Sole Sedative Agent Research Articles

Remimazolam As a Sole Sedative Agent for Gastrostomy Tubes Placed in the Interventional Radiology Suite: A Case Series.

Remimazolam is an ultrashort acting intravenous sedative-hypnotic approved for procedural sedation. We report a series of 8 cases of radiographically placed gastrostomy tubes using remimazolam as the sole anesthetic agent. Interventional radiology (IR) gastrostomy tube placement entails anesthetizing often complex patients in a nonoperating room environment. All 8 patients reported here underwent successful gastrostomy tube placement without the need for conversion to general anesthesia. Remimazolam is a feasible option to sedate patients for gastrostomy tube placement in the IR suite.

Subcutaneous alfaxalone for sedation of the domestic ferret (Mustela putorius furo)

BackgroundVeterinary care of the domestic ferret often utilizes chemical restraint for venipuncture, radiographs, and ultrasonography. Common forms of chemical restraint for ferrets include inhalant anesthetics and parenteral sedatives. Disadvantages of these forms of chemical restraint include adverse patient reaction and environmental contamination for inhalant anesthetics while small muscle mass and patient reactivity are challenging for intramuscular injections. Alfaxalone is a unique neurosteroid anesthetic that can be used as an induction agent intravenously and a sedative agent intramuscularly and subcutaneously. Subcutaneous injection appears to be well tolerated in small exotic species due to the increased volume the subcutaneous space can accommodate as well as the ease of administration. MethodsA randomized, blinded, complete crossover study evaluating two doses (10 mg/kg and 12.5 mg/kg) of subcutaneous (SC) alfaxalone alone was performed in 10 clinically healthy ferrets (5 neutered males and 5 spayed females). Once alfaxalone was administered sedation scores (body posture, righting reflex, jaw tone, front limb withdrawal, and toe pinch) and vital parameters (heart rate, respiratory rate, rectal temperature, SpO2 and blood pressure) were evaluated at regular intervals. ResultsSedation characterized by the loss of righting reflex for more than ten minutes was observed in 90% of ferrets in both groups. The higher dose of alfaxalone (12.5 mg/kg) produced a statistically significant increase in the duration of sedation, as well as in the values of all sedation scores. Temperature significantly decreased over time for both groups, while SpO2 and respiratory rate did not display any significant changes. At both doses, no cardiovascular depression was noted but there were significant increases in heart rate and blood pressure parameters. ConclusionSubcutaneous alfaxalone in ferrets produces adequate sedation characterized by the loss of righting reflex and easy limb manipulation with no significant adverse effects. This type of sedation is appropriate for noninvasive procedures such as a physical exam, ultrasonography, and radiographic positioning without manual restraint. The limitations for SC alfaxalone, as a sole sedative agent, include the variable range in times to onset and variable durations of sedation.

Outcomes of dexmedetomidine sedation for drug-induced sleep ciné magnetic resonance imaging studies in pediatric obstructive sleep apnea patients.

Dexmedetomidine is utilized as a sedative agent for drug-induced sleep cine magnetic resonance imaging studies due to its ability to mimic natural sleep and lack of respiratory depressant effects. The outcomes of dexmedetomidine sedation such as respiratory complications and unplanned admissions in obstructive sleep apnea patients undergoing these studies are currently unknown. To describe the outcomes of dexmedetomidine sedation for outpatient drug-induced sleep magnetic resonance imaging in pediatric patients with obstructive sleep apnea. This is a retrospective chart review conducted in pediatric patients with obstructive sleep apnea undergoing outpatient drug-induced sleep ciné magnetic resonance imaging studies with dexmedetomidine sedation. Demographics, comorbidities, polysomnography study results, vital signs, respiratory complications, airway interventions, successful completion of the scan, and unplanned hospital admissions were measured. We analyzed 337 patients aged 2-18years (median age of 11years). The imaging was completed with dexmedetomidine as the sole sedative agent in 61% (N=207) patients. Ketamine was administered as additional sedative agent in 36% (N=122) of the patients. There was no difference in sedation-related adverse events and respiratory complications with regard to the severity of sleep apnea with the exception of mild desaturation episodes (SpO2 85%-90%). Patients who received additional sedative agents had significantly longer recovery room stay (71.5 [44] vs 55 [39] minutes; 95% CI of difference [9 to 23min], p<0.001) and total periprocedural stay (164.5 [52] vs 138 [64] minutes; 95% CI of difference [17 to 35min], p<.001). Dexmedetomidine alone or along with ketamine provided acceptable sedation in majority of the patients with obstructive sleep apnea undergoing outpatient diagnostic sleep magnetic resonance imaging studies without significant respiratory adverse events regardless of the severity of sleep apnea. Sedation failure and unplanned admissions are rare, and routine planned admission may not be required for this patient population.

