Patient Safety Issues CHLORHEXIDINE BATHING AND MICROBIAL CONTAMINATION IN PATIENTS BATH BASINS By Jan Powers, RN, PhD, Jennifer Peed, RN, BSN, Lindsey Burns, RN, BSN, and Mary Ziemba-Davis, BA C N E 1.0 Hour tice to CNE enrollees: A closed-book, multiple-choice examination following this article tests your under standing of the following objectives: 1. Compare the rate of bacterial contamination on bath basins using soap to those basins where a standardized chlorhexidine solution is used for bathing. 2. List 3 common organisms found in patients bath basins. 3. Describe how basin, device, infection control, and isolation variables affect culture results when using chlorhexidine for patient baths. To read this article and take the CNE test online, visit www.ajcconline.org and click CNE Articles in This Issue. test fee for AACN members. 2012 American Association of Critical-Care Nurses doi: http://dx.doi.org/10.4037/ajcc2012242 Background Research has demonstrated the hazards associated with patients bath basins and microbial contamination. In a previous study, soap and water bath basins in 3 acute care hospitals were found to be reservoirs for bacteria and potentially associated with the development of hospital-acquired infections. Bacteria grew in 98% of the basin samples; the most common were enterococci (54%), and 32% were gram-negative organisms. Objective To assess the presence of bacterial contaminants in wash basins when chlorhexidine gluconate solution is used in place of standard soap and water to wash patients. Methods Bathing with chlorhexidine gluconate is the standard of practice for all patients in intensive care units at St Vincent Hospital. Specimens from 90 bath basins used for 5 days or more were cultured for bacterial to assess contamination of basins when chlorhexidine gluconate is used. Results Of the 90 basins cultured, only 4 came back positive for microbial ; all 4 showed of gram-positive organisms. Three of the 4 organisms were identified as coagulase-negative staphylococcus, which is frequently found on the skin. This translates into a 95.5% reduction in bacterial when chlorhexidine gluconate is used as compared with soap and water in the previous study (Fisher exact test, P <.001). The only factor that was related to positive cultures of samples from basins was the sex of the patient. Discussion Compared with the previous study examining microbial contamination of basins when soap and water was used to bathe patients, bacterial in patients bath basins decreased significantly with the use of chlorhexidine gluconate, drastically reducing the risk for hospital-acquired infections. Such reduced risk is especially important for critically ill patients at high risk for bacterial infection. (American Journal of Critical Care. 2012;21:338-343) 338 AJCC AMERICAN JOURNAL OF CRITICAL CARE, September 2012, Volume 21,. 5 www.ajcconline.org
Patients bath basins in hospitals are a known source of microbial contamination. 1,2 In a previous study, 1 bath basins from which samples were cultured in 3 acute care hospitals were found to be reservoirs for bacteria and potentially associated with the development of hospital-acquired infections. Bacteria grew in 98% of the basin samples, with the most prominent being enterococci (54%) and gram-negative organisms (32%). 1 More alarming in this study was the association between microbes found in the bath basins and infection of patients. Based on this and other studies of microbial contamination of patients bath basins, 2 a change in practice eliminating the use of bath basins for hygiene in hospitalized patients would be warranted. However, it is not yet known whether bacterial contaminants are present in patients bath basins when chlor hexidine gluconate (CHG) solution is used for bathing. It is known that bathing with CHG decreases the frequency of infections with vancomycin-resistant enterococcus and methicillin-resistant Staphylococcus aureus 3-8 and bloodstream infections. 8-11 Research studies showing the effectiveness of CHG bathing in the reduction of hospital-acquired infections have not clearly delineated which preparation of CHG (impregnated cloths vs CHG solution diluted in bath water) is most effective. Based on previous studies, standard practice in our intensive care unit (ICU) is bathing of all patients with 2 fl oz (60 ml) of 4% CHG solution diluted in 3 qt (2.85 L) of water. The purpose of this study was to assess the presence of bacterial contaminants in wash basins when CHG solution is used in place of standard soap and water to wash patients. Methods Bathing Procedure Before the start of the study, standardized procedures for patient hygiene and storage of wash basins were in place. ICU nurses bathe patients with 2 fl oz (60 ml) CHG to 3 qt (2.85 L) water in bath About the Authors Jan Powers is director of clinical nurse specialists and a clinical nurse specialist in the trauma intensive care unit at St Vincent