Of Alertness/Sedation Scale Research Articles

Comparison of dexmedetomidine/fentanyl with midazolam/fentanyl combination for sedation and analgesia during tooth extraction

Dexmedetomidine is an α2-adrenergic receptor agonist that causes minimal respiratory depression compared with alternative drugs. This study investigated whether combined dexmedetomidine/fentanyl offered better sedation and analgesia than midazolam/fentanyl in dental surgery. Sixty patients scheduled for unilateral impacted tooth extraction were randomly assigned to receive either dexmedetomidine and fentanyl (D/F) or midazolam and fentanyl (M/F). Recorded variables were patient preoperative anxiety scores, vital signs, visual analogue scale (VAS) pain scores, Observer's Assessment of Alertness/Sedation Scale (OAAS) scores after drug administration, surgeon and patient degree of satisfaction, and the duration of analgesia after surgery. The OAAS scores were significantly lower for patients administered D/F compared to those who received M/F. The duration of analgesia after the surgical procedure was significantly longer in patients who received D/F (5.3h) than in those who received M/F (4.1h; P=0.017). The number of surgeons satisfied with the level of sedation/analgesia provided by D/F was significantly higher than for M/F (P=0.001). Therefore, dexmedetomidine/fentanyl appears to provide better sedation, stable haemodynamics, surgeon satisfaction, and postoperative analgesia than midazolam/fentanyl during office-based unilateral impacted tooth extraction.

A Prospective, Randomized Comparative Study of Respiratory and Hemodynamic Monitoring during Colonoscopy using Remifentanyl Versus Propofol/Fentanyl

Objective: We hypothesized that remifentanil continuous infusion during colonoscopy in spontaneous respiration may give benefits in terms of quality of sedation and recovery compared to propofol, and that patients’ ventilatory drive and consciousness could be accurately evaluated by the continuous measurement of end-tidal CO2 (EtCO2), and of Bispectral Score (BIS) respectively. Methods: One-hundred and eighty patients scheduled for colonoscopy were randomized in two groups: 76 patients were included in Groupcontrol (propofol 0.5 mg/kg bolus plus infusion 1 mg/kg/h) and 78 patients in Gruopremi (0.5 mcg/Kg/1 min bolus plus infusion 0.08 mcg/kg/min, progressively reduced to 0.03 mcg/kg/min). Cardiovascular and respiratory variables were measured before induction and every 3 min throughout the procedure. Sedation level was estimated by BIS and Observer’s Assessment of Alertness/Sedation Scale (OAA/S). Respiratory function was evaluated by arterial oxygen saturation (SaO2) and EtCO2. Recovery from sedation and hospital discharge criteria were assessed by Modified Aldrete Score System (APRS) 30 min after colonoscopy completion. Results: Remifentanil was effective and well tolerated during colonoscopy. Hemodynamic parameters remained stable throughout the study steps in both groups. In Groupremi OAA/S and BIS score were higher (p<0.001), and EtCO2 (p<0.5) lower that in Groupcontrol. Recovery time was faster in the Groupremi (p<0.01). Conclusions: Our data show that analgosedation with remifentanil allowed to obtain a good quality colonoscopy without respiratory and hemodynamic impairment and with faster recovery than moderate sedation propofol/fentanyl. Moreover, BIS and EtCO2 monitoring proved to be well suited to evaluate the trend variations of patients’ sedation level and respiratory drive.

