Cryoablation for Postoperative Pain Control after the Nuss Procedure for Pectus Excavatum
Jonathan Bucan, MD and Nathan M Novotny, MD
Beaumont Health, Royal Oak

A rare few pediatric surgeons have impacted the field to the extent that deserves a paradigm shift and naming of a procedure after the surgeon. Donald Nuss is one of those rare few. Nuss’ development of a minimally invasive approach revolutionized the treatment of pectus excavatum and the procedure was rapidly adopted. One major challenge of the treatment of pectus excavatum however is the postoperative pain. Cryoablation for postoperative pain control after the Nuss procedure is the newest attempt at controlling one of the Nuss procedure’s biggest challenges.

Due to significant post-operative pain following the Nuss Procedure, common methods of pain control include patient-controlled analgesia (PCA) and thoracic epidurals. These methods often include continuous flow of narcotics, weaned over the course of the hospital stay, and transitioned to oral analgesia for home use. However, these types of analgesia do not come without risk. Epidurals can be misplaced and malfunction, while PCAs have conflicting data on whether they adequately control early post-operative pain, and the risk for opioid dependence continues to linger in the background.1 While PCAs have been shown to be beneficial over epidurals, hospital length of stays and pain scores are unacceptably high(Is there a reference for this?). Enter cryoablation. Intraoperative cryoablation of intercostal nerves is the next best thing to happen to pediatric surgery since the development of electrocautery surgery! (Maybe a little over the top, but you get the point) cryoanalgesia helps prevent pain following the Nuss Procedure by freezing affected peripheral nerves and producing pain relief that is long lasting and leads to decreased length of stay.2 According to one study, mean postoperative length of stay was significantly shorter in patients with cryoanalgesia (N = 10) than in a previous cohort treated with thoracic epidural (N = 15), and pain was well controlled.3 Another study which randomized 20 patients to receive either cryoablation (N = 10) or thoracic epidural (n = 10) suggested that median LOS decreased by 2 days in patients undergoing cryoablation, to 3 days from 5 days.4 Finally, one other study took 35 patients treated with cryoablation compared to 32 epidural and 33 PCA patients which resulted in less time to pain control with oral medication (21 h, versus 72 and 67 h, p < 0.01), and decreased LOS (1 day, versus 4.3 and 4.2 days, p < 0.01).5 Pause for a moment. Read that again. Cryoablation patients stayed a single day in the hospital versus 4+ days for our conventional methods of pain control. And yet, there is no free lunch. Astute clinicians will ask, ‘what is it going to cost me?’ Across the three studies mentioned above, mean operating time increased anywhere from 30 minutes –46.5 minutes.3,4,5Also, due to

immediate pain relief following the procedure from cryoablation, patients may ignore activity restrictions and require re-intervention due to a possible displaced Nuss bar.6(wonder if its worth re-wording slightly to make it clear that it’s a suggestion of potential increased bar displacement and that its not been shown …yet .. possibly 😉 )And yet still compelling.The Nuss Procedurewas a revolutionary approach to correct pectus excavatum. But it hurts like a bitch-unsure. Agree with the sentiment, would very much use it myself and possibly worse -( i spent most of yesterday with every sentance including twat) But wonder whether for the sake of a sentance, it’s worth not offending. I dont feel strongly though. Cryoablation of intercostal nerves takes a little time in the operating room but is a potential solution to days and weeks of pain postoperatively for patient and surgeon. Cryoablation provides instantaneous pain relief, decreased length of stay, and better overall pain control than previous conventional methods. Cryoablation may be that revolutionary approach to pain control that Dr. Nuss’s revolutionary procedure needs.References1.Shawn D St Peter, Kathryn A Weesner, Eric E Weissend, et al, “Epidural vs patient-controlled analgesia for postoperative pain after pectus excavatum repair: a prospective, randomized trial”, Journal of Pediatric Surgery. 2012 Jan;47(1):148-53. Doi: 10.1016/j.jpedsurg.2011.10.0402.Sunghoon Kim, Olajire Idowu, Barnard Palmer, Sang H. Lee, “Use of transthoracic cryoanalgesia during the Nuss Procedure”, Journal of Thoracic Cardiovascular Surgery. 2016 Mar;151(3):887-888. Doi: 10.1016/j.jtcvs.2015.09.1103.Claire Graves, Olarjire Idowu, Sang Lee, et al, “Intraoperative cryoanalgesia for managing pain after the Nuss procedure”, Journal of Pediatric Surgery. 2017 Jan;52(6):920-924. Doi: 10.1016/j.jpedsurg.2017.03.0064.Claire E Graves, Jarrett Moyer, Michael J. Zobel, et al, “Intraoperative intercostal nerve cryoablation during the Nuss procedurereduces length of stay and opioid requirement: A randomized clinical trial”, Journal of Pediatric Surgery. 2019;54(11):2250. Doi: 10.1016/j.jpedsurg.2019.02.0575.Dekonenko C, Dorman RM, Duran Y, et al, “Post operative pain control modalities for pectus excavatum repair: A prospective observational study of cryoablation compared to results of a randomized trial of epidural vs patient-controlled analgesia”, Journal of Pediatric Surgery. 2019 Oct 26;S0022-3468 Doi: 10.1016/j.jpedsurg.2019.09.0216.Benjamin Keller, Sandra Kabagambe, James Becker, et al, “Intercostal nerve cryoablation versus thoracic epidural catheters for postoperative analgesia following pectus excavatum repair: Preliminary outcomes in twenty-six cryoablation patients”, Journal of Pediatric Surgery. 2016 Dec;51(12):2033-2038 Doi: 10.1016/j.jpedsurg.2016.09.034

