Two episodes of life-threatening anaphylaxis in the same patient to a chlorhexidine-sulphadiazine-coated central venous catheter

Life-threatening chlorhexidine anaphylaxis caused by skin preparation before chlorhexidine-free central venous catheter insertion: a case report and literature review

Chlorhexidine is a common cause of perioperative anaphylaxis, and global regulatory authorities have issued warnings about anaphylaxis due to chlorhexidine-containing central venous catheters (CVC) and its mucosal absorption. We present a case of life-threatening anaphylaxis after CVC insertion caused by chlorhexidine used for skin preparation. The onset of anaphylaxis was rapid and very severe, resulting in pulseless electrical activity. The patient was successfully resuscitated by emergency veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Our case suggests that even skin preparation before chlorhexidine-free CVC insertion can cause life-threatening anaphylaxis. We reviewed the literature on chlorhexidine anaphylaxis cases and categorized all potential routes of chlorhexidine exposure to assess the risk following skin preparation. Our results showed that skin preparation before CVC insertion was the third most common cause of chlorhexidine anaphylaxis after transurethral exposure and chlorhexidine-containing CVCs. However, skin preparation with chlorhexidine before CVC insertion was sometimes overlooked as a cause of chlorhexidine anaphylaxis, and its risk might be underestimated. Further, no previous reports have described life-threatening anaphylaxis solely due to chlorhexidine skin preparation before CVC insertion. CVC insertion might cause the chlorhexidine used for skin preparation to reach the vascular system and should be recognized as a potential cause of life-threatening chlorhexidine anaphylaxis.

[Update of the recommendations of the Bacteraemia Zero Project]

El proyecto Bacteriemia Zero (BZ) fue el primero de los Proyectos Zero que se implementó en las Unidades de Cuidados Intensivos (UCI), consiguiendo una disminución de las tasas de infección relacionadas con catéter por debajo de las recomendadas por los estándares de calidad de las sociedades científicas. A raíz de la pandemia causada por el SARS-CoV-2 en las UCI, se ha observado un incremento importante de estas tasas de infección. El incremento de las tasas de infección y la necesidad de incorporar en la práctica clínica la mejor evidencia disponible, justifica la necesidad de actualizar las recomendaciones del proyecto BZ. Se constituyó un grupo de trabajo formado por miembros de las diferentes sociedades científicas que consideró que el paquete de medidas obligatorias del proyecto no debía modificarse debido a su eficacia demostrada y decidió incorporar, después de su revisión, las siguientes medidas opcionales: uso de catéteres impregnados con antimicrobianos, uso de apósitos impregnados con clorhexidina, uso de tapones con solución antiséptica en los conectores e higiene corporal diaria con clorhexidina.

Blood compatibility of widely used central venous catheters; an experimental study

An inserted central venous catheter (CVC) is considered foreign material by the inert host defence systems and induce inflammation and thrombus formation. The objective of this study was to evaluate blood compatibility of six commonly used CVCs. Three coated and three uncoated CVC materials were tested in a modified Chandler loop model. Each catheter material circulated in blood from ten different healthy volunteers for 1 h. Blood cell counts and measurements of the inert host defence systems were performed on blood samples from the loop. All the tested catheters demonstrated impact on blood cells, contact coagulation, the complement system, or inflammatory markers, although the impact varied significantly. Of the catheters we evaluated, the most unfavourable blood compatibility profile was found for the polyurethane CVC coated with chlorohexidine and silver sulfadiazine. The greatest variation in blood compatibility between test runs was noted for the silicone dialysis catheter. Poor blood compatibility should be taken seriously but given the experimental design of the current study the clinical significance remains to be evaluated.

The risk of fatal bleeding complications in jugular catheterization in patients with coagulopathy: A retrospective analysis of death cases in closed claims and the Medical Accident Investigating System in Japan

Background

To prevent recurrence of medical accidents, the Medical Accident Investigating System was implemented in October 2015 by the Japan Medical Safety Research Organization (Medsafe Japan) to target deaths from medical care that were unforeseen by the administrator. Medsafe Japan analyzed the 10 cases of central venous catheterization-related deaths reported in the system and published recommendations in March 2017. However, the particular emphasis for the prevention of central venous catheterization-related deaths is unclear.

Methods

This study aimed to identify the recommendation points that should be emphasized to prevent recurrence of central venous catheterization-related deaths. We assessed central venous catheterization in 8530 closed-claim cases between January 2002 and December 2016 covered by the medical insurer Sompo-Japan. Moreover, we compared central venous catheterization-related death in closed-claim cases with death in reported cases.

Results

The background, error type, anatomic insertion site, and fatal complication data were evaluated for 37 closed-claim cases, of which 12 (32.4%) were death cases. Of the 12 closed-claim cases and 10 reported cases, 9 (75.0%) closed-claim cases and 9 (90.0%) reported cases were related to vascular access. Among these, 5 closed-claim cases (41.7%) and 7 reported cases (77.8%) were related to internal jugular vein catheterization (p = 0.28). Coagulopathy was observed in 3 (60.0%) of 5 closed-claim cases and 6 (85.7%) of 7 reported cases.

Conclusions

The risk of internal jugular catheterization in patients with coagulopathy must be carefully considered.

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.

