That is correct. In fact, most clinics should and do "chart" the details in your medical file (chart). This serves as the permanent record to support the procedure.
The charting should include and disclose the length and width of the strip specimen, which surgical staff was involved inclusive of the techs. What and when the patient was pre-opped, and by who. Vitals are taken and noted in the chart.
The grafts are then segregated as to the graft size (ones, twos, threes, etc) and how many singles, doubles etc were not only harvested from the strip but how many were placed back into the scalp and where placed.
There should be notes denting how many recipient incisions were made, what forms of anasthesia were involved, vascular restrictors employed, method of closure, etc, etc.
The clinic and doctor then at any point in time can pull that chart and know what exactly was done noting any other adverse reactions or occurances.
They also obviously want this information to aide in planning any subsequent procedures and also should be documeting the regrowth progress with telescopic photos over the next 12-18 months post-op.
This is only a sample of what is charted in the patient's medical file.