Hospital in Indianapolis, Indiana. Jennifer Peed and Lindsey Burns are staff nurses in the medical intensive care unit at St Vincent Hospital. Mary Ziemba- Davis is a research scientist on the clinical nurse specialist team at St Vincent Hospital. Corresponding author: Jan Powers, RN, PhD, Director of Clinical Nurse Specialists and Nursing Research, Trauma Intensive Care Unit Clinical Nurse Specialist, St Vincent Hospital, 2001 West 86th Street, Indianapolis, Indiana 46260 (e-mail: jmpowers@stvincent.org). basins, using a new washcloth for each body part bathed. Initial bathing occurs within 6 hours of ICU admission and daily thereafter. After completion of bathing, basins are wiped with a paper towel to eliminate standing water and then placed upside down on a storage table to air dry. Basins are labeled and designated solely for CHG bathing and are discarded if contamination with vomit or other bodily fluids occurs. An additional basin is labeled for the storage of bath supplies. Study Procedure Samples from 90 basins used to wash 90 patients in a 40-bed mixed medical surgical ICU at a large Midwestern tertiary care hospital (St Vincent Hospital, Indianapolis, Indiana) were cultured for microbial contamination. Study enrollment continued until a sample of 90 basins was achieved. All bath basins were dated when the patient was admitted to the ICU, and only basins that had been in use for 5 days were included in the sample. Approval was obtained from the institutional review board before the start of the study. Once enrolled, bath basins were assigned a unique identification number to ensure that basin duplication did not occur. A data tracking sheet was completed, with the data being entered into a Microsoft Excel spreadsheet by a trained investigator. The data collection tool recorded: Patients demographics: sex, medical vs surgical admission diagnosis, age, length of stay in the hospital, and length of stay in the ICU; Basin variables: the number of days that basins had been in use when the culture samples were obtained and the number of days since the patient s last bath when the basins were sampled; Device variables: presence of central catheters, arterial catheters, peripherally inserted central catheters, endotracheal tubes, tracheostomy tubes, ventilators, urinary catheters, and fecal containment devices; Patients hospital bath basins are a known source of microbial contamination. www.ajcconline.org AJCC AMERICAN JOURNAL OF CRITICAL CARE, September 2012, Volume 21,. 5 339
Table 1 Bath basin study comparisons a Cleaning agent used Chlorhexidine (current study) Soap and water (Johnson et al., 2009) 1 a Fisher exact test: P <.001. The intensive care unit has standardized procedures for patient hygiene and storage of wash basins. Bacterial 4 (4.4) 90 (97.8). (%) of patients bacterial 86 (95.6) 2 (2.2) Infection and isolation variables: Infection(s) at latest laboratory culture (yes vs no), antibiotics (yes vs no), and isolation (yes vs no). Basin Cultures Basins were allowed time to dry thoroughly before samples were obtained for culture. A culture swab for each study basin was obtained from the hospital laboratory. The culture swab was saturated with sterile saline before culture and rolled along the bottom of the basin perimeter around all corners and sides in a continuous motion. The swab was then rolled along the center of the basin. A laboratory requisition form was completed by using identification numbers for each study patient/bath basin that were known only to the first author. Swab specimens labeled with the same identifier were submitted for analysis. Laboratory findings were entered into the Excel spreadsheet and filed in regulatory study binders. Statistical Analysis Univariate tests rather than logistic regression were used to assess the extent to which independent variables were predictive of bacterial on basins because of the small number of observed bacterial events compared with the number of nonevents. Pearson χ 2 tests were used for all nominal variable comparisons with a Fisher exact test applied to all 2 2 tables. The nonparametric 2-sample Wilcoxon rank sum test for median differences was used in place of 2 independent sample t tests for mean differences. Mintab Version 15 was used for statistical analysis with an α of.05 or less as the criterion for statistically significant differences. P values adjusted for ties are reported for 2-sample Wilcoxon rank sum tests. Results Ninety bath basins from ICU patients were examined, 42 from female (46.7%) and 48 (53.3%) from male patients. Patients were from 24 to 88 years old (mean, 61.6 years; SD, 14.0 years). Mean lengths of stay in the hospital and in the ICU were 11.1 (SD, 7.1; range, 5-41) days and 9.8 (SD, 6.6; range, 4-42) days, respectively. Eighty-two percent of patients (n = 74) were admitted to the ICU for medical diagnoses and 18% (n = 16) were postsurgical patients. Of the 90 bath basins cultured, only 4 (4.4%) were positive for microbial. All microbes were gram-positive organisms, with 3 identified as coagulase-negative staphylococcus, which is frequently found on the skin. One culture yielded grampositive cocci. The median number of days that basins had been in use when they were cultured did not differ between basins that showed bacterial (median, days) and basins that showed no bacterial (median, 7.0 days; W = 3879.5; P =.51). Median days since patients last baths with the study basins were equivalent for basins that showed bacterial (median = 1.0 day) and basins that showed no bacterial (median = 1.0 days; W = 3906.5; P =.90). Table 1 compares bacterial of samples from bath basins in the current study with CHG to the existing basin study 1 in which soap and water were used to bathe patients. A 95.5% reduction in basin cultures positive for bacteria was observed when CHG was used (4.4% vs 97.8% ; Fisher exact test, P <.001). Relationships between patients demographics, device variables, infection and isolation variables, and bacterial in study basins are presented in Table 2. The only significant main effect was between the patient s sex and bacterial. All basins positive for bacterial were associated with female patients (Fisher exact test, P =.04). ne of the other independent variables were significantly related to bacterial in study basins. Discussion In dramatic contrast to an existing study 1 that showed 97.8% bacterial in 92 bath basins when soap and water was used to bathe patients, we observed 4.4% bacterial in 90 basins when CHG solution was used for patients baths. Our finding reflects a 95.5% reduction in cultures of bath basins positive for bacteria, indicating that patient bath basins may not be inevitable sources of bacterial when CHG is used. The patient s sex was the only factor that was associated with positive cultures; other patients characteristics, length of basin use, the presence of indwelling devices, identified infections, antibiotic use, and isolation status were not related to positive culture results. 340 AJCC AMERICAN JOURNAL OF CRITICAL CARE, September 2012, Volume 21,. 5 www.ajcconline.org
Table 2 Bacterial in bath basins by patient, device, and infection/isolation characteristics. (%) of patients a Characteristic Bacterial bacterial P b Sex Female Male Diagnosis Medical Surgical Age, median, y Length of stay, median, d In hospital In intensive care unit Central catheter Arterial catheter Peripherally inserted central catheter Endotracheal tube Tracheostomy tube Ventilator Foley catheter Fecal containment device Infection shown by latest culture Antibiotics Isolation 68.0 2 (50) 2 (50) a Units for age and length of stay are as specified in first column; all other values are. (%) of patients. b Most P values based on Fisher exact test, unless W value indicated in footnote. c Wilcoxon rank sum test, W = 3888.5. d Wilcoxon rank sum test, W = 3960.5. e Wilcoxon rank sum test, W = 3922.0. 38 (44.2) 48 (55.8) 71 (82.6) 15 (17.4) 60.5 9.0 43 (50) 43 (50) 12 (14.0) 74 (86.0) 47 (54.7) 39 (45.3) 45 (52.3) 41 (47.7) 20 (22.2) 70 (77.8) 52 (60.5) 34 (39.5) 76 (88.4) 10 (11.6) 16 (18.6) 70 (81.4) 52 (60.5) 34 (39.5) 65 (75.6) 21 (24.4) 20 (23.3) 66 (76.7).04.55.64 c.36 d.87 e.62.47.62.27 Our study was limited to 90 CHG bath basins by design to make accurate comparison to the 92 soap and water bath basins cultured by Johnson et al. 1 Like Johnson et al, basins in the current study were sampled from a medical/surgical ICU. Unlike the study by Johnson et al, our study did not include www.ajcconline.org AJCC AMERICAN JOURNAL OF CRITICAL CARE, September 2012, Volume 21,. 5 341
Patients bath basins may not be inevitable sources of bacterial when chlorhexidine is used. It may be premature to conclude that bath basins are a potential source of hospitalacquired infections. basins from a cardiac ICU and rehabilitation unit, which potentially limits the comparability and generalizability of our findings. It is relevant to note, however, that infection-control bathing practices and care and storage of bath basins were standardized throughout the study ICU. We cannot rule out that potential differences in bathing practices and basin care and storage techniques alone account for disparities in bacterial contamination in these 2 studies. Although universal precautions were followed, bathing methods were not observed in the comparison study, and basin care and storage were highlighted as a potentially significant source of the high rate of basin bacterial contamination. 1 In our study, we had already implemented standardized bathing practices along with the implementation of CHG bathing. It is therefore unknown whether it was our standardized techniques for bathing patients and for care of wash basins or the CHG in the basin that made the significant difference in microbial contamination. Additionally, the current study is limited by the lack of a control group; multisite research with a control group controlling for bathing and basin storage techniques is recommended to resolve this important question. Evidence has established that hospital tap water is a source of bacterial contamination. 