 

Inguinal hernia wayfinding

Skin

Does it really matter? Skin crease, centred over the little blue line (superficial epigastric)

Depth

See Scarpa’s, open Scarpa’s, then look for the fibres of external oblique. Move the retractors up and down to see if there’s one more fine layer to go through. Then…

North/South (Cephalo-caudal)

You have to see the border of external oblique, where it rolls under to form the inguinal ligament. Then…

East/West

(Medial Lateral)

Follow the line of the inguinal ligament. See where the cord exits and the angle changes. Look for the intercrural fibres. If in doubt, in boys pull on the testis and see the cord tighten. Only then can you open the canal or start dissecting the cord.

Inguinal Wayfinding

 

 

 

 

 

 

 

 

 

 

The age-old question: lap versus open fill-in-the-blank. Today, class, we will be answering the question of lap versus open pyloromyotomy. When I trained circa 2012, my attendings were doing about half and half open vs. lap. Since finishing training, I haven’t done a single open pyloromyotomy but there are plenty of surgeons including at least one esteemed editor of this site, who still do (and advocate for) open pyloromyotomy. What factors help a surgeon’s journey in deciding laparoscopic versus open pyloromyotomy for pyloric stenosis? I’m glad you asked.

 

A recent meta-analysis1 concluded that there were no differences between the two approaches in major or minor complications, operative time, and length of stay. The laparoscopic approach was associated with a shorter time to full feeds but, let’s be realistic here, who cares if it doesn’t change length of stay? Any of these studies reviewed by this paper that found a faster time to full feeds found their ‘statistically significant difference’ in hours, not days which, of course, renders this difference clinically insignificant.

 

Interestingly, they cited one paper2 that described improved cosmesis from the laparoscopic incisions versus the open incision. As you might expect, these included the traditional right upper quadrant incision and not the periumbilical incision that many surgeons now employ. 

 

Hypothetically speaking, if I had a 1 month old baby (jeez, this is just hypothetical, right?) with pyloric stenosis, which approach would I prefer? I think the answer is much simpler than you might expect. I would want the approach that my baby’s surgeon preferred. A comfortable, competent surgeon is better than not. This is not a situation where one approach is clearly beneficial over the other. Thankfully, this disease process has wonderful outcomes and these discussions are perfect for dogmatic lunchroom discussions and blogposts but probably don’t make much difference to the baby.

 

 

1Sathya C, Wayne C, Gotsch A, Vincent J, Sullivan KJ, Nasr A. Laparoscopic versus open pyloromyotomy in infants: a systematic review and meta-analysis. Pediatr Surg Int. 2017 Mar;33(3):325-333. doi: 10.1007/s00383-016-4030-y. Epub 2016 Dec 10. PMID: 27942806.

 

2Siddiqui S, Heidel RE, Angel CA, Kennedy AP Jr. Pyloromyotomy: randomized control trial of laparoscopic vs open technique. J Pediatr Surg. 2012 Jan;47(1):93-8. doi: 10.1016/j.jpedsurg.2011.10.026. PMID: 22244399.

 

 

 

 

 

 

 

 

Zachary H. Rollins, BS and Nathan M. Novotny, MD

Beaumont Children’s and Oakland University William Beaumont School of Medicine

In order to maximize the clinical benefit of the Kasai hepatoportoenterostomy in biliary atresia (BA), time is liver. If operated on in the first 60 days of life roughly 70% of infants reestablish bile flow. If operated on even younger, such as at 30 days old, there is significantly increased survival with native liver[i]. HIDA scan is a controversial step in the diagnostic pathway for biliary atresia. To HIDA or not to HIDA in possible biliary atresia – that is the question.

