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Classification of Potential Risk Factors for Trigeminocardiac Reflex in Craniomaxillofacial Surgery
J Oral Maxillofac Surg 68:1317-1321, 2010
Classification of Potential Risk Factors for Trigeminocardiac Reflex in Craniomaxillofacial Surgery Heinz-Theo Lübbers, MD,* Daniel Zweifel, MD, DMD,† Klaus Wilhelm Grätz, MD, DMD,‡ and Astrid Kruse, MD, DMD§ Purpose: Trigeminocardiac reflex (TCR) in craniomaxillofacial surgery can lead to severely life-threat-
ening situations. At least mild forms are probably much more common than the existing surgical literature suggests. Therefore, the aim of this presentation of cases and literature review was to evaluate the predisposing factors leading to a classification of risk factors for potential TCR and to give information concerning preventive measures and management procedures. Patients and Methods: All surgery reports from the Department of Cranio-Maxillofacial and Oral Surgery in the University Hospital in Zurich between 2003 and 2008 were searched for severe intraoperative cardiovascular complications, and a literature review was performed for publications concerning asystole or bradycardia during maxillofacial surgical procedures. Results: Three incidents were revealed in which severe bradycardia— in 2 cases followed by asystoly— had occured. All incidents were successfully managed. Conclusion: All craniomaxillofacial surgeons involved in orbital surgery in general and in the treatment of midface fractures, eyelid surgery, and orthognathic procedures in particular should be aware of the possibility of the TCR and should be familiar with its prevention and therapy. © 2010 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 68:1317-1321, 2010 The surgeon is much more aware of most complications in maxillofacial surgery (eg, bleeding, infections, and injury of nearby structures) than the trigeminocardiac reflex (TCR), of which mild forms regularly appear in this field of surgery. In 1870, Kratschmer described the influence of reflexes on manipulation of the nasal mucosa.1 In 1908, the TCR was first described as an oculocardiac reflex.2 However, descriptions of the occurrence of the reflex during temporomandibular joint surgery and mandibular osteotomies emphasize that the maxillary and mandibular diviReceived from the Department of Oral and Cranio-Maxillofacial Surgery, University Hospital, Zürich, Switzerland. *Consultant. †Resident. ‡Professor and Chairman. §Consultant. Address correspondence and reprint requests to Dr Lübbers: Department of Oral and Cranio-Maxillofacial Surgery, University Hospital, Frauenklinikstraße 24, CH-8091 Zürich, Switzerland; e-mail: [email protected] © 2010 American Association of Oral and Maxillofacial Surgeons
0278-2391/10/6806-0016$36.00/0 doi:10.1016/j.joms.2009.12.039
sions can be involved as well as the ophthalmic branch of the trigeminal nerve. Besides this oculocardiac reflex, the oculorespiratory reflex, which results in a reduction of respiratory rate and volume, has also been mentioned.3 Today, this phenomenon is well known and not just with regard to manipulation of the nasal mucosa. The TCR is characterized by cardiac arrhythmia, ectopic beats, atrioventricular lock, bradycardia, syncope, vomiting, and asystole. This life-threatening condition has been documented during simple zygomatic arch elevations, repositioning of blowout and maxillary fractures, orthognathic surgery, and nasoethmoidal fractures (Table 1). Although this complication occurs only rarely, every head and neck surgeon should be aware of this severe phenomenon. Most authors agree that this reflex is rare, but Matarasso et al state that the oculocardiac reflex occurs in 25% of patients undergoing blepharoplasty.4 Precious and Skulsky reported the reflex in 1.6% of patients undergoing maxillofacial surgeries.5 The highest incidence (between 32% and 90%) has been described in strabismus surgery.6 For craniofacial surgery (Le Fort I osteotomy, midface fracture reduction, elevation of
1317
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TRIGEMINOCARDIAC REFLEX IN CRANIOMAXILLOFACIAL SURGERY
Table 1. OVERVIEW OF PUBLISHED CASES
Surgical Procedure Elevation of zygomatic arch fractures
Insufflation of temporomandibular joint during arthroscopy During orthognathic procedure of the mandible Endoscopic transspenoidal surgery Reposition of nasoethmoidal fractures Blepharoplasty Intraorbital foreign body Periorbital laceration manipulation Mesiodens removal Midface disimpaction Use of mouth prop
Clinical Feature
Authors
Bradycardia Asystole Bradycardia Bradycardia
Shearer et al, 1987 Bainton et al, 1987 Loewinger et al, 1987 Gillespie, 1988 Gomez et al, 1991 Lang et al, 1991 Campbell et al, 1994 Schaller et al, 2008 Baxandall et al, 1988 Rippmann et al, 2008 Yilmaz et al, 2006 Osborn et al, 2008 Webb et al, 2007 Robideaux, 1978 Precious et al, 1990
Asystole Asystole Asystole Bradycardia Asystole Bradycardia Asystole
Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
zygomatic fractures, and temporomandibular joint insufflation) an incidence of 1% to 2%, and for skull base surgery an incidence of 8% to 18%, have been reported.7 Concerning these incidence rates, one must be aware that bradycardia during maxillofacial surgical procedures might happen much more frequently than is published. On the other hand, clinical features like nausea, vomiting, or bradycardia, particularly in children, can also be interpreted as commotio cerebri rather than being attributable to TCR. Therefore, no specific numbers concerning incidence can be given. The aim of the present study was to evaluate severe events of the TCR during surgical procedures performed between 2003 and 2008 and to review the literature to provide information concerning incidence, predisposing factors, and, last but not least, development of a risk classification.
