First, do no harm: balancing the risks and benefits of medical procedures.
D001916:Brachial Artery / Q000601:surgery*; D006801:Humans; D007049:Iatrogenic Disease / Q000517:prevention & control*; D009407:Nerve Block / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D010292:Paresthesia / Q000453:epidemiology / Q000209:etiology; D018962:Phlebotomy / Q000009:adverse effects / Q000592:standards*; D017410:Practice Guidelines as Topic; D011677:Punctures / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D012307:Risk Factors; D020196:Trauma, Nervous System; D014481:United States / Q000453:epidemiology