instruction: what was the first procedure time of patient 41393 for spinal tap until 2103?
response: SELECT procedures_icd.charttime FROM procedures_icd WHERE procedures_icd.icd9_code = (SELECT d_icd_procedures.icd9_code FROM d_icd_procedures WHERE d_icd_procedures.short_title = 'spinal tap') AND procedures_icd.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.subject_id = 41393) AND STRFTIME('%y', procedures_icd.charttime) <= '2103' ORDER BY procedures_icd.charttime LIMIT 1