Efficacy of preoperative melatonin versus pregabalin on perioperative anxiety and postoperative pain in gynecological surgeries

BackgroundWe compared the efficacy of melatonin and pregabalin on perioperative anxiety and postoperative pain in patients undergoing laparoscopic gynecological surgeries.MethodsIn this randomized double-blind study, 40 patients, 25–35 yr undergoing gynecological surgeries were divided into 2 equal groups to receive either melatonin capsule 6 mg (Group M), or pregabalin capsule 150 mg (Group P) 1 h before induction of general anesthesia. Our primary outcome was preoperative acute anxiety level 1 h after drug administration, 1, 6, and 12 h after operation. The secondary outcomes were postoperative visual analog scale (VAS) for pain, analgesic consumption, sedation level using the inverted observer’s assessment of alertness/sedation scale (OAA/S) scale, and incidence of adverse effects.ResultsThe anxiety scores decreased significantly >50% after premedication in both groups compared to baseline values (p < 0.01) with no statistically significant difference between the two groups (30.4 ± 4.5 in group M versus 31.7 ± 4.2 in group P, p > 0.05). Postoperative VAS for pain, time for first analgesic demand and number of patients requiring postoperative analgesia did not differ between groups, and the sedation score was higher in melatonin group compared to pregabalin group 1 h after drug (3.45 ± 0.7 versus 1.95 ± 0.6, p < 0.001, respectively) and at all the subsequent readings postoperatively with equal incidence of adverse effects in both groups.ConclusionOral melatonin 6 mg or pregabalin 150 mg administered 1 h before operation had reduced perioperative anxiety and postoperative pain in patients undergoing gynecological surgeries, without untoward sedative effects in the pregabalin group compared to melatonin group.

Effect of propofol on the levels of neurotransmitters in normal human brain: A magnetic resonance spectroscopy study

Though widely used in anesthesia for many years, the mechanism underlying propofol anesthesia on human is not clear. Animal studies have already demonstrated that propofol functioned mainly by affecting neurotransmitters release. In our study, 10 healthy volunteers ranging from 20 to 40 years old were enrolled. With the help of target-controlled infusion pump, propofol was delivered intravenously. The target-controlled concentration (TCC) of propofol was gradually elevated from 0.5 to 3.0 μg/ml (for 6 steps with an increment of 0.5 μg/ml). During each step the Observer's Assessment of Alertness/Sedation Scale (OAA/S) was performed to evaluate asleep to awake/alert status. Magnetic resonance spectroscopy (MRS) was performed to evaluate neurotransmitters (choline compounds (Cho), creatine (Cr), glutamate (GLU), γ-aminobutyric acid (GABA) and N-acetyl aspartate (NAA)) changes in brains following propofol anesthesia. OAA/S scoring showed that when the TCCs of propofol were 0, 1.5 and 3.0 μg/ml, the volunteers were in awake, sedative and unconscious, respectively. Significantly down-regulated Cho and GLU, but up-regulated GABA was observed in unconscious state in all the detected regions. NAA was decreased in unconscious status only in the hippocampus and thalamus. There was no obvious change in Cr levels in any statuses or brain regions. Our results indicate that propofol has an impact on the levels of neurotransmitters such as NAA, GLU, GABA and Cho in normal human brain. During propofol anesthesia, enhancement of inhibition or suppression of excitation may each play key roles in different brain regions.

Correlation between the Narcotrend index, the cerebral state index and the predicted effect site concentration during different state of consciousness in elderly patients with target controlled infusion of propofol

