Evaluation of donor arm disinfection techniques

In situ and in vitro evaluation of two antiseptics for blood bank based on chlorhexidine gluconate/isopropyl alcohol and povidone-iodine

BACKGROUND

Poor disinfection is the main cause of blood contamination, so its elimination is key to limiting the entry of bacteria into the collection system. With the advancement of antiseptic technology, antiseptics with sterile, disposable applicators are now available.

AIM

To evaluate in situ two antiseptics (with and without applicators) for blood banks and to demonstrate in vitro antiseptic activity on bacterial biofilms of importance in transfusion medicine.

METHODS

Antiseptic A (2% sterile solution of chlorhexidine gluconate/70% isopropyl alcohol provided with applicator) and bulk antiseptic B (10% povidone-iodine) were evaluated. The deferred blood donor arms were subjected to disinfection with antiseptics A and B and the contralateral arms were cultured to determine the baseline bacterial load (control). Antiseptic activity was assessed by ANOVA and logaritmic reduction values (LRV) and percentage reduction values (PRV) were calculated. Finally, the in vitro activity of antiseptic A was analyzed by confocal laser scanning microscopy (CLSM) on biofilm models.

RESULTS

Prior to disinfection tests, commensal and clinically important bacteria were identified; antiseptic A showed post-disinfection bacterial growth rates of zero compared to controls (p < 0.0001). The frequency of bacterial growth with antiseptic B was 74%. A significant difference was identified between both antiseptics, where antiseptic A showed higher activity (p < 0.5468). LRV and PRV were 0.6-2.5/100% and 0.3-1.7/66.7-99.7% for antiseptics A and B, respectively. Through CLSM, disinfectant A (without applicator) showed lower in vitro antiseptic activity on the tested biofilms at the exposure times recommended by the manufacturer.

CONCLUSIONS

Sterile solution of chlorhexidine gluconate/isopropyl alcohol with applicator showed advantages disinfection in deferred blood donors over povidone-iodine.

Presence of Gram-negative bacteria and Staphylococcus aureus on the skin of blood donors in the Democratic Republic of the Congo

BACKGROUND

Skin bacteria may contaminate blood products but few data are available on sub-Saharan Africa (sSA). We assessed the presence of Gram-negative bacteria and Staphylococcus aureus on blood donor skin and evaluated skin antisepsis in the Democratic Republic of the Congo (DRC).

STUDY DESIGN AND METHODS

Among blood donors at the National Blood Transfusion Center (NBTC) and at a rural hospital, the antecubital fossa skin of the non-disinfected arm (not used for blood collection) was swabbed (25cm² surface) and cultured for total and Gram-negative bacterial counts. Bacteria were identified with MALDI-TOF and tested for antibiotic susceptibility by disk diffusion. For evaluation of the NBTC antisepsis procedure (i.e., ethanol 70%), the culture results of the disinfected arm (used for blood collection) were compared with those of the non-disinfected arm.

RESULTS

Median total bacterial counts on 161 studied non-disinfected arms were 1065 Colony-Forming Units (CFU) per 25 cm² , with 43.8% (70/160) of blood donors growing Gram-negative bacteria and 3.8% (6/159) Staphylococcus aureus (2/6 methicillin-resistant). Non-fermentative Gram-negative rods predominated (74/93 isolates, majority Pseudomonas spp., Acinetobacter spp.). Enterobacterales comprised 19/93 isolates (mostly Pantoea spp. and Enterobacter spp.), 5/19 were multidrug-resistant. In only two cases (1.9%, 2/108) the NBTC antisepsis procedure met the acceptance criterion of ≤2 CFU/25 cm² .

CONCLUSION

Skin bacterial counts and species among blood donors in DRC were similar to previously studied Caucasian populations, including cold-tolerating species and bacteria previously described in transfusion reactions. Prevention of contamination (e.g., antisepsis) needs further evaluation and customization to sSA.

How to improve aseptic technique to reduce bloodstream infection during vascular access procedures

Bloodstream infections associated with vascular access procedures pose a serious risk to patients that can be reduced by better standards of aseptic technique. The objectives of this roundtable of experts were to achieve a consensus on how to improve skin antisepsis in hospital, improve training, competency, compliance and consistency in skin antisepsis, review the role of devices in improving skin antisepsis, identify methods to improve skin antisepsis integrated with the Aseptic Non Touch Technique (ANTT®) approach, and identify challenges to the implementation of the panel's recommendations. Recommendations include using MHRA-licensed 2% chlorhexidine gluconate in 70% isopropyl alcohol solution with bidirectional strokes for up to 30 seconds, then leaving the skin to air dry for 30 seconds; using the ANTT Clinical Practice Framework and terminology as the standard for skin antisepsis training and practice; standardised ANTT and skin antisepsis education with 3-yearly competency assessments for all UK health professionals; and more research to address the evidence gap on transmission of infection after skin antisepsis.

