Does the use of surgical face masks reduce postoperative infections in traumatic wounds sutured outside hospital? A randomized study at a Norwegian casualty center

Figures & data

Figure 1. Flowchart of the study.

Table 1. Patient characteristics of 165 patients in the masked (n = 83) and unmasked groups (n = 82).

Patient characteristics	Masked group	Unmasked group	Total
Study participants	83	82	165
Female	25	21	46
Male	58	61	119
Age
<65 years	80	75	155
≥65 years	3	7	10
Medication use	17	29	46
Female	6	11	16
Male	11	18	29
Chronic illnesses	12	20	32
Female	2	9	11
Male	10	11	21

Table 2. Wound characteristics, number of sutures, injury mechanism and time from injury to treatment among 176 wounds in the masked group (n = 88) and the unmasked group (n = 88).

Wound characteristics	Masked group	Unmasked group	Total
Wound location (n = 176)	88	88	176
Head	23	12	35
Elbow/forearm	7	5	12
Wrist/hand	47	59	106
Hip and thigh	2	2	4
Knee and leg	6	9	15
Ankle and foot	3	1	4
Laceration depth (n = 162)
<1.0 cm	61	74	135
≥1.0 cm	18	9	27
Mean depth cm	1.2	1.2	1.2
Laceration length (n = 173)
<3.0 cm	55	57	112
≥3.0 cm	31	30	61
Mean length cm	2.6	2.7	2.7
Number of sutures
Skin (mean) (n = 175)	4.0	4.1	4.1
Subcutaneous (n = 176)	13	5	18
Underlying structures affected (n = 176)	11	12	23
Nail	1	5	6
Bone	0	2	2
Tendon	5	5	10
Nerve	1	1	2
Other (muscle/fascia)	6	0
Time from injury to suture (n = 163)
<3.0 h	60	57	117
≥3.0 h	22	24	46
Range (hours)	0–24	0–18
Injury mechanism
Falling injury	14	12	26
Squeezing and crushing	2	8	10
Contact injury	1	14	3
Cut, stab	49	48	97

Table 3. Postoperative infections (number and percentage) among 176 wounds in the masked group (n = 88) and the unmasked group (n = 88).

	Masked group	Unmasked group	Total
Infection	9 (10.2%)	11 (12.5%)	20 (11.4%) p = .6
Clinical infection	5 (5.7%)	7 (8.0%)	12 (6.8%)
Cellulitis >1 cm	4	6	10, p = .8
Lymphadenitis/lymphangitis	1	1	2, p = 1.00
Fever	0	0	0
Antibiotics after a visit to a doctor due to a wound infection	5^a	4	9^a, p = 1.0

^a One patient in the masked group registered with cellulitis later received antibiotics at a doctor’s visit, and thus registered twice.