newsletter of the Florida Dental Society of Anesthesiology

Fall 2009

Marcos Diaz, DDS, President

Don’t miss the FDSA Continuing Education Seminar

Saturday, February 27, 2010!featuring Dr. Charles Kates

The Hilton Walt Disney World Resort, Orlando, FloridaSee pages 2 and 8 for details!

President’s Message

The FDSA wants to thank everyone who attended our Annual Meeting last March with Dr. Dan Becker. The meeting was an overwhelming success both in respect to its attendance as well

as from an informational content point of view. Most participants in their evaluations felt it was an extremely well-put-together, enjoyable seminar. Kudos to all! It was the best attended meeting ever for the FDSA.

As always once a meeting is done, preparation for the next one begins. Our next meeting’s lecture topic will be The Art & Science of Inhalation Anesthesia and Airway Management. Dr. Charles Kates, attending anesthesiologist at Jackson Memorial Hospital in Miami, will be lecturing. He is a well known Oral and Maxillofacial Surgeon who is not only a fine national and international speaker and academician, but an excellent clinician as well. He will speak on practical usage of anesthesia delivery systems, vaporizers, breathing circuits, IV pumps, ventilation and ventilators, pharmacology of inhalation anesthetics and related drugs, as well as basic and advanced airway emergency management principles and techniques for both children and adults. Extensive use of video will be employed to enhance the learning process. For any of you who have heard him speak before, his audiovisual presentations are superb, which synergistically complement the material presented and thus superbly enhance its understanding.

I am currently in my second year as President of the FDSA, and it has not only been an extremely enlightening experience but a rewarding process in the making. I would encourage anyone from the active membership to consider joining the executive board. All it takes is a desire, commitment in showing up at our meetings and a little work. As Woody Allen used to say “The world is run by people who show up!” If there are any members who would be interested in helping guide and actively participate in the development and continuation of this wonderful organization, please get in touch with either me or any of our Board Members at any time; we want to encourage anyone to join. Please consider giving something back to a society that has given you much.

Finally, on behalf of all the FDSA Board Members, I would like to take this opportunity to personally thank Ms. Tricia Cross, the Administrative Director, for all the effort, hard work and dedication she has brought, and continues to bring, to this organization. She needs to be commended not only for what she has done over the past two years in this Society, but her indefatigable drive and always overwhelming creativity which has allowed us to become much of what we are today. Tricia, we thank you so much for always being there for us with such a great attitude and disposition.

Humbly yours, Marcos Díaz, DDS

Florida Dental Society of Anesthesiology

�

FDSA 2010 ANESTHESIA SEMINARSaturday, February 27, 2010

The Hilton Walt Disney Resort, Orlando FloridaThe Art & Science of Inhalation Anesthesia and Airway Management

with Dr. Charles KatesWe are proud to announce that Dr. Charles Kates will present our annual Continuing Education Seminar, Saturday, February 27, 2010, at the Hilton Walt Disney World Resort, Orlando, Florida. Dr. Kates, a nationally recognized lecturer, will provide doctors the opportunity to upgrade their knowledge on topics of critical importance within our profession. His topic is titled: “The Art & Science of Inhalation Anesthesia and Airway Management”.

The course will include practical usage of anesthesia delivery systems, vaporizers, breathing circuits, IV pumps, ventilation and ventilators, pharmacology of inhalation anesthetics and related drugs, and basic and advanced airway emergency management principles and techniques for both children and adults. Extensive use of video clips will be employed in order to enhance the learning process so that the student will have a complete understanding of the systems and methods presented.

After completing this course, attendees will have:

An understanding of anesthesia apparatus and associated equipment for practical application to every day office practice;

An overview of inhalation anesthesia and anesthetics, including associated medications;

A detailed and high level understanding of the principles and techniques of airway management and associated airway emergencies;

An appreciation of the value of inhalation anesthesia as an important modality for provision of office based anesthesia.

The course will provide doctors with 6 continuing education credits and fulfill the Board of Dentistry’s 4 hour biennium requirement for sedation and anesthesia permits, including the anesthesia emergency component. FDSA courses are also approved for AGD CE credit (AGD provider ID 315124).

