Definition and Diagnosis of the Trigeminocardiac Reflex: A Grounded Theory Approach for an Update

Giuseppe Dagnini (1866-1928): Discoverer of the Trigemino-Cardiac Reflex and Practical Implications in Neurosurgery and Other Medical Specialties

The authors present the life and art of Giuseppe Dagnini, a renowned Italian physician who was born in Bologna in 1866. He was the chief of the Maggiore Hospital in Bologna and authored valuable scientific works on the trigemino-cardiac reflex which is still applied in modern clinical practice. Dr. Dagnini firstly described the reflex in 1908 postulating that stimulation of one of the 3 branches of the trigeminal nerve triggers the afferent pathway in lowering heart rate. The authors also provide a modern outlook on the clinical implications of the TCR in neurosurgery, neuroanesthesia, and other medical specialties.

Perioperative adverse cardiac events in maxillofacial surgery: A systematic review and meta-analysis

Background and Aims

Maxillofacial surgeries, including procedures to the face, oral cavity, jaw, and head and neck, are common in adults. However, they impose a risk of adverse cardiac events (ACEs). While ACEs are well understood for other non-cardiac surgeries, there is a paucity of data about maxillofacial surgeries. This systematic review and meta-analysis report the incidence and presentation of perioperative ACEs during maxillofacial surgery.

Methods

We included primary studies that reported on perioperative ACEs in adults. To standardise reporting, ACEs were categorised as 1. heart rate and rhythm disturbances, 2. blood pressure disturbances, 3. ischaemic heart disease and 4. heart failure and other complications. The primary outcome was ACE presentation and incidence during the perioperative period. Secondary outcomes included the surgical outcome according to the Clavien-Dindo classification and trigeminocardiac reflex involvement. STATA version 17.0 and MetaProp were used to delineate proportion as effect size with a 95% confidence interval (CI).

Results

Twelve studies (34,227 patients) were included. The incidence of perioperative ACEs was 2.58% (95% CI 1.70, 3.45, I2 = 96.17%, P = 0.001). Heart rate and rhythm disturbances resulted in the greatest incidence at 3.84% among the four categories. Most commonly, these ACEs resulted in intensive care unit admission (i.e. Clavien-Dindo score of 4).

Conclusion

Despite an incidence of 2.58%, ACEs can disproportionately impact surgical outcomes. Future research should include large-scale prospective studies that may provide a better understanding of the contributory factors and long-term effects of ACEs in patients during maxillofacial surgery.

Unstable bradycardia induced by posterior nasal packing: a rare activation of the Trigeminocardiacreflex

A woman in her 40s presented to the emergency department with epistaxis. Anterior nasal packing was unsuccessful in achieving haemostasis. After the exchange of devices and insertion of a posterior nasal pack, the patient developed a junctional rhythm and progressively unstable bradycardia. The rhythm and bradycardia immediately improved following the removal of the posterior nasal pack. This case describes a rare occurrence of Trigeminocardiac reflex (TCR), following an insertion of a posterior nasal pack. Only one other such case has been reported and published. This case highlights the importance of raising awareness of this rare reflex and the need for prompt removal of the triggering cause in such scenarios. TCR can induce a junctional rhythm, which progresses to unstable bradycardia and may lead to asystole in susceptible individuals. The removal of the stimulus resolves the reflex and can result in prompt resolution of the bradycardia and hypotension induced via the TCR.

A case report: A patient rescued by VA-ECMO after cardiac arrest triggered by trigeminocardiac reflex after nasal surgery

RATIONALE

Cardiac arrest (CA) caused by trigeminocardiac reflex (TCR) after endoscopic nasal surgery is rare. Hence, when a patient suffers from TCR induced CA in the recovery room, most doctors may not be able to find the cause in a short time, and standard cardiopulmonary resuscitation and resuscitation measures may not be effective. Providing circulatory assistance through venous-arterial extracorporeal membrane oxygenation (VA-ECMO) can help healthcare providers gain time to identify the etiology and initiate symptom-specific treatment.

PATIENT CONCERNS

We report a rare case of CA after endoscopic nasal surgery treated with VA-ECMO.

DIAGNOSES

We excluded myocardial infarction, pulmonary embolism, allergies, hypoxia, and electrolyte abnormalities based on the relevant examination results. Following a multidisciplinary consultation, clinical manifestation and a review of previous literature, we reasoned that the CA was due to TCR.

INTERVENTIONS

VA-ECMO was established to resuscitate the patient successfully during effective cardiopulmonary resuscitation.

OUTCOMES

ECMO was successfully evacuated a period of 190 minutes of therapy. The patient was discharged home on day 8.

