Chlorhexidine Keratitis: Safety of Chlorhexidine as a Facial Antiseptic

Continuous Corneal Endothelial Damage by Chlorhexidine Alcohol Used for Disinfection in Nonophthalmic Surgery

PURPOSE

To report a case of corneal endothelial damage caused by alcohol-containing chlorhexidine gluconate (CG-A) and its progression over time.

METHODS

This was a case report.

RESULTS

A 22-year-old man underwent neurosurgery under general anesthesia. CG-A (1%) was used for disinfection after the application of corneal protection tape. Postoperatively, the patient presented with hyperemia and swelling of the left conjunctiva and was referred to our department. Initial examination revealed left corneal epithelial erosion and corneal edema, which improved on postoperative day 14. The corneal endothelial cell density (ECD) was 3,345 cells/mm 2 on day 14, decreased rapidly to 2,090 cells/mm 2 on day 42, and slowly reduced to 1,122 cells/mm 2 on day 168. Thereafter, no decrease in ECD was observed.

CONCLUSIONS

CG formulations can lead to a persistent decrease in ECD over several months, even after improvement of acute corneal edema.

Small animal patient preoperative preparation: a review of common antiseptics, comparison studies, and resistance

This review aims to describe commonly used antiseptics in veterinary medicine including their mechanism of action, spectrum of activity, potential adverse effects, and application techniques. Additionally, it provides a review of the veterinary literature comparing antiseptics, a discussion of effectiveness and efficacy studies, and the potential for increased resistance to biocides and antimicrobials. This review concludes that appropriate selection and use is necessary to prevent the occurrence of surgical site infections, adverse effects, and potential for increasing resistance to antimicrobials. Continued research is needed to fill gaps in the current knowledge such as optimal preparation procedures for various surgical sites, standardization of efficacy and effectiveness testing, and the clinical impact of decreased susceptibility to chlorhexidine and other antiseptics.

New Approaches to Overcoming Antimicrobial Resistance in Endophthalmitis

Endophthalmitis is a rare but vision-threatening infection characterized by marked inflammation of intraocular fluids and tissues, uncommonly seen following surgery and intravitreal injection. Antimicrobials are used worldwide in the prophylaxis and treatment of bacterial and fungal infections of the eye and are standard treatment in the preoperative and postoperative care of surgical patients. However, antimicrobials are reported to be overprescribed in many parts of the world, which contributes to antimicrobial resistance (AMR). AMR complicates the prophylaxis and treatment of endophthalmitis. This article examines the prevalence and mechanisms of AMR in ocular microorganisms, emphasizing the importance of understanding AMR patterns for tailored treatments. It also explores prophylaxis and management strategies for endophthalmitis, with a discussion on the use of intracameral antibiotic administration. The use of prophylactic intracameral antibiotics during cataract surgery is common in many parts of the world but is still controversial in some locations, especially in the US. Finally, it highlights the role of stewardship in ophthalmology and its benefits in the treatment of endophthalmitis.

Periocular and ocular surface nonmelanoma skin cancer

Periocular and ocular surface nonmelanoma malignancies, including basal cell carcinoma (BCC), squamous cell carcinomas (SCC), and ocular surface squamous neoplasia (OSSN), are rare, but their management requires special considerations. The most common periocular malignancy is BCC, which constitutes 80% to 96% of tumors, followed by SCC, which represents 5% to 10% of tumors. OSSN represents a spectrum of diseases that encompass dysplastic alteration to the squamous epithelium of the eye. OSSN ranges from squamous dysplasia to conjunctival intraepithelial neoplasia/carcinoma in situ to invasive SCC, which is the most common ocular malignancy. These tumors can be staged using the eighth edition of the American Joint Committee on Cancer categorization system. The standard of care for periocular malignancies is Mohs micrographic surgery, while medical management with 5-fluorouracil (5-FU), interferon alfa-2b (INF), and mitomycin C (MMC) or "no touch" surgical excision are options for OSSN. Systemic therapies, including sonic hedgehog inhibitors for BCC and epidermal growth factor inhibitors and immune-checkpoint inhibitors for SCC, can be utilized for advanced disease. Recurrence rates are higher for periorbital and ocular malignancies than their respective cutaneous counterparts. These carcinomas and their respective treatments have unique side effects and considerations in an effort to preserve visual function.

