Assessing sedation with regional anesthesia: inter-rater agreement on a modified Wilson sedation scale

The Conditions for Ethical Chemical Restraints

The practice of medicine frequently involves the unconsented restriction of liberty. The reasons for unilateral liberty restrictions are typically that being confined, strapped down, or sedated are necessary to prevent the person from harming themselves or others. In this paper, we target the ethics of chemical restraints, which are medications that are used to intentionally restrict the mental states associated with the unwanted behaviors, and are typically not specifically indicated for the condition for which the patient is being treated. Specifically, we aim to identify the conditions under which chemical restraints are ethically permissible. It is wrong to assume that what is morally true of physical restraints is also true of chemical restraints. Our aim is thus to identify the conditions under which chemical restraints are permissible while distinguishing these conditions from those of the application of physical restraints.

Efficacy of peritonsillar infiltration with dexmedetomidine versus tramadol in comparison to placebo for pain control and sedation after tonsillectomy in pediatric patients: A randomized clinical trial

Objective

This article aimed to assess the efficacy of peritonsillar infiltration with dexmedetomidine-ropivacaine versus tramadol-ropivacaine for pain control and sedation after tonsillectomy in pediatric patients.

Materials and Methods

This double-blind clinical trial recruited 99 eligible children (4-8 years old) undergoing tonsillectomy and assigned to three block-randomized groups, receiving dexmedetomidine-ropivacaine (group A), tramadol-ropivacaine (group B), or placebo-ropivacaine (group C). The vital signs included blood pressure, heart rate, and SaO2 before anesthesia induction, during surgery at regular intervals until 24 h after surgery. The duration of surgery and recovery, complications, and analgesic consumption were recorded and pain scores were measured by Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and Oucher scales as well as sedation scores by the Wilson sedation scale. Data were analyzed within SPSS 20 at a significance level of 0.05.

Results

The lowest pain scores were measured by the CHEOPS scale in the dexmedetomidine-ropivacaine group (P < 0.05). Statistically significant difference was observed in the CHEOPS pain score between the first two groups at 30 min, 1 h, 2 h, and 4 h after surgery (P < 0.01). The differences were revealed in the Oucher pain assessments among all groups from the time of recovery to four postoperative hours (P < 0.05), with the lowest in the dexmedetomidine-ropivacaine group whose sedation score was greater during recovery and 5 min after surgery (P < 0.05). Subjects in tramadol group had six cases of dizziness and nausea, while no side effects were observed in two other groups (P < 0.05). Only seven participants receiving dexmedetomidine required acetaminophen, but 29 in the tramadol group and all in the placebo group demanded to receive acetaminophen (P = 0.001).

Conclusion

The authors concluded that dexmedetomidine as an adjuvant to ropivacaine has better performance in local infiltration for intra- and post-tonsillectomy analgesia and postoperative sedation, without any special side effects (like the placebo group), and that it hence is recommended to be used for local infiltration during tonsillectomy.

Caudal Morphine in Pediatric Patients: A Comparison of Two Different Doses in Children Undergoing Infraumbilical Surgery - A Prospective, Randomized, Double-Blind Study

Background

One of the most feared symptoms of any disease is PAIN. It is a complex phenomenal experience, especially in children. Various methods and medications have been administered through different routes. Regional anesthesia produces marvelous postoperative analgesia and cessation of stress response in infants and children. Caudal epidural analgesia is the most acceptable and popular method of providing intra- and postoperative analgesia for abdominal, perineal, and lower limb surgeries in children. The use of preservative-free morphine as an adjunct to ropivacaine increases the quality and duration of analgesia despite the various side effects. Various articles use various doses of morphine as an adjuvant in caudal epidural analgesia. Hence, we conducted the study to compare the two dosages of morphine that is 20 μg.kg-1 and 30 μg.kg-1 of caudal epidural morphine for infraumblical surgeries with regard to its efficacy and safety and side effect profiles.

Materials and Methods

The study is a prospective, randomized, double-blinded study. Sixty patients were divided into two groups. Group A: 20 μg.kg-1 of morphine was added to 0.2% ropivacaine 1 mL.kg-1 and the solution was made. Group B: 30 μg.kg-1 of morphine was added to 1 mL.kg-1 of 0.2% ropivacaine. Heart rate, systolic blood pressure, diastolic blood pressure, SPO2, pain score, and sedation score were recorded immediately, after 15 min, 30 min, 45 min, 1 h, 2 h, 4 h, 8 h, 12 h, 16 h, 18 h, and 24 h were recorded.

Results

The mean duration of analgesia is similar in both groups (P = 0.011). The mean duration was 20.517 ± 1.9143 h in Group A and 22.233 ± 1.6853 h in Group B. Children with the requirement of one dose of rescue analgesia in Group A was 83.3% which was higher than Group B being 66.7%. Children with no analgesic requirement were 16.7% in Group A and 33.3% in Group B. The incidence of side effects was more in Group B (8 [26.7%] children with nausea and vomiting; 1 [3.3%] children with urinary retention) than in Group A (2 [6.6%] children with nausea and vomiting.

Conclusion

From the above observations, it can be concluded that morphine of less dosage (20 μg.kg-1) when added to 0.2% ropivacaine for the caudal epidural block has better efficacy than morphine of higher dosage (30 μg.kg-1) as the duration of analgesia is similar with decreased incidence of side effects.

Tools Are Needed to Promote Sedation Practices for Mechanically Ventilated Patients

Suboptimal sedation practices continue to be frequent, although the updated guidelines for management of pain, agitation, and delirium in mechanically ventilated (MV) patients have been published for several years. Causes of low adherence to the recommended minimal sedation protocol are multifactorial. However, the barriers to translation of these protocols into standard care for MV patients have yet to be analyzed. In our view, it is necessary to develop fresh insights into the interaction between the patients' responses to nociceptive stimuli and individualized regulation of patients' tolerance when using analgesics and sedatives. By better understanding this interaction, development of novel tools to assess patient pain tolerance and to define and predict oversedation or delirium may promote better sedation practices in the future.

Comparison of Postoperative Pain and Analgesia Requirement among Diabetic and Nondiabetic Patients undergoing Lower Limb Fracture Surgery - A Prospective Observational Study

Background:

Diabetic patients usually experience neuropathic pain and have a decreased response to opioids. Fractures are acute conditions and as such, they are very painful. No data is available related to fracture and postoperative pain in diabetics.

Aim:

This study was conducted to evaluate postoperative pain and analgesics requirement among diabetic and nondiabetic patients undergoing lower limb fracture surgery and the effect of glycosylated hemoglobin (HbA1c) on the postoperative pain.