Antiseptic mouthwash, the nitrate-nitrite-nitric oxide pathway, and hospital mortality: a hypothesis generating review

Meta-analyses and several large cohort studies have demonstrated that antiseptic mouthwashes are associated with mortality in hospitalized patients. A clear pathogenic mechanism is lacking, leading to controversy and a reluctance to abandon or limit the use of antiseptic mouthwashes. Here, we generate the hypothesis that a disturbance in nitric oxide homeostasis by antiseptic mouthwashes may be responsible for the observed increase in mortality risk. Nitric oxide is essential in multiple physiological processes, and a reduction in nitric oxide bioavailability is associated with the occurrence or worsening of pathologies, such as atherosclerosis, diabetes, and sepsis. Oral facultative anaerobic bacteria are essential for the enterosalivary nitrate–nitrite–nitric oxide pathway due to their capacity to reduce nitrate to nitrite. Nitrate originates from dietary sources or from the active uptake by salivary glands of circulating nitrate, which is then excreted in the saliva. Because antiseptic mouthwashes eradicate the oral bacterial flora, this nitric oxide-generating pathway is abolished, which may result in nitric oxide-deficient conditions potentially leading to life-threatening complications such as ischaemic heart events or sepsis.

Practice Guidelines for Central Venous Access 2020

These practice guidelines update the Practice Guidelines for Central Venous Access: A Report by the American Society of Anesthesiologists Task Force on Central Venous Access, adopted by the American Society of Anesthesiologists in 2011 and published in 2012. These updated guidelines are intended for use by anesthesiologists and individuals under the supervision of an anesthesiologist and may also serve as a resource for other physicians, nurses, or healthcare providers who manage patients with central venous catheters.

Supplemental Digital Content is available in the text.

Practical guide for safe central venous catheterization and management 2017

Central venous catheterization is a basic skill applicable in various medical fields. However, because it may occasionally cause lethal complications, we developed this practical guide that will help a novice operator successfully perform central venous catheterization using ultrasound guidance. The focus of this practical guide is patient safety. It details the fundamental knowledge and techniques that are indispensable for performing ultrasound-guided internal jugular vein catheterization (other choices of indwelling catheters, subclavian, axillary, and femoral venous catheter, or peripherally inserted central venous catheter are also described in alternatives).

Chlorhexidine allergy in the perioperative setting: a narrative review

Chlorhexidine is an antiseptic with a broad spectrum of activity and a persistent effect on skin. Consequently, it has become an ubiquitous antiseptic in healthcare and the community. As use has become widespread, increasing numbers of cases of allergy have been reported in the literature, including cases of anaphylaxis to chlorhexidine gels used on mucous membranes, chlorhexidine-impregnated devices such as central venous catheters, chlorhexidine preparations used on wounds and broken skin, and cases after dental procedures. Numerous governmental warnings have been issued over recent decades to warn of the risk of allergy to chlorhexidine on mucosal surfaces or in medical devices. Whilst the number of published cases likely underestimates the true prevalence of reactions, we retrospectively surveyed clinics with experience in investigating perioperative chlorhexidine allergy. Despite differences in investigation practice before the survey took place, 13 clinics responded which together had diagnosed 252 cases of anaphylaxis to chlorhexidine, and cases of delayed allergy. In eight of 13 clinics, chlorhexidine was within the top four most commonly diagnosed causes of perioperative anaphylaxis. Despite this, the incidence of anaphylaxis to chlorhexidine is low given that patients are very commonly exposed. Sensitisation of healthcare workers can occur, but is uncommon. Before exposing patients to this antiseptic, consideration of the potential risk vs benefit should be undertaken, particularly for higher risk exposures, such as mucosal exposure or i.v. exposure via impregnated lines. Difficulties exist in protecting patients with known allergies from re-exposure to chlorhexidine, which would be improved with uniform labelling and chlorhexidine product registers.

Chlorhexidine Allergy: On the Rise and Often Overlooked

PURPOSE OF REVIEW

In recent years, the risk of allergy to chlorhexidine is increasingly recognised. In this review, we discuss why the allergy is so easily overlooked and point out several preventative initiatives that can minimise the risk of both chlorhexidine sensitisation and allergy development and accidental re-exposure in patients with chlorhexidine allergy. Testing for chlorhexidine allergy is also discussed.

RECENT FINDINGS

Numerous reports have been published from many different specialties. Symptoms range from mild skin symptoms to life-threatening anaphylaxis. Testing for chlorhexidine allergy is based on skin testing and in vitro testing. Recently, it was found that both skin prick testing and specific IgE have high sensitivities and specificities. This review gives an overview of chlorhexidine allergy with a special focus on preventative initiatives and testing.

Chlorhexidine Allergy: Mild Allergic Reactions Can Precede Anaphylaxis in the Healthcare Setting

Chlorhexidine can cause severe immediate-type allergic reactions such as urticaria, anaphylactic shock or, even, cardiac arrest. We report the case of a patient who developed perioperative anaphylactic shock caused by chlorhexidine 1 year after a postoperative urticarial reaction, which was assumed not to be significant at the time. This case highlights the importance of identifying mild allergy symptoms after exposure to chlorhexidine at the pre-anaesthetic assessment to prevent more severe allergic reactions in future.

