Absorption and tolerability of aqueous chlorhexidine gluconate used for skin antisepsis prior to catheter insertion in preterm neonates.

OBJECTIVE: To assess chlorhexidine absorption and skin tolerability in premature infants, following skin antisepsis with 2% aqueous chlorhexidine gluconate (CHG) prior to peripherally inserted central catheter (PICC) placement. STUDY DESIGN: Neonates less than 32 weeks gestation had skin cleansed with CHG prior to PICC placement. CHG concentrations were measured on serial blood samples. Skin integrity was evaluated for 2 weeks after CHG exposure. RESULT: Twenty infants were enrolled; median gestational age was 28 2/7 weeks (range 24 3/7 to 31 4/7). Ten infants had detectable serum chlorhexidine concentrations (range 1.6 to 206 ng ml(-1)). Seven of these infants had their highest serum concentration 2 to 3 days following exposure. No CHG-related skin irritation occurred in any infant. CONCLUSION: CHG was detected in the blood of preterm infants receiving CHG skin antisepsis for PICC insertion. Highest serum concentrations occurred 2 to 3 days after exposure. Further investigation is needed to determine the clinical relevance of CHG absorption in preterm infants.

Development of a HPLC/MS/MS method for simultaneous determination of tinidazole, dyclonine and chlorhexidine in rat plasma and its application in the pharmacokinetic research of a film-forming solution.

A rapid and sensitive HPLC/MS/MS method was developed and validated for simultaneous determination of tinidazole, dyclonine and chlorhexidine, the three main components of a film-forming solution, in rat plasma. The plasma samples were pretreated by solid phase extraction (SPE) method. Separation was achieved on a Phenomenex Gemini C(18) column (50 mm × 2.0 mm, 5 µm) using an isocratic mobile phase system composed of methanol-ammonium formate (10 mM)-formic acid (56:44:0.2, v/v/v) (pH 3.5) at a flow rate of 0.2 mL/min. Analytes were determined by tandem mass spectrometry with electrospray positive ionization and multiple-reaction monitoring (MRM) mode. The monitoring ions were (m/z) 247.4 → (m/z) 81.9 for tinidazole, (m/z) 290.1 → (m/z) 97.8 for dyclonine, (m/z) 505.0 → (m/z) 335.3 for chlorhexidine and (m/z) 282.1 → (m/z) 212.0 for phentolamine (internal standard). The calibration curves were linear in the range of 2-1000 ng/mL for the three components. The precision and accuracy of the method were well within the generally accepted criteria for biomedical analysis. It has been successfully applied to the pharmacokinetic research of a film-forming solution in rat.

Quantitative analysis of skeletal symmetric chlorhexidine in rat plasma using doubly charged molecular ions in LC-MS/MS detection.

BACKGROUND: The skeletal symmetric structure of chlorhexidine predicts that each doubly charged molecular ion may generate two para-chlorbenzenguanidines daughter ions through bond cleavage at two protonation sites, thus generating better sensitivity in MRM transition than that involving singly charged molecular ions. This unique nature can be used to improve sensitivity of a LC-MS/MS method. RESULTS: High-throughput LC-MS/MS was developed and validated to quantify chlorhexidine in rat plasma as low as 0.500 ng/ml. In the method, a unique chromatographic method on a narrow bore column reduced run time to 2.5 min and successfully minimized high background from accumulation of endogenous compounds in matrix on the column. CONCLUSION: This method was proved to be robust and suitable to support rat dermal toxicology studies.

Blood concentrations of chlorhexidine in hospitalized children undergoing daily chlorhexidine bathing.

We collected serial blood samples from children in the intensive care unit who underwent daily bathing with 2% chlorhexidine gluconate (CHG)-impregnated cloths. Low concentrations of CHG were detected in a few blood samples, indicating absorption through intact skin. There was no suggestion that CHG accumulated in the blood with repeated exposures.

Acute pulmonary toxic effects of chlorhexidine (CHX) following an intratracheal instillation in rats.

