Bispectral electroencephalographic analysis of patients undergoing procedural sedation in the emergency department
TL;DR: Whether there is a correlation between the level of sedation achieved during procedural sedation (PS) in the emergency department as determined by bispectral electroencephalographic (EEG) analysis (BIS) and the rate of respiratory depression (RD), the patient's perception of pain, recall of the procedure, and satisfaction is investigated.
Abstract: Objective: To determine whether there is a correlation between the level of sedation achieved during procedural sedation (PS) in the emergency department as determined by bispectral electroencephalographic (EEG) analysis (BIS) and the rate of respiratory depression (RD), the patient's perception of pain, recall of the procedure, and satisfaction. Methods: This was a prospective observational study conducted in an urban county hospital of adult patients undergoing PS using propofol, methohexital, etomidate, and the combination of fentanyl and midazolam. Consenting patients were monitored by vital signs, pulse oximetry, nasal-sample end-tidal carbon dioxide (ETCO 2 ), and BIS monitors during PS. Respiratory depression (RD) was defined as an oxygen saturation 10 mm Hg, or an absent ETCO 2 waveform at any time during the procedure. After the procedure, patients were asked to complete three 100-mm visual analog scales (VASs) concerning their perception of pain, recall of the procedure, and satisfaction with the procedure. Patients were divided into four groups based on the lowest BIS score recorded during the procedure, group 1, >85; group 2, 70-85; group 3, 60-69; group 4, <60. Rates of RD and VAS outcomes were compared between groups using chi-square statistics. Results: One hundred eight patients were enrolled in the study. No serious adverse events were noted. RD was seen in three of 14 (21.4%) of the patients in group 1, seven of 34 (20.6%) in group 2, 16 of 26 (61.5%) in group 3, and 18 of 34 (52.9%) in group 4. The rate of RD in patients in group 2 was not significantly different from that in group 1 (p = 0.46). The rate of RD in group 2 was significantly lower than that in groups 3 (p = 0.0003) and 4 (p = 0.006). For the VAS data, when group 1 was compared with the combined groups 2, 3, and 4, it had significantly higher rates of pain (p = 0.003) and recall (p = 0.001), and a dissatisfaction rate (p = 0.085) that approached significance. When groups 2, 3, and 4 were compared with chi-square test, there was not a significant difference in pain (p = 0.151), recall (p = 0.27), or satisfaction (p = 0.25). Conclusions: Patients with a lowest recorded BIS score between 70 and 85 had the same VAS outcomes as more deeply sedated patients and the same rate of RD as less deeply sedated patients. This range of scores represented the optimally sedated patients in this study.
Citations
More filters
TL;DR: This clinical policy from the American College of Emergency Physicians is the revision of a 2005 clinical policy evaluating critical questions related to procedural sedation in the emergency department.
455Â citations
Cites result from "Bispectral electroencephalographic ..."
...2 : February 2005 induced procedural sedation was reported to have the lowest rate of respiratory depression when compared with methohexital, fentanyl/midazolam, and etomidate.(21) There were no significant complications....
[...]
TL;DR: BIS technology is moving out of the operating room and into diverse environments where conscious and deep sedation are provided, and anesthesiologists need to be actively involved in promoting patient safety and helping transition this technology into broader use.
283Â citations
TL;DR: When ketamine is used for procedural sedation in adults, emergence phenomena occur in 10% to 20% of patients, and reports of significant cardiorespiratory adverse events are rare, despite ketamine's frequent use in austere, poorly monitored settings.