Chlorhexidine wipes: Time to stop and think about allergy

Summary

We report three precautionary cases of perioperative anaphylaxis to chlorhexidine isopropyl alcohol antiseptic wipes (CAW). In two cases, the patients were inadvertently re-exposed to CAW despite known chlorhexidine hypersensitivity. Chlorhexidine has been described as ‘the hidden allergen’. As a result, patients may suffer multiple reactions before chlorhexidine is confirmed as the cause. Healthcare workers may not recognize that products they use for common clinical steps contain chlorhexidine. These cases highlight the need for constant vigilance to facilitate the safe management of patients with a history of chlorhexidine anaphylaxis.

An Unexpected Cause of an Acute Hypersensitivity Reaction during Recovery from Anaesthesia

Acute hypersensitivity reactions to chlorhexidine in the operating room are probably more likely to occur during the early phases of anaesthesia because chlorhexidine is often used for cleaning the surgical field or during placement of indwelling catheters. We report a case of an acute hypersensitivity reaction that occurred in the post anaesthetic care unit. Subsequent skin testing suggested sensitivity to chlorhexidine, which had been applied over the vaginal mucosa at the end of surgery. Relevant issues in the investigation of acute hypersensitivity reactions in the post anaesthetic period are discussed.

Effects of chlorhexidine gluconate oral care on hospital mortality: a hospital-wide, observational cohort study

Purpose

Chlorhexidine oral care is widely used in critically and non-critically ill hospitalized patients to maintain oral health. We investigated the effect of chlorhexidine oral care on mortality in a general hospitalized population.

Methods

In this single-center, retrospective, hospital-wide, observational cohort study we included adult hospitalized patients (2012–2014). Mortality associated with chlorhexidine oral care was assessed by logistic regression analysis. A threshold cumulative dose of 300 mg served as a dichotomic proxy for chlorhexidine exposure. We adjusted for demographics, diagnostic category, and risk of mortality expressed in four categories (minor, moderate, major, and extreme).

Results

The study cohort included 82,274 patients of which 11,133 (14%) received chlorhexidine oral care. Low-level exposure to chlorhexidine oral care (≤ 300 mg) was associated with increased risk of death [odds ratio (OR) 2.61; 95% confidence interval (CI) 2.32–2.92]. This association was stronger among patients with a lower risk of death: OR 5.50 (95% CI 4.51–6.71) with minor/moderate risk, OR 2.33 (95% CI 1.96–2.78) with a major risk, and a not significant OR 1.13 (95% CI 0.90–1.41) with an extreme risk of mortality. Similar observations were made for high-level exposure (> 300 mg). No harmful effect was observed in ventilated and non-ventilated ICU patients. Increased risk of death was observed in patients who did not receive mechanical ventilation and were not admitted to ICUs. The adjusted number of patients needed to be exposed to result in one additional fatality case was 47.1 (95% CI 45.2–49.1).

Conclusions

These data argue against the indiscriminate widespread use of chlorhexidine oral care in hospitalized patients, in the absence of proven benefit in specific populations.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5171-3) contains supplementary material, which is available to authorized users.

Antimicrobially Impregnated Catheters: An Overview of Randomized Controlled Trials

In order to acquire an overview of the effectiveness of antimicrobially impregnated catheters on the prevention of catheter related bloodstream infections (CRI), we conducted a systematic review concentrating on randomized controlled trials (RCTs). The analysis end point was CRI; therefore, studies focussing only on catheter colonization were excluded. We did not consider abstracts for analysis. We identified 24 RCTs investigating the effectiveness of antimicrobially impregnated catheters. In addition, we discovered five meta-analyses and four studies investigating cost effectiveness. For the majority of antimicrobially impregnated catheter types only a few studies were available, and not enough to draw conclusions. Therefore, despite a relatively large number of RCTs available, the routine use of antimicrobially impregnated catheters as a measure for CRI prevention remains controversial, with a need for more high quality studies.

Anti-Candida activity of antimicrobial impregnated central venous catheters

Background

Whenever the rate of central line-associated bloodstream infections (CLABSIs) remains high even after the implementation of preventive strategies, the use of chlorhexidine/silver sulfadiazine (CSS) or minocycline/rifampin (MR)-impregnated central venous catheters (CVCs) is currently recommended. Nevertheless, the efficacy of such CVCs against Candida albicans and other emerging non-albicans spp. has been insufficiently studied. This study aims to compare the activity of CSS and MR-impregnated CVCs against the yeasts most frequently isolated from CLABSIs.

Methods

For biofilm formation assays, type strains and clinical isolates of C. albicans, C. glabrata and C. parapsilosis sensu stricto were used. Segments of standard polyurethane, MR and second-generation CSS-CVCs were tested. The biofilm metabolic activity was measured by a semi-quantitative XTT reduction assay.

Results

CSS catheter segments significantly reduced the biofilm metabolic activity by all tested Candida spp., with inhibition ranging from 60% to 100%. The MR catheter segments promoted C. albicans and C. parapsilosis biofilm formation and exhibited an inconspicuous effect against C. glabrata.

Conclusions

Among the recommended antimicrobial CVCs, CSS-CVCs proved to be superior in the inhibition of biofilm formation by the most frequent yeasts causing CLABSIs. Data from this in vitro study may suggest that patients at high risk for invasive candidosis could benefit from the use of CSS-CVCs.

