ABPN C-L Psychiatry cheat sheet

Delirium requires acute onset with fluctuation plus inattention, and either disorganized thinking or altered level of consciousness (CAM algorithm); the hypoactive subtype is the most frequently missed.

New psychiatric symptoms in the medically ill warrant CBC, comprehensive metabolic panel, TSH, B12, syphilis and HIV testing, urinalysis, urine drug screen, and ECG before attributing symptoms to a primary psychiatric disorder.

Medical mimics of anxiety include hypoxia, hypoglycemia, hyperthyroidism, pheochromocytoma, arrhythmia, and substance withdrawal; panic disorder is not diagnosed when symptoms occur only in the context of a medical illness.

Cognitive screening: the MMSE is education- and language-sensitive, while the MoCA is more sensitive for mild cognitive impairment and executive dysfunction; both are cross-sectional and do not replace longitudinal history.

Serotonin syndrome: clonus, hyperreflexia, mydriasis, diarrhea, and agitation within hours. Neuroleptic malignant syndrome: lead-pipe rigidity, bradyreflexia, elevated CK, leukocytosis, and hyperthermia over days after dopamine antagonists.

Secondary mania: consider corticosteroids, hyperthyroidism, HIV, neurosyphilis, multiple sclerosis, and right frontal or limbic stroke; first onset after age 40 without family history favors a secondary cause.

The Bush-Francis Catatonia Rating Scale is the standard screening instrument; a lorazepam challenge of 1-2 mg with rapid improvement supports the diagnosis and predicts treatment response.

Depression screening in medical illness emphasizes cognitive-affective items (anhedonia, guilt, hopelessness, suicidality) because neurovegetative symptoms overlap heavily with the underlying medical condition.

Triage requests by risk: active agitation, suicidal or violent ideation, delirium with safety risk, urgent capacity decisions, and active withdrawal come first; elective capacity and adjustment questions can be scheduled.

Clarify the specific clinical question with the referring team before chart review; recommendations that answer a different question than the one asked are a common cause of nonadherence.

Document the reason for consultation, relevant history, risk assessment, capacity determination and its basis, recommendations, and follow-up plan; verbal high-risk recommendations should be confirmed in the note.

Curbside advice given without record review or examination carries limited accuracy; convert to a formal consultation when the question involves risk, capacity, or complex psychopharmacology.

Use closed-loop communication: have the referring clinician repeat back medication and safety recommendations, especially during handoffs and interfacility transfers.

42 CFR Part 2 protects substance use disorder treatment records more strictly than HIPAA and requires specific written consent for most disclosures, including to other treating clinicians.

Multicomponent delirium prevention (orientation, sleep hygiene, early mobility, hydration, sensory aids, family involvement) reduces incidence and is a core CL systems-level intervention.

Reimbursement for consultation-liaison work is time-based; documenting total time and the complexity of the evaluation supports coding for extended and care-coordination services.

Lithium is renally eliminated: reduce or avoid in chronic kidney disease, target levels of 0.6-1.2 mEq/L, and watch for toxicity precipitated by dehydration, NSAIDs, ACE inhibitors, ARBs, and thiazides.

Hepatic impairment: prefer low-dose sertraline or citalopram; avoid valproate (hepatotoxicity, hyperammonemia, pancreatitis) and nefazodone; reduce doses of drugs with extensive first-pass metabolism.

Renal impairment: avoid lithium and meperidine (normeperidine accumulation lowers seizure threshold); dose-adjust gabapentin, pregabalin, and most antipsychotics; lithium and valproate are dialyzable.

QT risk: intravenous haloperidol, ziprasidone, thioridazine, and citalopram above 40 mg/day; obtain ECG, correct potassium and magnesium, and avoid combining QT-prolonging agents in cardiac patients.

CYP2D6 inhibitors (fluoxetine, paroxetine, bupropion, duloxetine) raise risperidone, aripiprazole, tricyclic, and tamoxifen metabolite levels; they also block conversion of codeine and tramadol to active analgesics.

Clozapine requires REMS monitoring for agranulocytosis and carries risks of myocarditis (first two months), seizure, constipation with ileus, and orthostatic hypotension; cigarette smoking lowers serum levels.

ECT is effective in pregnancy, in older adults, and in catatonia; assess cardiac risk and intracranial pressure first, and consider reducing lithium to limit prolonged seizures and postictal confusion.

