- You must administer surgical prophylaxis at the time of the first incision or as close as possible. Redose if surgery is longer than four hours. No need for post-op, except in cardiac procedures.
- Usually use cefazolin 2 g (3 g for patients above 120 kg), ceftriaxone, cefotetan, cefoxitin 2 g, clindamycin 900 mg, vancomycin 15 mg/kg
- Cefazolin 2g is preferred in most cases, one dose unless surgery > 4 hours or cardiac procedures
- Prophylaxis by surgical procedure
- GI: Cefazolin 2g
- Billary: Cefazolin, cefoxitin, cefotetan or ceftriaxone 2g, or amp/sulbactam 3g
- Appendectomy: cefoxitin or cefotetan 2g or cefazolin + metronidazole (anaerobic coverage)
- Colorectal: cefazolin or ceftriaxone 2g + metronidazole with or without neomycin and erythromycin
- Gynocological: cefazolin, cefoxitin or cefotetan 2g
- Cardiac: cefazolin or cefuroxime 2g
- Orthopedic – cefazolin 2g
- Urologic: None
- Prophylaxis by surgical procedure
Uncategorized
Seizures: Epilepsy
*See the seizure medication table for quick reference.
*Seizure Emergencies
Epilepsy Treatment Options:
Know doses for narrow therapeutic index drugs like phenytoin, but mostly need to know what kind of seizure and major side effects that would cause you to choose a different therapy. Also know REMS programs.
- Benzos can be used as adjunctive, short-term therapy (clorazepate, clonazepam, diazepam or lorazepam)
- Brivaracetam
- Carbamazepine – Beware of Stevens Johnsons syndrome with carbamazepine, induced its own metabolism, pharmacogenomic considerations (HLA-B testing in Asians), blood disorders
- Eslicarbazepine
- Ethosuximide – Absence seizures
- Felbamate in severe, refractory seizures. Severe side effects: aplastic anemia, liver damage. Adjunct for Lennox-Gestault
- Fosphenytoin
- Gabapentin – Also for peripheral neuropathy
- Lacosamide – partial onset seizure, increases suicidal ideation
- Lamotrigine – Adjunct for partial, bipolar, Lennox-Gestault. Valproate inhibits the metabolism (must lower dose). Carbamazepine induces metabolism. Titrate to avoid Stephen-Johnson’s syndrome. Estrogen induces metabolism (increase dose). Good for patients with sexual dysfunction
- Levetiracetam – partial and myoclonic, traumatic brain injury, adjust in renal dysfunction
- Oxcarbazepine – no auto-induction, partial, bipolar, causes hyponatremia, some cross sensitivity with carbamazepine. Good for sexual dysfunction.
- Perampanel – neuropsychiatric effects
- Phenobarbital – partial and generalized, not for absence seizures, used for anxiety too.
- Phenytoin – Dose-related effects include nystagmus, ataxia, drowsiness, cognitive impairment. Non-dose related effects include gingival hyperplasia, hirsutism, acne, rash, hepatotoxicity, coarsening of facial features. Therapeutic range: 10-20 mg/ml. Michaelis–Menten saturable kinetics, so dose accordingly.
- Dose titration:
- < 7 mg – increase 100 mg daily
- 7-12 increase 50 mg daily
- > 12 increase by 30 mg or less
- Pregabalin: reduce dose in renal dysfunction
- Valproate: good for absence seizures, migraine and partial complex seizures. Causes neural tube defects, beware in women of childbearing age. Can increase anemia.
- Primidone: Metabolized to phenobarbital. Also used for tremor.
- Tigabin: Use as an adjunct in partial seizures, may cause seizures
- Topiramate: Adjunct for partial seizures or Lennox-Gestault. Warning in open-angle glaucoma.
- Vigabatin: SHARE Rems program. Causes retinal dysfunction.
- Zonisamide: Avoid in sulfa allergy, decreases the ability to sweat, increases kidney stones.
*******No Valproic Acid in potentially pregnant patients***********
Also avoid: phenytoin, carbamazepine, and phenobarbital, but not as severely. Try to use a single agent.
May DC epilepsy meds if:
- Seizure free for at least 2 years on medication
- Single type of partial or primary seizure
- Normal neurological exam and normal IQ
- EGG normal
Drugs that can induce seizures: tramadol, FQs, bupropion, imipenem/cilastatin, benzo withdrawal
Electrolytes that can induce seizures: hyponatremia, hypernatremia, hypercalcemia.
