The role of surgical factors eliciting oculocardiac reflex of patients undergoing orbital tumor surgery: a retrospective study.

PURPOSE: Orbital tumors are an interdisciplinary disease, and surgery is one of the main treatment methods. The oculocardiac reflex (OCR) is a condition of surgery for orbital tumors. The aim of this study was to investigate whether there is an association between many surgical factors and the incidence of OCR in orbital tumor surgery. METHODS: Comparisons were made between patients with and without OCR using the Mann-Whitney test, Fisher's exact test, and Chi-square test. When comparing multiple groups (groups > 2), to explain which two groups had differences, post hoc testing was used for analysis, and the differences between groups were judged according to the adjusted standardized residuals. RESULTS: The results showed that the incidence of intraoperative OCR was different based on the different exposed operative field locations (p = 0.021). The OCR incidence in those with lesions involving the orbital apex and lesions adhering to extraocular muscles was higher than that of others (p < 0.001 and p = 0.003). In addition, multivariate logistic regression analysis revealed that orbital apex involvement and extraocular muscle adhesion were highly associated with a higher incidence of OCR (p < 0.001 and p = 0.013), while the operative field located in the lateral-superior orbit was highly associated with a lower incidence of OCR (p = 0.029). CONCLUSION: In orbital tumor surgery under general anesthesia, lesions involving the orbital apex and lesion adhesion to the extraocular muscles were independent risk factors for OCR, and an operative field located in the lateral-superior orbit was a protective factor for OCR.

Effect of Ice Slush on Reducing the Oculocardiac Reflex During Strabismus Surgery.

BACKGROUND: The aim of this study was to explore whether ice slush (IS) causing local hypothermia can effectively inhibit the oculocardiac reflex (OCR) during strabismus surgery. METHODS: This prospective, randomized, double-blind study included 58 patients with concomitant strabismus scheduled for lateral rectus (LR) recession under general anesthesia. Patients were randomly allocated to receive IS (IS group) or standard treatment (control group) with sterile saline at room temperature before surgery. OCR was defined as a sudden decrease in heart rate (HR) of >15% from baseline. If one incidence of the OCR was found in 1 patient in any stage (0/I/II/III), the patient was defined as an OCR responder, and the incidence of overall OCR was the incidence of OCR responders. The primary outcome was the incidence of overall OCR during all stages of the surgery, which was analyzed by the Z test and computed based on the absolute risk difference with 2-sided 95% confidence intervals (CIs) using the Newcombe method. RESULTS: The overall OCR occurred in 19 of 29 patients (62.5% [95% CI, 45.7-82.1]) in the IS group and 28 of 29 patients (96.6% [95% CI, 82.2-99.9]) in the control group (absolute risk difference, -31.0% [95% CI, -49.4 to -11.0]; Z test, P < .001), which demonstrated that the incidence of overall OCR in IS group was significantly lower than that in the control group. CONCLUSIONS: IS on the ocular surface causing local hypothermia is a promising and easily accessible method to reduce the overall OCR, which can improve the safety of strabismus surgery.

[Advances in the development of ocular cardiac reflex in extraocular muscle surgery].

Ocular cardiac reflex (OCR) usually occurs in ophthalmic surgery, especially in extraocular muscle(s) surgery. OCR generally can cause sinus bradycardia, arrhythmia, reduced atrial pressure, ventricular tachycardia, ventricular fibrillation, ventricular doublet, dizziness, nausea and other symptoms. Severe cases will appear cardiac arrest, respiratory arrest, etc. Recent studies on the mechanism of OCR and the relationship between surgical operation and anaesthesia in extraocular muscle surgery and the occurrence of OCR are reviewed in this paper in order to reduce the occurrence of OCR and treatment of OCR in extraocular muscle surgery.

White-Eyed Orbital Blowout Fracture With Oculocardiac Reflex Secondary to Extraocular Entrapment in a Pediatric Patient.