MAOIs combined with sympathomimetics or tyramine cause hypertensive crisis; avoid concurrent meperidine, tramadol, linezolid, and methylene blue because of serotonin toxicity.

Nonpharmacologic measures are first-line for delirium; antipsychotics reduce agitation but do not shorten delirium or improve cognition and carry QT and mortality risk in older adults.

Benzodiazepines are indicated for alcohol or benzodiazepine withdrawal and for catatonia; they generally worsen delirium from other causes and should be avoided in those cases.

Capacity requires four abilities: understanding, appreciation, reasoning, and expressing a choice; capacity is decision-specific and can fluctuate, so reassess when the clinical state changes.

Suicide risk assessment covers ideation, intent, plan, means, prior attempts, substance use, and protective factors; no-suicide contracts are not evidence-based and are replaced by collaborative safety planning.

Agitation: treat the underlying cause (hypoglycemia, hypoxia, pain, urinary retention, withdrawal, delirium) and use verbal de-escalation before medication or restraint; restraint is a last resort with continuous monitoring.

Catatonia: lorazepam challenge first; malignant catatonia with fever, autonomic instability, and elevated CK requires high-dose benzodiazepines and early ECT.

ICU delirium is common and detected with the CAM-ICU or ICDSC; the ABCDEF bundle (pain, awakening and breathing trials, sedation choice, delirium monitoring, mobility, family) reduces delirium and length of stay.

Transplant evaluation assesses adherence, substance use, social support, psychiatric stability, and decisional capacity; active untreated psychosis and ongoing substance use are relative contraindications.

Alcohol withdrawal: symptom-triggered benzodiazepines guided by CIWA-Ar; give thiamine before glucose; lorazepam is preferred in liver disease; delirium tremens requires ICU-level monitoring and has substantial mortality untreated.

Opioid overdose: titrate naloxone to restore respiration rather than full arousal; its half-life is shorter than most opioids, so monitor for renarcotization and consider an infusion.

Buprenorphine is a partial mu agonist with a ceiling on respiratory depression; it precipitates withdrawal if started while full agonists are present, and low-dose induction protocols exist for transitioning patients.

Equianalgesic conversion: calculate the new dose, reduce by 25-50% for incomplete cross-tolerance, then reassess; methadone and transdermal fentanyl conversions are nonlinear and error-prone.

CYP2D6 inhibitors block codeine and tramadol analgesia; ultrarapid metabolizers risk opioid toxicity; codeine and tramadol are avoided in breastfeeding and after pediatric tonsillectomy.

Palliative dyspnea: low-dose opioids treat air hunger; oxygen helps only hypoxemic patients; benzodiazepines and a cool air fan address the anxiety component of breathlessness.

Terminal delirium and pain crisis may require proportional palliative sedation; distinguish this from euthanasia and document goals-of-care discussions with the patient and family.

Benzodiazepine taper: reduce by roughly 10-25% every two to four weeks to limit withdrawal seizures; abrupt discontinuation after long-term use is dangerous.

Valproate in pregnancy carries neural tube defect and dose-dependent neurodevelopmental risk; avoid when possible, and when unavoidable use the lowest effective dose with folate and reliable contraception.

Lithium in pregnancy is associated with a small increase in Ebstein anomaly; abrupt discontinuation raises relapse risk, so taper or adjust only with obstetric and psychiatric coordination.

SSRIs are the preferred antidepressants in pregnancy; sertraline is generally preferred during breastfeeding because of low milk transfer, and paroxetine has been linked to cardiac defects.

Postpartum psychosis is a psychiatric emergency, usually beginning within two weeks of delivery; treat with antipsychotics or lithium and hospitalize with explicit infant safety planning.

Screen for perinatal depression with the Edinburgh Postnatal Depression Scale; a score of 10 or more, or any endorsement of the self-harm item, prompts clinical assessment.

Geriatric prescribing: follow Beers criteria, start low and go slow, minimize anticholinergics and benzodiazepines, and review for falls, delirium, and drug interactions.

Adjustment disorder: symptoms begin within three months of an identifiable stressor, cause impairment, do not meet criteria for another disorder, and resolve within six months after the stressor ends.

Acute trauma: benzodiazepines are not recommended for PTSD prevention; trauma-focused psychotherapy is first-line, and motivational interviewing improves adherence in chronic medical illness.