LESSONS

TCR is notable during endoscopic nasal surgery. Our case indicates that CA in operating room is worth prolonged CCPR. The ideal time for ECPR implementation should not be limited within 20 minutes after CCPR.

Heart Rate Changes following Facemask Placement in Infants Born at ≥32+0 Weeks of Gestation

INTRODUCTION

Recent reports have raised concerns of cardiorespiratory deterioration in some infants receiving respiratory support at birth. We aimed to independently determine whether respiratory support with a facemask is associated with a decrease in heart rate (HR) in some late-preterm and term infants.

METHODS

Secondary analysis of data from infants born at ≥32+0 weeks of gestation at 2 perinatal centres in Melbourne, Australia. Change in HR up to 120 s after facemask placement, measured using 3-lead electrocardiography, was assessed every 3 s until 60 s and every 5 s thereafter from video recordings.

RESULTS

In the 15 s after facemask placement, 10/68 (15%) infants had a decrease in mean HR by >10 beats per minute (bpm) compared with their individual baseline mean HR in the 15 s before facemask placement. In 4 (6%) infants, HR decreased to <100 bpm. Nine out of 68 (13%) infants had an increase in mean HR by >10 bpm; 7 of these infants had a baseline HR <120 bpm. In univariable comparisons, the following characteristics were found not to be risk factors for a decrease in HR by >10 bpm: prematurity; type of respiratory support; hypoxaemia; early cord clamping; mode of birth; HR <120 bpm before mask placement. Six out of 63 infants (10%) who had HR ≥120 bpm after facemask placement had a late decrease in HR to <100 bpm between 30 and 120 s after facemask placement.

CONCLUSION

Facemask respiratory support at birth is temporally associated with a decrease in HR in a subset of late-preterm and term infants.

Risk factors associated with trigeminocardiac reflex in patients with trigeminal neuralgia during percutaneous balloon compression: A retrospective cohort study

BACKGROUND

The trigeminocardiac reflex (TCR) is a brainstem reflex commonly elicited during percutaneous balloon compression (PBC) for the treatment of trigeminal neuralgia (TN), which is characterized by drastic hemodynamic disturbances, such as bradycardia, arrhythmias and even cardiac arrest. In order to prevent catastrophic consequences, it is vital to screen the risk factors of TCR during perioperative period. The primary purpose of this study was to identify potential risk factors associated with TCR in patients with TN undergoing PBC, and to summarize the enlightenment of clinical anesthesia management.

METHODS

The clinical data of 165 patients diagnosed with TN undergoing PBC from January 2021 to December 2021 were retrospectively analyzed. TCR was defined as a sudden decrease in heart rate of 20% or more compared with baseline, and / or cardiac arrest, coinciding with the stimulus of any branch of the trigeminal nerve. And a clear cause-effect relationship between heart rate reduction and PBC-related intervention was required. All demographic characteristics as well as surgical and anesthetic data were compared between TCR group and TCR-free group. Univariate and multivariate logistic regression analysis were used to further analyze TCR-related risk factors.

RESULTS

Of the 165 patients enrolled in this study, 73 (44.2%) were male and 92 (55.8%) were female, and the average age was 64.22 ± 9.72 years. The incidence of TCR in the patients with TN during PBC was 54.5%. The results of multivariate regression analysis indicated that the risk factor for TCR was heart rate < 60 beats/min immediately before foramen ovale puncture (OR: 4.622; 95%CI: 1.470-14.531; P < 0.05).

CONCLUSION

Heart rate < 60 beats/min immediately before foramen ovale puncture was independently associated with TCR. Therefore, it is necessary for anesthesiologists to raise heart rate appropriately to prevent TCR during PBC.

Trigeminocardiac Reflex: A Review and Key Implications to Dermatologic Surgery

BACKGROUND

The trigeminocardiac reflex is a common but underreported occurrence that can vary from benign to life threatening. This reflex can be elicited by placing direct pressure on the globe of the eye or from traction of the extraocular muscles, stimulating the trigeminal nerve.

OBJECTIVE

To provide a review of potential stimuli for the trigeminocardiac reflex within dermatologic surgery and to discuss management options for the treatment of the trigeminocardiac reflex.

METHODS

PubMed and Cochrane were used to identify articles and case reports that established scenarios in which the trigeminocardiac reflex was provoked and subsequently how the reflex was managed.

RESULTS

Within the field of dermatologic surgery, the trigeminocardiac reflex can be stimulated during biopsies, cryoablations, injections, laser treatments, Mohs micrographic surgery, and oculoplastic interventions, most often occurring in an office setting. The most common presentations include significant bradycardia, hypotension, gastric hypermobility, and lightheadedness. The most definitive treatment is cessation of the inciting stimulus, monitoring, and symptomatic management. Glycopyrrolate and atropine are common treatments for severe, intractable cases of the trigeminocardiac reflex.