To study the correlation between the Narcotrend index, cerebral state index and predicted effect site concentration during different state of consciousness in the absence of surgery in elderly patients with target controlled infusion of propofol. Twenty patients aged from 65-75 years categorized as ASA class I - II who were scheduled to undergo general surgery under general anesthesia with target controlled infusion of propofol were recruited. During the target controlled infusion of propofol, the propofol infusion was set at an initial effect site concentration of 0.5 mg/L and increased by 0.5 mg /L every 5 min until the modified observer's assessment of alertness / sedation scale (OAA/S) values of zero. The predicted effect site concentration of propofol, the values of CSI and NCT were recorded and the sedation level was examined by the modified OAA/S every 20 s. The predicted effect site concentrations of propofol in target controlled infusion (TCI) system were recorded when they increased by more than 0.1 mg/L. The predicted effect site concentrations of propofol and the values of NCT and CSI at LVC and LOC of the patients were recorded. There was a good linear correlation between NCT and the predicted effect site concentration of propofol (R2 = 0. 867, P < 0.01), as well as that between CSI and the predicted effect site concentration of propofol (R2 = 0.893, P < 0.01). The predicted effect site concentrations of propofol at LVC was (1.56 +/- 0.13) mg/L while the values of NCT was 74.00 +/- 4.69 and CSI 69.82 +/- 5.47. The predicted effect site concentrations of propofol at LOC was (2.15 +/- 0.27) mg/L while the values of NCT and CSI were 63.30 +/- 7.50 and 58.78 +/- 6.90 respectively. All of the values of NCT, CSI and the predicted effect site concentrations had a good linear correlation with OAA/S. There was a negative correlation between OAA/S and the predicted effect site concentration. At the same time, there was a positive correlation between OAA/S and NCT as well as that between OAA/S and CSI. And the correlation coefficients were - 0.968, 0.938, 0.940 respectively (P < 0.01). The values of NCT were higher significantly than that of CSI in different degree of LOC (P < 0.01). During elder people's target controlled infusion of propofol, LVC and LOC occur within a definite range of predicted effect site concentrations. There is a good linear correlation between NCT, CSI and the predicted effect site concentrations of propofol. For the elders, both NCT and CSI reflect the sedation level of propofol. Although there is a significant correlation between NCT and CSI, a deviation does exist in a certain range. Therefore a simple 1:1 transfer from NCT to CSI is inadequate.

Abstract 3018: Sedation of Elderly Patients Undergoing Coronary Arteriography Does Not Result in Adverse Outcomes and Improves Postprocedural Care

Background: Elderly patients are undergoing invasive cardiac diagnostic procedures more frequently. Preprocedural sedation is often prescribed, intraprocedural medications administered, and appropriate concern raised regarding post procedure delirium and adverse consequences in the elderly. The objective of this prospective randomized study was to investigate the effect of premeditation on new onset delirium and procedural care. Methods: Patients ≤ 70 years old and scheduled for elective cardiac catheterization were screened for enrollment. All patients underwent a mini mental status exam (MMSE) and delirium assessment using confusion assessment method (CAM) prior to the procedure and repeated at 4 hours and prior to discharge or the next morning. Patients were randomly assigned to receive either diphenhydramine and diazepam (25 mg / 5 mg po) or no premedication. Patient cooperation during the procedure and ease of post-procedure management by nursing staff was measured using Visual Analog Scale (VAS). The degree of alertness was assessed immediately on arrival to the floor, at one and two hours using Observer’s Assessment of Alertness/Sedation Scale (OAA/S). Results: Total of 93 patients enrolled in the study, of which 47 patients received premedication prior to the procedure. The mean age was 77 ± 4.2 years, 56% were male. The baseline mean MMES was similar in each group (27.6± 1.4 in premedication group versus 28.17±1.4 in patients without premedication). Patients with premedication were less alert immediately and at one hour after arrival on the floor (p&lt;0.01), but no patient in either group developed delirium after the procedure as measured by CAM. The ease of procedure was greater, pain medication requirement lower and nursing reported an improvement with patient management after the procedure in the premedicated group (all p&lt;0.05). Conclusion : Premedication did not cause delirium or confusion in elderly patients undergoing cardiac catheterization. The reduced pain medication requirement, perceived procedural ease and post procedure management favors premedication in elderly patients under going cardiac catheterization.