Three Consecutive Cases of Ocular Polyhexamethylene Biguanide (PHMB) Toxicity Due to Compounding Error

Acanthamoeba keratitis is treated with long-term biguanide therapy, and the treatment itself can lead to ocular side effects. Knowledge of possible toxic complications can help in the better titration of the treatment regimen. Here, we describe the toxic side effects of polyhexamethylene biguanide (PHMB), which occurred in three consecutive patients treated with in-house compounded PHMB. There was an error in compounding the solution, with the resultant concentration of PHMB being around 0.2%. Patients developed ocular toxicity like conjunctival inflammation, persistent epithelial defect, and large pigment clumps on endothelium within six weeks of initiation of therapy. All of them developed rapidly progressive cataract and mydriatic pupil within three months. PHMB has the potential to cause irreversible damage to ocular structures, and the toxicity is time and concentration-dependent.

Arthrocentesis and soft tissue aspiration and injection

Accessing a joint with a needle (arthrocentesis) to extract synovial fluid is a skill intrinsic to the rheumatologist's praxis. Joint aspirations are essential for diagnosing or excluding septic joints, are the gold standard for diagnosing acute crystal arthritis, and can provide valuable information about the nature of other forms of arthritis. In appropriate settings, injecting medications into joints can provide rapid, temporary, or even prolonged relief of pain and swelling and can provide a window of relief until other treatment modalities (anti-inflammatories, immunomodulators, and physical therapy) can enforce durable responses. Soft tissue aspirations (e.g., of bursae) and soft tissue injections (of bursae, tendons, trigger points, and areas of nerve compression) can provide similar relief, earning the practitioner the gratitude of the patient. Here, we provide a primary on joint and soft tissue aspiration and injection, including indications for and against procedures, preparing for procedures, and approaches to specific musculoskeletal structures.

Evaluation of the role of povidone‑iodine in the prevention of surgical site infections

Background

The occurrence of surgical site infections (SSIs) is associated with increased risk of mortality, development of other infections, and the need for reintervention, posing a significant health burden. The aim of this review was to examine the current data and guidelines around the use of antiseptic povidone‑iodine (PVP-I) for the prevention of SSIs at each stage of surgical intervention.

Methods

A literature search for selected key words was performed using PubMed. Additional papers were identified based on author expertise.

Results

Scientific evidence demonstrates that PVP-I can be used at every stage of surgical intervention: preoperative, intraoperative, and postoperative. PVP-I is one of the most widely used antiseptics on healthy skin and mucous membranes for preoperative surgical site preparation and is associated with a low SSI rate. For intraoperative irrigation, aqueous PVP-I is the recommended agent and has been demonstrated to decrease SSIs in a range of surgical settings, and for postoperative wound healing, there is a growing body of evidence to support the use of PVP-I.

Conclusions

There is a need for more stringent study designs in clinical trials to enable meaningful comparisons between antiseptic agents, particularly for preoperative skin preparation. The use of a single agent (PVP-I) at each stage of surgical intervention could potentially provide advantages, including economic benefits, over agents that can only be used at discrete stages of the surgical procedure.

Key message

Evidence supports the use of PVP-I at all stages of surgical intervention, from preoperative measures (including skin preparation, preoperative washing, and nasal decolonization) to intraoperative irrigation, through to postoperative wound management. However, there is a need for more stringent study designs in clinical trials to enable meaningful comparisons between antiseptic agents, particularly for preoperative skin preparation.

Evaluation of Environmental Stability and Disinfectant Effectiveness for Human Coronavirus OC43 on Human Skin Surface