White-eyed orbital blowout fractures in the pediatric population can present with acute onset diplopia, ophthalmalgia, and abnormal duction. These findings are attributed to the tendency of younger bone to break and reapproximate owing to greater elasticity. This phenomenon, commonly referred to as the greenstick fracture, increases the risk of entrapment of surrounding soft tissue structures in orbital floor fractures. Further concern arises in the presence of an oculocardiac reflex, which requires urgent intervention to prevent serious bradycardia. Prolonged entrapment can go unnoticed and result in irreversible ischemic damage to entrapped tissues. This case discusses the presentation 16-year-old female who sustained a left sided, white-eyed blowout fracture from a face-first ground level fall. On admission, she displayed restrictive strabismus and mild periorbital edema around the left eye. Vertical gaze was restricted when looking inferiorly on the affected side. With sustained upward gaze, her heart rate decreased from 99 to 81 beats per minute. High-resolution non-contrast computed tomography scans of the head showed entrapment of the inferior rectus muscle and periorbital fat. Liberation of entrapped tissues with reduction of bony segments was performed urgently, utilizing a MEDPOR® Titan 3D orbital floor plate and secured with two screws. The patient had an uneventful postoperative period and showed considerable improvements in periorbital edema, duction, and ophthalmalgia on the affected side. In addition, the oculocardiac reflex could no longer be elicited on prolonged upward gaze. Mild and improving paresthesia was noted in the maxillary distribution of the left trigeminal nerve. Sensory deficits like this are the result of fracture communication with the infraorbital canal, which may cause irritation of the infraorbital nerve responsible for sensation by the maxillary division. By postoperative week 7, she had complete resolution of periorbital edema, indiscernible duction abnormalities, and complete healing of surgical incision sites, and an oculocardiac reflex could not be elicited.

Reduction of oculocardiac reflex with Tetracaine eye drop in strabismus surgery.

INTRODUCTION: Recently, to reduce the incidence of oculocardiac reflex (OCR) in strabismus surgery, retrobulbar block and anticholinergic drugs or local anesthesia are also used. The present study evaluated the effects of Tetracaine eye drop as a topical nerve blocker on OCR during strabismus surgery. METHODS AND MATERIALS: In this randomized trial, 70 strabismus surgery candidates were randomly divided into placebo or synthetic teardrop (E) and Tetracaine eye drop (T) groups, so 3 drops of each solution were dropped in four directions of patients' eye immediately after applying anesthesia and before surgery. The incidence and severity of OCR during the stages of muscle release and incision (cutting), hemodynamic changes, the required time for OCR recovery and atropine dose were assessed. RESULTS: OCR was more seen in release phase compared to cutting phase. There were no significant differences between two group regarding the incidence and severity of OCR in the release phase (p > 0.05), but the incidence and severity of OCR in the cutting phase was more in group E than group T (p = 0.02, for both). The duration of OCR improvement (p-value = 0.74) and Atropine consumption (p-value = 0.92) did not differ between the groups. CONCLUSION: Tetracaine eye drop only reduces the incidence and severity of OCR during the incision stage of strabismus surgery.

Effects of an infratrochlear nerve block on reducing the oculocardiac reflex during strabismus surgery: a randomized controlled trial.

PURPOSE: To determine whether an infratrochlear nerve block (ITB) can reduce the oculocardiac reflex (OCR) during strabismus surgery on the medial rectus muscle (MR). METHODS: This prospective, randomized single-masked study included 60 patients with intermittent exotropia scheduled for unilateral MR resection/lateral rectus recession under general anesthesia. Patients were randomly allocated to receive a regional nerve block of the infratrochlear nerve (ITB group) prior to surgery or standard treatment without a nerve block (control group). The OCR was defined as a sudden decrease in heart rate of ≥ 15% from baseline. Changes in heart rate (HR) and the incidence of the OCR were measured during the three stages of surgery applied to the MR in each group: conjunctival incision, muscle dissection, and muscle traction. RESULTS: There were no intergroup differences in patient demographics or baseline HR. The mean HRs during conjunctival incision, muscle dissection, and muscle traction were 94, 90, and 96 bpm, respectively, in the ITB group, and 85, 68, and 84 bpm in the control group; the corresponding OCR incidence rates were 3, 20, and 10%; and 7, 87, and 38%. The HR was higher and the OCR incidence was lower in the ITB group than in the control group during muscle dissection and traction (all p < 0.05). CONCLUSIONS: An ITB maintains a stable HR and reduces the OCR during surgery on the MR. The ITB is less invasive and easily accessible to a surgeon, and can help improve the safety of strabismus surgery.

Surgical factors affecting oculocardiac reflex during strabismus surgery.

