tell me the name of the organism that was detected in the first catheter tip-iv test of patient 74392?
select microbiologyevents.org_name from microbiologyevents where microbiologyevents.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 74392 ) and microbiologyevents.spec_type_desc = 'catheter tip-iv' and microbiologyevents.org_name is not null order by microbiologyevents.charttime asc limit 1