Juan M. Muñoz

Chlorhexidine is a better antiseptic than povidone iodine and sodium hypochlorite because of its substantive effect

BACKGROUND The present study compared both the antiseptic efficacy of sodium hypochlorite against that of chlorhexidine gluconate in isopropyl alcohol and the substantive effect of chlorhexidine, povidone iodine, and sodium hypochlorite. METHODS This was a 2-step study that included volunteers. In step 1, 4 skin areas were tested for bacteria in colony-forming units (CFU): 2 were controls to determine baseline bacteria or the effect of scrubbing, and 2 were treated with 10% hypochlorite or 2% chlorhexidine in isopropyl alcohol. Every subject was tested 4 times. The second step tested the substantive effect of 10% povidone-iodine and the aforementioned antiseptics. RESULTS For the first step, 30 volunteers were studied, resulting in 120 determinations for each control and antiseptic. No differences between chlorhexidine gluconate (median 115 CFU/cm(2)) and sodium hypochlorite (median 115 CFU/cm(2)) were found. Both antiseptics were significantly different from rubbing control (317 CFU/cm(2)) and basal control (606 CFU/cm(2)). Only chlorhexidine showed a substantive effect. CONCLUSION We consider that chlorhexidine gluconate in isopropyl alcohol, sodium hypochlorite, and povidone-iodine is equally effective for procedures that do not require a long action. However, chlorhexidine is desirable for procedures such as catheter insertion, skin preparation for surgery, or handwashing prior to surgery.

Contamination of intravenous fluids: A continuing cause of hospital bacteremia

BACKGROUND Nosocomial bacteremia caused by the contamination of intravenous (IV) infusates is considered rare. Unfortunately, this problem has been underestimated because its identification requires culturing infusates, a procedure not performed routinely. METHODS This study was conducted in a referral hospital where IV infusates are admixed in nursing areas. The aim was to determine the prevalence of infusate contamination in adult patients with gram-negative rod (GNR) bacteremia. Over a period of 32 months, a specimen of infusate was drawn for culture from each patient recruited after the laboratory reported a GNR in the blood. RESULTS A total of 384 infusates were cultured from 384 patients who had been diagnosed with GNR bacteremia. Seven infusates grew a GNR in culture, for a contamination rate of 2% (7/384; 95% confidence interval [CI] = 1% to 3%). In all cases, the infectious organism was the same as the organism isolated from the blood. Infusate contamination was responsible for 7% (7/108; 95% CI = 2% to 11%) of all primary bloodstream infections and 11% (7/62; 95% CI = 2% to 22%) of all primary bloodstream infections not associated with central venous catheter infection. CONCLUSIONS For patients in hospitals where IV drugs are admixed in nursing units, we recommend instituting infusate culture as routine practice following the diagnosis of a GNR in the blood.

Nosocomial bacteremia in neonates related to poor standards of care.

Background: In developing countries, intravenous liquids are mixed and administered by nurses, sometimes under suboptimal infection control conditions. We hypothesized that outbreaks of infusate-associated neonatal bacteremias are common, and we evaluated whether they can be detected by vigilant microbiologic surveillance of infusates. Methods: We studied intravenous infusates administered to neonates in a Mexican hospital where mixtures of infusates were prepared in hospital wards. The study was performed in 3 stages: stage 1, initial culturing of in-use infusates under basal conditions; stage 2, prospective culturing during a cluster of clinical sepsis; and stage 3, final culturing once the outbreak was controlled. Results: In stage 1, 68 infusates were sterile, and 1 was contaminated with Staphylococcus aureus (1.45%), from 23 patients. In stage 2, of 182 infusates from 39 patients, 51 infusates (28%) were contaminated with Gram-negative rods. On the first day of stage 2, 11 of 15 infusates were contaminated with the same strain of Klebsiella pneumoniae, which continued to appear for 26 days. Another 4 strains of Gram-negative rods were also isolated during stage 2. The association between contaminated infusate and death was significant (odds ratio, 9.4; 95% confidence interval, 2–44.3; P < 0.001). Mixtures made by nurses were more likely contaminated than commercial preparations (odds ratio, 3.1; 95% confidence interval, 1.1–8.5; P = 0.037). In stage 3, there were 42 sterile infusates from 22 patients. Conclusions: Our study suggests that poor standards of care common in hospitals from developing countries sometimes result in outbreaks of sepsis and death for newborn patients.