Setting and Design:

This was a prospective observational study, conducted on 80 patients comprising of nondiabetic and diabetic, scheduled for elective lower limb fracture surgery under spinal anesthesia.

Materials and Methods:

HbA1c was done in all the patients who were included in the study. Postoperative Visual Analog Scale (VAS) and analgesic consumption were assessed by an anesthesiologist blinded to the diabetic or nondiabetic status of the patients. VAS was assessed every 2^nd hourly, for 24 h and rescue analgesia was given if the VAS was ≥4 and record was maintained. Sedation scores and adverse effects were also recorded postoperatively.

Statistical Analysis:

The Chi-square test was used for the analysis of categorical variables and Student's t-test was used for continuous variables.

Results:

Diabetic group of patients had a significantly high VAS score with P ≤ 0.05. Rescue analgesics requirement was significantly different in two groups with diabetic patients requiring more supplementation of analgesia with a P = 0.025. The overall patient satisfaction was lesser in diabetic group (P = 0.004). There was statistically significant correlation between glycosylated hemoglobin and VAS at 2^nd, 16^th, 18^th, 20^th, 22^nd, and 24^th h.

Conclusion:

Postoperative pain and analgesic requirement was significantly higher in diabetic patients with lower limb fracture. Glycosylated hemoglobin had good correlation with higher VAS.

A Comparative Study of Periarticular Infiltration with Dexmedetomidine versus Ketorolac as an Additive to Ropivacaine after Total Knee Arthroplasty: A Prospective, Randomized Double-Blind Study

Background:

Periarticular infiltration (PAI) analgesia has been found to be an effective analgesia modality after total knee arthroplasty (TKA). Dexmedetomidine has many beneficial effects on postoperative analgesia by different routes, but studies on PAI are lagging.

Aims and Objectives:

In this study, we compared postoperative analgesia after PAI with dexmedetomidine versus ketorolac as an additive to ropivacaine after TKA.

Setting and Design:

This is a prospective, randomized, double-blind study conducted on 75 patients belonging to American Society of Anesthesiologists I to III, undergoing total knee arthroplasty, of either gender, belonging to American Society of Anesthesiologists I to III.

Materials and Methods:

After institutional ethics committee approval and written informed consent, patients were randomly allocated into three groups. Group C (n = 25) received cocktail of 60 mL ropivacaine (0.25%) infiltration with adrenaline 5 mL (0.1 mg.mL⁻¹), Group D (n = 25) received additive dexmedetomidine 1 ug.kg⁻¹ to above cocktail, and Group K (n = 25) received ketorolac 30 mg. Postoperatively pain by Visual Analog Scale, vitals, total duration of analgesia, need for rescue analgesia, sedation, patient satisfaction, mobilization time, and complications were recorded.

Statistical Analysis:

The Statistical Package for the Social Sciences version 20 was used for statistical analysis. Analysis of variance has been used to find the significance of study parameters between the three groups of patients. P < 0.05 was considered statistically significant.

Results:

Postoperative pain score was lesser in the ketorolac group (1.52 ± 0.71, P = 0.001) than the other two groups. Duration of analgesia was more with ketorolac (343.00 ± 144.45, P < 0.001) compared with the other two groups, and epidural activation timings (462 ± 235.84) were significantly delayed in Group K compared to Group C and Group D. There was no significant difference in mobilization time, patient satisfaction, and complications between the three groups.

Conclusion:

Ketorolac was a better additive to ropivacaine than dexmedetomidine for postoperative analgesia after TKA.

Comparison of remifentanil concentrations with and without dexmedetomidine for the prevention of emergence cough after nasal surgery: a randomized double-blinded trial

Background

Preventing emergence cough after nasal surgery is critical. Emergence cough can provoke immediate postoperative bleeding, which leads to upper airway obstruction. In the present study, we compared the effect-site concentration (Ce) of remifentanil to prevent emergence cough after propofol anesthesia for nasal surgery when remifentanil was or was not combined with dexmedetomidine.

Methods

Forty-seven patients with propofol-remifentanil anesthesia for nasal surgery were randomly assigned to a dexmedetomidine group (Group D, n = 23) or a saline group (Group S, n = 24). Group D and Group S were infused with dexmedetomidine (0.5 μg/kg) and saline, respectively, for 10 min before the completion of surgery. A predetermined Ce of remifentanil was infused until extubation. Remifentanil Ce to prevent cough in 50 and 95% of patients (EC₅₀ and EC₉₅) was estimated using modified Dixon’s up-and-down method and isotonic regression. Hemodynamic and recovery parameters were recorded.

Results

The EC₅₀ of remifentanil Ce was significantly lower in Group D than in Group S (2.15 ± 0.40 ng/mL vs. 2.66 ± 0.36 ng/mL, p = 0.023). The EC₉₅ (95% CI) of remifentanil Ce was also significantly lower in Group D [2.75 (2.67–2.78) ng/mL] than in Group S [3.16 (3.06–3.18) ng/mL]. Emergence and recovery variables did not differ between the two groups.

Conclusion

The remifentanil EC₅₀ to prevent cough after propofol-remifentanil anesthesia was significantly lower (approximately 19%) when a combination of remifentanil and 0.5 μg/kg dexmedetomidine was used than when remifentanil infusion alone was used in patients undergoing nasal surgery. Therefore, the Ce of remifentanil may be adjusted to prevent emergence cough when used in combination with dexmedetomidine.

Trial registration

ClinicalTrials.gov (NCT03622502, August 9, 2018).

Identification and evaluation of observational measures for the assessment and/or monitoring of level of consciousness in adult palliative care patients: A systematic review for I-CAN-CARE

BACKGROUND

The use of observational measures to assess palliative care patients' level of consciousness may improve patient care and comfort. However, there is limited knowledge regarding the validity and reliability of these measures in palliative care settings.

AIM

To identify and evaluate the psychometric performance of observational level of consciousness measures used in palliative care.

DESIGN

Systematic review; PROSPERO registration: CRD42017073080.

DATA SOURCES

We searched six databases until November 2018, using search terms combining subject headings and free-text terms. Psychometric performance for each identified tool was appraised independently by two reviewers following established criteria for developing and evaluating health outcome measures.

RESULTS

We found 35 different levels of consciousness tools used in 65 studies. Only seven studies reported information about psychometric performance of just eight tools. All other studies used either ad hoc measures for which no formal validation had been undertaken (n = 21) or established tools mainly developed and validated in non-palliative care settings (n = 37). The Consciousness Scale for Palliative Care and a modified version of the Richmond Agitation-Sedation Scale received the highest ratings in our appraisal, but, since psychometric evidence was limited, no tool could be assessed for all psychometric properties.

