IS 2% LIDOCAINE WITH 1:50,000 EPINEPHRINE SAFE FOR ENDODONTIC SURGERY USE? J. A. Wallace 1 - C. Bissada 2 - O. Balytsky 3 - L. G. Schneider 4 - J. A. Magera 5 - T. G. Zullo 6 ABSTRACT Objective: To present forty one case studies utilizing 2% lidocaine with 1:50,000 epinephrine as the anesthetic of choice for endodontic surgery in relation to its cardiovascular and respiratory effects. Study Design: Endodontic surgical procedures were performed in forty-one patients, twenty-six American Society of Anesthesiologist Class I (ASA I and ASA II). -ASA I A normal healthy patient: no dental management alterations required. -ASA II A patient with mild systemic disease that does not interfere with day-to-day activity or that has a significant health risk factor. May or may not need dental management alterations. -ASA III A patient with moderate to severe systemic disease that is not incapacitating but that may alter day-to-day activity; may have significant drug concerns; may require special patient care; would generally require dental management alterations. Utilizing standard anesthesia techniques for endodontic surgery an average of two carpules of 2% lidocaine with 1:50,000 epinephrine per patient, blood pressure, pulse and respiration were recorded pre-injection, post-injection, and post-surgery. Results: There were no significant cardiovascular or respiratory changes from pre-injection baselines utilizing an analysis of variance. Conclusion: The use of 2% lidocaine with 1:50,000 epinephrine in these case studies demonstrated it could be utilized for endodontic surgery without fear of cardiovascular or respiratory effects thus we feel it is safe for endodontic surgery use in ASA I and ASA II patients. ASA III class patients require further case studies. 1- James A. Wallace, DDS, MDS, MSD, MS. Director, Endodontic Department 2- Christopher Bissada, DDS 3- Orest Balytsky, DMD 4- Lawrence G. Schneider, DDS. Associate Dean for Clinical Affairs 5- John A. Magera, DDS 6- Thomas G.Zullo, B.Ed., M.Ed., PhD Correspondence address: University of Pittsburgh School of Dental Medicine 3501 Terrace Street 3064 Salk Annex Pittsburgh, PA 15261-1923 29
Fig. 3: Entry into maxillary sinus and removal of overfill. Fig. 1: Utilizing surgical microscope. Fig. 4: Maxillary molar post-operative radiograph after removal of overfill. Our endodontic surgeries were performed in all areas of the mouth as illustrated further by the mandibular surgical procedure. (Fig. 5, 6, 7) Fig. 2: Maxillary molar surgical case presenting with symptomatic overfill. The purpose of these case studies was to evaluate the 2% lidocaine with 1:50,000 epinephrine as the anesthetic of choice in endodontic surgery in relation to cardiovascular and respiratory effects. Case studies were ASA I and ASA II patients. These case studies were performed utilizing the surgical microscope. (Fig.1) A typical maxillary case requiring a transantral approach to an overfill is presented. (Fig. 2, 3, 4) MATERIALS AND METHODS The endodontic surgery consisted of root end resection with a root end filling when indicated. The endodontic surgery also consisted of various teeth and flap designs with an average surgical time of one hour. All endodontic surgical procedures were performed on forty one patients (mean age 42) utilizing an average of two carpules of 2% lidocaine with 1:50,000 epinephrine (block and/or infiltration) preceded by topical lidocaine. We did not assess cardiovascular effects related to the amount of anesthesia injected because no significant effect was noted with the amount routinely given. Blood pressure, pulse and respiration were recorded pre-injection, post-injection and post-endodontic surgery. Twenty-six (26) patients were classified Type l ASA and fifteen (15) patients classified Type II ASA. The data were analyzed using analysis of variance procedures. 30