The environmental stability of human coronavirus OC43 (HCoV-OC43) on the surface of human skin and the effectiveness of disinfectant against HCoV-OC43, which are important to prevent contact transmission, have not been clarified in previous studies. Using previously generated models, we evaluated HCoV-OC43 stability and disinfection effectiveness. Then we compared the results with those for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The median survival time of HCoV-OC43 on the surface of human skin was 24.6 h (95% confidence interval, 19.7 to 29.6 h), which was higher than that of SARS-CoV-2 (10.8 h). Although the in vitro disinfectant effectiveness evaluation showed that HCoV-OC43 has a higher ethanol resistance than SARS-CoV-2, HCoV-OC43 on the skin surface was completely inactivated by a minimum of 50% ethanol within 5 s (the log reduction values were >4.0). Moreover, 1.0% chlorhexidine gluconate and 0.2% benzalkonium chloride showed relatively high disinfectant effectiveness, and the log reduction values when these disinfectants were applied for 15 s were >3.0. HCoV-OC43 is highly stable on the skin surface, which may increase the risk of contact transmission. Although HCoV-OC43 has relatively high ethanol resistance, appropriate hand hygiene practices with current alcohol-based disinfectants sufficiently reduce the risk of contact transmission. IMPORTANCE This study revealed the environmental stability of HCoV-OC43 and disinfectant effectiveness against HCoV-OC43, which had not been demonstrated in previous studies. HCoV-OC43 is highly stable on the surface of human skin, with a survival time of approximately 25 h. High stability of HCoV-OC43 may increase the risk of contact transmission. Furthermore, the in vitro disinfectant effectiveness evaluation showed that HCoV-OC43, which is classified as an envelope virus, has a relatively high ethanol resistance. This finding suggests that disinfectant effectiveness may vary greatly depending on the virus and that each virus targeted for infection control should be evaluated individually. HCoV-OC43 on the skin surface was rapidly inactivated by 50% ethanol, which suggests that appropriate hand hygiene practices with current alcohol-based disinfectants can sufficiently reduce the risk of HCoV-OC43 contact transmission.

Evaluation of the Residual Disinfection Effects of Commonly Used Skin Disinfectants against Viruses: An Innovative Contact Transmission Control Method

Lasting disinfection effects, that is, the residual disinfection effects (RDEs), of skin-coated disinfectants have rarely been considered for infection control owing to the challenges involved in the accurate evaluation of RDEs. In this study, we constructed a new skin evaluation model and determined the RDEs of existing disinfectants against viruses. Our results showed that ethanol and isopropanol had no RDE, whereas povidone-iodine, chlorhexidine gluconate, and benzalkonium chloride (BAC) exhibited RDEs, with 10% povidone-iodine and 0.2% BAC showing particularly strong RDEs. The RDE of 0.2% BAC was strong enough to reduce the median survival times of severe acute respiratory syndrome coronavirus-2, human coronavirus-OC43, and influenza virus from 670 to 5.2, 1300 to 12, and 120 to 4.2 min, respectively. Additionally, this strong RDE was maintained even 4 h after coating the skin. Clinical data also showed that the strong RDE of 0.2% BAC was maintained for more than 2 h. Thus, applying disinfectants with strong RDEs on the skin correlates with a reduction in virus survival time and appears to create a skin surface environment that is not conducive to virus survival. A prolonged reduction in virus survival decreases the contact transmission risk, thereby enabling stronger infection control.

Fusarium Keratitis-Review of Current Treatment Possibilities

In many parts of the world, fungi are the predominant cause of infectious keratitis; among which, Fusarium is the most commonly isolated pathogen. The clinical management of this ophthalmic emergency is challenging. Due to the retardation of the first symptoms from an injury and the inability to differentiate fungal from bacterial infections based on clinical symptoms and difficult microbial diagnostics, proper treatment, in many cases, is postponed. Moreover, therapeutical options of Fusarium keratitis remain limited. This paper summarizes the available treatment modalities of Fusarium keratitis, including antifungals and their routes of administration, antiseptics, and surgical interventions.

Comparison of Skin Antiseptic Agents and the Role of 0.01% Hypochlorous Acid

BACKGROUND

Hypochlorous acid (HA) has both anti-microbial and wound-healing properties with a growing role for utilization in pre-procedural care on the face.

OBJECTIVES

The authors sought to compare the antiseptic property of 0.01% HA solution, 5% povidone iodine (PI), 4% chlorhexidine gluconate (CHG), and 70% isopropyl alcohol (IPA) antiseptic on facial skin.

METHODS

This was a prospective single-center clinical trial.

RESULTS

A total of 21 participants were recruited. Bacterial growth was seen in CHG (10%), IPA (71%), PI (81%), and HA (95%) of specimens (P < 0.001). CHG had less growth compared with HA (P = <0.001), IPA (P = <0.001), and PI (P = <0.001). No difference in bacterial growth was noted between HA and IPA (P = 0.063) or HA and PI (P = 0.25). Significant differences in mono-microbial and poly-microbial growth were seen between HA and IPA (P = 0.046) and HA and CHG (P = <0.001). Staphylococcus epidermidis grew less frequently in CHG (10%), followed by IPA (29%), PI (71%), and HA (71%). Staphylococcus capitis grew less frequently in CHG (0%), followed by PI (14%), HA (24%), and IPA (29%).

