Total Intravenous Anesthesia in a Malignant Hyperthermia-Susceptible Patient with Klinefelter Syndrome Undergoing Orthognathic Surgery.

ABSTRACT: A patient with Klinefelter syndrome and skeletal Class III malocclusion experienced a malignant hyperthermia-like reaction while undergoing orthognathic surgery. The patient fully recovered after prompt diagnosis and management, and surgery was reattempted under total intravenous anesthesia. The patient was discharged without any anesthetic complications and was satisfied with the surgical results. This is the first described case of a malignant hyperthermia-like event in a patient with Klinefelter syndrome. Total intravenous anesthesia may be safely administered in malignant hyperthermia-susceptible patients who require orthognathic surgery.

Cough reflex under intravenous sedation during dental implant surgery is more frequent during procedures in the maxillary anterior region.

PURPOSE: The present study was performed to evaluate the incidence of cough episodes and the association between cough episodes and patient-related and site-specific parameters during implant surgery when performed under intravenous sedation. MATERIALS AND METHODS: One hundred forty-seven patients scheduled for dental implant surgeries under intravenous sedation were enrolled in this study. Heart rate, blood pressure, percutaneous oxygen saturation, and bispectral index were monitored. Sedation was induced intravenously by a bolus administration of midazolam and maintained by a continuous administration of propofol. Sedation level was adjusted to achieve scores of 3 to 4 on the Ramsay Sedation Scale. Surgical procedures were divided into 11 stages. Implant sites were labeled as right maxillary molar, maxillary anterior, left maxillary molar, right mandibular molar, mandibular anterior, and left mandibular molar sites. When coughing occurred, heart rate, blood pressure, percutaneous oxygen saturation, bispectral index, procedure being performed, and surgical site being stimulated were recorded. RESULTS: One hundred seventy-two cough episodes were observed in 97 patients (66%). Cough episodes occurred during all stages of surgery but were substantially more frequent during preparation of the implant site. The incidence of cough episodes was significantly higher at the maxillary anterior site and lowest at the right mandibular molar areas. CONCLUSION: These findings suggest that difficulties in swallowing and in the suction of intraoral fluids have variable effects at different surgical sites. Careful suction of intraoral water and an appropriate sedation level are required, especially in procedures in the maxillary anterior region.

Risk factors with intravenous sedation for patients with disabilities.

The purpose of this study was to identify the risk factors associated with low peripheral oxygen saturation (SpO2) and delayed recovery of dental patients with disabilities after intravenous sedation. A total of 1213 patients with disabilities were retrospectively investigated with respect to demographic parameters and sedation conditions. Multivariate logistic analyses were conducted for patients with an SpO2 <90% and a recovery period of >60 minutes to identify the risk factors for poor sedation conditions. A significant odds ratio related to decreased SpO2 was observed for age, sex, midazolam and propofol levels, concurrent use of nitrous oxide, cerebral palsy, Down syndrome, and mental retardation. The most problematic patients were those diagnosed with Down syndrome (odds ratio, 3.003-7.978; 95% confidence interval; P < .001). Decision tree analysis showed an increased risk of decreased SpO2 in males with Down syndrome or after administration of >0.493 mg/kg propofol in combination with midazolam. An increased risk of delayed awakening was seen in patients aged less than 21 years and in males administered >0.032 mg/kg of midazolam. Intravenous sedation for dental patients with disabilities, particularly those with cerebral palsy, Down syndrome, or mental retardation, increases the risk of decreased SpO2. In addition, delayed recovery is expected after midazolam administration.

A comparison of fospropofol to midazolam for moderate sedation during outpatient dental procedures.

