The patient-controlled sedation (PCS) allows for rapid individualized titration of sedative drugs. Propofol has been the most widely used IV adjuvant, during the monitored anesthesia care (MAC). This study was designed to compare the sedation quality, side effect and recovery of the propofol alone, and propofol-remifentanil combination, using PCS for breast biopsy.
Seventy five outpatients, undergoing breast biopsy procedures with local anesthesia, were randomly assigned to receive propofol alone (group P), propofol-25 ug/ml of remifentanil (group PR25), and propofol-50 ug/ml of remifentanil (group PR50), using PCS. Pain visual analogue scores (VAS) and digit symbol substitution test (DSST), Vital signs, bi-spectral index (BIS) and observer assessment of alertness and sedation (OAA/S) score were recorded.
Apply/Demand ratio in the group PR50 had a significant increase over the other groups (P < 0.05). The incidence of excessive sedation and dizziness were significantly more frequent in the group PR50 (P < 0.05). BIS and OAA/S score significantly decreased in the group PR25, PR50 at 15 min after the operation, the end of surgery (P < 0.05). At 5 min after the start of PCS, patients in the group PR25 and PR50 gave significantly less correct responses on the DSST than that of the group P (P < 0.05).
Compared with the propofol alone, intermittent bolus injection of propofol-remifentanil mixture could be used, appropriately, for the sedation and analgesia during MAC. The group PR25 in a low dose of remifentanil has more advantages in terms of sedation and satisfaction because of the group PR50's side effects.
Monitored anesthesia care; Patient-controlled sedation; Propofol; Remifentanil
The purpose of the present study was to evaluate the correlation among the trial number of in vitro fertilization (IVF), preoperative anxiety, and propofol requirement for conscious sedation. One hundred and twenty six Korean women undergoing oocyte retrieval were enrolled. The target-controlled infusion by the anesthesiologist was conducted with initial target propofol concentration of 2.5 microg/mL, which was manipulated until the sedation score 3 and desired clinical end point were achieved. A weak correlation was observed between visual analogue scale (VAS) anxiety and the dose of propofol required for the induction of conscious sedation (r=0.22, p=0.0192). A weak correlation was also found between VAS anxiety and the sedation time needed to reach the proper conscious sedation level for the procedure (r=0.181, p=0.0484). Multiple regression analysis showed that VAS anxiety, preoperative baseline prolactin level, and cortisol level had statistically significant effects on the propofol induction dose for target controlled conscious sedation. We concluded that the induction dose and time requirements for propofol in anesthesiologist-controlled conscious sedation be modified based on the preoperative anxiety level and the baseline blood concentration of stress hormone, cortisol and prolactin.
AIM: To compare deep sedation with propofol-fentanyl and midazolam-fentanyl regimens during upper gastrointestinal endoscopy.
METHODS: After obtaining approval of the research ethics committee and informed consent, 200 patients were evaluated and referred for upper gastrointestinal endoscopy. Patients were randomized to receive propofol-fentanyl or midazolam-fentanyl (n = 100/group). We assessed the level of sedation using the observer’s assessment of alertness/sedation (OAA/S) score and bispectral index (BIS). We evaluated patient and physician satisfaction, as well as the recovery time and complication rates. The statistical analysis was performed using SPSS statistical software and included the Mann-Whitney test, χ2 test, measurement of analysis of variance, and the κ statistic.
RESULTS: The times to induction of sedation, recovery, and discharge were shorter in the propofol-fentanyl group than the midazolam-fentanyl group. According to the OAA/S score, deep sedation events occurred in 25% of the propofol-fentanyl group and 11% of the midazolam-fentanyl group (P = 0.014). Additionally, deep sedation events occurred in 19% of the propofol-fentanyl group and 7% of the midazolam-fentanyl group according to the BIS scale (P = 0.039). There was good concordance between the OAA/S score and BIS for both groups (κ = 0.71 and κ = 0.63, respectively). Oxygen supplementation was required in 42% of the propofol-fentanyl group and 26% of the midazolam-fentanyl group (P = 0.025). The mean time to recovery was 28.82 and 44.13 min in the propofol-fentanyl and midazolam-fentanyl groups, respectively (P < 0.001). There were no severe complications in either group. Although patients were equally satisfied with both drug combinations, physicians were more satisfied with the propofol-fentanyl combination.
CONCLUSION: Deep sedation occurred with propofol-fentanyl and midazolam-fentanyl, but was more frequent in the former. Recovery was faster in the propofol-fentanyl group.
