A Case Report of Burning Mouth Syndrome with Dry Mouth Managed by Kampo Medicine.

The patient was a 56-year-old woman who complained of chronic pain involving her tongue. We diagnosed her with burning mouth syndrome (BMS) based on exclusion of any local factors or systemic conditions. The patient not only had tongue pain but also had other signs and symptoms like scalloped tongue, dry mouth, and headache. To manage these additional issues, we used Goreisan, an herbal Kampo medicine, as a complementary alternative medicine (CAM) approach along with cognitive behavioral therapy (CBT). The patient's BMS was successfully managed with the combination of CAM and CBT, which may suggest that the pathophysiology for BMS might be nociplastic pain rather than purely nociceptive or neuropathic.

Examination of stabilization of sedation by Nasal High Flow in patients with endoscopic retrograde cholangiopancreatography during sedation using Dexmedetomidine.

INTRODUCTION: Dexmedetomidine is used for the sedation method in the case of endoscopic retrograde cholangiopancreatography (ERCP) for the purpose of relieving patient anxiety. It has been reported that CO2 accumulated during sedation causes an arousal reaction, so how to normalize CO2 during sedation can be improved by administration of the minimum necessary sedative.Nasal High Flow oxygen therapy (NHF) uses a mild positive pressure load that improves carbon dioxide washout and reduces rebreathing to improve respiratory function and therefore is widely used to prevent hypoxemia and hypercapnia. In this study, we will investigate whether the upper airway patency would be maintained and the hypercapnia and hypoxemia during sedation would be prevented, by applying NHF as a respiratory management method to patients undergoing ERCP under sedation. METHODS/DESIGN: In a randomized comparative study of 2 groups, the NHF device use group and the nasal cannula use group, for adult patients who visited the Nagasaki University Hospital and underwent ERCP examination under sedation. For sedation, Dexmedetomidine will be used in combination with and Midazolam and evaluation by anesthesiologist. In addition, as an analgesic, pethidine hydrochloride was administered intravenously. The total dose of the analgesic pethidine hydrochloride used in combination is used as the primary endpoint. As a secondary evaluation item, the percutaneous CO2 concentration is evaluated with a TCO2 monitor to examine whether it is effective in preventing hypercapnia. Furthermore, we will evaluate the incidence of hypoxemia with a percutaneous oxygen saturation value of 90% or less, and examine whether the use of equipment is effective in preventing the occurrence of hypercapnia and hypoxemia. DISCUSSION: The purpose of this study was to obtain evidence for the utility of NHF as a potential therapeutic device for patients undergoing an ERCP under sedation, assessed by determining if the incidence rates of hypercapnia and hypoxemia decreased in the NHF device group, compared to the control group that did not use of this device.

Respiratory support with nasal high flow without supplemental oxygen in patients undergoing endoscopic retrograde cholangiopancreatography under moderate sedation: a prospective, randomized, single-center clinical trial.

BACKGROUND: Nasal high flow (NHF) may reduce hypoxia and hypercapnia during an endoscopic retrograde cholangiopancreatography (ERCP) procedure under sedation. The authors tested a hypothesis that NHF with room air during ERCP may prevent intraoperative hypercapnia and hypoxemia. METHODS: In the prospective, open-label, single-center, clinical trial, 75 patients undergoing ERCP performed with moderate sedation were randomized to receive NHF with room air (40 to 60 L/min, n = 37) or low-flow O2 via a nasal cannula (1 to 2 L/min, n = 38) during the procedure. Transcutaneous CO2, peripheral arterial O2 saturation, a dose of administered sedative and analgesics were measured. RESULTS: The primary outcome was the incidence of marked hypercapnia during an ERCP procedure under sedation observed in 1 patient (2.7%) in the NHF group and in 7 patients (18.4%) in the LFO group; statistical significance was found in the risk difference (-15.7%, 95% CI -29.1 - -2.4, p = 0.021) but not in the risk ratio (0.15, 95% CI 0.02 - 1.13, p = 0.066). In secondary outcome analysis, the mean time-weighted total PtcCO2 was 47.2 mmHg in the NHF group and 48.2 mmHg in the LFO group, with no significant difference (-0.97, 95% CI -3.35 - 1.41, p = 0.421). The duration of hypercapnia did not differ markedly between the two groups either [median (range) in the NHF group: 7 (0 - 99); median (range) in the LFO group: 14.5 (0 - 206); p = 0.313] and the occurrence of hypoxemia during an ERCP procedure under sedation was observed in 3 patients (8.1%) in the NHF group and 2 patients (5.3%) in the LFO group, with no significant difference (p = 0.674). CONCLUSIONS: Respiratory support by NHF with room air did not reduce marked hypercapnia during ERCP under sedation relative to LFO. There was no significant difference in the occurrence of hypoxemia between the groups that may indicate an improvement of gas exchanges by NHF. TRIAL REGISTRATION: jRCTs072190021 . The full date of first registration on jRCT: August 26, 2019.

