Apheresis Day Two

Day 117 (D -21)

Today we are back in the apheresis lab for Ann's second day of collection. It was actually a bit of a surprise start for the day because MDA called us early this morning and asked us to come in. Normally the apheresis clinic is packed, not because there are lots of patients, but because each collection can take upwards of 4 hours. So getting here early is really a bonus because we won't have to wait until after 6 to get back to the apartment.

Dawn, our apheresis nurse, told us that yesterday's collection looked really good. MDA's labs confirmed the collection of 1.6 million CD34 cells (aka stem cells) out of the target of 5 million. We also found out another very interesting side effect of neupogen...in addition to rotten bone pain it causes fevers! Well low grade fevers anyway, but it still freaked me out when Ann's temp registered at 100.5 F today. I was ready for the apheresis to be aborted and have her check into the hospital for a week of IV antibiotics. However, Dawn put my mind at rest and said Ann is not having any other symptoms (chills, sweats, trouble urinating, etc, etc) and neupogen causes fever spikes sometimes. Especially at the levels she is taking (900 mg per day). Sure enough 30 minutes later her temperature was back down to 98.7 F and then a hour later it was all the way down to 97.4 F.

From a technical POV the collection process is pretty interesting. The apheresis filter is really a collection of peristaltic pumps and a high speed centrifuge. Blood is drawn from the patient (Ann who is currently being impossibly cute) and pumped into the centrifuge. There the angular velocity causes the blood to separate based on relative density. RBCs are the most massive and settle to the bottom. Plasma is the least massive and ends up on the top layer. WBCs and Platelets occupy the layers in between.

In this middle area is a small band where the CD34 Cells fall out. A tube and trail and error are use to siphon them off. The positioning of the different blood layers is controlled by adjusting the speed the centrifuge is rotating at since the collection tube is mounted statically in the incoming blood from the patient. Once gathered the stem cells are mixed with a preservative (DMSO) and pumped into a collection bag. Funny that so much fun is poked at engineering by the Docs over here when this collection of PDPs, motors and feed back controls is relied on so heavily to treat cancer patients.

The apheresis lab is incredibly cold most of the time, probably to keep down the chances of damaging the blood stem cells being collected. So in the 4 hours or more that a patient (and her husband) will be there it is necessary to dress like its January in Main and not May in Texas. In this picture you can see Ann has about 4 blankets piled up on top of her while she passes time watching MPGs on her laptop.

To help keep the patients warm the apheresis lab has blanket warmers. These can hold up to 50 clean blankets and heat them up to about 90 F or so. The effect is just like grabbing clothes just out of the dryer and they seem to do the trick for helping the patients keep warm.

For everyone who ever wondered what blood stem cells/bone marrow looks like, the picture on the left should satisfy your curiosity. This is a picture of the cells that they collected from Ann yesterday.

One last thing...I discovered today that MDA has installed cellphone scramblers at various points of the building to protect their telemetery from some labs and wireless data systems. So if anyone has been trying to call us while we are at MDA and gets dumped to voice mail then that's the reason. The problem is compounded with some sort of screw up Sprint is currently having, which messed up my aircard and put a big delay on our voice mail notification. Which is also if you haven't guess is the reason this post is so late.

Anyway more tomorrow. Night everyone.