Endoscopy; Deep sedation; Anesthetic administration; Anesthetic dose; Adverse effects
Thirty three healthy patients (ASA 1) who required the removal of impacted third molars were included in a double-blind cross-over trial to compare the amnestic and anxiolytic efficacy of diazepam and midazolam. The anxiolytic properties of the two drugs were assessed objectively by the measurement of changes in blood pressure, pulse rate, plasma cortisol levels, and subjectively by a patient assessment using a visual analogue scale for anxiety. The amnestic properties were evaluated by patient's ability to recall two visual stimuli they were shown. The first drug given was titrated to clinical sedation and the second drug was given in an “equipotent” ratio of 1.0 midazolam to 2.86 diazepam. There was a statistically significant fall in anxiety and good levels of amnesia achieved using both drugs. No statistical differences were detected between the two drugs.
There is increasing interest in balanced propofol sedation (BPS) titrated to moderate sedation (conscious sedation) for endoscopic procedures. However, few controlled studies on BPS targeted to deep sedation for diagnostic endoscopy were found. Alfentanil, a rapid and short-acting synthetic analog of fentanyl, appears to offer clinically significant advantages over fentanyl during outpatient anesthesia.
It is reasonable to hypothesize that low dose of alfentanil used in BPS might also result in more rapid recovery as compared with fentanyl.
A prospective, randomized and double-blinded clinical trial of alfentanil, midazolam and propofol versus fentanyl, midazolam and propofol in 272 outpatients undergoing diagnostic esophagogastroduodenal endoscopy (EGD) and colonoscopy for health examination were enrolled. Randomization was achieved by using the computer-generated random sequence. Each combination regimen was titrated to deep sedation. The recovery time, patient satisfaction, safety and the efficacy and cost benefit between groups were compared.
260 participants were analyzed, 129 in alfentanil group and 131 in fentanyl group. There is no significant difference in sex, age, body weight, BMI and ASA distribution between two groups. Also, there is no significant difference in recovery time, satisfaction score from patients, propofol consumption, awake time from sedation, and sedation-related cardiopulmonary complications between two groups. Though deep sedation was targeted, all cardiopulmonary complications were minor and transient (10.8%, 28/260). No serious adverse events including the use of flumazenil, assisted ventilation, permanent injury or death, and temporary or permanent interruption of procedure were found in both groups. However, fentanyl is New Taiwan Dollar (NT$) 103 (approximate US$ 4) cheaper than alfentanil, leading to a significant difference in total cost between two groups.
This randomized, double-blinded clinical trial showed that there is no significant difference in the recovery time, satisfaction score from patients, propofol consumption, awake time from sedation, and sedation-related cardiopulmonary complications between the two most common sedation regimens for EGD and colonoscopy in our hospital. However, fentanyl is NT$103 (US$ 4) cheaper than alfentanil in each case.
Institutional Review Board of Buddhist Tzu Chi General Hospital (IRB097-18) and Chinese Clinical Trial Registry (ChiCTR-TRC-12002575)
Balanced propofol sedation; Alfentanil; Fentanyl; Deep sedation; Diagnostic endoscopy; Cost benefit
OBJECTIVE: To compare the safety and efficacy of two doses of oral midazolam, and to assess the drug induced amnesia obtained, when used for conscious sedation of children undergoing minor procedures in the accident and emergency (A&E) setting. METHODS: A two stage trial was completed: an initial prospective, double blinded, randomised trial comparing 0.2 mg/kg midazolam suspension with 0.5 mg/kg, followed by further data collection on the higher dose. Children whom staff and parents felt required sedation for accurate and humane completion of minor procedures were selected. Anxiety was measured using physiological parameters, a behavioural anxiety score, a parental visual analogue scale, and a telephone questionnaire at 2-7 days after the procedure. RESULTS: Fifty patients in total were recruited. Randomisation between two doses ceased after 20 patients since staff, despite being "blinded", perceived there to be a wide variation in response to midazolam and attributed that to the difference in doses. On breaking the code these suspicions were partly supported. Due to reluctance to continue with the lower dose all children subsequently received 0.5 mg/kg. At this higher dose oral midazolam had an onset of action of 15 minutes and was effective in 76% of children (as measured by anxiety score and/or subsequent amnesia). Amnesia was reported in 66% of children. There were no adverse side effects except paradoxical hyperagitation in three (6%); this did not require any specific treatment. General anaesthesia was avoided in at least eight children in whom the procedure would not have been attempted without midazolam. Altogether 90% of parents said they would like it to be used again should similar circumstances arise. CONCLUSIONS: At 0.5 mg/kg oral midazolam appears safe and is effective in sedating most children for minor procedures. Its use should be considered by all A&E departments dealing with children.
