Thiopental: A Propofol Alternative?

There have been widespread reports of propofol shortages over the last several years.  This obviously creates a certain amount of anxiety in the anesthesia world given that propofol has become a common component of anesthetic regimens in the U.S.  However, the impact is also being felt, perhaps even more so, in the world of pediatric sedation.  Given the favorable characteristics of propofol, many pediatric sedation services have shifted almost entirely to a propofol based sedation regimen.

Despite all the anxieties, most places are still able to get propofol.  However, the question does remain… What would you do if you could not get propofol?  Would we revert back to oral chloral hydrate?  What about the pentobarb regimens we were all happy to leave in the past?

Dexmedetomidine is a viable option in many cases but most people would agree it is no propofol, especially from the standpoint of cost and recovery.  Interestingly, Dr. Gordon Gale from St. Louis University, has been using another regimen for years that approximates what we see when using propofol.  He describes his experience below.

Na Thiopental for procedural sedation

By Dr. Gordon Gale

In the 1980’s, prior to propofol, there was a necessity to sedate children for radiation therapy. At that time many children diagnosed with acute lymphoblastic leukemia required prophylactic CNS radiation. In addition, children with Wilm’s tumor, retinoblastoma, and sarcomas also required radiation. Obviously, the children had to lie perfectly still for a short period of time (<5 minutes).

In my primary role as a pediatric oncologist, I started using Na thiopental to sedate young children for RT. We originally used chloral hydrate which was not only inefficient but largely ineffective and unreliable. I had some experience with pentobarbital, but was not satisfied with the prolonged sedation for short procedures and the unpleasant awakening for many children who had to be sedated daily for up to 6 weeks. Some children needed to be sedated twice a day. Prolonged sedations left little time for the children to drink and/or eat between sedations.

With thiopental, the rapid onset of sedation and short duration of effect seemed to make it an ideal agent for these short procedures.  Originally, I administered 2-4mg/kg as a bolus and then aliquots of 1-2 mg /kg every minute or so until the desired state of sleep.  Obviously, the children were closely monitored.  Some children required as much as 10-12 mg/kg total for the procedures.  I sedated 5- 10 children every year for anywhere from 10 to 30 days of radiation.  Thiopental was very effective and I found it to be safe.  Once I arrived at an adequate dose for a child, this dose remained amazingly consistent from day to day and there did not seem to be any tachyphylaxis.

Subsequently, I started to use thiopental along with fentanyl (2-3 µgm/kg) for painful procedures such as lumbar punctures and bone marrow aspirates. I found this combination to be effective and reasonably safe, although a low percentage of children became apneic.  I subsequently began using ketamine which I found to be more effective and safer.

In the eighties and nineties, I used Na Thiopental for some long procedures such as MRI and nuclear medicine scans. After the children were initially adequately sedated, I would routinely give 1-2mg/kg every 10 – 15 minutes. More recently, when I use thiopental for prolonged procedures, I give an initial bolus dose of 2- 4mg/kg and then a continuous infusion of 8mg/kg /hour and occasionally increase to 10mg/kg/hr if necessary.  The initial sedation is almost always accompanied by a big yawn and then sleep. The induction is actually much smoother than with propofol with less agitation (no burn). Anecdotally, my observation is that there is less hypotension as well (no firm data).

I am sorry that I do not have any scientific data but I have a lot of experience with Na Thiopental and find it to be very effective and safe for procedural sedation.

Gordon Gale M.D.

Professor of Pediatrics

Cardinal Glennon Children’s Medical Center

St Louis University

Other Shortages

It turns out that the current supply of Na Thiopental is not any more robust than that of the propofol.  However, these things are always changing.  It does seem that for certain select patients (severe egg allergy) or maybe even to bridge a temporary interruption in the supply of propofol, Na Thiopental might be an excellent alternative.

Thanks to Dr. Gale for sharing his experience with us on this innovative approach to quality sedation care for children.

Pediatric Sedation Rotation

There has been a fair bit of discussion regarding the need for a pediatric sedation rotation.  Currently sedation is not mentioned anywhere by the American Board of Pediatrics or in the specific training requirement issued by the ACGME & RRC.  As such, many programs that have identified a need for this training must attempt to incorporate it into a pediatric anesthesia rotation or offer it as a separate elective.

For many programs though residents get the bulk (if any) of their sedation experiences as part of an ER or ICU rotation.  Since the need for sedation in these locations is somewhat unpredictable, it may leave many pediatric residents finishing their residency with neither the skills to safely provide sedation nor a proper understanding of the issues surrounding outpatient procedural sedation.  In our institution most graduating residents report 0-5 sedation encounters.  This is just not sufficient to develop any sort of competency in this important area of pediatric practice.