Peri-Operative Method of Applying Chlorhexidine and Iodine as Skin Preparation Solutions: Does It Matter? A Literature Review

Background: Surgical site infection (SSI) is an adverse event that can lead to increased pain, increased cost, risk of death, and decreased patient satisfaction. Studies have investigated the best solutions to prevent SSI. Chlorhexidine has been suggested as the most efficacious antiseptic. However, scant data exist on application of antiseptic solutions and effectiveness of concentric versus back-and-forth strokes. Because a specific method may result in better outcomes, we aimed to review the literature to compare these two techniques. Methods: PubMed-indexed articles were reviewed using specific keywords, including "back-and-forth," "concentric circle," "chlorhexidine," "iodine," "surgical site infection," "antiseptic," and "skin preparation." Because data showing the correlation between SSI and application method of skin preparation solutions were scant, studies that described skin preparation method but analyzed other types of infection, bacteremia, or colonization were also included in this review. Results: No consensus was found regarding the application method. Two articles showed the superiority of chlorhexidine applied using the back-and-forth technique, whereas one demonstrated the superiority of iodine applied in concentric circles. Conclusions: The method of applying antiseptic solution may be just as important as the choice of solution. More studies are needed to assess method of antiseptic application.

Best practice skin antisepsis for insertion of peripheral catheters

This article discusses the importance of effective skin antisepsis prior to the insertion of peripheral intravenous catheters (PIVCs) and how best clinical practice is promoted by application of an appropriate method of skin disinfection integrated effectively with a proprietary aseptic non touch technique, or other standard aseptic technique. Historically under-reported, incidence of infection and risk to patients from PIVCs is now increasingly being recognised, with new research and evidence raising concern and helping to drive new clinical guidance and improvement. The risks posed by PIVCs are particularly significant given increasing PIVC dwell times, due to cannula removal now being determined by new guidance for clinical indication, rather than predefined time frames. Clinical 'best practice' is considered in context of the evidence base, importantly including availability and access to appropriate skin antisepsis products. In the UK, and other countries, ChloraPrep is the only skin antisepsis applicator licensed as a drug to disinfect skin and help prevent infections before invasive medical procedures, such as injections, blood sampling, insertion of PIVCs and minor or major surgery.

Chlorhexidine alcohol versus povidone-iodine: The comparative study of skin disinfectants at the blood transfusion centers of Iran

OBJECTIVES

The skin disinfection in the blood donor's arm is a key step to minimize the risk of microbial contamination at blood donation sessions. Current study aimed to compare the efficacy of 2% chlorhexidine gluconate in 70% isopropyl alcohol (CHG/IPA) with povidone-Iodine (PI) at blood transfusion centers (BTCs) of Iran.

MATERIAL AND METHODS

Blood donors were selected to evaluate three commercial CHG/IPA disinfectants (N=300), prior the application at BTCs, and to compare the rate of positive skin cultures between CHG/IPA and PI in 31 BTCs (N=8578). The rate of positivity for PI over a 5-year period was also investigated. After application of a two-step disinfection procedure, the biochemical characteristics were checked in accordance with the conventional bacteriological methods. The Z-test analysis was used to compare the deviation between the positive microbial culture ratios.

RESULT

No donors had a positive culture after disinfection during the evaluation study. There was no difference in the rate of positivity between PI and CHG/IPA after disinfection (P>0.05). The rate of positivity for PI from 2012 to 2017 showed a decreasing trend. The rate of positivity was significantly higher in winter rather than summer (P<0.05).

CONCLUSION

The disinfection efficacy of CHG/IPA was equivalent to that of PI. The 5-year monitoring of PI at BTCs showed that the improvement in the rate of positive skin cultures possibly due to effectiveness of correcting actions.

Evaluation of the Role of Novel Aprotic Dimethyl Sulfoxide in Cutaneous Antisepsis Protocols Prior to Blood Donor Phlebotomy with Isopropyl Alcohol, Povidone Iodine or Chlorhexidine

The study was planned to measure the reduction of the load of bacterial flora on the blood donor's arm quantitatively using a three step protocol of donor arm cleansing incorporating either 70% isopropyl alcohol (IPA) or 5% w/v povidone iodine (PVI, 0.5% w/v available iodine) or 4% chlorhexidine gluconate (CHG) with or without the addition of 5% dimethyl sufloxide (DMSO). Single blind randomized study after obtaining ethical clearance, using the Miles and Misra technique for quantification and matrix assisted laser desorption ionization-mass spectrometry for identification of colony morphotypes on blood donor's skin. The mean pre-cleansing colony forming units (CFUs) was 89,318 and mean post-cleansing CFUs was 132, with a mean reduction of 99.85% with a mean log reduction of 3.24 (95% CI 2.01-4.47) at a P value of <0.0001. The post-cleansing CFUs was reduced to zero in all 34 samples in the protocol using CHG with DMSO, in 23 of 31 samples in the protocol using PVI with DMSO and 19 of 29 samples in the protocol using IPA with DMSO. The difference in means of the reduction of CFUs in protocols using CHG with DMSO compared with protocols using PVI or IPA with DMSO and PVI or IPA without DMSO was statistically significant with P value of 0.006, 0.0009, 0.015 and 0.05 respectively. The enhanced cutaneous antisepsis effect of CHG when complimented with DMSO in presence of IPA using the three step protocol of donor arm cleansing could stimulate more research and utilization of this as an additional safety towards the prevention of the problem of bacterial contamination of blood and blood components.