CONCLUSION

An increasing number of studies in palliative care are using observational measures of level of consciousness. However, only a few of these tools have been tested for their psychometric performance in that context. Future research in this area should validate and/or refine the existing measures, rather than developing new tools.

Relationship between brain computed tomography findings and bispectral index score in patients presenting with head trauma

OBJECTIVE:

Head trauma is one of the most important emergency health problems both in the world and in our country. The objective in our study is to (i) state the correlation between the findings of bispectral index score (BIS) and computed tomography (CT), which are used to evaluate the level of consciousness of patients with isolated head trauma, and (ii) investigate objective results about the patient’s level of consiousness/alertness according to the CT modality, which is used frequently.

METHODS:

This prospective study was carried out between 03.01.2014 and 09.01.2014 in the emergency department of Fatih Sultan Mehmet Education and Research Hospital. The average BIS scores were correlated with the Glasgow Coma Scale (GCS) point, the Canadian CT Head Rule major and minor criteria, and the pathologic findings in CT imaging. The patients’ demographic features, vital signs at admission, and arrival times at the hospital were investigated.

RESULTS:

In our study, 64 (31.7%) patients were female, and 138 (68.3%) patients were male. The mean BIS scores were 84.99±11.20 (86.05) and 93.78±3.80 (95.05) in patients with and without CT pathologies, respectively. The correlation between CT pathology and BIS scores was statistically significant: BIS scores were lower in patients with CT pathologies (p=0.001; p<0.01). There was a statistically significant positive correlation between the BIS and GCS scores (45.6%) (p<0.05).

CONCLUSION:

We showed that most head traumas occur after dangerous accidents, and according to the results, we can predict that males are more frequently affected than females. There was a statistically significant positive correlation between BIS scores and GCS points. In our study, the BIS scores were statistically significantly lower in patients with CT pathology than in patients without. We can predict that if the BIS score of the patient is low, then there will be the presence of pathology on CT imaging.

Palliative Sedation in Terminal Cancer Patients Admitted to Hospice or Home Care Programs: Does the Setting Matter? Results From a National Multicenter Observational Study

CONTEXT

Few studies regarding palliative sedation (PS) have been carried out in home care (HC) setting. A comparison of PS rate and practices between hospice (HS) and HC is also lacking.

OBJECTIVES

Comparing HC and HS settings for PS rate, patient clinical characteristics before and during PS, decision-making process, and clinical aspects of PS.

METHODS

About 38 HC/HS services in Italy participated in a multicenter observational longitudinal study. Consecutive adult cancer patients followed till death during a four-month period and undergoing PS were eligible. Symptom control and level of consciousness were registered every eight hours to death.

RESULTS

About 4276 patients were screened, 2894 followed till death, and 531 (18%) underwent PS. PS rate was 15% in HC and 21% in HS (P < 0.001). Principal refractory symptoms were delirium (54%) and dyspnea (45%), respectively, more common in HC (P < 0.001) and HS (P = 0.03). Informed consent was not obtained in 72% of patients but achieved by 96% of families. Midazolam was the most used drug (94% HS vs. 75% HC; P < 0.001) mainly by continuous infusion (74% HC vs. 89% HS; P < 0.001). PS duration was less than 48 hours in 67% of patients. Hydration during PS was less frequent in HC (27% vs. 49%; P < 0.001). In the eight hours before death, consciousness level was unrousable to mild physical stimulation in 81% and symptom control complete in 89% of cases.

CONCLUSION

Our results show feasibility of PS in HC and HS and suggest setting differences in rates, indications, and practice of PS, possibly related to patients' selection or care organization.

Predicting effective remifentanil concentration in 95% of patients to prevent emergence cough after laryngomicroscopic surgery

Smooth emergence or cough prevention is a clinically important concern in patients undergoing laryngomicroscopic surgery (LMS). The purpose of this study was to estimate the effective concentration of remifentanil in 95% of patients (EC95) for the prevention of emergence cough after LMS under propofol anesthesia using the biased coin design (BCD) up-down method.A total of 40 adult patients scheduled to undergo elective LMS were enrolled. Anesthesia induction and maintenance were performed with target-controlled infusion of propofol and remifentanil. Effective effect-site concentration (Ce) of remifentanil in 95% of patients for preventing emergence cough was estimated using a BCD method (starting from 1 ng/mL with a step size of 0.4 ng/mL). Hemodynamic and recovery profiles were observed after anesthesia.According to the study protocol, 20 patients were allocated to receive remifentanil Ce of 3.0 ng/mL, and 20 patients were assigned to receive lower concentrations of remifentanil, from 1.0 to 2.6 ng/mL. Based on isotonic regression with a bootstrapping method, EC95 (95% CI) of remifentanil Ce for the prevention of emergence cough from LMS was found to be 2.92 ng/mL (2.72-2.97 ng/mL). Compared with patients receiving lower concentrations of remifentanil, the incidence of hypoventilation before extubation and extubation time were significantly higher in those receiving remifentanil Ce of 3.0 ng/mL. However, hypoventilation incidence after extubation and staying time in the recovery room were comparable between the 2 groups.Using a BCD method, the EC95 of remifentanil Ce for the prevention of emergence cough was estimated to be 2.92 ng/mL (95% CI: 2.72-2.97 ng/mL) after LMS under propofol anesthesia.

A Comparison of Oral Midazolam-ketamine, Dexmedetomidine-fentanyl, and Dexmedetomidine-ketamine Combinations as Sedative Agents in Pediatric Dentistry: A Triple-Blinded Randomized Controlled Trial

Introduction:

It is common to encounter a patient who is anxious to the magnitude that precludes the possibility of provision of dental treatment. This study aims to evaluate and compare the sedative effect of oral combinations of midazolam-ketamine (MK), dexmedetomidine-fentanyl (DF), and dexmedetomidine-ketamine (DK) in a group of uncooperative children requiring dental treatment.

Methodology:

This was a prospective, randomized, triple-blind study where 36 children who were 3–9 year old with American Society of Anesthesiologists –I status and presenting early childhood caries were randomly assigned to: Group A – 0.3 mg/kg of M and 5 mg/kg K, Group B – 2 ug/kg of D with 3 ug/kg of F, and Group C – 2ug/kg of D with 5 mg/kg of K in 1 mL honey. Patients' blood pressure, heart rate, and oxygen saturation were recorded from the start of the procedure till discharge. Patients' behavior, sedation status, and wake-up behavior were evaluated with Modified Observer Assessment of Alertness and Sedation Scale and ease of treatment completion by Houpt scale.

