Key Concepts
Overview
Major depressive disorder ties high-yield nursing judgment to airway, perfusion, infection control, and safe medication administration. MDD is a syndrome of depressed mood or anhedonia plus neurovegetative signs lasting ≥2 weeks causing dysfunction. The SIGECAPS mnemonic maps screening domains: Sleep change, Interest loss, Guilt/worthlessness, Energy loss, Concentration impairment, Appetite/weight change, Psychomotor change, Suicidality. Nursing performs safety screening (ideation, plan, intent, means, protective factors), substance use assessment, medical mimics (hypothyroid, B12 deficiency, OSA), and perinatal specificity. Therapies include SSRIs/SNRIs, psychotherapy, ECT for severe catatonia/suicidality, and ketamine/esketamine pathways in select systems. Black box: young adults may have activation/akathisia early after SSRI start—teach to report restlessness, impulsivity, or worsening mood especially in the first weeks. Cross-link US RN lessons hub · Canada RN lessons hub and related LESSON cards where the stem crosses systems. Pathophysiology in plain language. Think in layers: cells → organs → whole-person compensation. When a stem describes acute change (fever, pain, new neuro deficit, hypoxia, hypotension), ask what system is failing to compensate and what reversible threat is most time-sensitive. Nurses are the continuity layer: you trend objective data,...