There isn't really a direct translation of "atendimento", so I would change the phrase around a bit to make it sound natural in English.

[There is also um ambulatório cirúrgico] ... which, on average, sees 2000 patients per week.

"to see a patient" is the usual away of referring to "atendimentos" in English.
HTH

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Note added at 23 mins (2007-11-11 16:31:25 GMT)
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OR also possible

***treats*** 2000 patients per week.

proposal | nurseseyesite.nhs.uk
Average Number Of Patients Seen Per Clinic: The following table shows that the average number of extra patients in clinic during the period was 7.3 patients ...
www.nurseseyesite.nhs.uk/ spec_area_pcare/np_proposald.asp

The NHS performance guide 1995-96
Definition: For each unit this is the number of patients seen and assessed by a medically qualified person within 5 minutes of their arrival at the A&E ...
www.performance.doh.gov.uk/nhsp96/stats.htm

[PDF]
My attempt at plain English descriptions of the putative PTL ...
File Format: PDF/Adobe Acrobat - View as HTML
Number of patients treated in the last seven days that were not within the target time. 5. Number of patients treated in the last seven days within the ...
www.regulator-nhsft.gov.uk/ documents/050805_DH_PTLguidanceFINAL.pdf