Peter-John Wormald, M.D., Theodore Athanasiadis, M.B.B.S., Guy Rees, F.R.C.S., F.R.A.C.S., and Simon Robinson, F.R.A.C.S.

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1 An Evaluation of Effect of Pterygopalatine Fossa Injection with Local Anesthetic and Adrenalin in the Control of Nasal Bleeding during Endoscopic Sinus Surgery Peter-John Wormald, M.D., Theodore Athanasiadis, M.B.B.S., Guy Rees, F.R.C.S., F.R.A.C.S., and Simon Robinson, F.R.A.C.S. (Australia) ABSTRACT Background: The aim of this study was to determine the effect of pterygopalatine fossa infiltration with lidocaine and adrenalin on bleeding in the surgical field during endoscopic sinus surgery. Methods: A prospective blind randomized controlled trial was performed. Fifty-five patients were randomized to receive a unilateral transoral infiltration of the pterygopalatine fossa with 2 ml of 2% lidocaine and 1:80,000 adrenalin. The operating surgeon was blinded as to which side had been infiltrated at the start of surgery. The surgical field was graded on a previously validated surgical field grading scale every 15 From the Department of Surgery Otolaryngology Head and Neck Surgery, Adelaide and Flinders Universities, South Australia, Australia There are no conflicts of interest Address correspondence and reprint requests to Peter-John Wormald, M.D., Department of Surgery Otolaryngology Head and Neck Surgery, Queen Elizabeth Hospital, Woodville South, 5011, South Australia, Australia Copyright 2005, OceanSide Publications, Inc., U.S.A. minutes with the side being operated on alternated every 30 minutes. The pulse, mean arterial blood pressure, and endtidal CO 2 concentration were monitored with each surgical field observation. Results: At each individual time point from 30 minutes to 3.5 hours there was a significant difference in surgical grade between injected and noninjected sides in favor of the injected side (p 0.01). The difference between surgical grades averaged across all time points was slight but significant. The injected side had an overall mean of 2.59 (SE, 0.22) compared with 2.99 (SE, 0.23) for the noninjected side. Heart rate also was found to correlate independently to surgical grade. Conclusion: Injection of the pterygopalatine fossa resulted in an improved surgical field during endoscopic sinus surgery. (American Journal of Rhinology 19, , 2005) Endoscopic sinus surgery (ESS) is conducted in the very narrow confines of the middle meatus, frontal recess, and posterior ethmoids. Even a small amount of bleeding can obscure the surgical field. Regular contamination of the end of the endoscope can be frustrating for the surgeon and this can lead to surgical maneuvers being performed without clear visualization. This increases the risk of complications as the procedures are performed blind. Various techniques 288 May June 2005, Vol. 19, No. 3

2 have been developed and described by surgeons attempting to minimize bleeding during ESS. These include preoperative nasal decongestion with oxymetazaline, cocaine, and topical adrenalin. 1,2 Infiltration of the lateral nasal wall with lidocaine and 1:80,000 adrenaline also is commonly used. Varying the technique of general anesthesia and the use of hypotensive agents such as -blockers or sodium nitroprusside also have been used with some success. 3 7 However, despite these techniques, excessive bleeding remains a problem in the practice of ESS. The main blood supply of the nasal cavity is via the terminal branches of the maxillary artery. This artery enters the pterygopalatine fossa and divides into five branches (descending pharyngeal artery, greater and lesser palatine arteries, sphenopalatine artery, and the artery of pterygoid canal), which supply the nasal cavity. This fossa can be accessed via the greater palatine foramen. 8 Injection into the palate with 2% lidocaine and 1:80,000 adrenalin has been shown to significantly reduce blood supply to the pulpal area of the palate. 9 Although the main aim of infiltration was to induce local vasoconstriction, injection of adrenalin alone produces hyperalgesia, in the presence of tissue injury. 10 If pain receptive C-fibers are sensitized, noradrenaline is capable of further sensitization, mediated via -2-adrenoreceptors. 11 In addition, adrenalin increases tissue cyclic adenosine monophosphate, which with local ischemia allows accumulation of proalgesic mediator substances in the surgical field, facilitating nociception. 