Multiple Sclerosis
Acute Relapses:
- Methylprednisone 1g/day in divided doses for 3-5 days.
- Oral prednisone 1250 mg every other day for 5 days
- Intravenous adrenocortical hormones.
DMARDs-
- Alemtuzumab – Can cause thyroid disorder, infusion reactions, increased infections (screen for herpes and TB before giving), may risk some cancers, vaccinate 6 weeks prior to therapy, avoid live vaccines during treatment.
- B – interferon – flu-like symptoms, injection site problems
- Dimethyl fumarate – GI and skin reactions
- Glatiramer acetate – injection site reactions, chest pain, shortness of breath,
- Fingolimod – Contraindicated in mi, unstable angina and stroke, heart failure class III/ IV monitor for bradycardia, avoid he vaccines.
- mitoxantrone – only second line due to toxicity. Can cause leukemia-like disease
- Natalizumab – relapsing forms, only through special program due to leukoencephalopathy risk.
- Teriflunomide – Secondary, hepatotoxicity, neutropenia, increased infection risk.
Fatigue: non-pharmacologic (rest, sleep management, cooling) or amantadine or methylphenidate
Spasticity: Baclofen or tizanidine
Walking Impairment: Dalfampridine (K+ Channel Blocker): may cause seizures, UTI, insomnia
Pseudobulbar affect: Dextromethorphan/Quinidine
Schizophrenia
Diagnosis:
- Brief Psychiatric Rating Scale (BPRS)
- Positive and Negative Symptom Scale (PANSS) – 7-point, 30 item scale. Requires a 45-minute interview
- Positive Symptom Rating Scale (PSRS) – 1-7 scale
- Brief Negative Symptoms Assessment (BNSA) 1-6 scale
Treatment:
- Antipsychotics are the first line
- The Joint Commission recommends 1 antipsychotic unless:
- 3 failed attempts at monotherapy
- A plan to taper to monotherapy
- Augmentation of clozapine
- Other documentation
Antipsychotics:
- First-generation:
- Mostly treat positive symptoms (hallucinations, delusions, disorganized behavior)
- All lower seizure threshold, cause weight gain, liver toxicity, QT prolongation
- Low potency (anticholinergic > EPS)
- Chlorpromazine (blue-grey skin, also treats hiccups, N/V, RLS) and thioridazine
- High potency (EPS>>anticholinergic)
- Fluphenazine (comes in depot shot), haloperidol (depot too), loxapine (bronchospasm risk), perphenazine, trifluoperazine (don’t give greater than 6 mg/day longer than 12 weeks)
- Smoking may increase metabolism, so may need to decrease dose if patients quits, especially olanzapine and clozapine
- Second Generation (aka atypical):
- Treats mostly positive symptoms, but can improve negative symptoms as well. Cause less extrapyramidal symptoms and tardive dyskinesia. Overall, 2nd generations are better tolerated.
- Some seizure threshold lowering, risk for diabetes and hyperlipidemia, some QT prolongation, hyperprolactinemia, antihistamine effects
- Weight gain worst to least: clozapine > olanzapine > risperidone, paliperidone, iloperidone, quetiapine > ziprasidone, aripiprazole, lurasidone
- Clozapine only for refractory cases due to agranulocytosis risk. Monitor ANC. If <1000, interrupt therapy, if <500 stop.
- May add lamotrigine to clozapine. No data for other anticonvulsants
- Olanzapine should never be taken with lorazepam.
- Risperidone has greater EPS and TD with 6mg or more dosing.
- Ziprasidone has more QT prolongation than others.
- Aripiprazole has more akathisia, low EPS and TD
- Iloperidone causes orthostasis if not properly titrated
- Paliperidone s the active metabolite of risperidone.
- All patients prescribed second-generation antipsychotics should be monitored for weight, blood pressure, fasting, glucose, lipids and waist circumference.
- Benzos may be useful during the acute phase
- Neuroleptic malignant syndrome:
- Can occur with any agent, but more common with high potency first-generation antipsychotics
- Manifested by agitation, confusion, changing levels of consciousness, fever, tachycardia, labile blood pressure, sweating.
- High mortality rate.
- Treatment: Discontinue agent, give supportive therapy including fluids and cooling. Bromocriptine and dantrolene can be used.