Efficacy and safety of remimazolam besilate for sedation in outpatients undergoing impacted third molar extraction: a prospective exploratory study.

BACKGROUND: Dental treatments often cause anxiety, fear, and stress in patients. Intravenous sedation is widely used to alleviate these concerns, and various agents are employed for sedation. However, it is important to find safer and more effective sedation agents, considering the adverse effects associated with current agents. This study aimed to investigate the efficacy and safety of remimazolam besilate (hereinafter called "remimazolam") and to determine the optimal dosages for sedation in outpatients undergoing dental procedures. METHODS: Thirty-one outpatients aged 18-65 years scheduled for impacted third molar extraction were included in the study. Remimazolam was administered as a single dose of 0.05 mg/kg followed by a continuous infusion at a rate of 0.35 mg/kg/h, with the infusion rate adjusted to maintain a sedation level at a Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score of 2-4. The primary endpoint was the sedation success rate with remimazolam monotherapy, and the secondary endpoints included induction time, recovery time, time until discharge, remimazolam dose, respiratory and circulatory dynamics, and frequency of adverse events. RESULTS: The sedation success rate with remimazolam monotherapy was 100%. The remimazolam induction dose was 0.08 (0.07-0.09) mg/kg, and the anesthesia induction time was 3.2 (2.6-3.9) min. The mean infusion rate of remimazolam during the procedure was 0.40 (0.38-0.42) mg/kg/h. The time from the end of remimazolam administration to awakening was 8.0 (6.7-9.3) min, and the time from the end of remimazolam administration to discharge was 14.0 (12.5-15.5) min. There were no significant respiratory or circulatory effects requiring intervention during sedation. CONCLUSIONS: Continuous intravenous administration of remimazolam can achieve optimal sedation levels without significantly affecting respiratory or circulatory dynamics. The study also provided guidance on the appropriate dosage of remimazolam for achieving moderate sedation during dental procedures. Additionally, the study findings suggest that electroencephalogram monitoring can be a reliable indicator of the level of sedation during dental procedural sedation with remimazolam. TRIAL REGISTRATION: The study was registered in the Japan Registry of Clinical Trials (No. jRCTs061220052) on 30/08/2022.

N-methyl-d-aspartate receptors and glycinergic transmission, respectively, mediate muscle relaxation and immobility of pentobarbital in mice.

Pentobarbital-induced anesthesia is believed to be mediated by enhancement of the inhibitory action of γ-aminobutyric acid (GABA)ergic neurons in the central nervous system. However, it is unclear whether all components of anesthesia induced by pentobarbital, such as muscle relaxation, unconsciousness, and immobility in response to noxious stimuli, are mediated only through GABAergic neurons. Thus, we examined whether the indirect GABA and glycine receptor agonists gabaculine and sarcosine, respectively, the neuronal nicotinic acetylcholine receptor antagonist mecamylamine, or the N-methyl-d-aspartate receptor channel blocker MK-801 could enhance pentobarbital-induced components of anesthesia. Muscle relaxation, unconsciousness, and immobility were evaluated by grip strength, the righting reflex, and loss of movement in response to nociceptive tail clamping, respectively, in mice. Pentobarbital reduced grip strength, impaired the righting reflex, and induced immobility in a dose-dependent manner. The change in each behavior induced by pentobarbital was roughly consistent with that in electroencephalographic power. A low dose of gabaculine, which significantly increased endogenous GABA levels in the central nervous system but had no effect on behaviors alone, potentiated muscle relaxation, unconsciousness, and immobility induced by low pentobarbital doses. A low dose of MK-801 augmented only the masked muscle-relaxing effects of pentobarbital among these components. Sarcosine enhanced only pentobarbital-induced immobility. Conversely, mecamylamine had no effect on any behavior. These findings suggest that each component of anesthesia induced by pentobarbital is mediated through GABAergic neurons and that pentobarbital-induced muscle relaxation and immobility may partially be associated with N-methyl-d-aspartate receptor antagonism and glycinergic neuron activation, respectively.

Analgesia-based Sedation for Oral Surgery in Patients With Chronic Respiratory Obstructive Disease.

Chronic obstructive pulmonary disease (COPD) is a risk factor for postoperative cardiovascular and respiratory complications. Thus, intravenous sedation can be a better option than general anesthesia for surgery in patients with severe COPD. Herein, we present 2 cases of analgesia-based sedation in patients with severe COPD who underwent oral surgery. The current study aimed to discuss these cases to provide knowledge about the appropriate sedation management in patients with this disease. In the current cases, the patients received sufficient analgesia and minimum sedation (analgesia-based sedation). Moreover, dexmedetomidine was used for maintaining sedation and fentanyl for analgesic effects. Furthermore, we focused on providing the maximum analgesic effect of local anesthesia. The patients' vital signs were stable. They did not have any psychological or physical complaints, such as anxiety and pain, during the procedure. Then, they were discharged from the hospital without any complications. Thus, analgesia-based sedation can be an alternative option for oral surgery in patients with COPD.