Chlorhexidine (CHX) is a cationic biguanide compound that has been widely used for disinfection of skin, mucous membranes, and medical instruments. Poisoning has been occurred occasionally due to its easy accessibility. Some fatal cases developed acute respiratory distress syndrome (ARDS) from aspiration of CHX directly into the lung. There is no preclinical information about the pulmonary toxicity of CHX available since the products of CHX are usually developed for disinfection by topical use. In this study, the acute pulmonary toxic effects of CHX following an intratracheal instillation in rats were investigated. Rats were exposed either to CHX at concentrations of 0.02% and 0.2% or to distilled water at a volume of 500 µl/kg b.w. CHX at concentration of 0.2% caused changes in hematological and biochemical values including white blood cell count (WBC), total protein (TP), albumin (ALB), lactate dehydrogenase (LDH), blood urea nitrogen (BUN) and creatinine (CRE), and induced inflammatory reactions including intra-alveolar edema and hemorrhages, as well as resulted in the target organ concentration in lungs at the level of about 1.0 µg/g and maintained for more than 1 week, when administered intratracheally in rats. The cytotoxic action of CHX might induce those detrimental reactions in rats.

Pilot trial to compare tolerance of chlorhexidine gluconate to povidone-iodine antisepsis for central venous catheter placement in neonates.

OBJECTIVE: The purpose of this pilot trial was to determine whether rates of contact dermatitis following cutaneous antisepsis for central catheter placement were similar among neonates treated with chlorhexidine gluconate and povidone-iodine. Chlorhexidine gluconate absorption was also evaluated. STUDY DESIGN: Infants weighing > or =1500 g and > or =7 days of age were randomized to a 10% povidone-iodine or 2% chlorhexidine gluconate site scrub before catheter placement. Primary outcomes evaluated included dermatitis, catheter colonization and chlorhexidine gluconate absorption. RESULT: A total of 48 neonates were enrolled. Colonization rates were similar among treatment groups (P<0.6). Dermatitis did not occur at chlorhexidine gluconate (central catheters, n=24; peripheral catheters, n=29) sites. Seven neonates had measurable chlorhexidine gluconate concentrations (range 13 to 100 ng ml(-1)) during catheterization. CONCLUSION: In this small trial chlorhexidine gluconate antisepsis was tolerated by study neonates. Chlorhexidine gluconate was cutaneously absorbed. Larger trials are needed to determine efficacy and tolerance of chlorhexidine gluconate in neonates.

High-performance liquid chromatographic determination of chlorhexidine in whole blood by solid-phase extraction and kinetics following an intravenous infusion in rats.

This paper presents the extraction and analysis of chlorhexidine (CHX) from whole blood using solid-phase extraction (SPE) together with high-performance liquid chromatography (HPLC). Blood samples, spiked with chlorpromazine used as an internal standard, were fortified with sodium acetate buffer and purified with Bakerbond C(18) SPE columns. The columns were washed, dried, and eluted with experimental optimized solvent systems. The HPLC was performed using a Capcell Pak C(18) MG column (4.6 x 250-mm) and monitored at 260 nm, using a UV detector. A mobile phase consisting of acetonitrile/water (40:60 v/v), containing 0.05% trifluoroacetic acid, 0.05% heptafluorobutyric acid, and 0.1% triethylamine, was employed. The assay was linear over the range of 0.05 to 2.0 microg/g and the limit of detection was 0.01 microg/g for CHX in whole blood. At the concentration range of 0.05 to 2.0 microg/g, the recoveries ranged from 72% to 85%, and the intra- and interday precision, expressed as coefficient of variation, were less than 11% and 13%, respectively. Kinetic characteristics following an intravenous infusion of a CHX product, Maskin solution, at a dose of 15 mg/kg in rats were evaluated using the present method. The kinetic profiles of CHX conformed to a two-compartment model with an alpha half-life (of distribution) at 0.05 h and a beta half-life (of elimination) at 0.55 h in rats. The method is simple and reliable for the determination of CHX in blood samples and could be expected to apply to forensic and clinical specimens.

A randomized controlled trial of the impact of chlorhexidine skin cleansing on bacterial colonization of hospital-born infants in Nepal.