Postoperative Results after Desflurane or Sevoflurane Combined with Remifentanil in Morbidly Obese Patients

This randomized prospective study with blinded postanesthesia care unit (PACU) observers compared the recovery profiles in morbidly obese patients who received sevoflurane or desflurane for maintenance of anesthesia in combination with a remifentanil target controlled infusion (TCI). 50 morbidly obese patients scheduled for laparoscopic gastric banding were included to receive BIS-guided sevoflurane or desflurane anesthesia with BIS-triggered inhalation boli in combination with remifentanil TCI. In the PACU, the following recovery scores were investigated: Modified Aldrete score, a modified Observers' Assessment of Alertness/Sedation Scale (OAA/S), pain numerical rating scale (NRS), oxygen saturation (SpO(2)) and postoperative nausea and vomiting (PONV). OAA/S and NRS pain scores showed a similar evolution in both groups from the moment of PACU admission up to 120 minutes after admission. In both groups, patients showed no serious hypoxemia during PACU stay. Incidence of PONV was shorter lasting in the sevoflurane group compared to the desflurane group. No clinically relevant difference was found in recovery in the PACU between morbidly obese patients anesthetized with desflurane or sevoflurane. Both agents resulted in satisfactory recovery in morbidly obese patients.

Development and Validation of the Clinician Satisfaction with Sedation Instrument (CSSI)

Background: Currently there are no validated or universally accepted clinician satisfaction scores in use that are specific to gastrointestinal endoscopic sedation. Validated clinician-rated measures are needed to evaluate satisfaction with different sedation regimens and sedation delivery systems during various endoscopic procedures such as EGD and colonoscopy. Methods: The CSSI was developed, based on literature review and interviews with clinicians, to measure clinician perceptions of satisfaction with sedation delivery and related problems associated with sedation during endoscopic procedures. The CSSI consists of 16 items covering 2 domains: sedation administration and recovery/post procedure. The CSSI has an additional 5 global satisfaction items. Items are rated on a 7-point Likert scale ranging from 1 (very satisfied) to 7 (very dissatisfied). A psychometric evaluation study was conducted in 5 gastroenterology practices throughout the United States consisting of 22 physicians. Patients who recently underwent elective outpatient colonoscopy or EGD were chosen. Factor analysis was used to derive the final 16 item version. Internal consistency reliability was assessed and validity was assessed by examining the association between the CSSI scores with patient satisfaction ratings (PSSI), and ratings of patient alertness (100 mmVAS), difficulty of procedure (0-10), and Observer's Assessment of Alertness/Sedation Scale (OAA/S) during the procedure. Results: There were 118 study patients who mostly women (59%), white (88%), and with mean age of 57.5 ± 15.7 yrs. Internal consistency reliabilities of CSSI total and subscale scores were all >0.93. The correlations between the total scores and sub scale scores of the CSSI and patient rated satisfaction were moderate (r = 0.18 to 0.26, p < 0.05). The correlations between CSSI recovery/post procedure scores and the patient alertness VAS was 0.25 (p < 0.05). Global level of difficulty ratings were correlated (r = 0.38, p < 0.01) with sedation administration and (r = 0.33, p < 0.01) with the CSSI total score. CSSI total and subscale scores were correlated −0.27 to −0.32 (all p < 0.05) with OAA/S scores during the procedure. Conclusion: The CSSI is a reliable and valid measure of clinician satisfaction with sedation delivery, monitoring and post-procedure recovery for endoscopic procedures. This evaluation tool can be used to standardize clinician assessment of procedural sedation satisfaction for colonoscopy and EGD in future sedation trials.