Influence of general anesthesia on the postoperative sleep cycle in patients undergoing surgery and dental treatment: a scoping review on the incidence of postoperative sleep disturbance.

General anesthesia may influence the postoperative sleep cycle; however, no clinical studies have fully evaluated whether anesthesia causes sleep disturbances during the postoperative period. In this scoping review, we explored the changes in postoperative sleep cycles during surgical procedures or dental treatment under general anesthesia. We compared and evaluated the influence of general anesthesia on sleep cycles and sleep disturbances during the postoperative period in adult and pediatric patients undergoing surgery and/or dental treatment. Literature was retrieved by searching eight public databases. Randomized clinical trials, observational studies, observational case-control studies, and cohort studies were included. Primary outcomes included the incidence of sleep, circadian cycle alterations, and/or sleep disturbances. The search strategy yielded six studies after duplicates were removed. Finally, six clinical trials with 1,044 patients were included. In conclusion, general anesthesia may cause sleep disturbances based on alterations in sleep or the circadian cycle in the postoperative period in patients scheduled for elective surgery.

Safety of COVID-19 vaccine delivery by dentists: An observational cohort study.

Background/purpose: Although many coronavirus disease 2019 (COVID-19) vaccine injections have been administered worldwide, the safety of this practice remains unclear. This study aimed to compare the rates of complications associated with COVID-19 vaccines administered by dentists with those of vaccines administered by nurses. This study aimed to evaluate the safety of a vaccination program delivered by dentists. Materials and methods: This observational cohort study included 537 recipients of the second dose of the Pfizer COVID-19 vaccine, delivered as an intramuscular injection to the upper arm deltoid muscle by dentists or nurses at the study site. Vaccine recipients were divided into two groups according to the vaccination administrator (dentist vs. nurse groups). The rates of complications associated with intramuscular injection technique (numbness in the hand or arm at the time of the injection, vasovagal reflex at the time of the injection, vaccine-related shoulder injury, and prolonged numbness) were examined. Results: A total of 125 vaccine recipients were included (nurse group, n = 84; dentist group, n = 41). The overall incidence rate of complications was lower in the dentist group (2.4%; 1/41) than in the nurse group (8.3%; 7/84). However, this difference was not statistically significant (P = 0.3). Conclusion: This study suggests that the safety of COVID-19 vaccine administration is comparable between dentists and nurses.

The Impact of COVID-19 on Dental Anesthesiologists: An Online Survey of Board-Certified Dental Anesthesiology Specialists of the Japanese Dental Society of Anesthesiology.

OBJECTIVE: The impact of the COVID-19 pandemic on dental anesthesiologists has not been examined. This study aimed to determine how the COVID-19 pandemic affected Japanese dental anesthesiologists' professional lives. METHODS: An online questionnaire related to the effects of COVID-19 on dental anesthesiologists' professional lives was emailed to 351 board-certified dental anesthesiology specialists from the Japanese Dental Society of Anesthesiology. The endpoints of this study were changes in income and job satisfaction as a dental anesthesiologist from 2019 prior to the COVID-19 pandemic. RESULTS: A total of 141 dental anesthesiologists participated in the survey. Most respondents reported no change in income relative to 2019 for 2020 or 2021. Significantly more dental anesthesiologists reported income decreases relative to 2019 for 2020 (39%) vs 2021 (21.3%; P = .001). Very few dental anesthesiologists reported income increases relative to 2019 for 2020 (2.1%) vs 2021 (15.6%; P < .001). Job satisfaction as a dental anesthesiologist remained unchanged for all 3 years. CONCLUSION: Even though many Japanese dental anesthesiologist specialists lost income because of COVID-19, they maintained their job satisfaction.