Patients and Methods All surgery reports from the Department of CranioMaxillofacial and Oral Surgery in the University Hospital in Zurich between 2003 and 2008 were searched for severe intraoperative cardiovascular complications. Three other cases are presented, which showed either intra- or perioperative bradycardia and/or asystole due to no other identifiable pathology than the described trigeminocardiac or oculocardiac reflex. Electronic databases (Medline and Cochrane) were searched using a set of predetermined keywords. The search strategy was initially developed and implemented for PubMed but was revised appropriately to suit the other databases. A combination of free text terms with Boolean operators and truncation was used. No restriction was placed on the year or language of publication. The search strategy was devised in consultation with a senior librarian.
The citations retrieved from each database were exported into the EndNote bibliometric management software. Duplicates were discarded. The titles and abstracts were screened, and the hard copies of all potentially relevant articles were retrieved. Their reference lists were manually searched for any related articles. CASE 1
A 66-year-old male patient, who, after tripping and falling down a short flight of stairs, suffered a displaced tripod fracture along with minimally dislocated further fractures of the facial skeleton and subdural hematoma, was referred to the emergency room. His medical history included type II diabetes and myocardial infarction and consecutive coronary artery stenting 10 years before presentation. He showed no signs or symptoms relating to cardiac dysfunction. Due to the subdural hematoma, operative treatment of the facial fractures was postponed for 10 days. The lateral facial fractures were then visualized by an intraoral approach under general anesthetic. On repositioning of the zygoma, the patient first became bradycardic and then asystolic for 23 seconds. The total event lasted for 2 minutes and 11 seconds. Cardiac massage was performed by the surgeon successfully in combination with ongoing ventilation and administration of 0.5 mg atropine IV and 1 mg epinephrine IV through the anesthetist. Because the fracture was not stable, minimal plate fixation was performed. The patient was kept under close supervision for 24 hours postoperatively, and regular checkups were performed during his time as an outpatient. He suffered no permanent damage of cardiac tissue as demonstrated by pre-, intra-, and postoperative electrocardiograms. No further cardiac pathology could be found.
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LÜBBERS ET AL CASE 2
CASE 3
A 50-year-old male patient was referred to the Department of Cranio-Maxillofacial and Oral Surgery in the University Hospital in Zurich because of a massive fronto-basal, mandible, and midface trauma from a car accident, including a contusion of the bulb and a foreign body in the right orbit next to other general injuries. His medical history included hypertonia and hypercholesterolemia, as well as myocardial infarction 3 years before presentation. He showed no signs or symptoms relating to cardiac dysfunction. After primary care the patient was transferred to our hospital for further treatment. On the patient’s arrival the mandible was provisionally treated and preparations were made for computer-assisted surgery 4 days later. Revision of the fronto-basal area was performed as well as reconstruction of both orbits and the right zygoma under navigation control (Fig 1). During surgical manipulation of the severely fractured zygoma, a severe bradycardia occurred, followed by an asystole. Immediately 0.5 mg atropine IV was administered, and the surgical manipulation was stopped. After the episode totalling 120 seconds, the surgery was completed uneventfully. About 72 hours after surgery, another event of bradycardia occurred, with the heart rate dropping to 36 bpm while the patient was still in the intensive care unit. After administration of 0.5 mg atropine IV, the heart rate quickly normalized to 64 bpm. No further pathology was found to explain these incidents.
A 74-year-old female patient was scheduled for extended tumor resection, including orbital extenteration and reconstruction of the soft tissue defect by radial forearm flap, due to T4 squamous cell carcinoma of the orbit. Her medical history did not include any known risks for TCR. Surgery was uneventful until the final manipulations at the optic nerve before the extenteration was done. Despite a prophylactic dose of 0.5 mg atropine IV before the actual extenteration, a bradycardia occurred down to 33 bpm. Without any further measures except for pausing the surgical manipulations, the heart rate normalized to 70 bpm rhythm within 28 seconds. Further surgery and postoperative course were uneventful. No further pathology was found to explain this incident.