Results:

Hemodynamic changes were statistically insignificant in all three groups. 72.8% of patients in Group A and 58.3% of patients in Group B were successfully sedated during treatment. Behavior improvement was seen in all three groups during treatment with statistically insignificant difference in behavior scores produced by Group C. Ease of treatment completion was moderately better with Group A.

Conclusion:

Oral DK has a comparable sedative property with oral MK combination. Oral DF promises to be a potential sedative agent for children due to its successful anxiolysis.

A Comparative Study of Analgesic Efficacy of Intrathecal Buprenorphine with Ultrasound-Guided Transversus Abdominis Plane Block for Postcesarean Delivery Analgesia

BACKGROUND

Women undergoing cesarean (CS) delivery present a unique set of challenges to the anesthetist in terms of postoperative pain management. This study was conducted to compare the analgesic efficacy of intrathecal buprenorphine (ITB) with ultrasound-guided transversus abdominis plane (TAP) block in post-CS delivery pain.

METHODOLOGY

A prospective randomized comparative study of sixty American Society of Anesthesiologists physical status I and II pregnant patients divided into two groups of thirty each as ITB group and TAP block group after satisfying the inclusion criteria.

RESULTS

In the present study, demographic data were comparable between both groups. The time to first analgesic request was significantly longer in ITB group (389.67 ± 90.78 min) compared to TAP group (669.17 ± 140.65 min) and was statistically significant, P < 0.001. The mean paracetamol consumption in the first 24 h was higher in the TAP group (3.5 g) compared to the ITB group (1.13 g) and was statistically significant, P < 0.0001, and the mean tramadol consumed in first 24 h was higher in the TAP (46.66 mg) group as compared to the ITB group (16.66 mg) and was statistically significant, P < 0.001. The mean visual analog scale scores assessed at 4, 6, 12, and 24 h was higher in the TAP group and was statistically significant, P < 0.001.

CONCLUSIONS

Our study showed that patients receiving ITB for post-CS pain management reported longer duration of analgesia, lower pain scores, and lower analgesic consumption during the first 24 h. The benefits of neuraxial opiates are significant and far outweigh the side effects.

Postoperative analgesia with dexmedetomidine in interscalene block. Comparative study

INTRODUCTION

Dexmedetomidine prolongs sensory block of ropivacaine. Our objective was to study whether this extension would produce better postoperative pain control compared to that produced by clonidine in patients undergoing arthroscopic shoulder.

MATERIALS AND METHODS

Study comparative, longitudinal, controlled, randomized into 3 groups. Control group I: ropivacaine 0.75% clonidine group II: 0.75% ropivacaine plus clonidine 1mg/kg group iiidexmedetomidine: 0.75% ropivacaine more dexmedetomidine 1mg/kg. Interscalene block single dose ultrasound-guided. Sensory and motor blockade, pain intensity, sedation level, heart rate, respiratory rate, blood pressure at 6, 12 and 24hours was measured.

RESULTS

Pain intensity at 6hours in groups I and II moderate to severe pain, mild pain group iii. At 12hours the groups IIand II showed moderate to severe pain by more than 60% of patients, and in group iiionly 10%. At 24hours I and II group 20% of patients they continued to moderate pain.

CONCLUSION

The prolonged interscalene block produced by dexmedetomidine provided better postoperative pain control during the first 24hours.

Comparative evaluation of dexmedetomidine and midazolam-ketamine combination as sedative agents in pediatric dentistry: A double-blinded randomized controlled trial

Background:

Pharmacological methods have been used as an adjunct to enhance child cooperativeness and facilitate dental treatment.

Objective:

Purpose of this study was to evaluate and compare the effect of sedation by intranasal dexmedetomidine and oral combination drug midazolam–ketamine in a group of children with uncooperative behavior requiring dental treatment.

Materials and Methods:

This was a prospective, randomized, double-blind study that included patients 3–9 years old with American Society of Anesthesiologists-I status. About 36 children presenting early childhood caries were randomly assigned to one of three groups studied: Group MK received intranasal saline and oral midazolam (0.5 mg/kg) with ketamine (5 mg/kg) mixed in mango juice; Group DX received intranasal dexmedetomidine (1 μg/kg) and oral mango juice; and Group C received intranasal saline and oral mango juice. Patients' heart rate, blood pressure, and oxygen saturation were recorded before, during, and at the end of the procedure. Patients' behavior, sedation status, and wake up behavior were evaluated with modified observer assessment of alertness and sedation scale. Ease of treatment completion was evaluated according to Houpt scale.

Results:

Hemodynamic changes were statistically insignificant in Group MK and Group DX. About 75% patients in Group MK were successfully sedated as compared to 53.9% Group DX and none of the patients in Group C. Ease of treatment completion was better with Group MK as compared to Group DX and least with Group C. Around 50% patients in Group MK had postoperative complications.

Conclusion:

Oral midazolam–ketamine combination and intranasal dexmedetomidine evaluated in the present study can be used safely and effectively in uncooperative pediatric dental patients for producing conscious sedation.

Postoperative analgesia in children: A comparison of three different doses of caudal epidural morphine

Background and Aims:

Caudal epidural block is the most commonly used neuraxial block in children. Morphine has been used as a caudal additive for more than three decades. The aim of our study was to evaluate the efficacy and duration of analgesia of three different doses of caudal epidural morphine (CEM), and to find out the incidence of side effects.

Material and Methods:

This study was conducted on 75 patients of American Society of Anesthesiologists grades I and II, aged 2-12 years, undergoing lower abdominal and urogenital surgeries. Patients were randomly allocated to one of the three groups according to the dose of morphine. Group I received 30 μg/kg, group II 50 μg/kg, and group III 70 μg/kg. Heart rate, blood pressure, oxygen saturation, electrocardiogram, pain score, sedation score, duration of analgesia, and side-effects were noted.

Results:

The mean duration of analgesia was 8.63 h in group I, 13.36 h in group II and 19.19 h in group III. Respiratory depression was noted in three patients in group III. One patient in group I had itching. One patient each in groups I, II, and III had nausea/vomiting.

Conclusion:

CEM significantly prolongs the duration of analgesia, though with a higher dose the risk of respiratory depression should always be kept in mind.

