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J Oral Maxillofac Surg61:1249-1252, 2003

Sevoflurane General Anesthesia: AnAlternative Technique in the PediatricOral and Maxillofacial Surgery Patient

Mason Lee, DDS, MD,* Henry E. Bennett, DDS,†

and Newton Gordon, DDS, MS‡

Purpose: The objective of this prospective descriptive study was to report our experience with analternative general anesthetic technique, using sevoflurane for the pediatric patient, in an ambulatorysetting.

Patients and Methods: Twenty consecutive pediatric patients participated over a 4-month period. Ageneral anesthetic technique, using mask induction with sevoflurane and maintenance with a nasaltrumpet as airway, was used throughout the surgical procedure. A standard anesthesia and recoveryrecord was made for each patient; this included observations for untoward effects and complications.

Results: The average time for induction of anesthesia was 95 seconds, time from termination ofsevoflurane to eye opening was 8 minutes, and duration of recovery was 30 minutes. Procedure time foreach case did not exceed 10 minutes. Two patients had transient tachycardia.

Conclusions: The results of this prospective descriptive study indicate that this technique is aneffective and acceptable alternative to other modalities for the control of apprehension and fear in thepediatric patient in an ambulatory oral and maxillofacial facility.© 2003 American Association of Oral and Maxillofacial SurgeonsJ Oral Maxillofac Surg 61:1249-1252, 2003

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evoflurane, a potent rapid onset and recovery inha-ational anesthetic agent, was used successfully inapan for many years, before Food and Drug Admin-stration approval for use in the United States. Therere numerous publications over the past decade de-cribing the safety and efficacy of sevoflurane (Ultane;bbott Laboratories, North Chicago, IL) as a generalnesthetic in the adult and pediatric population.

The traditional method for obtaining intravenousccess before induction is not a viable option for

*Chief Resident, Department of Oral and Maxillofacial Surgery,

niversity of California San Francisco, San Francisco, CA.

†Associate Clinical Professor, Department of Oral and Maxillo-

acial Surgery, University of California San Francisco, San Francisco,

A.

‡Clinical Professor, Department of Oral and Maxillofacial Sur-

ery, University of California San Francisco; Chief, Dentistry/Oral

nd Maxillofacial Surgery Service, San Francisco General Hospital,

an Francisco, CA.

Address correspondence and reprints requests to Dr Gordon:

an Francisco General Hospital, Department of Oral and Maxillofa-

ial Surgery, 1001 Potrero Ave, 1N1, San Francisco, CA 94110;

-mail: newtong@itsa.ucsf.edu

2003 American Association of Oral and Maxillofacial Surgeons

278-2391/03/6111-0003$30.00/0

toi:10.1016/S0278-2391(03)00723-7

1249

any pediatric patients in the oral and maxillofacialurgery clinical setting. Given their uncooperativeehavior and the difficulty this creates in achieving

ntravenous access, administration of a potent inhala-ion anesthetic agent facilitates induction of generalnesthesia without the need to obtain intravenousccess. The purpose of this prospective descriptivetudy is to present an acceptable and effective tech-ique for administering outpatient sevoflurane anes-hesia without preoperative sedatives in pediatric pa-ients at a large urban public hospital.

atients and Methods

The sample consisted of 20 pediatric patients at Sanrancisco General Hospital (age range, 5 to 14 years;ean age, 8.5 years). All patients were very appre-ensive and uncooperative; some were mentally chal-

enged. The study period was 4 months (March 2001hrough June 2001), or one chief resident’s rotation.he procedures were supervised by one attendingurgeon (H.E.B.).

All patients were scheduled for minor dentoalveo-ar procedures under this alternative technique withevoflurane as the sole anesthetic agent. Parents werenformed of the risks, benefits, and alternatives toevoflurane general anesthesia, and consent was ob-

ained. The alternatives were local anesthesia and oral

sedation; local anesthesia, oral sedation, and nitrousoxide; local anesthesia and intramuscular sedation, orlocal anesthesia and intravenous sedation. The par-ents were given preoperative instructions, includingnothing by mouth for 6 hours before surgery, withexception of clear liquids up to 2 hours before theprocedure.1 The patients were then referred to thePediatric Clinic for a history and physical examina-tion, including urine analysis and hematocrit. On theday of surgery, compliance with nothing-by-mouthinstructions was confirmed. A brief review of thepatient’s medical history and an assessment of weightand temperature were conducted. The followingmonitors were attached: blood pressure (HewlettPackard Anesthesia M1092AA; Hewlett-Packard, An-dover, MA), heart rate with graphic electrocardio-graphic tracing (Hewlett-Packard ECG M1001B, NBPM1008B, SpO2/PLETH M1020A, REC M1116B), pulseoximeter (Nellcor N-395; Nellcor, Pleasanton, CA),capnograph (Hewlett-Packard), sevoflurane gas spec-trometry (Ohmeda 5250 RGM; Ohmeda, Louisville,CO), and precordial stethoscope.