Fixation of the short-term central venous catheter. A comparison of two techniques

Purpose:

To compare the fixation of the central venous catheter (CVC) using two suture techniques.

Methods:

A clinical, analytical, interventional, longitudinal, prospective, controlled, single-blind and randomized study in adult, intensive care unit (ICU) patients. After admission and indication of CVC use, the patients were allocated to the Wing group (n = 35, catheter fixation with clamping wings and retainers) or Shoelace group (n = 35, catheter fixation using shoelace cross-tied sutures around the device). Displacement, kinking, fixation failure, hyperemia at the insertion site, purulent secretion, loss of the device, psychomotor agitation, mental confusion, and bacterial growth at the insertion site were evaluated.

Results:

Compared with the Wing group, the Shoelace group had a lower occurrence of catheter displacement (n=0 versus n =4; p = 0.04), kinking (n=0 versus n=8; p=0.001), and fixation failure (n=2 versus n=8; p=0.018). No significant difference was found in bacterial growth (n=20 versus n=14; p=0.267) between groups.

Conclusion:

The Shoelace fixation technique presented fewer adverse events than the Wing fixation technique.

Skin preparation with alcohol versus alcohol followed by any antiseptic for preventing bacteraemia or contamination of blood for transfusion

BACKGROUND

Blood for transfusion may become contaminated at any point between collection and transfusion and may result in bacteraemia (the presence of bacteria in the blood), severe illness or even death for the blood recipient. Donor arm skin is one potential source of blood contamination, so it is usual to cleanse the skin with an antiseptic before blood donation. One-step and two-step alcohol based antiseptic regimens are both commonly advocated but there is uncertainty as to which is most effective.

OBJECTIVES

To assess the effects of cleansing the skin of blood donors with alcohol in a one-step compared with alcohol in a two-step procedure to prevent contamination of collected blood or bacteraemia in the recipient.

SEARCH METHODS

In December 2014, for this third update, we searched the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL), The Cochrane Library; Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; and EBSCO CINAHL.

SELECTION CRITERIA

All randomised trials (RCTs) comparing alcohol based donor skin cleansing in a one-step versus a two-step process that includes alcohol and any other antiseptic for pre-venepuncture skin cleansing were considered. Quasi randomised trials were to have been considered in the absence of RCTs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion.

MAIN RESULTS

No studies (RCTs or quasi RCTs) met the inclusion criteria.

AUTHORS' CONCLUSIONS

We did not identify any eligible studies for inclusion in this review. It is therefore unclear whether a two-step, alcohol followed by antiseptic skin cleansing process prior to blood donation confers any reduction in the risk of blood contamination or bacteraemia in blood recipients, or conversely whether a one-step process increases risk above that associated with a two-step process.

The right skin preparation technique: a literature review

Recent debates and guidelines are suggesting back and forth motion to be the optimal preoperative technique for skin preparation. There is a lack of conclusive evidence showing this to be the case, but it may be reasonable to follow this technique, in preference to the widely used concentric circles motion, as the antiseptic agent will reach deeper cell layers of the skin where most of the microbes are found.

Skin preparation with alcohol versus alcohol followed by any antiseptic for preventing bacteraemia or contamination of blood for transfusion

BACKGROUND

Blood for transfusion may become contaminated at any point between collection and transfusion and may result in bacteraemia (the presence of bacteria in the blood), severe illness or even death for the blood recipient. Donor arm skin is one potential source of blood contamination, so it is usual to cleanse the skin with an antiseptic before blood donation. One-step and two-step alcohol based antiseptic regimens are both commonly advocated but there is uncertainty as to which is most effective.

OBJECTIVES

To assess the effects of cleansing the skin of blood donors with alcohol in a one-step compared with alcohol in a two-step procedure to prevent contamination of collected blood or bacteraemia in the recipient.

SEARCH METHODS

For this second update we searched the Cochrane Wounds Group Specialised Register (searched 20 November 2012); The Cochrane Central Register of Controlled Trials (CENTRAL) The Cochrane Library 2012, Issue 11; Ovid MEDLINE (20011 to November Week 2 2012); Ovid MEDLINE (In-Process & Other Non-Indexed Citations November 20, 2012); Ovid EMBASE ( 20011 to 2012 Week 46); and EBSCO CINAHL ( 2008 to 15 November 2012).

SELECTION CRITERIA

All randomised trials (RCTs) comparing alcohol based donor skin cleansing in a one-step versus a two-step process that includes alcohol and any other antiseptic for pre-venepuncture skin cleansing were considered. Quasi randomised trials were to have been considered in the absence of RCTs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion.

MAIN RESULTS

No studies (RCTs or quasi RCTs) met the inclusion criteria.

AUTHORS' CONCLUSIONS

We did not identify any eligible studies for inclusion in this review. It is therefore unclear whether a two-step, alcohol followed by antiseptic skin cleansing process prior to blood donation confers any reduction in the risk of blood contamination or bacteraemia in blood recipients, or conversely whether a one-step process increases risk above that associated with a two-step process.