The efficacy and safety of epidural dexmedetomidine and clonidine with bupivacaine in patients undergoing lower limb orthopedic surgeries

BACKGROUND AND AIMS

Alpha (α-2) adrenergic agonists have both analgesic and sedative properties when used as an adjuvant in regional anesthesia. A prospective randomized double-blind study was carried out to evaluate the efficacy of epidural route and to compare the efficacy and clinical profile of dexmedetomidine and clonidine as an adjuvant to bupivacaine with special emphasis on their quality of analgesia, sedation and the ability to provide the smooth intra-operative and postoperative course.

MATERIAL AND METHODS

The study was conducted in prospective, randomized and double-blind manner. It included 60 American Society of Anesthesiologists Class I and II patients undergoing lower limb surgery under epidural anesthesia. Patients were randomly divided into Group A receiving 0.5% isobaric bupivacaine 15 ml with dexmedetomidine 1 μg/kg and Group B receiving 0.5% isobaric bupivacaine 15 ml with clonidine 2 μg/kg epidurally. Onset and duration of sensory and motor blocks, duration of analgesia, sedation, and adverse effects were assessed.

RESULTS

Demographic data, surgical characteristics cardio-respiratory parameters, side-effect profile were comparable and statistically not significant in both the groups. However, sedation scores with dexmedetomidine were better than clonidine and turned out to be statistically significant. The onset times for sensory and motor blocks were significantly shorter in Group A as compared to Group B. The duration of analgesia and motor block was significantly longer in A Group as compared to Group B.

CONCLUSION

Dexmedetomidine is a superior neuraxial adjuvant to bupivacaine when compared to clonidine for early onset of analgesia, superior intra-operative analgesia, stable cardio-respiratory parameters, prolonged postoperative analgesia and providing patient comfort.

Efficacy Outcome Measures for Procedural Sedation Clinical Trials in Adults: An ACTTION Systematic Review

Successful procedural sedation represents a spectrum of patient- and clinician-related goals. The absence of a gold-standard measure of the efficacy of procedural sedation has led to a variety of outcomes being used in clinical trials, with the consequent lack of consistency among measures, making comparisons among trials and meta-analyses challenging. We evaluated which existing measures have undergone psychometric analysis in a procedural sedation setting and whether the validity of any of these measures support their use across the range of procedures for which sedation is indicated. Numerous measures were found to have been used in clinical research on procedural sedation across a wide range of procedures. However, reliability and validity have been evaluated for only a limited number of sedation scales, observer-rated pain/discomfort scales, and satisfaction measures in only a few categories of procedures. Typically, studies only examined 1 or 2 aspects of scale validity. The results are likely unique to the specific clinical settings they were tested in. Certain scales, for example, those requiring motor stimulation, are unsuitable to evaluate sedation for procedures where movement is prohibited (e.g., magnetic resonance imaging scans). Further work is required to evaluate existing measures for procedures for which they were not developed. Depending on the outcomes of these efforts, it might ultimately be necessary to consider measures of sedation efficacy to be procedure specific.

Sedation in hypoalbuminemic geriatric patients under spinal anesthesia in hip surgery. Midazolam or Propofol?

Objectives:

To compare midazolam and propofol sedation in hypoalbuminemic geriatric patients under spinal anesthesia in hip surgery with bispectral index monitoring.

Methods:

This prospective and randomized study was completed in the Department of Anesthesiology, Okmeydani Training and Research Hospital, Istanbul, Turkey between February 2013 and December 2014. Sixty patients undergoing elective hip surgery under spinal anesthesia in the geriatric age group with albumin levels below 3 g/dl were randomly divided into Group I and Group II. After administration of spinal block, Group I were given 0.05 mg/kg bolus midazolam, and then 0.02-0.1 mg/kg/hr dose infusion was begun. In Group II, 1 mg/kg bolus propofol was given within 10 minutes, and then 1-3 mg/kg/hr infusion was begun. The systolic arterial pressure, diastolic arterial pressure, mean arterial pressure, heart rate, peripheral oxygen saturation values, respiratory rate, and Wilson’s 5-stage sedation score were recorded at 15-minute intervals. At the end of the operation, the recovery time and surgeon satisfaction were recorded.

Results:

The recovery times for patients in Group I were found to be longer than in Group II (p<0.05). The respiration rate in patients in Group I at the start of surgery, 15th minute of surgery, and after surgery were lower than in Group II (p<0.05).

Conclusion:

We conclude that propofol is more reliable in terms of hemodynamic stability than midazolam, as it causes less respiratory depression and faster recovery in the propofol group.

Determination of EC95 of remifentanil for smooth emergence from propofol anesthesia in patients undergoing transsphenoidal surgery

BACKGROUND

In patients undergoing pituitary surgery using a transsphenoidal approach, anesthesia emergence should be smooth with minimal coughing. Recent studies demonstrated that a target-controlled infusion of remifentanil effectively suppresses coughing induced by the endotracheal tube. We investigated the EC95 of remifentanil for smooth emergence without coughing from propofol anesthesia in patients undergoing transsphenoidal hypophysectomy.

MATERIALS AND METHODS

A total of 41 patients undergoing transsphenoidal hypophysectomy, aged 20 to 65 years, with an ASA physical status of I or II, were enrolled. For all participants, anesthesia was induced and maintained with a target-controlled infusion of remifentanil and propofol using predicted effect-site concentration (Ce). A biased coin design up-and-down sequential allocation and isotonic regression method were used to determine the remifentanil EC95 to prevent emergence coughing. In addition, we observed recovery profiles after anesthesia.

RESULTS

According to the study design, 19 patients received remifentanil 2.6 ng/mL Ce and 22 patients received a lower Ce, ranging from 1.0 to 2.2 ng/mL. The EC95 of remifentanil to prevent coughing was estimated as 2.51 ng/mL (95% confidence interval, 2.28-2.57 ng/mL). Despite the exclusion of 1 case because of delayed emergence, 17 of 18 patients receiving 2.6 ng/mL of remifentanil had bradypnea (<10 breaths/min) until 3 minutes after extubation. However, end-tidal carbon dioxide was maintained below 55 mm Hg during anesthetic emergence and respiratory rate recovered within 20 minutes of admission to the postanesthetic care unit.

CONCLUSIONS

The EC95 of remifentanil for smooth emergence from anesthesia was 2.51 ng/mL after transsphenoidal hypophysectomy.

Does the type of anesthetic agent affect remifentanil effect-site concentration for preventing endotracheal tube-induced cough during anesthetic emergence? Comparison of propofol, sevoflurane, and desflurane

STUDY OBJECTIVE

To investigate whether the type of anesthetic agent administered affects the antitussive effect of remifentanil.

DESIGN

Prospective randomized study.

SETTING

Operating room of a university hospital.