Moderate intravenous (IV) sedation combined with local anesthesia is common for outpatient oral surgery procedures. An ideal sedative agent must be safe and well tolerated by patients and practitioners. This study evaluated fospropofol, a relatively new sedative/hypnotic, in comparison to midazolam, a commonly used benzodiazepine, for IV moderate sedation during oral and maxillofacial surgery. Sixty patients were randomly assigned to either the fospropofol or the midazolam group. Each participant received 1 µg/kg of fentanyl prior to administration of the selected sedative. Those in the fospropofol group received an initial dose of 6.5 mg/kg, with 1.6 mg/kg supplemental doses as needed. Those in the midazolam group received initial doses of 0.05 mg/kg, followed by 0.02 mg/kg supplemental doses. The quality of sedation in each patient was evaluated with regard to (a) onset of sedation, maintenance, and recovery profile; (b) patient and surgeon satisfaction; and (c) hemodynamic stability and adverse effects. The fospropofol group demonstrated shorter physical recovery times than midazolam patients, taking a mean of 11.6 minutes versus 18.4 minutes for physical recovery (P = .007). Cognitive recovery comparison did not find any difference with a mean of 7.5 minutes versus 8.8 minutes between the 2 drug groups (P = .123). The fospropofol group had a higher rate of local anesthetic injection recall (90.5 vs 44.4%, P = .004). Other parameters of recall were comparable. Two adverse effects demonstrated significance, with more patients in the midazolam group experiencing tachycardia (48.2 vs 9.4%, P = .001), and more patients in the fospropofol group experiencing perineal discomfort (40.6 vs 0, P < .001). No significant difference was found in any other measures of sedation safety, maintenance, or satisfaction. Fospropofol, when administered intravenously by a dentist anesthesiologist at the indicated dose in this study, appears to be a safe, well-tolerated alternative to midazolam for intravenous moderate sedation during minor oral surgery procedures.

Midazolam is associated with delay in recovery and agitation after ambulatory general anesthesia for dental treatment in patients with disabilities: a retrospective cohort study.

PURPOSE: Some patients with intellectual disabilities (IDs) who undergo total intravenous anesthesia (TIVA) have complications associated with the anesthesia such as prolonged recovery. The purposes of this study were to estimate the frequency of TIVA complications among patients with IDs and to identify factors associated with TIVA complications. MATERIALS AND METHODS: This study was designed as a retrospective cohort study. Study samples were selected from the clinical records of patients with IDs who underwent ambulatory general anesthesia in a special dental clinic at the Okayama University Hospital, Okayama, Japan. Predictor variables were patient background, anesthesia-related variables, and dental treatment. Outcome variables were delayed recovery and the complication of agitation. Factors affecting delayed recovery and complications were examined with multivariable analysis. RESULTS: We enrolled 106 cases (81 male and 25 female patients) in this study. The mean age was 23.9 years. Serious complications were not observed in any cases. The amount of intravenous midazolam was an independent determinant of delayed recovery. Oral midazolam contributed to delayed recovery, although it is very useful for induction in patients with a high level of fear. Oral midazolam and a younger age were independent predictors of agitation. CONCLUSIONS: Intravenous midazolam may not have an advantage in ambulatory general anesthesia. Oral midazolam contributes to delayed recovery and is an independent predictor of agitation.

Cross-sectional Study of PONV Risk Factors for Oral Surgery After Intubated General Anesthesia With Total Intravenous Anesthesia.

OBJECTIVE: The incidence of postoperative nausea and vomiting (PONV) after general anesthesia with total intravenous anesthesia (TIVA) was reported to be significantly lower than with volatile inhalational agents (13.3% vs 25%). However, no investigation of PONV risk factors associated with TIVA has ever been reported. This cross-sectional retrospective study aimed to investigate whether known risk factors influenced PONV in intubated general anesthetics utilizing TIVA for dental or oral and maxillofacial surgery. METHODS: Subjects were 761 patients who underwent dental or oral and maxillofacial surgery under TIVA with propofol, fentanyl, and remifentanil. Univariate and multivariable logistic regression analyses were performed using PONV (within 24 hours) as the dependent variable and previously reported risk factors as independent variables. RESULTS: Age (odds ratio [OR]: 1.020 per year decrease; 95% confidence interval [CI]: 1.0002-1.0418; P = .047) and female sex (OR: 2.73; 95% CI: 1.60-4.84; P < .001) were positively associated with PONV. Sagittal split ramus osteotomy (SSRO) (OR: 2.28; 95% CI: 1.21-4.33; P = .011) and bimaxillary osteotomy (OR: 5.69; 95% CI: 2.09-15.99; P < .001) were more likely to be associated with PONV than operations that were neither bimaxillary osteotomy nor SSRO. Late PONV (2-24 hours) had an ∼2.7 times higher incidence than early PONV (0-2 hours). CONCLUSION: These findings suggest further PONV countermeasures, aside from TIVA with propofol and prophylactic antiemetics for orthognathic surgeries especially bimaxillary osteotomy, are needed.