Impact of donor arm cleaning with different aseptic solutions for prevention of contamination in blood bags

Transfusion associated sepsis cases are encountered occasionally and bacterial transmission remains the major cause. The goal of our study was to compare the efficacy of disinfectants in phlebotomy site preparation. After selection of donor the antecubital fossa area of the arm was disinfected with different types of disinfectants namely sprit (70% isopropyl alcohol), povidone iodine (0.5% w/v available iodine in distilled water), savlon (1.5% v/v chlorhexidine gluconate solution and 3.0% cetrimide solution) and combination of sprit and povidone iodine. Swabs were collected from 20 donors using a sterile forceps, after cleaning with different antiseptic solutions. Swab was streaked on blood agar plate aseptically and the plate was incubated at 37°C for 24 h. Colonies were counted and a single colony was re-cultured by growing on nutrient and Mac-Conkey agar. The biochemical characteristics were determined by performing Gram staining, Motility, Catalase and Oxidase tests. The mean values of colonies were significantly higher with savlon compared to other three solutions. The difference was statistically significant by "t" test (t values 1.7-3.0; P < 0.05). Staphylococcus epidermidis, Staphylococcus sp., Streptococcus sp., Micrococcus sp., Bacillus megaterium and Bacillus cereus were the organisms identified. After completion of bleeding, samples from the bag were aseptically inoculated in aerobic and anaerobic culture bottles to be tested on BacT/Alert system. The bag containing donor's blood did not show any contamination when three cleanings were carried out using sprit, povidone iodine and spirit respectively.

Interventions Implemented to Reduce the Risk of Transmission of Bacteria by Transfusion in the English National Blood Service

SUMMARY: BACKGROUND: Bacterial contamination remains a significant problem in transfusion medicine. A National Health Service Blood and Transplant (NHSBT) study and surveillance data indicated skin commensals derived from the skin of the donor are the major contaminants of blood components. NHSBT therefore explored two interventions: improved donor arm disinfection and diversion. METHODS: IMPROVED DONOR ARM DISINFECTION: Commercial and in-house methods of disinfection were evaluated. Swabs at the venepuncture site were taken before and after disinfection and the reduction in bioburden determined. Diversion: Special collection bags were manufactured to allow the initial volume of blood to flow into a pouch, representing the diversion pouch and then the next flow of blood into another pouch representing the collection bag. Pouches were screened for the presence of bacteria. The reduction in bacterial contamination was then determined. RESULTS: A two-step commercial procedure (Donor Prep Kit; DPK) consisting of 70% isopropyl alcohol followed by tincture of iodine was shown to be a best practice procedure (2-min procedure). A 99.79% reduction was obtained, and this method was 10 times more effective than current practice at that time. The DPK was shown in a field trial to increase donor waiting time. A second study was initiated to find a more rapid procedure. ChloraPrep®, consisting of 2% chlorhexidine gluconate and 70% isopropyl alcohol, was shown to have equivalent disinfection efficiency as the DPK, but only took 1 min to perform. In 2006, ChloraPrep was introduced as the national method of donor arm disinfection. Diversion was shown to give a 47% reduction in contamination and was introduced nationally in 2002. CONCLUSION: Improved donor arm disinfection and diversion are effective, low-cost interventions, but do not eliminate all bacterial transmissions. In 2011, bacterial screening of platelet components was introduced by NHSBT to further increase the safety of the blood supply.

A novel rapid and effective donor arm disinfection method

BACKGROUND

The aim of the study was to derive a donor arm disinfection technique that was rapid, but with a disinfection efficacy equivalent to a previous "best-practice" technique. This method consisted of a two-stage procedure with an initial application of 70% isopropyl alcohol and then 2% tincture of iodine (IATI). The total time for the IATI method was 2 minutes in duration. A rapid technique (1 min in duration) was needed to obviate potential problems due to increased donor waiting time, had the IATI method been implemented at blood donation sessions.

STUDY DESIGN AND METHODS

A direct swabbing and plating technique was used to enumerate bacteria present before and after disinfection. In total, seven methods were evaluated.

RESULTS

The chlorhexidine/alcohol applicator (CAA) disinfection device containing 1.5 mL of 2% chlorhexidine gluconate and 70% isopropyl alcohol (99.91% reduction; confidence limits, 99.55%, 99.98%) was shown to have equivalent disinfection efficacy as the IATI method (99.89% reduction; confidence limits, 99.36%, 99.98%; p = 0.86). Procedural time for the 1.5-mL CAA method was 1 minute thereby avoiding potential problems of increased donor waiting time, inherent in the IATI 2-minute procedure at blood donation sessions.

CONCLUSIONS

The 1.5-mL CAA disinfection method offers blood services a rapid and effective donor arm disinfection procedure. In 2006, the 1.5-mL CAA procedure was implemented throughout the entire English blood service for all donations.

Skin disinfection methods: prospective evaluation and postimplementation results

BACKGROUND

Optimal skin disinfection ensures blood safety. In this study, efficacies of the two-step skin disinfection methods used at Canadian Blood Services (CBS) and two one-step methods produced by different manufacturers were compared.