This study attempted to determine if sevoflurane in oxygen inhaled via a nasal hood as a sole sedative agent would provide an appropriate level of deep sedation for outpatient third molar surgery. Twenty-four patients scheduled for third molar removal were randomly assigned to receive either nasal hood inhalation sevoflurane or an intravenous deep sedation using midazolam and fentanyl followed by a propofol infusion. In addition to measuring patient, surgeon, and dentist anesthesiologist subjective satisfaction with the technique, physiological parameters, amnesia, and psychomotor recovery were also assessed. No statistically significant difference was found between the sevoflurane and midazolam-fentanyl-propofol sedative groups in physiological parameters, degree of amnesia, reported quality of sedation, or patient willingness to again undergo a similar deep sedation. A trend toward earlier recovery in the sevoflurane group was identified. Sevoflurane can be successfully employed as a deep sedative rather than a general anesthetic for extraction of third molars in healthy subjects.
Propofol induced sedation with bispectral index (BIS) monitoring has been reported to lead to higher satisfaction in patients and endoscopists during endoscopic submucosal dissection (ESD) procedures. There are no data, however, regarding the efficacy of midazolam and meperidine (M/M) induced sedation with BIS monitoring during ESD. The purpose of this study was to evaluate whether M/M induced sedation with BIS monitoring could improve satisfaction and reduce the dose of M/M required during ESD.
Between September 2009 and January 2010, 56 patients were prospectively enrolled and randomly assigned to a BIS group (n=28) and a non-BIS group (n=28). Patient and endoscopist satisfaction scores were assessed using the visual analog scale (0 to 100) following the ESD.
The mean satisfaction scores did not significantly differ between the BIS and non-BIS groups (92.3±16.3 vs 93.3±15.5, p=0.53) or endoscopists (83.1±15.4 vs 80.0±16.7, p=0.52). Although the mean meperidine dose did not differ (62.5±27.6 vs 51.0±17.3, p=0.18) between the two groups, the mean dose of midazolam in the non-BIS group was lower than in the BIS group (6.8±2.0 vs 5.4±2.1, p=0.01).
BIS monitoring during ESD did not increase the satisfaction of endoscopists or patients and did not lead to an M/M dose reduction. These results demonstrate that BIS monitoring provides no additional benefit to M/M induced sedation during ESD.
Bispectral index monitoring; Satisfaction; Midazolam; Endoscopic submucosal dissection
The purpose of the present study is to compare the injection pain of propofol with that of benzodiazepines when used for intravenous sedation. In addition, we evaluated the efficacy of coadministering a small dose of 1% lidocaine (20 mg) to reduce the pain accompanying propofol injection. Intravenous propofol, diazepam, midazolam, or flunitrazepam were administered on separate occasions to volunteers and outpatients. The degree of injection pain was evaluated by the Visual Analog Scale (VAS) ruler. The efficacy of premixed lidocaine with propofol was also compared among the patients. The venous pain of propofol was significantly more intense than that of the three other drugs (P < 0.05). The injection pain of diazepam was more intense than that of midazolam (P < 0.05). Many patients reported no pain when propofol was coadministered with lidocaine. The addition of a small dose (20 mg) of lidocaine reduced the VAS pain score to comparable levels observed for benzodiazepines. Because injection pain might affect the patients' comfort during sedation, the addition of lidocaine to the propofol injection is deemed useful for intravenous sedation.
Poor characterization of propofol pharmacokinetics and pharmacodynamics in the morbidly obese (MO) pediatric population poses dosing challenges. This study was conducted to evaluate propofol total intravenous anesthesia (TIVA) in this population.
After IRB approval, a prospective study was conducted in 20 MO children and adolescents undergoing laparoscopic surgery under clinically titrated propofol TIVA. Propofol doses/infusion rates, hemodynamic variables, times to induction and emergence, and postoperative occurrence of respiratory adverse events (RAE) were recorded, along with intraoperative blinded Bispectral Index/BIS and postoperative Ramsay sedation scores (RSS). Study subjects completed awareness questionnaires on postoperative days 1 and 3. Propofol concentrations were obtained at predetermined intra- and post-operative time points.