The clinical advantage of nasal high-flow in respiratory management during procedural sedation: A scoping review on the application of nasal high-flow during dental procedures with sedation.

Structured summary: Rationale: Nasal high-flow (NHF), a new method for respiratory management during procedural sedation, has greater advantages than conventional nasal therapy with oxygen. However, its clinical relevance for patients undergoing oral maxillofacial surgery and/or dental treatment remains uncertain and controversial, due to a paucity of studies. This scoping review compared and evaluated NHF and conventional nasal therapy with oxygen in patients undergoing oral maxillofacial surgery and/or dental treatment. Materials and methods: A literature search of two public electronic databases was conducted, and English writing randomized controlled trials (RCTs) of nasal high flow during dental procedure with sedation reviewed. The primary and secondary outcomes of interest were the incidence of hypoxemia and hypercapnia during sedation and the need for intervention to relieve upper airway obstruction, respectively. Results: The search strategy yielded 7 studies, of which three RCTs met our eligibility criteria, with a total of 78 patients. Compared with conventional nasal therapy with oxygen, NHF significantly reduced the incidence of hypoxemia and hypercapnia during procedural sedation. Conclusion: NHF can maintain oxygenation and possibly prevent hypercapnia in patients undergoing dental treatment. Additional RCTs are needed to clarify and confirm these findings.

Involvement of spinal G-protein inwardly rectifying potassium (GIRK) channels in the enhanced antinociceptive effects of the activation of both µ-opioid and cannabinoid CB1 receptors.

Neuropathic pain is refractory to opioid analgesics. Since there are functional linkages between µ-opioid receptors (MOR) and cannabinoid receptors (CBR), the present study was designed to investigate the interactions between MOR and CB1R based on antinociceptive effects for neuropathic pain mediated through G protein-coupled inwardly-rectifying potassium channels (GIRKs). The antinociceptive effects against pseudonociceptive response or neuropathic pain of MOR and CBR agonists were assessed in mice with or without partial sciatic nerve ligation. To investigate the functional interaction between MOR and CB1R, electrophysiological recording through GIRK was performed using the two-electrode voltage-clamp method in oocytes along with Western blotting in the spinal cord of mice. Co-administration of the MOR agonist DAMGO and the CB1R agonist CP55,940 augmented inwardly rectifying K+ currents in Xenopus oocytes co-expressing MOR, CB1R and GIRK1/2. Further, combination of morphine and the CBR agonist WIN-55,212-2 produced prominent antinociceptive effects in an i.t. GIRK1 inhibitor-reversible manner. Furthermore, CB1R was upregulated under neuropathic pain in the spinal cord, and such upregulation and antinociceptive effects were not altered by repeated treatment with morphine plus WIN-55,212-2. Our findings suggest that co-administration of MOR and CBR agonists could enhance their antinociceptive effects through GIRK1 in the spinal cord of mice.

Dental treatment under intravenous sedation prolongs longevity of a fixed prosthesis in patients with intellectual disabilities.

AIMS: This study aimed to assess the longevity of a fixed prosthesis in patients with intellectual disability (ID) and to investigate the risk factors associated with the failure of a prosthesis due to abutment tooth extraction or prosthesis dislodgement or removal. METHODS: We studied past medical records to evaluate the longevity of 315 prostheses that were luted in 76 patients with ID. We calculated the survival rates and assessed 15 variables potentially associated with prosthetic failure using multivariate Cox regression analyses with shared frailty for patients. RESULTS: Three-quarters of our sample population had severe or profound ID. The maximum observation period was 31.0 years, and the corresponding survival ratio was 32.5%; the survival ratio at 10 years was 59.4%. The use of intravenous sedation significantly influenced the success of the prosthesis, with the hazard ratio (HR) being 0.49 times that of conventional treatment without behavior-altering drug therapy. The most significant risk factor for prosthetic failure was age at placement; the HR for patients aged ≥31 years was 2.82 times that for patients aged ≤ 20 years. CONCLUSIONS: In patients with severe ID, appropriate intravenous sedation was effective in prolonging the longevity of a fixed prosthesis.