STUDY DESIGN AND METHODS

In each of the three phases of the study, two methods were compared by disinfection of the antecubital fossae of study subjects. The two-step methods were compared in Phase I: Method A (isopropyl alcohol scrub and iodine tincture ampule) and Method B (isopropyl alcohol and chlorhexidine scrub and isopropyl alcohol and chlorhexidine ampule). In Phases II and III, Method B was compared to two different one-step swab sticks containing isopropyl alcohol and chlorhexidine (Methods C and D). Contact plates were applied on each of the subjects before and after disinfection and incubated at 37 degrees C for 24 hours followed by colony counting.

RESULTS

In 99% of the subjects, colonies per plate were reduced from approximately 60 to less than 10 after disinfection using any method. Method B was superior to Method A (p < 0.05) but was not significantly different from Methods C and D. Method D was implemented for skin disinfection at CBS with no significant effects on blood product contamination. Skin reactions increased from approximately 0.02% to approximately 0.62% after implementation, which were subsequently reduced to approximately 0.04%.

CONCLUSION

In this study, isopropyl alcohol and chlorhexidine disinfectants were more efficacious than isopropyl alcohol and iodine. There was no difference in efficacy between one-step and two-step procedures or between methods of application. A one-step chlorhexidine and isopropyl alcohol kit has been successfully implemented at CBS.

Bacterial contamination of platelets

Bacterial contamination of platelet products, both single donor apheresis platelet units and whole blood-derived platelet pools, continues to occur despite preventive measures. While some advances have been made in decreasing the rate of bacterial contamination of platelet units, particularly through diversion methods and early culture, a great deal remains to be done to eliminate the problem. Diversion methods have decreased contamination rates associated with skin commensal organisms. Culture methods are now widely used and many at-issue detection methods have been developed or are undergoing development. This article reviews the current developments and the challenges that remain to minimize and detect bacterial contamination of platelet products.

Pooled platelet concentrates: an alternative to single donor apheresis platelets?

Three types of platelet concentrates (PC) are compared: PC either processed with the platelet-rich plasma (PRP) or the Buffy coat (BC) method from whole blood units and PC obtained by apheresis. Leuko-reduction (LR) pre-storage is advocated to improve quality of the PC during storage and reduce adverse reactions in recipients. Standardization of methods allow preparation of PC with comparable yields of approximately 400 x 10(9) platelets in pooled non-LR-PRP, approximately 370 x 10(9) in pooled LR-BC-PC and in LR apheresis PC the number of platelets can be targeted on 350 x 10(9) or more with devices of various manufacturers. While viral transmission can be prevented by outstanding laboratory tests, the risk of bacterial contamination should be reduced by improved arm disinfection, deviation of the first 20-30 ml of blood and culture or rapid detection assays of the PC pre-issue. In a large prospective multicenter trial no significant difference was observed between cultures of apheresis PC (n = 15,198): 0.09% confirmed positive units versus 0.06% in pooled BC-PC (n = 37,045), respectively. Though platelet activation as measured by CD62 expression may differ in vitro in PC obtained with various apheresis equipment, and also between PC processed with the two whole blood methods there is scarce literature about the clinical impact of these findings. In conclusion the final products of LR-PC derived from whole blood or obtained by apheresis can be comparable, provided the critical steps of the processing method are identified and covered and the process is in control.

Skin preparation with alcohol versus alcohol followed by any antiseptic for preventing bacteraemia or contamination of blood for transfusion

BACKGROUND

Blood for transfusion may become contaminated at any point between collection and transfusion and may result in bacteraemia (the presence of bacteria in the blood), severe illness or even death for the blood recipient. Donor arm skin is one potential source of blood contamination, so it is usual to cleanse the skin with an antiseptic before blood donation. One-step and two-step alcohol based antiseptic regimens are both commonly advocated but there is uncertainty as to which is most effective.

OBJECTIVES

To assess the effects of cleansing the skin of blood donors with alcohol in a one-step compared with alcohol in a two-step procedure to prevent contamination of collected blood or bacteraemia in the recipient.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (March 10 2009); The Cochrane Central Register of Controlled Trials (CENTRAL) The Cochrane Library 2009, Issue 1; Ovid MEDLINE - (1950 to February Week 4 2009); Ovid EMBASE - (1980 to 2009 Week 9); and EBSCO CINAHL - (1982 to February Week 4 2009). We also searched the reference lists of key papers.

SELECTION CRITERIA

All randomised trials (RCTs) comparing alcohol based donor skin cleansing in a one-step versus a two-step process that includes alcohol and any other antiseptic for pre-venepuncture skin cleansing were considered. Quasi randomised trials were to have been considered in the absence of RCTs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion.

MAIN RESULTS

No studies (RCTs or quasi RCTs) met the inclusion criteria.

AUTHORS' CONCLUSIONS

We did not identify any eligible studies for inclusion in this review. It is therefore unclear whether a two-step, alcohol followed by antiseptic skin cleansing process prior to blood donation confers any reduction in the risk of blood contamination or bacteraemia in blood recipients, or conversely whether a one-step process increases risk above that associated with a two-step process.

Bacterial contamination of platelet concentrates: results of a prospective multicenter study comparing pooled whole blood-derived platelets and apheresis platelets

BACKGROUND

The GERMS Group initiated a prospective multicenter study to assess prevalence and nature of bacterial contamination of pooled buffy-coat platelet concentrates (PPCs) and apheresis platelet concentrates (APCs) by routine screening with a bacterial culture system.

