To the Editor—The recent SHEA Expert Guidance articleReference Munoz-Price, Bowdle and Johnston1 addresses the following questions: “Should injection ports used by anesthesia providers in the OR be covered with isopropyl alcohol-containing caps? Should injection ports—without alcohol-containing caps—used by anesthesia providers in the OR be scrubbed with alcohol before each use?” SHEA recommends that intravenous “ports may be disinfected either by scrubbing the port with a sterile alcohol-based disinfectant before each use immediately prior to each use or using sterile isopropyl alcohol containing caps that cover ports continuously … [and that] … Ports should be properly disinfected prior to each individual drug injection…” Yet this will not provide effective disinfection of the internal surface of open-lumen stopcocks.Reference Holroyd2 When the internal surface is contaminated, neither an alcohol pad nor a cap with alcohol-impregnated pads is effective.Reference Holroyd2 Disinfectable, needleless, closed connectors are effectively disinfected with either treatment.Reference Holroyd2 It is very difficult to stop contamination of open-lumen stopcocks,Reference Holroyd2 whereas closed ports can be disinfected.Reference Loftus, Patel and Huysman3 SHEA further recommends that “Stopcocks should have closed injection ports installed to convert them into “closed ports,” or they should be covered with sterile caps.” Unfortunately, this recommendation indicates an infection control equivalence to using either closed injection ports or sterile caps. The recommendation to use a sterile cap does not reduce the infectious risks of open-lumen stopcocks used commonly in anesthesia practices nationwide. Open-lumen stopcocks traditionally use sterile caps, but it is well documented that during use the cap and the stopcock’s internal lumen can become contaminated by bacteria, in up to 32% of cases, and these occurrences are associated with increased patient morbidity and mortality.Reference Loftus, Patel and Huysman3–Reference Loftus, Brindeiro and Kispert5 Even if a new sterile cap is placed on a stopcock after each access (which is not addressed by SHEA), the cap and internal lumen can still become contaminated due to inadvertent contact with a contaminated hand, glove or other surface during cap placement. The risks are clear: “A common route to intravascular device–related bloodstream infections is bacterial contamination of the injection port, which leads to hub colonization, intraluminal migration, and distal seeding of the bloodstream.”Reference Holroyd2 The rate of catheter-related bloodstream infections (CRBSIs) is lower with central venous catheters using disinfectable needle-free connectors than with open-lumen stopcocks (0.7 vs 5.0 per 1,000 catheter days).Reference Yébenes, Vidaur and Serra-Prat6 Mahida et alReference Mahida, Levi, Kearns, Snape and Moppett7 reported that 9% of cases had bacterial contamination in intravenous extension lines connected to open-lumen stopcocks. The 2011 Centers for Disease Control and Prevention (CDC) Guidelines for the Prevention of Intravascular Catheter-Related Infections state the following: “In general, closed catheter access systems are associated with fewer CRBSIs than open systems and should be used preferentially.”8 Whereas SHEAReference Munoz-Price, Bowdle and Johnston1 cites a prospective, randomized studyReference Loftus, Brindeiro and Kispert5 where open-lumen stopcocks disinfected with an alcohol containing scrub device had significantly reduced rates of bacterial contamination compared to standard caps on open stopcocks (32% vs 41%), SHEA emphasizes that “the rate of contamination was high in both groups.” Closed-port access devices (including stopcocks) are widely available. Why does SHEA fail to recommend against the continued use of open-lumen stopcocks in the practice of anesthesia?
The SHEA did not make recommendations for management of anesthesia breathing circuits and reservoir bags after each patient.Reference Munoz-Price, Bowdle and Johnston1 Yet SHEA states that “To reduce the bioburden of organisms and the risk of transmitting these organisms to patients, the facility should clean and disinfect high-touch surfaces on the anesthesia machine and anesthesia work area between OR uses…” and “The potential for clinically significant microbial cross transmission in the intraoperative environment poses a threat to patient safety.”Reference Munoz-Price, Bowdle and Johnston1 A study that simulated operating room anesthetic induction and intubation found that a wide range of surfaces and devices, including the reservoir bag and anesthesia circuit (externally), were contaminated in 100% of scenarios.Reference Birnbach, Rosen, Fitzpatrick, Carling and Munoz-Price9 The CDC recommends cleaning, followed by high-level disinfection or sterilization for the circuit and bag after each patient although disposal of the entire breathing circuit is commonly done in the United States.Reference Hübner, Daeschlein and Lehmann10 Outside the United States, circuits and bags are often reused for multiple patients, replacing only the breathing filter between patients.Reference Hübner, Daeschlein and Lehmann10 Several companies have US Food and Drug Administration (FDA) clearance to market breathing circuits and bags in the United States for multiple patient use by replacing only the breathing filter for each new patient. Numerous studies confirm that heat and moisture microbial filters protect the inside of breathing circuits from microbial contamination but surprisingly most studies did not examine outer surface contamination.Reference Hübner, Daeschlein and Lehmann10 A recent study from Europe and Japan examined the outside surfaces of reservoir bags and circuits and found “high microbial numbers” on the bags and to a lesser extent on the circuits, with an “increasing proportion of pathogenic organisms over time” in spite of disinfectant application to the circuits and bags after each patient.Reference Hübner, Daeschlein and Lehmann10 They cited a risk of contamination of staff and horizontal transmission via hands, with a possible risk for cross-infection.Reference Hübner, Daeschlein and Lehmann10 Although they recommended disinfection of the outer surface of bags and circuits after each patient, their own study showed that the tubing and bags were not reliably disinfected.Reference Hübner, Daeschlein and Lehmann10 This study also excluded certain patients due to “safety concerns” (eg, bloodstream or respiratory infections, immunosuppression, others).Reference Hübner, Daeschlein and Lehmann10 What are the potential risks to subsequent patients from external device microbial contamination, including bloodborne pathogens? How frequently do other anesthesia departments that reuse bags and circuits disinfect them, what disinfection method is used, and what patients, if any, are excluded from having anesthesia with a reused circuit? Clearly, the FDA clearance did not consider external circuit contamination and cross contamination to subsequent patients. Why did SHEA not address this important issue?
