The purpose of this study is to compare success rates of antegrade and retrograde intravenous (IV) catheters in their ability to aspirate 20 milliliter blood sample within a 2 minute time frame, 3 hours after initial insertion. Antegrade IV catheters are placed identically to conventional IV catheters, with the end of the catheter pointed toward the direction of blood flow to the heart. Retrograde catheters are placed "backwards" with the end of the catheter pointed away from the direction of venous blood flow. The hypothesis is that retrograde IVs will have a significantly higher success rate of blood draw at the 3 hour time mark without use of a proximal tourniquet.
1. Patients scheduled for surgery under general anesthesia at the University of Iowa Hospitals and Clinics (UIHC) will be recruited pre-operatively in the Day of Surgery Admissions (DoSA) rooms before their surgery takes place. Once the subject is recruited and has signed a consent form, they will be randomized to either retrograde or antegrade IV. Once in the operating room and general anesthesia has been induced, a 20 gauge 30 millimeter catheter will be placed in a vein of one of the upper extremities by an anesthesiologist member of the research team. A drape will obscure viewing of the procedure by the clinical anesthesia provider. They will then connect the catheter to an IV tubing set and cover the insertion site with a opaque towel, so as to blind the anesthesia provider caring for the patient in the OR. 2. 0.9% normal saline (NS) will be infused at a rate of 20 milliliters (mL) per hour to keep it open (TKO) and it will not be used for drug infusion. 3. Three hours after insertion, the anesthesia provider in the OR will attempt a blood draw from a stopcock 33 inches from the catheter. A successful 20 mL blood draw must be achieved within 2 minutes after attempt is started or it will be defined as a failed attempt. If blood draw fails, an upper arm tourniquet will be placed and the blood draw will be reattempted following the same guidelines as the initial attempt. After every blood draw, 10 mL of NS will be flushed back through the IV. 4. At the end of surgery, within 30 minutes of extubation, the anesthesia provider in the OR will attempt a blood draw from a stopcock 33 inches from the catheter. A successful 20 mL blood draw must be achieved within 2 minutes after attempt is started or it will be defined as a failed attempt. If blood draw fails, an upper arm tourniquet will be placed and the blood draw will be reattempted following the same guidelines as the initial attempt. After every successful blood draw 10 mL of NS will be flushed back through the IV. 5. The IV will be saline locked at the end of the case. 6. The IV will be removed within 15 minutes upon arrival in the Post Anesthesia Care Unit (PACU) by the same anesthesiologist member of the research team who placed it and the site will be dressed appropriately. 7. Follow up will happen on post-operative Day 1 (POD1) either in person if the patient is admitted to a UIHC inpatient unit or via a phone call if they are discharged before POD1. At this POD1 check, the patient will be asked about the prior IV site: level of pain, if there is a hematoma, or possible infection. There will be a maximum of 3 attempts to contact the subject. This data will be gathered by a research coordinator member of the research team who is unaware of which study arm the subject was randomized to. 8. A second follow up will happen on 14 days after the surgery/IV placement via a phone call. Again, the patient will be asked about the prior IV site: level of pain, if there is a hematoma, or possible infection. There will be a maximum of 3 attempts to contact the subject. This data will be gathered by a research coordinator member of the research team who is unaware of which study arm the subject was randomized to.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
SUPPORTIVE_CARE
Masking
TRIPLE
Enrollment
230
The region of the upper extremity in which the IV will be placed will be prepped with chlorhexidine and a proximal elastic tourniquet is applied to the upper arm. A 20 gauge 30 millimeter IV catheter is inserted into an upper extremity vein by an anesthesiologist in either an antegrade or retrograde direction depending on which treatment arm the study subject is randomized to.
A 20 milliliter(mL) syringe will be connected to the study IV tubing and used to aspirate 20 mL of blood from the study IV catheter. If 20 mL are unable to be aspirated over a 2 minute time frame, a proximal rubber tourniquet will be applied to the upper arm and the blood draw will be reattempted.This will occur twice throughout the study.
A 20 gauge 30 millimeter long BD Insyte(TM) Autoguard(TM) angiocatheter will be used for peripheral intravenous catheter placement as described above.
After placement of the peripheral intravenous catheter, an infusion of 0.9% normal saline will be connected to the catheter and infused at a rate of 20 milliliters per hour to keep open (TKO) for future use by preventing blood clot development within the catheter.
University of Iowa Hospitals and Clinics
Iowa City, Iowa, United States
Ability to aspirate blood samples without tourniquet 3 hours after IV insertion
As compared to IV catheters placed in the standard antegrade fashion, do IV catheters placed in a retrograde direction have a higher blood draw success rate 3 hours after initial insertion, without the use of a tourniquet? Investigators define "blood draw success" as the ability to aspirate 20 mL blood samples within a 2 minute time frame. It is defined as a binary outcome variable: success vs failure. For the primary comparison of success rates in the retrograde vs antegrade IV groups, chi-square test will be used.
Time frame: three hours after IV insertion
Ability to aspirate blood samples without tourniquet at the end of surgery
As compared to IV catheters placed in the standard antegrade fashion, do IV catheters placed in a retrograde direction have a higher blood draw success rate greater than 3 hours after initial insertion, without the use of a tourniquet? Investigators define "blood draw success" as the ability to aspirate 20 mL blood samples within a 2 minute time frame. It is defined as a binary outcome variable: success vs failure. For the primary comparison of success rates in the retrograde vs antegrade IV groups, chi-square test will be used.
Time frame: three to eight hours after IV insertion
Ability to aspirate blood samples with tourniquet (if needed) 3 hours after IV insertion
As compared to IV catheters placed in the standard antegrade fashion, do IV catheters placed in a retrograde direction have a higher blood draw success rate 3 hours after initial insertion, with the use of a tourniquet (if needed)? Investigators define "blood draw success" as the ability to aspirate 20 mL blood samples within a 2 minute time frame. It is defined as a binary outcome variable: success vs failure. For the primary comparison of success rates in the retrograde vs antegrade IV groups, chi-square test will be used.
Time frame: three hours after IV insertion
Ability to aspirate blood samples with tourniquet (if needed) at the end of surgery
As compared to IV catheters placed in the standard antegrade fashion, do IV catheters placed in a retrograde direction have a higher blood draw success rate greater than 3 hours after initial insertion, with the use of a tourniquet (if needed)? Investigators define "blood draw success" as the ability to aspirate 20 mL blood samples within a 2 minute time frame. It is defined as a binary outcome variable: success vs failure. For the primary comparison of success rates in the retrograde vs antegrade IV groups, chi-square test will be used.
Time frame: three to eight hours after IV insertion
Body mass index (BMI) as a predictor of success rate of blood draws 3 hours after IV insertion.
As an exploratory analyses, the effect of BMI as a predictor of success rate of blood draws will be assessed by including the BMI in the logistic regression model where the outcome of interest is the successful blood draw 3 hours after initial insertion.
Time frame: three hours after IV insertion
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