Discussion Bradycardia or asystole is a known complication of zygomatic, blowout, and maxillary fractures.8 On presentation the patient suffers bradycardia or even asystole. Because most cases can be hypothesized to present during the actual accident,8-10 some cases of bradycardia during manipulation in orthognathic surgery11 or repositioning of lateral midface fractures5,12,13 have been reported. Besides the aforementioned risk during surgical procedures, delayed TCR within 48 hours after trauma has also been described.14
FIGURE 1. Reconstruction of the right orbit under navigation—pointer on reconstructed floor. Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
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TRIGEMINOCARDIAC REFLEX IN CRANIOMAXILLOFACIAL SURGERY
formation and merges with the efferent path in the nucleus of the vagus nerve, resulting in a chronotropic-inotropic response by a vagal stimulation of the cardiac branch of the vagus nerve in the myocardium (Fig 2).15,16 Kayikcioglu et al mentioned that a minimum period of 15 to 20 seconds of stimulation is necessary to elicit the reflex leading to at least 20% or more reduction in heart rate, or presence of arrhythmias.17 Cha et al have described the critical period during the first few seconds after stimulation when bradycardia and cardiac depression are maximized.18 In addition to cardiac disease, hypoxemia and hypercapnia have both been identified as predisposing factors leading to an increased risk for TCR. Concerning prevention, several points are important. Besides evaluation of at-risk patients (eg, children and patients with a medical history of cardiac disease) and high-risk surgeries (eg, strabismus), some authors suggested using ketamine for anesthetic induction to decrease the oculocardiac reflex in children undergoing strabismus surgery.19,20 Table 2 presents a classification of several risk factors. The first case presented above would be a highrisk patient because of the previously described cardiac disease; the second patient would have a median risk due to the type of surgery and also would be high risk because of the previously described cardiac disease. The third case would be a high risk because of the type of surgery. Allison et al compared sevoflurane with halothane anesthesia for strabismus surgery in children and concluded that fewer dysrhythmias were observed in FIGURE 2. TCR pathway. Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
Table 2. CLASSIFICATION OF SURGICAL RISK FACTORS
Risk
The reflex responsible for this pathology is known under several synonyms, as follows: oculocardiac reflex (Achener-phenomenon), trigeminocardiac, or trigemino-vagal reflex. The oculocardiac reflex is caused by traction of the extraocular muscles or compression of the eyeball, leading to a decrease in pulse rate by the efferent portion of the vagus nerve from the cardiovascular center of the medulla to the heart. This reflex is described not only in surgery of the zygomaticum, but also in mandible procedures.2 A significantly higher incidence has been reported in children,6 but it can be provoked in any patient even without pre-existing cardiac disease. The neuronal signals of the afferent path of the TCR arch are transmitted by the sensory ends of the trigeminal nerve via gasserian ganglion. The afferent path runs along internuncial fibers in the reticular
Surgery
Prevention
Informing the anesthetist Insufflation of directly before the temporomandibular time of the highest joint risk Le Fort I osteotomy Elevation of zygomatic fractures Medium Skull base surgery Informing the anesthetist directly before the time of the highest risk Informing the anesthetist High Ophthalmic surgery directly before the Strabismus surgery time of the highest Orbital extenteration risk fractures in Atropine and/or children with glycopyrolate cardiac disease Ketamine for anesthetic induction Low
Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
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LÜBBERS ET AL
children receiving sevoflurane than in those receiving halothane because the baseline heart rate and respiratory rate are higher with sevoflurane, resulting in a less pronounced bradycardia on stimulation.3 In addition Yilmaz et al mentioned potent narcotic agents, such as sufentanil and alfentanil, and drugs, such as -blockers or calcium channel blockers.14 Another trigger point that has been described is rinsing with cold water (0 to 20°C) at the distribution of the ophthalmic division of the trigeminal nerve.21 Anticholinergic agents, such as atropine and glycopyrrolate, are the drugs of choice in cases of refractory bradycardia or asystole. However, besides the mentioned therapies, recognition of bradycardia is the first step in treatment.22 Predisposing factors besides cardiac disease are hypoxia and hypercarbia, and use of opioids and -blockers. Any of these factors should lead to an upgrade of the risk assessment according to Table 2. In the first case presented here, the patient had experienced myocardial infarction and consecutive coronary artery stenting 10 years before presentation; therefore, he was a high-risk patient. On the other hand, TCR has been identified with a sudden onset of parasympathetic hypotension, apnea, or gastric hypermotility during stimulation of any of the sensory branches of the trigeminal nerve.23 Concerning therapy, in some cases stopping the surgery has resulted in recovery of a normal rhythm; in other cases, anticholinergic drugs and cardiac massage have been mentioned. In every case of low and medium risk in the classification presented here, we recommend informing the anesthesiology team that they should be prepared for mobilization in case of adverse effects. Although TCR is rare in such cases, it presents a typical complication with a significant risk to the patient. We propose that information on TCR should be given as a part of any preoperative procedure. In every high-risk case presented in the classification, we recommend a prophylactic administration of, eg, 0.5 mg atropine IV, right before any surgical manipulation known to be risky for TCR. Preoperative information should be included as part of the informed consent in these cases. Acknowledgment The authors would like to thank Hildegard Eschle, senior librarian of the Dental School at the University Zurich, for helping with the literature research.