Study on the preventive effect of ramelteon on the onset of sleep disorder after general anesthesia in patients with autism spectrum disorder: A study protocol.

BACKGROUND: The persistent loss of consciousness caused by general anesthesia without the existence of repeated 90-minute cycles of non-REM and REM sleep might significantly disturb and suppress the cycle of normal physiological sleep in postoperative periods after general anesthesia. Patients with autism spectrum disorders (ASD) with existing circadian rhythm disorder are reported to rapidly deteriorate due to acute sleep disorder during the perioperative period after general anesthesia.A melatonin receptor agonist, ramelteon (Rozerem), which is a sleep cycle regulator, is used as a therapeutic drug for patients with sleep disorders, but there are no studies on the prevention of postoperative sleep disorder after general anesthesia.In this study, we investigate whether prophylactic administration of a sleep-inducing substance, a melatonin receptor agonist, is effective against sleep disorder after general anesthesia in patients with ASD. METHODS/DESIGN: This study is intended for patients with ASD aged 12 years and above who undergo treatment at Nagasaki University Hospital, Isahaya General Hospital Dentistry, and Sasebo City General Medical Center Dentistry and undergo dental treatment under general anesthesia. A melatonin receptor agonist (Rozerem) will be taken 7 days prior and 7 days postsurgery in patients diagnosed with insomnia. A randomized comparison will be made between 2 groups: an experimental group that is additionally administered Rozerem and a control group.The primary endpoint is the incidence of NREM-REM sleep disorders that occur within 3 to 5 days after general anesthesia. The secondary endpoint is the incidence of circadian rhythm sleep disorders (rate of occurrence of sleep-retardation syndrome with drowsiness and strong fatigue). DISCUSSION: Postoperative sleep disorders after general anesthesia has been reported in patients with ASD; however, effective preventive pharmacological treatments have not been established. A sleep cycle regulator, ramelteon (Rozerem), is used as a therapeutic drug for patients with sleep disorders by decreasing the difficulty of falling asleep in insomnia. If sleep disorder can be prevented after the administration of general anesthesia in patients with ASD, we can support social participation while maintaining their quality of life. TRIAL REGISTRATION: The study was registered with the jRCT1071200030.

Successful Dental Treatments Using Procaine Hydrochloride in a Patient Afraid of Local Anesthesia but Consenting for Allergic Testing with Lidocaine: A Case Report.

BACKGROUND: We report a case in which effective dental anesthetic management was achieved using procaine hydrochloride for a patient who had an unknown history of allergic reactions to lidocaine. CASE PRESENTATION: Because the patient refused to undergo screening tests using any of the amide-type local anesthetics because of her extreme fear against local anesthetics that she had been administered previously, procaine hydrochloride, which is an ester-form local anesthetic, was the only agent to be tested on this patient at the department of dermatology. Consequent to a negative allergy test, we performed complete dental treatment using procaine hydrochloride after additional chairside drug challenge tests using minimum test dose under vital sign monitoring. CONCLUSION: The success of dental treatment using procaine hydrochloride may have relieved the patient's fear of local anesthesia. We discuss an important aspect of treatment planning for patients with a history of complications during local anesthesia.

Efficacy of nasal high flow therapy on the coordination between breathing and swallowing of saliva during daytime nap in chronic obstructive pulmonary disease patients: A single center, randomized crossover controlled study.