FDSA is proud to have Dr. Charles Kates present the 2010 Continuing Education Conference. Dr. Kates is a superb presenter, known widely for his excellent audiovisual presentations which greatly enhance his seminars.

Dr. Kates is Associate Professor of Anesthesia and Surgery and Director Anesthesia and Pain Control, Section of Oral/Maxillofacial Surgery and Dentistry,

Department of Surgery, and Associate Faculty, Department of Anesthesia, Jackson Memorial Hospital, University of Miami Miller School of Medicine. He is an Attending Anesthesiologist and Surgeon at Jackson Memorial Hospital. Dr. Kates is also Associate Professor, Department of Family Practice, and Lecturer, Department of Oral/Maxillofacial Surgery, at Nova-Southeastern University School of Dentistry. Dr. Kates is in private practice, Oral/Maxillofacial Surgery, in North Miami Beach, Florida.

Registration and hotel information may be found on the FDSA website, www.fdsahome.org

1.

2.

3.

4.

Questions? Email tricia@fdsahome.org

Fall �009

�

FDSA Board of Director’s Meeting A Board of Director’s meeting was held Saturday evening, July 25, 2009, during the Florida Society of Oral and Maxillofacial Surgery annual meeting. The Society’s financial status and membership status were reviewed and both are healthy and continue to grow. The proposed 2009 – 2010 operating budget was reviewed and approved. Plans were made for potential speakers for the upcoming 2010 and 2011 annual CE seminars, and plans for offering a SimMan course in Florida were discussed. The FDSA will sponsor the SimMan anesthesia emergency course, in coordination with the ADSA, at a location still to be determined, in the fall of 2010. Nominations for new officers were reviewed. Copies of the meeting minutes are available to members from Tricia Cross.

Our annual business meeting was held in conjunction with the FDSA annual meeting in March. Our next annual business meeting will be held following the FDSA annual CE seminar February 27, 2010. All members are invited to attend this meeting with the executive board at which we discuss future meeting plans, review legislative and Board of Dentistry actions affecting dental anesthesia. We will also review the society’s finances, and elect new officers for the next term starting summer of 2010. Anyone interested in becoming involved at the board level with the FDSA should plan to attend these meetings to become familiar with the FDSA organization and its’ functions.

Request For Papers, FAQ’SWe encourage you to submit any clinical articles on sedation, anesthesia, or management of emergencies that you feel may be of interest to other members. Also please submit any questions you may have about anesthesia practice, rules and regulations, the FDSA, or any other relevant issue to us. Submissions should be sent to the editor by email at: jawdoc0@aol.com.

Dental Experts Sought by Board of Dentistry

The Probable Cause Panel of the Florida Board of Dentistry is currently seeking and reviewing applications from actively practicing dental anesthesiologists who would be willing to serve as dental experts. Dental experts are integral for the Florida Department of Health and the Florida Board of Dentistry as each expert skillfully assists them in the review of complaints and cases that are filed against Florida dentists. Detailed information and an application can be found on the FDSA website: www.fdsahome.org or you may call Irene Lake in the Expert Witness Office of the Florida Department of Health at 850-245-4640, ext. 8212

Board of Dentistry Anesthesia Committee

The Board of Dentistry’s Anesthesia Committee met August 31, 2009 and FDSA was represented during the meeting by Dr. Clive Rayner, Dr. Marcos Diaz, and Dr. Don Tillery, Jr. The Committee made several motions that will be referred to the Board of Dentistry for final action.

The Anesthesia Committee approved a motion that an anesthesia permit applicant’s office evaluation sedation case must be a dental or OMS case, not a medical procedure, in cases where the applicant is dually licensed as a DDS and an MD.

The Committee made a motion to look into the possibility of training and permitting for certified anesthesia assistants to perform venipuncture and also to administer IV medications under direct and immediate supervision of the trained and permitted dentist.

The Committee made a recommendation that office anesthesia assisting staff be part of the biennial anesthesia and medical emergency training requirement.