The effects of essential oil, povidone-iodine, and chlorhexidine mouthwash on salivary nitrate/nitrite and nitrate-reducing bacteria

Dietary nitrate is reduced to nitrite and nitric oxide by microbial flora, and this activity is beneficial to vascular health. It has been reported that this bacterial process is inhibited by chlorhexidine mouthwash, although the effects of other products are largely unknown. This study examined the effects of several treatments on salivary nitrate/nitrite and nitrate-reducing bacteria. Twelve university staff and students performed mouth-washing with water (control), essential oil, 0.35% povidone-iodine, or 0.0025% chlorhexidine and then ate 100 g lettuce (110 mg nitrate content), followed by collection of saliva and tongue bacteria at the baseline, and 1, 5, and 10 h thereafter. The individual treatments were separated by an interval of one week. Salivary nitrate/nitrite was measured by the calorimetric method, and a representative nitrate-reducing bacterial species, Veillonella dispar, was detected and semi-quantified using a polymerase chain reaction (PCR) assay. Significant increases in salivary nitrate/nitrite were observed for all treatments (all P < 0.05). The PCR assay showed that water, essential oil, and povidone-iodine mouthwash had little effect, whereas V. dispar DNA bands were markedly inhibited after washing with chlorhexidine. These results suggest that essential oil and povidone-iodine mouthwash have little effect on oral nitrate-reducing activity. Salivary nitrite production was not reduced by chlorhexidine, but the fainter band of V. dispar DNA suggests that longer daily use might blunt this nitrate-reducing activity.

Life-threatening Chlorhexidine Anaphylaxis: A Case Report

Chlorhexidine is a common antiseptic and disinfectant used in the medical field. Allergy to chlorhexidine has been reported in the literature but life-threatening anaphylactic shock is rare. We present a case of severe anaphylactic shock due to chlorhexidine occurring during surgery. Literatures suggest that profound anaphylactic shock to chlorhexidine is commonly preceded by milder, non-specific reactions. These mild symptoms are often dismissed by both the patient and physicians alike. Direct questioning of these symptoms is necessary as a part of the pre-operative assessment and the patient should be referred for further immunology testing if indicated.

Chlorhexidine-silver sulfadiazine-impregnated venous catheters are efficient even at subclavian sites without tracheostomy

BACKGROUND

Chlorhexidine-silver sulfadiazine (CHSS)-impregnated catheters have been found to decrease the risk of catheter-related bloodstream infection (CRBSI) and central venous catheter (CVC)-related costs. However, there are no published data about cost-effectiveness of the use of CHSS-impregnated catheters in subclavian venous access without the presence of tracheostomy (thus, with a very low risk of CRBSI). That was the objective of this study.

METHODS

This was a retrospective study of patients admitted to a mixed intensive care unit who underwent placement of subclavian venous catheters without the presence of tracheostomy.

RESULTS

Patients with standard catheters (n = 747) showed a higher CRBSI incidence density (0.95 vs 0/1,000 catheter-days; P = .02) and higher CVC-related cost per day ($3.78 ± $7.43 vs $3.31 ± $2.72; P < .001) than patients with a CHSS-impregnated catheter (n = 879). Exact logistic regression analysis showed that catheter duration (P = .02) and the type of catheter used (P = .01) were associated with the risk of CRBSI. Kaplan-Meier method showed that CHSS-impregnated catheters were associated with more prolonged CRBSI-free time than standard catheters (log-rank = 9.76; P = .002). Poisson regression analysis showed that CHSS-impregnated catheters were associated with a lower central venous catheter-related cost per day than standard catheters (odds ratio, 0.87; 95% confidence interval, 0.001-0.903; P < .001).

CONCLUSIONS

The use of CHSS-impregnated catheters is an effective and efficient measure for the prevention of CRBSI even at subclavian venous access sites without the presence of tracheostomy.

Allergy to Chlorhexidine

Chlorhexidine is an effective antiseptic which is widely used in dentistry. Over recent years, it has also been used in other healthcare products as well as in cosmetics. Anaphylaxis to chlorhexidine has been increasingly reported throughout the world, including two incidents in the UK where chlorhexidine-containing mouthwash had been used to wash tooth sockets following recent tooth extraction. Chlorhexidine is under-recognized as a cause of anaphylaxis and dentists should be aware of its potential for serious adverse effects. Dentists need to consider whether the washing out of a tooth socket with chlorhexidine solution should be avoided in the treatment of established dry socket. On current evidence the potential risks of using chlorhexidine as irrigation solution for treating an established dry socket appears to outweigh any known benefit. CPD/Clinical Relevance: Chlorhexidine has the potential to cause anaphylaxis in the dental surgery.

Dynamics of plasma levels of specific IgE in chlorhexidine allergic patients with and without accidental re-exposure

BACKGROUND

Chlorhexidine is an effective disinfectant, which may cause severe allergic reactions. Plasma level of specific IgE to chlorhexidine (ImmunoCAP(®) ) has high estimated sensitivity and specificity when measured within 6 months of allergic reaction, but knowledge of the dynamics over longer time periods is lacking and it is unknown whether levels fall below <0.35 kUA/L in patients with previously elevated levels. It is also unclear whether re-exposure influences levels of specific IgE.

