How long should heparin be paused before drawing blood?
o If you are drawing a Heparin Unfractionated: If drawing from the same arm that the IV is in the IV must be turned off for 10 minutes.
Do you pause heparin drip before drawing PTT?
A 15 minute stop in the heparin is also enough to potentially alter the ptt, so you'd be adjusting the drip to an inaccurate result. Even if you're drawing from a PICC/central line where the heparin is running, pausing the drip and using a thorough flush is still sufficient.
How often do you draw PTT on heparin drip?
For patients on continuous unfractionated heparin, infusion blood is drawn every 6 hours to facilitate dosing adjustments.
Why is heparin monitored by PTT?
PTT may be used to monitor heparin as an alternative to anti-Xa levels in patients with hyperbilirubinemia, hemolysis, hypertriglyceridemia, or direct factor Xa inhibitor use that might interfere with anti-Xa levels.
What is the heparin protocol?
Heparin in a fixed low dose of 5000 U SC every 8 or 12 hours is an effective and safe form of prophylaxis in medical and surgical patients at risk of venous thromboembolism. Low-dose heparin reduces the risk of venous thrombosis and fatal PE by 60% to 70%.
How long can a heparin drip be paused?
One study suggests a wait time of 10 minute after stoping the infusion before drawing the sample". It applies to all infusions, not only Heparin. Our concern is that stoping Heparin for 10 minutes is too long and might show skewed results...
What should PTT be on heparin drip?
Heparin bolus IV Push x1, followed by initial infusion. NOMOGRAM RATE ADJUSTMENT: HIGH INTENSITY HEPARIN with Goal PTT: 60-90 secs PRN boluses per nomogram below require an MD/LIP order.
When would a serum PTT need to be drawn for a patient on a heparin drip?
If the patient is receiving heparin by intermittent injection, the sample should be drawn 30-60 minutes before the next dose, while, if the patient is receiving a continuous heparin infusion, the sample can be drawn at any time.
Does heparin affect PT or PTT?
Heparin typically prolongs the aPTT alone (because PT reagents contain heparin-binding agents that block heparin effect), but at high levels heparin can prolong both tests. Direct thrombin inhibitors (argatroban, dabigatran) typically prolong both tests, but at low levels dabigatran may not prolong the PT.
Does heparin affect INR or PTT?
Heparin in the sample can artificially increase the INR. Samples for Prothrombin Time tests should not be drawn from in-dwelling vascular catheters since these are flushed with heparin which can contaminate the sample.
Do you monitor aPTT with heparin prophylaxis?
Prophylactic (low dose) heparin does not usually require monitoring. In the event of bleeding on heparin, urgent APTTActivated partial thromboplastin time and Full blood count should be performed.
What is difference between PT and PTT?
The prothrombin time (PT) test measures how quickly blood clots. The partial thromboplastin time (PTT) is mainly used to monitor a person's response to anticoagulant therapies. The international normalized ratio (INR) calculation helps ensure that PT test results are standardized and accurate.
When would a serum PTT need to be drawn for a patient on a heparin drip?
If the patient is receiving heparin by intermittent injection, the sample should be drawn 30-60 minutes before the next dose, while, if the patient is receiving a continuous heparin infusion, the sample can be drawn at any time.
How long should an IV be turned off before drawing blood?
CLSI guidelines go on to give recommendations about techniques for drawing below (distal to) an IV catheter, recommending that the IV be turned off for two minutes or longer and that a tourniquet be placed between the IV site and the blood draw site.
Can heparin drip be stopped?
Anticoagulation treatment during extracorporeal membrane oxygenation (ECMO) treatment is unavoidable. However, discontinuation of heparin infusion is necessary when challenges associated with the use of heparin, such as bleeding and thrombocytopenia, are encountered.
Can you draw PTT from Port?
Although bloods can be drawn via an implanted port, there may be times when: i. a peripheral blood draw is required (e.g. certain labs, such as PTTs) ii. it is not feasible for the nurse/clinic to do so.
Do you stop the infusion when drawing from a PIV?
There should be no need to stop the infusion when drawing from a PIV, especially on the opposite arm from the infusion. If the same extremity must be used, then draw from the opposite vein. eg if infusing into the cephalic, draw from the basilic.
Does heparin adsorb to the intraluminal wall?
There are many ways that drugs like heparin can adsorb to the intraluminal walls - some adsorb to the plastic material and other to the intraluminal biofilm. There is hardly any amount of flushing that will remove these adsorbed drugs.
Can you draw coags from a lumen?
So your policy should be to not draw any coags from a lumen that has been exposed to heparin in any dose. Stopping or pausing the infusion sounds like you might be asking about drawing from one lumen while the heparin is infusing through another lumen.
How often should heparin be monitored?
We suggest using anti-Xa level monitoring in patients with heparin resistance, a prolonged baseline aPTT or altered heparin responsiveness. We suggest the aPTT or anti-Xa level be checked every 6 h until two consecutive therapeutic results are obtained, after which the frequency of monitoring can be extended to once daily.
What is the therapeutic range of heparin?
The CAP suggests the one-time establishment of a heparin concentration-derived aPTT therapeutic range. The cumulative summation method is suggested for range re-evaluation following reagent/instrument change. When anti-Xa monitoring is used, a therapeutic target of 0.3–0.7 units/mL is suggested.
What is the aPTT test?