CONCLUSION

The trigeminocardiac reflex, while underreported and underrepresented in dermatologic literature and dermatologic surgery settings, should be considered in the setting of bradycardia and hypotension during dermatologic procedures.

The Influence of Trigeminocardiac Reflex on Postoperative Cardiac Adverse Events in Patients Undergoing Cerebellopontine Angle Tumor Resections: A Case-Control Study

OBJECTIVE

To assess the potential impact of the trigeminocardiac reflex (TCR) on postoperative adverse cardiac events and to identify predictors of the TCR in cerebellopontine angle surgery.

METHODS

Patients undergoing elective cerebellopontine angle surgery from October 1, 2015, to September 30, 2020, were recruited consecutively for this retrospective case-control study. The TCR was evaluated by reviewing electronic anesthesia records and defined as a drop in heart rate was >20%. Controls were identified from the same retrospective cohort and matched by age, sex, and similar (±5 days) surgery date in the ratio of 1:2.

RESULTS

Of 2446 patients, 68 (2.78%) experienced TCR episodes. A total of 97 TCR episodes occurred among the 68 patients. In 2 TCR episodes, severe cardiac complications developed after surgery-myocardial injury in one case and cardiac arrest in the other case. The prevalence of adverse cardiovascular events was higher in the TCR group (60.3% vs. 36.0%, P = 0.001) than in the control group. The independent risk factor for the TCR in the multivariate condition logistic regression was tumor compression of the brainstem (odds ratio = 2.36, 95% confidence interval 1.40-3.95; P = 0.001).

CONCLUSIONS

Intraoperative TCR episodes seemed to be associated with postoperative adverse cardiac events in patients undergoing cerebellopontine angle surgery. Moreover, tumor compression of the brainstem might be a risk factor for TCR episodes.

Paroxysmal Atrial Fibrillation with Rapid Ventricular Response Following COVID-19 Nasopharyngeal Swab: A Case Report

Nasopharyngeal (NP) swab sampling is a simple procedure that has become extremely popular in the coronavirus disease 2019 (COVID-19) era, with hundreds of million specimens collected every day. However, rare but serious complications have been reported following NP swab acquisition. Here we present a case of paroxysmal atrial fibrillation associated with NP specimen collection in a healthy healthcare provider undergoing COVID-19 testing during departmental screening. This response may have been caused by an exaggerated vagal tone triggered by the trigeminocardiac reflex. Less invasive collection methods, such as saliva testing, may be warranted in predisposed individuals.

Prolonged asystole induced by trigeminocardiac reflex accompanied with abnormal heart rate variability during percutaneous balloon compression: a case report

Trigeminocardiac reflex (TCR) can result in bradycardia and even cardiac arrest, and is reversible with elimination of the stimulus. Here, we report the case of a 68-year-old man who experienced cardiac arrest during percutaneous balloon compression for the treatment of trigeminal neuralgia. In this patient, sinus rhythm did not recover after stimulation removal, causing us to successfully perform cardiopulmonary resuscitation (CPR). The patient regained a sinus rhythm and was pretreated with atropine 0.5 mg, allowing the operation to be started again. The operation was completed successfully and the patient experienced no complications. Subsequent heart rate variability (HRV) analysis showed that parasympathetic activity predominated before anesthesia induction and after tracheal intubation. It further elevated during foramen ovale puncture, leading to prolonged asystole. Fortunately, sympathetic activity predominated after atropine was administered, which manifested as an increase in sympathetic activity and a decrease in parasympathetic activity. This could be beneficial for patients with TCR. This case indicates that TCR-related cardiac arrest might not be reversed with stimulus cessation, and atropine played a key role in preventing TCR. Moreover, HRV analysis might be essential for preoperative screening for high-risk patients. We also reviewed the literature for cases of TCR with prolonged asystole.

Repeated ventricular bigeminy by trigeminocardiac reflex despite atropine administration during superficial upper lip surgery: A case report

BACKGROUND

The trigeminocardiac reflex (TCR) is usually caused by an increased parasympathetic tone when pressure or traction is applied to the surrounding tissue of the trigeminal nerve. However, the inexperienced anesthesiologists may have challenges on the management of TCR patients.

CASE SUMMARY

This is the case of an 18-year-old woman diagnosed with hemangioma of the upper lip. During the operation, about 1 h after surgery started, a constant 1:1 premature ventricular complex was detected, and blood pressure was decreased when approaching the deeper part with more strong traction for exposure of the part. Although the management of arrhythmias, such as lidocaine and atropine, was injected, arrhythmia induced by surgical stimulation could not be eliminated completely. As the traction repeated, bradycardia was also repeated, despite injecting additional atropine. Therefore, the anesthesiologist and the surgeon decided to perform the operation only to the extent that the vascular tissue was selectively removed only at the site without the reflex.