OBJECTIVE

To investigate the dynamics of specific IgE in chlorhexidine allergic patients with and without re-exposure.

METHODS

All patients diagnosed with chlorhexidine allergy in the Danish Anaesthesia Allergy Centre January 1999 to March 2015 were invited to participate. The study included blood samples from the time of reaction and time of investigation and blood samples drawn prospectively over several years.

RESULTS

Overall, 23 patients were included. Specific IgE within hours of reaction was available in eight patients and was >0.35 kUA/L in six of these. During allergy investigations, usually 2-4 months later, specific IgE was >0.35 kUA/L in 22 of 23 patients. In the following months/years specific IgE declined <0.35 kUA/L in 17 of 23 patients (most rapidly within 4 months). Nine re-exposures in the healthcare setting were reported by seven patients (35%). Most re-exposures caused symptoms and were followed by an increase in specific IgE. Two patients with specific IgE <0.35 kUA/L reacted upon re-exposure.

CONCLUSIONS & CLINICAL RELEVANCE

Time from reaction should be considered when interpreting specific IgE results. Specific IgE is >0.35 kUA/L in most patients at time of reaction but should be repeated after a few weeks/months if negative. The optimal sampling time seems to be >1 month and <4 months. A value <0.35 kUA/L neither excludes allergy nor implies loss of reactivity in previously sensitized patients. Re-exposures are common, often iatrogenic, and can cause a rebound in specific IgE.

Chlorhexidine-silver sulfadiazine- or rifampicin-miconazole-impregnated venous catheters decrease the risk of catheter-related bloodstream infection similarly

BACKGROUND

The objective of this study was to compare the incidence of catheter-related bloodstream infection (CRBSI) with the use of second-generation chlorhexidine-silver sulfadiazine (CHSS)-impregnated catheters, rifampicin-miconazole (RM)-impregnated catheters, and standard catheters.

METHODS

Retrospective study of patients admitted to an intensive care unit who received CHSS, RM, or standard catheters in femoral venous access.

RESULTS

We diagnosed 18 CRBSIs in 245 patients with standard catheters in 2,061 days, zero CRBSI in 169 patients with CHSS-impregnated catheters in 1,489 days, and zero CRBSI in 227 patients with RM-impregnated catheters in 2,009 days. Patients with standard catheters compared with CHSS- and RM-impregnated catheters showed a higher rate of CRBSI (7.3%, 0%, and 0%, respectively; P < .001) and higher incidence density of CRBSI (8.7, 0, and 0 per 1,000 catheter days, respectively; P < .001). We found in the exact Poisson regression that standard catheters were associated with a higher CRBSI incidence than CHSS-impregnated catheters (P < .001) and RM-impregnated catheters (P < .001), controlling for catheter duration. We found in survival analysis that standard catheters were associated with a lower CRBSI-free time than CHSS-impregnated catheters (P < .001) and RM-impregnated catheters (P < .001).

CONCLUSION

We found that CHSS- and RM-impregnated catheters decreased similarly the risk of CRBSI.

Chlorhexidine-induced anaphylaxis in surgical patients: a review of the literature

BACKGROUND

Chlorhexidine (CHL) has antiseptic and disinfectant properties used to prevent hospital-acquired infections. CHL-induced anaphylaxis is poorly reported in surgical literature despite government warnings and growing recognition. The aim of this review is to increase awareness of CHL-induced anaphylaxis in the surgical population.

METHODS

Literature review of Embase, Medline, PubMed and the Cochrane library using 'anaphylaxis (and) chlorhexidine' search terms.

RESULTS

Thirty-six articles were published on surgical patients suffering anaphylaxis to CHL. Within these, seven patients had two proven separate anaphylactic reactions and one had three separate proven anaphylactic reactions. The most commonly affected speciality was urology. The majority occurred during elective procedures. A history of atopy was surprisingly uncommon as was bronchospasm. Six patients required active chest compressions and 39.71% of patients had their surgical procedure abandoned. Unplanned intensive care admissions occurred in 27.94%.

DISCUSSION

In order to reduce abandoned procedures, unplanned intensive care unit admissions, morbidity and mortality associated with CHL-induced anaphylaxis we recommend the following: rationalization of CHL-containing products, greater vigilance regarding subtle symptoms of CHL allergy, appropriate investigation of these symptoms and a greater awareness of CHL-containing products. Lastly, we outline the appropriate investigations and highlight the need for meticulous documentation in those who are CHL allergic.

Efficiency of chlorhexidine-silver sulfadiazine-impregnated venous catheters at subclavian sites

BACKGROUND

Cost-effectiveness analyses show that chlorhexidine-silver sulfadiazine (CHSS)-impregnated catheters reduce catheter-related bloodstream infection (CRBSI) and central venous catheter (CVC)-related costs. However, no studies have reported the efficiency of CHSS-impregnated catheters for venous access when the risk of CRBSI is low; for example, at the subclavian site. This study determined the cost of a CVC, diagnosis of CRBSI, and antimicrobial agents to treat CRBSI; we did not consider the cost of increased hospital stay.

METHODS

This retrospective study included patients admitted to the intensive care unit at Hospital Universitario de Canarias (Tenerife, Spain) who had a subclavian venous catheter.

