Administration

Home
Up

TPN administration

1. Initiation - TPN solutions should be infused slowly with small increases in the rate of the first TPN to avoid hyperglycemia.

Start 50 ml/hr x 4 hours,

then 75 ml/hr x 4 hours,

then 100 ml/hr x 4 hours

then increase to final rate.

Blood glucose determinations (accu-chekR) should be done before each rate increase. If the blood glucose is greater than 200, continue at the same rate for another 4 hours, check again and if still high, consider insulin therapy. If patient is diabetic; see section on TPN in various disease states.

2. Cessation - patient can be weaned from TPN rapidly. Decrease the rate by 1/2 every 2 hours until the rate is less than 50 ml/hr, then discontinue.

3. Cyclic TPN administration - Cycling is a procedure used especially in the outpatient setting to free the patient from being attached to an IV and allow for ambulation. There are no specific written guidelines on how to convert patients to cyclic TPN although the following information is generally considered to be helpful. The patient must be stabilized on the 24 hour schedule. The maximum hourly rate tolerated for a TPN is usually about 200 ml/hr. Advance to the final time period slowly by subtracting 2-4 hour blocks of time from the total daily infusion time. It will take several days to reach the final infusion time. Monitor vital signs, input and output, and glucose with accuchecks carefully during the change over period as the patient may require additional time to adjust to new regimen.

To convert a patient from a 24 hour TPN to cyclic TPN the following is suggested:

Total daily TPN volume/(Total hours to deliver TPN - 1) = Final cyclic TPN rate

Approximately 1/2 of the final hourly cyclic TPN rate is usually sufficient for a 1 hour advancing and decreasing taper. Refer to example below. Advancing tapers at an initial rate exceeding 80 ml/hr should probably be changed to deliver 35% of the final rate over the first half hour and 65% of the final rate over the second half hour.

For example a 2400 ml TPN is running at 100 ml/hr over 24 hours. To convert to a cyclic TPN:

20 hr delivery: 2400/19=126 ml/hr x 18 hours which is a total of 2268 ml.

2400-2268=132 ml. One hour start and stop taper=66 ml/hr

16 hr delivery: 2400/15=160 ml/hr x 14 hours which is a total of 2240 ml.

2400-2240=160 ml. One hour start and stop rate=80 ml/hr.

12 hr delivery: 2400/11=218 ml/hr x 10 hours which is a total of 2180 ml.

2400-2180=220 ml. One hour start and stop rate =110 ml/hr. This rate may be too fast as a start rate and a slower rate for the first 1/2 hour and last 1/2 hour of the taper may be required. Consider delivery of 35% of this rate over the first half hour (77 ml/hr) and 65% (142 ml/hr) over the second half hour which would equal a one hour start volume of 110 ml/hr. Taper the rate to 142 ml/hr for a half hour and then 77 ml/hr for a half hour when stopping the cyclic TPN.

Fluid volume and infusion rates

Infusion rates must be ordered so the total fluid volume is given over 24 hours. If following the recommended initiation schedule, the first 24 hour bag should be written for 2400 ml.

FLUID VOLUME/24 HOURS            INFUSION RATE

1000 ml                                                     42 ml/hr

1200 ml                                                     50 ml/hr

1800 ml                                                     75 ml/hr

2000 ml                                                     83 ml/hr

2400 ml                                                     100 ml/hr

3000 ml                                                     125 ml/hr

3600 ml                                                     150 ml/hr

3-in-1 admixtures

Recommended only if the patient's additive profile is compatible with 3-in-1 mixing. Pharmacists will verify compatibility and will contact the physician if there are problems. Patients who show a rapid elevation of triglycerides to greater than>400 mg/dL upon fat emulsion infusion would NOT be candidates for 24 hour 3-in-1 admixtures.