Table 1. Studies identified from the literature where combination CHG and PVI had been used.
| Year and reference | Publication study type | OEBM level | Population; objective | Method | Outcome measure; result | Comment |
|---|---|---|---|---|---|---|
| 2013 15 a | RCT | N/A | n = 3,715; SSI after total knee arthroplasty | Standard practice (PVI or CHG skin prep) versus standard practice + preoperative CHG wipe 1 h before | Comparative data not available | Given standard practice included either PVI or CHG, the experimental arm would contain examples of patients with a combination PVI and CHG use; unfortunately these data were not available. |
| 2014 16 b | Cohort study | 4 | n = 267; instrumented pediatric spinal surgery | Use of SSI bundle (drawn up based on expert consensus); included preparation with CHG and postoperative PVI | SSI incidence; preoperative bundle: 5.8%, postoperative bundle: 2.2% | Expert consensus was for combination CHG and PVI use. |
| 1994 17 b | RCT | 5 | n = 473; pacemaker insertion | Antibiotics versus no antibiotics (patients had combination CHG/PVI skin preparation) | SSI incidence; no significant difference | Expert consensus was for combination CHG and PVI use. |
| 1986 18 c | Cohort study | 5 | n = 12; hip arthroplasty | Standard practice (CHG bathing on morning of operation and day before) versus standard practice + preoperative PVI iodine rinse after second bath | Bacterial colonization no significant difference reported (individual data not shown) | Results suggest that a combination of PVI and CHG was not better than CHG alone. |
| 2001 29 b | RCT | 5 | n = 50; foot or ankle surgery | Standard preparation (PVI + CHG) versus standard preparation + scrub with gauze-soaked swab | Bacterial colonization; standard preparation: 20.8%, additional scrub: 7.7% | Expert consensus was for combination CHG and PVI use. |
| 2010 19 b | Cohort study | 5 | n = 126; patients with DM undergoing foot or ankle surgery | Ulcerated versus nonulcerated standard preparation; PVI + CHG | Bacterial colonization; no significant difference | Expert consensus was for combination CHG and PVI use. |
| 2012 20 b | Letter | 5 | Plastic surgery | N/A | N/A | Expert opinion was for combination CHG and PVI use. |
| 1971 30 b | Cohort study | 5 | n = 76; general surgery | CHG versus PVI + CHG | Bacterial colonization; PVI + CHG: 70% sterile, CHG: 36% sterile | Use of CHG + PVI was more effective at sterilization than CHG alone for decolonization. |
| 2013 23 b | Quality improvement study | 5 | Spinal surgery | Bundle versus no bundle; bundle included CHG preparation, intraoperative irrigation with PVI | SSI incidence; preoperative bundle: 10.2%, postoperative bundle: 3.1% | Expert consensus was for combination CHG and PVI use. |
| 2007 22 b | Quality improvement study | 5 | Pain medicine | Bundle versus no bundle; bundle required skin preparation with CHG + PVI | SSI incidence; nonsignificant reduction following introduction of bundle | Expert consensus was for combination CHG and PVI use. |
| 2014 21 b | RCT | 5 | n = 1,874; arthroplasty or spinal fusion | Nasal decolonization; CHG + nasal mupirocin versus CHG + PVI | SSI incidence; CHG/mupirocin: 1.6%, CHG/PVI: 0.7% | Although not considering the operative site, this would suggest that a combination of CHG + PVI was better than CHG alone for decolonization of the nasal mucosa. |
| 2002 27 b | RCT | 5 | n = 49; foot and ankle | Standard preparation (home CHG scrub + preoperative PVI) versus standard preparation + additional preoperative alcohol scrub | Bacterial colonization; CHG/PVI: 35%, CHG/PVI/alcohol: 57% | Data are not easily applied to our study outcomes, other than the fact a combination of CHG and PVI was clearly desired by the study authors. |
| 2001 28 b | Cohort study | 5 | n = 1,038; neurosurgery | Head shaving versus no head shaving but CHG hair wash; standard preparation = CHG + PVI | SSI incidence; head shave: 1.2%, no head shave: 1.3% | Expert consensus was for combination CHG and PVI use. |
| 2015 26 b | RCT | 2 | n = 1,394; obstetrics and gynecology | PVI versus CHG versus CHG + PVI | SSI incidence; overall no significant difference, but in obese women, combination significantly better | Combination was more effective in high-risk group. |
| 1991 25 b | Cohort study | 5 | n = 242; cadaveric skin transplant harvest | PVI versus PVI + CHG | Bacterial colonization; PVI: 13.7%, CHG + PVI: 5.6% | Use of CHG + PVI was better than PVI alone for decolonization. |
| 2009 24 b | Clinical trial | 5 | RCT n = 100; neurosurgery | CHG versus PVI + CHG | Bacterial colonization; CHG: 14%, CHG + PVI: 0% | Use of CHG + PVI was more effective at sterilization than CHG alone for decolonization. |
| 2004 1 b | RCT | 5 | n = 140; ICU central line insertion | PVI versus CHG versus PVI + CHG | Bacterial colonization; PVI: 30.8%, CHG: 20.4%, CHG + PVI: 4.7% | Although not specifically for surgery, preprocedural antisepsis with a combination of CHG and PVI was more effective than either agent on its own for decolonization. |
| 2010 11 b | Comparative study | 5 | In vitro/ex vivo (porcine) | PVI versus CHG versus PVI + CHG | Bacterial colonization; PVI, CHG, CHG + PVI: best | Although not a clinical study, this study provides evidence of the greater bactericidal effect of combination CHG and PVI. |
Abbreviations: CHG, chlorhexidine; DM, diabetes mellitus; ICU, intensive care unit; N/A, not applicable; OEBM, Oxford Levels of Evidence-Based Medicine; PVI, povidone-iodine; RCT, randomized controlled trial; SSI, surgical site infection.
Note: The Oxford Evidence Based Medicine levels 1 to 5, where 1 is high quality evidence and 5 is low quality, have been used to consider the study in relation to our primary objective; does combination CHG and PVI reduce SSI?
a
Evidence is unequivocal or unable to comment.
b
Results support combination CHG and PVI.
c
Results refute combination CHG and PVI.