References 1. Kratschmer F: Influences of reflexes of the nasal mucosa on breathing and circulatory. Sber Akad wis Wien 2:147, 1870 2. Lang S, Lanigan DT, van der Wal M: Trigeminocardiac reflexes: Maxillary and mandibular variants of the oculocardiac reflex. Can J Anesth 38:757, 1991 3. Allison CE, De Lange JJ, Koole FD, et al: A comparison of the incidence of the oculocardiac and oculorespiratory reflexes during sevoflurane or halothane anesthesia for strabismus surgery in children. Anesth Analg 90:306, 2000 4. Matarasso A: The oculocardiac reflex in blepharoplasty surgery. Plast Reconstr Surg 83:243, 1989 5. Precious DS, Skulsky FG: Cardiac dysrhythmias complicating maxillofacial surgery. Int J Oral Maxillofac Surg 19:279, 1990 6. Blanc VF, Hardy JF, Milot J et al: The oculocardiac reflex: A graphic and statistical analysis in infants and children. Can Anaesth Soc J 30:360, 1983 7. Schaller B, Cornelius JF, Prabhakar H, et al: The trigeminocardiac reflex: An update of the current knowledge. J Neurosurg Anesthesiol 21:187, 2009 8. Kosaka M, Asamura S, Kamiishi H: Oculocardiac reflex induced by zygomatic fracture: A case report. J Craniomaxillofac Surg 28:106, 2000 9. Habal MB, Beart R, Murray JE: Mediastinal emphysema secondary to fracture of orbital floor. Am J Surg 123:606, 1972 10. Stortebecker TP: Posttraumatic oculocardiac syndrome from a neurosurgical point of view: Report of a case. J Neurosurg 10:682, 1953 11. Robideaux V: Oculocardiac reflex caused by midface disimpaction. Anesthesiology 49:433, 1978 12. Bainton R, Lizi E: Cardiac asystole complicating zygomatic arch fracture. Oral Surg Oral Med Oral Pathol 64:24, 1987 13. Loewinger J, Cohen M, Levi E: Bradycardia during elevation of a zygomatic arch fracture. J Oral Maxillofac Surg 45:710, 1987 14. Yilmaz T, Erol FS, Yakar H, et al: Delayed trigeminocardiac reflex induced by an intraorbital foreign body. Case report. Ophthalmologica 220:65, 2006 15. Schaller B, Probst R, Strebel S, et al: Trigeminocardiac reflex during surgery in the cerebellopontine angle. J Neurosurg 90:215, 1999 16. Mirakhur RK, Jones CJ, Dundee JW, et al: I.m. or i.v. atropine or glycopyrrolate for the prevention of oculocardiac reflex in children undergoing squint surgery. Br J Anaesth 54:1059, 1982 17. Kayikcioglu O, Kayikcioglu M, Erakgun T, et al: Electrocardiographic changes during subconjunctival injections. Int Ophthalmol 23:37, 1999 18. Cha ST, Eby JB, Katzen JT, et al: Trigeminocardiac reflex: A unique case of recurrent asystole during bilateral trigeminal sensory root rhizotomy. J Craniomaxillofac Surg 30:108, 2002 19. Choi SH, Lee SJ, Kim SH, et al: Single bolus of intravenous ketamine for anesthetic induction decreases oculocardiac reflex in children undergoing strabismus surgery. Acta Anaesthesiol Scand 51:759, 2007 20. Hahnenkamp K, Honemann CW, Fischer LG, et al: Effect of different anaesthetic regimes on the oculocardiac reflex during paediatric strabismus surgery. Paediatr Anaesth 10:601, 2000 21. Arndt GA, Stock MC: Bradycardia during cold ocular irrigation under general anaesthesia: An example of the diving reflex. Can J Anesth 40:511, 1993 22. Bohluli B, Ashtiani AK, Khayampoor A, et al: Trigeminocardiac reflex: A MaxFax literature review. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 108:184, 2009 23. Schaller B: Trigeminocardiac reflex. A clinical phenomenon or a new physiological entity? J Neurol 251:658, 2004
Classification of Potential Risk Factors for Trigeminocardiac Reflex in Craniomaxillofacial Surgery Heinz-Theo Lübbers, MD,* Daniel Zweifel, MD, DMD,† Klaus Wilhelm Grätz, MD, DMD,‡ and Astrid Kruse, MD, DMD§ Purpose: Trigeminocardiac reflex (TCR) in craniomaxillofacial surgery can lead to severely life-threat-
ening situations. At least mild forms are probably much more common than the existing surgical literature suggests. Therefore, the aim of this presentation of cases and literature review was to evaluate the predisposing factors leading to a classification of risk factors for potential TCR and to give information concerning preventive measures and management procedures. Patients and Methods: All surgery reports from the Department of Cranio-Maxillofacial and Oral Surgery in the University Hospital in Zurich between 2003 and 2008 were searched for severe intraoperative cardiovascular complications, and a literature review was performed for publications concerning asystole or bradycardia during maxillofacial surgical procedures. Results: Three incidents were revealed in which severe bradycardia— in 2 cases followed by