Study subjects ranged 9 – 18 years (age) and 97 - 99.9% (BMI for age percentiles). Average percentage variability of hemodynamic parameters from baseline was ≈ 20%. Patients had consistently below target BIS values (BIS < 40 for >90% of maintenance phase), delayed emergence (25.8 ± 22 minutes), increased somnolence (RSS ≥ 4) in the first 30 minutes of recovery from anesthesia and 30% incidence of postoperative RAE, the odds for which increased by 14% per unit increase in BMI (p ≤ 0.05). Mean propofol concentration was 6.2 mg/L during maintenance and 1.8 mg/L during emergence from anesthesia.
Our findings indicate clinical overestimation of propofol requirements and highlight the challenges of clinically titrated propofol TIVA in MO adolescents. In this setting, it may be advantageous to titrate propofol to targeted BIS levels until more accurate weight-appropriate dosing regimens are developed, to minimize relative overdosing and its consequences.
Morbidly obese; Bariatric; Propofol; Total intravenous anesthesia; Bispectral index; Anesthetic depth; Pediatric; Adolescents
AIM: To determine whether bispectral index (BIS) monitoring is useful for propofol administration for deep sedation during endoscopic retrograde cholangiopancreatography (ERCP).
METHODS: Fifty-nine consecutive patients with a variety of reasons for ERCP who underwent the procedure at least twice between 1 July 2010 and 30 November 2010. This was a randomized cross-over study, in which each patient underwent ERCP twice, once with BIS monitoring and once with control monitoring. Whether BIS monitoring was done during the first or second ERCP procedure was random. Patients were intermittently administered a mixed regimen including midazolam, pethidine, and propofol by trained nurses. The nurse used a routine practice to monitor sedation using the Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) scale or the BIS monitoring. The total amount of midazolam and propofol used and serious side effects were compared between the BIS and control groups.
RESULTS: The mean total propofol dose administered was 53.1 ± 32.2 mg in the BIS group and 54.9 ± 30.8 mg in the control group (P = 0.673). The individual propofol dose received per minute during the ERCP procedure was 2.90 ± 1.83 mg/min in the BIS group and 3.44 ± 2.04 mg in the control group (P = 0.103). The median value of the MOAA/S score during the maintenance phase of sedation was comparable for the two groups. The mean BIS values throughout the procedure (from insertion to removal of the endoscope) were 76.5 ± 8.7 for all 59 patients in using the BIS monitor. No significant differences in the frequency of < 80% oxygen saturation, hypotension (< 80 mmHg), or bradycardia (< 50 beats/min) were observed between the two study groups. Four cases of poor cooperation occurred, in which the procedure should be stopped to add the propofol dose. After adding the propofol, the procedure could be conducted successfully (one case in the BIS group, three cases in the control group). The endoscopist rated patient sedation as excellent for all patients in both groups. All patients in both groups rated their level of satisfaction as high (no discomfort). During the post-procedural follow-up in the recovery area, no cases of clinically significant hypoxic episodes were recorded in either group. No other postoperative side effects related to sedation were observed in either group.
CONCLUSION: BIS monitoring trend to slighlty reduce the mean propofol dose. Nurse-administered propofol sedation under the supervision of a gastroenterologist may be considered an alternative under anesthesiologist.
Conscious sedation; Bispectral index monitors; Pancreatic neoplasm; Endoscopic retrograde cholangiopancreatography
In most extracorporeal membrane oxygenation (ECMO) centers patients are heavily sedated to prevent accidental decannulation and bleeding complications. In ventilated adults not on ECMO, daily sedation interruption protocols improve short- and long-term outcome. This study aims to evaluate safety and feasibility of sedation interruption following cannulation in neonates on ECMO.
Prospective observational study in 20 neonates (0.17–5.8 days of age) admitted for ECMO treatment. Midazolam (n = 20) and morphine (n = 18) infusions were discontinued within 30 min after cannulation. Pain and sedation were regularly assessed using COMFORT-B and visual analog scale (VAS) scores. Midazolam and/or morphine were restarted and titrated according to protocolized treatment algorithms.
Median (interquartile range, IQR) time without any sedatives was 10.3 h (5.0–24.1 h). Median interruption duration for midazolam was 16.5 h (6.6–29.6 h), and for morphine was 11.2 h (6.7–39.4 h). During this period no accidental extubations, decannulations or bleeding complications occurred.
This is the first study to show that interruption of sedatives and analgesics following cannulation in neonates on ECMO is safe and feasible. Interruption times are 2–3 times longer than reported for adult ICU patients not on ECMO. Further trials are needed to substantiate these findings and evaluate short- and long-term outcomes.
