Generalized seizures and transient contralateral hemiparesis following retrobulbar anesthesia: a case report

Cardiovascular Responses to Nasal Stimulation Under Ethmoidal-Maxillary Nerve Block and Lidocaine Gel in Anesthetized Beagles

This study aimed to compare the effect of ethmoidal-maxillary nerve block (EMBLOCK) and topical application of 2% lidocaine gel (LGEL) on cardiovascular variables (heart rate and arterial blood pressure) during mechanical stimulation of the nasal cavity. The working hypothesis was that both techniques (EMBLOCK and LGEL) similarly blunt the cardiovascular responses to the stimulation. Six beagles were anesthetized using alfaxalone and isoflurane on three occasions with each treatment (EMBLOCK, LGEL, and control) in random order. The nasal cavity from the nose tip to the medial canthus was stimulated with a standard-tip cotton swab, and cardiovascular variables were recorded before and after stimulation. The maximum increases in heart rate and blood pressure were significantly smaller in EMBLOCK and LGEL than in the control. There was no significant difference between EMBLOCK and LGEL. Therefore, although further clinical studies are required, EMBLOCK and LGEL can be used because both EMBLOCK and LGEL attenuated the cardiovascular response to mechanical stimulation of the nasal cavity in dogs.

A Case of Brainstem Anesthesia after Retrobulbar Block for Globe Rupture Repair

Purpose

To present a rare case of brainstem anesthesia from retrobulbar block and discuss evidence-based methods for reducing the incidence of this complication.

Case

A 72-year-old female, was given a retrobulbar block of 5 mL of bupivacaine 0.5% for postoperative pain management, after a globe rupture repair under general anesthesia. Prior to injection, the patient was breathing spontaneously via the anesthesia machine circuit and had not received any additional narcotics/muscle relaxants for 2.5 hr (with full recovery of neuromuscular blocking agent after anesthetic reversal). Over 7 min, however, there was a steady increase in ETCO₂ and the patient became apneic, consistent with brainstem anesthesia. She remained intubated and was transported to the postanesthesia care unit for prolonged monitoring, with eventual extubation. Discussion. Brainstem anesthesia is an important complication to recognize as it can lead to apnea and death. The judicious use of anesthetic volume, shorter needle tips, and mixed formulations can help reduce the chance of brainstem anesthesia. Observation of the contralateral eye 5–10 minutes after injection for pupillary dilation, and prior to surgical draping, can help identify early CNS involvement.

Patient quality of recovery on the day of surgery after propofol total intravenous anesthesia for vitrectomy: A randomized controlled trial

BACKGROUND

Vitrectomy under general anesthesia is considered as a candidate for ambulatory surgery. An anesthetic method with high quality of postoperative recovery should be selected for successful ambulatory surgery. We thus compared quality of postoperative recovery on the day of vitrectomy using the Quality of Recovery (QoR)-40 questionnaire between propofol total intravenous anesthesia (propofol group) and desflurane inhalation anesthesia (desflurane group) as the 2 representative anesthetic methods.

METHODS

Eighty-four patients (20-80 years old) undergoing elective vitrectomy under general anesthesia were randomized into 2 groups. The propofol group received propofol and remifentanil using effect-site target-controlled infusion (TCI), and the desflurane group received desflurane inhalation and remifentanil using effect-site TCI. We assessed quality of recovery at 6 hours after surgery through interviews using the QoR-40 questionnaire. We also collected data related to recovery and complications during emergence and recovery period.

RESULTS

The median of QoR-40 score on the day of surgery was significantly higher in the propofol group than that in the desflurane group (181.0 vs 169.5, respectively; P = .033). In particular, propofol group had significantly higher scores for physical comfort and physical independence dimensions. The amount of remifentanil administered was significantly higher, and the emergence time was significantly longer in propofol group. However, there were no significant differences in other complications between the 2 groups.

