Remimazolam Anesthesia for Thyroid Surgery.

Background: Critical upper airway obstruction, hematoma formation, and recurrent laryngeal nerve palsy have been reported as postoperative complications of thyroid surgery. Although remimazolam may reduce the risk of these complications, the efficacy of flumazenil with remimazolam has not been reported. We present the successful anesthesia management of thyroid surgery using remimazolam and flumazenil. Case Presentation. A 72-year-old woman was diagnosed with a goiter and scheduled for a partial thyroidectomy under general anesthesia. We used remimazolam for induction and maintenance using a neural integrity monitor, electromyogram, and endotracheal tube under the bispectral index monitor. At the end of the surgery, spontaneous respiration was confirmed after the intravenous administration of sugammadex, and the patient was extubated under mild sedation. In the operating room, we administered flumazenil intravenously to confirm recurrent laryngeal nerve palsy and active postoperative hemorrhage. The patient was confirmed to have no recurrent laryngeal nerve palsy under full wakefulness but developed active postoperative hemorrhage with normal blood pressure. The patient required reoperation and was reintubated under intravenous administration of propofol. The anesthesia was maintained using 5% of desflurane, and the patient was extubated without any postoperative problems. The anesthesia was then terminated. The patient had no recall of the procedure. Conclusion: Maintenance of general anesthesia using remimazolam allowed the use of a neurostimulator with minimal muscle-relaxant effects, and extubation under sedation reduced the risk of abrupt and unexpected changes in blood pressure, body movement, and coughing. Furthermore, after extubation, the patient was rendered fully awake using flumazenil to confirm the presence of recurrent laryngeal nerve palsy and active postoperative hemorrhage. In addition, the patient had no memory of the reoperation, suggesting that the anterograde amnesic effect of remimazolam had a favorable psychological outcome associated with the reoperation. We safely managed thyroid surgery using remimazolam and flumazenil.

Intraoperative anesthetic management of an infant with a bridging bronchus: A case report.

A newborn infant was diagnosed with an imperforate anus, and colostomy was performed one day after birth. He exhibited repeated episodes of poor oxygenation during intubation, and a CT scan revealed a bridging bronchus. He was scheduled to undergo sacroperineal repair in the prone position 8 months later. A tracheal tube, with its tip modified to widen the opening, was inserted through the nose. This led to normal oxygenation, even while in the prone position. The surgery was completed without any complications.

Abdominal compartment syndrome during hip arthroscopy for an acetabular fracture: a case report.

BACKGROUND: We encountered a case of abdominal compartment syndrome during hip arthroscopic surgery, caused by the irrigation fluid flowing into the peritoneal cavity. CASE PRESENTATION: A 47-year-old male patient with the acetabulum fracture underwent open reduction and internal fixation with hip arthroscopy. Hypothermia, increased airway pressure (under volume-controlled ventilation) and oliguria were observed during the operation, and arterial blood gas analysis showed decreased oxygenation and metabolic acidosis. Abdominal distention was observed, and a postoperative CT revealed accumulation of a large volume of irrigation fluid in the peritoneal cavity and retroperitoneum. The patient was diagnosed as having abdominal compartment syndrome and treated by percutaneous peritoneal drainage. His subsequent course was uneventful, and he was discharged 8 weeks after the operation. Intraperitoneal extravasation of irrigation fluid may occur during hip arthroscopic surgery, and is more likely to occur in the presence of an injury. CONCLUSION: Anesthesiologists should be aware of the possible occurrence of the abdominal compartment syndrome during hip arthroscopic surgery and ensure that it is detected early.

Continuous PECS II block for postoperative analgesia in patients undergoing transapical transcatheter aortic valve implantation.

It has been reported that PECS II block can alleviate postoperative pain following transapical transcatheter aortic valve implantation (TA-TAVI). However, the effectiveness of continuous PECS II block with catheterization has not yet been reported on the postoperative pain in patients undergoing TA-TAVI. We experienced two cases of TA-TAVI who received PECS II block with catheterization to manage postoperative pain. In the first case, a bolus injection for intraoperative pain and subsequent catheterization were performed before the implantation. However, the patient developed severe pain postoperatively in spite of the continuous block due to displacement of the catheter. In the second case, a bolus injection and the catheterization for the continuous block were performed before and after the implantation, respectively, which provided high-quality pain control. Continuous PECS II block may be useful to control perioperative pain associated with TA-TAVI. The insertion of the catheter after the implantation could be useful to avoid its displacement during the surgery.

The Effects of Lidocaine on Central Respiratory Neuron Activity and Nociceptive-Related Responses in the Brainstem-Spinal Cord Preparation of the Newborn Rat.

BACKGROUND: Lidocaine is widely used in the clinical setting as a local anesthetic and antiarrhythmic drug. Although it has been suggested that lidocaine exerts inhibitory effects on the central and peripheral neurons, there are no reports on its effects on central respiratory activity in vertebrates. In this study, we examined the effects of lidocaine on respiratory rhythm generation and nociceptive response in brainstem-spinal cord preparations from the newborn rats. METHODS: Preparations were isolated from Wistar rats (postnatal day 0-3) and superfused with artificial cerebrospinal fluid equilibrated with 95% O2 and 5% CO2, pH 7.4, at 25°C to 26°C. We examined the effects of lidocaine on the fourth cervical ventral root (C4)-inspiratory activity and on the preinspiratory and inspiratory neurons in the rostral medulla. We also examined the effects on the C4/C5 reflex responses induced by ipsilateral C7/C8 dorsal root stimulation, which are thought to be related to the nociceptive response. RESULTS: The application of low doses of lidocaine (10-20 µM) resulted in a slight increase of the C4 burst rate, whereas high doses of lidocaine (100-400 µM) decreased the burst rate in a dose-dependent manner, eventually resulting in the complete cessation of respiratory rhythm. High doses of lidocaine decreased the burst duration and negative slope conductance of preinspiratory neurons, suggesting that lidocaine blocked persistent Na+ current. After the burst generation of the respiratory neurons ceased, depolarizing current stimulation continued to induce action potentials; however, the induction of the spike train was depressed because of strong adaptation. A low dose of lidocaine (20 µM) depressed C4/C5 spinal reflex responses. CONCLUSIONS: Our findings indicate that lidocaine depressed nociception-related responses at lower concentrations than those that induced respiratory depression. Our report provides the basic neuronal mechanisms to support the clinical use of lidocaine, which shows antinociceptive effects with minimal side effects on breathing.