Conference Reviews: Tuesday, May 20
Safe Sedation of the Obese Child
Reviewed by Patricia Scherrer, MD
The goals of this breakfast session were to:
Review the epidemiology and physiologic ramifications of obesity
Outline some of the risks associated with procedural sedation of the obese child, including the impact of co-morbidities and pharmacokinetic differences
Discuss possible options for making procedural sedation of the obese child safer
Propose potential indications for referral to pediatric anesthesiology
The session began with a case study illustrating the dilemma that many pediatric sedation providers face. This child was a nine year-old, with recurrent headaches as well as ADD and oppositional behavior issues, who presented for a sedated brain MRI, having been unable to tolerate laying flat in the scanner even with distraction. However, he weighed 130 pounds, which with his height yielded an absolute BMI of 29 or a BMI percentile for age and gender of greater than the 99th percentile. He had a history of snoring but no frank apnea, was able to lie flat on the bed without increased work of breathing, and had a Mallampati score of two. However, he did have significantly increased pre-tracheal adipose tissue. What should be done with a patient such as this?
As an introduction, we reviewed that obesity prevalence rates are up dramatically in the last 20 years, with a current prevalence rate per the CDC of 16.9% between two and 19 years of age. From a physiologic standpoint, we know that there is a higher incidence of oxygen desaturation in these patients at baseline, due to a combination of increased chest wall resistance, decreased respiratory compliance, decreased FRC, and higher closing volume to FRC ratio, all of which are exaggerated in the recumbent position when abdominal pressure on the diaphragm is highest. Co-morbidities are also much more prevalent, including obstructive sleep apnea, which is present in 13 to 59% of obese children, as well as asthma, hypertension, metabolic syndrome, GERD, and many others. Finally, obesity affects the pharmacokinetics of most sedatives and anesthetics, though we have very little pharmacokinetic information for children. Drug clearance may be altered, and the volume of distribution may be unpredictable. So, how do these factors impact clinical sedation practice?
There is some information in the anesthesia literature describing outcomes in obese children:
Setzer, Pediatr Anesth 2007 – more challenging mask ventilation and direct laryngoscopy, higher incidence of intraoperative desaturation, more frequent overnight hospitalization
Nafui, Pediatr Anesth 2007 – higher incidence of difficult airway, higher incidence of postoperative upper airway obstruction
Tait, Anesthsiology 2008 – higher incidences of difficult mask ventilation, airway obstruction, bronchospasm, major desaturation, and any critical airway event
Nafui, Pediatr Anesth 2010 – higher incidence of failed first and subsequent IV placement attempts
Currently, there is no published literature regarding the impact of obesity on procedural sedation outcomes, but the Pediatric Sedation Research Consortium has a paper submitted to Pediatric Anesthesia examining this topic. On retrospective review of 28,792 records entered in the PSRC database between September 14, 2008 and July 15, 2011, using the CDC definition of obesity as BMI greater than or equal to 95th percentile for age and gender, 5,153, or 17.9%, were obese. In the obese population, there was a statistically significant increase in adverse events, including airway obstruction, unexpected need for BVM, desaturation, secretions requiring treatment, failure to complete the procedure due to an IV related problem, laryngospasm, and prolonged recovery. There was no increase in unplanned hospital admissions, aspiration, emergent anesthesia consultation, cardiac arrest, or death. Obese patients did require more airway interventions, including repositioning, jaw thrust, suctioning, placement of oral and/or NP airways, and BVM. There was not a statistically significant increase in need for endotracheal intubation or LMA placement. Due to the retrospective nature of the study, it was not possible to evaluate the impact of co-existing obstructive sleep apnea or other factors on patient deferral practices.
With this information, how should a sedation provider approach the obese child requiring procedural sedation? Most attendees indicated that they attempted to obtain a height as part of their pre-sedation assessment prior to the child’s arrival. Is there a better way to screen these patients beyond absolute BMI or BMI percentile for age? Many participants described various questions to elicit a history of underlying obstructive sleep apnea as one of the key factors in choosing to proceed or defer. In general, thoughtful preparation is key, including:
Assuring access to the child’s airway and two person BVM if needed
Having airway adjuncts close at hand
Dosing many sedative/analgesics based on ideal body weight versus actual
Trying different patient positioning techniques
Planning for longer induction times and/or longer recovery times
Arranging backup personnel for maneuvering older patients if needed
Most folks would refer a patient to their pediatric anesthesiology colleagues if the child had a history of sleep apnea or other significant co-morbidities as well as longer procedures, especially those requiring supine positioning with limited access to the child’s airway, such as lengthier or more complex MRI scans.
Sedation and Anesthesia in Dentistry: Past, Present and Future
Reviewed by Cheri Landers, MD
Morton Rosenberg, DMD took us on a tour of the history of anesthesia starting with dentists Morton and Wells who administered the first anesthesia (ether) in Boston and to the “ether dome”, also in Boston.
Why do sedation and dentistry go together? Because people would rather do their taxes than go to the dentist! These fears likely stem from dental experiences in childhood. Dr. Rosenberg introduced us to the word “pre-cooperative”, the age during which a child is developmentally unable to cooperate in their medical/dental care. Definition of failed sedation: the child who wedged himself out of reach after oral midazolam then pulled the fire alarm upon exiting the dental office!
