My Haemoglobin from back end last year to a month ago was between 116 and 121. Hematocrit was 41%. Haematologist wouldn't give me iron tablets as last time hematocrit jumped uo so fast apparently put me at risk of a stroke. Last blood test a month ago Haemoglobin 132 and Hematocrit 47%. Why it jumped up so quick after months being low and doing nothing differently, who knows. Had venesection last Monday and only managed half a bag. After fiddling about with the needle they decided the blood had clotted in the needle. And yes, when they pulled the needle out a long thread of gelatinous blood was trailing out of the needle. Anyone else had this as been having venesections for the last 15 years with no problem. Had PV for 15 years and on Aspirin and venesection.
Jump in Haematocritt: My Haemoglobin from back end... - MPN Voice
Jump in Haematocritt
HGB and HCT are usually correlated in a ratio and rise and fall together. Typically, HCT = approx 3X HGB. With HGB expressed as 12.1, HCT would be expected to = approx 36.3%. HGB 13.2 would predict HCT approx 39.6%.
There are factors that can influence HGB such as iron and Vitamin B levels, and HCT such as hydration and plasma volume. The sudden rise in HCT with HBG being still low is something that needs an explanation.
Suggest reviewing this question with your MPN care team. The MPN Specialist can review your history, order additional tests (e.g., Vit B and iron panels) to shed light on what is going on.
The unusual coagulation you experienced during the venesection is another issue to be explored. Suggest reviewing that issue as well.
Please do let us know what you learn and how you get on.
Thanks Hunter. Good explanation as usual. They have found I'm low on Vitamin B12. I'm now on tablets for 6 weeks to see if I'm not getting enough from food or I'm not absorbing it. Nurse doing the venesection said he's come across blood clotting in needle before, usually the first bag if blood is thick. I've had higher HCT and never had it happen in 15 years. I did mention it at my telephone review with haematology but they didn't say anything. I'll keep you posted.
If you are having trouble absorbing Vit B, then I would consider a more complete nutritional analysis. I did a comprehensive nutritional analysis and was found to be deficient in Vit B/folate, Vit D, and Magnesium. We titrated the doses of the supplements to match my specific needs based on follow up labs.
Do please let us know how things turn out.
mark382 so interesting you bring this up because at my last venesection they were having trouble and blood was coming out around the needle (never happened before). They said it was must likely due to blood clotting in the needle. They tried several sites and it happened each time. No explanation why and in fact, they seemed a bit surprised themselves. My HCT was not very high. It was 42.8 (my cutoff is <42). My HGB was 12.1.
I am also on aspirin (1 low dose twice a day) and venesection only. While I have had my blood clot many times while they were trying to pull it out, due to it being so thick, I've never had it flow out around the needle. Not sure we will ever know for sure why out of the blue it's clotting in the needle.
I also cannot figure out why my HCT goes up or down 5 points all of a sudden. No one seems to have any answers other than, "yes, that can happen". Sometimes I wonder if it's something I ate that was higher in iron (if it shoots up) or eating low iron foods that makes it drop 5 points. My MPN specialist has said food doesn't have a huge impact (not that he wants me going out and eating steaks and other red meat all the time). There is so much unknown about these MPNs that I think we can drive ourselves crazy sometimes trying to figure things out.
Good luck. I hope you get some answers to your questions.
Sometimes no one knows why stuff happens! Like Hunter said can be so many things. I do not work in oncology but I still have to do labs on patients. And sometimes the numbers jump around. I have done so many labs over the years and will have patients recheck labs if they were off of what I had seen before and it normalize in a week or two. But hopefully after this phlebotomy things will straighten out. And Vit B12 can cause some issues with anemia and who bunch of other stuff. Hopefully was just a fluke and you will be back on track. As far as the blood in the needle, what size did they use? 16 or 18? May have just been the needle and the digging. I have learned for them not to touch my right arm! I have a great vein but even lab draws it rolls!
ET, hydrea and feeling fatigued and depressed 
ET with high HCT?
High ferritin post transplant