CONCLUSIONS

CHG reduced the bacterial growth compared with HA, PI, and IPA. However, HA, PI, and IPA had insignificant differences in bactericidal effects. Our study provides a supporting role of HA to be considered as an antiseptic.

LEVEL OF EVIDENCE: 2

Review: Perspective on ocular toxicity of presurgical skin preparations utilizing Chlorhexidine Gluconate/Hibiclens/Chloraprep

Background:

Chlorhexidine Gluconate (CHG), Hibiclens (4% CHG with 4% Isopropyl Alcohol Detergent), and Chloraprep (i.e. labeled CHG-based solutions), utilized as preoperative surgical preparatory solutions may all cause severe oculotoxicity and ototoxicity. Alternatively, 10% Povidone-Iodine (PI) solutions without detergent demonstrate minimal toxic effects on the eyes and ears.

Methods:

Based on studies from 1984 to 2021, we compared the safety/efficacy of CHG-based versus PI-based solutions utilized for presurgical skin preparation near the cornea/eyes and ears (i.e., predominantly for cranial or cervical spine surgery).

Results:

Some studies documented that even minimal exposure (i.e., “splash risk”) during face/neck skin preparation with CHG-based solutions could result in irreversible corneal injury and ototoxicity. Within minutes to hours, CHG-based non-detergent solutions posed the risks of; corneal epithelial edema, anterior stromal edema, conjunctival chemosis, bullous keratopathy, and de-epithelialization. Notably, even occlusive dressings like Tegaderm could not protect against CHG penetration. Alternatively, PI-based solutions posed no to minimal ocular and/or ototoxicity, while often demonstrating comparable protection against surgical site infections (SSI).

Conclusion:

Chlorhexidine Gluconate (CHG), Hibiclens, and Chloraprep (i.e. CHG-based solutions) are often used as skin preparations near the face/eyes/spine (i.e., particularly anterior/posterior cervical procedures). However, if these solutions come in contact with the eyes, corneal irritation, abrasions, and even blindness may result. Alternatively, PI non-detergent solutions demonstrate safety/minimal oculotoxicity/ototoxicity, while frequently showing comparable efficacy against SSI.

Review, analysis, and education of antiseptic related ocular injury in the surgical settings

Preoperative skin antiseptic preparation is the gold standard for prevention of surgical infection. However, improper use of antiseptics may lead to severe ocular damage. Currently, the most common surgical antiseptics can be divided into aqueous-based and alcohol-based disinfectants, with chlorhexidine and iodine/iodophors being the two major components. Chlorhexidine has a persistent antimicrobial effect and is resistant to neutralization by blood or organic products in surgical wounds. Nevertheless, due to its toxicity to the ears, meninges, and eyes, application of chlorhexidine should be prohibited in these surgical fields. Iodine/iodophor is better tolerated by the ocular surface and is the recommended antiseptic for ophthalmic or head and neck surgeries close to the periocular area. Alcohol is less pricey and has a rapid antiseptic effect, though its desiccating effect and flammability restrict the use in mucosal or laser surgeries. The single or combined use of these antiseptics may inadvertently induce severe ocular damage, especially during time-consuming head and neck surgeries with prone, hyperextension, or lateral tilt positions, or surgeries under general anesthesia. Apart from the choice of antiseptics, appropriate selection and attachment of bio-occlusive dressings are key to avoiding antiseptic-related ocular injuries. In this review, we provided a comprehensive summary of the characteristics of antiseptics used in surgical settings and the possible mechanisms and outcomes of antiseptic-related ocular injuries. The prevention, diagnosis, and acute management of these complications were also discussed.

Post-injection endophthalmitis rates with reduced povidone-iodine prophylaxis in patients with self-reported iodine sensitivity

BACKGROUND

Our objectives were (1) to report the post-injection endophthalmitis rate over 18 months, and (2) to determine any difference in the incidence of endophthalmitis in patients treated with reduced or no 5% povidone-iodine (PI) due to self-reported PI sensitivity.