Neonate; Extracorporeal membrane oxygenation; Sedation; Daily interruption
The aim of this study was to define the optimal target concentration of remifentanil which effectively achieves conscious sedation without significant vital sign changes and side effects during spinal anesthesia.
Sixty patients underwent spinal anesthesia with 0.5% hyperbaric bupivacaine (8-16 mg), and were infused with a target controlled infusion (TCI) of remifentanil at 1.0 ng/ml (group R10, n = 15), 2.0 ng/ml (group R20, n = 15), 3.0 ng/ml (group R30, n = 15), and 3.5 ng/ml (group R35, n = 15). Observer's assessment of alertness/sedation (OAA/S) scale, the bispectral index (BIS), anxiety levels and infusion rate of remifentanil were monitored during the operation.
OAA/S scale was significantly lower in groups R30 (3.96) and R35 (3.34) than groups R10 (4.31) and R20 (4.26). Incidence of intraoperative respiratory depression events, post operative nausea and vomiting were significantly higher in group R35 than the other groups. There were no significant differences in BIS, anxiety level and incidences of recall of the operative procedure among the groups.
We conclude that the TCI of remifentanil at 3.0 ng/ml produces an effective sedation and anti-anxiety effects without significant side effects during spinal anesthesia.
Conscious sedation; Remifentanil; Spinal anesthesia; Target controlled Infusion
This study aimed to compare continuous intravenous infusion combinations of propofol-remifentanil and propofol-ketamine for deep sedation for surgical extraction of all 4 third molars. In a prospective, randomized, double-blinded controlled study, participants received 1 of 2 sedative combinations for deep sedation for the surgery. Both groups initially received midazolam 0.03 mg/kg for baseline sedation. The control group then received a combination of propofol-remifentanil in a ratio of 10 mg propofol to 5 μg of remifentanil per milliliter, and the experimental group received a combination of propofol-ketamine in a ratio of 10 mg of propofol to 2.5 mg of ketamine per milliliter; both were given at an initial propofol infusion rate of 100 μg/kg/min. Each group received an induction loading bolus of 500 μg/kg of the assigned propofol combination along with the appropriate continuous infusion combination . Measured outcomes included emergence and recovery times, various sedation parameters, hemodynamic and respiratory stability, patient and surgeon satisfaction, postoperative course, and associated drug costs. Thirty-seven participants were enrolled in the study. Both groups demonstrated similar sedation parameters and hemodynamic and respiratory stability; however, the ketamine group had prolonged emergence (13.6 ± 6.6 versus 7.1 ± 3.7 minutes, P = .0009) and recovery (42.9 ± 18.7 versus 24.7 ± 7.6 minutes, P = .0004) times. The prolonged recovery profile of continuously infused propofol-ketamine may limit its effectiveness as an alternative to propofol-remifentanil for deep sedation for third molar extraction and perhaps other short oral surgical procedures, especially in the ambulatory dental setting.
Propofol; Ketamine; Remifentanil; Deep sedation; TIVA
The use of monitored anesthesia care (MAC) as the technique of choice for a variety of invasive or noninvasive procedures is increasing. The purpose of this study to compare the outcomes of two different methods, spinal anesthesia and ilioinguinal-hypogastric nerve block (IHNB) with target concentrated infusion of remifentanil for inguinal herniorrhaphy.
Fifty patients were assigned to spinal anesthesia (Group S) or IHNB with MAC group (Group M). In Group M, IHNB was performed and the effect site concentration of remifentanil, starting from 2 ng/ml, was titrated according to the respiratory rate or discomfort, either by increasing or decreasing the dose by 0.3 ng/ml. The groups were compared to assess hemodynamic values, oxygen saturation, bispectral index (BIS), observer assessment alertness/sedation scale (OAA/S), visual analogue scale (VAS) for pain score and patients' and surgeon's satisfaction.
BIS and OAA/S were not significantly different between the two groups. Hemodynamic variables were stable in Group M. Thirteen patients in the same group showed decreased respiratory rate without desaturation, and recovered immediately by encouraging taking deep breaths without the use of assist ventilation. Although VAS in the ward was not significantly different between the two groups, interestingly, patients' and surgeon's satisfaction scores (P = 0.0004, P = 0.004) were higher in Group M. The number of the patients who suffered from urinary retention was higher in Group S (P = 0.0021).