Evaluation of Dexmedetomidine Dosing in Obese Critically Ill Patients

Background: Dexmedetomidine is a highly selective α2-adrenoreceptor agonist that produces dose-dependent sedation, anxiolysis, and analgesia without respiratory depression. Due to these ideal sedative properties, there has been increased interest in utilizing dexmedetomidine as a first-line sedative for critically ill patients requiring light sedation. Objective: To evaluate the ability to achieve goal intensive care unit (ICU) sedation before and after an institutional change of dosing from actual (ABW) to adjusted (AdjBW) body weight in obese patients on dexmedetomidine. Methods: This study included patients ≥ 18 years old, admitted to a surgical or medical ICU, required dexmedetomidine for at least 8 hours as a single continuous infusion sedative, and weighed ≥ 120% of ideal body weight. Percentage of RASS measurements within goal range (−1 to +1) during the first 48 hours after initiation of dexmedetomidine as the sole sedative agent or until discontinuation dosed on ABW compared to AdjBW was evaluated. Results: 100 patients were included in the ABW cohort and 100 in the AdjBW cohort. The median dosing weight was significantly higher in the ABW group (95.9 [78.9-119.5] vs 82.2 [72.1-89.8] kg; p = 0.001). There was no statistical difference in percent of RASS measurements in goal range (61.5% vs 69.6%, p = 0.267) in patients that received dexmedetomidine dosed based on ABW versus AdjBW. Conclusion: Dosing dexmedetomidine using AdjBW in obese critically ill patients for ongoing ICU sedation resulted in no statistical difference in the percent of RASS measurements within goal when compared to ABW dosing. Further studies are warranted.

Sedation Characteristics of Intranasal Alfaxalone in Adult Yucatan Swine.

Compared with intravenous and intramuscular methods, intranasal administration of sedatives is a less invasive and nonpainful technique. In this prospective, randomized, crossover study, we evaluated the sedative characteristics of 2 doses (1 and 2 mg/kg) of alfaxalone administered intranasally to 7 adult Yucatan swine. We compared sedation scores before and after administration of alfaxalone and between groups by using a composite sedation scoring system (range, 0 to 12, with 12 being the highest level of sedation)). Pigs were randomly assigned to receive 2 doses of intranasal alfaxalone (1 mg/kg [A1]); 2 mg/kg [A2]) as 2 separate events in a crossover design with a 60-d washout period. Categories scored were posture, palpebral droop, uninhibited behavior, drowsiness, and acceptance of anesthetic facemask. Sedation scores were collected before sedation was administered and then every 3 min for 30 min afterward. Instilled volumes (mean ± 1 SD) were 5.7 ± 0.5 and 11.3 ± 0.8 mL for A1 and A2, respectively. Both alfaxalone doses produced significant increases in sedation scores compared with baseline. Median sedation scores for A1 (6; range, 4-12) were not different from those for A2 (6; range, 6 to 12). Intranasal administration of alfaxalone as the sole sedative agent increased sedation scores from baseline, achieving peak sedation at 6 to 9 min after instillation of A2. However, sedation scores were similar between the 2 groups, and neither dose produced sufficient sedation to facilitate handling or the performance of any clinical procedures. Given the concentration of alfaxalone solution currently available, volume is the major limiting factor regarding testing higher doses of this drug for its use as a sole sedative agent in swine.

Recovery time after oral and maxillofacial ambulatory surgery with dexmedetomidine: an observational study.

To evaluate the relationship between pharmacokinetic descriptors of dexmedetomidine (predicted area under the curve during the procedure, predicted plasma level at the end of the procedure, and duration of procedure) and sedation depth (proportion of time with bispectral index < 85 during the procedure) with recovery time after ambulatory procedures. Clinical observational study of patients undergoing oral and maxillofacial ambulatory surgery with dexmedetomidine as sole sedative agent. Patients received a loading dose of dexmedetomidine (0.25-1μgkg-1) followed by a maintenance infusion (0.2-1.4μgkg-1h-1) to keep a bispectral index < 85 until 5min before the end of the procedure, and were transferred to a post-anesthesia care unit until criteria for discharge were met. Data from 75 patients was analyzed. Sedation depth was directly associated with recovery time (Pearson correlation coefficient [r] = 0.26; p = 0.024). Around 7% of the variation in recovery time was explained by the proportion of time with bispectral index < 85. No association with procedure duration (r = 0.01; p = 0.9), predicted area under the curve (r = 0.1; p = 0.4), or predicted plasma level of dexmedetomidine at the end of the procedure (r = 0.12; p = 0.3) with recovery time was observed. Sedation depth with dexmedetomidine could play a role in increasing recovery time after oral and maxillofacial ambulatory surgery. In our study, the pharmacokinetic descriptors of dexmedetomidine did not seem to influence recovery time. Sedation depth with dexmedetomidine could play a role in increasing recovery time after ambulatory procedures.

