Antimicrobial efficacy of chlorine agents against selected oral pathogens

OBJECTIVES

Method-dependent comparison of antimicrobial agents' efficacy against oral pathogens.

MATERIALS AND METHODS

Several sodium hypochlorite solutions (NaOCl)-Perisolv®, Carisolv® and Dakin's solution-were equated with chlorhexidine (CHX) and hydrogen peroxide (H2O2) against ten oral micro-organisms related to caries and periodontitis using different minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) techniques. Agents were adjusted to the final 70 mmol/L concentration of active chlorine molecule.

RESULTS

Apart from H2O2 and the amino acids of Perisolv®, all the agents revealed an antimicrobial effect. Agar diffusion test ranked CHX (p < 0.05) as the most effective against all ten specimens, followed by the NaOCl of Perisolv® and Dakin's solution. Correspondingly, in broth microdilution on agar, CHX was the most effective in eradicating micro-organisms at 0.03 mmol/L compared with 2.2 mmol/L of Dakin's solution. In contrast, the bactericidal concentration of Dakin's solution was the most effective at 0.2 mmol/L, (p < 0.001), followed by Perisolv® (2.14 mmol/L), CHX (2.38 mmol/L) and Carisolv® (3.33 mmol/L) after 5 and 10 min in broth dilution test. In live/dead analysis, 60-min exposure to a 2-fold concentration of agents resulted in two-log Aggregatibacter actinomycetemcomitans inhibition by CHX (35 mmol/L) whilst Streptococcus mutans was more susceptible, in 0.8 and 8.8 mmol/L, after 10 min to CHX and Dakin's respectively.

CONCLUSION

Replacement of CHX with tested hypochlorite agents showed evident potential and promoted rapid antimicrobial effect.

CLINICAL RELEVANCE

Effective antimicrobial agents are crucial in controlling pathogen-induced oral infections increasing clinical possibilities to combat oral biofilms. Additionally, CHX substitution with hypochlorite agents could eliminate CHX's adverse effects.

Quantifying exposure to chlorhexidine from decontamination of peripheral intravenous injection ports

BACKGROUND

Annually, almost 2 billion peripheral intravenous cannulas (PIVCs) are placed worldwide. In response to concerns of infectious complications, chlorhexidine is increasingly utilised for maintenance decontamination of PIVC injection ports. Concomitantly, the allergenic potential of chlorhexidine exposures has been highlighted by several case reports, implicating it as a trigger when used for this seemingly innocuous process. Given how widespread this application is, elucidating potential chlorhexidine exposure is needed to gauge its risks and benefits.

OBJECTIVE

To examine and quantify if chlorhexidine is entrained when used for PIVC injection port cleaning.

METHODS

Twenty benchtop PIVC set-ups were cleaned with 2% chlorhexidine and 70% alcohol wipes, following three different pragmatic protocols. Each set-up was injected with 10 ml ultrapure water, and samples tested by liquid chromatography-electrospray tandem mass spectrometry for entrained chlorhexidine.

RESULTS

Chlorhexidine was detected in every sample. Mean concentrations and standard deviations from each protocol were 41.47 ppb (4.08), 54.76 ppb (17.46), and 65.84 ppb (7.01). One-way ANOVA indicated a statistical difference between at least two groups (df = 2, F = 24.11, p < .00001), with Tukey's testing verifying significantly different mean concentrations between all groups (p < .01).

CONCLUSIONS

Using 2% chlorhexidine and 70% alcohol swabs to decontaminate PIVC injection ports resulted in consistent entrainment of chlorhexidine, with varying amounts correlated to how it was applied. These results validate case reports attributing anaphylactic/allergic reactions to suspected intravenous chlorhexidine entrainment and should factor into future risk-benefit assessments for its use in PIVC maintenance antisepsis policies and protocols.

Review of allergic reactions from use of chlorhexidine on medical products in clinical settings over 40 years: Risks and mitigations

Chlorhexidine is an antimicrobial agent widely used for infection prevention in medical settings. Nevertheless, allergic reactions ranging from mild to severe have been reported following its use. In this review, we analyzed all case reports published between the introduction of chlorhexidine and the end of 2019 for allergic responses associated with the use of medical devices and or other medical products containing chlorhexidine (CHX) to ascertain the prevalence of severe CHX allergic reactions and what practices might best mitigate those risks.In total, 77 publications containing 124 reported cases of allergic reactions were grouped into 3 product categories, catheters, semisolids, and fluid products. The country, type of reaction, route of sensitization, allergy confirmation, and intervention or mitigation was extracted for each case. Overall, 30 cases were associated with catheters, 46 cases were associated with semisolid products, and 48 cases were associated with the use of other medical products. Severe cases were managed with intravenous fluids, steroids, and epinephrine (adrenaline). None of the reported cases were fatal. The allergy risks can be mitigated by better warning and training clinicians and by recording and screening patient histories for CHX presensitization from prior exposure. For patients undergoing pre-use blood tests, IgE antibody screens can also be performed. Finally, as a precaution in the event a rare severe allergic reaction occurs, procedure carts and rooms can be prestocked with injectable epinephrine and other rapidly acting anti-inflammatory medications.