The Committee reviewed and discussed a request from the Dental Organization for Conscious Sedation (DOCS) to separate enteral conscious sedation from parenteral conscious sedation training and permitting. Currently there are a few states that have separate provisions for enteral sedation permitting, but the Board felt that sedation should continue to be regulated based on the depth of sedation, not the route of administration. The Board of Dentistry believes that single dose / single agent minimal sedation (anxiolysis) should not require permitting, but the Committee did agree to the suggestion that there should be some written guidelines for patient evaluation, monitoring, and record keeping. A motion was made to develop such written guidelines. These issues will be brought forward at the next full Board of Dentistry meeting for discussion.

1.

2.

3.

4.

Board of Dentistry News

Florida Dental Society of Anesthesiology

�

2009 FDSA CE Conference – A great success! An excellent speaker, hospitable venue, and huge turnout of doctors and dental/surgical assistants combined to make the FDSA 2009 Continuing Education Conference one of the most successful ever! Dr. Dan Becker entertained and informed a record audience of 320 doctors and dental/surgical assistants at the March 14, 2009 conference with his presentation entitled “Pre-op Medical Evaluation of the Anesthesia Patient & Management of Anesthesia Emergencies”.

Conference evaluations were overwhelmingly positive. No doubt FDSA will have Dr. Becker return in the future!

A big thanks to our 2009 Platinum sponsor, Stryker CMF for their support and participation.

Stryker is one of the world’s leading medical technology companies with the most broadly based range of products, including: implants used in joint replacement, trauma, craniomaxillofacial and spinal surgeries; biologics; surgical, neurologic and interventional pain equipment; endoscopic, surgical navigation and communications systems as well as patient handling equipment. Contact Stryker CMF Representative, Dave Reiman at 407-625-2594. You may also call Stryker Customer Service at 800-253-7370, or visit their website, www.stryker.com.

“Dr. Becker is a superb teacher! Practical yet academic, a great presentation!” -- Dr. Randy Caton

“I think the FDSA does a good job with topics and speakers. This conference was well worth my time.” -- Dr. Kerry Waldee

“Becker was great!” -- Dr. Jim Horner

Fall �009

�

Thanks again to Dr. Marcos Diaz, we offer in this issue another excellent clinical article, this time on the science behind the use of capnography. Dr. Diaz’s article focuses primarily on patients with an endotracheal tube or an LMA in

place, and capnography now has a long history of such use and has gained universal acceptance in these patients. However, it is important to realize that capnography is also extremely useful (invaluable, those of us who use it every day would say) in non-intubated sedated dental patients. Our next issue will include a practical, clinical article discussing the everyday use of capnography in non-intubated patients, in whom its use is arguably even more important!

On another note, many of our members are familiar with DOCS (the “Dental Organization for Conscious Sedation”), a for-profit company teaching enteral conscious sedation in weekend courses, that recommends a technique of repeated oral dosing. DOCS approached the Florida Board of Dentistry at its last meeting, to request that the Board lower its sedation regulation and permitting standards. They do this on a regular basis, and the Board always gives them a fair hearing. Fortunately, there are several dentists on the Florida Board that have anesthesia training and a good understanding of the issues, and the Board declined to “water down” our state regulations.

As many of you know, our current sedation rules in Florida are set at a higher standard than the minimal ADA guidelines. There are many reasons for keeping this higher standard of care, and I’ll summarize just a few here.

Our state guidelines are based on the American Society of Anesthesiologists recommendations. The ASA standards are based on regulating sedation by depth, not by the route of administration. It is the depth of the anesthesia that determines the risk to the patient, not the route of administration of the drug. And safety of the patient is always the most important issue. Access to care for fearful patients is also important, but safety will always trump access to care as an issue.

ASA guidelines call for sedation training to include the ability to rescue a patient from the next deeper level of sedation, i.e. from inadvertent deep sedation if conscious sedation was planned. This requires more than a weekend course watching videos of sedated patients.

Physicians without formal anesthesia training cannot give deep sedation without an anesthesiologist, and must prove competency and training to give conscious sedation, even in the hospital setting, which is arguably safer than the office setting. We can’t have a lower standard.

The FDSA exists to promote the use of sedation in dentistry and to foster education in sedation and anesthesia, and we are always in favor of education from any source. We applaud the efforts of “DOCS” to promote the use of sedation in dentistry, and applaud also the improvements in the education they provide. They have come a long way since their first courses, in which they spent 80% of their time teaching marketing and only 20% on clinical education. But we disagree with some of the techniques they continue to teach, such as the titration of

oral agents. If a patient is not adequately sedated with an oral agent, rather than give repeated oral doses, it’s time to switch to another technique. We also believe that anyone teaching anesthesia should themselves be formally trained and certified in anesthesia.