IHNB under MAC with remifentanil is a useful method for inguinal herniorrhaphy reflecting hemodynamic stability, fewer side effects and higher satisfaction. This approach can be applied for outpatient surgeries and patients who are unfit for spinal anesthesia or general anesthesia.
Inguinal herniorrhaphy; Monitored anesthesia care; Remifentanil; Spinal anesthesia
We made a survey among Finnish anesthesiologists concerning the current perioperative anesthetic practice of hip fracture patients for further development in patient care.
All members of the Finnish Society of Anesthesiologists with a known e-mail address (786) were invited to participate in an internet-based survey.
The overall response rate was 55% (423 responses); 298 respondents participated in the care of hip fracture patients. Preoperative analgesia was mostly managed with oxycodone and paracetamol; every fifth respondent applied an epidural infusion. Most respondents (98%) employed a spinal block with or without an epidural catheter for intraoperative anesthesia. Midazolam, propofol and/or fentanyl were used for additional sedation. General anesthesia was used rarely. Postoperatively, paracetamol and non-steroidal anti-inflammatory drugs and occasionally peroral oxycodone, were prescribed in addition to epidural analgesia.
The survey suggests that the impact of more individualised analgesia regimens, both preoperatively and postoperatively, should be investigated in further studies.
Hip fracture; Perioperative management; Anesthetic practice
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 (≥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, ≥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.
Trial Registration: clinicaltrials.gov Identifier: NCT00590707
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.
For patients in the intensive care unit (ICU) or under monitored anesthetic care (MAC), the precise monitoring of sedation depth facilitates the optimization of dosage and prevents adverse complications from underor over-sedation. For this purpose, conventional subjective sedation scales, such as the Observer's Assessment of Alertness/Sedation (OAA/S) or the Ramsay scale, have been widely utilized. Current procedures frequently disturb the patient's comfort and compromise the already well-established sedation. Therefore, reliable objective sedation scales that do not cause disturbances would be beneficial. We aimed to determine whether spectral entropy can be used as a sedation monitor as well as determine its ability to discriminate all levels of propofol-induced sedation during gradual increments of propofol dosage.
In 25 healthy volunteers undergoing general anesthesia, the values of response entropy (RE) and state entropy (SE) corresponding to each OAA/S (5 to 1) were determined. The scores were then analyzed during each 0.5 mcg/ml- incremental increase of a propofol dose.
We observed a reduction of both RE and SE values that correlated with the OAA/S (correlation coefficient of 0.819 in RE-OAA/S and 0.753 in SE-OAA/S). The RE and SE values corresponding to awake (OAA/S score 5), light sedation (OAA/S 3-4) and deep sedation (OAA/S 1-2) displayed differences (P < 0.05).
The results indicate that spectral entropy can be utilized as a reliable objective monitor to determine the depth of propofol-induced sedation.
Entropy; Propofol; Sedation
Objective assessment of sedation depth is a valuable target. Spectral entropy is an anesthetic depth monitor based on the analysis of the electroencephalogram signal.
To evaluate the performance of spectral entropy as an objective measure of sedation state in midazolam-premedicated patients and to correlate it with a clinically assessed sedation score.
Settings and Design:
This prospective double-blind placebo-controlled study was performed in King Fahd Hospital of the university.
Eighty adult ASA I–II patients were randomly assigned into 4 groups. Patients were premedicated using 0.02, 0.04, or 0.06 mg/kg midazolam or saline intramuscularly. The effect of these doses on the Observer's Assessment of Alertness and Sedation (OAA/S) scale, hemodynamic variables, response entropy (RE), and state entropy (SE), was evaluated at 10, 20, and 30 min after premedication.
Spearman Rank-order correlation analysis to examine the relation between OAA/S and entropy. The ability of spectral entropy to predict the depth of sedation was evaluated using Smith prediction probability.
Midazolam doses ≥0.04 mg/kg produced significant decreases in RE, SE, and OAA/S scores. There was a strong correlation between midazolam dose and OAA/S scale, RE, and SE since Spearman Rank R values were 0.792, 0.822, and 0.745, respectively (P<0.001). In addition, RE and SE were strong predictors of OAA/S level during midazolam sedation with no significant difference in prediction between the 2 entropy components.
Spectral entropy is a reliable measure for the sedative premedication. It may be used to objectively assess the adequacy of midazolam premedication and to determine the dose requirement.
Monitoring; depth of anaesthesia; observer's assessment of alertness and sedation; premedication; midazolam; sedation
This study was conducted to compare the efficacy and effects of dexmedetomidine and midazolam in preoperative sedation.