The HIDA scan is often used as a catch-all term for hepatobiliary scintigraphy using derivatives of iminodiacetic acid (IDA). Tests such as PIPIDA, BrIDA, DISIDA, are included when referring to the HIDA scan in this article. In theory, the HIDA scan should make for an ideal screening test for biliary atresia. We are trying to figure out if bile is excreted into the bowel. If so, the baby doesn’t have biliary atresia. A 2013 systematic review and meta-analysis of HIDA for the diagnosis of BA determined that HIDA scan has a cumulative sensitivity of 98.7% (range 98.1-99.2%) and a specificity of 70.4 (range 68.5%-72.2%)[ii]. A subsequent 2015 meta-analysis found the sensitivity to be 93.4% (range 90.3%-95.7%) and specificity to be 69.2% (range 65.1%-73.1%)[iii]. Regardless, the specificity isn’t near good enough to correctly identify biliary atresia, but the sensitivity makes it a reasonable screening test for biliary patency. The question remains how much does this add to the workup of the cholestatic infant? Many of the potential causes of neonatal cholestasis such as Alagille syndrome, idiopathic neonatal hepatitis, and parenteral associated cholestasis commonly have non-excreting scans from secondary hepatic congestion. Put more succinctly, “scintigraphy adds little to the routine evaluation of the cholestatic infant, but may be of value in determining the patency of the biliary tract, thereby excluding BA.”[iv]  To further complicate matters excretion of contrast into the intestines does not always exclude BA. But, why?

When ordering a HIDA scan for BA it is important to remember that the disease course is progressive fibrotic obliteration of the extrahepatic bile ducts. If a HIDA scan is ordered too early in the disease course, results can be misleading. One case series reported 6 patients found to have biliary atresia who had biliary patency on initial HIDA scan. Five of these cases were found to have decreased or delayed excretion[v]. This reflects the early changes in the disease before complete obstruction occurs. This is the same time period for the infant with BA where surgical intervention would be most beneficial. It is our suggestion that if you choose to order a HIDA scan, any abnormality should limit the test’s ability to definitively rule out BA. If instead you decide to obtain a HIDA scan before proceeding to cholangiogram, be wary of a negative HIDA scan and persistent jaundice. In this case have a low threshold for reordering the scan after a few days if the cholestasis has not resolved and you are still not ready to perform the cholangiogram.

Pretreatment with phenobarbital can improve the specificity of the HIDA scan, but is it enough to significantly help? The suggested pretreatment protocol to improve HIDA specificity is phenobarbital at 5mg/kg per day for 3-5 days[vi]. The theory behind this is: pretreating with phenobarbital induces hepatic enzymes further stimulating biliary uptake and excretion. This will not change the outcome of a scan if the extrahepatic bile ducts are obstructed, but will make excretion more likely in cases where there is poor uptake from congestion. In the 2013 meta-analysis pretreatment with phenobarbital was found to increase the specificity of the HIDA scan to 72.2% [69.4%-97.8]. Uh, like a 2% increase? So not only do we not gain enough in specificity to make pretreatment worthwhile, it delays the diagnosis and time to take the patient to the operating room decreasing the success of the Kasai procedure.

There are certain situations where HIDA is even less useful. Beware the HIDA scan in the preemie on parenteral nutrition[vii]. Preemies on TPN are more likely to have TPN associated cholestasis which will also cause diminished tracer excretion. And finally, if the cholestatic infant has persistent acholic stools, a HIDA scan really doesn’t add anything that isn’t already clear from the clinical picture. An important tool for both clinician and parents, we have linked a stool cardwith images of cholic and acholic stools because one person’s clay is not another’s.

The HIDA scan can have value as a screening test, but it is important to realize its limitations in a progressive disease. Waiting 5 days for pretreatment is not recommended, especially when subsequent testing of greater value such as liver biopsy has an associated turnaround time. The one exception is if you are already planning an operation but the delay to operation is several days. Recent case reports have shown that it is safe to skip the HIDA scan entirely and proceed with the more invasive gold standard testing such as the cholangiogram and liver biopsy in the infant with cholestasis. To HIDA or not to HIDA in possible biliary atresia? If it helps you get to more definitive testing or if it helps rule out BA in a patient with low likelihood, go for it. However, chances are you probably don’t need it for the diagnosis of BA.