Difficult intubation and postoperative aspiration pneumonia associated with Moebius syndrome: a case report.

BACKGROUND: Moebius syndrome is a rare congenital disorder characterized by non-progressive palsy of the abducens (VI) and facial (VII) cranial nerves. Its common features include dysfunctions associated with other cranial nerves, orofacial abnormalities, skeletal muscle hypotonia, and other systemic disorders of differing severities. There are several concerns in the perioperative management of patients with Moebius syndrome. CASE PRESENTATION: We present a report on the management of general anesthesia of a 14-year-old male patient with Moebius syndrome who was scheduled for mandibular cystectomy. The patient was diagnosed with Moebius syndrome at the age of 7 years based on his clinical manifestations of nerve palsy since birth and cranial nerve palsy of the trigeminal (V), facial (VII), glossopharyngeal (IX), vagus (X), and sublingual nerves (XII). The patient's oral morphological abnormalities made intubation difficult. He also experienced dysphagia and aspiration pneumonia on a daily basis. Oral secretions were frequently suctioned postoperatively. However, after discharge, the patient developed aspiration pneumonia and was readmitted to the hospital. CONCLUSIONS: The main problem arising when administering general anesthesia to patients with this syndrome is difficult airway management. The oral abnormalities in these patients, such as small jaw and extreme dental stenosis, make mask ventilation and intubation difficult. Furthermore, this syndrome often involves respiratory impairment and dysphagia due to cerebral nerve palsy, so there is a high risk of postoperative respiratory complications. Since multiple organs are affected in patients with Moebius syndrome, appropriate perioperative management strategies must be prepared for these patients.

Pentobarbital may protect against neurogenic inflammation after surgery via inhibition of substance P release from peripheral nerves of rats.

The inflammatory response related to surgery is considered surgical inflammation. Most anesthetic agents directly or indirectly suppress the immune response. However, the intravenous anesthetics pentobarbital and ketamine were reported to inhibit the lipopolysaccharide-induced inflammatory response such as cytokines formation. Neurogenic inflammation is inflammation originating from the local release of inflammatory mediators, such as substance P (SP), by primary afferent neurons after noxious stimuli like surgery. Thus, in this study, we examined whether pentobarbital and ketamine suppress SP release from cultured dorsal root ganglion (DRG) neurons. DRG cells were dissected from male Wistar rats. Released SP was measured by radioimmunoassay. We demonstrated that higher concentrations of pentobarbital (100-1,000 µM) significantly inhibited capsaicin (100 nM)-induced, but not high K+ (50 mM)-induced, SP release from DRG cells, although a high concentration of ketamine (1 mM) did not. This study revealed that pentobarbital functions between the activation of vanilloid receptor subtype 1 (TRPV1) receptors, to which capsaicin selectively binds, and the opening of voltage-operated Ca2+ channels (VOCC) in the nerve endings. Therefore, the anti-inflammatory action of pentobarbital is mediated through different mechanisms than those of ketamine. Thus, the inhibitory effect of pentobarbital on SP release from peripheral terminals may protect against neurogenic inflammation after surgery.

Efficacy of Chest Compressions Performed on Patients in Dental Chairs Versus on the Floor.

This study aimed to investigate the characteristics of chest compressions performed in dental chairs (DCs) with 2 different structural support designs and on the floor. This randomized prospective study was conducted to compare the effectiveness of chest compressions (rate and depth) using a feedback device and a manikin reporting system. The mean anterior chest wall motion measurements captured using the feedback device were significantly increased in the DCs than on the floor, whereas the percentage of net chest compression depths ≥5 cm as measured using the manikin reporting system were significantly decreased in the DCs than on the floor. These findings suggest that cardiopulmonary resuscitation performed in a DC without the use of a supporting stool or stiff backboard is not likely to be effective even if a DC design that incorporates a supportive steel column is utilized.

Usefulness of Tranexamic Acid Administration During Sagittal Split Ramus Osteotomy.