Abstract: Study Objectives: Ketamine is widely used as a procedural sedation agent in pediatrics, where its safety and efficacy are supported by numerous studies. Emergency physicians use ketamine infrequently in adults, as it is believed to have a more significant side effect profile in this population. However, adult data on ketamine use in the emergency medicine literature are sparse. Our objective was to determine ketamine's adverse effect profile in adults when used for procedural sedation. Methods: We performed a literature review based on adverse effect research methodology recommendations. PubMed, EMBASE, TOXNET, and a variety of specialized databases were queried without regard to publication date or language. Experts were contacted to locate additional data. Inclusion criteria included adult study; ketamine used to facilitate the performance of painful procedures; dose of at least 1 mg/kg intravenous or at least 2 mg/kg intramuscular; original data and adverse events reported; spontaneously breathing patient, and no continuous cotherapies. Studies that met inclusion criteria were abstracted onto structured forms and their results qualitatively summarized. Results: Of the 5512 unique citations that were evaluated, 87 met criteria for inclusion. Most studies were performed in the 1970s and published in the anesthesia literature. Contexts, end points, and methodological quality varied widely across studies. Ketamine reliably produces conditions that facilitate the performance of painful procedures. Pharyngeal reflexes are generally preserved and cardiovascular tone stimulated, including a rise in blood pressure and myocardial oxygen demand. Laryngospasm and airway obstruction are reported, and though ketamine is a respiratory stimulant, a brief period of apnea around the time of injection is common. Reports of significant cardiorespiratory adverse events are rare, despite ketamine's frequent use in austere, poorly monitored settings. Dysphoric emergence phenomena occur in 10% to 20% of cases; sedating medications are effective in preventing and managing these reactions. Conclusion: When ketamine is used for procedural sedation in adults, emergence phenomena occur in 10% to 20% of patients. Although providers must be prepared to recognize and manage airway obstruction, cardiorespiratory adverse events are rare and typically do not affect outcomes.
258Â citations
Cites background from "Bispectral electroencephalographic ..."
...Propofol features favorable pharmacokinetics but no analgesia; painful procedures therefore require aggressive dosing to bring about comparatively deeper sedation, which exposes the patient to its potent vasodilatory and respiratory depressant properties that may become clinically significant in longer procedures [151-155]....
[...]
...[153] Miner JR, Biros MH, Heegaard W, Plummer D....
[...]
TL;DR: An evidence-based clinical practice advisory for the administration of propofol for emergency department procedural sedation and critically discusses indications, contraindications, personnel and monitoring requirements, dosing, coadministered medications, and patient recovery from prop ofol is presented.
181Â citations
Cites background from "Bispectral electroencephalographic ..."
...Unlike midazolam and fentanyl, which are classically titrated together, propofol should be administered as a sole agent after complete or near-complete analgesia has been achieved with an opiate.(8-10,12,56)...
[...]
...Pain With Injection Injection site pain with propofol is uncommon in existing ED reports (2% to 20%).(1,4-11,13,24,56) As a consequence, no strategies to mitigate such discomfort have been reported in our setting....
[...]
...Both mechanical monitoring and direct visualization are required to detect all changes in respiratory effort or the patient’s level of consciousness.(9,11,58) Continuous pulse oximetry is a routine monitoring modality for all ED sedation (including propofol) and will effectively detect hypoxemia associated with hypoventilation, apnea, or airway obstruction....
[...]
...com).(1,2,4-17) A clinical practice guideline addressing the use of ketamine for ED dissociative sedation has been published....
[...]
...Indications The literature supports the safety and efficacy of propofol for a variety of ED procedures requiring deep sedation, including fracture and dislocation reduction, incision and drainage of abscesses, and cardioversion.(1,2,4-17,24-29) There is no ED experience using propofol for minimal sedation and limited experience for moderate sedation in the ED....
[...]
TL;DR: In adults receiving ED propofol sedation, the addition of capnography to standard monitoring reduced hypoxia and provided advance warning for all hypoxic events.
180Â citations
Cites background from "Bispectral electroencephalographic ..."
...CO2 (ETCO2) waveform has been suggested to identify patients at risk of developing significant respiratory depression.(7)...
[...]
References
More filters
TL;DR: The bispectral index, a value derived from the electroencephalograph (EEG), has been proposed as a measure of anesthetic effect and its utility is important to establish its utility.
Abstract: Background:The bispectral index (BIS), a value derived from the electroencephalograph (EEG), has been proposed as a measure of anesthetic effect. To establish its utility for this purpose, it is important to determine the relation among BIS, measured drug concentration, and increasing levels of seda
1,222Â citations
TL;DR: Combining midazolam with fentanyl or other opioids produces a potent drug interaction that places patients at a high risk for hypoxemia and apnea, andequate precautions are recommended when benzodiazepines are administered in combination with opioids.