STUDY DESIGN AND METHODS

In nine centers overall, 52,243 platelet (PLT) concentrates (15,198 APCs, 37,045 PPCs) were analyzed by aerobic and anaerobic cultures (BacT/ALERT, bioMérieux).

RESULTS

In 135 PLT concentrates (PCs; 0.26%), bacteria could be identified in the first culture (0.4% for APCs vs. 0.2% for PPCs; p < 0.001). In 37 (0.07%) of these PC units, the same bacteria strain could be identified in a second culture from the sample bag and/or the PC unit. The rate of confirmed-positive units did not differ significantly between APC (0.09%; 1/1169) and PPC units (0.06%; 1/1544). Bacteria from skin flora (Propionibacterium acnes, Staphylococcus epidermidis) were the most prevalent contaminants. Median times to first positive culture from start of incubation were 0.7 and 3.7 days in aerobic and anaerobic cultures for confirmed-positive units. With a "negative-to-date" issue strategy, most PC units (55%) had already been issued by time of the first positive culture.

CONCLUSION

The rate of confirmed bacterial contamination of PC units was low. Nevertheless, clinicians must be aware of this risk. The risk of bacterial contamination does not warrant universal preference of APCs. It must be questioned whether routine bacterial screening by a culture method can sufficiently prevent contaminated products from being transfused due to the delay until a positive signal in the culture system and due to false-negative results.

Platelet Transfusion Therapy

This article provides guidelines for the appropriate use of platelet transfusions to reduce unnecessary transfusions, thereby avoiding transfusion-related risks to the patients and the costs of platelet therapy. Platelet products available for transfusion are whole blood derived platelet concentrates and apheresis platelets. Leukoreduced platelets can be used to reduce platelet alloimmunization, cytomegalovirus transmission, and febrile transfusion reactions, while gamma irradiation prevents transfusion-associated graftversus-host disease. Other topics discussed are the expected response to transfused platelets and reasons for poor responses related to alloimmunization, underlying disease state, clinical conditions, and drugs. Appropriate transfusion guidelines based on pretransfusion platelet count, platelet dose, and whether the transfusion is prophylactic or therapeutic are outlined. Identification, prevention, and management of adverse consequences of platelet transfusions and platelet refractoriness are discussed.

From the donor's arm to blood product: a study on bacterial contamination of apheresis platelet concentrates

BACKGROUND

Transfusion-associated bacterial infections are a quite frequent collateral effect of administration of platelet concentrates (PC). We carried out a microbiological surveillance of bacterial contamination of apheresis platelet concentrates by studying microbial flora on donors' arms before and after skin disinfection, through blood cultures with the diversion volume and with the PC.

MATERIALS AND METHODS

Platelet aphereses were carried out using two Haemonetics MCS+ instruments. Cutaneous swabs were examined by the direct plate technique and blood cultures were performed using Bact/ALERT aerobic bottles. In the 5 years from January 2001 to December 2005 we tested 481 PC.

RESULTS

Cutaneous swabs showed significant bacterial growth in 89% of cases before skin disinfection and in 44% after. None of the blood cultures performed on diversion blood was positive, one (0.2%) PC was positive on the fifth day after collection and the presence of a Staphylococcus epidermidis strain was demonstrated.

CONCLUSIONS

Our results suggest that the skin disinfection protocol adopted in our structure is not fully satisfactory. The cultures performed on the PC showed a low prevalence of contamination, and the only positive sample was contaminated by a common skin contaminant (S. epidermidis). The culture became positive on the fifth day after collection, but on the second day the PC had been transfused to a patient, without any adverse reaction. In our experience a culture method using Bact/ALERT aerobic bottles was not able to prevent transfusion of the only contaminated PC identified in this study.

Bacterial screening of apheresis platelets and the residual risk of septic transfusion reactions: the American Red Cross experience (2004-2006)

BACKGROUND

The American Red Cross initiated systemwide bacterial testing of all apheresis platelet (PLT) collections in March 2004, yet continues to receive reports of septic reactions after transfusion of screened components.

STUDY DESIGN AND METHODS

The rates of confirmed bacterial contamination of apheresis PLT collections detected by prospective quality control (QC) testing, and by surveillance of reported septic reactions to screened-negative apheresis PLTs, were analyzed according to the technology utilized for collection.

RESULTS

Between March 1, 2004, and May 31, 2006, bacterial culture testing was performed on 1,004,206 donations; of these, 186 (1:5,399) had confirmed-positive culture results. Transfusion of all but 1 of the associated 293 components was prevented. A significantly higher rate of confirmed-positive bacterial cultures was seen with products collected utilizing two-arm collection procedures compared to one-arm procedures (22.7 vs. 11.9 per 10(5) donations; odds ratio [OR], 1.9; 95% confidence interval [CI], 1.4-2.7). During this period, 20 septic transfusion reactions were reported, including 3 fatalities (1:498,711 fatalities per distributed component), which implicated screened-negative apheresis PLT products. The frequency of septic reactions was 4.7-fold higher for collections utilizing two-arm procedures (1:41,173; 95% CI, 1:25,000-1:66,667) compared to collections from one-arm procedures (1:193,305; 95% CI, 1:52,632-1:500,000; OR, 4.7; 95% CI, 1.2-18.4); most septic reactions (16 of 20) were due to Staphylococcus spp. and occurred on Day 5 (13 of 20) after collection.