BACKGROUND: Chlorhexidine skin cleansing might substantially reduce neonatal infection and mortality in developing countries. Few data exist on the impact of chlorhexidine cleansing on skin colonization of infants during the first day of life or on the absorption potential of chlorhexidine during newborn skin cleansing. METHODS: Hospital-born newborns in Kathmandu, Nepal were randomly allocated to full-body skin cleansing with 0.25%, 0.50%, or 1.00% chlorhexidine solution. Skin swabs were collected from the axilla, inguinal, and peri-umbilical areas before cleansing (baseline), and at 2 and 24 hours after treatment. Skin flora was quantified and organisms identified. In a subsample, heel prick blood was collected 24 hours after the cleansing and percutaneous absorption of chlorhexidine was assessed. RESULTS: Among 286 enrolled newborns, no adverse effects on skin were reported and body temperature was minimally reduced (mean reduction, 0.33 degrees C). In all groups, positive skin culture rates were significantly reduced at 2 hours but generally not at 24 hours; greater reductions were observed with higher concentrations of chlorhexidine. Effect at 24 hours was highest in the 1.00% group (37% lower positive skin culture rate). For 15 of 75 infants with heel pricks, chlorhexidine was detected at trace concentrations (<8 ng/mL, n = 14; 25.8 ng/mL, n = 1). CONCLUSIONS: Chlorhexidine skin cleansing seemed safe and reduced skin flora in newborns in a dose-dependent manner 2 hours after treatment. Greater residual effect at the highest concentration (1%) might provide broader benefit and may simplify combined maternal and neonatal regimens by matching the concentration used for vaginal cleansing during labor.

Determination of chlorhexidine (CHD) and nonylphenolethoxylates (NPEOn) using LC-ESI-MS method and application to hemolyzed blood.

Rapid and reliable methods for identification of chlorhexidine (CHD) and nonylphenolethoxylates (NPEOn) in antiseptic and hemolyzed blood using electrospray ionization mass spectrometry (ESI-MS) were developed. Fragmental analysis provides accurate evidence for the presence of CHD in the samples. For the determination of CHD in hemolyzed blood, the method was also developed using LC-ESI-MS. Linearity of calibration curve was obtained over the concentration range of 0.1-11 microg/mL with residuals from -4.3 to 6.7%. We applied the methods to the case of suicidal injection of antiseptic and successfully detected CHD and NPEOn from hemolyzed blood. The CHD concentration was 352 microg/mL.

Tolerance and safety of different concentrations of chlorhexidine for peripartum vaginal and infant washes: HIVNET 025.

BACKGROUND: There is a continuing need to evaluate sustainable interventions for prevention of mother-to-child transmission (MTCT) of HIV type 1. We evaluated different concentrations (0.25%, 1%, and 2%) of chlorhexidine (CHX) for perinatal maternal and infant washes to identify the maximum tolerable concentration of CHX for such an intervention. METHODS: Women were enrolled during their third trimester at the maternity unit of the Chris Hani Baragwanath Hospital in Soweto, South Africa, and perinatal maternal and infant washes were completed. Subjective maternal symptoms as well as infant examinations were used to assess tolerability of the washes. RESULTS: The 0.25% concentration of CHX was well tolerated by the mothers (n = 29). Ten of 79 women (13%) with 1% CHX washes complained of mild vaginal area burning or itching, and washes were stopped in 5 (6%). Twenty-three of 75 women (31%) in the 2% CHX wash group had subjective complaints, and the washes were stopped in 12 (16%). There were no clinical indications of toxicity of the CHX washes among infants. CONCLUSION: A 1% solution of CHX appears to be a safe and tolerable concentration of CHX for consideration in an MTCT prevention trial.

Toxicological analysis of chlorhexidine in human serum using HPLC on a polymer-coated ODS column.