Comparison between dexmedetomidine and propofol as sedatives for critically ill patients in intensive care units

Background: Regarding using of sedation in the intensive care unit (ICU) should allow the patient to be more comfortable, calm, cooperative, and at the same time easily arousable without delay niether weaning nor prolonged mechanical ventilation.Objective: The aim of my study is to compare the effect of dexmeditomidine Versus propofol for sedation and hemodynamic stability in a critically ill patient.Patient and method: A randomized study of 44 patients admitted to ICU; 22 of them received dexmedetomidine and the other 22 patients received propofol for sedation. The level of consciousness, blood pressure, heart rate, respiratory rate and requirement for adjuvants to reach the target level of sedation were monitored for the first 12 hours.Result: By applying Null hypothesis it was found that dexmedetomidine was significantly effective when compared with propofol for sedation with a p-value less than 0.001, while it was not significantly effective when compared with propofol plus adjuvant with p-value&gt; 0.05.Conclusion: Dexmedetomidine is effective as a sole sedative agent with haemodynamic stability without the need to add any adjuvant to it, while propofol cause hypotension and bradycardia if used alone to reach our target level of sedation, but can be used with adjuvant to reach our target of sedation and haemodynamic stability.Keywords: Dexmedetomidine, Propofol, Sedation, ICU.&#x0D;

Efficacy of Dexmedetomidine as a Sole Sedative Agent in Small Diagnostic and Therapeutic Procedures: A Systematic Review.

Dexmedetomidine is an upcoming agent with sedative, anxiolytic, and analgesic properties. This review summarizes empirical evidence for the efficacy of dexmedetomidine as a sole sedative agent, and its effectiveness for small diagnostic and therapeutic procedure, in comparison with other frequently used sedatives. All randomized controlled trials on the effect of dexmedetomidine were reviewed. Pain level, patient satisfaction, operator satisfaction, procedure duration, recovery time, and hemodynamic and respiratory characteristics were examined. A total of 1993 patients (1,621 adults; 372 children) from 35 studies were included. In the adult studies, dexmedetomidine yielded significantly lower pain levels compared to the other sedatives (in 31.25% of the included studies) and significantly more patient satisfaction (68.2%). In studies on children, more favorable results concerning respiratory safety and the level of adequate sedation were found compared to the control sedatives. Implications for future studies are discussed.

Midazolam for sedation before procedures.