BACKGROUND: To investigate surgical factors associated with the occurrence of oculocardiac reflex (OCR) and changes in heart rate (HR) during strabismus surgery. METHODS: Patients who underwent strabismus surgery under general anesthesia were enrolled in this study. The HR during surgery was measured at baseline, and at the following points during surgery: traction of the muscle, maximal increase after traction (adrenergic phase), and the cutting of the muscle. OCR was defined as an HR reduction of more than 20% at traction of the muscle, when compared to baseline HR. The HR at each stage during the surgery was compared between patients with and without OCR. RESULTS: A total of 162 operated muscles from 99 patients were enrolled. The incidence of OCR was 65% in patients. In patients with two muscle surgeries, there were significantly more OCRs in the first operated muscle than in the second operated muscle (p < 0.01). The difference in the decrease in HR in patients with OCR was significantly lower than that in patients without OCR at traction of the muscle, the adrenergic phase, and the cutting of the muscle (all, p < 0.01). The first operated muscle was a significant risk factor associated with the occurrence of OCR (OR = 3.95, p < 0.01). CONCLUSION: The first operated muscle in patients with two muscle surgeries was a significant risk factor for OCR. Decreased HR at the traction of the muscle during surgery did not fully recover in patients with OCR.

Oculocardiac Reflex in an Orbital Fracture Without Entrapment.

Large orbital fractures in older patients are infrequently associated with an exaggerated oculocardiac reflex. This report describes the case of a patient in his 40s with a large right orbital floor and medial wall fracture without radiographic evidence of extraocular muscle compression or entrapment who developed severe nausea and bradycardia with movement of his affected eye. The patient exhibited bradycardia to 17 beats per minute during the initial examination and was taken urgently to the operating room for reconstruction of the right orbital floor and medial wall. Additional episodes of bradycardia intraoperatively were responsive to glycopyrrolate. After the procedure, the patient's pain was decreased, a normal range of motion was restored, and the bradycardia and nausea resolved. An explanation for induction of the oculocardiac reflex is considered in the absence of clinical or radiologic entrapment because large orbital fractures are not often considered to induce this reflex.

Oculocardiac Reflex as a Result of Intraorbital Trauma.

BACKGROUND: The oculocardiac reflex is a decrease in heart rate caused by ocular compression or traction upon the extraocular musculature. Multiple instances of this phenomenon have been described in anesthesia, trauma, craniofacial, and ophthalmology literature, but there is a sparsity of documentation in the emergency medicine literature. CASE REPORT: We describe the observation and management of the oculocardiac reflex in a 26-year-old man with retrobulbar hematoma and intraocular trauma caused by a self-inflicted gunshot wound. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Prompt recognition of the oculocardiac reflex is important for the emergency physician given the common occurrence of craniofacial trauma and the potentially devastating consequences if not recognized and addressed.

Oculocardiac Reflex during Strabismus Surgery: Experience from a Tertiary Hospital.

PURPOSE: To evaluate the incidence of the oculocardiac reflex (OCR) and its associated risk factors during strabismus surgery at a tertiary referral center. METHODS: Over a 2-year period, all strabismus surgery candidates were enrolled in the study. OCR was defined as heart rate reduction ≥15% after traction on extraocular muscle(s). The rate of OCR was determined and possible associations were explored. Variables included age, gender, type of strabismus, nature of surgery (weakening versus strengthening), specified extraocular muscle, times of surgery, and the sequence of operated muscles (eg, first, second, or third operated muscle). We avoided the use of atropine pre- and postoperatively. RESULTS: Seventy-six patients with mean age of 15±12 years were enrolled; 51.3% of subjects were male. OCR occurred in 65 out of 76 (85.5%) patients and with 84 out of 173 (48.6%) operated muscles. OCR was more common in subjects less than 20 years of age; however, it showed a decreasing trend afterwards. OCR was more frequent during operation on cyclovertical muscles than horizontal recti (P=0.02). Moreover, during procedures on horizontal rectus muscles, OCR was more common if baseline heart rate was more than 61 (P=0.008). OCR was not correlated with gender, type of strabismus, nature of surgery, times of the surgery, or the sequence of operated extraocular muscles. CONCLUSIONS: The great majority of patients undergoing strabismus surgery, especially younger subjects, those undergoing operation on cyclovertical muscles, and subjects with higher baseline heart rate, experience OCR during strabismus surgery. During surgery on cyclovertical muscles, the amount of pull is usually more due to more difficult exposure.