Comparison of entropy and narcotrend indexes during TCI of propofol

Objective To compare the entropy with narcotrend indexes during the period of propofol induction and tracheal intubation. Methods Eighteen patients of ASA Ⅰ-Ⅱ were inducted by target-controlled infusion (TCI) of propofol, target was set according to the effect compartment concentration (Ce), stepwise increasing (0.5 mg/L) method was used, after the final Ce (6 mg/L) was achieved, orotracheal intubation was performed. Observer’s assessment of alertness/sedation scale (OAA/S) was used to detect the changes of consciousness. Response entropy (RE), state entropy (SE), stages and values of narcotrend (NT), MAP and HR were recorded at each step of Ce, and the time-point of before, immediately, and 1min to 10min after tracheal intubation. Results Scores of OAA/S scale were decreased with the increases of Ce of propofol. Ce according to OAA/S score of 2 and 0 were 2.0±0.6 mg/L and 2.2±0.6 mg/L, respectively. Values of RE, SE, and NT were decreased gradually with the increases of Ce, especially the NT values. The Spearman rank correlation coefficient between Ce and RE, SE, NT values were -0.83,-0.80 and -0.86 (P0.01), respectively. RE, SE, and NT values at the point of 2.0 mg/L of Ce were significantly lower than those of baseline. Compared to the values of before intubation, RE and SE of immediately after intubation were significantly increased (P0.05), MAP and HR at the time-point of 1min and 2min after intubation were also increased(P0.05), however, values and stages of NT had no statistically significant changes during the period of intubation. Conclusions Both Entropy and Narcotrend indexes can reflect promptly the changes of consciousness during the induction of propofol, and they have a close correlation with the effect compartment concentration of propofol, especially the stages and values of NT. Entropy index (RE and SE) and hemodynamic indictors (MAP and HR), but Narcotrend index (stages and values), can reflect the stimulation of tracheal intubation.

Bispectral analysis during deep sedation of pediatric oral surgery patients

Bispectral (BIS) analysis uses electroencephalogram information from a forehead electrode to calculate an index score (0 to 100; 0 = coma; 90 to 100 = awake). This index score correlates with the level of alertness in anesthetized patients. Classically, sedation has been monitored with clinical sedation scales such as the Observers Assessment of Alertness Sedation Scale (OAA/S), Modified Ramsey Scale, or a Visual Analog Scale (VAS). Our objective was to determine the correlation between clinical sedation scales and BIS index in pediatric patients undergoing sedation in an outpatient oral surgery setting. Prospective cohort study of patients aged 2 to 17 years undergoing sedation in an outpatient oral surgery office. Sedation was performed in the customary manner with the addition of BIS monitoring. Three clinical sedation scores (OAA/S: 5 to 1; 5 = awake, 1 = unresponsive; Modified Ramsey: 1 to 6; 1-2 = awake, 6 = unresponsive; VAS: 0 to 10; 0 = awake, 10 = unresponsive) were assigned every 5 minutes by an investigator blinded to the BIS index. Data were analyzed using a repeated measures linear regression model. Sixteen subjects undergoing oral surgery, ages 4.5 years to 17 years, were enrolled, mean age 12.6 years +/- 4.3 years (standard deviation). Patients received methohexital in addition to 1 or more of the following: nitrous oxide, fentanyl, or midazolam. The results of the longitudinal regression analysis showed a highly significant association between the sedation scales and the BIS index. The BIS monitor may be a useful adjunct in monitoring pediatric patients receiving sedation in the outpatient setting.

