Territorial and Extraterritorial Trigeminocardiac Reflex: A Review for the Neurosurgeon and a Type IV Reflex Vignette

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.

Combined Presigmoid-Subtemporal Approach in a Semi-Sitting Position for Petroclival Meningiomas: A Technical Report

The removal of petroclival meningiomas (PMs) is considered a neurosurgical challenge due to the critical mobilization of key neurovascular structures. Limited knowledge about the benefits of operating on patients with PMs using the combined presigmoid-subtemporal approach (CPSA) in a semi-sitting position has precluded its generalizability. We report on ten patients with PMs operated in a semi-sitting position using CPSA. We remark that before the surgical approach was accomplished in our group of patients, the CPSA via semi-sitting position was conducted and standardized in six adult cadaveric heads. The neuroanatomic dissections made in cadavers allowed us to confidently use CPSA in our set of patients. There were no comorbidities, perioperative complications, or deaths associated with the surgical procedure. CPSA via a semi-sitting position can be considered a safe approach to remove PMs.