Midazolam is used for sedation before diagnostic and therapeutic medical procedures. It is an imidazole benzodiazepine that has depressant effects on the central nervous system (CNS) with rapid onset of action and few adverse effects. The drug can be administered by several routes including oral, intravenous, intranasal and intramuscular. To determine the evidence on the effectiveness of midazolam for sedation when administered before a procedure (diagnostic or therapeutic). We searched the Cochrane Central Register of Controlled Trials (CENTRAL to January 2016), MEDLINE in Ovid (1966 to January 2016) and Ovid EMBASE (1980 to January 2016). We imposed no language restrictions. Randomized controlled trials in which midazolam, administered to participants of any age, by any route, at any dose or any time before any procedure (apart from dental procedures), was compared with placebo or other medications including sedatives and analgesics. Two authors extracted data and assessed risk of bias for each included study. We performed a separate analysis for each different drug comparison. We included 30 trials (2319 participants) of midazolam for gastrointestinal endoscopy (16 trials), bronchoscopy (3), diagnostic imaging (5), cardioversion (1), minor plastic surgery (1), lumbar puncture (1), suturing (2) and Kirschner wire removal (1). Comparisons were: intravenous diazepam (14), placebo (5) etomidate (1) fentanyl (1), flunitrazepam (1) and propofol (1); oral chloral hydrate (4), diazepam (2), diazepam and clonidine (1); ketamine (1) and placebo (3); and intranasal placebo (2). There was a high risk of bias due to inadequate reporting about randomization (75% of trials). Effect estimates were imprecise due to small sample sizes. None of the trials reported on allergic or anaphylactoid reactions. Intravenous midazolam versus diazepam (14 trials; 1069 participants)There was no difference in anxiety (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.39 to 1.62; 175 participants; 2 trials) or discomfort/pain (RR 0.60, 95% CI 0.24 to 1.49; 415 participants; 5 trials; I² = 67%). Midazolam produced greater anterograde amnesia (RR 0.45; 95% CI 0.30 to 0.66; 587 participants; 9 trials; low-quality evidence). Intravenous midazolam versus placebo (5 trials; 493 participants)One trial reported that fewer participants who received midazolam were anxious (3/47 versus 15/35; low-quality evidence). There was no difference in discomfort/pain identified in a further trial (3/85 in midazolam group; 4/82 in placebo group; P = 0.876; very low-quality evidence). Oral midazolam versus chloral hydrate (4 trials; 268 participants)Midazolam increased the risk of incomplete procedures (RR 4.01; 95% CI 1.92 to 8.40; moderate-quality evidence). Oral midazolam versus placebo (3 trials; 176 participants)Midazolam reduced pain (midazolam mean 2.56 (standard deviation (SD) 0.49); placebo mean 4.62 (SD 1.49); P < 0.005) and anxiety (midazolam mean 1.52 (SD 0.3); placebo mean 3.97 (SD 0.44); P < 0.0001) in one trial with 99 participants. Two other trials did not find a difference in numerical rating of anxiety (mean 1.7 (SD 2.4) for 20 participants randomized to midazolam; mean 2.6 (SD 2.9) for 22 participants randomized to placebo; P = 0.216; mean Spielberger's Trait Anxiety Inventory score 47.56 (SD 11.68) in the midazolam group; mean 52.78 (SD 9.61) in placebo group; P > 0.05). Intranasal midazolam versus placebo (2 trials; 149 participants)Midazolam induced sedation (midazolam mean 3.15 (SD 0.36); placebo mean 2.56 (SD 0.64); P < 0.001) and reduced the numerical rating of anxiety in one trial with 54 participants (midazolam mean 17.3 (SD 18.58); placebo mean 49.3 (SD 29.46); P < 0.001). There was no difference in meta-analysis of results from both trials for risk of incomplete procedures (RR 0.14, 95% CI 0.02 to 1.12; downgraded to low-quality evidence). We found no high-quality evidence to determine if midazolam, when administered as the sole sedative agent prior to a procedure, produces more or less effective sedation than placebo or other medications. There is low-quality evidence that intravenous midazolam reduced anxiety when compared with placebo. There is inconsistent evidence that oral midazolam decreased anxiety during procedures compared with placebo. Intranasal midazolam did not reduce the risk of incomplete procedures, although anxiolysis and sedation were observed. There is moderate-quality evidence suggesting that oral midazolam produces less effective sedation than chloral hydrate for completion of procedures for children undergoing non-invasive diagnostic procedures.

Role of Dexmedetomidine for Sedation in Neurocritical Care Patients: A Qualitative Systematic Review and Meta-analysis of Current Evidence.

This systematic review appraises the clinical evidence on efficacy and safety of dexmedetomidine (DEX), as a sole sedative or as sedative adjunct in adult neurocritical care (NCC) patients. A database search was conducted to identify randomized clinical trials and observational studies reporting the use of DEX alone or as adjunct for sedation in NCC setting. The primary outcome was the occurrence of hemodynamic changes, whereas the secondary outcomes were sedative and analgesic efficacy, quality and time to awakening, and development of adverse events. Eight trials including 3 randomized controlled trials and 5 observational studies, enrolling 650 patients, were selected. All the retrieved studies had a high risk of bias and a low to moderate quality. Dexmedetomidine provided a better sedation score and reduced analgesic requirements when compared to propofol or midazolam sedation. No statistically significant difference in the combined hemodynamic effect (hypotension or bradycardia) between DEX and controls (risk ratio, 1.50; 95% confidence interval, 0.65-3.48; P = 0.34; I = 56%) was identified. Adverse events were not consistently reported. Available clinical literature supporting the efficacy and safety of DEX use in adult NCC setting is of limited quantity and quality. However, from the current evidence on the use of DEX in NCC, as sole sedative agent or as an adjunct, seems to be both efficient and safe.

Is dexmedetomidine a favorable agent for cerebral hemodynamics?

