterial blood sampling include: • A negative Allen test for a radial puncture site ( see Patient Preparation, section 7) • Performance of a puncture through a lesion or through or distal to a surgical shunt • Coagulapathy or medium-to-high-dose anticoagulation therapy (relative)

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