RESULTS

Patients with CHSS catheters (n = 353) had a lower incidence density of CRBSI (2.12 vs 0 out of 1,000 catheter-days; P = .02) and lower CVC-related cost per catheter-day (3.35 ± 3.75 vs 3.94 ± 9.95; P = .002) than those with standard catheters (n = 518). CHSS-impregnated catheters were associated with a lower risk of CRBSI (exact logistic regression) (odds ratio, 0.10; 95% confidence interval, -∞ to 0.667; P = .008) than standard catheters when controlling for catheter duration. CHSS-impregnated catheters were also associated with a lower CVC-related cost per catheter day than standard catheters (Poisson regression) (odds ratio, 0.85; 95% confidence interval, 0.001-0.873; P < .001).

CONCLUSIONS

CHSS-impregnated catheters may be efficient in preventing CRBSI in patients with subclavian venous access.

Adenoid cystic carcinoma: A review of recent advances, molecular targets, and clinical trials

Background

Adenoid cystic carcinoma (ACC) is a rare tumor of secretory glands. In this study, recent advances in molecular characterization and in therapeutics are reviewed.

Methods

A search of articles in PubMed and of abstracts from national meetings was performed regarding ACC.

Results

Recent genetic analyses found that recurrent chromosome 6:9 translocations in ACC generate an MYB:NFIB gene fusion resulting in overexpression of the MYB oncoprotein. Several other frequent mutations are recently published that may be relevant for drug development. Several trials of targeted drugs are reviewed. Some agents delay tumor progression, but tumor responses remain rare.

Conclusion

ACCs have a characteristic chromosomal translocation, but also frequently pick up additional mutations. Clinical research is limited by the rarity and slow growth of ACC. Several ongoing trials are testing agents that inhibit fibroblast growth factor receptor signaling or other signaling pathways. Novel treatments based on the recently sequenced tumor genome are under development. © 2015 The Authors Head & Neck Published by Wiley Periodicals, Inc. 38: 620–627, 2016

Chlorhexidine: an unrecognised cause of anaphylaxis

Chlorhexidine is a highly effective antiseptic and disinfectant. In the past 20 years there has been a substantial increase in the number of chlorhexidine containing products used in healthcare. Anaphylaxis to chlorhexidine was first reported in 1984 and was almost always seen in men. However, in the last 4 years we have observed a surge in confirmed cases of anaphylaxis to chlorhexidine, with increasing numbers of female patients recently diagnosed. Yet, awareness of chlorhexidine as a cause of anaphylaxis is low because it is not a drug but a 'hidden' allergen, for example as a coating on medical devices such as central lines and urinary catheters. Patients will often have more than one allergic/anaphylactic reaction before the diagnosis is suspected. We have observed that there is poor recognition of an initial allergic reaction to chlorhexidine, which is well described. This, alongside poor labelling of chlorhexidine containing products, has resulted in further inadvertent exposure resulting in severe anaphylaxis. Prompt referral to a specialist allergy centre ensures appropriate investigations, diagnosis and management. Increasing awareness of the potential risk of life-threatening anaphylaxis associated with chlorhexidine use is vital, particularly in perioperative procedures. Healthcare workers are fundamental in avoiding and preventing further reactions to chlorhexidine containing products in patients diagnosed with anaphylaxis to chlorhexidine.

Standardized testing with chlorhexidine in perioperative allergy--a large single-centre evaluation

BACKGROUND

Perioperative allergic reactions to chlorhexidine are often severe and easily overlooked. Although rare, the prevalence remains unknown. Correct diagnosis is crucial, but no validated provocation model exists, and other diagnostic tests have never been evaluated. The aims were to estimate (i) the prevalence of chlorhexidine allergy in perioperative allergy and (ii) the specificity and sensitivity for diagnostic tests for chlorhexidine allergy.

METHODS

We included all patients investigated for suspected perioperative allergic reactions in the Danish Anaesthesia Allergy Centre during 2004-2012. The following tests were performed: specific IgE (Immunocap® ; Phadia AB, Sweden), histamine release test (HR) (RefLab ApS, Denmark), skin prick test (SPT) and intradermal test (IDT). Positivity criteria were as follows: specific IgE >0.35 kUA/l; HR class 1-12; SPT mean wheal diameter ≥3 mm; IDT mean wheal diameter ≥ twice the diameter of negative control. Chlorhexidine allergy was post hoc defined as a relevant clinical reaction to chlorhexidine combined with two or more positive tests. Based on this definition, sensitivity and specificity were estimated for each test.

RESULTS

In total, 22 of 228 patients (9.6%) met the definition of allergy to chlorhexidine. Estimated sensitivity and specificity were as follows: specific IgE (sensitivity 100% and specificity 97%), HR (sensitivity 55% and specificity 99%), SPT (sensitivity 95% and specificity 97%) and IDT (sensitivity 68% and specificity 100%).

CONCLUSIONS

In patients investigated for suspected perioperative allergic reactions, 9.6% were diagnosed with allergy to chlorhexidine. Using our definition of chlorhexidine allergy, the highest combined estimated sensitivity and specificity was found for specific IgE and SPT.

Cost/benefit analysis of chlorhexidine-silver sulfadiazine-impregnated venous catheters for femoral access

Sixty-four patients with chlorhexidine-silver sulfadiazine-impregnated catheters had a lower rate of catheter-related bloodstream infection and lower central venous catheter-related costs per catheter day than 190 patients with a standard catheter.