Low-dose ketamine with clonidine and midazolam for adult day care surgery

Low-dose ketamine with clonidine and midazolam for adult day care surgery

End‐tidal Carbon Dioxide Monitoring during Procedural Sedation

Abstract. Objective: To prospectively determine whether end‐tidal carbon dioxide (ETCO2) monitors can detect respiratory depression (RD) and the level of sedation in emergency department (ED) patients undergoing procedural sedation (PS). Methods: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS. Patients were monitored for vital signs, depth of sedation per the physician by the Observer's Assessment of Alertness/Sedation scale (OAA/S), pulse oximetry, and nasal‐sample ETCO2 during PS. Respiratory depression was defined as an oxygen saturation &lt;90%, an ETCO2 &gt;50 mm Hg, or an absent ETCO2 waveform at any time during the procedure. The physician also determined whether protective airway reflexes were lost during the procedure and assisted ventilation was required, or whether there were any other complications. Rates of RD were compared with the physician assessment of airway loss and between agents using chi‐square statistics. Spearman's rho analysis was used to determine whether there was a correlation between ETCO2and the OAA/S score. Results: Seventy‐four patients were enrolled in the study. Forty (54.1%) received methohexital, 21 (28.4%) received propofol, ten (13.5%) received fentanyl and midazolam, and three (4.1%) received etomidate. Respiratory depression was seen in 33 (44.6%) patients, including 47.5% of patients receiving methohexital, 19% receiving propofol (p = 0.008), 80% receiving fentanyl and midazolam, and 66.6% receiving etomidate. No correlation between OAA/S and ETCO2 was detected. Eleven (14.9%) patients required assisted ventilation at some point during the procedure, all of whom met the criteria for RD. Pulse oximetry detected 11 of the 33 patients with RD. Post‐hoc analysis revealed that all patients with RD had an ETCO2 &gt;50 mm Hg, an absent waveform, or an absolute change from baseline in ETCO2 &gt;10 mm Hg. Conclusions: There was no correlation between ETCO2and the OAA/S score. Using the criteria of an ETCO2 &gt;50 mm Hg, an absolute change &gt;10 mm Hg, or an absent waveform may detect subclinical RD not detected by pulse oximetry alone. The ETCO2 may add to the safety of PS by quickly detecting hypoventilation during PS in the ED.

Depth of sedation in children undergoing computed tomography: validity and reliability of the University of Michigan Sedation Scale (UMSS)

Safe care of sedated children requires ongoing assessment of the depth of sedation to permit early recognition of progression to over-sedation. This study evaluated the validity and reliability of the University of Michigan Sedation Scale (UMSS) as a measure of sedation during procedures. The UMSS is a simple observational tool that assesses the level of alertness on a five-point scale ranging from 1 (wide awake) to 5 (unarousable with deep stimulation). Thirty-two children aged 4 months to 5 yr (mean 1.5 yr), sedated for computed tomography (CT), were studied prospectively. The CT nurse assessed sedation using the UMSS before sedative administration and every 10 min thereafter. The child was videotaped during each assessment, and segments were edited and their order was randomized. Four nurses blinded to sedative administration viewed the segments and scored sedation using the UMSS. One of these nurses also scored sedation using a visual analogue scale (VAS) and another using the Observer's Assessment of Alertness/Sedation Scale (OAAS). To examine the test-retest reliability, 75 randomly selected video segments were viewed and scored on a second occasion. Changes in scores from baseline to discharge supported construct validity (P<0.0001). Criterion validity was demonstrated by significant correlations between the UMSS and the VAS and OAAS. There was good interobserver agreement between blinded observers' scores for each level of sedation and at discharge, and between blinded observers and the CT nurse for scores of 0 and 1 (lighter levels of sedation), but less agreement for scores 2 and 3 (deeper sedation) and discharge scores. Test-retest reliability was supported by agreement in the observers' UMSS scores. The UMSS is a simple, valid and reliable tool that facilitates rapid and frequent assessment and documentation of depth of sedation in children.

Remifentanil conscious sedation during regional anaesthesia for carotid endarterectomy: rationale and safety.

to prospectively evaluate the safety and efficacy of remifentanil during regional anaesthesia for carotid endarterectomy. twenty-eight consecutive patients underwent carotid endarterectomy with combined superficial and deep cervical plexus block supplemented with continuous intravenous 0.04 microg.kg(-1).min(-1)remifentanil infusion. Depth of sedation was monitored using the Observer's Assessment of Alertness/Sedation Scale (OAA/S). The degree of pain, discomfort and anxiety was self-assessed by the patients using a horizontal visual analogue scale. all patients experienced adequate comfort and analgesia. No local anaesthetic supplementation was necessary. No patient had a OAA/S score lower than 4 (with 5=awake/alert to 1=asleep). Respiratory depression did not occur. Selective shunting was required in four cases. No patient was converted to general anaesthesia. There were no permanent neurological deficits, cardiopulmonary complications or deaths. remifentanil as a supplement to regional anaesthesia for carotid endarterectomy, provides comfort and analgesia without hampering mental status evaluation.