Fig. 5: Mandibular molar surgical case utilizing a submarginal incision. Fig. 6: Mandibular molar with bone removed from over root apices. post-injection and post-surgery records for systolic blood pressures. Systolic blood pressure for the ASA II group was virtually unchanged throughout the study while the ASA I patients exhibited a slight (but not significant) increase from pre to post-injection. (Table I-A) There were no significant differences between the ASA I and ASA II patients for diastolic pressure (F=0.09;p=0.77) and the magnitude of the mean value was similar for the two groups. Diastolic blood pressure did change as related to the injection of lidocaine irrespective of ASA group. There was a decrease following injection (pre to post-injection) followed by a return to near pre-injection levels after endodontic surgery was completed for both the ASA I and ASA II patients (F=5.60;p=0.005). (Table 1-B) Both rate pressure produce (RPP, heart rate x systolic blood pressure) and pulse exhibited similar patterns of response. Again, there were no statistically significant differences between ASA I and ASA II groups for either measure. RPP and pulse increased significantly following the lidocaine injection and then returned to near pre-injection levels (F=7.87;p=0.0001 and F=11.77;-0.0001, respectively). ASA I patients exhibited a larger magnitude of change than did the ASA II s. RPP increased nearly 1400 points from pre to postinjection for the ASA I group compared to 600 points for the ASA II group. Pulse rate increased approximately 8.5 beats per minute from pre to post-injection for ASA I patients and 4.5 beats for the ASA II patients. However, as noted, these differences between ASA groups did not reach a level of statistical significance for either RPP or pulse rate. Only respiration exhibited a statistically significant interaction effect. While respiration remained fairly constant throughout the duration of the study for the ASA I patients, ASA II s showed progressive, but negligible decrease from pre-injection to post-surgery. DISCUSSION Fig. 7: Mandibular molar with root-ends resected and gutta percha examined. RESULTS Although the mean value for both systolic blood pressures was higher for the ASA II patients, it was higher for ASA II versus ASA I patients throughout the course of the study but was not statistically significant. Also, there were no significant differences among the three recordings of pre-injection, For surgery, 2% lidocaine with 1:50,000 epinephrine as a local anesthetic agent was used for efficacy and hemostatic action and administered via infiltration or regional block. There is a question as to the safety of the 1:50,000 concentration of epinephrine related to adverse cardiovascular effects after systemic absorption. Factors other than the anesthetic that may account for such a hyperdynamic cardiovascular response include fear, pain from the injection, stress, intravascular injection, drug interaction or pain from the procedure. Previous reports have shown that the amount of epinephrine added to local anesthetics is negligible compared to the amount of endogenous epinephrine released in response to stress. 31
B Mean C Mean S Y S T O L I C P R E S S U R E ASA1 121.62(17.67) 125.11(18.65) 120.12(15.13) 122.28(17.12) ASA2 132.13(23.37) 131.80(23.32) 133.33(23.29) 132.42(22.80) AMean ASA 125.46(20.31) 127.56(20.45) 124.95(19.35) 126.0(19.91) D I A S T O L I C P R E S S U R E ASA1 77.19(10.03) 74.23(11.46) 76.31(9.15) 75.91(10.20) ASA2 77.13(9.45) 73.33(9.35) 79.33(13.52) 76.80(11.04) ASA 77.17(9.70) 73.90(10.62) 77.63(10.93) 76.24(10.48) R A T E P R E S S U R E P R O D U C T ASA1 8764.35(1992.30) 10157.50(2546.08) 8854.39(1504.58) 9258.74(2130.47) ASA2 9479.27(3461.64) 10086.47(3468.77) 9581.00(2736.95) 9715.58(3177.55) ASA 9025.90(2606.98) 10131.52(2874.73) 9120.22(2040.15) 9426(2560) P U L S E R A T E ASA1 72.15(13.23) 80.69(13.17) 73.69(10.57) 75.51(12.19) ASA2 70.73(17.47) 75.33(16.65) 71.47(14.15) 72.51(15.91) DMean ASA 71.63(14.72) 78.73(14.57) 72.88(10.62) 74.41(13.68) E R E S P I R A T I O N ASA1 12.88(2.08) 12.88(1.84) 13.00(2.14) 12.92(1.99) ASA2 12.60(1.40) 11.93(0.46) 11.80(0.41) 12.11(0.93) Mean ASA 12.78(1.85) 12.54(1.55) 12.56(1.80) 12.63(1.729) TABLE I - Mean and (Standard Deviations) for Variables used in the study. Our case studies combining data from ASA I and ASA II patients utilizing an average of two (2) carpules of 2% lidocaine with 1:50,000 epinephrine, showed no statistically significant change in the systolic blood pressure although there is about an eight fold increase in plasma epinephrine over baseline in the literature. We demonstrated a statically significant decrease in diastolic blood pressure as would be expected with this level of plasma ep nephrine related to its Beta-2 activity on skeletal muscle arterioles irrespective of ASA Group. The plasma epinephrine level related to its Beta 1 activity on the heart produced a statistically significant increase in pulse rate (about a 10% increase) not even approaching tachycardia (100 BPM) and returning to pre-existing levels postsurgery for both ASA groups which is a level that has very little effect on heart. 32