[The improvement of safe sedation and dental treatment in patients with metabolic syndrome].

The paper concerns the anesthetic aspects of safe conscious sedation and dental treatment of patients with metabolic syndrome. BIS monitoring in combination with routine pulse oximetry and blood pressure measurement is getting dental sedation safer. Independently of the bolus or continuous intravenous midazolam infusion the investigators approved high efficacy of bispectral index in benzodiazepine dose titration. Successful dental treatment under conscious sedation and no evident associated with analgesia complications show the importance of BIS-monitoring in the improvement of safe sedation and dental treatment in patients with metabolic syndrome.

Complications associated with anesthesia administered for dental treatment.

This assessment sought to identify and quantify complications that occur with anesthesia administration during dental treatment of consecutive patients who received care through the University of Pittsburgh School of Dental Medicine's (UPSDM) Department of Anesthesiology. This prospective study was completed by participating anesthesia caregivers at the UPSDM as a case-by-case evaluation. A standardized form delineating possible complications was used to collect data following 286 consecutive outpatient anesthetic cases administered within the UPSDM. After statistical analysis of five types of administered anesthesia, the overall complication rate was 22.4% in 286 cases. All of the complications were considered to be mild (90.6%) or moderate (9.4%); there were no reports of severe complications. The complications encountered most frequently were airway obstruction (18 reports) and occurrence of nausea/vomiting (12 reports). ASA classification, anesthetic technique, pre-existing medical findings, and the type of dental procedure performed all were variables that were found to affect the incidence of anesthesia-related complications. The overall complication rate from anesthesia administered during dental care is similar to or less than that reported within the hospital operating system environment.

Comparison of methohexital and propofol use in ambulatory procedures in oral and maxillofacial surgery.

PURPOSE: Short-acting anesthetic agents, such as propofol and methohexital, are commonly used for ambulatory procedures in the practices of oral and maxillofacial surgeons (OMS). This study compares the safety and anesthetic outcomes of propofol and methohexital. In addition, the study compares the safety and outcomes of these agents when administered either by an OMS who simultaneously provides anesthesia and performs the procedure (anesthetist/surgeon), or by a non-OMS provider of anesthesia (anesthesiologist or certified registered nurse anesthetist; CRNA) whose sole obligation is to provide anesthesia. MATERIALS AND METHODS: This is a prospective study of anesthesia techniques used in an office-based ambulatory setting by OMS throughout the United States, in which either propofol or methohexital was used for sedation/anesthesia. The study variables included demographic information, anesthetic agent, adverse outcomes related to anesthesia, operative procedure, and provider of anesthesia. These variables were compared with the patient group that received a benzodiazepine/narcotics regimen for sedation (control group). Bivariate (contingency tables) and multivariate (logistic regression) analyses were conducted. P < or = .05 was considered statistically significant. RESULTS: The study included 47,710 patients who met the inclusion criteria: 26,147 (54.8%) patients were in the propofol group, 15,859 (33.2%) were in the methohexital group, and 5,704 (12.0%) were in the benzodiazepine group. Among all study patients, 333 (0.7%) had an adverse event. The most common complication was nausea and vomiting without aspiration. Of the patients in the propofol group, methohexital group, or benzodiazepine group, 0.4%, 1.1%, and 0.8% had an adverse event, respectively. The higher number of complications among patients in the methohexital group compared with patients in the other 2 groups was statistically significant. Of 26,147 patients in the propofol group, 23,799 (91.0%) received anesthesia from an anesthetist/surgeon (OMS), and 2,368 (9.1%) from an anesthesiologist or nurse anesthetist (non-OMS). A total of 109 patients (0.4%) had an adverse event. The majority of patients who received anesthesia from a non-OMS were in the propofol group (2,368 of 2,404 patients; 98.5%). There was no statistically significant difference in the occurrence of adverse outcomes when comparing patients in the propofol group who received anesthesia from an OMS with those who received anesthesia from a non-OMS (P = .24, bivariate analysis; P = .33, multivariate analysis). CONCLUSIONS: There is a statistically significant increase in adverse events related to methohexital compared with propofol or benzodiazepine/narcotics for anesthesia. Propofol appears to have the lowest risk for adverse events. There is no statistically significant difference in the number of adverse outcomes between the administration of propofol for ambulatory surgery by OMS as an anesthetist/surgeon and anesthesiologist/nurse anesthetist. It remains critical that our specialty maintains the highest standards, to provide safe anesthesia and to reduce adverse anesthetic events.