asystoly— had occured. All incidents were successfully managed. Conclusion: All craniomaxillofacial surgeons involved in orbital surgery in general and in the treatment of midface fractures, eyelid surgery, and orthognathic procedures in particular should be aware of the possibility of the TCR and should be familiar with its prevention and therapy. © 2010 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 68:1317-1321, 2010 The surgeon is much more aware of most complications in maxillofacial surgery (eg, bleeding, infections, and injury of nearby structures) than the trigeminocardiac reflex (TCR), of which mild forms regularly appear in this field of surgery. In 1870, Kratschmer described the influence of reflexes on manipulation of the nasal mucosa.1 In 1908, the TCR was first described as an oculocardiac reflex.2 However, descriptions of the occurrence of the reflex during temporomandibular joint surgery and mandibular osteotomies emphasize that the maxillary and mandibular diviReceived from the Department of Oral and Cranio-Maxillofacial Surgery, University Hospital, Zürich, Switzerland. *Consultant. †Resident. ‡Professor and Chairman. §Consultant. Address correspondence and reprint requests to Dr Lübbers: Department of Oral and Cranio-Maxillofacial Surgery, University Hospital, Frauenklinikstraße 24, CH-8091 Zürich, Switzerland; e-mail: [email protected] © 2010 American Association of Oral and Maxillofacial Surgeons
0278-2391/10/6806-0016$36.00/0 doi:10.1016/j.joms.2009.12.039
sions can be involved as well as the ophthalmic branch of the trigeminal nerve. Besides this oculocardiac reflex, the oculorespiratory reflex, which results in a reduction of respiratory rate and volume, has also been mentioned.3 Today, this phenomenon is well known and not just with regard to manipulation of the nasal mucosa. The TCR is characterized by cardiac arrhythmia, ectopic beats, atrioventricular lock, bradycardia, syncope, vomiting, and asystole. This life-threatening condition has been documented during simple zygomatic arch elevations, repositioning of blowout and maxillary fractures, orthognathic surgery, and nasoethmoidal fractures (Table 1). Although this complication occurs only rarely, every head and neck surgeon should be aware of this severe phenomenon. Most authors agree that this reflex is rare, but Matarasso et al state that the oculocardiac reflex occurs in 25% of patients undergoing blepharoplasty.4 Precious and Skulsky reported the reflex in 1.6% of patients undergoing maxillofacial surgeries.5 The highest incidence (between 32% and 90%) has been described in strabismus surgery.6 For craniofacial surgery (Le Fort I osteotomy, midface fracture reduction, elevation of
1317
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TRIGEMINOCARDIAC REFLEX IN CRANIOMAXILLOFACIAL SURGERY
Table 1. OVERVIEW OF PUBLISHED CASES
Surgical Procedure Elevation of zygomatic arch fractures
Insufflation of temporomandibular joint during arthroscopy During orthognathic procedure of the mandible Endoscopic transspenoidal surgery Reposition of nasoethmoidal fractures Blepharoplasty Intraorbital foreign body Periorbital laceration manipulation Mesiodens removal Midface disimpaction Use of mouth prop
Clinical Feature
Authors
Bradycardia Asystole Bradycardia Bradycardia
Shearer et al, 1987 Bainton et al, 1987 Loewinger et al, 1987 Gillespie, 1988 Gomez et al, 1991 Lang et al, 1991 Campbell et al, 1994 Schaller et al, 2008 Baxandall et al, 1988 Rippmann et al, 2008 Yilmaz et al, 2006 Osborn et al, 2008 Webb et al, 2007 Robideaux, 1978 Precious et al, 1990
Asystole Asystole Asystole Bradycardia Asystole Bradycardia Asystole
Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
zygomatic fractures, and temporomandibular joint insufflation) an incidence of 1% to 2%, and for skull base surgery an incidence of 8% to 18%, have been reported.7 Concerning these incidence rates, one must be aware that bradycardia during maxillofacial surgical procedures might happen much more frequently than is published. On the other hand, clinical features like nausea, vomiting, or bradycardia, particularly in children, can also be interpreted as commotio cerebri rather than being attributable to TCR. Therefore, no specific numbers concerning incidence can be given. The aim of the present study was to evaluate severe events of the TCR during surgical procedures performed between 2003 and 2008 and to review the literature to provide information concerning incidence, predisposing factors, and, last but not least, development of a risk classification.
