Clonus check

  1. Hi all,
    I've only had a couple of pts on Magnesium, and we do clonus checks on them. I have a couple of things I need some help with. I am pretty sure of my technique, but I just want to double check it with what you guys are doing out there. Also, I never have completely understood the phys behind the checks w/ mag.
    I hope this doesn't sound too ignorant, but it crossed my mind the other day that I should really start getting a grasp on everything I can and the reasoning behind it sooner rather than later (although there is so much to learn in L&D!).
  2. Visit pebbles1977 profile page

    About pebbles1977

    Joined: Jun '04; Posts: 85


  3. by   SmilingBluEyes
    I am unclear, how is it we can help you? With technique? Or with rationale? Sorry, I am just not sure what you are looking for!
  4. by   pebbles1977
    Ok, sorry if I wasn't clear. I hope this can help. It's where you take the pt's foot and kinda roll it side to side and then check to see if it spasms. Does that make sense? We do it for pts on mag.
  5. by   SmilingBluEyes
    No I know what testing for clonus is, what I am asking is what you need help with specifically, regarding this. Sorry I must be reallly slow today. Bear with me.
  6. by   pebbles1977
    Lol, I guess that makes 2 of us!
    I just wanted to check my technique against what others were doing to make sure I was doing it correctly, as well as find out the reasoning behind the checks. Like what in Mag would cause a positive, and why?
  7. by   SmilingBluEyes
    Ok I now get it rofl.....well, even with magnesium, nervous system excitibility can occur if levels are not therapeutic. We are required to do reflex checks q2 hours on all mag patients, whether it's being used for pre-eclampsia or PTL. To check clonus, I take the foot in hand and gently dorsi-flex it toward the shin. Then I let it drop by removing my hand from support. If the foot does a "rabbit hop" or oscillates, you count how many times, and that is how "beats" of clonus you have elicited. does that help? Also when doing this, make sure the leg is completely relaxed as possible, as in checking patellar reflexes.
  8. by   carvanaragon
    magnesium sulfate is a treatment given for pre ecclampsia and ecclampsia to prevent seizures which causes more harm to mom and baby. given to preterm labor to arrest uterine contractions. there is a very thin line that separates the therapeutic and toxic levels of mgso4 such that it is important to know when safe doses has been exceeded. early symptoms noted with mgso4 toxicity are nausea, flushing, palpitations, headache and hyporeflexia. among these hyporeflexia is the more specific one. so that MDs usually orders close monitoring of reflexes (usu hourly) and usually checks levels of mgs04 in the urine constantly. a more serious symptom of toxicity are chest pains, lethargy, visual disturbances (patient complains of double vision), and generalized muscle weakness. late symptoms of toxicity include respiratory depression, pulmonary edema (heard as rales per lung auscultation), cardiac conduction defects and cardiac arrest. minimal handling of this patients and dimly lighted room is also adviced. hope this helps.
  9. by   pebbles1977
    Thanks so much guys.

    When I was taught, my preceptor showed me to roll the foot in a couple of circles then dorsiflex and let go. I wonder what the purpose of the rolling is? To relax maybe?
    OK, so another question. If mag causes decreased reflexes, what mechanism is it that would cause the clonus? Does that even make sense?
    I appreciate your patience with me!
  10. by   BRANDY LPN
    You are not checking clonus just as a side effect of the Mag, you are also checking to see if your pt has a theraputic Mag level, where you want to make sure you don't have HYPO reflexia you also need to prevent HYPER reflexia in a pt with pre-eclampsia- if you had a positive clonus you may have a seizure. I hope that makes sense I know what I'm trying to say it just isn't easy to explain.

    edited to try to make this make more sense:

    You are giving the Mag (in PIH) to prevent a seizure, so in addition to checking DTRs for Mag toxicity you are also assessing the pt for impending convulsions. Someone already listed the sx of Mag toxicity you need to watch for, but you also are assessing the outcome of your treatment, sx of impending eclampsia are epigastric pain, N/V, blurred vision, headache, and increased DTRs. Extrememly brisk DTRs and clonus indicate extreme neuromusclar irritation and danger of impending convulsions.

    So to answer your question the Mag doesn't cause the clonus, it is used to prevent it.

    Hope that helps.
    Last edit by BRANDY LPN on Jan 24, '05
  11. by   SmilingBluEyes
    Clonus is caused by nervous system excitibility secondary to high blood pressure/pre-eclampsia. It CAN, but does not always, precede eclampsia, or seizure. Hope this helps. It is but ONE part of the overall assessment for pre-eclampsia/eclampsia and is useful when assessed with lab values, other nervous systems signs and symptoms and patient complaints, as listed above.
    Last edit by SmilingBluEyes on Jan 24, '05