Mask inhalation with 8% sevoflurane2-4 at a gas flowrate of at least 3 L oxygen/min was then administeredvia an Ohmeda anesthesia unit, until loss of lid reflex.A nasal trumpet, lubricated with 5% lidocaine oint-ment and attached to a 60° angled connector (Fig 1),was then inserted through the left or right nostril. Thecontralateral nostril was occluded with 2 � 2 gauze,and the posterior pharynx was packed with 4 � 4gauze, resulting in a semiclosed system (Fig 2). Afterinfiltration or block with local anesthetic (2% lido-caine with 1:100,000 epinephrine, �4.4 mg/kg), thesevoflurane vaporizer was adjusted to 2.5% and theoxygen flow was maintained at 3 L/min, maintaininga minimum alveolar concentration of 1.5. The den-toalveolar procedure was then completed. Dentoalve-olar procedures included incision and drainage ofvestibular and buccal space abscesses, single and mul-tiple tooth extractions, and incisional/excisional biop-sies.

At the completion of the procedure, sevofluranewas discontinued, and 100% oxygen, at a rate of 3 to4 L/min to maintain the oxygen saturation at greaterthan 98%, was administered until there was eye open-ing and response to physical stimuli. Only after eye

opening and a response to physical stimuli was thenasal trumpet assembly removed in the operatingroom.

Patients were transferred to the adjacent recoveryroom, where they were monitored by a registerednurse. Parameters monitored were oxygenation(pulse oximetry), ventilation (breathing frequency,airway patency) and circulation (blood pressure,pulse), pain level, and bleeding/secretions. Supple-mental oxygen was administered as needed and tol-erated. Patients were discharged in the company of aparent or guardian when the vital signs were stablefor at least 10 minutes, the pain and bleeding werecontrolled, and the Aldrette score was 10 (maximum,10).5

Results

There were no signs or symptoms of breath-hold-ing, laryngospasm, or airway irritability on mask in-duction. Transient tachycardia was noted in 2 patientsbut resolved after decreasing the sevoflurane from 8%to 3%. Although the concentration of sevoflurane washigh (8%) for induction, there were no signs or symp-toms of stage II excitation in any of our 20 patients.The average time for induction of anesthesia was 95seconds. The dentoalveolar procedures for each pa-tient lasted no longer than 10 minutes. The averagetime from termination of sevoflurane to eye opening

FIGURE 2. Nasal airway and oral pack and mouth prop in place.

FIGURE 1. Nasal trumpet with angled connector.

1250 PEDIATRIC SEVOFLURANE ANESTHESIA TECHNIQUE

was 8 minutes; the average duration of recovery was30 minutes.

Discussion

Successful outpatient anesthetic management ofthe pediatric patients with agents such as oral orintramuscular benzodiazepine and ketamine, inhalednitrous oxide and oxygen, and local anesthetic hasbeen the mainstay of many oral and maxillofacialsurgery practices. For the fearful, anxiety-ridden, andneedle-phobic child, halothane has been the agent ofchoice for children, due to its odorless, nonpungent,and rapid-onset properties. However, sensitization ofthe myocardium to epinephrine and the subsequentdevelopment of ventricular arrhythmias, cardiac de-pression, and possible hepatic necrosis have led tothe search for a superior inhaled agent for children.The properties of sevoflurane make it an acceptablealternative.

Abbott Laboratories initially synthesized sevoflu-rane in 1968. Although it was reported in the litera-ture in 1971, research and development were delayedbecause of the preeminence in the marketplace ofisoflurane, a pungent halogenated agent with rapidemergence.3,6 Abbott Laboratories sold the rights forsevoflurane to Maruishi Pharmaceutical Co, Ltd,Osaka, Japan. Maruishi pursued the research and de-velopment of sevoflurane, which led to its eventualuse in Japan in 1990.

Studies1,2,4,6-12 have shown that sevoflurane has sev-eral advantages over halothane, when administered tochildren for brief surgical procedures. These advan-tages include decreased ventricular arrhythmias,6,13,14

decreased episodes of breath-holding and laryngo-spasms, faster onset and recovery from anesthesia,11

and generally improved overall patient acceptance.Additional advantages of sevoflurane include ease ofadministration, allayment of patient fears, and facilita-tion of placement of an intravenous line without pa-tient movement.