Materials and Methods:
A total of 125 patients in American Society of Anaesthesiologists (ASA) I-II were divided into three groups: Group I (n = 40) for controls, Group II (n = 40) for Dexmedetomidine (1 μg/kg), and group III was the midazolam group (n = 45). Group III was further divided into three subgroups according to the doses of midazolam: Group IIIA (n = 15) received 0.02 mg/kg, group IIIB (n = 15) received 0.04 mg/kg, and group IIIC (n = 15) received 0.06 mg/kg of midazolam. Drugs were infused over a 10-minute period with appropriate monitoring. Ramsay and visual analog scores, for sedation and anxiety, respectively, and mean arterial pressure, heart rate, and SpO2 measurement, including respiratory rates were recorded, every 5 minutes for 30 minutes following infusion.
There was marked sedation and a decrease in anxiety in groups II and IIIC (P < 0.01). Mean arterial pressure (MAP) and heart rate (HR) decreased significantly in group II (P < 0.01 and P < 0.05, respectively), but there was no associated hypotension (MAP <60 mm Hg) or bradycardia (HR <50 bpm) (P < 0.05). Respiratory rates and SpO2 values decreased in groups II, IIIA, IIIB, and IIIC. The differences in respiratory rates were not significant (P > 0.05); however, decrease in SpO2 was significant in group IIIC (P < 0.01).
Dexmedetomidine was as effective as higher doses of midazolam in sedation. The hemodynamic and respiratory effects were minimal. Although dexmedetomidine caused significant decrease in the blood pressure and heart rate, it probably just normalized increased levels caused by preoperative stress.
Dexmedetomidine; general anesthesia; midazolam; premedication; sedation
Dexmedetomidine has a sedative analgesic property without respiratory depression. This study evaluated the efficacy of dexmedetomidine as an appropriate sedative drug for monitored anesthesia care (MAC) in outpatients undergoing cataract surgery on both eyes compared with combination of propofol and alfentanil.
Thirty-one eligible patients were randomly divided into two groups on the first operation day. Dexmedetomidine was administered in group D at 0.6 µg/kg/h, and propofol and alfentanil was infused concomitantly in group P at a rate of 2 mg/kg/h and 20 µg/kg/h, respectively. Sedation was titrated at Ramsay sedation score 3. Iowa satisfaction with anesthesia scale (ISAS) of the patients was evaluated postoperatively. Systolic blood pressure (SBP), heart rate (HR), respiration rate (RR), and peripheral oxygen saturation (SpO2) were recorded throughout the surgery. For the second operation, the group assignments were exchanged.
Postoperative ISAS was 50.3 (6.2) in group D and 42.7 (8.7) in group P, which was statistically significant (P < 0.001). SBP was significantly lower in group D compared with group P from the beginning of the operation. HR, RR, and SpO2 were comparable between the two groups. There were 8 cases (25.8%) of hypertension in group P, and 1 case (3.2%) in group D (P < 0.05). In contrast, 1 case (3.2%) of hypotension and 1 case (3.2%) of bradycardia occurred in group D.
Compared with the combined use of propofol and alfentanil, dexmedetomidine could be used appropriately for MAC in cataract surgery with better satisfaction from the patients and a more stable cardiovascular state.
Cataract; Dexmedetomidine; Monitored anesthesia care; Propofol
The purpose of this study was to evaluate sedation practice in UK intensive care units (ICUs), particularly the implementation of daily sedation holding, written sedation guidelines, sedation scoring tools and choice of agents.
A national postal survey was conducted in all UK ICUs.
A total of 192 responses out of 302 addressed units were received (63.5%). Of the responding ICUs, 88% used a sedation scoring tool, most frequently the Ramsey Sedation Scale score (66.4%). The majority of units have a written sedation guideline (80%), and 78% state that daily sedation holding is practiced. A wide variety of sedating agents is used, with the choice of agent largely determined by the duration of action rather than cost. The most frequently used agents were propofol and alfentanil for short-term sedation; propofol, midazolam and morphine for longer sedation; and propofol for weaning purposes.
Most UK ICUs use a sedation guideline and sedation scoring tool. The concept of sedation holding has been implemented in the majority of units, and most ICUs have a written sedation guideline.