CONCLUSION

PLT contamination with bacteria that evade detection by QC culture remains a significant residual transfusion risk, in particular for older PLTs and skin-commensal bacteria in components collected by two-arm apheresis procedures during the study period.

Transfusion-transmitted infections

Although the risk of transfusion-transmitted infections today is lower than ever, the supply of safe blood products remains subject to contamination with known and yet to be identified human pathogens. Only continuous improvement and implementation of donor selection, sensitive screening tests and effective inactivation procedures can ensure the elimination, or at least reduction, of the risk of acquiring transfusion transmitted infections. In addition, ongoing education and up-to-date information regarding infectious agents that are potentially transmitted via blood components is necessary to promote the reporting of adverse events, an important component of transfusion transmitted disease surveillance. Thus, the collaboration of all parties involved in transfusion medicine, including national haemovigilance systems, is crucial for protecting a secure blood product supply from known and emerging blood-borne pathogens.

Canadian experience with detection of bacterial contamination in apheresis platelets

BACKGROUND

In Canada, both blood suppliers, Héma-Québec (HQ) and Canadian Blood Services (CBS), implemented bacterial testing in apheresis platelets (PLTs) with an automated microbial detection system (BacT/ALERT, bioMérieux).

STUDY DESIGN AND METHODS

Validation of the BacT/ALERT Classic and 3D systems involved apheresis PLT spiking with different bacteria at concentrations of 10 and 10(2) colony-forming units per mL. As of February 2006, more than 95 percent of apheresis PLTs were screened for bacterial contamination at HQ and CBS. Between 3.5 and 10 mL of PLTs is inoculated into BacT/ALERT aerobic culture bottles followed by incubation for a maximum of 7 days.

RESULTS

During the validation studies, all bacteria were detected at all concentrations and volumes tested. Upon implementation of bacterial screening, the percentage of initial positive samples at CBS and HQ was 0.09 and 0.07 percent, respectively. The rate of indeterminate cultures was significantly higher at CBS than at HQ, whereas the rates for true-positive, false-positive, and false-negative results did not differ significantly. Six confirmed-positive cultures, including three coagulase-negative staphylococci and three Enterobacteriaceae species, were detected and PLT units contaminated with these bacteria were not transfused. The rate of true-positive cultures was significantly lower than that reported by other blood operators. Unfortunately, failed detection of two contaminated units resulted in septic transfusion reactions.

CONCLUSION

Bacterial screening of apheresis PLTs in Canada was successfully implemented, and transfusion of contaminated units was prevented. Rapid bacterial detection systems that could be used before transfusion, however, may further reduce the risk of transfusion reactions.

[New container of sample: role in the reduction of bacterial contamination of standard platelet units]

BACKGROUND

Bacterial contamination of unstable blood products constitutes today the most frequent infectious risk transmitted by blood transfusion. Platelet concentrates are often incrimineted. As responsible germs are in general of cutaneous origin, a sample procedure with diversion of the first 20 ml during blood donation is studied. The aim of this study is to evaluate the results of this technique on bacterial contamination rate of standard platelet units prepared at the regional blood transfusion center in Casablanca.

STUDY DESIGN AND METHODS

A comparative study of two types of sample pockets is made: 500 Standard Platelet concentrates (CPS) are prepared after collection using standard triple bags (Baxter) (group 1) and 560 pockets of CPS were prepared after collection using triple bags with Sample Diversion Pouch sampling system for elimination of the first 20 ml of donation (Macopharma and Terumo) (group 2). The skin was disinfected in two times with alcohol 70%. The bacteriological study was made in the two groups at the third day of conservation.

RESULTS

Six CPS of group 1 were contaminated, of which five were staphylococci coagulase negative and one bacillus sp. Six CPS of group 2 were contaminated, of which five were staphylococci coagulase negative and one staphylococcus aureus. The bacteria isolated were those of cutaneous flora at 100%. Diversion of first 20 ml of blood donation results in a 16.6% reduction in bacterial contamination of CPS (P>0.05).

CONCLUSION

The non-significant reduction in the prevalence of the bacterial infection of CP formulates the problem of the indication of the sampling devices with derivation of first 20 ml during blood collection.

Bacterial risk reduction by improved donor arm disinfection, diversion and bacterial screening

The Interventions of improved donor arm disinfection, diversion and bacterial screening have been implemented by blood services and shown to have substantial benefit. The major source of bacterial contamination is donor arm derived. Blood services are now introducing best practice donor arm disinfection techniques. Diversion has been shown to substantially reduce bacterial contamination in the order of 40-88%. Diversion, together with improved donor arm disinfection, has shown to improve the percentage of reduction in contamination from 47% to 77%. Residual contamination levels after the Introduction of diversion and improved donor arm disinfection may be in the order of 30-40%. Numerous countries have now implemented screen testing programmes for platelet concentrates, which are the major source of bacterial transfusion transmission. Pathogen reduction systems have been developed and are under development. At present, concerns remain with these systems regarding cost, process control, ability to inactivate high titres of viruses, killing of bacterial spores, product damage, genotoxicity and mutagenicity. The interventions of diversion, improved donor arm disinfection and bacterial screen testing are currently available, As such they can be implemented now to increase blood safety with no associated patient risk.

