Early interventions to prevent posttraumatic stress disorder symptoms in survivors of life-threatening medical events: A systematic review

•Interventions to prevent PTSD symptoms due to terrifying medical events were reviewed.•Interventions were multifaceted and characterized by heterogeneous components.•Acceptability of early intervention was high among ICU, cancer, and cardiac patients.•Some CBT, meaning-making, palliative, and drug interventions reduced PTSD symptoms.•Research is needed to identify optimal PTSD prevention strategies after medical events.