A Case of Successful Tracheal Tube Exchange With McGrath MAC for Tube Damage During Oral Surgery.

A patient undergoing a bilateral sagittal split and LeFort 1 maxillary osteotomy performed under general anesthesia required emergent intraoperative exchange of a potentially damaged nasotracheal tube. This exchange was smoothly performed under constant indirect visualization using the McGrath MAC video laryngoscopy system. After the exchange, ventilation of the patient dramatically improved. The removed endotracheal tube was torn 19 cm from the distal tip. The McGrath MAC was useful for visualizing the glottis and confirming the entire course of the tube exchange despite the patient's having a difficult airway (Cormack-Lehane grade 3).

[The advantage and harmful effects of nitrous oxide in dental management].

Frequency of using nitrous oxide (N2O) in anesthetic field decreased recently by the influence of the environmental problems and the widespread use of intravenous agents. In dental treatment, however, inhalation sedation using low concentration of N2O has been effectively used to relax dental patients. Nitrous oxide inhalation sedation for dental treatment generally involves the use of a combination of low-dose N2O and high-dose oxygen. Low-dose N2O induces the relaxation of psychological tension in dental patients who have "dental phobia". Also, high-dose oxygen would contribute to manage "(pre) syncope" due to pain stimuli. Thus, N2O inhalation sedation is effective for the dental treatment, although the leak of N2O affects the health of dental staffs. The present review described the advantage and harmful effects of N2O in dental management.

Influence of blood pressure on cardio-ankle vascular index (CAVI) examined based on percentage change during general anesthesia.

Cardio-ankle vascular index (CAVI) and brachial-ankle pulse wave velocity (baPWV) are non-invasive methods for estimating arterial distensibility. The purpose of this study is to evaluate whether CAVI as an index of true arterial stiffness is superior to baPWV based on the percentage change in hemodynamics under general anesthesia. CAVI (segment from heart to ankle), k-CAVI (heart to knee) and baPWV (brachial to ankle) in 30 oral surgery patients were measured to compare the decreased blood pressure (BP) after 10 min of tracheal intubation during general anesthesia with the control BP (after 5 min of rest). General anesthesia was performed under endotracheal intubation through intravenous injection of propofol, fentanyl and vecuronium or rocuronium. In both the elderly (65 years) and middle-aged (<65 years) groups, CAVI and k-CAVI did not change during general anesthesia, whereas baPWV and systolic BP (SBP) showed a statistically significant decrease. Thus, the changes in CAVI (ΔCAVI) and k-CAVI (Δk-CAVI) showed no significant correlations with those of SBP (ΔSBP), whereas the changes in baPWV (ΔbaPWV) were significantly correlated with ΔSBP. ΔCAVI and Δk-CAVI showed no significant differences between the two groups, whereas ΔbaPWV and ΔSBP in the elderly group was much higher than that in the middle-aged group. Measurement of CAVI was not affected by the decrease in BP during general anesthesia. In contrast, baPWV was significantly influenced by changes in BP. These findings suggest that CAVI is a useful index of true arterial stiffness and is superior to baPWV.

Measurement of cerebral reactive hyperemia at the initial post-ischemia reperfusion stage under normothermia and moderate hypothermia in rats.

Inhibition of the initial events occurring immediately after ischemia-reperfusion seems to be beneficial for reducing the extent of subsequent chronic neuronal cell injury. We investigated the effects of moderate hypothermia (32 degrees C) commencing 30 min before ischemia on reactive hyperemia by measuring cerebral blood flow (CBF) with a laser-Doppler flowmeter at the initial ischemia-reperfusion stage (60 min) following 10 min of global cerebral ischemia in rats. In normothermia, CBF was increased to approximately 240% and decreased thereafter, although it remained at approximately 150% after 60 min of ischemia-reperfusion. In contrast, hypothermia increased CBF to more than 270% after ischemia-reperfusion, then recovered to the basal level within 30 min. The period of reactive hyperemia under normothermia tended to be shortened by pre-administration of an NMDA antagonist, in a manner similar to hypothermia. Furthermore, hypothermia inhibited the presence of cells with caspase-3-like immunoreactivity in the hippocampal CA1 sector after 8 h of ischemia-reperfusion. Our findings indicate that hypothermia tends to shorten the period of reactive hyperemia during the initial ischemia-reperfusion stage. This phenomenon may be partly associated with activation of NMDA receptors and a beneficial effect of hypothermia in resisting progression of the neurotoxic cascade in the first 8 h after ischemia-reperfusion.

Postoperative mental disorder following prolonged oral surgery.

A prolonged period of oral surgery is a potential risk factor of postoperative mental disorders although no such report has been published to date. We retrospectively studied perioperative features in 36 patients who underwent prolonged (10 hours or more) of oral surgery. Patients were categorized as pre-delirium (Pre-D) when they manifested 1 or 2 symptoms and delirium (D) when they showed more than 2 symptoms, according to the modified International Classification of Diseases, 10th edition. Of the 36 patients who returned to a normal mental state without drug therapy, 13 were classified as D and 14 were Pre-D. A number of patients had moderate complications preoperatively, and massive hemorrhaging occurred during the operation in some Pre-D and D patients. Age was greater in D (62.0 +/- 9.9 years) than in Pre-D (56.0 +/- 13.8 years) patients. Propofol-based general anesthesia was most commonly employed. The time prior to appearance of pre-delirium was significantly shorter in D (30.0 +/- 16.7 hours) than in Pre-D (55.0 +/- 35.0 hours) group patients. Our results indicate that, in general, patients predisposed to postoperative mental disorders have moderate complications preoperatively, are generally older than 50-years-old, receive propofol-based general anesthesia and/or experience a massive hemorrhage during the operation.

[Intravenous anesthesia using continuous administration of propofol and fentanyl: fentanyl administration procedure and quality of awareness].

BACKGROUND: We studied total intravenous anesthesia using continuous administration of propofol and fentanyl and examined especially the method of fetanyl administration. METHODS: Anesthesia was induced with fentanyl 2 micrograms.kg-1 and propofol 2 mg.kg-1. Fentanyl 1 microgram.kg-1 was then administered before the start of the operation and infused continuously at a rate of 0.02 microgram.kg-1.min-1 during operation. Propofol was also infused continuously at 4-10 mg.kg-1.min-1. RESULTS: These methods allowed a significant reduction in the necessary dose of fentanyl and propofol compared with ordinary methods, and a stable general condition was maintained during the operation. Additionally, high quality of awareness was obtained after the recovery. CONCLUSIONS: This continuous administration procedure of fentanyl reduced the total doses of both propofol and fentanyl, allowing high quality of awareness after the recovery.