PATIENTS

78 ASA physical status 1 and 2 women, aged 20 to 65 years, who were scheduled to undergo a thyroidectomy.

INTERVENTIONS

Patients were randomly assigned to three groups to receive anesthesia with propofol (Group P), sevoflurane (Group S), or desflurane (Group D). The main anesthetics were titrated to maintain a target Bispectral Index for hypnosis of 40 to 60. Remifentanil was administered via effect-site target-controlled infusion (TCI). To determine the effective remifentanil effect-site concentration (Ce) to suppress coughing in each group, the up-and-down sequential allocation design was used.

MEASUREMENTS

The half maximal effective concentration (EC50) values of remifentanil for preventing coughing in the groups were estimated using isotonic regression and compared among the groups.

MAIN RESULTS

The EC50 of remifentanil for cough suppression in Group P [1.60 ng/mL (98.3% CI, 0.92-1.75 ng/mL)] was statistically lower than in Group D [1.96 ng/mL (98.3% CI, 1.81-2.50 ng/mL)]. The EC50 in Group S was 1.75 ng/mL (98.3% CI, 1.39-2.13 ng/mL), which was higher than in Group P and lower than in Group D, but did not differ significantly from either group.

CONCLUSIONS

Remifentanil administration for cough suppression during emergence should be customized to the anesthetic agent.

The validity, reliability, responsiveness and applicability of observation sedation-scoring instruments for use with adult patients in the emergency department: a systematic literature review

AIM

This paper reports a systematic literature review examining the range of published observational sedation-scoring instruments available in the assessment, monitoring and titration of continuous intravenous sedation to critically ill adult patients in the Emergency Department, and the extent to which validity, reliability, responsiveness and applicability of the instruments has been addressed.

BACKGROUND

Emergency nurses are increasingly responsible for the ongoing assessment, monitoring and titration of continuous intravenous sedation, in addition to analgesia for the critically ill adult patient. One method to optimise patient sedation is to use a validated observational sedation-scoring tool. It is not clear however what the optimal instrument available is for use in this clinical context.

METHODS

A systematic literature review methodology was employed. A range of electronic databases were searched for the period 1946-2013. Search terms incorporated "sedation scale", "sedation scoring system", "measuring sedation", and "sedation tool" and were used to retrieve relevant literature. In addition, manual searches were conducted and articles retrieved from those listed in key papers. Articles were assessed using the Critical Appraisal Skills Program (CASP) making sense of evidence tools.

RESULTS

A total of 27 observational sedation-scoring instruments were identified. Sedation-scoring instruments can be categorised as linear or composite, the former being the most common. A wide variety of patient behaviours are used within the instruments to measure depth and quality of patient sedation. Typically sedation-scoring instruments incorporated three patient behaviours, which were then rated to generate a numerical score. The majority of the instruments have been subjected to validity and reliability testing, however few have been examined for responsiveness or applicability.

CONCLUSIONS

None of the 27 observational sedation-scoring instruments were designed or trialled within ED. The Richmond Agitation and Assessment Scale was identified as most suitable to be trialled prospectively within an Australian ED.

Bispectral index score and observer's assessment of awareness/sedation score may manifest divergence during onset of sedation: Study with midazolam and propofol

Background:

Correlation between the clinical and electroencephalogram-based monitoring has been documented sporadically during the onset of sedation. Propofol and midazolam have been studied individually using the observer's assessment of awareness/sedation (OAA/S) score and Bispectral index score (BIS). The present study was designed to compare the time to onset of sedation for propofol and midazolam using both BIS and OAA/S scores, and to find out any correlation.

Methods:

A total of 46 patients (18-60 years, either sex, American Society of Anesthesiologists (ASA) I/II) posted for infraumbilical surgeries under spinal anaesthesia were randomly allocated to receive either injection propofol 1 mg/kg bolus followed by infusion 3 mg/kg/h (Group P, n=23) or injection midazolam 0.05 mg/kg bolus followed by infusion 0.06 mg/kg/h (Group M, n=23). Spinal anaesthesia was given with 2.5 ml to 3.0 ml of 0.5% bupivacaine heavy. When sensory block reached T6 level, sedation was initiated. The time to reach BIS score 70 and time to achieve OAA/S score 3 from the start of study drug were noted. OAA/S score at BIS score 70 was noted. Data from 43 patients were analyzed using SPSS 12 for Windows.

Results:

Time to reach BIS score 70 using propofol was significantly lower than using the midazolam (P<0.05). Time to achieve OAA/S score 3 using propofol was comparable with midazolam (P=0.358).

Conclusion:

A divergence exists between the time to reach BIS score 70 and time to achieve OAA/S score 3 using midazolam, compared with propofol, during the onset of sedation.

Dexmedetomidine and clonidine in epidural anaesthesia: A comparative evaluation

Efforts to find a better adjuvant in regional anaesthesia are underway since long. Aims and objectives are to compare the efficacy and clinical profile of two α-2 adrenergic agonists, dexmedetomidine and clonidine, in epidural anaesthesia with special emphasis on their sedative properties and an ability to provide smooth intra-operative and post-operative analgesia. A prospective randomized study was carried out which included 50 adult female patients between the ages of 44 and 65 years of (American Society of Anaesthesiologists) ASAI/II grade who underwent vaginal hysterectomies. The patients were randomly allocated into two groups; ropivacaine + dexmedetomidine (RD) and ropivacaine + clonidine (RC), comprising of 25 patients each. Group RD was administered 17 ml of 0.75% epidural ropivacaine and 1.5 μg/kg of dexmedetomidine, while group RC received admixture of 17 ml of 0.75% ropivacaine and 2 μg/kg of clonidine. Onset of analgesia, sensory and motor block levels, sedation, duration of analgesia and side effects were observed. The data obtained was subjected to statistical computation with analysis of variance and chi-square test using statistical package for social science (SPSS) version 10.0 for windows and value of P < 0.05 was considered significant and P < 0.0001 as highly significant. The demographic profile, initial and post-operative block characteristics and cardio-respiratory parameters were comparable and statistically non-significant in both the groups. However, sedation scores with dexmedetomidine were better than clonidine and turned out to be statistically significant (P < 0.05). The side effect profile was also comparable with a little higher incidence of nausea and dry mouth in both the groups which was again a non-significant entity (P > 0.05). Dexmedetomidine is a better neuraxial adjuvant compared to clonidine for providing early onset of sensory analgesia, adequate sedation and a prolonged post-operative analgesia.

A Randomised, Placebo-controlled Trial of the Effects of Preoperative Pregabalin on Pain Intensity and Opioid Consumption following Lumbar Discectomy

BACKGROUND

Pregabalin has been shown to have analgesic effect in acute pain models. The primary objective was to examine the efficacy a single dose of pregabalin, would have on morphine consumption following lumbar discectomy.