METHODS

We performed a retrospective cohort study of all patients who received intravitreal injections (IVIs) from January 1st, 2018 to June 26th, 2019. Information on patients' age, gender visual acuities, the number of injections, drug administered, self-reported iodine sensitivity and injection protocols were obtained from electronic and paper records. For endophthalmitis cases, vitreous culture results and treatment were also noted. Patients were divided into three cohorts based on the injection protocol used for statistical analysis.

RESULTS

During the study period 22,046 IVIs were administered to 3332 eyes of 2709 patients. Intolerance to PI was reported by 2.4% of patients. The incidence of endophthalmitis was 0.02% (4/21,185) with the standard 5% PI protocol, 0.78% (6/769) with a reduced PI protocol involving fewer drops of 5% PI and chlorohexidine 0.05% for periorbital skin cleansing, and 1.09% (1/92) without any PI use. Receiving the standard PI protocol was associated with significantly lower rates of endophthalmitis compared to both the reduced PI and no PI protocols (p < 0.0001).

CONCLUSIONS

Patients who opt for less or no PI use are likely at significantly increased risk of developing post-IVI endophthalmitis. It is imperative to educate, counsel and consent these patients accordingly while exploring alternative antiseptic solutions.

Preventing complications in dermatologic surgery: Presurgical concerns

Cutaneous surgery has become critical to comprehensive dermatologic care, and dermatologists must therefore be equipped to manage the risks associated with surgical procedures. Complications may occur at any point along the continuum of care, and therefore assessing, managing, and preventing risk from beginning to end becomes essential. This review focuses on preventing surgical complications pre- and postoperatively as well as during the surgical procedure.

Improving aseptic injection standards in aesthetic clinical practice

The rise in popularity and demand for nonsurgical injectable aesthetic procedures is inherently accompanied by an increase in reported complications, particularly those related to infection. Aseptic technique is under the control of aesthetic practitioners and can be modified to minimize the potential for cross-contamination and infection. This should be a key consideration during all clinical procedures, particularly those involving breach of the skin's natural defenses and the use of soft tissue filler. A consensus group of five UK expert aesthetic clinicians were convened to discuss current best practice for aseptic techniques in medical aesthetics. The aim of the consensus group was to recommend a step-by-step procedure to achieve optimal aseptic practice in private clinics, and define important considerations for reducing infection risk during the whole patient journey: pre-, during- and postaesthetic procedure. Recommendations were based on current evidence and extensive clinical experience. Various procedure recommendations were made to achieve and maintain a high standard of asepsis and infection control. Guidance was divided into three phases for patients and health care professionals, covering preprocedure (including patient selection), during-procedure, and postprocedure considerations. Although adherence to standard hospital guidance on handwashing and cleanliness measures is a cornerstone of controlling cross-contamination, aesthetic clinics carry a high potential risk of infection-particularly as popular treatments with dermal fillers primarily involve the face. This expert consensus guidance recommends procedures to mitigate the potential risks of asepsis.

The Use of Chlorhexidine as a Skin Preparation on the Head and Neck: A Systematic Review of Ocular and Ototoxicity

BACKGROUND

Chlorhexidine gluconate is one of the most effective surgical preparations, but it has known potential ocular and ototoxicity.

OBJECTIVE

To review reported cases of ocular and ototoxicity caused by chlorhexidine and summarize the clinical situations in which chlorhexidine toxicity occurred.

METHODS

We performed a systematic review of PubMed and the Web of Science.

RESULTS

Fourteen cases reported sensorineural hearing loss from chlorhexidine instilled into the ear. Of the 38 cases of ocular toxicity, 8 cases were caused by direct instillation in the eye and 17 involved periocular surgical preparation. In the remaining cases, the area prepped was less defined. Seven cases involved preparation of the face, 1 for the scalp, 2 cases were drips from distant sites, and 3 cases did not specify the means of exposure.

CONCLUSION

The vast majority of toxicity occurred in patients undergoing general anesthesia and was rarely seen in situations where surgery was performed by dermatologists. Ultimately, it should be up to the individual physician to decide whether chlorhexidine is the best choice for a particular outpatient procedure.