12 With the combination of adrenalin and lignocaine the postinfiltration blood flow is reduced by up to 50% of baseline. 13 The aim of this study was to assess the effect of pterygopalatine fossa injection with local anesthetic and adrenalin on the surgical field in this form of surgery. PATIENTS AND METHODS Inclusion and Exclusion Criteria Approval was obtained from the Adelaide group of the teaching hospital ethics committee. All patients over the age of 18 years undergoing ESS for chronic sinusitis at these hospitals were invited to participate. The study was conducted from January 1999 to July Patients were excluded from the study if they had hypertension, a hypersensitivity to lidocaine hydrochloride, or were on anticoagulation therapy. The computed tomography scan was reviewed and patients with asymmetrical disease were excluded. Patients were able to withdraw from the study at any stage without it affecting their medical care. Study Design A prospective randomized double-blind controlled trial was conducted. A power study was performed with a power of 80% and a clinically significant difference in bleeding between the sides of 15% (SD, 15%) with a significance level of 5% (p 0.05). The power study suggested that if each patient was used as their own control, 50 patients were required for the study. Computer-generated randomization was used to determine on which side the patient would receive their pterygopalatine fossa injection and which side of the nose would be operated on first. The surgeon performing the ESS and evaluating the bleeding was not present at the time of injection. A total of 55 patients were enrolled in the study (24 women and 31 men) with a median age of 50 years (range, years). Operative Technique After oral intubation, vital signs and all anesthetic parameters were kept as constant as possible for the duration of the surgery. Three cotton neuropatties were soaked with 1 ml of 10% cocaine and 1 ml of 1:1000 adrenalin and 2 ml of saline. One neuropattie was placed in the sphenoethmoidal recess, one was placed in the middle meatus, and one was placed in the anterior end of the middle turbinates on each side of the nose for 3 minutes. The region of the agger nasi cell and the middle turbinate were injected bilaterally with 0.5 ml of 2% lidocaine hydrochloride with1:80,000 adrenalin. The pterygopalatine infiltration was performed using the technique described by Mercuri. 14 This involved introducing a needle into the greater palatine foramen and traversing the greater palatine canal into the pterygopalatine fossa. A dental syringe with the standard 25-gauge dental needle was used. The needle was bent at mm and inserted into the greater palatine canal until the bend. The average length of the greater palatine canal is 10 mm and the bending of the needle limited penetration of the needle into the pterygopalatine fossa and consequently lessened potential complications. 14 The greater palatine foramen is located by placing a finger in the mouth and palpating the junction of the hard and soft palate. The finger is drawn anterior to the posterior rim of the hard palate for 3 5 mm until the foramen is felt. An endoscope then is placed alongside the finger and the position of the finger is viewed as the finger is withdrawn. Keeping the region of the foramen in view, the needle is passed into the foramen until the bend in the needle is reached. After aspiration, 2 ml of local anesthetic (lidocaine 2% with 1:80,000 adrenalin) is slowly injected. The palate is seen to blanch. At the commencement of surgery and at regular 15- minute intervals the anesthetist prompted the surgeon for a surgical field assessment. The side being operated on was alternated every 30 minutes. The extent of nasal bleeding was evaluated according to the validated scale used by Boezaart and van der Merwe 4 (Table I). At each assessment other parameters including mean arterial blood pressure (MAP), heart rate, concentration of end-tidal CO 2, and the isoflurane concentration were recorded by the anesthetist. Statistical Analysis Analysis of the data was performed by an independent statistician provided by BiometricsSA. All analyses were performed with linear mixed modeling using restricted American Journal of Rhinology 289