In our technique, we used high (8%) concentrationof sevoflurane instead of the usual incremental in-creases made with other agents for induction. Thisresulted in rapid inductions. We have found that un-like halothane, desflurane, and isoflurane, sevofluraneis well tolerated in high concentrations. In a prospec-tive, randomized, double-blind study of 46 pediatricpatients, it was confirmed that 8% sevoflurane withnitrous oxide, compared with incremental increasesof halothane and sevoflurane, had a faster inductiontime and decreased the incidence of coughing andbreath-holding.3 In our series, there was no incidenceof breath-holding or laryngospasm on induction.

In a prospective, randomized, double-blinded, con-trolled clinical study of 80 children undergoing dental

extractions, Ariffin et al11 showed that time for loss ofeyelid reflex was more rapid with sevoflurane (89seconds) than for halothane (127 seconds). The lowblood/gas partition coefficient of 0.68 for sevofluraneaccounts for its rapid induction and recovery charac-teristics.

Also, Paris et al,6 in a prospective, randomized,double-blinded clinical study of 100 children, age 2 to12 years, showed that the incidence of cardiac ar-rhythmias during induction, surgery, and recoverywas greater with halothane (62%) than with sevoflu-rane (28%). The arrhythmias seen with halothanewere more often ventricular in origin compared withthe supraventricular arrhythmias seen with sevoflu-rane.

Ganzberg et al15 described an additional techniqueof administering sevoflurane using a nasal hood toachieve sedation for third molar extractions. Theystated that one of the difficulties encountered waslightening of sedation after the mouth was proppedopen, resulting in the escape of sevoflurane. With thetechnique described in our cases, the posterior phar-ynx and contralateral nostril were occluded withgauze (Fig 3), thereby allowing for a semiclosed cir-cuit and no lightening of anesthesia.

We have also used the laryngeal mask airway as analternative to the nasal trumpet airway to administersevoflurane. The laryngeal mask airway has the idealairway characteristics, which include closed circuit,protection from aspiration of oral secretions and de-bris, minimal interference of the surgical field, andlow complication rate.16

Some of the disadvantages of our technique includeadditional equipment such as a special sevoflurane

FIGURE 3. Schematic of airway maintenance.

LEE, BENNETT, AND GORDON 1251

vaporizer and subsequent expense, increased risks ofmalignant hyperthermia,17 renal toxicity secondary tocompound A and fluoride ions, and the acquisition offamiliarity with the properties and characteristics ofthis new inhaled agent.

Compound A, a vinyl ether, is the result of meta-bolic degradation of sevoflurane in the presence ofcarbon dioxide absorbents (soda lime, baralyme) inthe anesthesia circuit. Studies18,19 have shown thatcompound A can cause renal tubular toxicity in rats atlevels greater than 50 to 100 ppm. Correlations havebeen made, with higher compound A levels beingobserved when the temperature of the soda limebeads increased to 40.0°C and the gas flows were lessthan 2 L/min. In a prospective clinical study, Frink etal20 observed and analyzed 19 children, aged 3months to 7 years, undergoing sevoflurane anesthesiafor a mean duration of 240 minutes for various surgi-cal procedures. Compound A levels were measured inboth the inspiratory and expiratory circuits, and thetemperature levels of the carbon dioxide absorbentswere recorded during the preoperative, intraopera-tive, and postoperative periods. Also, renal functionwas assessed with serial blood specimens for creati-nine and blood urea nitrogen. Despite the finding ofcompound A levels of 15 ppm, there was no increasein creatinine or blood urea nitrogen and no change inrenal function. These findings have led to the sugges-tion that compound A may be a theoretical risk ratherthan a true risk in humans. Consequently, more hu-man studies are needed to determine the true risk ofcompound A.

Fluoride-induced nephrotoxicity (polyurea, hyper-natremia, hyperosmolarity, inability to concentrateurine) is attributed to metabolism of fluorinated vola-tile anesthetics. Plasma fluoride ion levels higher than50 �mol/L have been measured in patients anesthe-tized with sevoflurane and enflurane. However, theabsence of clinically significant renal dysfunctionwould implicate factors other than peak levels offluoride ions.21 This would be consistent with theobservation that occasional patients with increasedplasma concentration of fluoride ion after the admin-istration of sevoflurane experience less renal dysfunc-tion than do patients receiving enflurane and mani-festing lower plasma fluoride concentrations. Thismay be attributed to intrarenal production of fluorideions by enflurane, in contrast to hepatic productionby sevoflurane.22,23

It might be claimed that this technique is not usefulin the ambulatory oral and maxillofacial surgery set-ting given its initial high startup costs and additionaltraining requirements. However, inhaled sevofluraneis an excellent anesthetic in the outpatient setting,when treatment options for the difficult and needle-

phobic child are considered. This alternative tech-nique for general anesthesia in our pediatric popula-tion was effective and well tolerated.