Patients and Methods All surgery reports from the Department of CranioMaxillofacial and Oral Surgery in the University Hospital in Zurich between 2003 and 2008 were searched for severe intraoperative cardiovascular complications. Three other cases are presented, which showed either intra- or perioperative bradycardia and/or asystole due to no other identifiable pathology than the described trigeminocardiac or oculocardiac reflex. Electronic databases (Medline and Cochrane) were searched using a set of predetermined keywords. The search strategy was initially developed and implemented for PubMed but was revised appropriately to suit the other databases. A combination of free text terms with Boolean operators and truncation was used. No restriction was placed on the year or language of publication. The search strategy was devised in consultation with a senior librarian.
The citations retrieved from each database were exported into the EndNote bibliometric management software. Duplicates were discarded. The titles and abstracts were screened, and the hard copies of all potentially relevant articles were retrieved. Their reference lists were manually searched for any related articles. CASE 1
A 66-year-old male patient, who, after tripping and falling down a short flight of stairs, suffered a displaced tripod fracture along with minimally dislocated further fractures of the facial skeleton and subdural hematoma, was referred to the emergency room. His medical history included type II diabetes and myocardial infarction and consecutive coronary artery stenting 10 years before presentation. He showed no signs or symptoms relating to cardiac dysfunction. Due to the subdural hematoma, operative treatment of the facial fractures was postponed for 10 days. The lateral facial fractures were then visualized by an intraoral approach under general anesthetic. On repositioning of the zygoma, the patient first became bradycardic and then asystolic for 23 seconds. The total event lasted for 2 minutes and 11 seconds. Cardiac massage was performed by the surgeon successfully in combination with ongoing ventilation and administration of 0.5 mg atropine IV and 1 mg epinephrine IV through the anesthetist. Because the fracture was not stable, minimal plate fixation was performed. The patient was kept under close supervision for 24 hours postoperatively, and regular checkups were performed during his time as an outpatient. He suffered no permanent damage of cardiac tissue as demonstrated by pre-, intra-, and postoperative electrocardiograms. No further cardiac pathology could be found.
1319
LÜBBERS ET AL CASE 2
CASE 3
A 50-year-old male patient was referred to the Department of Cranio-Maxillofacial and Oral Surgery in the University Hospital in Zurich because of a massive fronto-basal, mandible, and midface trauma from a car accident, including a contusion of the bulb and a foreign body in the right orbit next to other general injuries. His medical history included hypertonia and hypercholesterolemia, as well as myocardial infarction 3 years before presentation. He showed no signs or symptoms relating to cardiac dysfunction. After primary care the patient was transferred to our hospital for further treatment. On the patient’s arrival the mandible was provisionally treated and preparations were made for computer-assisted surgery 4 days later. Revision of the fronto-basal area was performed as well as reconstruction of both orbits and the right zygoma under navigation control (Fig 1). During surgical manipulation of the severely fractured zygoma, a severe bradycardia occurred, followed by an asystole. Immediately 0.5 mg atropine IV was administered, and the surgical manipulation was stopped. After the episode totalling 120 seconds, the surgery was completed uneventfully. About 72 hours after surgery, another event of bradycardia occurred, with the heart rate dropping to 36 bpm while the patient was still in the intensive care unit. After administration of 0.5 mg atropine IV, the heart rate quickly normalized to 64 bpm. No further pathology was found to explain these incidents.
A 74-year-old female patient was scheduled for extended tumor resection, including orbital extenteration and reconstruction of the soft tissue defect by radial forearm flap, due to T4 squamous cell carcinoma of the orbit. Her medical history did not include any known risks for TCR. Surgery was uneventful until the final manipulations at the optic nerve before the extenteration was done. Despite a prophylactic dose of 0.5 mg atropine IV before the actual extenteration, a bradycardia occurred down to 33 bpm. Without any further measures except for pausing the surgical manipulations, the heart rate normalized to 70 bpm rhythm within 28 seconds. Further surgery and postoperative course were uneventful. No further pathology was found to explain this incident.