Endemic infusate contamination and related bacteremia.

BACKGROUND Recent reports suggest that in-use contamination of intravenous infusates is uncommon in hospitals with good standards of care. METHODS We conducted a survey in a referral hospital in Mexico with good standards of care but no pharmacists to prepare intravenous infusates; we tested the a priori hypothesis that the contamination rate is zero. Using a sterile syringe, we took an initial infusate specimen at the time of recruitment, specimen 1, for culture. We took a second specimen, specimen 2, from administration sets that were maintained for 72 hours. Blood cultures were obtained at the discretion of the physicians caring for the patients. RESULTS We cultured 1093 infusate specimens from 621 administration sets comprising 421 patients. We obtained a specimen 1 from each of the enrolled sets and a specimen 2 from 472 sets (76%). We analyzed 10 significant cultures and obtained a global infusate contamination rate of 0.9% (10/1093; 95% CI: 0.5%-1.7%). Two cases of infusate-related bacteremia occurred, establishing a global rate of 0.003/72 infusion hours. CONCLUSIONS Even in institutions with good nursing standards, endemic in-use infusate contamination may be a present danger. We must avoid the use of intravenous therapy whenever possible.

Stethoscopes as potential intrahospital carriers of pathogenic microorganisms

Stethoscopes can take part in the transmission of health care-associated infections. We cultured 112 stethoscopes by direct imprint on blood agar to estimate the prevalence of potentially pathogenic microorganisms. Forty-eight (47%) produced 50 potentially pathogenic microorganisms; from these, 43 (86%) were Staphylococcus aureus, of which 18 (42%) were methicillin-resistant S. aureus. We concluded that stethoscopes should be considered as potential fomites and must be disinfected routinely before and after each patient contact.

Nosocomial pediatric bacteremia: the role of intravenous set contamination in developing countries.

OBJECTIVE To assess the rate of bacterial contamination of intravenous administration sets at their rubber injection ports and matching infusates. DESIGN Cultures of injection ports and infusate during 26 visits to 4 hospitals. SETTING Four public general pediatric hospitals in Mexico City with substandard care practices. PATIENTS Hospitalized pediatric patients receiving intravenous solutions. RESULTS Overall, 176 of 251 injection ports were contaminated (70.1%; 95% confidence interval [CI95], 64.5% to 75.8%), 35 (13.9%; CI95, 9.7% to 18.2%) with gram-negative rods, primarily of the tribe Klebsielleae. Cultures of infusates were positive in 17 cases (6.8%, CI95, 3.7% to 9.9%), 5 of which grew gram-negative rods (2%; CI95, 0.6% to 4.6%). In 3 cases (1.2%), the same species with gram-negative rods was found in the infusates and on the injection ports. During one visit, 8 clustered cases of injection port contamination with a clonal Enterobacter cloacae were found; this agent was also found in the blood culture, intravenous fluid, and parenteral nutrition of one patient. Inadequate chlorination of tap water, a potential risk factor, was recorded during 22 visits (84.6%). CONCLUSION These data suggest that external contamination of the intravenous administration set could play a role in infusate contamination.

Antimicrobial activity of copper against organisms in aqueous solution: a case for copper-based water pipelines in hospitals?

BACKGROUND An association exists between water of poor quality and health care-associated infections. Copper shows microbiocidal action on dry surfaces; it is necessary to evaluate its antimicrobial effect against organisms in aqueous solution. OBJECTIVE The objective was to determine the in vitro antimicrobial activity of copper against common nosocomial pathogens in aqueous solution. METHODS Copper and polyvinyl chloride containers were used. Glass was used as control material. Fourteen organisms isolated from hospital-acquired infections, and 3 control strains were tested. Inocula were prepared by direct suspension of colonies in saline solution and water in each container tested. Bacterial counts in colony-forming units (CFU)/mL were determined at the beginning of the experiment; at 30 minutes; and at 1, 2, 24, and 48 hours. RESULTS Organisms in glass and polyvinyl chloride remained viable until the end of the experiment. Organisms in copper showed a reduction from more than 100,000 CFU/mL to 0 CFU/mL within the first 2 hours of contact (F > 4.29, P < .001). CONCLUSION Copper containers show microbiocidal action on organisms in aqueous solution. Copper may contribute to the quality of water for human use, particularly in hospitals.