[i] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3888317/

[ii] https://link.springer.com/article/10.1007/s00247-013-2623-3#Tab2

[iii] https://link.springer.com/article/10.1007%2Fs12519-015-0071-x

[iv] https://journals.lww.com/jpgn/Fulltext/2017/01000/Guideline_for_the_Evaluation_of_Cholestatic.23.aspx

[v] https://www.sciencedirect.com/science/article/pii/S0022347619317342

[vi] https://www.sciencedirect.com/science/article/pii/S0140673609609466?via%3Dihub

[vii] https://pediatrics.aappublications.org/content/142/1_MeetingAbstract/214

Cryoablation for Postoperative Pain Control after the Nuss Procedure for Pectus Excavatum

Jonathan Bucan, MD¹ and Nathan M Novotny, MD¹’²

¹Beaumont Health, Royal Oak, MI, USA

²Monroe Carell, Jr. Children’s Hospital at Vanderbilt, Nashville, TN, USA

A rare few pediatric surgeons have impacted the field to the extent that deserves a paradigm shift and naming of a procedure after the surgeon. Donald Nuss is one of those rare few. Nuss’ development of a minimally invasive approach revolutionized the treatment of pectus excavatum and the procedure was rapidly adopted. Postoperative pain is one major challenge of the treatment of pectus excavatum. Cryoablation for postoperative pain control after the Nuss procedure is the newest attempt at controlling one of the Nuss procedure’s biggest challenges.

Due to significant post-operative pain following the Nuss Procedure, common methods of pain control include patient-controlled analgesia (PCA) and thoracic epidurals. These methods often include continuous flow of narcotics, weaned over the course of the hospital stay, and transitioned to oral analgesia for home use. However, these types of analgesia do not come without risk. Epidurals can be misplaced and malfunction, while PCAs have conflicting data on whether they adequately control early post-operative pain, and the risk for opioid dependence continues to linger in the background. While PCAs have been shown to be beneficial over epidurals, hospital length of stays and pain scores are unacceptably high.1 Enter cryoablation.

Intraoperative cryoablation of intercostal nerves is the next best thing to happen to pediatric surgery since the development of electrocautery surgery! Okay, maybe that is a little over the top, but you get the point. Cryoanalgesia helps prevent pain following the Nuss Procedure by freezing affected peripheral nerves and producing pain relief that is long lasting and leads to decreased length of stay.2 According to one study, mean postoperative length of stay was significantly shorter in patients with cryoanalgesia (N = 10) than in a previous cohort treated with thoracic epidural (N = 15), and pain was well controlled.3 Another study which randomized 20 patients to receive either cryoablation (N = 10) or thoracic epidural (n = 10) suggested that median LOS decreased by 2 days in patients undergoing cryoablation, to 3 days from 5 days.4 Finally, one other study took 35 patients treated with cryoablation compared to 32 epidural and 33 PCA patients which resulted in less time to pain control with oral medication (21 h, versus 72 and 67 h, p < 0.01), and decreased LOS (1 day, versus 4.3 and 4.2 days, p < 0.01).5  Pause for a moment. Read that again. Cryoablation patients stayed a single day in the hospital versus 4+ days for our conventional methods of pain control. And yet, there is no free lunch. Astute clinicians will ask, ‘what is it going to cost me?’ Across the three studies mentioned above, mean operating time increased anywhere from 30 minutes – 46.5 minutes.3,4,5 Also, due to immediate pain relief following the procedure from cryoablation, it is conceivable that patients may ignore activity restrictions and unknowingly displace the bar.6 And yet cryoablation is still compelling.

The Nuss Procedure was a revolutionary approach to correct pectus excavatum. But it hurts like crazy. Cryoablation of intercostal nerves takes a little time in the operating room but is a potential solution to days and weeks of pain postoperatively for patient and surgeon. Cryoablation provides instantaneous pain relief, decreased length of stay, and better overall pain control than previous conventional methods.

Cryoablation may be that revolutionary approach to pain control that Dr. Nuss’s revolutionary procedure needs.

 

References

  1. Shawn D St Peter, Kathryn A Weesner, Eric E Weissend, et al, “Epidural vs patient-controlled analgesia for postoperative pain after pectus excavatum repair: a prospective, randomized trial”, Journal of Pediatric Surgery. 2012 Jan;47(1):148-53. Doi: 10.1016/j.jpedsurg.2011.10.040
  2. Sunghoon Kim, Olajire Idowu, Barnard Palmer, Sang H. Lee, “Use of transthoracic cryoanalgesia during the Nuss Procedure”, Journal of Thoracic Cardiovascular Surgery. 2016 Mar;151(3):887-888.Doi: 10.1016/j.jtcvs.2015.09.110
  3. Claire Graves, Olarjire Idowu, Sang Lee, et al, “Intraoperative cryoanalgesia for managing pain after the Nuss procedure”, Journal of Pediatric Surgery. 2017 Jan;52(6):920-924.  Doi: 10.1016/j.jpedsurg.2017.03.006
  4. Claire E Graves, Jarrett Moyer, Michael J. Zobel, et al, “Intraoperative intercostal nerve cryoablation during the Nuss procedure reduces length of stay and opioid requirement: A randomized clinical trial”, Journal of Pediatric Surgery. 2019;54(11):2250.Doi: 10.1016/j.jpedsurg.2019.02.057
  5. Dekonenko C, Dorman RM, Duran Y, et al, “Post operative pain control modalities for pectus excavatum repair: A prospective observational study of cryoablation compared to results of a randomized trial of epidural vs patient-controlled analgesia”, Journal of Pediatric Surgery. 2019 Oct 26;S0022-3468Doi: 10.1016/j.jpedsurg.2019.09.021
  6. Benjamin Keller, Sandra Kabagambe, James Becker, et al, “Intercostal nerve cryoablation versus thoracic epidural catheters for postoperative analgesia following pectus excavatum repair: Preliminary outcomes in twenty-six cryoablation patients”, Journal of Pediatric Surgery. 2016 Dec;51(12):2033-2038                                                                                                                                                                          Doi: 10.1016/j.jpedsurg.2016.09.034