The RPP, a measurement of cardiac work related to the myocardial oxygen consumption, demonstrated a statistical significance. However, this increase was only 12%, not a clinically significant effect on the heart of ASA I and ASA II patients. The RPP at a B.P of 120/80 and pulse of 72 is 8,640. Myocardial ischemia rarely occurs at a RPP<12,000. Heart rate plays a greater role in myocardial oxygen demand than does systolic blood pressure, therefore, ischemia was not significant because pulse rate increase was insignificant clinically. The maximum change for respiration rate was only 0.80% between pre-injection and post-surgery (12.6 to 11.8) for the ASA II patients, and thus was not a factor. Future studies will evaluate the electrocardiographic response to 2% lidocaine with 1:50,000 epinephrine in relation to cardiac arrhythmias and the ST segment of the electrocardiogram, which is an indicator of myocardial ischemia. Utilizing these parameters we need to study 2% lidocaine 1:50,000 epinephrine and endodontic therapy on ASA III patients along with drug interactions on ASA I, II and III classes of patients. CONCLUSION These case histories findings in conjunction with others show that 2% lidocaine with 1:50,000 epinephrine causes no appreciable cardiovascular changes. However, systolic blood pressure is raised insignificantly and diastolic blood pressure lowered with both returning to pre-existing levels postsurgery. Heart rate is increased 10%, which does not begin to approach tachycardia and thus is not significant clinically. Respiration as an indicator of stress remained constant throughout the study thus an indicator stress was not at a level to effect cardiovascular changes. These case studies demonstrate that 2% lidocaine with 1:50,000 epinephrine produces clinically insignificant effects on cardiovascular and respiratory function as used clinically in endodontic surgery. REFERENCES 1. Chernon B, Balesteri F, Ferguson CD, Terezhalmy GT, Fletcher JR, Lake R. Local Dental Anesthesia with Epinephrine Arch Intern Med- Vol, Nov. 1983, 2141-2143 2. Towles JA, Liebow C, Effects of Exogenous and Endogenous Epinephrine on Local Anesthesia. Periodontal Insights Oct. 1995 9-11. 3. Knoll-Kohler E, Lewitzki O. Cardiohemodynamic and plasma level responses to intraoral submucosal injection of adrenaline, J Dent 1991;19:236-240. 4. Knoll-Kohler E, Frie A, Becker J, Ohlendord D. Changes in Plasma Epinephrine Concentration after Dental Infiltration Anesthesia with Different Doses of Epinephrine. J Dent Res June, 1989, 1098-1101. 5. Davenport, RE, Parcelli RJ, Iacono VJ, Bonura CF, Mallis GI and Baer PN. Effects of Anesthetics containing Epinephrine on Catecholamine Levels during Surgery. J. Periodontal 1990;61:553-558. New Book Preface from the authors A few decades ago, the pioneers of endodontics had to take immense measures to promote the image and importance of endodontics. As a result, presently the general public has become aware of the possibility and also the importance of saving teeth and has started demanding for endodontic treatment from the general dentist. Such a demand has started levying a strain on many general dentists who had not had adequate training in endodontics during their under-graduate training period. Continual advancements in biologic and technologic knowledge further add to the strain. There is an urgent need to promote and upgrade the knowledge and the advancement in endodontics amongst the general dentists. The Current concepts in endodontics is designed primarily towards this goal. The style and contents of this book have been planned so as to bring to light in a simple way the current development in the concepts and techniques. Moreover the keen reader will find sufficient material to stimulate his own thought. It is hoped that this book would indeed be of benefit for the general dentists, and thereby for the patients whom they treat. Authors 33