CONCLUSION

With TCR, anesthesiologists should perform appropriate monitoring. In addition to proper drug administration, surgeons should be consulted to cope with stopping the surgery and setting the scope of the surgery even if the site is superficial.

Supramuscular upper blepharoplasty approach to orbital roof and/or lower anterior table frontal sinus fractures: A meta-narrative review

BACKGROUND

An approach to orbital roof fractures (ORFs) and/or lower anterior table frontal sinus fractures (LATFSFs) is a challenging task. The conventional coronal approach (CCA) appears to suit multiple/complex fractures of the upper face, while periorbital transcutaneous incisions (PTIs), e.g. gull wing, open sky, butterfly, and Lynch incisions, often impair aesthetic outcomes. The aims of this paper were to provide an overview of the supramuscular upper blepharoplasty approach (SUBA) to ORFs/LATFSFs.

METHODS

Using a meta-narrative review study design, the investigators enrolled published data extracted from PubMed/Medline, Embase, Cochrane Library, and Google Scholar concerning SUBA to ORFs/LATFSFs. Only publications with the highest and most recent level of evidence (LoE) in English, French or German available until 6 May 2022 were included. The LoE were evaluated using the 2011 Oxford Centre for Evidence-Based Medicine (OCEBM)'s classification.

RESULTS

In total, 70 articles were included; however, most contained low LoE. Under general and local anaesthesia, SUBA to ORFs/LATFSFs can be performed safely and appeared to be superior to its submuscular counterpart in terms of fewer risks of adjacent tissue injuries, and speedy operative time (maximal 5 min. in experienced hands).

CONCLUSIONS

In contrast to CCA and PTIs, the SUBA is a minimally invasive approach to the ORF/LATFSF with favourable aesthetic outcomes, direct visualisation of the fracture, quick operative time, rare complications, and easy learning.

Prognostic factors for trigeminocardiac reflex during cerebrovascular intervention operation

Introduction

Trigeminocardiac reflex (TCR) is a brainstem reflexive response of hemodynamic instability during surgery. Identification of risk factors relevant to TCR during cerebrovascular intervention procedures is helpful to efficiently prevent and treat its occurrence. The purpose of this study was to demonstrate the risk factors for Onyx embolization during cerebrovascular intervention operation so as to optimize perioperative management strategies on TCR.

Methods

We performed a retrospective study on the patients with Onyx embolization under general anaesthesia over 6-years period from 2013 to 2018. 354 patients were finally eligible for inclusion, and then divided into TCR group (group T) and control group (group N). Patient characteristics, clinical diagnosis, comorbidities, lesion sites, hemodynamics changes, and complications were compared between two groups. Several multivariable regression models were applied to analyze the risk factors associated with TCR.

Results

TCR occurred in 59 patients (16.7%) among 354 patients. There was no significant difference in patient characteristics between two groups (P > 0.05). During DMSO/Onyx injection, HR and MAP were much lower in group T than group N (P < 0.01). Notably, univariable analysis revealed that the patients with dural arteriovenous fistula (DAVF) and middle meningeal artery being affected were associated with a higher incidence of TCR (P < 0.01). Furthermore, multivariable analysis showed that there was a close link of TCR with DAVF [OR = 4.12; 95% CI (1.83–10.65)] and middle meningeal artery embolization [OR = 3.90; 95% CI (1.58–9.63)]. Further stratified analysis of patients with TCR found that patients with middle meningeal artery embolization were more likely to experience hypotension during TCR episode (P < 0.05). Finally, more incidence of postoperative adverse events was observed when TCR episode (P < 0.05).

Conclusion

We found that DAVF and middle meningeal artery embolization were independent risk factors for TCR episodes during Onyx endovascular embolization, highly likely leading to intraoperative hemodynamics fluctuations and postoperative adverse events.

Case Report: Trigeminocardiac Reflex in Endovascular Recanalization of Intracranial Internal Carotid Artery Occlusion

Background

The trigeminocardiac reflex (TCR) is a unique brainstem reflex that manifests as sudden negative hemodynamic changes. Although rare, TCR may develop during interventional neuroradiology procedures. Intracranial internal carotid artery occlusion (ICAO) is a cause or risk factor of ischemic stroke. Endovascular recanalization is an effective treatment for intracranial ICAO. The occurrence of TCR during the endovascular treatment of intracranial ICAO has not been reported previously.

Methods

We identified and reviewed four intracranial ICAO cases who suffered a sudden negative hemodynamic change during endovascular therapy at our hospital between March 2019 and December 2020.

