phenytoin Injection.pptx- Enhancing safety

Provides knowledge to create awareness on phenytoin injection safety.

1. P h e n y t o i n P r e s e n t e r : C y n thia G e n d i

2. PHENYTOIN PROTOCOL Indication: Phenytoin is used for the treatment of seizures, including status epilepticus, tonic- clonic seizures, and partial seizures. It is also used for seizure prophylaxis in patients with brain injury and during neurosurgery. Phenytoin is NOT meant to be used for sedation. Mechanism of action: protects against seizure by causing voltage _dependent block of voltage-gated sodium channels. This blocks sustained high-frequency repetitive firing of action potentials.

3. Patient Assessment Check patient’s file for diagnosis, current and past medications (including doctors order for medication, taking care to note date, dose, route, time, and duration) allergies, and comorbidities. Perform hand hygiene and glove. Introduce yourself and identify the patient using name and date of birth. Assess patient, including special care to note mental state, any confusion, slurred speech, nystagmus, etc …. Assess IV site for signs of infection(redness, swelling, itching, and pain) Scrub IV access port vigorously with alcohol for a minimum of 15seconds Flush Iv with saline and assess for signs of infiltration…IV that does not draw back or flush, pain, skin blanching or coolness, wet dressings, and local edema.

4. Patient Assessment cont ….. If signs of infection or infiltration, document and remove IV. Replace IV in a different site. For a routine change of peripheral IV site and IV tubing refer to the standard operating procedure on IV therapy. Document all assessment findings and actions in the nursing cardex .

5. Preparation of IV solution Inspect the ampule, making sure the packaging is intact. Check the expiry date Check the ampule against the doctor’s order for the following information : patients name and date of birth, name of the medication, dosage, rate, route, frequency, and time last given DO NOT MIX with D5W, only normal saline Dilution instructions 1. For all doses and routes, mix solution completely until fully dissolved and clear, before use 2. For direct bolus IV injection: Doses greater than 100mg(a typical loading dose) should be mixed with NS and diluted to a concentration no less than 5mg/ml. 3.For intermittent IV infusion: for a 250mg dose, dilute with 50mls NS for a final concentration of5mg/ml. For a 750mg dose, dilute with 100ml NS for a final concentration of 7.5mg/ml.

6. Preparation of IV solution cont …. Storage/discarding instructions: If storing, label medication with time, date, your initials, and time of expiry Discard if a solution is hazy or precipitated Use within1 or 2 hours of mixing. Discard diluted preparations 4 hours after dilution. Do not refrigerate diluted preparations.

7. Dosage and administration Important safety note: Phenytoin has a very small therapeutic window, meaning there is little margin of error between therapeutic and toxic doses. Apart from the loading dose, doses greater than 100mg should not be used on patients who weigh less than 70kg. The typical dose is 2mg/kg every 8 hours. Using higher doses can result in toxicity and should be avoided. a)Typical adult dosing…For status epilepticus:15-20mg/kg IV loading dose, for maintenance:100mg IV three times daily. b)Elderly patients and patients with a renal or hepatic impairment will typically receive lower doses.

8. Dosage and administration cont …. Inspect solution prior to administration it should be completely mixed, dissolved, and clear. Recommend using an inline filter during administration, as crystallization may occur. Use a large vein for administration and at least a 20gauge needle. Prior to administration: i ) check the name, dose, rate, and route of the medication against the doctor’s orders again. ii)check the patient’s name and date of birth

9. Dosage and administration cont ….. Administration rate: i ) Direct IV bolus injection, given at a rate no faster than 50mg/minute. Inject 100mg over 2minutes ii) for elderly patients or patients with pre-existing cardiovascular disease, give no faster than 20mg/minute iii) DO NOT EXCEED 50mg/minute rate. Faster rates of administration can cause severe hypertension and cardiac arrhythmias. iv) flush line before and after with NS to reduce venous irritation at the IV site. v) Intermittent infusion:administer over 30minutes

10. Dosage and administration cont ….. vi)patients should be switched to oral phenytoin 12 to 24 hours after the loading dose, or as soon as possible Contraindications a) Hydantoin hypersensitivity includes, fosphenytoin and ethotoin b) History of hepatotoxicity attributed to phenytoin

11. PRECAUTIONS AND ADVERSE REACTIONS a)Serious cardiovascular reactions can occur, especially if the recommended infusion rate is exceeded. Such events include bradycardia, all of which can result in asystole, cardiac arrest, and death. These events are more common in the elderly, the critically ill patients with pre-existing hypotension or heart disease. b)Anticonvulsants like phenytoin carry an increased risk of suicidal ideation and behavior. Monitor patients carefully for worsening or new depression or suicidal thoughts. Educate patients and their caregivers to report immediately any worsening or new depression, or suicidal thoughts. Self-harm, or unusual mood or behavior changes.

12. PRECAUTIONS AND ADVERSE REACTIONS c)Signs of phenytoin toxicity include CNS effect: nystagmus, ataxia, slurred speech, decreased coordination, drowsiness, and confusion. d)Phenytoin can stimulate glucagon secretion and cause blood sugar to rise. Monitor sugar closely when administering phenytoin to diabetic patients. e)Abrupt discontinuation may cause seizures in epileptic patients. Decrease dose gradually. f)Pregnancy phenytoin is a known teratogen and can cause fetal hydantoin syndrome(dysmorphic skull and facial features, growth abnormalities, and cognitive deficits) phenytoin should not be used in pregnancy Also: paresthesia ,paradoxical, seizure,diplopia , and vertigo

13. Monitoring During phenytoin administration, monitor and document the following: a)ECG b)Full hemogram c)Urea electrolyte and creatinine