Sedation in the dental office for decades was unregulated. Comprehensive databases or closed claims are not available for dentistry. However, dental malpractice carriers, one in particular that covers 75% of all oral and maxillofacial surgery (OMFS) practitioners, do release data on claims. In these OMFS surgery offices, mortalities occur in 1 out of 380,000 cases and they estimate that one in 18 OMFS surgeons will have a patient with a major sedation/anesthesia event resulting in severe neurologic injury or death in a 30-year career.
In the 1970’s, due to reported deaths from anesthesia in dental offices, states began regulating providers and requiring permits to be able to provide anesthesia in the office setting. OMFS and dental anesthesiologists could meet the regulatory requirements, but dentists could not, so they abandoned anesthesia and opted for “safe, conscious” sedation instead. Soon, deaths were being reported from that practice as well. Now permits are required to provide sedation. Each state has its own requirements and regulates who can do what and where (office, hospital, etc.).
Deaths still occur from sedation and toxic overdoses of local anesthetics, especially in pediatric patients. Local anesthetics are packaged in set single dose vials that insert into the delivery device. This doesn’t allow for easy administration of only a portion of the vial. Dr. Rosenberg showed a dry erase board in an office exam room with pre-calculated medication doses written in for every possible imagined medication needed, from local agent to sedative to neuromuscular blockade. The “problem” with oral sedative medications is multiple repetitive dosing when adequate effect hasn’t been achieved, resulting in rapidly increasing plasma levels, which can last even through the post procedure period.
Cases of mortality due to sedation in dental offices have been related to little pediatric training in “regular” dental school programs, potential concerns about reimbursement for procedures performed in locations outside of the dental office, poor/inadequate monitoring, and inability to rescue.
Comments on Training
Dental Anesthesia training: three years long, 1.5 years of which is anesthesia with 100 cases
and < 7 years old.
OMFS training: five months in the OR, of which one month is pediatrics.
Dentists: minimal and moderate sedation is taught as part of educational requirements; those who did not receive the training in school get competencies through CE courses.
The American Dental Association and other organizations developed an Airway Management/Rescue Simulator and Training Course with assistance from a grant from an anesthesia research foundation which has funds to use as seed money for projects. Courses were developed with the help of the Medical University of South Carolina (MUSC) simulation center and are now working with centers nationwide.
There is a strong recommendation by the ASA to use end-tidal CO2 for monitoring all moderate and deep sedations. This is technically challenging in the dental office while administering nitrous oxide, but use of a combination oxygen delivery and end tidal CO2 cannula can work. Dr. Rosenberg highly recommended the use of a precordial stethoscope in addition to other traditional monitoring devices. Blue tooth varieties are available, giving the sedationist more “movability” during a case.
In summary, sedation and anesthesia in the dental office still occur with potential and actual poor outcomes. Appropriate training and monitoring are keys to the safe provision of sedation to the pediatric patient.
I’m Just a Kid! A Developmental Approach to a Quality Sedation Experience
Reviewed by Lorie Reilly, RN, MSN
Melissa Hale, CCLS and Betsy McMillan, CCLS gave a thought-provoking presentation about developmental approaches to consider with children who are being sedated. The perspective presented was through the eyes of the child and family, and highlighted what can be done pre-, intra-, and post-procedure. They described special considerations that affect the child and family coping and include the diagnosis, previous experience, misconceptions, expectations, special needs, temperament, coping style and family support. The concept of ONE VOICE was emphasized, along with support techniques and comfort holds as well as giving children choices when appropriate.
Awards Luncheon with Panel Discussion: Great Expectations-Defining Quality in Pediatric Sedation
Reviewed by Mark Buckmaster, MD
Great Expectations, with its literary allusion to the classic coming-of-age novel by Charles Dickens, was the overarching theme of the 2014 Society for Pediatric Sedation Conference and the specific focus of the Awards Luncheon panel discussion, “Great Expectations-Defining Quality in Pediatric Sedation.” The panel discussion reviewed the results from the November 2012 Society for Pediatric Sedation Consensus Meeting: Defining Quality in Pediatric Sedation held in Baltimore, Maryland under grant support from the AHRQ and The Mayday Fund.
The Consensus Meeting brought numerous sedation experts from across the country together to define the means to achieve excellence in pediatric sedation as defined under the Institute of Medicine’s six key aims. Each of the panelists was a group leader responsible for coordinating his or her group’s efforts within one of the six key aims. The panelists consisted of J. Michael Connors, MD (key aim: Patient and Family Centered Care); Lia Lowrie, MD (key aim: Safety); Susanne Kost, MD (key aim: Efficiency); Deborah LaViolette, RN (key aim: Timeliness); Joseph Cravero, MD (key aim: Effectiveness); Patricia Scherrer, MD (key aim: Equitability); and Cheri Landers, MD (Chair of the SPS Committee on Quality and Safety).
Each of the group leaders summarized the work that had been performed and updated the audience on forthcoming results from the ongoing reviews of the Consensus Meeting data. This has led to the development of a proposed Sedation State Scale which is currently under validation by Dr. Cravero at Boston Children’s Hospital, as well as a Family Satisfaction questionnaire being developed by Dr. Connors at Connecticut Children’s Medical Center among other innovative ideas. Dr. Landers then completed the discussion with how, under the auspices of her committee, the Consensus Meeting data would be applied to the development of specific goals to achieve global high quality pediatric sedation care. She concluded her presentation by encouraging the audience to participate in the Quality and Safety Committee’s activities. The luncheon concluded with a lively Q & A session between the audience and the panelists.
As Pip grew and matured over the course of Dickens’ novel, we can hope that the “Great Expectations” fostered by the Consensus Meeting will have a major impact on fundamentally improving pediatric sedation practice.