Is dexmedetomidine a favorable agent for cerebral hemodynamics?

Is dexmedetomidine really superior to propofol?

1. Sriganesh K, Reddy M, Jena S, Mittal M, Umamaheswara Rao GS. A comparative study of dexmedetomidine and propofol as sole sedative agents for patients with aneurysmal subarachnoid hemorrhage undergoing diagnostic cerebral angiography. J Anesth. 2014. doi:10.1007/s00540-014-1952-1. To the Editor: We read the article by Sriganesh et al. published ahead of print in your journal [1]. Based on a study conducted in 60 patients, the authors concluded that “dexmedetomidine appears to be superior to propofol as a sole sedative agent for sedation during cerebral angiography in patients with subarachnoid hemorrhage.” We noticed that the sample size calculation by Sriganesh et al. is based on the onset time for sedation in pediatric patients undergoing magnetic resonance imaging. The validity of this extrapolation to cerebral angiography (CA) needs to be confirmed. We feel that the authors should have conducted a pilot study and then calculated the sample size. In an ongoing trial in our center, on a similar patient population with similar intervention drugs, we conducted a pilot study. We calculated the necessary sample size to be as large as 92 patients in each group in order to show significant differences in movement during CA. Sedation for diagnostic CA needs to be evaluated further in patients of different grades of subarachnoid hemorrhage, as the sensorium of the patients will significantly influence the choice of drug and its dosages.

Propofol versus dexmedetomidine as a sole sedative for diagnostic flexible bronchoscopy: a randomized double-blind study

Context Sedation is commonly used to improve patients' tolerance and comfort during flexible bronchoscopy (FB). Dexmedetomidine is a relatively novel sedative for use in FB. Aims The aim of this study was to compare dexmedetomidine and propofol as sole sedative agent in terms of hemodynamics, efficacy, safety and tolerance to the procedure among patients undergoing FB. Settings and design This study was carried out in a tertiary care teaching hospital, and was a double-blind randomized-controlled trial. Patients and methods Sixty patients were analyzed. Group 1 received propofol (1 mg/kg bolus, then 5 mg/kg/h infusion); group 2 received dexmedetomidine (1 mg/kg bolus, followed by 0.7 mg/kg/h infusion). Intraoperative (IOP) SpO 2 , heart rate, mean arterial pressure, and respiratory rate were recorded at nine time points. Primary outcome variables were hemodynamic variables, level of sedation, and recovery time (to reach an Aldrete score 10/10). Results The dexmedetomidine group showed significantly lower mean heart rate than the propofol group at IOP 0 , IOP 2 , and IOP 4 . The mean arterial pressure was significantly higher throughout the procedure in the dexmedetomidine group compared with the propofol group ( P 4 and IOP 6 ( P 2 was noted in the dexmedetomidine group (97.0 ± 1.1). Incidences of bucking and coughing were significantly higher in the dexmedetomidine group. Bronchoscopist visual analogue scale scores for coughing and satisfaction were significantly lower in the propofol group ( P P < 0.001). Conclusion Propofol showed superiority over dexmedetomidine in terms of safety, efficacy, adverse-effect profile, and tolerance to the procedure in patients undergoing diagnostic flexible bronchoscopy.

High dose dexmedetomidine: effective as a sole agent sedation for children undergoing MRI.

Objective. To determine the efficacy and safety of high dose dexmedetomidine as a sole sedative agent for MRI. We report our institution's experience. Design. A retrospective institutional review of dexmedetomidine usage for pediatric MRI over 5.5 years. Protocol included a dexmedetomidine bolus of 2 μg/kg intravenously over ten minutes followed by 1 μg/kg/hr infusion. 544 patients received high dose dexmedetomidine for MRI. A second bolus was used in 103 (18.9%) patients. 117 (21.5%) required additional medications. Efficacy, side effects, and use of additional medicines to complete the MRI were reviewed. Data was analyzed using Student's t-test, Fisher's exact test, and Analysis of Variance (ANOVA). Main Results. Dexmedetomidine infusion was associated with bradycardia (3.9%) and hypotension (18.4%). None of the patients required any intervention. Vital signs were not significantly different among the subgroup of patients receiving one or two boluses of dexmedetomidine or additional medications. Procedure time was significantly shorter in the group receiving only one dexmedetomidine bolus and increased with second bolus or additional medications (P < 0.0001). Discharge time was longer for children experiencing bradycardia (P = 0.0012). Conclusion. High dose Dexmedetomidine was effective in 78.5% of cases; 21.5% of patients required additional medications. Side effects occurred in approximately 25% of cases, resolving spontaneously.