Not All Free Air in the NICU is Necrotizing Enterocolitis 

Paul Holtrop MD1, Paras Khandhar MD1, and Nathan Novotny MD1, 2

1Beaumont Children’s, Royal Oak, MI, USA

2Monroe Carell, Jr. Children’s Hospital at Vanderbilt, Nashville, TN, USA

When a tiny preterm baby in our neonatal intensive care unit (NICU) has an intestinal perforation, it is always necrotizing enterocolitis (NEC), right? Not so fast, my friend. Many of these preterm infants who perforate have free air from spontaneous intestinal perforation (SIP) and not NEC. As it turns out, not all free air in the NICU is NEC.  How can you tell the difference and does it matter?  

It can be challenging to tell the difference, but SIP tends to occur earlier in life, often within the first week, whereas NEC usually occurs slightly later. One analysis of a large data set showed the median age of onset of SIP was seven days after birth versus 15 days for NEC (1). SIP often occurs in babies who have never been fed or have only had trophic feeds, while many babies who develop NEC have had significant amounts of enteral nutrition or are on full feeds. SIP often presents with a relatively sudden onset of abdominal distention, not uncommonly with associated hypotension. NEC patients are more likely to have feeding intolerance or bloody stools noted before progressing to intestinal perforation.  

The physical exam can be different, too.  While infants with SIP and NEC will usually both have abdominal distention, those with SIP tend to have some bluish discoloration on the skin, whereas in NEC, the skin on the distended abdomen can be erythematous, with crepitus and induration in severe cases (2,3). Obviously, there is overlap in the physical exam between the two. But think of it this way: with SIP, the perforation comes first and necrosis, with inflammation, comes later.  With NEC, the inflammation and necrosis come first, followed by perforation.

On x-ray, SIP babies usually have just free air, without many other abdominal findings. NEC babies can have dilated intestinal loops, pneumatosis intestinalis, and sometimes a fixed dilated loop of bowel. If the baby has those, especially pneumatosis intestinalis, it is NEC and not SIP. 

The most definitive way to differentiate is by looking at the bowel in the operating room. SIP usually occurs in the terminal ileum and has normal bowel proximal and distal to the perforation – although it can occur in the jejunum or colon – while NEC will show abnormality of a more extensive section of intestine, with ischemic and necrotic areas.  

While the most definitive way is to look at the intestine, we often do not get the chance to see the bowel in these types of infants. For babies who weigh less than 1,000 grams, the treatment of choice if they have free air in the abdomen, regardless of whether it’s NEC or SIP, has usually been to place a peritoneal drain at the bedside. The classic teaching has been that a third never need another intervention, a third fail and need an operation (either acutely or for a stricture, later) and a third succumb. Some pediatric surgeons have seen that drain as just a temporizing measure and believe most will need a laparotomy later. Regardless, that recommendation might be changing. Forthcoming data suggest that even for babies less than 1000 grams, if the preoperative diagnosis is NEC, the better treatment is a laparotomy. If the diagnosis is SIP, placing a peritoneal drain is the way to go and will frequently be the only intervention needed. Stay tuned for more information about that. This would be a huge shift in our thinking of treatment which makes differentiating between the two, prior to intervening, even more important.

Even if there is some diagnostic uncertainty between SIP and NEC, all of our small patients need to be closely monitored. If the infant has SIP, the drain may be all the surgical treatment they need for now. However, in NEC, a drain might not help, and the baby can deteriorate after the drain as the disease progresses. A laparotomy might then be necessary, if the baby can tolerate it and has a reasonable chance of survival.  

So, does it matter if it’s NEC or SIP? If the above unpublished data is confirmed, it matters because it influences your choice of treatment and helps to counsel parents regarding outcomes.  Precision in diagnosis allows for precision in terminology which will give us an opportunity for precision in treatment. Finally, it makes a difference to your hospital statistics, which will please your hospital quality assurance chief. The disease process is different, which makes the terminology different, which (likely) makes the treatment different. Not all free air in the NICU is NEC. 