Chlorhexidine avoids skin bacteria recolonization more than triclosan

BACKGROUND We do not know whether differences exist between the residual effect of 2% chlorhexidine in 70% isopropyl alcohol when compared with 1% triclosan in 70% isopropyl alcohol. METHODS Using an analytic, longitudinal, controlled, and comparative experimental trial, with blinded measurements, we recruited healthy, adult volunteers from the University of Guanajuato who completed a stabilization phase of skin microbiota and had no history of skin allergies. Four 25-cm2 areas of the inner surface of the forearms were designated for study: unscrubbed control for establishing baseline bacterial counts, scrubbed control with tridistilled water, scrubbed with chlorhexidine, and scrubbed with triclosan. Quantitative cultures were taken of all the areas at 0, 3, and 24 hours, using agar plates with neutralizing agents. RESULTS A total of 135 healthy volunteers were tested. At 24 hours, the unscrubbed control counts were 288 CFU/cm2, whereas the scrubbed control counts were 96 CFU/cm2; 24 CFU/cm2 for chlorhexidine and 96 CFU/cm2 for triclosan (Kruskal-Wallis χ2H = 64.27; P <.001). CONCLUSIONS Chlorhexidine is the best antiseptic option when a prolonged antiseptic effect is needed; for instance, when implanting medical devices or performing surgical procedures.

Salvaging diabetic foot through debridement, pressure alleviation, metabolic control, and antibiotics

There is a fatalist perception of diabetic foot because the argument of “small‐vessel disease” prevails. This is the report of a cohort study of patients facing a formal recommendation for major foot amputation to assess how many can be saved with a conventional treatment, defined as debridement, pressure alleviation, metabolic control, and antibiotics. The primary efficacy measurement was the salvage of the limb at the follow‐up visit between 25 and 35 days after the first consultation. The secondary efficacy measurement was the subsequent epithelization of the ulcerative lesions, following patients for up to 270 days. The cohort consisted of 105 type 2 diabetic patients; 87 (83%) had severe lesions. A total of 71 patients (68%) required hospitalization. By the intention‐to‐treat analysis, 89 patients (85%) avoided major amputation. A total of 88 patients were evaluated for complete epithelization, reaching median success by day 120. Overall, 51 patients (49%) underwent minor amputations. It was concluded that there is a high rate of unnecessary major foot amputations, because a diabetic foot can be salvaged across the continuum of severity when patients receive care in a multidisciplinary wound clinic.

Control de bacteriemia nosocomial pediátrica mediante un programa de cultivo de soluciones parenterales en uso

OBJETIVO. Dado que Klebsiella, Enterobacter y Serratia se multiplican en soluciones parenterales y son responsables de una elevada proporcion de bacteriemias en los hospitales de Mexico, se propone una estrategia de control mediante la vigilancia microbiologica de las soluciones en uso. MATERIAL Y METODOS. Hospital de ensenanza de segundo nivel con 193 camas. Atiende principalmente pacientes de escasos recursos. En 1992 se inicio la vigilancia de la esterilidad de las soluciones parenterales en los servicios pediatricos mediante cuatro estrategias: durante la primera etapa se cultivo el total de soluciones en uso. Durante la segunda se cultivaron muestras aleatoriamente elegidas. Tercera y cuarta etapas con muestreo controlado y dirigido, respectivamente. RESULTADOS. Se han cultivado 1940 infusiones. Se ha observado una reduccion de la tasa de contaminacion (de 29.6% en 1992 a 12.9% en 1997, p< 0.001). Asimismo se redujo la proporcion de bacilos gramnegativos aislados en sangre (72.7% vs 40.85%, p< 0.001) y las bacteriemias nosocomiales primarias (BNP) (3.12 vs 1.54 por 100 egresos, p< 0.0001). CONCLUSIONES. La deteccion de contaminantes senala posibles fallas en el manejo parenteral, areas de riesgo y pacientes potencialmente afectados. El programa permite estudiar el nivel endemico de contaminacion de infusiones y limitar los brotes de bacteriemias nosocomiales primarias a un costo bajo.