Two per cent alcoholic chlorhexidine versus alcoholic five per cent povidone-iodine for the prevention of perineural catheter colonisation: The CHLOVEPI randomised, controlled trial

BACKGROUND

Multimodal analgesia, including a regional technique using perineural catheters (PNCs), is recommended for the treatment of moderate-to-severe acute postoperative pain. Perineural catheters are at risk of bacterial colonisation. In this study, we compared the cutaneous antiseptic efficacy of 2% alcoholic chlorhexidine and povidone-iodine-alcohol for preventing the bacterial colonisation of PNCs in orthopaedic surgery.

METHODS

We performed a randomised, controlled trial, comparing two cutaneous antisepsis strategies, one based on 2% alcoholic chlorhexidine and the other on povidone-iodine-5% alcohol, for placed PNCs before orthopaedic surgery. The primary endpoint was the incidence of catheter bacterial colonisation (threshold > 1000 colony-forming units/ml). The secondary endpoints were the incidence of catheter-related infections and the adverse effects of the antiseptic solutions.

RESULTS

From November 2016 to May 2018, we included 113 patients in this study. The use of alcoholic chlorhexidine was associated with a lower incidence of catheter colonisation (15.5% (n = 9) versus 32.7% (n = 18); OR: 0.28 [0.09-0.77], p =  0.01). No catheter-related infections or adverse effects of antiseptic solutions were observed in either group. The risk factors associated with colonisation were a duration of catheter use ≥ 3 days (p =  0.04) and obesity (p = 0.005). The most frequently identified bacterium was Staphylococcus epidermidis.

CONCLUSION

Skin disinfection with 2% alcoholic chlorhexidine decreases bacterial colonisation rates for placed perineural catheters.

Facial aesthetic injections in clinical practice: Pretreatment and posttreatment consensus recommendations to minimise adverse outcomes

Facial aesthetic treatment with injectable neuromodulators and hyaluronic acid fillers is well established, with favourable safety profiles and consistent outcomes. As with any medical treatment, adverse events and complications may occur. Adverse events associated with these products are typically transient and mild to moderate in severity. Serious adverse events, such as infection and intravascular occlusion, are rare. Proper patient selection, consent and counselling, preparation and impeccable injection technique are important risk reduction strategies. Both clinicians and patients must be alert to the signs and symptoms of complications so that appropriate treatment can be started promptly. In this article, the authors review the current literature and provide their consensus recommendations for minimising adverse outcomes when treating patients with botulinum toxin or hyaluronic acid fillers.

Preoperative Considerations for the Prevention of Surgical Site Infection in Superficial Cutaneous Surgeries: A Systematic Review

Background: Surgical site infections (SSIs) pose challenges to the outcome of superficial cutaneous procedures. Objective: The objective of this study was to summarize published data regarding appropriate perioperative considerations to decrease SSI, including antiseptic use, topical decolonization, antibiotic prophylaxis, and clean versus sterile technique in superficial cutaneous procedures. A literature search was performed via PubMed and Cochrane Library by using relevant keywords. A total of 37 articles met the inclusion criteria. Strength of data was assessed according to the Oxford Centre criteria and a modified Grading of Recommendations, Assessment, Development, and Evaluation approach. Results: Chlorhexidine is the antiseptic of choice in clean or outpatient superficial cutaneous procedures. Decolonization of carriers of Staphylococcus aureus with mupirocin is warranted for all superficial cutaneous procedures. Minor procedure rooms may be considered for superficial cutaneous procedures that possess an inherently low risk of SSI. Surgeons may consider nonsterile gloves instead of sterile gloves for clean or outpatient superficial cutaneous procedures. Postoperative use of topical antibiotics may be discontinued, as there are risks of adverse effects and increasing bacterial resistance without a significant reduction in SSI. Conclusion and Relevance: This systematic review provides new and updated evidence for the prevention of SSI in superficial cutaneous procedures through antiseptic use, antibiotic use, topical agents, and the surgical environment. The overall quality of evidence is good, with most articles being original research or systematic reviews. However, there is a need for dermatologic- and plastic surgery-specific studies regarding the prevention of SSI.

Global Approaches to the Prevention and Management of Delayed-onset Adverse Reactions with Hyaluronic Acid-based Fillers

BACKGROUND

Delayed-onset adverse reactions to hyaluronic acid (HA) fillers are uncommon but have received increased attention, particularly with regard to late-onset nodules. Globally, there is a need for comprehensive prevention and management strategies.