3 Grade TABLE I Endoscopic Grading of Nasal Bleeding 4 Assessment 0 No bleeding (cadaveric conditions) 1 Slight bleeding no suctioning required 2 Slight bleeding occasional suctioning required 3 Slight bleeding frequent suctioning required; bleeding threatens surgical field a few seconds after suction is removed 4 Moderate bleeding frequent suctioning required and bleeding threatens surgical field directly after suction is removed 5 Severe bleeding constant suctioning required; bleeding appears faster than it can be removed by suction; surgical filed severely threatened and surgery usually is not possible maximum likelihood to estimate the model. This allows analysis of an unbalanced data set with procedures ending at different times as well as stratification of residual errors into subject variation and subject by time variation. As restricted maximum likelihood assumes normally distributed residuals, the surgical grade frequency distribution was converted to a z score. The z score, its mean, and SD then were transformed back on the original scale, thus approximating a normal distribution. Statistical significance was set at p RESULTS Patients and Methods Atotal of 55 patients were entered into the study, 27 of which had primary operations and 28 who had revision operations. The most common diagnosis was chronic sinusitis (n 25) and nasal polyposis (n 23) with 7 patients having allergic fungal sinusitis. The median surgical time was 120 minutes (range, minutes). Because each patient served as their own control, blood pressure, pulse rate, and expiratory CO 2 levels were not considered to influence surgical bleeding between injected and noninjected sides (Table II). Surgical Grade A comparison of endoscopic surgical field grade between injected and noninjected sides showed a statistically significant benefit (p 0.01) in favor of the injected side throughout the time course of the study, which was up to 3.5 hours. The injected side had an overall mean of 2.59 (SE, 0.22) compared with 2.99 (SE, 0.23) for the noninjected side (Table II). There was a significant correlation between heart rate (HR) and surgical grade (p 0.004). This was true at all time points (except after 3 hours where limited data restricted analysis), r (Fig. 1). This correlation was independent of time, the effect of pterygopalatine fossa injection, or the possible interaction between treatment and time. MAP did not significantly alter surgical grade at any time point or on average across all time points (p 0.724). However, there was a significant correlation between surgical grade and time, with a gradually worsening mean grade as the procedure progressed (p ). Importantly, there were no adverse events, specifically no neurological side-effects were recorded either intraoperatively or postoperatively because of the pterygopalatine fossa injection. DISCUSSION This study has shown that at all time points there was a statistically significant difference in surgical field between the injected and noninjected sides in favor of the injected side. This effect was independent of the side injected and a variety of other variables including HR and MAP. TABLE II Mean Values of Surgical Grade and Measured Variables by Treatment Group Injection (SE) Noninjection (Standard Error) P Value Surgical grade 2.59 (0.22) 2.99 (0.23) P 0.019* Heart rate 70.2 (1.7) 73.1 (1.7) P 0.09 MAP 67.1 (1.3) 67.6 (0.94) P CO 2 concentration 32.5 (1.5) 32.5 (1.7) P 0.59 *Statistically significant (p 0.05). 290 May June 2005, Vol. 19, No. 3

4 Figure 1. Boxplot of heart rate versus surgical grade. Bleeding in the surgical field is related to a number of factors. The most important of these are the severity of disease present, as some conditions such as allergic fungal sinusitis have a higher degree of vascularity than other diseases. 15 Other factors include patient comorbidity such as uncontrolled hypertension and coagulation disorders. 12 Deterioration in surgical field quality because of bleeding has been shown to lengthen the procedure and may increase the risk of operative complications. 16 The inability of the surgeon to visualize adequately the surgical field also contributes to increased tissue trauma with an increased likelihood of postoperative scarring, adhesions, and recurrence of disease. 15,17 ESS was performed on a patient group in whom 45% had chronic rhinosinusitis, 25% had nasal polyposis, 16% had both chronic rhinosinusitis and nasal polyposis, and 12% had allergic fungal sinusitis. This is felt to be a reasonable sample of the patient group and is similar to previous epidemiological studies conducted in our department. 