Results

There were five sudden heart rate and/or blood pressure drops in the four cases; all occurred just after contrast agents were injected. Some angioarchitectural characteristics were common among the four cases. First, the intracranial internal carotid artery distal to the ophthalmic artery was occluded, leaving the ophthalmic artery as the only outflow tract. Second, there were obstructive factors proximal to the end of the guiding catheter, including a vasospasm or dilated balloon. This type of angioarchitecture with a limited outflow tract creates a “blind alley.” The five negative hemodynamic events all recovered: two spontaneously and three after drug administration. Postoperatively, two of the four patients developed ocular symptoms.

Conclusions

Intracranial ICAOs may produce a distinctive angioarchitecture, such as a blind alley, that predisposes patients to TCR. Surgeons should pay special attention to the possibility of TCR during the endovascular recanalization of intracranial ICAO. Low-pressure contrast injections should be attempted, and anticholinergics should be ready for use.

Prophylactic intra-arterial injection of lidocaine: a novel strategy to prevent endovascular embolization-induced trigeminocardiac reflex

BACKGROUND

Trigeminocardiac reflex (TCR) is a brainstem reflex that can lead to hemodynamic instability manifested as bradycardia, decrease/increase of mean arterial pressure (MAP) and, in the worst case scenario, asystole during surgery. The effective intraoperative management of recurrent and profound TCR has yet to be established. This randomized paired study was performed to identify the effect of a prophylactic intra-arterial injection of lidocaine to prevent TCR caused by Onyx embolization during cerebrovascular intervention surgery.

METHODS

A total of 136 patients who received Onyx embolization under general anesthesia were assigned to a control group pretreated with intra-arterial saline injection or a lidocaine group pretreated with an intra-arterial injection of 20 mg lidocaine. Heart rate (HR) and MAP were closely monitored during the embolization procedures and the incidence of TCR, mainly characterized by a decrease in HR of ≥20%, and perioperative adverse events was recorded.

RESULTS

During dimethyl sulfoxide (DMSO)/Onyx injection, HR was much slower in the control group than in the lidocaine group (p<0.05). TCR occurred in 12 patients (17.6%) in the control group (cardiac arrest in 3 patients) with decreased (7 cases) or increased (5 cases) MAP, whereas no TCR was observed in the lidocaine group. Notably, most TCR episodes occurred in patients with dural arteriovenous fistula and middle meningeal artery being affected. The composite adverse events were significantly higher in the control group than in the lidocaine group (p<0.05).

CONCLUSION

This prospective study shows that a prophylactic intra-arterial injection of 20 mg lidocaine could be recommended as a novel strategy to effectively and safely prevent TCR during endovascular embolization.

Evaluation of Trigeminocardiac Reflex in Patients Undergoing Elevation of Zygomatic Fractures

Aim

Trigeminocardiac reflex (TCR) manifests as typical hemodynamic perturbations including a sudden lowering of heart rate, mean arterial blood pressure (MABP), cardiac arrhythmias, and asystole. In literature, TCR has been seen during ocular surgeries, Lefort fractures, and craniofacial surgeries. However, the prevalence of the TCR has not been studied in zygomatic complex fractures . The aim of this study was to assess the prevalence of TCR in patients undergoing elevation with/without fixation of zygomatic complex fractures and isolated zygomatic arch fractures under local anesthesia and general anesthesia and to evaluate the prevalence of TCR in different age groups.

Materials and methods

The study comprised 26 participants diagnosed with zygomatic fractures indicated for surgical intervention. The aim of the study was to find the prevalence of TCR in patients undergoing surgical intervention (elevation of zygomatic complex fractures with/without fixation) under local anesthesia and general anesthesia. The heart rate and blood pressure were measured preoperatively, intraoperatively and postoperatively.

Results

Variation in heart rate was seen in patients undergoing surgery under local anesthesia and general anesthesia. However, a decrease in the heart rate i.e., bradycardia was noted intra-operatively in 75% of the patients operated under local anesthesia. The prevalence of TCR was noted intra-operatively in 23% of cases operated under general anesthesia. No significant changes were seen in the blood pressure of the patients.

Conclusion

In our study, we found out that the prevalence of TCR was more in the patients operated under local anesthesia i.e., 75% of patients. Out of the patients operated under general anesthesia i.e., 23% of patients showed TCR. No significant variations in blood pressure were observed in patients operated under local anesthesia or general anesthesia. The prevalence of TCR was found more often in the age group of 31-45 years in our study.

The Effect of Atropine on Trigeminocardiac Reflex-induced Hemodynamic Changes During Therapeutic Compression of the Trigeminal Ganglion

BACKGROUND

Percutaneous compression of the trigeminal ganglion (PCTG) can induce significant hemodynamic perturbations secondary to the trigeminocardiac reflex (TCR). The aim of this study was to investigate the effect of atropine pretreatment on hemodynamic responses during PCTG for trigeminal neuralgia.