METHODS

Experts with clinical practices in diverse regions of the world and extensive experience in managing complications related to HA fillers convened to propose and evaluate approaches to prevent delayed-onset adverse reactions after HA filler administration and manage late-onset nodules.

RESULTS

The expert panel agreed to define delayed-onset adverse reactions as those presenting more than 4 weeks posttreatment, with swelling, induration, and nodulation being the most common clinical signs. The panel recommended 5 general key approaches for the prevention of delayed-onset reactions (patient selection, anatomic location of injection/product selection, aseptic technique, injection procedure/filler, and posttreatment care). Strategies recommended for managing late-onset nodules included oral antibiotics, oral steroids, nonsteroidal anti-inflammatory drugs if needed, hyaluronidase for noninflammatory nodules (recognizing the limitations and regional availability of this treatment), intralesional antibiotics, intralesional immunosuppressive drugs such as steroids and fluorouracil, and surgical excision as a last resort. The panel noted that late-onset nodules may vary in both clinical presentation and etiology, making them challenging to address or prevent, and stressed individualized treatment based on clinical presentation. Regional differences in aseptic protocols, antibiotic selection, and steroid formulations were described.

CONCLUSION

Insights from global experts on approaches to prevent and manage delayed-onset adverse reactions following HA filler administration, including late-onset nodules, support clinicians worldwide in optimizing patient outcomes and safety.

Mohs Micrographic Surgery at Challenging Anatomical Sites

BACKGROUND

Mohs micrographic surgery (MMS) is often the treatment of choice for skin cancer removal as it maximizes normal tissue sparing and can be paired with a reconstructive approach that optimizes function and cosmesis. Many tumors on the eyelid, nose, ear, and genitals are particularly well suited for MMS but can be challenging for the dermatologic surgeon.

OBJECTIVE

To review the complex anatomy, as well as the authors' approach to executing and interpreting Mohs layers, at each of these anatomical sites.

METHODS

A review of the literature on MMS of the eyelid, nose, ear, and genitals was performed using the PubMed database and relevant search terms.

CONCLUSION

These sites present potential pitfalls for tumor resection and reconstruction, but with the proper technique, the dermatologic surgeon can minimize tumor recurrence and MMS complications. Warning signs for potentially difficult tumor resection can signify when an interdisciplinary approach is warranted.

0.01% Hypochlorous Acid as an Alternative Skin Antiseptic: An In Vitro Comparison

OBJECTIVE

Compare the in vitro efficacy of hypochlorous acid 0.01% (HA), povidone iodine 5% (PI), chlorhexidine gluconate 4% (CHG), and isopropyl alcohol 70% (IPA) against common skin microorganisms.

MATERIALS AND METHODS

Time-kill studies were conducted against methicillin-susceptible Staphylococcus aureus (MSSA) and Staphylococcus epidermidis (MSSE), methicillin-resistant S. aureus (MRSA) and S. epidermidis (MRSE), Candida albicans, Corynebacterium species (striatum and amycolatum), Propionibacterium acnes, Pseudomonas aeruginosa, Streptococcus pyogenes, Staphylococcus capitis, and Staphylococcus xylosus.

RESULTS

Methicillin-resistant S. aureus: Bactericidal effect was immediate for HA and IPA. For PI and CHG, the effect occurred at 1 and 10 minutes, respectively. Methicillin-resistant S. epidermidis: Hypochlorous acid, IPA, and PI had immediate bactericidal effects, whereas CHG required 1 minute. Methicillin-susceptible Staphylococcus aureus: All agents had bactericidal effects at 1 minute. C. species, S. pyogenes, P. aeruginosa, and P. acnes: All antiseptics demonstrated immediate bactericidal effects. Methicillin-susceptible Staphylococcus epidermidis and S. capitis: Hypochlorous acid and IPA had immediate effect, whereas PI and CHG required 1 minute. C. albicans: Hypochlorous acid, IPA, and PI were immediately bactericidal, whereas CHG required 1 minute. S. xylosus: Hypochlorous acid and CHG were immediately bactericidal, whereas IPA and PI required 1 and 2 minutes, respectively.

CONCLUSION

In vitro studies of HA 0.01% were observed to have equal or more efficacious antiseptic properties compared with IPA, CHG, and PI. Future studies will be needed to investigate its role in periocular use.

