Remembering the classics: Thoracic epidural anesthesia via the caudal route in infants
Adrian Bosenberg MBChB, DA(SA) FFA(SA)
I am reposting this PAAD previously published on July 15, 2022 to honor and celebrate Adrian Bosenberg’s life time achievement award which will be presented tomorrow at the annual meeting of the Society for Pediatric Anesthesia.
Adrian Bosenberg, to be awarded SPA’s Myron Yaster Lifetime Achievement Award
When the Society for Pediatric Anesthesia was founded in 1986, I/we had 3 main goals:
1. To encourage research, education, and scientific progress in pediatric anesthesia and serve as a forum for discussion
2. To advance the study of pediatric anesthesia and contribute to its growth and influence
3. To develop a community of anesthesiologists who practice pediatric anesthesia
Of the 3 goals, the most important and enduring has been the community and friendships developed of “brothers and sisters from different mothers”. I was blessed and lucky to meet and be befriended by so many, including Dr. Adrian (“Bosie”) Bosenberg. I first met Bosie at one of the first SPA/ASA meetings and was quite literally blown away when he presented his abstract on thoracic epidural anesthesia via the caudal approach in neonates at the ASA meeting. I asked him to re-present this classic paper for the Pediatric Anesthesia Article of the Day and to provide us with the back story of how this study came about.
And this review comes at a perfect time. Bosie will be the recipient of this year’s SPA Myron Yaster lifetime achievement award to be presented at SPA’s annual meeting in New Orleans tomorrow. I am simply over the moon that he has been recognized for his many contributions to our field and will be recognized for this award which he so richly deserves. Please register for the meeting and hoist a cold one when you see him! Myron Yaster MD
Original article
Bösenberg AT, Bland BA, Schulte-Steinberg O, Downing JW. Thoracic epidural anesthesia via caudal route in infants. Anesthesiology. 1988 Aug;69(2):265-9. PMID: 3407976
There was a time not so long ago when the teaching was that children tolerated pain well and did not need perioperative analgesia. The risks of respiratory depression and the potential for addiction with opiate analgesia were reasons given not to treat pain.
In 1983-84 during my pediatric anesthesia fellowship at Seattle Children’s very few children were given intraoperative analgesia except those who were electively ventilated after cardiothoracic surgery.1 Regional anesthesia was discouraged because “it doubled the risk of litigation”. I performed one caudal during my entire fellowship!
In the mid to late 1980’s two events impacted my subsequent practice. Firstly, a study out of Boston Children’s showed that simply providing analgesia (a single dose of fentanyl) improved the outcome of premature infants after PDA ligation.2,3 Secondly, Otto Schulte Steinberg, a German anesthesiologist was completing a sabbatical at my home hospital, the University Kwazulu-Natal in Durban, South Africa.
The Anaesthesia Department at University Kwazulu-Natal provided enormous practical experience. Regional anesthesia formed part of the culture. King Edward VIII Hospital was the tertiary referral hospital for the local population of 12 million. It was essentially an adult hospital and children were treated in separate overcrowded wards. The wards were hopelessly understaffed with inexperienced nurses who rotated through the wards on a regular basis.
The neonatal unit was responsible for between 750 – 1000 high risk deliveries a month and had only eight ventilator beds. Medical and surgical neonates competed for these ventilators. The risks of simply being on a ventilator were high. Comorbidities compounded the problem. Most newborns who required postoperative ventilation simply did not survive.
Single shot caudal blocks were used routinely to provide perioperative analgesia for all procedures below the umbilicus in children. Caudals were used for all neonates and infants undergoing laparotomies. By using caudals the aim was to provide initial postop analgesia and to keep surgical neonates off ventilatory support unless absolutely necessary, and even when necessary, they often died.
Otto Schulte-Steinberg arrived with the idea to thread a caudal catheter into the caudal space-even up to the thoracic level. The research was done in three parts. A piglet and an infant cadaver study showed that this was indeed feasible. On my return from Seattle the clinical study was ready to be done. I jumped at the opportunity because I believed in the potential benefits of epidural analgesia particularly in neonates and infants in our clinical setting. Small epidural needles suitable for use in infants were not available at the time. In fact, very little equipment suitable for regional anesthesia in children was marketed until years later. Most were too expensive for general use. We were forced to improvise.