BACKGROUND: There are some clinical reports on dysphagia in patients with chronic obstructive pulmonary disease (COPD); however, its pathophysiology remains largely unknown.Changes in respiratory function occur in patients with COPD causing a decrease in tidal volume and an increase in respiratory rate (tachypnea). In addition, it leads to lack of coordination between respiration and swallowing.A new treatment called nasal high flow (NHF) has been introduced for patients with COPD, replacing the traditional non-invasive ventilation (NIV) procedure. The NHF therapy involves inhalation of high flow of humidified air, which reduces respiratory effort in patients with COPD. Furthermore, NHF therapy facilitates swallowing of saliva even during respiratory management. A recent clinical study reported that high-flow nasal cannula oxygen therapy for 6 weeks improved the health-related quality of life and reduced hypercapnia in patients with stable COPD. Taken together, NHF therapy is gaining attention in the clinical management of patients with COPD.Therefore, in this study, we aim to examine the efficacy of NHF therapy on the coordination between breathing and swallowing of saliva during daytime nap in patients with COPD. METHODS/DESIGN: This open-label, investigator-initiated, single center study will evaluate the efficacy of NHF therapy on the coordination between breathing and swallowing of saliva during the daytime nap in COPD patients with forced expiratory volume in 1 second (FEV1%) of <70% during treatment at the Nagasaki University Hospital Respiratory Rehabilitation Center. Evaluations will be performed during the 90 to 180 minute "daytime nap" in the measurement room of the hospital. The primary endpoint will be the rate of appearance of the expiratory phase after swallowing of saliva and the frequency of swallowing during the measurement period. DISCUSSION: The purpose of this study is to obtain evidence regarding the utility of NHF as a potential therapeutic device for COPD patients to prevent aspiration of saliva during the sleep stage of daytime nap. The utility will be assessed by comparing the decrease in incidence rates of the expiratory phase after swallowing of saliva in the NHF device group and the control group, wherein this device was not used.

A study on respiratory management in acute postoperative period by nasal high flow for patients undergoing surgery under general anesthesia.

In head and neck surgery where the oropharyngeal area is the operative field, postoperative respiratory depression and upper airway obstruction are common. Therefore, supplemental oxygen is administered to prevent severe postoperative early hypoxemia. However, a high concentration of oxygen increases the likelihood of secondary complications, such as carbon dioxide (CO2) narcosis. Nasal high-flow (NHF) therapy generates high flows (≤60 L/min) of heated and humidified gas delivered via nasal cannula and provides respiratory support by generating positive airway pressure, clearance of dead space and reduction of work of breathing. This study aims to determine whether the postoperative hypoxemia and hypercapnia can be prevented by NHF without the requirement of supplemental oxygen. The study will recruit adult patients undergoing planned oral surgery under general anesthesia at Nagasaki University Hospital. It is a randomized parallel group comparative study with 3 groups: NHF with room air only and no supplemental oxygen, no respiratory support, and face mask oxygen administration. The study protocol will begin at the time that the patient is returned to the general ward and will finish 3 hours later. The primary endpoint is the time-weighted average of transcutaneous O2 over the 180 minutes and secondary endpoints are the time-weighted average of transcutaneous CO2 (tcpCO2), SpO2, and respiratory rate, incidence rate of marked hypercapnia (tcpCO2 ≥60 mm Hg for 5 minutes or longer), incidence rate of moderate hypercapnia (tcpCO2 ≥50 mm Hg for 5 minutes or longer) and the percentage of time that SpO2 is <90%. Included also is a group in which the postoperative management is performed only by spontaneous breathing without performing respiratory support such as oxygen administration, to investigate the efficacy and necessity of conventional oxygen administration. This exploratory study will investigate the use of NHF without supplemental oxygen as an effective respiratory support during the acute postoperative period. TRIAL REGISTRATION:: The study was registered the jRCTs072200018. URL https://jrct.niph.go.jp/latest-detail/jRCTs072200018.

Study on prevention of hypercapnia by nasal high flow in patients undergoing endoscopic retrograde cholangiopancreatography during intravenous anesthesia.

