Reply To: HD MTX completion

  • Katherine Dodge

    November 18, 2019 at 1:31 pm

    Hi Kelly,

    I’ve noticed the same issue with our 24 hr MTX infusions. It is impossible to accurately measure how much is left in the back by eyeing it. And with the interruptions that come from line occlusions, ADLs, or pump errors… it’s almost impossible to get the MTX done in exactly 24 hours. Either it’s a little early or there’s volume left in the bag.

    Our facility has a rule where we check the remaining volume when there is 8 and 4 hours left in the infusion timing, this way we are somewhat more accurate about getting the volume in, but the process isn’t perfect. Even on other chemo meds that run over a shorter amount of time there have been issues with excess volume being left in the back after the prescribed amount has been infused. Pharmacy states that they only fill the bag with the recommended amount of medication/dilution volume and will blame the pump or the RNs for entering the volume wrong… even if the pump’s programming shows the correct volume and timing and is reflected in the RNs charting.

    Honestly I think that weighing the bags for the remaining volume is brilliant… something I had never heard of before, but will definitely be recommending to the powers that be. At least it will give us a more accurate idea of where we are with the remaining volume in a bag that you cannot accurately measure by eyesight alone.
    I wonder how you account for the weight of the bag in your measurements? Any suggestions on that front?


    Katherine Dodge, BSN, RN
    Seattle Children’s Hospital
    Original Message:
    Sent: 11-13-2019 05:13 PM
    From: Kelly Horn
    Subject: HD MTX completion

    We used to weigh our bags of HD MTX + bicarb fluids (we called them big berthas) and we had a relatively small number of issues when weighing.  We also had an order that we could increase or decrease rate by 20% in order to get it to complete in time.  We had to do some adjusting at times, but not much.  When our pharmacists found out we were weighing the bags, they made us stop and we have had nothing but trouble since getting it to finish in 23.5 hours. For 2 years we have been titrating the 24 MTX bags to get them to complete–many titrations–too many. Had to make a change.

    Now, our new process for administering HD MTX for the 24 hour infusion is that the 30 min loading dose is sent in a syringe if < 50 mls which is great, no issues.  Then the 23.5 portion is sent in primary tubing, circle primed with drug in the pharmacy, to be bifused with the sodium bicarb fluids.  We set the pump for 30mls less to account for the tubing so that we can insert the flush into the side port of the set, add the 30mls flush VTBI and it should be done in the prescribed amount of time…only it never is. Pharmacy says they are sending the exact amount of volume and calculate the rate for that total volume for 24 hours. The bicarb runs fine, but we always have to increase the rate of the MTX to get it to finish.

    We also do this for 4 hour HD MTX. Same process.  The bicarb will finish in 4 hours, the MTX has volume left in bag.

    Has anyone else had this experience?  We can’t figure out what is wrong.

    Any help/ideas would be appreciated.

    Kelly Horn, MSN, RN, CPON
    Nursing Professional Development
    McLane Children’s Baylor Scott & White Health
    Temple, TX 76502