The Usual Suspects

• Hemolysis: Red cells breaking open and releasing hemoglobin into the plasma, which interferes with many analytes. Classic causes include traumatic venipuncture, long tourniquet time, and fingertip squeezing none of which apply to Rythm's vacuum-assisted upper-arm collection. Vigorous shaking and temperature extremes can still cause it.

• Clotting: Even a small clot can obstruct an analyzer probe. Lithium heparin greatly reduces the risk, but the tube needs your gentle inversions right after collection. If it happens, it doesn't necessarily mean you did anything wrong; occasionally a collection simply flows slowly.

• Lipemia: Very high circulating lipids clouding the plasma, often after a high-fat meal, which can interfere with selected methods.

• Insufficient volume, leaks, or tube damage: Analyzers have sample volume minimums, and any breach of the primary container means mandatory rejection.

If Your Tasso+ Fills Slowly

Keep the arm relaxed and hanging naturally. Warmth, gentle movement, and letting the arm rest below heart level all help. Don't repeatedly flex or squeeze around the device, a prolonged collection is what invites clotting.

Got Most Results, but One Marker Missing?

Different biomarkers have different volume, interference, and stability requirements. The lab may have plenty of usable sample for the panel while one specific test can't be completed or confirmed, in which case Rythm withholds that result rather than estimating it. And if your tube didn't fill completely, send it anyway unless your instructions say otherwise: there's often enough to complete much or all of the panel.