References

  1.  Attridge JT, Clark R, Walker MW, Gordon PV. New insights into spontaneous intestinal perforation using a national data set.  (1) SIP is associated with early indomethacin exposure.  J Perinatol 2006: 26:93. 
  2.  Kim, Jae H.  Neonatal necrotizing enterocolitis: clinical features and diagnosis.  In: Kim, Melanie S, and Abrams, Steven A, eds. UpToDate.  https://www.uptodate.com/contents/neonatal-necrotizing-enterocolitis-clinical-features-and-diagnosis?search=necrotizing%20enterocolitis&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2. Accessed July 10, 2020.
  3. Kim ES and Brand ML.  Spontaneous Intestinal Perforation of the Newborn.  In: Kim, Melanie S, and Garcia-Prats, Joseph A, eds. UpToDate.  https://www.uptodate.com/contents/spontaneous-intestinal-perforation-of-the-newborn?search=spontaneous%20intestinal%20perforation&source=search_result&selectedTitle=1~43&usage_type=default&display_rank=1. Accessed July 10, 2020. 
gastroschisis silo

Gastroschisis : Application of a preformed silo

The management options for gastroschisis involve either a primary operative closure under general anaesthetic or a staged closure with the aid of a custom or a preformed silo. The published results for each are similar and the initial management utilized, is often dependent on geographical location / center preference rather than interpretation of studies. This post explains the tips and tricks for application of the preformed Gastroschisis silo; ideal to know in general, but also a page of handy hints for 3am.

Where:

at the bedside and does not require a general anaesthetic.

Set up:

The patient should have iv access and be fully resuscitated. An NGT should be placed, on free drainage. Different units will have different guidelines on analgesia, sedation is not usually required, but some departments will give paracetamol pre-application.

Equipment:

preformed Gastroschisis silo, sterile gloves, plenty of gauze, warm saline. Preformed silos come in different sizes, for most term infants a size 4cm is the most appropriate. The size relates to the diameter at the base and silos are available in half cm sizes. Too small a silo and the ring can compress the bowel, too large a silo and the abdominal wall defect is stretched.

gastroschisis silo

Technique:

Inspect the bowel – there is no need to separate the loops or treat any potential atresia, but it is important to ensure there is no bleeding, no band that needs treating and that the bowel is viable.

Clean the skin – use warm saline soaked gauze to clean the vernix off the skin. The silo dressing needs to stick well to allow suspension and subsequent reduction of contents.

Finger sweep the edge of the defect – place a finger into the defect and go around the whole circumference to ensure there are no attachments. You can start anywhere, but if you always start in the same place, for example the superior aspect, it helps to ensure you check the full circumference.

Gastroschisis silo set up – place a few mls of sterile saline or sterile water into the silo. This helps to lubricate the silo and makes it easier to advance the bowel.

Insert the bowel into the silo – hold the silo with the wings at 6 and 12 o’clock and DO NOT rotate the wings for the procedure. If you rotate the silo, you rotate the bowel and risk volvulus and ischaemia. Start with the apex of the bowel and slowly advance the bowel into the silo until it is all inside.

Insert the silo (and wing) into the abdomen – squeeze the circular base of the silo and insert one edge into the abdominal wall. Systematically insert the rest of the ring into the abdomen.

Stick the Gastroschisis silo down – dry the abdominal wall skin and stick down the dressing over the wings of the silo. Be careful not to touch the adhesive side of the dressing – it is very difficult to get off gloves. The dressing can be stuck in any orientation, but we would suggest you place the gap in the dressing under the umbilical cord. 

Wrap the abdominal cord – keep the cord moist by wrapping in a non-adhesive dressing covered in cling film to prevent it drying out. The cord can be helpful in obtaining abdominal closure – which can be done sutured or sutureless. Some centres place the cord inside the abdominal cavity until closure.

Suspend the silo – place the cord through the top of the silo and attach to the top of the cot; depending on the type of cot, the cord can be tied over the cot or taped to it.

Staged Reduction of contents – again, different departments will have different protocols for reduction of contents, but effectively the silo is repeatedly squeezed over the next few days to reduce the bowel into the abdomen – we suggest the contents are reduced twice a day and ideally full reduction is obtained before 5 days. The silo is squeezed above the apex of the bowel and once the abdomen feels tight / no further reduction is possible at that point, a piece of cord tied above the apex of the bowel until the next reduction is due and the process repeated. Unit policy on analgesia should be followed.

Additional tips:

If when placing the silo it becomes twisted and it is difficult to know which flange should be at 6 and which at 12 o’clock, stop and start again. There is no problem with going back and restarting with the application of the silo, but you do not want to risk volvulus of the bowel.

If the defect is too small for the silo ring, the defect can be enlarged with an incision in the fascia – different people advocate midline or lateral. We go midline.