MATERIALS AND METHODS

A total of 120 patients who received PCTG were randomly assigned to control and atropine groups that were pretreated with saline (n=60) and atropine 0.004 mg/kg intravenously (n=60), respectively. Heart rate (HR) and mean arterial pressure (MAP) were measured at 9 timepoints from before induction of anesthesia until the end of the PCTG procedure; the incidence of TCR was also observed.

RESULTS

HR was higher in the atropine compared with control group from the time of skin puncture with the PCTG needle until after the procedure was completed (P<0.05). MAP was also higher in the atropine compared with control group, but only at entry of the needle into the foramen ovale until 1 minute after trigeminal ganglion compression (P<0.05). HR was reduced in both groups during entry of the needle into the foramen ovale and during ganglion compression, but less so in the atropine compared with the control group (P<0.05). MAP increased during PCTG compared with baseline in both groups, but with a larger increase in the atropine group (P<0.05). Two and 52 cases in the control group, and 6 and 1 cases in the atropine group, exhibited a TCR during entry of the needle into the foramen ovale and at ganglion compression, respectively (P<0.05).

CONCLUSION

Pretreatment with atropine was effective in most patients at minimizing abrupt reduction in HR during PCTG.

Unusual Manifestations of the Trigeminocardiac Reflex During Awake Craniotomy: A Case Report and Review of the Literature

The trigeminocardiac reflex (TCR) is triggered by stimulation of a branch of the trigeminal nerve and results in vagally mediated bradycardia, hypotension, apnea, and gastrointestinal hypermotility. In the operating theatre, patients susceptible to TCR are typically under general anesthesia; thus, cardiac abnormalities are the most common manifestation. Our case highlights the less common intraoperative manifestations of gastric hypermotility and apnea in a patient undergoing awake craniotomy for tumor resection. Prompt recognition, removal of stimuli, and airway management prevented catastrophic complications while facilitating completion of the procedure.

The Oculocardiac Reflex: A Review

BACKGROUND

A typical oculocardiac reflex (OCR) is a moderate trigemino-vagal bradycardia elicited by tension on an extraocular muscle (EOM) during strabismus surgery; however, many other orbital stimuli can elicit cardiac slowing including retinopathy of prematurity examination.

METHODS

World literature related to trigeminovagal and oculocardiac reflex covering over 15,000 patients including 51 randomized clinical trials and case reports are analyzed and reviewed. Under an ongoing observational trial in Alaska, anesthetic, patient and surgical influences on routine strabismus surgery using prospective, uniform EOM tension are compared seeking sufficient sample size to characterize this individually widely variable cardiac response.

RESULTS

With adequate sample size, and emphasizing clinical studies controlling type of EOM, muscle tension amount and duration, anticholinergic and opioid medications, the following augment OCR; rapid-acting opioids and dexmedetomidine while OCR is reduced in older patients, the right eye, less EOM tension, deeper inhaled agents, hypocarbia, anticholinergic medications and orbital block. In re-operations, the former are relatively poor predictors of subsequent OCR.

CONCLUSION

Profound bradycardia can occur in almost 10% of strabismus surgery cases without anticholinergic preventive measures, but reliable prediction of OCR remains elusive. With foreknowledge and careful anesthetic monitoring of the patient before EOM manipulation, residual adverse sequelae from OCR are fortunately very rare. Despite well over a century of experience, the teleology for this occasionally dramatic cardiac response to eye surgery is still not known.

Asystole Triggered by the Mouth Opening With a Dental Mouth Gag Under General Anesthesia During Pediatric Oral Surgery: Report of a Rare Case

The trigeminovagal reflex manifests as a sudden onset of bradycardia, hypotension, and cardiac arrest in response to the stimulation of the trigeminal nerve. The incidence of trigeminovagal reflex in maxillofacial surgical procedures is approximately 1.6%. We report a case of asystole in a pediatric patient in whom a dental mouth gag triggered the trigeminovagal reflex during oral surgery. The patient was a 5-year-old boy who was scheduled to undergo extraction of maxillary supernumerary teeth. After tracheal intubation, anesthesia was maintained with sevoflurane and remifentanil. At the beginning of the surgery, his mouth was opened with a dental mouth gag, and electrocardigram showed asystole for 20 seconds. Thereafter, his heart rate spontaneously returned to basal value within 60 seconds. Since sufficient mouth opening was required to conduct the surgery, his mouth was opened again with the gag. When the interincisal distance exceeded about 40 mm, his heart rate suddenly decreased, but spontaneously returned to baseline within 60 second. The subsequent anesthetic course was uneventful.

