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When frequent arterial blood samples are required and an umbilical arterial catheter cannot be placed or has been removed because of complications.
Intra-arterial blood pressure monitoring.
To measure preductal Pao2 (usually done with pulse oximeter of the right hand or finger if catheterization not necessary). Right upper extremity catheterization must be done for preductal measurement.
Exchange transfusions (for removal of blood only). Used in peripheral vessel exchange transfusion (PVET) when drawing blood from a peripheral artery and infusing through a peripheral vein.
Not for infusion of hyperalimentation, medications, hypertonic or hypotonic solutions, glucose solutions, or blood product administration.
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Safety-engineered catheter over needle access device based on local practices (22 or 24 gauge; 24 gauge preferred for infants <1500 g), arm board (or two tongue blades taped together), adhesive tape, sterile drapes, gloves, povidone-iodine or skin disinfectant, gloves, antiseptic ointment, suture material optional (needle holder, suture scissors, 4–0 or 5–0 silk sutures), 0.5 or 0.25% normal saline flush solution (latter preferred in premature infants, decreases hypernatremia risk) with heparin (0.25–0.50 unit of heparin/1 mL saline), pressure bag (to prevent backflow and keep the line free of clots), connecting tubing, pressure transducer for continuous blood pressure monitoring, optional: fiber optic light for transillumination or a Doppler/real-time ultrasound to locate the artery.
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Two methods are described here using the radial artery, the most common site because of low complication rates. Methods can be adapted to other arteries. Another common site is the posterior tibial artery, as both the radial and posterior tibial arteries have good collateral circulation. Ulnar (to be used only in the absence of previous radial artery puncture attempt) and dorsalis pedis arteries are alternative sites. The temporal, brachial, and femoral arteries are not recommended. Axillary artery cannulation is very difficult and also not recommended. Temporal artery catheterization may have adverse neurologic sequelae. The brachial artery does not have good collateral flow and can have a lot of complications. Lateral or posterior wrist transillumination or Doppler/real-time ultrasound may be helpful in locating the artery in premature infants. Arterial catheterization requires patience.
Locate the artery by palpation, transillumination, or Doppler/real-time ultrasound. Palpation of the artery can be done at the following sites: radial artery (lateral wrist), ulnar artery (medial wrist), posterior tibial artery (posterior to the medial malleolus), and dorsalis pedis artery (on top of the foot). For technique on transillumination, see Chapter 40. Use of real-time ultrasound and color Doppler imaging can identify the artery and help one guide the catheter in the vessel. It can lead to a shorter time required, a higher first attempt success rate, and a decrease in complications.
Verify adequate collateral circulation in the hand using the modified Allen test. (See Chapter 22.) Some recommend doing a Doppler evaluation to verify collateral flow since there can be false positives with the ...