TABLE 2.

Perioperative COVID-19 in Eligible Patients Before and After Implementation of Routine Preoperative Screening

	No. (%)
	Ad Hoc Testing	Routine Screening	Total Study Period
	(March 15–April 5)	(April 6–May 15)	(March 15–May 15)
	(n = 257)	(n = 273)	(n = 530)
Not tested preop / Eligible	233/257 (90.7)	6/273 (2.2)	227/530 (42.8)
Postop + / Preop –	7/221 (3.2)	0/7 (0.0)∗	7/228 (3.1)
Tested 1–3 days preop / Eligible	15/257 (5.8)	97/273 (35.5)	112/530 (21.1)
Postop + / Preop –	2/14 (14.3)	0/89 (0.0)	2/103 (1.9)
Tested same day preop / Eligible	9/257 (3.5)	170/273 (62.3)	179/530 (33.8)
Postop + / Preop –	0/8 (0.0)	0/162 (0.0)	0/170 (0.0)
Total postop + / Total preop –	9/243 (3.7)†	0/258 (0.0)†	9/501 (1.8)

Eligibility for screening was defined as absence of positive testing >3 d preoperatively. There were 12 presumed preoperative positive cases, as determined by 2 or more CDC symptoms of COVID-19, all of which occurred before implementation of routine preoperative screening. In practice, all postoperative positive patients were confirmed by SARS-CoV-2 PCR testing.

^∗One patient was tested on the day of surgery but had an invalid specimen; the patient tested negative on repeat postoperative day 1 and was presumed preoperative negative.

^†OR: 0.048, 95% CI: 0.003–0.825, P = 0.036.

CDC indicates Centers for Disease Control and Prevention; COVID-19, coronavirus disease 2019.