BACKGROUND: For relatively invasive upper gastrointestinal endoscopy procedures, such as an endoscopic retrograde cholangiopancreatography (ERCP), and also lower gastrointestinal endoscopy procedures, intravenous anesthesia is routinely used to reduce patient anxiety. However, with the use of intravenous anesthesia, even at mild to moderate depth of anesthesia, there is always a risk of upper airway obstruction due to a relaxation of the upper airway muscles.With the advent of nasal high flow (NHF) devices that allow humidified high flow air through the nasal cavity, can be used as a respiratory management method in the context of anesthesia. AIRVO is commonly used for patients with obstructive sleep apnea and other respiratory disorders. This device uses a mild positive pressure load (several cmH2O) that improves carbon dioxide (CO2) washout and reduces rebreathing to improve respiratory function and therefore is widely used to prevent hypoxemia and hypercapnia.This study aims to maintain upper airway patency by applying NHF with air (AIRVO) as a respiratory management method during intravenous anesthesia for patients undergoing an ERCP. In addition, this study investigates whether the use of an NHF device in this context can prevent intraoperative hypercapnia and hypoxemia. METHODS/DESIGN: This study design employed 2 groups of subjects. Both received intravenous anesthesia while undergoing an ERCP, and 1 group also used a concurrent nasal cannula NHF device. Here we examine if the use of an NHF device during intravenous anesthesia can prevent hypoxemia and hypercapnia, which could translate to improved anesthesia management.Efficacy endpoints were assessed using a transcutaneous CO2 monitor (TCM). This device measured the changes in CO2 concentration during treatment. Transcutaneous CO2 (PtcCO2) concentrations of 60 mm Hg or more (PaCO2 > 55 mm Hg) were considered marked hypercapnia. PtcCO2 concentrations of 50 to 60 mm Hg or more (equivalent to PaCO2 > 45 mm Hg) were considered moderate hypercapnia.Furthermore, the incidence of hypoxemia with a transcutaneous oxygen saturation value of 90% or less, and whether the use of NHF was effective in preventing this adverse clinical event were evaluated. DISCUSSION: The purpose of this study was to obtain evidence for the utility of NHF as a potential therapeutic device for patients undergoing an ERCP under sedation, assessed by determining if the incidence rates of hypercapnia and hypoxemia decreased in the NHF device group, compared to the control group that did not use this device. TRIAL REGISTRATION: The study was registered in the jRCTs 072190021.URL https://jrct.niph.go.jp/en-latest-detail/jRCTs072190021.

Study on prevention of hypercapnia by Nasal High Flow in patients with endoscopic submucosal dissection during intravenous anesthesia.

BACKGROUND: For relatively invasive upper gastrointestinal endoscopy procedures, such as an endoscopic submucosal dissection (ESD), intravenous anesthesia is routinely used to reduce patient anxiety. However, with the use of intravenous sedation, even at mild to moderate depth of anesthesia, there is always a risk of upper airway obstruction due to a relaxation of the upper airway muscles.With the advent of Nasal High Flow (NHF) devices that allow humidified high flow air through the nasal cavity, can be used as a respiratory management method in the context of anesthesia. AIRVO is commonly used for patients with obstructive sleep apnea and other respiratory disorders. This device uses a mild positive pressure load (several cmH2O) that improves carbon dioxide (CO2) washout and reduces rebreathing to improve respiratory function and therefore is widely used to prevent hypoxemia and hypercapnia.This study aims to maintain upper airway patency by applying NHF with air (AIRVO) as a respiratory management method during intravenous anesthesia for patients undergoing an ESD. In addition, this study investigates whether the use of an NHF device in this context can prevent intraoperative hypercapnia and hypoxemia. METHODS/DESIGN: This study design employed 2 groups of subjects. Both received intravenous anesthesia while undergoing an ESD, and 1 group also used a concurrent nasal cannula NHF device. Here we examine if the use of an NHF device during intravenous anesthesia can prevent hypoxemia and hypercapnia, which could translate to improved anesthesia management.Efficacy endpoints were assessed using a transcutaneous CO2 monitor. This device measured the changes in CO2 concentration during treatment. Transcutaneous CO2 (PtcCO2) concentrations of 60 mmHg or more (PaCO2 > 55 mmHg) were considered marked hypercapnia. PtcCO2 concentrations of 50 to 60 mmHg or more (equivalent to PaCO2 > 45 mmHg) were considered moderate hypercapnia.Furthermore, the incidence of hypoxemia with a transcutaneous oxygen saturation value of 90% or less, and whether the use of NHF was effective in preventing this adverse clinical event were evaluated. DISCUSSION: The purpose of this study was to obtain evidence for the utility of NHF as a potential therapeutic device for patients undergoing an ESD under anesthesia, assessed by determining if the incidence rates of hypercapnia and hypoxemia decreased in the NHF device group, compared to the control group that did not use of this device. TRIAL REGISTRATION: The study was registered the jRCTs 072190022.URL https://jrct.niph.go.jp/en-latest-detail/jRCTs072190022.

