Critical Care Aggression and Violence Events (CAVE) Against Nurses in the ICU: Epidemiology and Risk Factors for Recurrence

OBJECTIVES: To quantify and characterize aggression and violence against nurses, identify associated clinical characteristics, evaluate measures in response, and explore predictors of recurrent incidents in the ICU. DESIGN: Retrospective single-center study. Incidence and characteristics of aggression and violence against ICU nurses were the primary outcomes. Aggression was defined as hostile behavior or resistance to care without intent to harm. Violence comprised verbal, physical, or sexual acts to threaten or inflict harm. Secondary outcomes included risk factors for recurrent incidents, defined as multiple episodes of aggression/violence separated by greater than or equal to 24 hours. Multivariable analyses were performed to identify potential independent associations. SETTING: Data were collected from 2023 to 2024 at the tertiary medical-surgical ICU with up to 35 beds at the University Hospital Basel. Nursing operations followed a three-shift system: day (07:00-15:00), late (15:00-23:00), and night (23:30-07:00). SUBJECTS: Clinical reports from ICU nurses were screened. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: During 2190 shifts, 308 aggressive or violence incidents (14% of shifts) were reported. Most occurred during late (37%) or night (34%) shifts; 75% involved violence. Violent incidents were combined in nature (79% physical, 43% verbal, and 3% sexual). Patients were mainly involved (97%) and predominantly male (71%; median age 67; 90% emergency admissions). Psychiatric comorbidities, drug, and alcohol abuse were found in 20-33%. Recurrent aggression/violence occurred in 27%, predicted by longer ICU stay (adjusted odds ratio [OR] = 1.05/every additional hour), aggression as the first incident (adjusted OR = 6.9), and verbal violence as the first incident (adjusted OR = 4.3). Nurses (89%, two-thirds female, median 7 yr' experience) rarely documented harm (1.3%), but patients were reported to suffer complications in 60% of incidents, mainly from oversedation and physical harm from restraints. CONCLUSIONS: Violence in the ICU is frequent and almost always caused by patients. Recurring violence was independently associated with longer ICU stay, initial aggression, and verbal violence. Staff harm was rare, but incidents were frequently associated with complications in patients.