If the bowel looks discoloured in the silo: aspirate the NGT – if large aspirate, reassess after 15 minutes. If minimal aspirates or still concerned, reduce the pressure on the bowel by releasing the cord tie and reassess after a further 15 minutes. If neither of these help, remove the silo and upsize or make an incision in the fascia or progress to a different management option.

Double check that the NG is in the stomach and works to completely decompressed the stomach.

High Flow Nasal Cannula in the Surgical Patient

Morta Lapkus, MD and Paras Khandhar, MD

Beaumont Health, Royal Oak, MI, USA

No matter how much they want it, airway management and the decision to place a surgical patient on a ventilator should not just be for the PICU physicians to decide. The type of ventilation a patient receives can affect the surgical patient both positively and negatively. Could High Flow Nasal Cannula in the surgical patient be beneficial? Imagine a patient with an esophageal anastomosis that is extubated to CPAP. Now imagine the tears that would flow from the surgeon when they discover bilateral pneumothoraces and a blown-out anastomosis. Tragic. Therefore, we must weigh the risks and benefits of intubation versus the various respiratory adjuncts as a multidisciplinary group rather than territorial separatists.

 

It should come as no surprise that intubation and reintubation may result in significant consequences: prolonged care in the hospital, ventilator induced lung injury, ventilator associated pneumonia, increased use of sedatives, and an increased mortality. There are several adjuncts that can help prevent respiratory morbidity in children including blow-by or aerosol mask, nasal cannula, high-flow nasal cannula (HFNC), and noninvasive positive pressure ventilation (NIPPV), which is comprised of CPAP and BiPAP. All abbreviations aside, what these modalities do is to help provide a combination of oxygenation and ventilation without an endotracheal tube.

 

Seemingly one step up from nasal cannula, high flow nasal cannula (HFNC) is a type of noninvasive ventilation that provides patients with humidified, heated air at a high flow. HFNC, at approximately 0.5-2 L/Kg flow, reduces anatomic dead space, reduces airway resistance, maintains airway pressures, and increases mucus clearance.1 It not only provides a constant flow of oxygen, but helps remove CO2 and keeps the airways open with a small amount of positive pressure. HFNC is not all rainbows and unicorns, it has it disadvantages as well. HFNC can be detrimental in pediatric surgical patients if they cannot handle their secretions, are at risk for aspiration, or if they recently had gastrointestinal surgery – think about the “fictitious” esophageal anastomosis we discussed earlier. In spite of that, HFNC is much more comfortable and physically tolerable when compared to CPAP or BiPAP. Patients on HFNC can talk and sometimes even eat. The humidified air also decreases likelihood of dry mucous membranes that can become very sore. Two downsides: 1) there is no measurement of the pressure at the level of the airway2 and 2) the pressure delivered can be decreased if a patient’s mouth is open making the amount of pressure present quite variable.

 

Studies have shown that HFNC does indeed decrease intubation rate and therefore the associated complications listed above.3 It has also been used in post-extubation respiratory failure in order to prevent reintubation. Instead of intubating a patient, you may be able to support them enough using this non-invasive technology. Already popular in adult ICUs, HFNC is gaining popularity on the pediatric side too.

 

Your take-home point? It is not as benign as nasal cannula but not as malignant as CPAP or BiPAP. HFNC: prevention of tears from esophageal surgeons and it might just save your patient a reintubation and all the risks associated.

 

References:

1Mikalsen, I. B., Davis, P., & Øymar, K. (2016, July 12). High flow nasal cannula in children: A literature review. Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine. BioMed Central Ltd. https://doi.org/10.1186/s13049-016-0278-4

 

2Adjuncts in Respiratory Care. (2016). In Waldhausen, J., Powell, D., & Hirschl, R. (Eds.), Pediatric Surgery NaT. American Pediatric Surgical Association. Retrieved June 29, 2020, from https://www.pedsurglibrary.com/apsa/view/Pediatric-Surgery-NaT/829021/all/Adjuncts_in_Respiratory_Care

 

3McKiernan, C., Chua, L. C., Visintainer, P. F., & Allen, H. (2010). High Flow Nasal Cannulae Therapy in Infants with Bronchiolitis. Journal of Pediatrics156(4), 634–638. https://doi.org/10.1016/j.jpeds.2009.10.039

Readiness for Extubation for Pediatric Patients

Ameer Al-Hadidi MD¹, Morta Lapkus MD², and Paras Khandhar MD³

¹ Department of Pediatric Surgery, Nationwide Children’s Hospital, Columbus, OH, USA

² Department of Surgery, Beaumont Health, Royal Oak, MI, USA

³ Department of Pediatrics, Beaumont Children’s, Royal Oak, MI, USA

 

Why Should Surgeons Care?