Safety of Propofol as an Induction Agent for Urgent Endotracheal Intubation in the Medical Intensive Care Unit

Propofol is known to provide excellent intubation conditions without the use of neuromuscular blocking agents. However, propofol has adverse effects that may limit its use in the critically ill patients, particularly in the hemodynamically unstable patient. We report on the safety and efficacy of propofol for use as an agent for urgent endotracheal intubation (UEI) in the critically ill patients. We reviewed the outcomes of 472 consecutive UEIs performed by a medical intensive care unit (ICU) team at a tertiary care hospital from November 2008 through November 2012. Outcome data were collected prospectively as part of an ongoing quality improvement project. Propofol was used as the sole sedative agent in 409 (87%) of the 472 patients. In 18 (4%) of the 472 patients, other agents (midazolam, lorazepam, or etomidate) were used in addition to propofol. Of the 472, 10 (2%) intubations were performed with a sedative agent other than propofol, and 35 (7%) of the 472 intubations were performed without any sedating agent. Endotracheal tube insertion was successful in all 472 patients. Complications of UEI in those patients who received propofol were as follows: desaturation (Sao 2 < 80%) 30 (7%) of the 427, hypotension (systolic blood pressure < 70 mm Hg) 19 (4%) of the 427, difficult intubation (>2 attempts) 44 (10%) of the 427, esophageal intubation 24 (6%) of the 427, aspiration 6 (1%) of the 427, and oropharyngeal injury 4 (1%) of the 427. There were no deaths. Average dose of propofol was 99 mg (standard deviation 7.39) per person. Our results compare favorably with the complication rate of UEI reported in the critical care and anesthesiology literature and indicate that propofol is a useful agent for airway management in the ICU.

Dexmedetomidine for a patient with Hallervorden–Spatz syndrome during magnetic resonance imaging: a case report

To the Editor: A 17-year-old boy of 160 cm height and 30 kg weight, diagnosed with Hallervorden–Spatz syndrome (HSS), also known as pantothenate kinase-associated neurodegeneration (PKAN), presented as severe opisthotonus, retrocollis, deteriorating intelligence level, thoracolumbar spine scoliosis, and tongue dystonia and was scheduled for brain magnetic resonance imaging (MRI) under general anesthesia. On preanesthesia examination, his heart rate was 127 bpm, respiratory rate 16/min, blood pressure 80/45 mm Hg, and oxygen saturation 95 % on room air. A loading dose of 1 lg/kg dexmedetomidine (Dexem; Themis Medicals, India) was infused over 15 min. With this, posturing and rigidity disappeared and the Ramsay sedation score (RSS) reached 5. Dexmedetomidine infusion was continued at a rate of 0.5 lg/kg/h using an MRIcompatible infusion pump (Perfusor; Space B/Braun, Germany) during MR imaging that lasted 1 h. Oxygen was administered through a face mask. He was hemodynamically stable throughout the procedure. An RSS of 2 was reached and opisthotonus posturing and rigidity reappeared 2 h after stopping the infusion. This case report highlights successful use of dexmedetomidine as a sole sedative agent for MRI in a patient with HSS. HSS is a rare autosomal recessive disorder caused by pantothenate kinase-associated neurodegeneration 2 (PKAN2) gene mutations resulting in accumulation of iron in the brain. The disease is also called neurodegeneration with brain iron accumulation (NBIA) [1]. Presenting features of HSS include progressive generalized dystonia involving the oromandibular muscles, rigidity, and choreoathetoid movement [1]. Airway management is critical during anesthesia in these patients. Oromandibular dystonia results in impaired swallowing, malnourishment, and high risk for pulmonary aspiration. Involvement of the pharyngeal muscles results in breathing difficulty and dynamic airway obstruction. These patients develop contractures and joint stiffness, including the jaw and cervical spine, leading to difficult airway. Associated mental retardation renders preoperative airway assessment difficult. Airway problems necessitate careful postoperative monitoring. MRI studies demand a quiet patient for better image quality. Severe dystonia necessitated sedation/general anesthesia in our patient. In a previous case report, volatile anesthetic was used to sedate a child with HSS, but postoperatively the patient developed airway obstruction requiring emergency intubation [2]. In our patient, we chose dexmedetomidine to provide sedation without respiratory depression [3]. As dystonia completely disappeared and an RSS of 5 was achieved after a bolus infusion of dexmedetomidine, we continued dexmedetomidine infusion during the MR imaging. Dexmedetomidine, by alpha-2 adrenergic modulation, induces prolonged nonREM sleep. As muscle atonia has been described during non-REM sleep, patients receiving dexmedetomidine infusion tend to be in a relaxed state with reduced muscle tone [4]. This mechanism could have suppressed the dystonia in our patient. Although propofol has been used in such patients, we avoided propofol as it causes dystonic reactions and opisthotonus [5]. Dystonia suppression by B. Madhusudhana Rao M. Radhakrishnan (&) Department of Neuroanesthesia, National Institute of Mental Health and Neuro Sciences, Bangalore 560029, Karnataka, India e-mail: mrks1974@gmail.com

