Pitocin Dosage Calculations

Doing Pitocin – It’s Easy!!! Drip rates are no different for Pitocin than any other med you might use in clinical. We give it in milliunits per minute or per hour. At least 2 Pitocin drip questions will be on the test. There are always at least one and often 2 of these questions on the ATI, and so probably this is also on the NCLEX. Those of us who do not instinctively understand medication math have to practice, and I am going to give you some hints for doing that. First, know the medications. Oxytocin, or Pitocin is usually given nowadays as a piggyback rather than as the only IV, so that if uterine hyperstimulation (tachysystole) or dangerous decels occur, it can be immediately turned off without having to get a new IV bag to hang to keep the vein open and to keep the fluids going. The concentration is commonly 10 – 20 units per liter, making the amount in a 500 ml bag 20 – 40 units, but the same concentration. You will remember that there are 1000 milliunits in a unit, and Pitocin is given IV in milliunits per hour (or at least most IV pumps ask for ml/hour, so even if we infuse by the minute, we still must know the hourly rate to set up the pump correctly). A common order is to start Pitocin at ½ to 2 milliunits per minute and to increase this every 20 – 30 minutes until contractions are regular and of a strength to be effective, if well tolerated by both mother and fetus, up to a maximum dose of 20 milliunits per minute according to your book. This is typically most hospital protocols as well, however, ensure you know the protocol for where you work if you go into this area after graduation. So, to prepare for the test in regard to Pitocin drips, be able to answer questions that ask what dose of Pitocin is being infused if the pump states ____ ml/hour. Also be able to state how many ml per hour you would set the pump for a dose of ____milliunits per minute. (Note than when giving Pitocin IV after the birth, we are not concerned about decels –since there is no baby in the uterus--so we give much higher doses for treatment or prevention of postpartum hemorrhage. This test is concerning antepartal and birth times, and so naturally before birth occurs, we must be more cautious.) 1. The nurse enters a patient room and sees the IV pump set at 200 ml per hour. The bag of IV fluid is 1000 mL Normal Saline and the label states that the bag contains 10 units of Pitocin. How much Pitocin is the patient receiving in milliunits (mu) per minute? Answer: 10 units of Pitocin equals 10,000 milliunits, so the bag contains 10,000 milliunits total. How many milliunits per ml? 10,000 divided by 1000 is 10 – there are 10 milliunits per 1 ml. The patient is receiving 200 ml per hour, and each ml contains 10 milliunits. 200 X 10 = 2000. The patient is receiving 2000 mu/hr. Divide by 60 to determine mu/minute: 33.3333 mu/min= 33.3mu/min (This is a medication – so rounded to 10ths) 2. Your textbook states to start Pitocin drips at 1 mu/min. At how many ml per hour should the nurse set the IV pump for this dosage? The IV bag is 1000 ml and contains 20 units of Pitocin. Answer: 20 units of Pitocin equal 20,000 mu per liter. How much per ml? _______ Divide 20,000 mu by 1000 mu (there are 1000 mu per unit) to get 20 mu per ml. Now determine how much IV fluid has 1 mu, sine that is the amount we need to give per minute. 20 mu/1ml = 1 mu/?/ml. At this point set up your fraction with the numerators directly over the denominators. You need to make the proportions equal – 20mu/1 ml X 1mu/?? ml = 1mu/min (the ordered starting dose) (Divide 1mu/min (ordered amount) by 20 mu/ml (available amount). You will get 0.05 ml/min. You must set the pump at ml/hr. So, 0.05ml X 60min = 3ml/hr (= 1 mu/min) 3. A nurse is the patient in the Labor and Delivery Unit. She feels that her contractions are too strong and on her own, turns down the IV pump. (The concentration of Pitocin is 30 units to 500 ml NS. The rate is currently 30 ml per hour. What dose is the patient receiving? Answer: First, find out how much is in each ml and go from there. If there are 30 units in 500 ml, how many mu are in 500ml? ______ (30,000 mu/500 ml). How many mu are in each ml? _______ (30,000 mu divided by 500 ml) There are 60 mu in each ml, and the patient is getÝng 30 ml per hour = _______ mu/hr (60 mu X 30 ml = 1800 mu/hr) How many mu/min? _______ 1800mu divided by 60 minutes = 30 mu/min) 4. In report, the off-going nurse tells the on-coming nurse that the patient is receiving Pitocin at 6 mu/min. What should the pump setÝng be? The IV is 10 units Pitocin in 1 liter NS. (Remember, pumps are usually designed to give ml/hours, not mu/min). Answer: 10 units/1 liter = _______ mu per ________ ml (10,000 mu/1000 ml = 10 mu/1ml) The patient is supposed to be getÝng 6mu/min. Determine how many mu/hour the patient is getÝng: 6mu/min = 360mu/hr (6mu X 60min) Now determine how many ml/hour you need: 360mu = ________ ml? (1ml=10mu therefore, 360mu/hr divided by 10 mu= 36 ml/hour 5. 130 ml per hour is infusing according to the IV pump. How much Pitocin is the patient receiving? The concentration is 20 units per 1000ml. You figure this one out________________ 6. Begin a Pitocin infusion at 2 mu/min via IV pump for labor induction. On hand is Pitocin 20units in 500ml Lactated Ringers. How many ml/hr will the IV run? _________________ 7. The nurse notes the patient’s IV pump is set at 7ml/hr. The IV bag holds 40 units of Pitocin mixed in 500ml of Lactated Ringers. How many mu/min is the client receiving? ________________ 8. The order is for Pitocin at 12mu/min. On hand - 20 units of Pitocin mixed in 1000 ml of Lactated Ringers. The pump should be set at: ________________ Answers (Don’t cheat!! 😊 FF FFFF FFFFF FF FFF FFF FFFFFFFFF F FFFF! ) 5. 130ml/hour = ? mu/min 20 U in 1000ml RL 20U = 20,000mu divided by 1000ml = 20mu/ml 130mu/hr X 20mu/ml= 2600mu/hour 2600mu/hr divided by 60 minutes = 43.33 mu/min = 43.3 mu/ml 6. Begin at 2mu/min. 20U in 500ml 20,000mu/500ml = 40mu/ml 2mu/min X 60 min = 120mu/hr divided by 40mu/ml = 3ml/hr FFF FF FF FFF FFFFF 7. Pump at 7ml/hour. 40U/500ml = 80mu/ml 80mu/ml X 7ml/hour = 560mu/hr divided by 60 min = 9.33mu/min = 9.3mu/min 8. Order for 12mu/min. 20U/500ml = 20mu/ml 12mu/min X 60min = 720mu/hr divided by 20mu/ml = 36ml/hour