Assessing the readiness for extubation for pediatric patients is not just the decision of the PICU doctors. It must require discussion and agreement of a multi-disciplinary team that includes the operating surgeon and intensivist for the best outcomes. Spontaneous breathing trials are the mainstay of assessing a patient’s readiness for extubation – the entire team must pay close attention to fully understand the readiness for extubation for pediatric patients.

Of course, there are the ‘straight forward’ patients intubated temporarily to obtain imaging, to undergo a necessary procedure, or for protecting an airway during an altered mental state. However, more complicated patients with significant comorbidities, substantial pulmonary contusions following chest trauma, or even a delicate proximal anastomosis, the decision to extubate from a ventilator cannot be taken lightly and must be approached in a multi-disciplinary fashion. 

We know patients who require reintubation following a failed attempt at extubation tend to have longer PICU length of stay, longer hospital length of stay, more likely to develop ventilator-associated complications, more likely to require discharge to rehab or long-term care facilities, and have a higher risk of mortality. Even though there has been a significant advancement in the development of respiratory rescue therapies (link to HFNC article) to support patients who are struggling to breathe on their own adequately, their success is not 100%. 

Extubation Indices 

The risk of a failed extubation in the pediatric population is 2-20%, comparable to adults at 10-23%. It’s pretty standard for patients in both groups to undergo a spontaneous breathing trial (SBT) to make sure they can maintain adequate ventilation and oxygenation, stable hemodynamics, and remain calm before attempting extubation. Indices like the rapid shallow breathing index (RSBI) and negative inspiratory force (NIF) are used regularly in adult intensive care units where RSBI is the most accurate predictor of adult post-extubation success, and NIF has a high negative predictive value. Unfortunately, none of these has held up in children, which makes the multi-disciplinary care of an intubated surgical patient even more imperative. 

Outside of sound clinical judgment, a systematic review of weaning and extubation of pediatric patients from mechanical ventilation failed to identify a single index, hint, or suggestion to make a surgeons’ job easier in improving the likelihood of extubation success. Paying close attention to any signs of cardiovascular compromise, increased respiratory effort with hypoxia or increases in end-tidal CO2, and any other signs of distress during an SBT are all cues that prognosticate failure. 

With approximately 30% of North American pediatric surgery training programs providing accredited critical care fellowships for trainees, pediatric surgeons are positioning themselves to contribute in the area of the critical care of infants and children. It is a mistake for surgeons to abdicate their role in critical decisions like the extubation of surgical patients.

 

References

Newth CJL, Venkataraman S, Willson DF, Meert KL, Harrison R, Dean JM, et al.: Weaning and extubation readiness in pediatric patients. Pediatr Crit Care Med 2009; 10(1):1-11

Frutos-Vivar F, Esteban A, Apezteguia C, González M, Arabi Y, Restrepo MI, et al.: Outcome of reintubated patients after scheduled extubation. J Crit Care 2011; 26(5):502-509

what’s our vector Victor

What’s our vector, Victor?   

 

Most surgical trainees look at their Chief and think, “Damn, you’re old,” because, in the middle of something important or complex the chief will say something random like, “what’s our vector, Victor?” The anaesthetist who is also as old as Mehtusulah will smile and this will prove to one and all that the Chief is a child of a bygone age. She really isn’t, she is just subtly trying to teach you about tying surgical knots properly, and why you should push into the wound not pull out of the wound. Vectors can be the difference between life and bleeding out horribly. Your Chief is wise.

 

“What’s our vector, Victor?” comes from an old (sic) film called “Airplane.” You should watch it, if only to understand why old people randomly say things like, “Surely you can’t be serious?” (I am. And don’t call me Shirley!) In terms of surgical knot tying understanding, vectors is everything. If you don’t you won’t understand why your knots are causing your Chief to sweat like Ted Striker. If you get vectors wrong, bad things will happen.

what’s our vector victor

This post is not about how one throws a knot. That will be found elsewhere. It is about how one tightens a knot and uses vectors to both secure the knot and stop the tissue being ligated from being ripped out of a deep dark, soon to be filled with blood, hole. A vector is a quantity made up of force and magnitude; the amount you pull and the direction you pull in. 

 

If you throw a knot and pull up on both ends in two separate directions, out of the wound, the resultant vector (red arrow) will cause tearing of the underlying tissue upwards, away from whatever essential structure is in the deep. Worse, the knot will not be fully locked either.

what’s our vector Victor

what’s our vector victor

If however, you hear your Chief’s voice in your head saying, “What’s our vector, Victor”  and then rotate one of the treads to push down on that, in completely the opposite direction from the pull out of the wound, the resultant vector will be a balance of both of these forces, ideally zero (red dot). Nothing will move with the exception of the knot locking and your Chief being impressed. (They won’t say they are impressed, they expect this.) But if you can achieve this, somewhere, deep inside, something will change, all because of vectors. What’s our vector, Victor? Roger, Roger.