The Challenge

This presents a challenge for many of our pediatric colleagues who enter general practice.  The sedation process begins with the ordering physician.  For those of us non-anesthesiologists who provide procedural sedation outside the operating room, we know the most important aspect of our practice is proper patient selection.  This process begins in the general pediatricians office, when the decision is made about what test to order and the need for sedation, general anesthesia, or perhaps a skilled non-pharmacological approach.

This also represents a challenge for the pediatric hospitalist.  Given the shortage of pediatric anesthesiologists, intensivists, and ER docs, the responsibility of providing pediatric sedation is increasingly falling upon the shoulders of the pediatric hospitalist.  This is especially true in smaller community centers where these subspeciality resources are particularly scarce.

When I attended the Sedation Provider Course offered by SPS in May of 2009, the overwhleming majority in attendance were pediatric hospitalists.  Given that many pediatric hospitalists have no additional training following their general pediatric residency, it begs the question… Where will they get the experience and training needed to provide this important pediatric service?

All of this to say, I think all pediatric residents would benefit from formal training in sedation.  This seems to be the consensus on the Listserve as well.  What exactly does this mean?  I think this question is a difficult one to answer.  In general, I think this means that we as Sedation Providers and Members of the Society for Pediatric Sedation need to pursue options to have sedation training move from non-existent (or sporadic at best) to a formal RRC requirement.

The Solution

I think Joe Cravero and Jennifer O’ Flaherty with the PainFree Program at Dartmouth have taken the first steps toward an effective solution.  They have a formal sedation rotation that all pediatric interns take.  It comes complete with objectives, exams, didactics, and practical skills.  The Primer of Pediatric Sedation is the foundation of the curriculum.  It seems to me that this is a model we could all attempt to weave into the resident curriculum at our own institutions.  Ultimately though, it really needs to be a formal part of pediatric residency training.  Exactly where to place it in that already complicated list of requirements remains to be seen. Continue reading

CMS Guidelines: Threat or Opportunity?

New guidelines have been released from Centers for Medicare & Medicaid Services related to “Anesthesia” services.  These guidelines have set off a firestorm of emails, letters, questions, and overall confusion to what they truly mean, what is their intention and how should these “interpretive” guidelines be interpreted.

The Society for Pediatric Sedation was one of many organizations that wrote to CMS, and expressed our opinion about the positives and negatives of these guidelines.  Our letter can be found here.

How has your institution approached these guidelines?

Has it been used as a threat to change your entire bylaws, sedation structure and deem “one physician” as the “controller” of  Anesthesia/Sedation? Has it been seen as “much ado about nothing” with no significant change seen based on your current structure? Has it brought specialties together or separated them further on this very important issue?

Overall, how do you feel it has or will impact patient care in your institution?

In my institution, it is yet to be determined.  Early on, I would readily admit that the confusion and difference of opinion led to some “tension” and mildly heated discourse.  Time will tell as the administration seeks to find clarity and answers to this dilemma.

The Opportunity

Overall, however, I see this as a great opportunity for improved sedation care.  Of course, this opportunity can only be seized if the anesthesia department and sedation service both feel that collaboration is truly what these guidelines are promoting.  The opportunity for anesthesia to provide oversight, input and collaboration is far different than an effort to take “control” or take back sedation care that they could not or did not want to provide many years ago thus allowing skilled expert sedation providers to fill this niche.

On the other hand, sedation services have an opportunity to promote very important dialogue with their anesthesia colleagues.  They should work to integrate care and not seen as a competitive services but rather a complementary one.

Our Hope

My feeling is that these guidelines can be interpreted very differently and “bias” clearly affects one’s vision.  However, if we are truly focused on “what is best for the patient” we can only hope that visions will clear, weapons will be dropped, and we will look back at these guidelines as an opportunity to promote multidisciplinary collaboration and improve sedation care.

High hopes perhaps, but perhaps a lofty goal that we as a society should strive for.

The SPS would appreciate your thoughts, opinions and experiences on this matter.  Please share via this Blog.  As a society we will continue to work to dialogue with Joint Commission, CMS and other agencies to meet our goals of improving sedation quality and safety.