[Contact lens dynamometry influences the systemic blood circulation: clinical significance]. / Die Kontaktglasdynamometrie beeinflusst den Systemkreislauf: Folgerungen für die Praxis.

BACKGROUND: The diastolic and systolic pressure in the ophthalmic artery (OAPdia, OAPsys) as well as the venous pulsation pressure (VPP) can be determined by contact lens dynamometry (CLD). With these parameters, carotid artery stenosis, ocular perfusion, e.g., in glaucoma patients and the cerebrospinal pressure can be examined indirectly. In the underlying study comparative data were collected and it was investigated to what extent CLD itself leads to changes of the systemic blood pressure. SUBJECTS/METHODS: In the course of a prospective trial CLD was performed in 162 eyes of 81 healthy volunteers (mean age 41.0 ± 17.3 years). VPP, OAPdia and OAPsys were measured. A mean was calculated from 5 single readings. Directly before and after CLD automated blood pressure measurements according to Riva-Rocci (RR) and the heart rate were obtained in both arms. RESULTS: In the entire group, the mean VPP was 21 ± 9 mmHg on the right side and 19 ± 8 mmHg on the left side. The mean OAPdia was 60 ± 14 mmHg on the right and 67 ± 14 mmHg on the left side. The mean OAPsys was 91 ± 17 and 101 ± 21 mmHg, respectively. The mean variation coefficient from 5 single readings was 13/16 % for VPP (right/left), 7.4/8.2 % for OAPdia and 6.2/6.2 % for OAPsys. The difference between right and left eyes concerning OAPdia and OAPsys was statistically significant (Wilcoxon test; p < 0.001). VPP and OAPsys were not correlated with age, OAPdia showed a weak correlation with age on the right side (Spearman R = 0.23; p = 0.03). Blood pressure (RR) dropped from a mean 137/84 to 135/82 mmHg in the right arm and from 135/84 to 132/83 mmHg in the left arm. The change of the diastolic values of the right side and of the systolic values of the left side reached statistical significance (p < 0.05). The difference of the systolic blood pressure and the heart rate before and after CLD were weakly correlated (Spearman R = - 0.28; p = 0.01). The extent of the systemic blood pressure drop was not correlated with the maximum force affecting the globe. CONCLUSIONS: The slightly lower blood pressure after CLD could be related to the oculocardiac reflex. This has to be confirmed in further trials with continuous blood pressure determination. In agreement with literature reports, significant differences between right and left eyes were found regarding OAPdia and OAPsys.

The oculocardiac reflex in aponeurotic blepharoptosis surgery.

The purpose of this study was to investigate the correlation between the oculocardiac reflex (OCR) and blepharoptosis surgery for safe eyelid surgery. Fifty-four consecutive patients with bilateral aponeurotic blepharoptosis were enrolled in this study. Changes in electrocardiography (ECG) monitoring were recorded during surgery. Preoperative pressing on the globe and intraoperative stretching of the levator aponeurosis were also carried out and the occurrence rate of the OCR was recorded. A positive OCR was observed in 12 patients (22.2%) in the preoperative globe-pressing test, whereas a positive OCR was observed in 22 patients (40.7%) in the levator-stretching test. The levator-stretching test did not indicate a significant difference in the rate of heart rate decrease with respect to laterality. No correlation was observed between age and the occurrence of OCR. On the other hand, there was a significant difference in the percentage of heart rate decrease between patients with positive OCR and negative OCR as determined in the globe-pressing test (mean = 13.1% vs. 5.4%). During the practical operative manoeuvre, no bradycardia was observed in any case. This study confirmed that a rapid and strong traction of levator aponeurosis induces the OCR regardless of laterality and age. Atraumatic and gentle handling are essential to prevent OCR. The preoperative globe-pressing test may be an index of the OCR in reflex-prone patients. Intraoperative ECG monitoring will be useful for early onset detection, although positive OCR was not observed in any patient during the practical surgical manoeuvre.

Different onset pattern of oculocardiac reflex in pediatric medial wall blowout fractures.