Prevention of catheter infection using a biodegradable tissue adhesive composed of human serum albumin and disuccinimidyl tartrate

A new material was prepared to reduce catheter infection composed of a flocked silicone sheet (AmTiO2NP-F) with TiO2 nanoparticle–immobilized poly(ethylene terephthalate) fibers modified with surface amino groups. This system was used in conjunction with a tissue adhesive composed of disuccinimidyl tartrate and human serum albumin. At a fixed disuccinimidyl tartrate content of 0.2 mmol in human serum albumin solution, AmTiO2NP-F bonded well with collagen-based casing (a model material for skin), with bond strength increasing to a maximum of 38 w/v% human serum albumin. The adhesive bonded AmTiO2NP-F to subcutaneous tissue in mice, and infiltration of the tissue into the AmTiO2NP-F further increased the bond strength for long-term insertions. The material was degraded within 7 days of implantation, and tissue reaction was mild, while infection was completely prevented. These results indicate that the combined use of AmTiO2NP-F and disuccinimidyl tartrate-A for implanted catheters can significantly alleviate the associated risk of infection.

Chlorhexidine-silver sulfadiazine-impregnated venous catheters save costs

BACKGROUND

Previous cost-effectiveness analyses have found that the use of chlorhexidine-silver sulfadiazine (CHSS)-impregnated catheters is associated with decreased catheter-related bloodstream infections (CRBSI) and central venous catheter (CVC)-related costs. However, in these analyses, the CVC-related cost included the increase of hospital stay.

OBJECTIVE

Our aim was to determine the immediate CVC-related cost (including only the cost of CVC, diagnosis of CRBSI, and antimicrobials for the treatment of CRBSI) of using a CHSS or a standard catheter in internal jugular venous access.

METHODS

We performed a prospective, observational, cohort study of patients admitted to the intensive care unit (ICU), Hospital Universitario de Canarias (Tenerife, Spain), who received 1 or more internal jugular venous catheters.

RESULTS

The study included 245 CHSS-impregnated catheters and 391 standard catheters. Exact logistic regression analysis showed that CHSS-impregnated catheters were associated with a lower incidence of CRBSI, controlling for catheter duration, than standard catheters (0 vs 5.04 CRBSI per 1,000 catheter-days, respectively; odds ratio, 0.80; 95% confidence interval: 0.712-0.898; P < .001). Poisson regression showed that CHSS-impregnated catheters were associated with lower CVC-related cost per day than standard catheters (€3.78 ± €4.45 vs €7.28 ± €16.71, respectively; odds ratio, 0.52; 95% confidence interval: 0.504-0.535; P < .001). Survival analysis showed that CHSS-impregnated catheters were associated with increased CRBSI-free time compared with standard catheters (χ(2) = 14.9; P < .001).

CONCLUSION

The use of CHSS-impregnated catheters reduced the incidence of CRBSI and immediate CVC-related costs in the internal jugular venous access.

Chlorhexidine and hypersensitivity reactions in dentistry

Immunological reactions to chlorhexidine, including allergy (Type I hypersensitivity) and allergic contact dermatitis/stomatitis (Type IV hypersensitivity), have been recognised for many years. This potential safety issue, however, is not well known within dentistry. The purpose of this paper is to alert dentists and dental care professionals to the potential of chlorhexidine in causing hypersensitivity reactions and to consider this possibility if unexplained hypersensitivity reactions occur.

Anaphylaxis to chlorhexidine-coated central venous catheters: a case series and review of the literature

BACKGROUND

Anaphylactic reactions to chlorhexidine are rare but are being reported increasingly in association with a variety of products.

METHODS

We report three cases of anaphylaxis to chlorhexidine in patients presenting for cardiac surgery.

RESULTS

In each case, anaphylaxis was precipitated by the insertion of a central venous catheter impregnated with chlorhexidine acetate. Subsequent investigations confirmed chlorhexidine as the causal agent.

CONCLUSION

Extensive use of chlorhexidine to reduce hospital-acquired infections has the potential to sensitize a small proportion of patients, leading to life-threatening anaphylaxis on subsequent exposure.

Peri-operative anaphylaxis

Peri-operative anaphylaxis is an important cause for mortality and morbidity associated with anaesthesia. The true incidence is unknown and is most likely under reported. Diagnosis can be difficult, particularly as a number of drugs are given simultaneously and any of these agents can potentially cause anaphylaxis. This review covers the clinical features, differential diagnosis and management of anaphylaxis associated with anaesthesia. The investigations to confirm the clinical suspicion of anaphylaxis and further tests to identify the likely drug(s) are examined. Finally the salient features of common and rare causes including non-drug substances are described.

Near fatal intra-operative anaphylaxis to chlorhexidine--is it time to change practice?

The authors report a case of a near fatal anaphylactic reaction to chlorhexidine. Increasingly adverse reactions are being reported with the use of chlorhexidine. Serious reactions are related to use on mucous membranes and acceptable alternatives are readily available. Therefore, the fundamental question that must be asked is: is it time to withdraw chlorhexidine preparations used for mucous membranes?