Regional anaesthesia has become an important anaesthetic technique. Effective sedation is an essential for regional techniques too. This study compares midazolam and propofol in terms of onset & recovery from sedation, dosage and side effects of both the drugs using Bispectral Index monitoring. Ninety eight patients were randomly divided into two groups,one group recieved midazolam infusion while the other recieved propofol infusion until BIS reached 75. We observed Time to reach desired sedation, HR, MABP, time for recovery, dose to reach sedation and for maintenance of sedation and side effects if any. The time to reach required sedation was 11 min in Midazolam group(Group I) while it was 6 min in Propofol group(Group II) (p=0.0). Fall in MABP was greater with propofol. Recovery in with midazolam was slower than with propofol (18.6 ± 6.5 vs 10.10±3.65 min) (p=0.00). We concluded that both midazolam and propofol are effective sedatives, but onset and offset was quicker with propofol, while midazolam was more cardiostable.
Propofol; Midazolam; Sedation; BIS
The purpose of this study was to evaluate the hemodynamic, respiratory effects, the recovery profile, surgeons, and patients satisfaction with dexmedetomidine sedation compared with those of propofol sedation in patients undergoing vitreoretinal surgery under sub-Tenon’s anesthesia.
Sixty patients were enrolled in this prospective, single-blind, randomized study. The patients were divided into two groups to receive either dexmedetomidine (group D) or propofol (group P). Sedation level was titrated to a Ramsay sedation scale (RSS) of 3. Hemodynamic and respiratory effects, postoperative recovery time, analgesic effects, surgeons and patients satisfaction were assessed.
Both groups provided a similar significant reduction in heart rate and mean arterial pressure compared with baseline values. The respiratory rate values of the dexmedetomidine group were significantly higher than those in the propofol group. The oxygen saturation values of the dexmedetomidine group were significantly higher than those of the propofol group. The expired CO2 was similar in both groups. Postoperatively, the time to achieve an Aldrete score of 10 was similar in both groups. Dexmedetomidine patients have significantly lower visual analog scale for pain than propofol patients. The surgeon satisfaction with patients’ sedation was similar for both groups. The patients’ satisfaction was higher in the dexmedetomidine group.
Dexmedetomidine at similar sedation levels with propofol was associated with equivalent hemodynamic effects, maintaining an adequate respiratory function, similar time of discharge from PACU, better analgesic properties, similar surgeon’s satisfaction, and higher patient’s satisfaction. Thus, dexmedetomidine may prove to be a valuable adjuvant for sedation in patients undergoing vitreoretinal surgery under sub-Tenon’s anesthesia.
Dexmedetomidine; propofol; sedation; vitreoretinal surgery
Analgesia and sedation are usually required for the comfort of the patient and surgeon during tympanoplasty surgery done under local anesthesia. In this study, satisfaction scores and effectiveness of sedation and analgesia with dexmedetomidine were compared with a combination of midazolam-fentanyl.
Materials and Methods:
Ninety patients undergoing tympanoplasty under local anesthesia randomly received either IV dexmedetomidine 1 μg kg-1 over 10 min followed by 0.2 μg kg-1h-1 infusion (Group D) or IV midazolam 0.06 mg kg-1 plus IV fentanyl 1 μg kg-1 over 10 min (Group MF) followed by normal saline infusion at 0.2 ml kg-1h-1. Sedation was titrated to Ramsay sedation score (RSS) of three. Vital parameters, rescue analgesics (fentanyl 1 μg kg-1) and sedatives (midazolam 0.01 mg kg-1), patient and surgeon satisfaction scores were recorded.
Patient and surgeon satisfaction score was better in Group D than Group MF (median interquartile range (IQR) 9 (8-10) vs. 8 (6.5-9.5) and 9 (8.5-9.5) vs. 8 (6.75-9.25), P = 0.0001 for both). Intraoperative heart rate and mean arterial pressure in Group D were lower than the baseline values and the corresponding values in Group MF (P < 0.05). Percentage of patients requiring rescue fentanyl was higher in Group MF than Group D (40% vs. 11.1%, P = 0.01). One patient in Group D while four in Group MF (8.8%) required rescue sedation with midazolam (P > 0.17). Seven patients in Group D had dry mouth vs. none in Group MF (P = 0.006). One patient in Group D had bradycardia with hypotension which was effectively treated.
Dexmedetomidine is comparable to midazolam-fentanyl for sedation and analgesia in tympanoplasty with better surgeon and patient satisfaction. Hemodynamics need to be closely monitored.
Dexmedetomidine; sedation; midazolam fentanyl sedation; monitored anesthesia care; satisfaction scores; surgery; otological