References1. Schreiner M, Triebwasser T, Keon T: Ingestion of liquids com-

pared with preoperative fasting in the pediatric outpatients.Anesthesiology 72:593, 1990

2. Sigston PE, Jenkins AM, Jackson EA, et al: Rapid inhalationinduction in children: 8% Sevoflurane compared with 5% halo-thane. Br J Anaesth 78:362, 1997

3. Baum VC, Yemen TA, Baum LD: Immediate 8% sevofluraneinduction in children: A comparison with incremental sevoflu-rane and incremental halothane. Anesth Analg 85:313, 1997

4. Agnor R, Sikisch N, Lerman J: Single breath vital capacity rapidinhalation induction in children. 8% Sevoflurane versus 5%halothane. Anesthesiology 89:379, 1998

5. Aldrete JA: The post anesthesia recovery score revisited. J ClinAnesth 7:89, 1995

6. Paris ST, Cafferkey M, Tarling M, et al: Comparison of sevoflu-rane and halothane for outpatient dental anaesthesia in chil-dren. Br J Anaesth 79:280, 1997

7. Brown B: Sevoflurane: Introduction and overview. AnesthAnalg 81:S1, 1995

8. Smith I, White PF: Sevoflurane—a long awaited volatile anaes-thetic. Br J Anaesth 76:435, 1996

9. Haraguchi N, Furusada H, Takezaki R, et al: Inhalation sedationwith sevoflurane: A comparative study with nitrous oxide.J Oral Maxillofac Surg 53:24, 1995

10. Hatch DJ: New inhalation agents in paediatric anesthesia. Br JAnaesth 83:42, 1999

11. Ariffin SA, Whyte JA, Malins AF, et al: Comparison of inductionand recovery between sevoflurane and halothane supplemen-tation of anaesthesia in children undergoing outpatient dentalextractions. Br J Anaesth 78:157, 1997

12. Lerman J: Sevoflurane in pediatric anesthesia. Anesth Analg81:s4, 1995

13. Blayney MR, Malins AF, Copper GM: Cardiac arrhythmias inchildren during outpatient general anaesthesia for dentistry: Aprospective randomized trial. Lancet 354:1864, 1999

14. Navarro R, Weiskopf RB, Moore MA, et al: Humans anesthe-tized with sevoflurane or isoflurane have similar arrhythmicresponse to epinephrine. Anesthesiology 80:545, 1994

15. Ganzberg S, Weaver J, Beck M, et al: Use of sevoflurane inha-lation sedation for outpatient third molar surgery. Anesth Prog46:21, 1999

16. Brimacombe BJ: The laryngeal mask airway for dental sur-gery—review. Austral Dent J 40:10, 1995

17. Ducart A, Adnet P, Renaud B, et al: Malignant hyperthermiaduring sevoflurane administration. Anesth Analg 80:609, 1995

18. Gonsowski C, Laster M, Eger EI II, et al: Toxicity of compoundA in rats: Effects of a 3-hour administration. Anesthesiology80:556, 1994

19. Callan C, Prokocimer P, Delgado-Herrera L, et al: Effects ofcompound A on the kidney of Sprague-Dawley rats. Anesthe-siology 81:A1284, 1994

20. Frink EJ, Green WB, Brown EA, et al: Compound A concentra-tions during sevoflurane anesthesia in children. Anesthesiology84:566, 1996

21. Frink EJ, Ghantous M, Malan TP, et al: Plasma inorganic fluoridewith sevoflurane anesthesia: Correlation with indices of he-patic and renal function. Anesth Analg 74:231, 1992

22. Kharasch ED, Hankins DC, Thummel KE: Human kidney me-thoxyflurane and sevoflurane metabolism: Intrarenal fluorideproduction as a possible mechanism of methoxyflurane neph-rotoxicity. Anesthesiology 82:689, 1995

23. Frink EJ, Malan TP, Isner RJ, et al: Renal concentrating functionwith prolonged sevoflurane or enflurane anesthesia in volun-teers. Anesthesiology 80:1019, 1994

1252 PEDIATRIC SEVOFLURANE ANESTHESIA TECHNIQUE