Discussion Bradycardia or asystole is a known complication of zygomatic, blowout, and maxillary fractures.8 On presentation the patient suffers bradycardia or even asystole. Because most cases can be hypothesized to present during the actual accident,8-10 some cases of bradycardia during manipulation in orthognathic surgery11 or repositioning of lateral midface fractures5,12,13 have been reported. Besides the aforementioned risk during surgical procedures, delayed TCR within 48 hours after trauma has also been described.14
FIGURE 1. Reconstruction of the right orbit under navigation—pointer on reconstructed floor. Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
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TRIGEMINOCARDIAC REFLEX IN CRANIOMAXILLOFACIAL SURGERY
formation and merges with the efferent path in the nucleus of the vagus nerve, resulting in a chronotropic-inotropic response by a vagal stimulation of the cardiac branch of the vagus nerve in the myocardium (Fig 2).15,16 Kayikcioglu et al mentioned that a minimum period of 15 to 20 seconds of stimulation is necessary to elicit the reflex leading to at least 20% or more reduction in heart rate, or presence of arrhythmias.17 Cha et al have described the critical period during the first few seconds after stimulation when bradycardia and cardiac depression are maximized.18 In addition to cardiac disease, hypoxemia and hypercapnia have both been identified as predisposing factors leading to an increased risk for TCR. Concerning prevention, several points are important. Besides evaluation of at-risk patients (eg, children and patients with a medical history of cardiac disease) and high-risk surgeries (eg, strabismus), some authors suggested using ketamine for anesthetic induction to decrease the oculocardiac reflex in children undergoing strabismus surgery.19,20 Table 2 presents a classification of several risk factors. The first case presented above would be a highrisk patient because of the previously described cardiac disease; the second patient would have a median risk due to the type of surgery and also would be high risk because of the previously described cardiac disease. The third case would be a high risk because of the type of surgery. Allison et al compared sevoflurane with halothane anesthesia for strabismus surgery in children and concluded that fewer dysrhythmias were observed in FIGURE 2. TCR pathway. Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
Table 2. CLASSIFICATION OF SURGICAL RISK FACTORS
Risk
The reflex responsible for this pathology is known under several synonyms, as follows: oculocardiac reflex (Achener-phenomenon), trigeminocardiac, or trigemino-vagal reflex. The oculocardiac reflex is caused by traction of the extraocular muscles or compression of the eyeball, leading to a decrease in pulse rate by the efferent portion of the vagus nerve from the cardiovascular center of the medulla to the heart. This reflex is described not only in surgery of the zygomaticum, but also in mandible procedures.2 A significantly higher incidence has been reported in children,6 but it can be provoked in any patient even without pre-existing cardiac disease. The neuronal signals of the afferent path of the TCR arch are transmitted by the sensory ends of the trigeminal nerve via gasserian ganglion. The afferent path runs along internuncial fibers in the reticular
Surgery
Prevention
Informing the anesthetist Insufflation of directly before the temporomandibular time of the highest joint risk Le Fort I osteotomy Elevation of zygomatic fractures Medium Skull base surgery Informing the anesthetist directly before the time of the highest risk Informing the anesthetist High Ophthalmic surgery directly before the Strabismus surgery time of the highest Orbital extenteration risk fractures in Atropine and/or children with glycopyrolate cardiac disease Ketamine for anesthetic induction Low
Lübbers et al. Trigeminocardiac Reflex in Craniomaxillofacial Surgery. J Oral Maxillofac Surg 2010.
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children receiving sevoflurane than in those receiving halothane because the baseline heart rate and respiratory rate are higher with sevoflurane, resulting in a less pronounced bradycardia on stimulation.3 In addition Yilmaz et al mentioned potent narcotic agents, such as sufentanil and alfentanil, and drugs, such as -blockers or calcium channel blockers.14 Another trigger point that has been described is rinsing with cold water (0 to 20°C) at the distribution of the ophthalmic division of the trigeminal nerve.21 Anticholinergic agents, such as atropine and glycopyrrolate, are the drugs of choice in cases of refractory bradycardia or asystole. However, besides the mentioned therapies, recognition of bradycardia is the first step in treatment.22 Predisposing factors besides cardiac disease are hypoxia and hypercarbia, and use of opioids and -blockers. Any of these factors should lead to an upgrade of the risk assessment according to Table 2. In the first case presented here, the patient had experienced myocardial infarction and consecutive coronary artery stenting 10 years before presentation; therefore, he was a high-risk patient. On the other hand, TCR has been identified with a sudden onset of parasympathetic hypotension, apnea, or gastric hypermotility during stimulation of any of the sensory branches of the trigeminal nerve.23 Concerning therapy, in some cases stopping the surgery has resulted in recovery of a normal rhythm; in other cases, anticholinergic drugs and cardiac massage have been mentioned. In every case of low and medium risk in the classification presented here, we recommend informing the anesthesiology team that they should be prepared for mobilization in case of adverse effects. Although TCR is rare in such cases, it presents a typical complication with a significant risk to the patient. We propose that information on TCR should be given as a part of any preoperative procedure. In every high-risk case presented in the classification, we recommend a prophylactic administration of, eg, 0.5 mg atropine IV, right before any surgical manipulation known to be risky for TCR. Preoperative information should be included as part of the informed consent in these cases. Acknowledgment The authors would like to thank Hildegard Eschle, senior librarian of the Dental School at the University Zurich, for helping with the literature research.