METHODS

With ethical approval a randomized, placebo-controlled prospective trial was undertaken in 32 patients (ASA I-II, 18-65 years) with radicular low back pain for > 3 months undergoing elective lumbar discectomy. Patients received either oral pregabalin 300 mg (PG Group) or placebo (C Group) one hour before surgery. Pain intensity, the accumulative morphine consumption and adverse effects were recorded for 24 hours following surgery. Functional, psychological and quantitative sensory testing were also assessed.

RESULTS

Fourteen patients out of the 32 recruited were randomized to receive pregabalin. Morphine consumption was reduced (absolute difference of 42.3%) between groups with medium effect size. (Mann-Whitney; U = 52.5, z-score= 2.84, P = 0.004, r = 0.14). This was not associated with a significant difference in the incidence of adverse effects between the two groups. The median pain intensity (VAS) on movement was not significantly different between groups.

CONCLUSIONS

A single pre-operative dose of pregabalin (300 mg) did not result in a reduction in pain intensity compared to placebo in this patient cohort but the significant reduction in morphine consumption suggests that a fixed peri-operative dosing regime warrants investigation.

General anesthesia occurs frequently in elderly patients during propofol-based sedation and spinal anesthesia

STUDY OBJECTIVE

To test the hypothesis that sedation in elderly patients is often electrophysiologically equivalent to general anesthesia (GA).

DESIGN

Prospective, observational study.

SETTING

Operating room of a university medical center.

PATIENTS

40 elderly patients (>or=65 yrs of age) undergoing hip fracture repair with spinal anesthesia and propofol-based sedation.

INTERVENTIONS

In the routine practice group (RP; n = 15), propofol sedation was administered per the usual routine of the anesthesiologist. In the targeted sedation group (TS; n = 25), sedation was titrated to an observer's assessment of alertness/sedation (OAA/S) score of 4 (ie, lethargic in response to name called) to 5 (ie, awake and alert).

MEASUREMENTS

Both patient groups underwent processed electroencephalographic monitoring using bispectral index (BIS) intraoperatively. BIS levels were compared between groups to determine amount of surgical time spent in GA (BIS <or= 60).

MAIN RESULTS

In the RP group, subjects spent 32.2% of surgical time at BIS levels consistent with GA. Although averaged BIS values during surgery increased from (mean +/- SD) 71 +/- 16 to 88 +/- 9 (P < 0.001), GA was still observed during 5% of surgical time in the TS group. Overall, 13 of 15 (87%) RP group patients and 11 of 25 (44%) TS group patients (P < 0.010) experienced some period of GA.

CONCLUSIONS

BIS levels consistent with GA occur frequently in elderly patients during propofol-based sedation for spinal anesthesia. Altering routine practice such that sedation is titrated to a targeted clinically-determined sedation level reduces - but does not eliminate - this incidence.

Sedation depth during spinal anesthesia and the development of postoperative delirium in elderly patients undergoing hip fracture repair

OBJECTIVE

To determine whether limiting intraoperative sedation depth during spinal anesthesia for hip fracture repair in elderly patients can decrease the prevalence of postoperative delirium.

PATIENTS AND METHODS

We performed a double-blind, randomized controlled trial at an academic medical center of elderly patients (>or=65 years) without preoperative delirium or severe dementia who underwent hip fracture repair under spinal anesthesia with propofol sedation. Sedation depth was titrated using processed electroencephalography with the bispectral index (BIS), and patients were randomized to receive either deep (BIS, approximately 50) or light (BIS, >or=80) sedation. Postoperative delirium was assessed as defined by Diagnostic and Statistical Manual of Mental Disorders (Third Edition Revised) criteria using the Confusion Assessment Method beginning at any time from the second day after surgery.

RESULTS

From April 2, 2005, through October 30, 2008, a total of 114 patients were randomized. The prevalence of postoperative delirium was significantly lower in the light sedation group (11/57 [19%] vs 23/57 [40%] in the deep sedation group; P=.02), indicating that 1 incident of delirium will be prevented for every 4.7 patients treated with light sedation. The mean +/- SD number of days of delirium during hospitalization was lower in the light sedation group than in the deep sedation group (0.5+/-1.5 days vs 1.4+/-4.0 days; P=.01).

CONCLUSION

The use of light propofol sedation decreased the prevalence of postoperative delirium by 50% compared with deep sedation. Limiting depth of sedation during spinal anesthesia is a simple, safe, and cost-effective intervention for preventing postoperative delirium in elderly patients that could be widely and readily adopted.

[Sedation in surgical procedures using regional anesthesia in adult patients: results of a survey of Spanish anesthesiologists]

OBJECTIVE

To analyze the frequency and methods of sedation used in the context of regional anesthesia in adults by means of a national survey.

MATERIAL AND METHODS

We carried out a survey of participants at the courses of an anesthesiology training organization (Fundación Europea de Enseñanza en Anestesiología), held in Spain in 2006. The survey questionnaires asked about indications for sedation used during surgery under regional anesthesia as well as the form of administration, follow-up, and complications.

RESULTS

A total of 375 questionnaires were sent out and 185 responses were received (49.3%). Sedation is always used to accompany regional anesthesia by 69.2% of the respondents; 13.5% of them discuss the technique to be used with the patient and come to an agreement. The same type of sedation, regardless of the regional block performed, is used by 49.2% of respondents, and 64.3% use a scale to evaluate the level of sedation. The most favored sedation technique is continuous infusion, followed by target controlled infusion and boluses on demand. The most commonly used technique is sedation with bolus injections. Sixty percent use a single agent and 38.9% use combinations. The most commonly reported adverse effects are variability of patient response (53.5%) and respiratory complications (27%). In cases of ineffective regional blockade, 49.2% of those surveyed switch to general anesthesia.

CONCLUSIONS

Sedation is very often used to complement regional anesthesia in adult patients. Even though continuous infusion is considered to be the most appropriate form of administration, the most commonly used form is injection of boluses. Sedation with a single drug is used more frequently than drug combinations. Variability of individual response is the complication most commonly reported by the respondents.

Sedation and regional anaesthesia in the adult patient

This review discusses sedation for regional anaesthesia in the adult population. The first section deals with general aspects of sedation and shows that the majority of patients receiving sedation for regional anaesthesia are satisfied and would choose it again. Methods of assessing the level of sedation are discussed with emphasis on clinical measures. The pharmacology of the drugs involved in sedation is discussed, with propofol and remifentanil appearing to be the combination of choice for sedation in regional anaesthesia. The techniques for administering sedation are discussed and replacement of the traditional repeated boluses or continuous infusion with pharmacokinetic and patient-controlled systems is supported. Patient satisfaction studies suggest that patient-controlled systems are preferred.