ABSTRACT: Tranexamic acid has been used to reduce intraoperative bleeding; however, its effect on anti-inflammation and the amount of drainage after orthognathic surgery is yet to be determined. Therefore, we aimed to examine the effect of tranexamic acid on intraoperative bleeding volume and operation time, amount of drainage, and anti-inflammation after orthognathic surgery. Forty healthy women who underwent bilateral sagittal split ramus osteotomy under general anesthesia participated in this study. The amount of intraoperative bleeding, the operation time, the amount of drainage, and the C-reactive protein level were compared between patients intravenously administered with tranexamic acid before surgery (before-surgery group) and those administered with the drug after surgery (after-surgery group). All data were analyzed using the Student t-test. Results were considered to be statistically significant when P < 0.05. Although no significant difference was found in the amount of drainage between the groups (P > 0.05), significant variations were detected in the amount of bleeding during surgery (before-surgery group: 161.7 ±â€Š45.3 mL versus after-surgery group: 270.2 ±â€Š24.0 mL; P = 0.0009), operation time (before-surgery group: 141.3 ±â€Š16.8 min versus after-surgery group: 166.8 ±â€Š24.9 min; P = 0.03), and postoperative C-reactive protein level (before-surgery group: 3.77 ±â€Š0.40 mg/dL versus after-surgery group: 5.02 ±â€Š0.75 mg/dL; P = 0.012) between the groups. In conclusion, administering tranexamic acid before surgery was found to significantly decrease bleeding, reduce operation time, and suppress postoperative inflammation.

The indirect γ-aminobutyric acid (GABA) receptor agonist gabaculine-induced loss of the righting reflex may inhibit the descending analgesic pathway.

In the spinal cord, γ-aminobutyric acid (GABA) interneurons play an essential role in antinociception. However, not all actions of GABA favor antinociception at the supraspinal level. We previously reported that gabaculine, which increases endogenous GABA in the synaptic clefts, induces loss of the righting reflex (LORR) that is one indicator of hypnosis, but not immobility in response to noxious stimulus. A slow pain is transmitted to the spinal cord via C fibers and evokes substance P (SP) release from their terminals. However, the antinociceptive effects of gabaculine are still unknown. Our study examined whether the analgesic effects of the opioid morphine or the α2-adrenoceptor agonist dexmedetomidine, whose actions are mediated through facilitation of the descending analgesic pathway, are affected by gabaculine-induced LORR. We also explored the effects of GABA receptor agonists on SP release from cultured dorsal root ganglion (DRG) neurons. All drugs were administered systemically to mice. To assess antinociception, loss of nociceptive response (analgesia) and immobility were evaluated. DRG cells were dissected from rats. Gabaculine produced no analgesia. Either morphine or dexmedetomidine in combination with gabaculine induced immobility; however, the doses of each drug required to induce immobility were much higher than those required to induce analgesia. Capsaicin significantly increased SP release from DRG cells, but a high concentration (1 mM) of the GABA receptor agonist muscimol, propofol, gaboxadol, or baclofen did not inhibit the capsaicin-induced SP release, suggesting that their antinociceptive effects were not through this mechanism. Thus, the gabaculine-induced LORR may inhibit the descending analgesic pathway.

Effective Postoperative Analgesia Using Intravenous Flurbiprofen and Acetaminophen.

PURPOSE: Management of postoperative pain is one of the most important components in postoperative care, because most patients have pain after dental surgery. The aim of this study was to evaluate whether acetaminophen could be an alternative to fentanyl in combination with a nonsteroidal anti-inflammatory drug (NSAID) as an analgesic after dental surgery in cases in which narcotic drugs were contraindicated. MATERIALS AND METHODS: Patients were 24- to 54-year-old men who underwent enucleation of a mandibular cyst under general anesthesia. The authors measured time from discontinuation of anesthetic administration until discharge from the operating room and postoperative pain during 4 hours after discharge. They compared these parameters between patients who were intravenously administered an NSAID such as flurbiprofen with fentanyl (NSAID/fentanyl group) and those administered an NSAID with acetaminophen (NSAID/acetaminophen group). Parametric data of time were analyzed using Student t test. Nonparametric data of the analgesic effect were analyzed using Mann-Whitney U test. RESULTS: Time until discharge from the operating room after discontinuation of anesthetics in the NSAID/fentanyl group was significantly longer than that in the NSAID/acetaminophen group (P < .05). In contrast, there was no significant difference in analgesic effect between the NSAID/acetaminophen and NSAID/fentanyl groups (P > .05). CONCLUSION: Although recovery time in the operating room of the flurbiprofen and acetaminophen group was markedly shorter than that of the flurbiprofen and fentanyl group, the postoperative analgesic effects of the 2 drugs were equipotent. Therefore, acetaminophen can be an alternative to fentanyl in cases in which narcotic drugs are contraindicated.

A Case With Deteriorating Palmoplantar Pustulosis and Hyperthyroidism After Simultaneous Bimaxillary Orthognathic Surgery.

A case of palmoplantar pustulosis and hyperthyroidism following orthognathic surgery is presented. Both diseases may have been related to allergic phenomena.