Chlorhexidine impregnated central venous catheter inducing an anaphylatic shock in the intensive care unit

Chlorhexidine, a bisbiguanide, is widely used as an antiseptic agent in medical practice as it has the greatest residual antimicrobial activity. Central venous catheters coated extraluminally with chlorhexidine have been made to reduce extraluminal contamination. By using both the chlorhexidine-alchohol skin preparation and antimicrobial-coated catheters during vascular cannulation, it can reduce catheter related bloodstream significantly [1]. The reduction in infection rate is especially vital in critically ill patients who require long-term vascular access. Adverse reactions to chlorhexidine are rare and uncommon, and have been under-recognised as a cause of anaphylaxis. There are several reports of allergic reactions following exposure to chlorhexidine. We report of a case of anaphylaxis shock requiring cardiopulmonary resuscitation during the placement of a chlorhexidine impregnated central venous catheters.

Prevention of central venous catheter-related infection: update

Central venous catheters (CVCs) are an essential part of modern-day healthcare, but infections associated with these devices continue to cause significant morbidity and mortality. There are many approaches for the prevention of CVC-related infection and these are outlined in national guidelines. The Department of Health Saving Lives campaign has developed a care-bundle for the prevention of CVC-related infections that focuses on the fundamental actions to be undertaken during the catheter insertion process and ongoing care. If the rate of catheter-related infection remains high despite the implementation of these infection prevention strategies, the use of novel antimicrobial technologies and practices may be considered. These include CVCs that contain antimicrobial agents, such as antiseptics or antibiotics, needleless intravenous (IV) access devices coated with silver and/or chlorhexidine, IV dressings incorporating chlorhexidine, and the use of antimicrobial catheter lock solutions, such as antibiotics, chelators or ethanol. This article outlines the different types of CVCs available, the risk of infection associated with their use and established and novel measures for prevention of these infections.

IgE-mediated chlorhexidine allergy: a new occupational hazard?

BACKGROUND

Chlorhexidine is an effective antimicrobial agent commonly used in UK hospitals, primarily for skin decontamination. Recent UK infection control guidelines recommend the use of 2% chlorhexidine solution in specific clinical settings, thus increasing chlorhexidine use by health care workers (HCWs). Chlorhexidine has been widely reported to cause IgE-mediated allergic reactions (from urticaria and angioedema to anaphylaxis) among patients undergoing surgery/invasive procedures. Despite its widespread use in health care settings, there are no reports of clinically confirmed occupational IgE-mediated chlorhexidine allergy.

AIMS

To identify cases of chlorhexidine allergy among health care workers.

METHODS

A questionnaire was distributed among HCWs in wards and operating theatres at a UK district general hospital to raise awareness of potential chlorhexidine allergy and to invite those with possible clinical allergy to come forward for further testing. Diagnosis was based on an appropriate clinical history with positive serum-specific IgE to chlorhexidine and/or positive skin prick testing.

RESULTS

Four cases of occupational IgE-mediated allergy to chlorhexidine were identified.

CONCLUSIONS

Despite its excellent antimicrobial properties, chlorhexidine is an occupational allergen. We suggest that chlorhexidine allergy be included in the differential diagnosis of HCWs presenting with work-related allergic symptoms. Increased awareness and easier access to chlorhexidine-specific IgE serological testing should facilitate early diagnosis of affected HCWs, allowing appropriate avoidance measures to be instigated--thus reducing the risk of potentially severe allergic reactions in the future.

Chlorhexidine - Pharmacology and Clinical Applications

chlorhexidine is a widely used skin antisepsis preparation and is an ingredient in toothpaste and mouthwash. It is an especially effective antiseptic when combined with alcohol. Its antimicrobial effects persist because it is binds strongly to proteins in the skin and mucosa, making it an effective antiseptic ingredient for handwashing, skin preparation for surgery and the placement of intravascular access. Catheters impregnated with chlorhexidine and antimicrobial agents can reduce the incidence of catheter-related bloodstream infections. Contact dermatitis related to chlorhexidine is not common in health care workers. The incidence of contact dermatitis to chlorhexidine in atopic patients is approximately 2.5 to 5.4%. Acute hypersensitivity reactions to chlorhexidine are often not recognised and therefore may be underreported. This review discusses the pharmacology, microbiology, clinical applications and adverse effects of chlorhexidine.

A case of anaphylaxis to chlorhexidine during digital rectal examination

Chlorhexidine is widely used as an antiseptic and disinfectant in medical and nonmedical environments. Although the sensitization rate seems to be low, its ubiquitous use raises the possibility of sensitization in many patients and medical care workers. We describe a patient with anaphylaxis during digital rectal examination with chlorhexidine jelly. Urticaria, angioedema, dyspnea, and hypotension developed within a few minutes of the rectal examination. The patient fully recovered after treatment with epinephrine and corticosteroids. Skin tests for chlorhexidine were undertaken 5 weeks later, showing positive prick and intradermal skin tests. Within 30 min of the skin test, the patient complained of febrile sensation, chest tightness, angioedema, and urticaria on the face and trunk. An enzyme allergosorbent test for latex was negative. We present this case to alert clinicians about hypersensitivity to chlorhexidine that could potentially be life-threatening. We suggest that chlorhexidine should be recognized as a causative agent of anaphylaxis during procedural interventions.