KCl and KPhos CRI
Posted: Sunday, October 10th, 2021 | Updated: Sunday, October 10th, 2021
Posted: Sunday, October 10th, 2021 | Updated: Sunday, October 10th, 2021
Doctor's Order:
Start a KPhos CRI at 0.03 mmol/kg/hr and a KCL CRI at 0.2 meq/kg/hr. Combine the CRIs in one syringe and dilute with 0.9% NaCl to run at 1 ml/hr for 12 hours. Take the amount of potassium in KPhos into consideration when calculating the KCl CRI.
Patient Weight:
5 kg
KPhos Concentration:
3 mmol/ml phosphate
4.4 mEq/ml potassium
KCl Concentration:
2.2 mEq/ml KCl
Complete the Math for KPhos:
(0.03 mmol/kg/hr) x (5 kg) = 0.15 mmol/hr of KPhos
(0.15 mmol/hr) / (3 mmol/ml) = 0.05 ml/hr of KPhos
Find How Much Potassium Your Administering From KPhos:
(0.05 ml/hr) x (4.4 mEq/ml) = 0.22 mEq/hr of potassium
Complete the Math for KCL:
(0.2 mEq/kg/hr) x (5 kg) = 1 mEq/hr of KCL
(1 mEq/hr) - (0.22 mEq/hr) = 0.78 mEq/hr KCL needed
(0.78 mEq/hr) / (2.2 mEq/ml) = 0.3545 ml/hr KCL
Complete the Dilution to Equal 1 ml/hr for 12 hours:
(0.05 ml/hr KPhos) x (12 hr) = 0.6 ml KPhos
(0.3545 ml/hr KCL) x (12 hr) = 4.25 ml KCl
(12 ml Total Fluid Volume) - (0.6 ml KPhos + 4.25 ml KCl) = 7.15 ml 0.9% NaCl
The Result:
You will need 0.6 ml of KPhos and 4.25 ml KCl to mix with 7.15 ml of 0.9% NaCl. This will result in a 1 ml/hr total fluid rate for the CRI. This runs the KPhos at 0.03 mmol/kg/hr and the KCl at 0.2 mEq/kg/hr taking into consideration the potassium being delivered from the Kphos CRI
*Note Per Plumb's as of 10/11/21: "Potassium chloride for injection compatibility information conflicts or is dependent on diluent or concentration factors with the following drugs or solutions: fat emulsion 10%, amikacin sulfate, dobutamine HCl, mannitol, methylprednisolone sodium succinate (at Y-site), ondansetron, penicillin G sodium, promethazine HCl (at Y-site), and sodium bicarbonate... Potassium chloride for injection is reportedly physically incompatible with the following solutions or drugs: amphotericin B, diazepam (at Y-site), and phenytoin sodium (at Y-site)." Plumb's also notes, "Phosphates may be physically incompatible with metals such as calcium and magnesium... Potassium phosphate injection is reportedly physically incompatible with the following solutions or drugs: D2.5 in half normal Ringer’s or LRS, D5 in Ringer’s, D10/sodium chloride 0.9%, Ringer’s injection, LRS, and dobutamine HCl."
Start a KPhos CRI at 0.03 mmol/kg/hr and a KCL CRI at 0.2 meq/kg/hr. Combine the CRIs in one syringe and dilute with 0.9% NaCl to run at 1 ml/hr for 12 hours. Take the amount of potassium in KPhos into consideration when calculating the KCl CRI.
Patient Weight:
5 kg
KPhos Concentration:
3 mmol/ml phosphate
4.4 mEq/ml potassium
KCl Concentration:
2.2 mEq/ml KCl
Complete the Math for KPhos:
(0.03 mmol/kg/hr) x (5 kg) = 0.15 mmol/hr of KPhos
(0.15 mmol/hr) / (3 mmol/ml) = 0.05 ml/hr of KPhos
Find How Much Potassium Your Administering From KPhos:
(0.05 ml/hr) x (4.4 mEq/ml) = 0.22 mEq/hr of potassium
Complete the Math for KCL:
(0.2 mEq/kg/hr) x (5 kg) = 1 mEq/hr of KCL
(1 mEq/hr) - (0.22 mEq/hr) = 0.78 mEq/hr KCL needed
(0.78 mEq/hr) / (2.2 mEq/ml) = 0.3545 ml/hr KCL
Complete the Dilution to Equal 1 ml/hr for 12 hours:
(0.05 ml/hr KPhos) x (12 hr) = 0.6 ml KPhos
(0.3545 ml/hr KCL) x (12 hr) = 4.25 ml KCl
(12 ml Total Fluid Volume) - (0.6 ml KPhos + 4.25 ml KCl) = 7.15 ml 0.9% NaCl
The Result:
You will need 0.6 ml of KPhos and 4.25 ml KCl to mix with 7.15 ml of 0.9% NaCl. This will result in a 1 ml/hr total fluid rate for the CRI. This runs the KPhos at 0.03 mmol/kg/hr and the KCl at 0.2 mEq/kg/hr taking into consideration the potassium being delivered from the Kphos CRI
*Note Per Plumb's as of 10/11/21: "Potassium chloride for injection compatibility information conflicts or is dependent on diluent or concentration factors with the following drugs or solutions: fat emulsion 10%, amikacin sulfate, dobutamine HCl, mannitol, methylprednisolone sodium succinate (at Y-site), ondansetron, penicillin G sodium, promethazine HCl (at Y-site), and sodium bicarbonate... Potassium chloride for injection is reportedly physically incompatible with the following solutions or drugs: amphotericin B, diazepam (at Y-site), and phenytoin sodium (at Y-site)." Plumb's also notes, "Phosphates may be physically incompatible with metals such as calcium and magnesium... Potassium phosphate injection is reportedly physically incompatible with the following solutions or drugs: D2.5 in half normal Ringer’s or LRS, D5 in Ringer’s, D10/sodium chloride 0.9%, Ringer’s injection, LRS, and dobutamine HCl."
Sources:
Plumb's. Vers. 2021.9.3. Educational Concepts, LLC. Google Play, https://play.google.com/store/apps/details?id=com.plumbs.app.
Plumb's. Vers. 2021.9.3. Educational Concepts, LLC. Google Play, https://play.google.com/store/apps/details?id=com.plumbs.app.