A simple and reliable high-performance liquid chromatographic (HPLC) method for analyzing chlorhexidine in human serum was developed. After the addition of an internal standard, levomepromazine, 0.2 mL serum was deproteinized with 10% perchloric acid. The acidic supernatant was neutralized with 1M potassium carbonate solution, and the insoluble salt was removed by centrifugation. An aliquot of the supernatant was applied to HPLC with UV detection (260 nm). HPLC separation was achieved on a polymer-coated ODS column equilibrated with acetonitrile/water containing 0.05% trifluoroacetic acid, 0.05% heptafluorobutyric acid, and 0.1% triethylamine (40:60, v/v). The calibration curve was linear in the concentration range from 0.05 to 50.0 microg/mL, and the lower limit of detection was 0.05 microg/mL. The accuracy and precision of the method were evaluated at concentrations of 0.5 microg/mL and 5.0 microg/mL. The coefficients of variation ranged from 4.0 to 4.5%. The concentration of chlorhexidine in the serum of a patient who died after a suspected intravenous injection of chlorhexidine gluconate was determined.

Safety and efficacy of an improved antiseptic catheter impregnated intraluminally with chlorhexidine.

The safety and efficacy of a second-generation improved antiseptic catheter impregnated with silver sulfadiazine and increased levels of chlorhexidine on its outer surface and chlorhexidine alone on its luminal surfaces was compared in vitro and in vivo to standard antiseptic catheters impregnated with these antimicrobials on their outer surfaces only. In rat and pig intravenous models, the improved antiseptic catheter was significantly more effective in resisting both outer surface and luminal colonization compared with the standard antiseptic or control catheters. There was no evidence of tissue toxicity in any group.

The incidence of IgE and IgG antibodies to chlorhexidine.

IgE antibodies to the antiseptic agent chlorhexidine have recently been detected in the majority of sera from a small group of predominantly Japanese individuals showing anaphylactic-type adverse reactions towards chlorhexidine. In this study the prevalence of IgE and IgG antibodies with specificity for chlorhexidine was investigated in groups of Japanese and British individuals. The RAST data, using a better defined semi-chlorhexidine-HSA antigen than previously employed, revealed that chlorhexidine-specific IgE was only detected in Japanese individuals who had experienced anaphylactic-type reactions and was not detected in groups of Japanese nurses and patients, or in groups of British nurses and hospital staff, all in regular contact with chlorhexidine. A group of British blood donors was also negative. In contrast, IgG antibodies were detected not only in sera from chlorhexidine-sensitive Japanese patients, but also in several sera from Japanese nurses, non-sensitive Japanese patients and several British individuals. The possible reasons for these observations are discussed.

Sensitive high-performance liquid chromatographic method for the determination of chlorhexidine in human serum and urine.

A high-performance liquid chromatographic method for the analysis of chlorhexidine in human serum and urine was developed. Chlorhexidine and the internal standard, chlorpheniramine, were extracted into chloroform, containing 5% 2-propanol, and back-extracted into dilute sulfuric acid. Chromatographic separation was achieved on a C18 column equilibrated with methanol-water (70:30, v/v), containing 0.005 M sodium heptane-sulfonate. The sensitivity of the assay was 20 ng/ml of biological matrix, using 0.5-ml samples. The application of this method to monitor chlorhexidine levels in burn patients treated topically with a chlorhexidine-containing burn cream was demonstrated.

Comparison of hexachlorophane and chlorhexidine powders in prevention of neonatal infection.

The protective effect of treating the skin of newborn infants with powders containing 1% chlorhexidine or 0.33% hexachlorophane was compared. Each was equally effective in preventing colonisation and infection by Staphylococcus aureus. In contrast, the skin became profusely colonised by coagulase-negative staphylococci, irrespective of the powder used. Venous blood concentrations of chlorhexidine were low or undetectable in the few infants whose blood was analysed.

Absorption of chlorhexidine from the intact skin of newborn infants.

34 newborn infants who had been bathed in a standard manner with Hibiscrub were studied to find out whether it was absorbed percutaneously. Low levels of chlorhexidine were found in the blood of all 10 babies sampled by heel prick, and 5 of 24 from whom venous blood was taken. The detection of chlorhexidine varied greatly with the method and timing of sampling, and no correlation was found between gestational or postnatal age and chlorhexidine levels.

A method for the analysis of chlorhexidine in serum.

A colorimetric method for the determination of chlorhexidine in serum or plasma has been elaborated; the limit of detection of the method is 25 ng/ml, based on 10 ml of serum or plasma.