Mick Connors MD

Intranasal Dexmedetomidine

Dexmedetomidine is a potent α-2 agonist with sedative and analgesic properties. Dexmedetomidine exhibits α-2:α-1 specificity that is eight times greater than clonidine.  Its’ sedative and anxiolytic properties are a result of its α-2 receptor specificity in the spinal cord and central nervous system.  Dexmedetomidine has a much shorter half life than clonidine (2-3 hours vs. 12-24 hours).  This pharmacokinetic profile can facilitate brief periods of deep sedation often needed for imaging procedures in pediatric sedation.

Use in MRI

Evidence supports the use of dexmedetomidine for sedation in mechanically ventilated adult patients.  There has been increasing interest in the clinical application of dexmedetomidine in the pediatric population.  High dose dexmedetomidine (3mcg/kg IV load over 10 minutes with an infusion of 1 mcg/kg/hour) has been used successfully for sedation of children undergoing sedation for MRI.  Using this dose, Mason et al noted bradycardia and a 20% drop in blood pressure with minimal change in respiratory parameters.

Buccal and Intranasal

Antilla et al documented the high bioavailability(73%-92%) when dexmedetomidine was given via the buccal route.  Onset occurred in 10-15 minutes with a peak effect at 90 minutes.  Yuen et al demonstrated the efficacy of intranasal dexmedetomidine when used in a dose of 2mcg/kg as a premedication.  Others have found dexmedetomidine, when used in a dose of 2 mcg/kg intranasal, to be an equivalent premedication to 0.5 mg/kg of po midazolam.

Our Experience

On the basis of this information, we have used intranasal dexmedetomidine as a premedication in a number of patients.  Since this drug has a neutral pH it is virtually painless when given intranasally. In addition, the use of the nasal MAD (mucosal atomization device) has allowed quick and even administration of the drug.

We reported the case of an uncooperative 10 year old autistic child that was scheduled for MRI under general anesthesia in which we gave a dose of dexmedetomidine (4 mcg/kg IN) as a premed to assist in further care.  Given this dose, this child calmed and fell asleep in the stretcher within 20 minutes.  Minimal change in heart rate and blood pressure were noted.  The child in fact slept through the duration of the scan without additional medication or anesthesia.  He was recovered in the PACU for an hour and was discharged.

Since then, we have used the dose of 4 mcg/kg IN for short scans (CT) with success.  We have also used this for ABR’s and repeated half the dose IN if the patient aroused during the study.  It should be noted that for intranasal administration we use the undiluted product which is 100 mcg/ml.  This allows for administration of a small volume which is dispensed quickly.

Further Study

All of this is anecdotal and should be studied further.  However, it is my belief that IN dexmedetomidine given alone or in combination with another drug such as ketamine may have broad application for sedation in children.  I suspect that this type of sedation would work well for dental procedures, EEG, EMG, PICC line placement, and imaging such as VCUG.

Joyce Phillips, MD, FAAP
Associate Professor
Department of Anesthesiology
University of New Mexico

Do you have experience with IN Dex?

For those who are already using IN Dex, please take a moment to make a brief comment below about your experience.

How do I use the MAD device?

Below is a link to a video that describes the use or the MAD.

MAD Video

Other Useful Articles

High Dose Dexmedetomidine as the Sole Sedative for Pediatric MRI

Dexmedetomidine for Pediatric Sedation for CT Imaging Studies

Intranasal Dexmedetomidine for Sedation during CT Scanning

Bioavailability of Dexmedetomidine after Extravascular Doses in Healthy Subjects

Buccal Administration of Dexmedetomidine as a Preanesthetic in Children

A Double-Blind, Crossover Assessment of the Sedative and Analgesic Effects of Intranasal Dexmedetomidine

A Comparison of Intranasal Dexmedetomidine and Oral Midazolam for Premedication in Pediatric Anesthesia

Intranasal Dexmedetomidine Premedication is Comparable with Midazolam in Burn Children Undergoing Reconstructive Surgery

SPS and Sir William Osler

As the inaugural blog posting of the Society for Pediatric Sedation, I felt it only appropriate that we understand the historic significance of this development in modern medicine. Modern medicine continues to evolve and specialism is alive and well in America as suggested and discussed by Sir William Osler in his address to the emerging Pediatric Society in 1892.

If you have not read this address, I would highly recommend taking the time to do so, it can be found at http://mcgovern.library.tmc.edu/data/www/html/people/osler/index.htm . It was published in the Boston Medical and Surgical Journal Vol 126:19, 457-459. I will utilize this blog to highlight some of the remarkable similarities of Sir Willam Osler’s address and the development of this Society for Pediatric Sedation some 120 years later. Continue reading