Nonanesthesiologist-administered propofol sedation for colonoscopy is safe and effective

Propofol is increasingly being used in sedated colonoscopy. This paper assesses the safety and efficacy of nonanesthesiologist-administered propofol in a large series of colonoscopies. A prospective registry of consecutive American Society of Anesthetics (ASA) class I and II outpatients undergoing colonoscopy was carried out. Propofol, administered by a nurse under an endoscopist's supervision, was the sole sedative agent used. Of the 1000 patients (563 women/437 men, mean age 57, range 8-89 years) included in the study, 57.4% showed ASA I and 42.6% ASA II characteristics. The cecal intubation rate was 96.9%. 48.2% of the procedures were for therapeutic purposes. The mean propofol dose was 177 mg (range 50-590 mg). Doses correlated inversely with patient age (r=-0.38; P<0.001) and were lower in ASA II patients (P<0.001) and in diagnostic (rather than therapeutic) exams (P<0.001). The average recovery time (from extracting the colonoscope to patient discharge) was 18.6 min (range 4-75) and longer in ASA II patients (P=0.05). A pulse oximetry saturation of less than 90% and a decrease in systolic blood pressure of more than 20 mmHg were observed in 24 (2.4%) and 385 (35.8%) patients, respectively. Both events were more frequent in patients older than 65 years (P<0.05); the latter was more common in ASA II patients. Colonoscopy under endoscopist-controlled propofol sedation in low-risk patients is safe and effective, allowing for a complete exploration, although patients at least 65 years old and/or classified as ASA II are more likely to present a decrease in blood pressure and have a prolonged recovery time.

Superficial temporal artery–middle cerebral artery bypass using local anesthesia and a sedative without endotracheal general anesthesia

Superficial temporal artery (STA)-middle cerebral artery (MCA) bypasses have continually evolved, and new strategies have been advocated for reducing anesthetic or surgical morbidity and mortality. Further simplifying, and decreasing the invasiveness of, STA-MCA bypass by performing this operation without endotracheal general anesthesia was believed to be feasible in certain subsets of patients. The authors performed STA-MCA bypass using local anesthesia with a sedative in 10 patients with hemodynamically compromised occlusive cerebrovascular disease, as well as multiple comorbidities, between February 2010 and September 2011. The technique is based on the preoperative identification of the point at which the donor and recipient vessels are in closest proximity. Preoperative use of CT angiography allowed the authors to identify the target point precisely and use a minimally invasive procedure. All patients received dexmedetomidine as the sole sedative agent, together with scalp-blocking local anesthesia, with an unsecured airway. Successful STA-MCA bypass surgeries were achieved via a preselected minimally invasive approach in all cases. There was good hemodynamic stability throughout surgery. No airway or ventilation complications occurred, and no patients were converted to general anesthesia. Subjectively, patients tolerated the technique well with a high rate of satisfaction. There were no perioperative morbidities or deaths. Postoperative MR angiography confirmed a patent bypass in all patients. All patients remained symptom free and returned to normal daily life following the operation. This initial experience confirms the feasibility of performing STA-MCA bypass without endotracheal general anesthesia. This novel technique produced a high degree of patient satisfaction.

Administration of propofol for sedation of non-mechanically ventilated patients in non-critical care areas by anesthesia providers and non-anesthesia trained healthcare providers: a systematic review.

