News | September 7, 1999

I.V. Q & A: I.V. Access for Obese Patients

Editor's Note: Have questions about infusion therapy? I.V. Q and A is the place to look for answers. Check back weekly for a new question related to the placement, use, and maintenance of I.V.s.

Short of blind sticks, what's the best method of obtaining large-bore I.V. access in mildly and morbidly obese patients?

These patients present an opportunity to reaffirm the competency and skills of the clinically expert clinician.

Have the patient recline comfortably with the extremity that's intended for cannulation positioned and abducted from his side. Apply moist heat to the extremity to relax the patient and enhance peripheral vascular dilation.

As you assess the patient's entire extremity, place the tourniquet about 3 to 4 inches proximal to the antecubital fossa. Encourage him to slowly but strongly open and close his hand. This will give you an opportunity to palpate while observing for venous filling within a very short period of time. Remember, tourniquet time is still important and you don't want to impinge on arterial circulation or nerve function. Working your way from the extremity's distal areas to the proximal region will give you the opportunity to effectively assess your patient's peripheral venous access.

You can palpate many "good" veins in this manner. Remember that you, as the clinician, must know your anatomic landmarks and where the vein pathways should be located.

Reprinted with permission from the INS Newsline, Intravenous Nurses Society, Cambridge, MA; These questions come from I.V. clinicians and are answered by Debbie Benvenuto, CRNI, INS Nurse Educator/IV Therapy and coordinator of the INS National IV Nursing Network.

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