Randomized trial of a novel double lumen nasopharyngeal catheter versus traditional nasal cannula during total intravenous anesthesia for gastrointestinal procedures.

STUDY OBJECTIVE: Patients undergoing general anesthesia routinely experience episodes of hypoxemia. There are multiple causes of procedural oxygen desaturation including upper airway obstruction and central hypoventilation. We hypothesize that oxygen supplementation via nasopharyngeal catheter (NPC) will decrease the number of episodes of hypoxemia as compared to traditional NC oxygen supplementation in patients undergoing general anesthesia provided by an anesthesia provider for gastrointestinal endoscopy procedures. DESIGN: Randomized control trial. SETTING: Endoscopy suite. PATIENTS: Sixty patients undergoing intravenous general anesthesia for endoscopic gastrointestinal procedures that did not require endotracheal intubation were enrolled. INTERVENTIONS: Patients were randomized to receive supplemental oxygen by either a standard nasal cannula or a nasopharyngeal catheter. Initial oxygen flow rate was 4l/min and titrated at the anesthesia provider's discretion. Intravenous anesthetic consisted of a propofol infusion. MEASUREMENTS: Hypoxemia was defined as a pulse oximetry reading of <92%. Secondary outcomes included number of airway assist maneuvers such as jaw lift or other airway interventions. MAIN RESULTS: Of the 60 enrolled patients; three subjects in the NPC group were excluded from further analysis. There was no difference between group in age, ASA classification, Body Mass Index, oropharyngeal classification or total propofol dose. Patients who received nasopharyngeal oxygen supplementation were less likely to experience a clinically significant oxygen desaturation event 3 of 27 (11.0%) versus 12 of 30 subjects (40.0%), p=0.013. Interventions to assists with airway management were required for fewer patients in the NPC group 4 (14.8%) versus the NC group, 17 (56.7%), p=0.001. CONCLUSION: Oxygen supplementation via a nasopharyngeal catheter during intravenous general anesthesia resulted in significantly fewer episodes of hypoxemia and number of airway assist maneuvers. Future studies are needed to assess the utility of NPC in other clinical environments where supplemental oxygen is required in the setting of potential airway obstruction.

The implications of substance misuse for intravenous conscious sedation practice.

Substance misuse is a major health concern in the United Kingdom, as the consequences for individuals are significant and may include multisystem organ damage. It is important for the dentist to know which patients are misusing substances as some pharmacological agents routinely used in dental practice may be contraindicated. The dentist should be aware of the range of clinical presentations that may arise from substance misuse and when suspected, a thorough drug history must be obtained. Patients may require special consideration and further investigations when planning elective procedures, particularly under intravenous conscious sedation. Therefore, management within a specialist centre and liaison with other health professionals may be indicated to ensure treatment is provided safely.

Lethal septic shock after dental scaling in a healthy dog due to Ochrobactrum anthropi-contaminated propofol.

A 10-year-old, 6-kg male Yorkshire terrier dog was scheduled for routine dental cleaning. No significant problem was observed either during anaesthesia, which was induced with propofol, or during recovery. However, 2 hours after discharge, the dog's owner returned to the clinic, complaining that the animal was lethargic and had had bloody diarrhoea. On physical examination the dog was depressed, dyspnoeic, tachycardic and hypoglycaemic. Despite supportive treatment, the dog deteriorated and died within a few hours.A presumed diagnosis of sepsis was confirmed by laboratory testing. Bacteriological and molecular examinations of both premortem blood samples and the anaesthetic, highlighted the presence of Ochrobactrum anthropi, an opportunistic pathogen usually associated with immunocompromised hosts with indwelling medical devices. To the authors' knowledge, this is the first case of sepsis in a healthy dog due to contamination of an anaesthetic solution by O. anthropi, suggesting a potential role of this microorganism as an emerging pathogen.

Incidence and extent of venous sequelae with intravenous diazepam utilizing a standardized conscious sedation technique. Part II: Effects of injection site.