18 Slightly more than one-half of the patients were revision cases; thus, the results are just as relevant to revision ESS as they are to primary procedures. Human studies of the effect of adrenalin on lidocaine clearance has shown that sensory blockade resolved in volunteers injected with plain lidocaine by 2 hours from infiltration, whereas lidocaine with adrenalin allowed continuing sensory blockade to be present at 5 hours after infiltration. 19 It was interesting to note that the surgical grade remained significantly different between the two groups at all time points and the effect did not appear to wear off with time. However, surgical grade did deteriorate on both the injected and the noninjected sides over time. This was thought to be related to prolonged vasodilatation because of the general anesthetic 20 Previous studies have shown the impact of HR on the surgical field. 20 This study supports these studies of the importance of the heart rate on the surgical grade. CONCLUSION At present, there are no published prospective, blind, randomized controlled trials that evaluate the role of pterygopalatine fossa injection in ESS. The results of this study show a significant improvement in surgical field on the side in which the pterygopalatine fossa injection was performed and that it was a safe maneuver. The finding of HR being an independent factor correlating with surgical field during ESS has been shown previously and this study supports that work. ACKNOWLEDGMENTS Analysis of the data was performed by an independent statistician, J.A. Jones, provided by BiometricsSA. REFERENCES 1. Riegle EV, Gunter JB, Lusk RP, et al. Comparison of vasoconstrictors for functional endoscopic sinus surgery in children. Laryngoscope 102: , Liao BS, Hilsinger RL, Rasgon BM, et al. A Preliminary study of cocaine absorption from the nasal mucosa. Laryngoscope 109:98 102, Blackwell KE, Ross DA, Kapur P, and Calcaterra TC. Propofol for maintenance of general anesthesia: A technique to limit blood loss during endoscopic sinus surgery. Am J Otolaryngol 14: , Boezaart AP, van der Merwe J, and Coetzee A. Comparison of sodium nitroprusside- and esmolol-induced controlled hypoten- American Journal of Rhinology 291

5 sion for functional endoscopic sinus surgery. Can J Anaesth 42: , Saitoh K, et al. Induced hypotension for endoscopic sinus surgery. Masui 51: , Saarnivaara L, Klemola UM, and Lindgren L. Labetalol as a hypotensive agent for middle ear microsurgery. Acta Anaesthesiol Scand 31: , Eberhart LHJ, Folz BJ, Wulf H, and Geldner G. Intravenous anaesthesia provides optimal surgical conditions during microscopic and endoscopic sinus surgery. Laryngoscope 113: , Last RJ. Pterygopalatine fossa. In Last s Anatomy Regional and Applied, 9th ed. McMinn RMH (Ed). Hong Kong: Churchill Livingstone, 459, Premdas CE, and Pitt Ford TR. Effect of palatal injections on pulpal blood flow in premolars. Endod Dent Traumatol 11: , Taiwo YO, and Levine JD. Direct cutaneous hyperalgesia induced by adenosine. Neuroscience 38: , Baron R, and Janig W. Pain syndromes with causal participation of the sympathetic nervous system. Anaesthesist 47:4 23, Lim RK. Sites of action of narcotic and nonnarcotic analgesics: Mechanism of pain and analgesia. Headache 7: , Dunlevy TM, O Malley TP, and Postma GN. Optimal concentration of epinephrine for vasoconstriction in neck surgery. Laryngoscope 106: , Mercuri LG. Intraoral second division nerve block. Oral Surg Oral Med Oral Pathol 47: , Kang SK, White PS, and Cain A. A comparative study of the optical characteristics of commonly used sinoscopes: Do you know where you are looking? Clin Otolaryngol 28:14 17, Schubert MS. Allergic fungal sinusitis: Pathogenesis and management strategies. Drugs 64: , Eberhart LH, Folz BJ, Wulf J, and Geldner G. Intravenous anesthesia provides optimal surgical conditions during microscopic and endoscopic sinus surgery. Laryngoscope 113: , Collins M, Nair S, Kette F, et al. Role of local immunoglobulin E production in the pathophysiology of non-invasive fungal sinusitis. Laryngoscope 114: , Bernards CM, and Kopacz DJ. Effect of epinephrine on lidocaine clearance in vivo: A microdialysis study in humans. Anesthesiology 91: , Nair S, Collins M, Hung P, et al. The effect of beta-blocker premedication on the surgical field during endoscopic sinus surgery. Laryngoscope 114: , e 292 May June 2005, Vol. 19, No. 3

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