Upper-airway collapsibility and compensatory responses under moderate sedation with ketamine, dexmedetomidine, and propofol in healthy volunteers.

BACKGROUND: Ketamine is a potent sedative drug that helps to maintain upper-airway patency, due to its higher upper-airway dilator muscular activity and higher level of duty cycle, as seen in rats. However, no clinical trials have tested passive upper-airway collapsibility and changes in the inspiratory duty cycle against partial upper-airway obstruction in humans. The present study evaluated both the passive mechanical upper-airway collapsibility and compensatory response against acute partial upper-airway obstruction using three different sedative drugs in a crossover trial. METHODS: Eight male volunteers entered this nonblinded, randomized crossover study. Upper-airway collapsibility (passive critical closing pressure) and inspiratory duty cycle were measured under moderate sedation with ketamine, propofol, and dexmedetomidine. Propofol, dexmedetomidine, and ketamine anesthesia were induced to obtain adequate, same-level sedation, with a BIS value of 50-70 and the OAA/S score of 2-3 and RASS score of -3. RESULTS: The median passive critical closing pressure of 0.08 [-5.51 to 1.20] cm H2 O was not significantly different compared to that of propofol sedation (-0.32 [-1.41 to -0.19] cm H2 O) and of dexmedetomidine sedation (-0.28 [-0.95 to -0.03] cm H2 O) (p = .045). The median passive RUS for ketamine 54.35 [32.00 to 117.50] cm H2 O/L/s was significantly higher than that for propofol 5.50 [2.475 to 19.60] cm H2 O/L/s; (mean difference, 27.50; 95% CI 9.17 to 45.83) (p = .009) and for dexmedetomidine 19.25 [4.125 to 22.05] cm H2 O/L/s; (mean difference, 22.88; 95% CI 4.67 to 41.09) (p = .021). The inspiratory duty cycle increased significantly as the inspiratory airflow decreased in passive conditions for each sedative drug, but behavior differed among the three sedative drugs. CONCLUSION: Our findings demonstrate that ketamine sedation may have an advantage of both maintained passive upper-airway collapsibility and a compensatory respiratory response, due to both increase in neuromuscular activity and the increased duty cycle, to acute partial upper-airway obstruction.

Nasal high flow improves ventilation during propofol sedation: A randomized cross-over study in healthy volunteers.

OBJECTIVE: Hypoventilation and carbon dioxide (CO2) retention are common during sedation. The current study investigated the ventilation responses to nasal high flow (NHF) during sedation with propofol. METHODS: NHF of 30 L/min and 60 L/min with room air was applied during wakefulness and sedation in 10 male volunteers. Ventilation was monitored by respiratory inductance plethysmography, transcutaneous partial pressure of CO2 (TcCO2), and SpO2. RESULTS: During sedation, NHF of 30 L/min and 60 L/min reduced the TcCO2 by 2.9 ± 2.7 mmHg (p = 0.025) and by 3.6 ± 3.4 mmHg (p = 0.024) without affecting SpO2 and reduced the mean respiratory rate by 3 ± 3 breaths/min (p = 0.011) and by 4 ± 3 breaths/min (p = 0.003), respectively. CONCLUSION: During sedation with propofol, NHF without supplemental oxygen attenuated CO2 retention and reduced the respiratory rate. The findings show that NHF can improve ventilation during sedation, which may reduce the risk of complications related to hypoventilation.