CONCLUSIONS

Propofol total intravenous anesthesia provided significantly better quality of recovery on the day of surgery than desflurane inhalation anesthesia.

The Knowledge of Eye Physicians on Local Anesthetic Toxicity and Intravenous Lipid Treatment: Questionnaire Study

Objectives

To evaluate the knowledge of ophthalmologists regarding local anesthesia toxicity syndrome (LATS) and intravenous lipid emulsion used in treatment, and to raise awareness of this issue.

Materials and Methods

A questionnaire comprising 14 questions about demographics, local anesthesia (LA) use, toxicity, and treatment methods was administered to ophthalmologists at different hospitals.

Results

The study included 104 ophthalmologists (25% residents, 67.3% specialists, 7.7% faculty members) with a mean age of 35.71±6.53 years. The highest number of participants was from state hospitals (65.4%), and 34.6% of the physicians had been working in ophthalmology for more than 10 years. Seventy-six percent of the participants reported using LA every day or more than twice a week, but 56.7% had received no specific training on this subject. No statistically significant difference was observed between different education levels and the rates of training (p=0.419). Bupivacaine was the most preferred LA and the majority of respondents (97.1%) did not use a test dose. Allergy (76%) and hypotension (68.3%) were the most common responses for early findings of LATS, while cardiac arrest (57.4%) and hepatotoxicity (56.4%) were given for late findings. The most common responses concerning the prevention of LATS included monitorization (72.4%) and use of appropriate doses (58.2%). Symptomatic treatment was selected by 72.4% of respondents and cardiopulmonary resuscitation and antihistamine treatment by 58.8%. Of the ophthalmologists in the study, 62.5% had never encountered LATS. The use of 20% intravenous lipid emulsion therapy for toxicity was known by 65% of the physicians, but only 1 participant stated having used it previously.

Conclusion

The importance of using 20% lipid emulsion in LATS treatment and having it available where LA is administered must be emphasized, and there should be compulsory training programs for ophthalmologists on this subject.

Development of an ultrasound-guided technique for retrobulbar nerve block in dromedary camels: a cadaveric study

OBJECTIVE

Description of an ultrasound (US)-guided technique for retrobulbar nerve blockade in dromedary (Camelus dromedarius) cadavers.

STUDY DESIGN

Prospective experimental cadaveric study that was carried out in three phases: phase I: anatomical dissection and development of US-guided technique; phase II: methylene blue (MB) injection; phase III: contrast medium (CM), US-guided injections with computed tomography (CT) control.

ANIMALS

A total of 36 orbits from 18 heads were obtained from 18 dromedary cadavers.

METHODS

Phase I: anatomical dissections were carried out bilaterally, using two heads to determine needle site placement. Phase II: a US-guided, lateral, in-plane approach using one of three volumes of MB (3, 6, or 9 mL) was evaluated in six heads (four orbits per volume tested) to establish the ideal injection volume. Injections of MB that strongly stained all retrobulbar nerves were considered successful, whereas insufficient MB volumes resulted in weak or no nerve staining. Phase III: US-guided retrobulbar injection with CM was carried out using 20 orbits. Computed tomography was performed after each injection trial to determine the accuracy of needle placement and CM dispersal. An injection was judged to be successful when the CT images revealed that the needle was located within the retractor bulbi muscle cone and the CM reached the target nerves at the orbitorotundum and the optic foramina.

RESULTS

Only injection of 9 mL of MB stained the target nerves sufficiently, whereas there was no or only weak staining with 3 and 6 mL, respectively. Therefore, 9 mL of CM was used for the US-guided injections in phase III. Subsequent CT scans revealed satisfying CM distribution within the ocular muscle cone in 18 of 20 cases (90% success rate).

CONCLUSIONS AND CLINICAL RELEVANCE

US-guided retrobulbar injection in dromedary cadavers is feasible. Further research is required to assess its practicality and usefulness in vivo.