Brain and Heart Crosstalk During Neurointerventional Procedures: The Role of the Trigeminocardiac Reflex: An Updated Systematic Review

The trigeminocardiac reflex is a well-described brainstem reflex that clinically manifests as bradycardia, hypotension, or apnea. This physiological phenomenon is extensively reported during open neurosurgical procedures, but very few data exist for trigeminocardiac reflex occurrence during neurointerventional procedures. This systematic review aims to provide aggregated information related to the trigeminocardiac reflex during neurointerventional procedures and to improve understanding of the various mechanisms that can incite this unique brain-heart crosstalk.

Asystole due to stimulation of the supraorbital nerve: abrupt and potentially fatal presentation of the trigeminocardiac reflex

We present a case of sudden asystole that was elicited via the trigeminocardiac reflex in a patient undergoing surgery for a frontal sinus fracture. Asystole occurred after mild stimulation of the supraorbital nerve during dissection along the superior orbital rim. Anticholinergics were administered and lidocaine-soaked gauze was applied to the exposed wound. The patient was an athlete and had pre-existing sinus bradycardia. We hypothesise that the severe reflex response was associated with his underlying increased vagal tone. When performing surgery in patients with increased vagal tone, preventative measures to diminish the trigeminocardiac reflex are recommended. Further studies are needed.

Does Topical Proparacaine Improve Postoperative Comfort After Strabismus Surgery?

Background

Strabismus surgery is often performed on children and adults as a quick-turnover, outpatient procedure under general anesthesia. Ideal methods to reduce post-operative pain and nausea are not yet perfected. We postulated that a simple topical anesthetic drop after surgery might help.

Methods

In a prospective study of oculocardiac reflex (OCR) and strabismus surgery, a cohort of ongoing patients either received proparacaine immediately post-op, or none. Co-variables were Intraoperative opioid and OCR, patient age, type of surgery. Several post-operative recovery outcome variables were prospectively monitored.

Results

Sixty strabismus surgery patients (age 15±22 years) received proparacaine 1% while another 80 (16.5±22 years) received none; both received topical antibiotic-steroid ointment. Pain and nausea (Likert scale) were not impacted by covariables complexity of case, age less than 3.5, OCR >33% drop, intraoperative opioid or neuro-status. Immediate post-op heart rate was lower if OCR >33% and if opioids used. Time until discharge was shorter in younger patients. Proparacaine did not impact outcome variables, except in patients younger than 3.5 years when post-op pain was worse.

Conclusion

Post-op topical anesthetic either produced no difference, or worsened post-op pain and recovery. This prospective study does not support the use of topical anesthetic drop to reduce post-strabismus pain and nausea.

Clinical trials registration

NCT03672435, Strabismus Recovery With Proparacaine and Oculocardiac Reflex (OCRprop).

Photic sneeze reflex: another variant of the trigeminocardiac reflex?

The photic sneeze reflex (PSR) is a condition of uncontrollable sneezing episodes in response to bright light. This reflex often manifests as a mild phenomenon but may cause devastating consequences in some situations (aeroplane pilots, car drivers, etc.). Its exact mechanism is poorly understood. Interestingly, the roles of the fifth and tenth cranial nerves, brainstem nuclei and inciting patterns closely mimic a well-known brainstem reflex, known as the trigeminocardiac reflex (TCR). In this critical review, we hypothesize that the PSR can be a variant of the TCR. This concept will lead to a better understanding of the PSR and sharpens the TCR characteristics and open the doors for new research possibilities.

Cardiovascular Collapse in a Patient With Parotid Abscess: Dangerous Cross Talk Between the Brain and Heart: A Case Report

Postsurgical trigeminal neuralgia (TN), although rare, can lead to significant hemodynamic perturbations by triggering the trigeminocardiac reflex (TCR). The combination can lead to diagnostic as well as management challenges for clinicians. We present the case of a patient with a parotid abscess, which developed as a complication of his otolaryngologic surgery, and which led to repeated episodes of symptomatic bradycardia associated with cardiovascular collapse. This case highlights the importance of heightened awareness, early diagnosis, and timely treatment of postsurgical neuropathic pain syndromes to avoid life-threatening complications.

The oculocardiac reflex and depth of anesthesia measured by brain wave

Background

The oculocardiac reflex (OCR), bradycardia that occurs during strabismus surgery is a type of trigemino-cardiac reflex (TCR) is blocked by anticholinergics and enhanced by opioids and dexmedetomidine. Two recent studies suggest that deeper inhalational anesthesia monitored by BIS protects against OCR; we wondered if our data correlated similarly.