The use of propofol as a sedative in various outpatient settings is controversial. At the heart of this controversy is the use of propofol by non-anesthesia trained healthcare providers. To synthesize the best available evidence on the administration of propofol for sedation by anesthesia and non-anesthesia providers in spontaneous breathing patients in non-critical care settings. This review considered non-anesthesia trained and anesthesia trained healthcare providers administering propofol as the agent for sedation in patients of all ages who were not mechanically ventilated and were undergoing procedures for gastrointestinal endoscopy, cardiac catheterization, and procedural sedation for emergency room and radiology procedures.This review included studies where propofol was the sole sedative agent used by non-anesthesia trained, and formally trained anesthesia healthcare providers.This review considered as outcomes procedure time, return to baseline functioning, postoperative recovery time, mean amount of propofol administered, patient satisfaction, incidence of adverse hemodynamic and respiratory events, unplanned admission to hospital, and death.This review considered randomized controlled trials, cohort studies, case-control studies, and case series/report studies. The search strategy aimed to find both published and unpublished studies in English language beginning with the commercial use of propofol in 1989 through 2011. Search was performed across: CINAHL, MEDLINE, Nursing@Ovid, EMBASE, Elsevier Science Direct, Mednar, and Proquest. Studies were critically appraised by two independent reviewers for methodological validity prior to inclusion in the review using standardized critical appraisal instruments from the Joanna Briggs Institute. Data was extracted using the standardized data extraction tool from the Joanna Briggs Institute. Due to the heterogeneous nature of the interventions and outcome measurements, a meta-analysis was not possible; results are presented in a narrative summary. 9 studies were included in the review: 1 randomized controlled trial, 2 cohort studies, and 6 descriptive studies. In seven of the studies, non-anesthesia providers administered propofol, while two studies had anesthesia providers providing propofol sedation. Five studies reported procedure time. None of the studies reported a return to baseline functioning. Four studies reported postoperative recovery time. One study reported mean propofol dosage according to the two phases of the study, while another study in addition to reporting total and mean propofol dosages, differentiated propofol dosage according to ASA classification. Six of the studies reported average or mean propofol dosage, with one study also reporting the propofol induction dosage. Reporting of adverse hemodynamic and respiratory events varied in the studies. None of the studies reported unplanned admission to the hospital or death. The evidence suggests that anesthesia healthcare providers have the experience and training to safely administer propofol in non-critical care settings involving procedures in non-mechanically ventilated patients. The evidence also suggests that non-anesthesia trained healthcare providers can safely administer propofol sedation in low-risk patients who are not mechanically ventilated if they have received specialized training in the use of propofol sedation, are experienced in its administration, and follow a defined dosage protocol. The administration of propofol sedation by anesthesia providers can be safely administered in patients of all risk categories and depth of sedation.The administration of propofol sedation by non-anesthesia providers can be safely administered to low risk patients for moderate sedation providing the non-anesthesia provider is specially trained and experienced in the administration of propofol sedation while using a defined dosage protocol. Randomized controlled trials are needed to examine the propofol sedation by non-anesthesia healthcare providers in spontaneous breathing patients in non-critical care settings. The type of training required for safe administration of propofol in the outpatient settings should be explored.

Dexmedetomidine for monitored anesthesia care in patients undergoing liberation procedure for multiple sclerosis: An observational study

Background:It has been postulated that Multiple sclerosis (MS) stems from a narrowing in the veins that drain blood from the brain, known medically as chronic cerebrospinal venous insufficiency, or CCSVI. It has been proposed that balloon angioplasty should alleviate the symptoms of MS. This procedure is also known as The “Liberation Procedure”. Accordingly, a clinical study was undertaken to determine the effects of dexmedetomidine in patients undergoing the liberation procedure.Aims:To assess the effectiveness of dexmedetomidine in providing adequate sedation and pain relief for patients undergoing the liberation procedure.Settings and design:A prospective, nonrandomized observational study of 60 consecutive adult patients undergoing the liberation procedure under monitored anesthesia care (MAC) who will receive dexmedetomidine as an anesthetic agent.Methods:A total of 60 adult patients were enrolled in the study. Dexmedetomidine was administered to all patients in a loading dose of 1 mcg/kg, which was followed by a maintenance dose of 0.2–0.5 mcg/kg/h. The evaluation of quality of sedation was based on Ramsay Sedation and the quality of analgesia was assessed using the visual analog scale. The following parameters were measured continuously: heart rate, mean arterial pressure and hemoglobin oxygen saturation. Patients were asked to answer the question, “How would you rate your experience with the sedation you have received during surgery?” using a seven-point Likert-like verbal rating scale.Statistical analysis:Repeated measurements were analyzed by repeated measures ANOVA for HR and BP.Results:Most of our patients were satisfied with their sedation. In most of the patients, MAP and HR dropped after the bolus dose of dexmedetomidine, and the drop was statistically significant.Conclusions:Dexmedetomidine can be used as a sole sedative agent in patients undergoing the liberation procedure.