Infants with biliary atresia were chosen for the clinical part of the study. The abdominal incision was in the thoracic dermatomes and a control Xray taken prior to the cholangiogram could be used for the “epidurogram” to demonstrate the path of the epidural catheter without exposing the infant to additional radiation.
Of the 20 infants included in the initial study the epidural catheter could be thread without resistance to within one vertebral body in 19 infants.4 The one failure met with resistance and did not reach the targeted vertebral body.
With further experience, when this situation arose, the epidural catheter could be freed to pass further by flushing the catheter or gently flexing or extending the infants vertebral column. Tuohy needles, when they became available, tended to cause the catheter to curl in the caudal space unless the orifice was properly aligned with the epidural space. An IV cannula, or Crawford needle placed a few millimeters through the sacrococcygeal membrane has a better success rate in my experience.
Epidural anesthesia reduced the need for post-operative ventilatory support that was common practice when opiate analgesia was used. We initially used intermittent epidural top-ups because continuous infusion pumps were either not available or too expensive. Epidural analgesia had a positive impact on our practice. Compared to opiate analgesia, the morbidity and mortality for esophageal atresia improved. The survival rates to discharge improved from approximately 50% mortality to >90% survival with the same surgical team.
Further perceived benefits included the reduced need for ventilatory support after gastroschisis and omphalocoele closure. The relaxation of the abdominal wall (motor blockade) and the increased tone of the bowel (sympathetic blockade) reduces the gut volume thereby lowering intragastric pressure on closure of the abdominal wall. Sympathetic blockade provided by epidural analgesia also improved gut perfusion in neonates with necrotizing enterocolitis.
Adrian Bosenberg
From Myron
From a historical perspective, the use of epidural catheters thread from the caudal space fundamentally changed our pediatric anesthesia practice forever. Before its introduction, neural blockade was a niche and thought to be unnecessary or even too dangerous except by enthusiasts and pioneers at National Children’s Hospital in DC (Rafaat Hannallah, Linda Joe Rice, Lynn Broadman and others) and in France (Claude Ecoffey, Isabel Murat, Claude Bernard to name a few). The introduction of catheters that could safely be inserted intraoperatively led to the development of what we now call multi-modal analgesia with continuous catheter techniques for intra- and post-operative pain management. Indeed, acute pediatric pain services under the direction of pediatric anesthesiologists can be directly linked to this paper. Pediatric regional anesthesia became as important to our practices as the use of vapor anesthetics and neuromuscular blockade and ultimately led to ultrasound guidance for neural blockade, the Pediatric Regional Anesthesia Network and more. And, in my opinion, it all started with this paper by Bosie.
A final note. When Bosie presented his abstract at the ASA I went up and introduced myself to him during the Q&A session following the presentation. A recurrent problem I had in anesthetizing neonates with esophageal atresia TEF was how to anesthetize them while keeping the infants breathing spontaneously (and thereby avoid gastric distension from positive pressure ventilation). I asked Bosie if he thought this technique would work. He grinned and said “of course” and indeed, it did!
References
1. Yaster M, Flack SH, Martin LD, Morgan PG: An interview with Dr. Anne Marie Lynn, a pioneering woman in medicine. Paediatr Anaesth 2021; 31: 1040-1045
2. Anand KJ, Sippell WG, Aynsley-Green A: Randomised trial of fentanyl anaesthesia in preterm babies undergoing surgery: effects on the stress response. Lancet 1987; 1: 62-6
3. Anand KJ, Hickey PR: Halothane-morphine compared with high-dose sufentanil for anesthesia and postoperative analgesia in neonatal cardiac surgery [see comments]. N.Engl.J.Med. 1992; 326: 1-9
4. Bosenberg AT, Bland BA, Schulte-Steinberg O, Downing JW: Thoracic epidural anesthesia via caudal route in infants. Anesthesiology 1988; 69: 265-269 1988; 69: 265-269