A vehicle already exists for post-graduate training in conscious sedation. There are many programs across the country that offer 60 hour / 20 case courses in parenteral and enteral sedation that meet the Florida Board of Dentistry guidelines. These two week courses, while not as ideal as learning sedation in a

full-time residency, offer a means to gain hands-on experience and the minimal depth of didactics that is needed to be a safe practitioner. They offer the practitioner the opportunity to learn a variety of sedation techniques, because in anesthesia, it’s not “one size fits all.” Even if the practitioner only wants to provide enteral sedation, it’s always better to have more training than less. Otherwise, as the saying goes, “if all you have is a hammer, then everything looks like a nail.”

Sedation is a privilege that dentists have had and safely preserved since the days of Horace Wells. It would only take the death of one patient with enteral sedation, and all of dentistry could be tarred and feathered on the next “20 /20” television episode. Then we risk losing our sedation privileges and all of dentistry and our patients would suffer. For these reasons, it is always better to regulate ourselves and keep our standards high, than to have the government or the lawyers step in and decide it for us.

Comments from the Editor by Clive Rayner, DMD

Florida Dental Society of Anesthesiology

�

Upcoming Dental Anesthesia Seminars and Meetings

How To ReacH Us

We welcome your questions, comments, suggestions, and letters to the editor. You may contact us at the following:

Marcos Diaz, DDS President, FDSA 2239 Commerce Parkway, #2 Weston, FL 33327 954-659-9990 email: mdiaz@facialsurg.cc

Clive Rayner, DMD Executive Director, Editor, & Past-President, FDSA, 2301 Park Avenue, #101, Orange Park, FL 32073, 904-269-5195, email: jawdoc0@aol.com

Tricia Cross Administrator & Webmaster, FDSA P.O. Box 444, Orange Park, FL 32073 904-703-4083 email: tricia@fdsahome.org

Knight Charlton Executive Director, ADSA 211 E. Chicago Ave, #780, Chicago, IL 60611 800-722-7788 web: www.adsahome.org

FSOMS (Florida Society of Maxillofacial Surgeons); www.fsoms.org, 2009 Fall Meeting, Marriott World Center, Orlando, FL, November 12-15, 2009

AAOMS (American Association of Oral & Maxillofacial Surgeons), www.aaoms.org, Anesthesia Assistants Review Course, Sheraton Chicago Hotel & Towers, Chicago, IL, December 5-6, 2009

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, ADSA Chicago Review, The Renaissance Hotel, Chicago, IL, December 5-7, 2009

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Human Simulation, The Renaissance Hotel, Chicago, IL, December 5, 2009

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, General Anesthesia, The Renaissance Hotel, Chicago, IL, December 6-7, 2009

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Assistant Sedation/Anesthesia Course, The Renaissance Hotel, Chicago, IL, December 6-7, 2009

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, ADSA Las Vegas Reviews, Caesar’s Palace, Las Vegas, NV, February 25-27, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, General Anesthesia, Caesar’s Palace, Las Vegas, NV, February 26-27, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Human Simulation, Caesar’s Palace, Las Vegas, NV, February 25, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Minimal and Moderate Sedation Review, Caesar’s Palace, Las Vegas, NV, February 26-27, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Assistant Sedation/Anesthesia Course, Caesar’s Palace, Las Vegas, NV, February 26-27, 2010

FDSA (Florida Dental Society of Anesthesiology); www.fdsahome.org, 2010 CE Conference, The Art & Science of Inhalation Anesthesia and Airway Management, Hilton at Walt Disney Resort, Orlando, Florida, February 27, 2010

ASDA (American Society of Dentist Anesthesiologists): www.asdahq.org, Annual Scientific Session & House of Delegates, Fairmont Olympic Hotel, Seattle, WA, April 15-17, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, ADSA Annual Session, Ritz Carlton, Key Biscayne, FL, April 29-May 1, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, General Anesthesia, Ritz Carlton, Key Biscayne, FL, April 29-May 1, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Human Simulation, Ritz Carlton, Key Biscayne, FL, April 30, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Assistant Sedation/Anesthesia Course, Ritz Carlton, Key Biscayne, FL, April 29-30, 2010