References 1. Kratschmer F: Influences of reflexes of the nasal mucosa on breathing and circulatory. Sber Akad wis Wien 2:147, 1870 2. Lang S, Lanigan DT, van der Wal M: Trigeminocardiac reflexes: Maxillary and mandibular variants of the oculocardiac reflex. Can J Anesth 38:757, 1991 3. Allison CE, De Lange JJ, Koole FD, et al: A comparison of the incidence of the oculocardiac and oculorespiratory reflexes during sevoflurane or halothane anesthesia for strabismus surgery in children. Anesth Analg 90:306, 2000 4. Matarasso A: The oculocardiac reflex in blepharoplasty surgery. Plast Reconstr Surg 83:243, 1989 5. Precious DS, Skulsky FG: Cardiac dysrhythmias complicating maxillofacial surgery. Int J Oral Maxillofac Surg 19:279, 1990 6. Blanc VF, Hardy JF, Milot J et al: The oculocardiac reflex: A graphic and statistical analysis in infants and children. Can Anaesth Soc J 30:360, 1983 7. Schaller B, Cornelius JF, Prabhakar H, et al: The trigeminocardiac reflex: An update of the current knowledge. J Neurosurg Anesthesiol 21:187, 2009 8. Kosaka M, Asamura S, Kamiishi H: Oculocardiac reflex induced by zygomatic fracture: A case report. J Craniomaxillofac Surg 28:106, 2000 9. Habal MB, Beart R, Murray JE: Mediastinal emphysema secondary to fracture of orbital floor. Am J Surg 123:606, 1972 10. Stortebecker TP: Posttraumatic oculocardiac syndrome from a neurosurgical point of view: Report of a case. J Neurosurg 10:682, 1953 11. Robideaux V: Oculocardiac reflex caused by midface disimpaction. Anesthesiology 49:433, 1978 12. Bainton R, Lizi E: Cardiac asystole complicating zygomatic arch fracture. Oral Surg Oral Med Oral Pathol 64:24, 1987 13. Loewinger J, Cohen M, Levi E: Bradycardia during elevation of a zygomatic arch fracture. J Oral Maxillofac Surg 45:710, 1987 14. Yilmaz T, Erol FS, Yakar H, et al: Delayed trigeminocardiac reflex induced by an intraorbital foreign body. Case report. Ophthalmologica 220:65, 2006 15. Schaller B, Probst R, Strebel S, et al: Trigeminocardiac reflex during surgery in the cerebellopontine angle. J Neurosurg 90:215, 1999 16. Mirakhur RK, Jones CJ, Dundee JW, et al: I.m. or i.v. atropine or glycopyrrolate for the prevention of oculocardiac reflex in children undergoing squint surgery. Br J Anaesth 54:1059, 1982 17. Kayikcioglu O, Kayikcioglu M, Erakgun T, et al: Electrocardiographic changes during subconjunctival injections. Int Ophthalmol 23:37, 1999 18. Cha ST, Eby JB, Katzen JT, et al: Trigeminocardiac reflex: A unique case of recurrent asystole during bilateral trigeminal sensory root rhizotomy. J Craniomaxillofac Surg 30:108, 2002 19. Choi SH, Lee SJ, Kim SH, et al: Single bolus of intravenous ketamine for anesthetic induction decreases oculocardiac reflex in children undergoing strabismus surgery. Acta Anaesthesiol Scand 51:759, 2007 20. Hahnenkamp K, Honemann CW, Fischer LG, et al: Effect of different anaesthetic regimes on the oculocardiac reflex during paediatric strabismus surgery. Paediatr Anaesth 10:601, 2000 21. Arndt GA, Stock MC: Bradycardia during cold ocular irrigation under general anaesthesia: An example of the diving reflex. Can J Anesth 40:511, 1993 22. Bohluli B, Ashtiani AK, Khayampoor A, et al: Trigeminocardiac reflex: A MaxFax literature review. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 108:184, 2009 23. Schaller B: Trigeminocardiac reflex. A clinical phenomenon or a new physiological entity? J Neurol 251:658, 2004