Methods

In an ongoing, prospective study of OCR/TCR elicited by 10-s, 200 g square-wave traction on extraocular muscles (EOM) from 2009 to 2013, anesthetic depth was estimated in cohorts using either BIS or Narcotrend monitors. The depth of anesthesia was deliberately varied between first and second EOM tested.

Results

From 1992 through 2013, 2833 cases of OCR during strabismus surgery were monitored. Excluding re-operations and cases with anticholinergic, OCR from first EOM traction averaged − 20.2 ± 21.8% (S.D.) with a range from − 95 to + 25% in patients aged 0.2 to 90 (median 6.5) years. We did not find correlation between %OCR and brain wave for 97 patients with BIS monitoring and 91 with Narcotrend. With intra-patient controls between first and second muscle, the difference in brain wave did not correlate with difference in %OCR for BIS (r = 0.0002, 95% C. I -0.0002, 0.002, p = 0.30) or for Narcotrend (r = − 0.001, 95% C. I -0.004, 0.001, p = 0.32). Secondary multi-variable analysis demonstrated significant association on %OCR particularly with BIS monitor, opioid, propofol and nitrous oxide concentration in the second EOM tensioned. Sevoflurane concentration correlated better with BIS monitor in second and third EOM tension. %OCR correlated with younger age (p < 0.01). OCR with rapid onset was more profound than those with gradual onset (difference in means 18, 95% C. I 10, 26%).

Conclusions

We were unable to confirm a direct correlation between brain wave monitor and OCR when using multifactorial anesthetic agents. The discrepency with other studies probably reflects direct impact of inhalational agent concentration and less deliberate quantification of EOM tension. We found no level of BIS or Entropy EEG monitoring that uniformly prevents OCR.

Trial registry

NCT03663413.

Data: http://www.abcd-vision.org/OCR/OCR%20Brainwave%20de-identified.pdf.

Maxillomandibulocardiac reflex in a dog

Background

The trigeminocardiac reflex (TCR) is a brainstem reflex that may be observed in anaesthesia during surgical procedures stimulating the intracranial or peripheral portion of the trigeminal nerve. The peripheral TCR is divided into the oculocardiac reflex and the maxillomandibulocardiac reflex based on the affected sensory branches of the trigeminal nerve. In veterinary medicine the oculocardiac reflex has been described, however the maxillomandibulocardiac reflex has never been reported.

Case presentation

A 5-year-old male Epagneul Breton was presented for surgical management of an upper lip mass. During surgery, a sudden severe bradycardia and a decrease in systemic arterial blood pressure developed. The occurrence of a maxillomandibulocardiac reflex was suspected on the basis of the temporary link between surgical stimulation and haemodynamic changes. Three doses of atropine were given before starting a dopamine infusion due to lack of response. The dopamine infusion normalized heart rhythm and blood pressure. The dog recovered uneventfully and he was discharged 24 h later with a sinus rhythm and no sign of recurrence of arrhythmias.

Conclusion

The TCR is a rare but potentially life-threatening complication of procedures involving the sensory areas innervated by the three branches of the trigeminal nerve and it may cause bradycardia with hypotension. The use of a β1-adrenergic receptor agonist such as dopamine may be indicated in cases of a refractory response to the conventional treatment with atropine.

The clinical surrogate definition of the trigeminocardiac reflex: Development of an optimized model according to a PRISMA-compliant systematic review

BACKGROUND

The trigeminocardiac reflex (TCR) is defined as sudden onset of parasympathetic dysrhythmias including hemodynamic irregularities, apnea, and gastric hypermotility during stimulation of sensory branches of the trigeminal nerve. Since the first description of the TCR 1999, there is an ongoing discussion about a more flexible than the existing clinical definition. Aim of this work was to create a clinical surrogate definition through a systematic review of the literature.

METHODS

In this meta-analysis study, literature about TCR occurrences was, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement, systematically identified through various search engines including PubMed (Medline), Embase (Ovid SP), and ISI Web of Sciences databases from January 2005 to August 2015. TCR was defined as a drop of heart rate (HR) below 60 bpm or 20% to the baseline. We extracted detailed data about hemodynamic changes and searched for connections between arterial blood pressure (BP) and HR changes during such episodes.

RESULTS

Overall 45 studies harboring 57 patients were included in the study but only 32 patients showed sufficient data for final analyze. HR showed a nonlinear behavior with a "tipping point" phenomena that differs in variance from the central/peripheral (20-30% drop) to ganglion (40-49% drop). BP showed a linear behavior with a "central limit" phenomena not differing in variance in the whole subgroup (30-39% drop). An analyzation of the correlation between BP and HR showed a trend to a linear correlation.

CONCLUSIONS

We can show for the first time that HR is the dominant variable in the TCR and present a new surrogate definition model. This model and the role of BP must be better investigated in further studies.