Several other possibilities:

duration of surgical procedure
procedure duration
duration of operation
etc

[DOC] Missouri Healthcare-Associated Infection Reporting System (MHIRS)File Format: Microsoft Word - View as HTML
That is, add the duration of operation for both procedures. ... combined duration of all procedures, which should be the time from skin incision to closure. ...
www.dhss.mo.gov/MHIRS/SSIFinalVersion.doc - Similar pages


Effects of a thin-sized lead body of a transvenous single coil ...The total procedure duration spanned skin incision to closure. The incidence of lead repositioning during the lead implantation time and during ventricular ...
www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve& db=PubMed&list_uids=11060866&dopt=Abstract - Similar pages


CHEST: Perioperative risk factors for anastomotic leakage after ...Perioperative data studied were the duration of surgical procedure (from skin incision to closure), the duration of one-lung ventilation (OLV), ...
www.findarticles.com/p/articles/ mi_m0984/is_5_128/ai_n15967335 - 37k





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Note added at 58 mins (2006-03-22 17:47:37 GMT)
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operating time
operative duration

UroToday - Conference Reports - Conference Reports... duration of hospitalization, percent of patients discharged in less than 1 day ... The mean operating time was 163 minutes (incision to closure) for RRP ...
www.urotoday.com/prod/contents/confreport/ article.asp?cat=confReport&sid=184&tid=339&aid=1072 - 79k - Cached - Similar pages


Blackwell Synergy: BJU Int, Vol 90, Issue 9, pp. 876-882 ...The operative duration (the time from first incision to closure of the last wound) was recorded. Postoperative analgesia consisted of intravenous morphine ...
dx.doi.org/10.1046/j.1464-410X.2002.03049.x

But all in all, I think "incision to closure time" is best since it's quite specific (as is the source).