Filler Nodules: Inflammatory or Infectious? A Review of Biofilms and Their Implications on Clinical Practice

BACKGROUND

The numbers of minimally invasive cosmetic procedures performed in the United States have steadily increased each year. Concurrently, the rates of filler complications have also increased. Delayed filler reactions and granulomas have recently been attributed to biofilm infections.

OBJECTIVE

The biology and pathogenesis of biofilms, and their diagnosis, treatment, and prevention will be discussed.

METHODS

The relevant and recent literature on delayed filler reactions and biofilms was reviewed.

RESULTS

Increasing evidence implicates biofilm infections in the pathogenesis of delayed filler reactions. Therapeutic and preventative measures can be taken to minimize the occurrence of these potentially devastating consequences of dermal fillers.

CONCLUSION

Awareness of biofilm infections is key in the assessment of filler reactions in order to ensure timely and accurate diagnosis and treatment.

Systematic review of ototoxic pre-surgical antiseptic preparations - what is the evidence?

Objective

There is uncertainty regarding the safety of surgical antiseptic preparations in the ear. A systematic review of the literature was conducted to assess the evidence regarding ototoxicity of surgical antiseptic preparations.

Methods

A literature search was conducted using the PRISMA methods. Key words included “ototoxicity” “hearing loss”, “antiseptic”, “surgical preparation”, “tympanoplasty”, “vestibular dysfunction”, “chlorhexidine”, “iodine”, “povidone”, “ethanol”, and “hydrogen peroxide” using Medline, Embase, Cochrane Library, Scopus and Web of Science. We included peer-reviewed papers that 1) objectively measured ototoxicity in humans or animals through hearing, vestibular function or histologic examination, 2) studied topically applied surgical antiseptic preparations, 3) were either in English or had an English abstract. We excluded papers that were 1) in vitro studies, 2) ear trauma studies, 3) studies of ototoxic ear drops intended for therapy, or 4) case reports. Studies included in the final review were screened using the PRISMA method.

Current systematic review registration number pending: 83,675.

Results

Fifty-six papers were identified as using PRISMA criteria. After applying our exclusion criteria, 13 papers met overall study criteria. Of these, six papers reported ototoxicity of iodine based solutions, five papers reported ototoxicity of chlorhexidine and ethanol and two papers assessed hydrogen peroxide. All papers reviewed were animal studies. Iodine based solutions show least harm overall, while chlorhexidine and high concentrations of alcohol based solutions showed most harm. The evidence on hydrogen based solutions was inconclusive.

Conclusions

The overall evidence for anyone antiseptic solution is weak. There is some evidence that iodine, chlorhexidine, hydrogen peroxide and alcohol based antiseptics have ototoxicity. Conclusive evidence for human ototoxicity from any solution is not strong.

Performance of Bio-Occlusive Dressing as Barrier Protection from Presurgical Chlorhexidine Skin Preparation

Purpose/Aim of the study: Chlorhexdine has been shown to provide excellent and cost-effective presurgical antisepsis. However, standard presurgical concentrations of chlorhexidine (2-4%) are known to cause ocular injury, even in cases in which a bio-occlusive dressing (Tegaderm™) was applied beforehand to the closed eye.

MATERIALS AND METHODS

Three experiments were conducted to assess the barrier performance of Tegaderm™ to chlorhexidine skin prep in vitro and on non-ocular skin. The experiments used water as a control group.

RESULTS

In the first in vitro experiment, the chlorhexidine group showed penetration at the edges of the Tegaderm™ at 5 minutes while the water (control) group never penetrated the Tegaderm™. A subsequent experiment testing the central permeability of the tegaderm showed it to be impermeable to both chlorhexidine and water after 90 minutes. In the in vivo experiment, the chlorhexidine group showed penetration at 10 minutes, while the water (control) group never penetrated the Tegaderm™.

CONCLUSIONS

These data suggest Tegaderm™ is permeable at the edges to chlorhexidine but not water. Based on this, along with reports of ocular injury from chlorhexidine skin preparation of the head despite prior application of Tegaderm™ over the eyes, we advise against using bio-occlusive adhesive dressing to protect the ocular surface from chlorhexidine exposure. We suggest an alternative presurgical antiseptic agent such as povidone-iodine be employed whenever possible.