PURPOSE: We report the 2 pediatric patients who had radiographic confirmation of a rare case of medial orbital wall "trapdoor" fracture with extraordinary symptoms of oculocardiac reflex (OCR). METHODS: This was a small interventional case series. RESULTS: This is the retrospective report of 2 boys (13 and 10 years old) who developed diplopia, pain, nausea/vomiting, and general malaise following blunt trauma. However, the onset pattern of OCR was absolutely different: delayed onset of OCR just following therapeutic forced duction test to treat the orbital content herniation in the first case and a sudden onset after injury in the second case. In both cases, urgent surgery led to complete normalization of ocular motility. CONCLUSIONS: Prompt diagnosis and proper treatment are critical to maximize clinical outcome for this rare and critical trauma.

Characterization of the oculocardiac reflex during compression of the globe in Beagle dogs and rabbits.

OBJECTIVE: This investigation characterizes the occurrence of oculocardiac reflex (OCR) in conscious rabbits and dogs by observing the effect of an ocular compression stimulus on heart rate (HR). ANIMALS STUDIED: Thirty-four clinically healthy adult rabbits and 15 clinically healthy adult Beagle dogs were studied. PROCEDURES: An electrocardiogram was used to record the heart rhythm and HR continuously. Digital pressure was exerted over the eyelid on right eye, left eye and both eyes together for 1 min, with one-minute intervals between each compression. Variations in HR were observed in each minute by counting complexes on the electrocardiographs. RESULTS: There were no differences in HR between stages without ocular compressions both in dogs and in rabbits. HR reduction caused by ocular compression was statistically significant in rabbits only when both eyes were compressed in contrast with all stages without compression. In dogs, a statistically significant reduction in HR was seen during compression of just the right eye or the left eye compared with the baseline HR, and when both the right and left eyes were compressed together compared with baseline or after compression of the right eye. In dogs, compression of individual eyes produced a change similar to that seen during compression of both eyes. CONCLUSIONS: This study shows that OCR can occur during experimental ocular compression in conscious rabbits and Beagle dogs and characterizes the reduction in HR. Knowledge of this physiological response is important for veterinary anesthetists and ophthalmologists during ophthalmic surgery or eye manipulations.

Oculocardiac reflex in a medial orbital wall fracture without clinically evident entrapment.

In this report, we describe a patient with a medial wall orbital fracture, who presented with vasovagal-like symptoms secondary to an oculocardiac reflex. This case is unusual because the patient had no other clinical evidence of muscle entrapment. A 15-year-old male presented with daily 5-10 min episodes of dizziness, light headedness, and nausea consistent with a vasovagal reaction. On examination, the patient had full extra ocular motility and was orthotropic in all fields of gaze. On computed tomography a comminuted medial orbital wall fracture was identified. The adjacent medial rectus muscle was in normal position, but was "rounded" relative to the contralateral side. The patient underwent fracture repair with immediate resolution of all symptoms. Symptoms related to a vasovagal response may occur with orbital fractures despite normal extra ocular motility. Presumably this relates to tension or pulling on an extra ocular muscle, which is not to a degree that alteration in function is appreciable clinically.

Orbital fractures in children: a review of outcomes.

The third most common facial fractures in children are fractures of the orbit, and the medial wall and floor are the commonest sites affected. The aetiology, clinical presentation, and timing of operation all differ from those of adults. If there are few or no clinical signs, but oculocardiac reflex is present, it is highly suggestive of trapdoor injury. This retrospective study includes all consecutive children (younger than 18 years) referred with confirmed fractures of the orbital floor over a 5-year period (2005-2010). A total of 24 patients were identified with a mean age of 13.5 years, and most injuries were secondary to falls. Isolated injury to the orbital floor occurred in 14 (58%); the rest involved other fractures of the orbital wall or face, or both. There were 11 trapdoor fractures (46%), and 9 open blow-out fractures (38%). Overall, nausea and vomiting occurred in 13 patients (54%); 8 of these had trapdoor fractures. Most patients had operations (22, 92%), and the mean time to operation was 4 days. Complications increased with delays to theatre. Those operated on within 1 day had fewer complications than those who had operations after 3 days. Postoperatively, diplopia (n=6/11) and restricted eye movement (n=3/11) were associated with trapdoor injury, while enophthalmos (n=1/9) and paraesthesia (n=3/9) were related to open blow-out fractures. To reduce compromised outcomes, prompt operation is warranted in all children with fractures of the orbital floor regardless of the configuration.