Variation of bispectral index under TIVA with propofol in a paediatric population

BACKGROUND

In this prospective observational study, we aim to explore the relationship between age and bispectral index (BIS) values at different plasma concentrations of propofol.

METHODS

Fifty children aged from 3 to 15 yr were included. Anaesthesia was induced using a target-controlled infusion of propofol with the Kataria pharmacokinetic model together with a bolus of remifentanil followed by a continuous infusion rate at 0.2 microg kg(-1) min(-1). Target plasma propofol concentration was initially stabilized to 6 microg ml(-1) and continued for 6 min. The target was then decreased and stabilized to 4 microg ml(-1) and then to 2 microg ml(-1). BIS values, plasma propofol concentration, and EEG were continuously recorded. In order to explore the relationship between variations in propofol concentration and the EEG bispectrum, we used a multiple correspondence analysis (MCA). Results are shown in median (range).

RESULTS

We found no statistical difference between BIS values with propofol 6 microg ml(-1) [23 (12-40)] and 4 microg ml(-1) [28 (9-67)]. At 2 microg ml(-1), BIS was significantly different [52 (24-71)], but a significant correlation between the age of children and BIS values was found (r2=0.66; P<0.01). There was little change in children's position between 6 and 4 microg ml(-1) in the structure model of the MCA. From 4 to 2 microg ml(-1), the position of children moved only on axis 2.

CONCLUSIONS

These results showed the difficulty to interpret BIS values because of the absence of significant change for higher plasma propofol concentration variation or because of the link with age for the lower plasma concentration.

Sedation Analgesia during Office-Based Plastic Surgery Procedures: Comparison of Two Opioid Regimens

BACKGROUND

The combination of sedative and analgesic drugs is increasingly being used during minimally invasive surgery. The authors compared the clinical efficacy of two different fentanyl regimens, in combination with midazolam, for sedation analgesia in patients undergoing office-based plastic surgery procedures under local anesthesia.

METHODS

One-hundred patients were randomized into two groups of 50 subjects each. Group F1 received a fentanyl bolus of 0.7 microg/kg before infiltration with local anaesthetics; group F2 received the same bolus plus 0.6 microg/kg fentanyl every 45 minutes. All patients received a midazolam bolus of 0.05 mg/kg plus continuous infusion 0.08 mg/kg per hour.

RESULTS

High-quality analgesia was obtained in every group, without significant differences between the two fentanyl regimens. Group F2 was associated with lower intraoperative mean blood pressure and SpO2 values compared with group F1. No differences were detected between the two groups in perioperative side effects or postoperative pain.

CONCLUSION

Higher doses of opioid did not improve the quality of perioperative patient comfort but acted synergistically with the sedative drugs, amplifying the hemodynamic and respiratory side effects.

Pitfalls and challenges when assessing the depth of hypnosis during general anaesthesia by clinical signs and electronic indices

The objective of this article was to review the present methods used for validating the depth of hypnosis. We introduce three concepts, the real depth of hypnosis (DHreal), the observed depth of hypnosis (DHobs), and the electronic indices of depth of hypnosis (DHel-ind). The DHreal is the real state of hypnosis that the patient has in a given moment during the general anaesthesia. The DHobs is the subjective assessment of the anaesthesiologist based on clinical signs. The DHel-ind is any estimation of the depth of hypnosis given by an electronic device. The three entities DHreal, DHobs and DHel-ind should in the ideal situation be identical. However, this is rarely the case. The correlation between the DHobs and the DHel-ind can be affected by a number of factors such as the stimuli used for the assessment of the level of consciousness or the administration of analgesic agents or neuro muscular blocking agents. Opioids, for example, can block the response to tactile and noxious stimuli, and even the response to verbal command could vanish, hence deeming the patient in a lower depth of hypnosis than the real patient state. The DHel-ind can be disturbed by the presence of facial muscular activity. In conclusion, although several monitors and clinical scoring scales are available to assess the depth of hypnosis during general anaesthesia, care should be taken when interpreting their results.

Dexmedetomidine for awake carotid endarterectomy: efficacy, hemodynamic profile, and side effects

: A randomized, double-masked, placebo-controlled study was designed to compare dexmedetomidine as a primary sedative agent with a commonly used drug combination in patients undergoing awake carotid endarterectomy (CEA). Sixty-six patients undergoing CEA (ASA II-IV) were randomly assigned to receive either dexmedetomidine (total dose of 97.5 +/- 54.7 mcg) or normal saline (control). Supplemental doses of midazolam, fentanyl, and/or propofol were administered as deemed necessary by the anesthesiologist. An observer blinded to the study drug assessed sedation level (Observer's Assessment of Alertness-Sedation [OAA/S] scale). The primary outcomes were defined as the number of patients with an OAA/S score of 4 intraoperatively and an OAA/S score of 5 postoperatively. The authors also compared cardiorespiratory parameters, intra- and postoperative side effects, and complications. Chi-square tests were used to analyze the primary endpoints. All secondary parameters were analyzed using the Wilcoxon rank sum test. Three patients in the dexmedetomidine group (10%) had an OAA/S score of 4 at all four time points assessed intraoperatively, while no patient in the control group had a score of 4 at all the time points considered. Thirteen patients in the dexmedetomidine group had a score of 4 at three or more time points (42%) compared with six patients (19%) in the control group. Four patients in the control group (13%) and one patient in the dexmedetomidine group (3%) did not achieve a score of 4 at any of the four critical intraoperative time points (chi for association = 9.9, P < 0.05; chi for a trend = 8.6, P < 0.004, with the trend favoring dexmedetomidine). More patients in the control group required treatment with metoprolol (26% vs. 6%, P = 0.04) and labetalol (48% vs/ 6%, P < 0.01). Plasma levels of norepinephrine were significantly lower in the dexmedetomidine group during and after surgery compared with the control group. Six patients (19%) in the dexmedetomidine group required intra-arterial shunts, while only two patients (6%) required shunts in the control group (P = 0.16). These data show that the use of dexmedetomidine in patients undergoing awake CEA resulted in fewer fluctuations from the desired sedation level. Patients receiving dexmedetomidine required less antihypertensive therapy compared with the midazolam/fentanyl/propofol combination. The effect of dexmedetomidine on cerebrovascular circulation in the study population needs further investigation.