ADSA (American Dental Society of Anesthesiology): www.adsahome.org, Small & Scary: Anesthesia for the Pediatric Patient (w/AAPD), Ritz Carlton, Key Biscayne, FL, April 29-May 1, 2010

AAOMS (American Association of Oral & Maxillofacial Surgeons), www.aaoms.org, Anesthesia Update for the OMS, McCormick Place West, Chicago, IL, September 28-29, 2010

FSOMS (Florida Society of Maxillofacial Surgeons): www.fsoms.org, 2010 Fall Meeting, Marriott World Center, Orlando, Florida, November 12-14, 2010

ADSA/IFDAS (International Federation of Anesthesia Societies) Kona/Kohala Coast, Hawaii, February 2-5, 2012

Fall �009

�

Welcome New FDSA Members!Daniel Drake, DDS of Ormond Beach, FL, General Practice

Pablo Martinez, DMD of Orlando, FL, OMSJohn Seasholtz, II, DMD of Tallahassee, FL, General Practice

F. Steven Sutherland, DDS of Trinity, FL, General Practice

FDSA MISSIONTo affiliate in one organization those dentists who are especially interested in anesthesiology, and anxiety and pain control.

To continually raise the standards of practice of dental anesthesiology to ensure that the highest standard of care is provided to the public.

To advance the art and science of pain and anxiety control as an integral part of dentistry.

To promote and sponsor scientific and educational seminars for the continuing education of the membership.

To meet for the purpose of exchanging information and report progress in the field of anesthesia and pain control.

To represent dentists engaged in the practice of office anesthesia to the public, to other professional organizations, and before regulatory agencies.

•

•

•

•

•

•

FDSA OFFICERS:

President Marcos Diaz, DDS

Vice President Charles Llano, DDS

Secretary & Treasurer Don Tillery, Jr., DMD

Officer at Large Sylvia Boyd, DDS

Executive Director Clive Rayner, DMD

Administrator & Webmaster Tricia Cross

Editor Clive Rayner, DMD

ADSA Delegates Clive Rayner, DMD

Lance Grenevicki, DDS, MD Marcos Diaz, DDS

Nitrous Oxide Safety Awareness Week Clive Rayner, DMD, Editor

Dr. Horace Wells, a dentist from Hartford, Connecticut, is regarded as the discoverer of anesthesia by virtue of being the first person to administer an anesthetic, in the form of nitrous oxide, on December 11, 1844. In honor of Dr. Wells and the 155th anniversary of the discovery of nitrous oxide, the ADSA has dedicated the week of December 6 - 11 as Nitrous Oxide Safety Awareness Week.

Today, approximately half of the dentists practicing in the United States routinely use nitrous oxide sedation for their patients. Nitrous oxide has a long history of safety in dentistry, but there are still occasional reports of hypoxic complications from crossed oxygen and nitrous oxide supply lines. The Pin Index Safety System, color coding of gas tanks, and the standard of using 1/2 inch lines for oxygen and 3/4 inch lines for nitrous oxide have greatly decreased the chances of error, but it still occasionally happens.

In fact, it happened to me. In my own old office 20 years ago, we replaced the central manifold. The next day, while performing a conscious sedation on a healthy ASA I patient, I noticed that the patient’s oxygen saturation was far lower than anticipated, and when I increased the oxygen to 100%, her saturation dropped further. I took the mask off the patient and held it to my nose and smelled pure nitrous oxide. Fortunately the patient was lightly sedated, we pulled in the portable oxygen tank we keep for emergencies, placed it on the patient and she immediately returned to a saturation of 100%. If that had been a general anesthetic it could have been catastrophic. It turns out that even though I used a well-known “certified gas contractor” at the recommendation of my dental equipment supplier, he had crossed the supply lines, and never tested the system. In fact, he didn’t even know what an oxygen analyzer was. I bought my own oxygen analyzer the next day and now I periodically measure the oxygen output at each anesthesia machine. Don’t trust your contractors; test the systems yourself!

