Sterile techniques during pediatric regional anesthesia

Myron Yaster MD and Lynne G. Maxwell MD

“The world is full of obvious things which nobody by any chance ever observes” Sherlock Holmes, Sir Arthur Conan Doyle

It all started with a simple ask.  Several years ago when performing an epidural in Colorado I asked the circulating nurse for DuraPrep (Iodine Povacrylex [0.7% available iodine] and Isopropyl Alcohol, 74%) rather than a chlorhexidine applicator (2% Chlorhexidine Gluconate/70% Isopropyl Alcohol) to prep the skin.  Both the circulating nurse and the pediatric anesthesia fellow were puzzled and asked “why”? I removed the package insert from the chlorhexidine applicator package and showed them that it specifically states “Do not use for lumbar puncture or in contact with meninges”. Indeed, this is why commercial spinal and epidural kits do not include products that contain chlorhexidine and why in my personal practice I used DuraPrep.  Despite this warning in the package insert almost everyone uses it. Indeed, the European Society of Regional Anesthesia and Pain Therapy (ESRA),  the American Society of Regional Anesthesia (ASRA), the American Society of Anesthesiologists (ASA), and the Anesthesia Patient Safety Foundation (APSF) recommend a chlorhexidine skin prep for spinals and epidurals.1-3 There is disconnect.  Is the chlorhexidine contraindication justified?  I must admit that I’ve wondered about this for more than a decade.  I tried to do a randomized clinical trial comparing the 2 solutions and then look for the incidence of catheter related infection or colonization but was prevented from doing it by the Hopkins IRB.  Why? Because the chlorhexidine product insert specifically contraindicated its use. The IRB thought it would be unethical to use chlorhexidine in the study and I’m pretty sure this would foil others from doing this study even in 2023.

I also knew that aside from prep solution differences, very different aseptic techniques are used by pediatric anesthesiologists across America when they perform regional anesthesia, some wear sterile gloves and some don’t, some fully drape some don’t, some drape an ultrasound probe and some don’t, and even attire (mask and hats and sterile gowns) differ between individuals and institutions.  This wide variability in practice is really unusual in our profession.  And yet despite these practice differences, the infection rate in pediatric regional anesthesia is very, very low.4, 5  Thus, does any of this matter?  Does anyone else even perceive that these are issues worthy of standardization (think Sherlock Holmes)? 

Dr. Tessa Mandler, a terrific pediatric anesthesiologist in Colorado, was working with 2 medical students (Alexia Gagliardi and Harin Parikh) on myriad research projects and I asked her if she could use her team to survey members of the Pediatric Regional Anesthesia Network (PRAN) to investigate how they handled these issues.  The results of their efforts are today’s PAAD.  Myron Yaster MD

Original article

Tessa N Mandler, Alexia G Gagliardi, Harin B Parikh, Thomas M Austin, Myron Yaster, David M Polaner.  Sterile techniques during regional placement among pediatric anesthesiologists. Paediatr Anaesth. 2022 Nov 28. PMID: 36441008

One of the problems with almost all survey studies is the low rate of recipient responses.  Mandler et al. decided to survey only institutions within the PRAN network and only the PRAN principal investigator at each study site.  This assured a 100% response rate and eliminated duplicate responses.

What did they find?  Chlorohexidine was the most commonly used solution to prepare the skin for neuraxial blocks (93%). Gown use was institutionally dependent as was the creation of a sterile field with towels/drapes even when neuraxial catheters were used.  Sterile gowns and sterile fields were rarely used for single injection peripheral nerve or caudal blocks.  Interestingly, ultrasound probes were not universally prepared in an aseptic fashion and even when covered, different methods were used (sterile cover/sleeve/condom or Tegaderm).

It is almost impossible to study this prospectively because the incidence of infection is so low.  It would literally require thousands and thousands of patients. Furthermore, in reality, if the infection rate is so low what difference does it make and why bother?  On the other hand, should we accept this wide variation in practice, or can/should we use the PRAN network and SPAIN to continuously evaluate our practices and establish best practice protocols? We are not so sure. Should our professional societies address the use of chlorhexidine for neuraxial blocks with the US FDA to drop the label prohibition in its use for lumbar puncture? What do you think and what are your thoughts?  Does anyone, other than Myron use Duraprep? Drop Myron an email and we’ll post in a reader response.

References

1.           Kinirons B, Mimoz O, Lafendi L, Naas T, Meunier J, Nordmann P. Chlorhexidine versus povidone iodine in preventing colonization of continuous epidural catheters in children: a randomized, controlled trial. Anesthesiology. 2/2001 2001;94(2):239-244. Not in File.

2.           Ecoffey C, Bosenberg A, Lonnqvist PA, Suresh S, Delbos A, Ivani G. Practice advisory on the prevention and management of complications of pediatric regional anesthesia. Journal of clinical anesthesia. Aug 2022;79:110725. doi:10.1016/j.jclinane.2022.110725

3.           Practice Advisory for the Prevention, Diagnosis, and Management of Infectious Complications Associated with Neuraxial Techniques: An Updated Report by the American Society of Anesthesiologists Task Force on Infectious Complications Associated with Neuraxial Techniques and the American Society of Regional Anesthesia and Pain Medicine. Anesthesiology. Apr 2017;126(4):585-601. doi:10.1097/aln.0000000000001521

4.           Walker BJ, Long JB, Sathyamoorthy M, et al. Complications in Pediatric Regional Anesthesia: An Analysis of More than 100,000 Blocks from the Pediatric Regional Anesthesia Network. Anesthesiology. Oct 2018;129(4):721-732. doi:10.1097/aln.0000000000002372

5.           Polaner DM, Taenzer AH, Walker BJ, et al. Pediatric Regional Anesthesia Network (PRAN): a multi-institutional study of the use and incidence of complications of pediatric regional anesthesia. Anesthesia and analgesia. Dec 2012;115(6):1353-64. doi:10.1213/ANE.0b013e31825d9f4b