The effect of midazolam administration for the prevention of emergence agitation in pediatric patients with extreme fear and non-cooperation undergoing dental treatment under sevoflurane anesthesia, a double-blind, randomized study.

Background: Sevoflurane is generally the preferred anesthetic agent for general anesthesia in pediatric patients, due to its rapid induction and recovery characteristics. However, it has been recognized that a major complication is emergence agitation when awakening from general anesthesia. The aim of this study was to evaluate the occurrence rate of emergence agitation in the operating room and postoperative recovery area following intraoperative administration of midazolam to pediatric patients under general anesthesia. Patients and methods: One hundred and twenty pediatric patients undergoing dental treatment under sevoflurane anesthesia were enrolled in this study. The patients were divided into three groups (n=40 each in the 0.1 mg/kg midazolam, 0.05 mg/kg midazolam, and control with saline groups). Midazolam or saline was injected intravenously approximately 30 minutes before the end of the dental treatment. We used the Richmond Agitation and Sedation Scale (RASS) to assess the level of sedation and drowsiness at emergence phase in the operating room. We also used the Pediatric Anesthesia Emergence Delirium Scale (PAED) to assess the level of agitation and delirium at the full recovery phase from anesthesia in the recovery area. Results: At the emergence phase, the incidence of emergence agitation in the 0.1 mg/kg midazolam group was significantly lower than in the other groups (p=0.0010). At the recovery phase, there was no significant difference among the three groups. The odds ratio between PAED score and RASS score was 4.0 using logistic regression analysis. The odds ratio between PAED score and Disability was 2.5. Conclusion: Administration of a single dose of 0.1 mg/kg midazolam dose significantly decreases the incidence of severe emergence agitation at the emergence after sevoflurane anesthesia, but not at the recovery phase. Furthermore, the evaluation of sedative and agitation condition using RASS score at emergence from anesthesia is useful to predict occurrence of agitation in the recovery phase.

Effects of general anesthesia on postoperative sleep cycles in dentally disabled patients.

AIMS: Although it has been reported that general anesthesia affect the perioperative sleep cycle, no studies have yet evaluated how general anesthesia affects dentally disabled patients. In this study, we investigated the alteration of perioperative sleep cycles in dentally disabled patients receiving dental treatment under general anesthesia. SUBJECTS AND METHODS: The study included 16 patients receiving dental procedures under general anesthesia. Using a sleep monitoring mat, the patients' sleep cycles were measured at home from 5 days before the scheduled surgery date until 5 days after discharge following general anesthesia. The change in all the variables of sleep cycles were analyzed in comparison to the value in preoperative period. Daily differences in these variables were assessed for statistical analysis. RESULTS: The percentage of deep sleep (Stages 3 and 4) decreased significantly on postoperative day 1, and the percentage of light sleep increased. Furthermore, sleep cycles were significantly extended on postoperative day 1. CONCLUSION: The percentage of deep sleep decreased significantly on postoperative day 1 while the percentage of light sleep increased. Sleep cycles were also significantly extended on postoperative day 1. These results reveal that the sleep cycle is somehow affected on the first day following general anesthesia.

Nitrous Oxide Inhalation Sedation Through a Nasal High-Flow System: The Possibility of a New Technique in Dental Sedation.

High-flow nasal cannula (HFNC) systems are increasingly used for patients with both acute and chronic respiratory failure because of the clinical effectiveness and patient comfort associated with their use. Recently, HFNC has been used not only as a respiratory support device, but also as a drug delivery system. HFNC is designed to administer heated and humidified inspiratory oxygen flows (100% relative humidity at 37°C). Therefore, HFNC can provide high flows (up to 60 L/min) without discomfort. Moreover, HFNC improves oxygenation by exerting physiologic effects such as (a) dead-space washout and (b) moderate positive airway pressure. These characteristics and physiologic effects of HFNC may permit administration of high-flow nitrous oxide sedation while ensuring patient comfort and adequate sedative effect.