What better way to honor Horace Wells and Nitrous Oxide Safety Awareness Week than to test and assure that your nitrous oxide equipment is functioning correctly?

Join Us In Orlando! 2010 Annual Continuing Education Seminar

Saturday, February 27, 2010 8:30 am - 4:00 pm

6 hours CE credit

Hilton Walt Disney World Resort,

Orlando, Florida

The Art and Science of Inhalation Anesthesia

and Airway ManagementPresented by Charles H. Kates, DDS

Experience ...

... the magic of Disney!

In these tight economic times, earn your required CE credits

at a convenient one-day seminar in Florida!

This course fulfills the Board of Dentistry’s 4 hour biennium requirement for sedation and anesthesia permits, including the anesthesia emergency component.

THE CURRENT FLORIDA BIENNIUM ENDS FEBRUARY 28, 2010!

Capnography 101: A PrimerBy Marcos Díaz, D.D.S.

A: Normal capnograph. I: Dead space expiration; II: Mixed dead space and alveolar gas expira-tion; III: Alveolar gas expiration and plateau; 0: Inspiration. Phase IV is a terminal upswing that occurs at the end of Phase III seen in obese and pregnant patients with reduced thoracic compliance.

B: Capnographs that may be seen in practice. 1: Rapid extinguishing uncharacteristic waveform compatible with esophageal intubation; 2: Regular dips in end-expiratory plateau seen in underventilated lungs or in patients recovering from neuromus-cular blockade “Curare Clefts”; 3: Upward shift in baseline seen with rebreathing of CO2, miscalibration, etc.; 4: Restrictive pulmonary disease; 5: Obstructive pulmonary disease; 6: Cardiogenic oscillations usually seen with sidestream capnographs for spontaneously breath-ing patients at the end of each exhalation. The cardiac action causes a to-and-fro movement of the interface between exhaled and fresh gas.

Figure 1.

Since its introduction in anesthesia thirty years ago, cap-nography has demonstrated its usefulness in detecting respiratory events which has helped tremendously in the delivery of safe, routine anesthesia for the benefits of our patients. Since most anesthesia complications occur due to airway complications, airway management is therefore probably the most important aspect of safe anesthesia delivery. Capnography has the ability to detect critical respiratory problems, such as hypoventilation much ear-lier than pulse oximetry can, and allows in my opinion, the ability to diagnose and troubleshoot airway issues quicker and better than any other monitor available.

The Basics

Capnography, also referred to sometimes as end tidal CO2 or ETCO2 monitoring, allows one to measure the concen-tration of carbon dioxide (CO2) in a mixture of expired gases and it is expressed as the partial pressure of CO2. Capnometry and capnography are sometimes used syn-onymously as both analyze and record carbon dioxide, with the latter including a waveform. A “normal” capno-graph reading is the result of the integrated function of production of CO2 in the tissues, its carriage in the blood, exchange in the lungs and its exit through the airway space.

Normally, the ETCO2 is 2 to 5 mm Hg lower than arterial CO2 pressure. The typical range for end-tidal carbon dioxide during general anesthesia is 30 - 40 mm Hg. The capno-graph waveform (Figure No. 1) of the ETCO2 contains the expiratory portion (Phases I, II, II and occasionally IV) and the inspiratory portion (Phase 0). It also contains two angles, the alpha angle (α) between Phase II and III and

the beta angle (β) between Phase III and 0 which is also used to aide in the waveform interpretation.

Phase 0 is the inspiratory segment.

Phase I is the CO2-free gas that is not involved in the gas exchange (dead space).

Phase II is the rapid upswing and includes both alveolar gas and dead space gas.

Phase III is a plateau segment that involves alveolar gas and has a small positive slope. The ETCO2 is measured at the end of Phase III.

Phase IV (occasionally seen) is a terminal upswing present in patients with reduced chest compliance.

Alpha angle (α) is between Phases II and III is related to ventilation:perfusion matching of the lungs.

Beta angle (β) is between Phases III and 0 and is usually about 90°; it can be used to reassess rebreathing.