The effects of site of venipuncture on the incidence of venous sequelae, utilizing a standard protocol, were assessed on 48 human subjects. Data were also recorded based on various demographic and clinical variables, including age, sex, race, vein diameter, dose, procedure time, IV fluid volume, injection pain and initial blood flow velocity. When the site of venipuncture was the antecubital fossa there was a significantly lower incidence of venous sequelae than when the venipuncture site was the dorsum of the hand, with the significant variables being venous diameter and procedure time. These findings further support the antecubital fossa as a preferred venipuncture site to the dorsum of the hand; however, there was a sufficient incidence of venous complications (37%) when the antecubital fossa was used to warrant consideration of contributory factors other than site. It appears that time of continuous infusion is a critical element and should be kept at a minimum. Also, subjects in whom Valium was injected demonstrated significantly more venous sequelae than those in whom 5% dextrose in water was injected, confirming previous reports that diazepam is irritating to the endothelial lining and thus is thrombogenic.

Intravenous sedation of the periodontal surgical patient.

A safe sedation technique for the periodontal surgical patient has been discussed. By utilizing the drugs discussed and titrating the dosage to the needs of the patient, intravenous sedation will last long enough to complete the selected periodontal surgical procedure. The Jorgenson combinatione of drugs seems ideal for procedures lasting two or more hours, while diazepam is more desirable for those of shorter duration. Patient and surgeon comfort is coexistent with the patient's safety. Although the intravenous route is considered to be the most dangerous of all, when it is employed with optimum care and on well-selected patients, it is possibly one of the safest.

Serious professional misconduct arising out of dental anaesthesia and sedation.

This paper reviews three recent decisions of the Judicial Committee of the Privy Council on appeal from decisions of the Professional Conduct Committee of the General Dental Council, in which questions of general anaesthesia, sedation and resuscitation were raised. The recommendations of the Poswillo Report on general anaesthesia, sedation and resuscitation in dentistry of March 1990 are considered with respect to these three cases, and an assessment made as to whether or not the incidents which gave rise to them would have occurred had the recommendations been implemented. The implications of the Poswillo Report for the maintenance of professional standards of conduct by the General Dental Council in relation to the use of general anaesthesia, sedation and resuscitation are discussed.

Oxygen saturation during third molar removal with local anaesthetic alone and in combination with intravenous sedation.

Oxygen saturation was recorded in 96 adults undergoing removal of third molar teeth in the dental surgery. Half the patients received local anaesthetic alone; the remainder received, in addition, intravenous midazolam. Patients receiving sedation sustained the greatest falls in oxygen saturation. However, in 10 out of 48 patients undergoing third molar removal with LA alone, oxygen saturations in the range of 93-89% were recorded. The results of this study suggest that all patients undergoing removal of third molars are at risk of hypoxia. Short episodes of hypoxia may be of little consequence in healthy patients, but in compromised patients early detection may avoid serious complications.

Intravenous sedation: the risk to the dentist.

The risk of intravenous sedation to the patient is well documented. It now appears that there is also a risk to the dentist, not so much one of health but one of illegality, loss of career and personal esteem. Martyn Fields looks at some of the evidence, and gives advice on how to avoid a dangerous predicament.

Prevention of venous complications from intravenous anesthesia.

Vascular complications following the use of intravenous sedative drugs continue to be a problem in dental anesthesia. Etiological factors associated with pain and thrombophlebitis are reviewed. From reports in the literature and clinical experience, venous complications from intravenous sedation may be reduced by utilizing large veins with the dilution of sedative agents in a fast running intravenous infusion. Intravenous lidocaine may be of use to block reflex venospasm and pain.

Prospective study of venous complications following intravenous diazepam in dental outpatients.

The incidence of venous complications following intravenous diazepam administered to 190 dental out-patients was investigated in a prospective, randomized study. The administration into the smaller veins of the hand and forearm resulted in a significant increase in the incidence of thrombophlebitis. Use of a plastic catheter in place of an infusion needle or flushing with 150 ml of saline did not alter the incidence of venous complications. These results suggest that use of the larger veins of the antecubital fossa can lower the incidence of venous complications encountered in clinical practice following the intravenous administration of diazepam. These findings also suggest that use of a plastic catheter or post-drug administration flushing with saline does not affect the incidence of venous complications.