Effects of skin disinfection method, deviation bag, and bacterial screening on clinical safety of platelet transfusions in the Netherlands

BACKGROUND

Bacterial contamination of blood products is a great hazard for development of fatal transfusion reactions. Bacterial screening of platelet concentrates (PC) by aerobic and anaerobic culturing (BacT/ALERT, bioMérieux) was introduced in the Netherlands in October 2001.

STUDY DESIGN AND METHODS

In November 2002, a nationwide, uniform skin cleansing method was introduced with a double-swab disinfection with 70 percent isopropyl alcohol. One location routinely used an integrated diversion bag to collect the first 20 to 30 mL.

RESULTS

Over the calendar years 2002 and 2003, in total 113,093 PCs derived from pooled buffy coats were screened. After introduction of the new disinfection method, 0.85 percent were initially positive. This was a small reduction compared to the previous disinfection methods under which 0.95 percent were initially positive. The location with use of the diversion bag showed a significantly lower frequency of bacterial contamination, with 0.50 percent before and 0.37 percent after introduction of 70 percent isopropyl alcohol. In addition 8000 apheresis PCs were also screened, showing 24 initially positive samples (0.30%).

CONCLUSION

The use of the diversion bag and, to a lesser extent, the use of double swabs with 70 percent isopropyl alcohol, led to a reduction of contamination. As expected, predominant contamination with resident skin bacteria was reduced. The combination of diversion bag and new disinfection led to a frequency of initial positive results for pooled five-donor PCs, which is similar to that of single-donor apheresis PCs. Furthermore, the bacterial detection system and associated product recall procedures have been shown to be effective in preventing transfusion of contaminated PCs and/or related red cells, especially for rapidly growing bacteria.

Optimized Scansystemtm platelet kit for bacterial detection with enhanced sensitivity: detection within 24 h after spiking

BACKGROUND AND OBJECTIVES

The prevention and detection of bacterial contamination of platelet concentrates remains a major challenge for transfusion medicine. To be suitable for blood-transfusion services, the contamination detection method must be highly sensitive, easy to perform and preferably of low cost. In this spiking study, we evaluated the new optimized Scansystem Platelet Kit detection method for use on apheresis platelets.

STUDY DESIGN AND METHODS

Apheresis platelet concentrates (APCs) were individually spiked with 10 colony-forming units (CFU)/ml of one of 10 different strains of bacteria. The spiked APCs were analysed at specific time-points during incubation by using the optimized Scansystem Platelet Kit. Bacterial enumeration was performed by plating onto blood agar.

RESULTS

All the bacterial strains tested were detected by using the optimized Scansystem Platelet Kit when sampled 24 h after spiking. Compared to the Scansystem standard kit, sensitivity was increased to < 50 CFU/ml. The identity of the spiked bacteria was confirmed by Gram staining and DNA fingerprinting.

CONCLUSION

The optimized Scansystem Platelet Kit was able to reliably detect, within 70 min, 10 transfusion-relevant bacterial species in APCs when a sample volume was taken 24 h after spiking. This is the first study carried out by using the optimized Scansystem bacterial detection that was found to have an enhanced sensitivity compared to the standard kit.

Pall eBDS: an enhanced bacterial detection system for screening platelet concentrates

Bacterial contamination of blood components remains a significant problem in transfusion medicine. The Pall enhanced bacterial detection system (Pall eBDS) detects the presence of bacteria in leucodepleted platelet concentrates by measuring the reduction of oxygen in the sample, due to aerobic bacterial growth. Pooled platelet concentrates were spiked at 10 cfu mL(-1) with 10 organisms (one species per bag). Pall eBDS pouches were inoculated with the spiked platelet concentrates. After 24 and 30 h of incubation, the oxygen level was measured. A further set of pouches were taken from the inoculated platelet concentrates at 24 h. Incubation and reading intervals were as for the initial set of pouches. A sensitivity study was also performed comparing the Pall eBDS with the BacT/ALERT system. Spiking at 10 cfu mL(-1) and immediately sampling into Pall eBDS pouches resulted in 97.6 and 100% detection after an incubation period of 24 and 30 h, respectively. After 24 h of incubation of the spiked platelet concentrates and then sampling into Pall eBDS pouches, 99.1% detection was obtained after incubation for both 24 and 30 h. The sensitivity of the Pall eBDS and BacT/ALERT is similar and in the order of 1 cfu mL(-1). Implementation of either BacT/ALERT or Pall eBDS for routine screening of platelet concentrates has the potential to further increase the safety of the blood supply.

Bacterial contamination of blood components

Blood for transfusion is a potential source of infection by a variety of known and unknown transmissible agents. Over the last 20 years, astounding reductions in the risk of viral infection via allogeneic blood have been achieved. As a result of this success, bacterial contamination of blood products has emerged as the greatest residual source of transfusion-transmitted disease. This paper summarizes the current status of detection, prevention, and elimination of bacteria in blood products for transfusion.