Uses And Applications

Anesthesia Delivery Machine or Apparatus:Abnormal capnography readings may indicate inadequate anesthetic delivery or faulty equipment. Capnography monitors may help adjust and calibrate fresh gas flows and detect circuit disconnects, leaks and one-way valve malfunctions and other device problems as well (see Fig-ure 1 – Capnograph B:3). Widening of the β angle with elevation of both Phases 0/I and III is a sign of the ma-chine’s inspiratory valve failure, while elevation of Phase 0/I and Phase III is a sign of expiratory valve failure or absorbent malfunction.

A)

B)

C)

D)

E)

F)

G)

AirwayThe capnograph was originally developed to aid in-tubation by confirming the proper positioning of the endotracheal tube since the presence of CO2 confirms tra-cheal intubation. If the tube is inadvertently positioned in the esophagus, or at any time gets displaced, the mon-itor will detect no CO2 and one can accurately know such event is happening. This still remains one of the most vital applications for anesthesia. Due to swallowed gas, esophageal intubation may result in CO2 return similar to that of the endotracheal intubation, except that the ETCO2 diminishes to zero within a few breaths (see Fig-ure 1 – Capnograph B:1). Even when used with laryngeal mask airways (LMA), it can help detect dislodgement, malpositioning or hypoventilation.

Breathing - VentilationEnd Tidal CO2 is a useful indication of how well the pa-tient is breathing. Abnormal readings may help detect distal airway obstructions, such as bronchospasm, and other breathing complications while patients are under sedation or general anesthesia (see Figure 1 – Capno-graph B:4&5). Carbon dioxide can be measured either at the breathing circuit (mainstream capnograph) or via as-piration of a gas sample by the capnograph (sidestream capnograph.) Sidetream capnograph may also be used on a nonintubated patient to give a qualitative assessment of respiration (see Figure 1 – Capnograph B:6). Airway obstructions will result in diminishing ETCO2 with altera-tions of the wave forms. These would return to normal once the obstruction is resolved.

CirculationAnother basic use of capnography is estimating cardiac output. It detects certain circulatory abnormalities. A sudden drop in the ETCO2 concentration may indicate a possible pulmonary embolism, shock or system leaks. Diminishing ETCO2 occurs with low perfusion, auto-PEEP (positive end expiratory pressure) or airway obstruction.

Malignant HyperthermiaA rapidly increasing ETCO2 value along with other signs is considered one of the first and most important warning signs of malignant hyperthermia, especially if it is unre-sponsive to hyperventilation.

HomeostasisCapnography can detect a variety of complications as-sociated with general anesthesia and sedation, including awareness, acid-base balance disorders and sepsis.

Neuromuscular FunctionIn anesthesia, the capnograph will change as the pa-tient’s neuromuscular function is altered (see Figure 1 – Capnograph B:2). If the muscle relaxant wears off during anesthesia, curare clefts will been seen as part of the waveform. Towards the end of the anesthetic, as the patient’s neuromuscular function returns to normal, the capnograph demonstrates the adequacy of spontaneous respirations by showing normal waves. In conjunction with other parameters, extubation of the patient is done when the capnograph returns to normal.

Non-Perioperative SituationsThere are instances in which practitioners outside of the OR or operatories use capnography to their advantage. In the ER and the ICU, tracheal intubation as a measure airway protection or for ventilation during transport of the critically ill patient, capnography is used. In addition, sleep studies use capnography to assist in assessing the degree of gravity of the apnea as well as the need for asleep ventilation requirements.

Conclusion

Although many of the parameters, applications and uses of capnography used today might not all be applicable to the dental setting, it is important to understand that this monitoring will allow one to become aware of many of the anesthetic problems quicker and with much more accuracy than any other monitor. This in turn will more likely direct the anesthesia provider to a specific action to correct such problem or concern. I have been using capnography now for over ten years, and I know my an-esthetic cases are less stressful and safer because of the greater airway monitoring capability that capnography provides. I would encourage consideration by those who administer any level of IV sedation to use capnography. Although capnography is not yet a standard of care in the sedated patient in the dental field, in my opinion, it should soon become the standard of care because of the wealth of information it provides.

Florida Dental Society of Anesthesiology P.O. Box 444,

Orange Park, FL 32073 904-703-4083

www.fdsahome.org