The aPTT, which measures the function of the intrinsic and common clotting pathways, is the most commonly used laboratory test to monitor heparin. Numerous variables impact the aPTT result including pre-analytic (sample collection and processing), analytic (reagent and instrument) and biologic factors (level of clotting factors) [18]. Over 300 different reagent-instrument combinations are used clinically. A therapeutic heparin level (0.3–0.7 u/mL) by anti-factor Xa (anti-Xa) analysis can produce aPTT ratios ranging from 1.6–2.7 to 3.7–6.2 times control depending upon the reagent/coagulometer combination [11]. In response to the numerous limitations of the aPTT, researchers have evaluated direct heparin concentration monitoring using heparin anti-Xa levels. Compared to the aPTT, the heparin anti-Xa level is less impacted by biologic variables, but pre-analytic and analytic variability remain and can be considerable [19]. The anti-Xa is also more expensive than the aPTT, and is both less available and less familiar to clinicians.
How much heparin should I infuse for VTE?
In 1993, Raschke et al. compared weight based heparin dosing (80 units/kg followed by 18 units/kg/h) to a standard regimen (5000 units followed by 1000 units/h) in 115 patients with venous or arterial thrombosis [6]. A five-fold reduction in recurrent VTE was observed with weight-based dosing (95 % CI 1.1–21.9). Nevertheless, most VTE treatment trials incorporated a fixed dose initial heparin infusion regimen of 5000 unit bolus followed by infusion of approximately 1300 units /h [7]. In 1992, the ACCP VTE treatment guidelines suggested a 5000–10,000 unit bolus followed by a fixed heparin infusion of 1300 units/h (31,200 units/day) and in 1995 and 2004 they endorsed either a fixed regimen or the Raschke weight based regimen [8–10]. For a 70 kg patient, the Raschke regimen translates into a heparin bolus of 5600 units followed by infusion of 1260 units/h. The 2012 version of the guidelines do not address UFH dosing in the VTE treatment chapter [11]. However, in the chapter on parenteral anticoagulants, UFH dosing recommendations are similar to those in 1995 and include either a weight based regimen (Raschke regimen) or a fixed regimen of 5000 unit bolus followed by a continuous infusion of at least 32,000 units/day [12].
Is heparin anti-XA better than aPTT?
A recent review identified the potential advantages of the heparin anti-Xa level over the aPTT for heparin monitoring. Advantages included fewer monitoring tests, fewer dose changes and a shorter time to obtain therapeutic anticoagulation [20]. Large VTE trials evaluating patient outcomes with heparin anti-Xa level monitoring are not available. Although both the aPTT and the anti-Xa level can be used to monitor heparin, paired results within individual patients are often discordant [21]. In a recent trial in which clinical outcomes of aPTT versus anti-Xa monitoring were evaluated, a disproportionate prolongation of the aPTT relative to the anti-Xa level was the most common discordant pattern [22]. Patients with relatively high aPTT to anti-Xa levels had higher rates of major bleeding and death compared to patients with concordant paired test results. National guidelines for heparin monitoring recognize the limitations of both approaches without recommending a preferred approach [23].
Is heparin used for venous thromboembolism?
Heparin has been a component of the initial treatment of venous thromboembolism (VTE) for decades. Despite its long history, various aspects of the practical use of unfractionated heparin (UFH), whether delivered intravenously (IV) or subcutaneously (SC), continue to challenge clinicians. In 1998, the US FDA approved the low molecular weight heparin (LWMH) enoxaparin (Lovenox) for VTE treatment, followed by approval of the synthetic heparin-like compound fondaparinux (Arixtra) in 2004. In 2007, the LMWH dalteparin (Fragmin) was approved for VTE treatment in patients with cancer. These agents, intended for subcutaneous administration, offer practical advantages over unfractionated heparin, yet present their own challenges, particularly in special populations. This chapter will address the practical use and management of the parenteral heparin anticoagulants available in the US when used in the treatment of VTE.
Is anti-XA level monitored with heparin?
Direct anti-Xa level monitoring is recommended in those with heparin resistance (see subsequent section), baseline aPTT elevation from a lupus anticoagulant or contact factor deficiency or those with markedly elevated levels of fibrinogen or factor VIII [24].
How long should I wait to draw blood from an IV?
CLSI guidelines go on to give recommendations about techniques for drawing below (distal to) an IV catheter, recommending that the IV be turned off for two minutes or longer and that a tourniquet be placed between the IV site and the blood draw site. Finally, the guidelines mention that collection above (proximal) to the IV catheter is not recommended and should be done only when all other options for blood collection have been exhausted. Getting back to the question in this case, to find an answer we should further investigate the data in the studies that were mentioned or referred to in the CLSI guidelines and data from other studies or relevant Mayo Clinic experience.
Can you draw from the opposite arm?
You can only draw from the opposite arm.
Can you draw from the same arm as an IV?
Q: In a patient with an IV catheter, you may draw from the same arm that has the IV catheter if . . . You may only draw above the IV. You can draw below the IV with a tourniquet between the IV site and the draw site. You can only draw from the opposite arm. The available data suggest that the second and third options are equally appropriate.
Is the site of draw important?
Although there is not a lot of data published on this issue, it is likely that site of draw —that is below the IV catheter with a tourniquet or from the opposite arm—is less important than timing of the blood draw for calcium, magnesium, and phosphorus relative to when intravenous infusions are stopped.
Can you draw blood from IV arm?
Ong YY, Boykin SF, Barnett RN, et al. You can draw blood from the "IV arm" below the intravenous needle if you put a tourniquet in between. Am J Clin Pathol. 1979;72 (1):101-102.