12 In a systematic review of 18 randomized controlled trials, experimental studies, and meta-analyses conducted since 2006, researchers concluded that CHG bathing is acceptable and useful for the reduction of central catheter associated bloodstream infections, the acquisition or decolonization of multidrug-resistant organisms, and surgical site infections. 13 On the evidence grading scale used, CHG bathing was supported by fair to good evidence, with the weight of the evidence and expert opinion not strongly in favor. 13 It is unknown whether efficacy is improved with the use of CHG-impregnated cloths versus liquid CHG solution in bath water, which remains an area for future research. Establishment of evidencebased bathing procedures for hospitalized patients is required to ensure best practice and potentially reduce the incidence of nosocomial infections. Our findings of minimal microbial contamination of bath basins when CHG is used to bathe patients suggest that it may be premature to conclude that bath basins are a potential source of hospital-acquired infections. FINANCIAL DISCLOSURES ne reported. eletters w that you ve read the article, create or contribute to an online discussion on this topic. Visit www.ajcconline.org and click Submit a response in either the full-text or PDF view of the article. REFERENCES 1. Johnson D, Lineweaver L, Maze L. Patients bath basins as potential sources of infection: a multicenter sampling study. Am J Crit Care. 2009;18:31-40. 2. Marchaim D, Abreu-Lanfranco O, Taylor AR, et al. Hospital bath basins are frequently contaminated with multi-drug resistant human pathogens. Poster presented as part of the 40th Annual Critical Care Congress of the Society of Critical Care Medicine, January 15-19, 2011, San Diego, California. http://www.sageproducts.com/documents/pdf/education /symposia/skin/21529_marchaim_shea_poster.pdf. Accessed June 8, 2012. 3. Batra R, Cooper B, Whiteley C, et al. Efficacy and limitation of a chlorhexidine-based decolonization strategy in preventing transmission of methicillin-resistant Staphylococcus aureus in an intensive care unit. Clin Infect Dis. 2010;50:210-217. 4. Ridenour G, Lampen R, Pederspiel J, et al. Selective use of intranasal mupirocin and chlorhexidine bathing and the incidence of methicillin-resistant Staphylococcus aureus colonization and infection among intensive care unit patients. Infect Control Hosp Epidemiol. 2007;28:1155-1161. 5. Sandri A, Dalarosa M, Ruschel de Alcantara L, et al. Reduction in incidence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection in an intensive care unit: role of treatment with mupirocin ointment and chlorhexidine baths for nasal carriers of MRSA. Infection Control Hosp Epidemiol. 2006;27:185-187. 6. Vernon M, Kayden M, Trick W, et al. Chlorhexidine gluconate to cleanse patients in a medical intensive care unit: the effectiveness of source control to reduce the bioburden of vancomycin-resistant enterococci. Arch Intern Med. 2006; 166:306-312. 7. Kassakian SZ, Mermel LA, Jefferson JA, Parenteau SL, Machan JT. Impact of chlorhexidine bathing on hospitalacquired infections among general medical patients. Infect Control Hosp Epidemiol. 2011;32:238-243. 8. Climo M, Sepkowitz K, Zuccotti G, et al. The effect of daily bathing with chlorhexidine on the acquisition of methicillinresistant Staphylococcus aureus, vancomycin-resistant enterococcus, and healthcare-associated bloodstream infection: results of a quasi-experimental multicenter trial. Crit Care Med. 2009;37:1858-1865. 9. Bleasdale S, Trick W, Gonzalez I, et al. Effectiveness of chlorhexidine bathing to reduce catheter associated bloodstream infections in medical intensive care unit patients. Arch Intern Med. 2007;167(19):2073-2079. 10. Munoz-Price L, Hota B, Stemer A, et al. Prevention of bloodstream infections by use of daily chlorhexidine baths for patients at a long-term acute care hospital. Infect Control Hosp Epidemiol. 2009;30(11):1031-1035. 11. Popovich K, Hota B, Hayes R, et al. Effectiveness of routine patient cleansing with chlorhexidine gluconate for infection prevention in the medical intensive care unit. Infect Control Hosp Epidemiol. 2009;30(10):959-963. 12. Clark AP, John LD. socomial infections and bath water: any cause for concern? Clin Nurse Spec. 2006;20:119-123. 13. Sievert D, Armola R, Halm MA. Chlorhexidine gluconate bathing: does it decrease hospital-acquired infections? Am J Crit Care. 2011;20:166-170. To purchase electronic or print reprints, contact The InnoVision Group, 101 Columbia, Aliso Viejo, CA 92656. Phone, (800) 899-1712 or (949) 362-2050 (ext 532); fax, (949) 362-2049; e-mail, reprints@aacn.org. 342 AJCC AMERICAN JOURNAL OF CRITICAL CARE, September 2012, Volume 21,. 5 www.ajcconline.org