Abstract: More than 80 deaths have occurred after the use of midazolam (Versed), often in combination with opioids, to sedate patients undergoing various medical and surgical procedures. We investigated the respiratory effects of midazolam (0.05 mg.kg-1) and fentanyl (2.0 micrograms.kg-1) in volunteers. The incidence of hypoxemia (oxyhemoglobin saturation less than 90%) and apnea (no spontaneous respiratory effort for 15 s) and the ventilatory response to carbon dioxide were evaluated. Midazolam alone produced no significant respiratory effects. Fentanyl alone produced hypoxemia in half of the subjects and significant depression of the ventilatory response to CO2, but did not produce apnea. Midazolam and fentanyl in combination significantly increased the incidence of hypoxemia (11 of 12 subjects) and apnea (6 of 12 subjects), but did not depress the ventilatory response to CO2 more than did fentanyl alone. Adverse reactions linked to midazolam and reported to the Department of Health and Human Services highlight apnea- and hypoxia-related problems as among the most frequent adverse reactions. Seventy-eight per cent of the deaths associated with midazolam were respiratory in nature, and in 57% an opioid had also been administered. All but three of the deaths associated with the use of midazolam occurred in patients unattended by anesthesia personnel. We conclude that combining midazolam with fentanyl or other opioids produces a potent drug interaction that places patients at a high risk for hypoxemia and apnea. Adequate precautions, including monitoring of patient oxygenation with pulse oximetry, the administration of supplemental oxygen, and the availability of persons skilled in airway management are recommended when benzodiazepines are administered in combination with opioids.
572Â citations
TL;DR: The BIS index appears to be a useful variable for assessing the depth of propofol-induced sedation and amnesia during regional anesthesia as increasing depth of sedation was associated with a significant decrease in intraoperative picture recall.
Abstract: The bispectral (BIS) index and 95% spectral edge frequency (SEF) of the electroencephalograph (EEG) have been used to study the anesthetic and sedative effects of intravenously (i.v.) administered drugs. This prospective study was designed to evaluate the effectiveness of the BIS index and 95% SEF for assessing the level of propofol-induced sedation and amnesia during regional anesthesia. Ten consenting adult patients undergoing surgery with regional anesthesia were administered propofol in increments of 10-20 mg i.v., every 5-10 min until they became unresponsive to tactile stimulation (i.e., mild prodding or shaking). The BIS index and 95% SEF were continuously recorded from a bifrontal montage (Fp1-Cz and Fp2-Cz) using the Aspect B500 monitor. The depth of sedation was assessed clinically at 5- to 10-min intervals using the observer's assessment of alertness/sedation (OAA/S) scale, with 1 = no response to tactile stimulation to 5 = wide awake. Each patient was shown a picture of an animal (cat) prior to administration of an initial dose of propofol, 40 mg i.v.. Subsequently, patients were administered intermittent bolus doses of propofol, 10-20 mg i.v., and shown different pictures upon achieving OAA/S scores of 4, 3, and 2 during the onset of and recovery from propofol-induced sedation. Picture recall was tested upon arrival of the patient in the postanesthesia care unit (PACU). Of the two EEG variables studied, the BIS index exhibited a better correlation with the OAA/S scores during both the onset (Spearman's rho = 0.744) and recovery (Spearman's rho = 0.705) phases of propofol-induced sedation. With the increasing depth of sedation, there was a progressive decrease in the BIS index (OAA/S score of 5, BIS = 94.5 +/- 2.9; 4, 93.3 +/- 3.3; 3, 89 +/- 6.1; 2, 80.1 +/- 8.7; 1, 75.6 +/- 7.5; mean +/- SD). Conversely, there was a progressive increase in the BIS value during recovery from propofol sedation (OAA/S score of 1, BIS = 75.6 +/- 7.5; 2, 82.4 +/- 10.5; 3, 84.9 +/- 5.9; 4, 93.8 +/- 0.8). Although the changes in the 95% SEF values were less consistent during the onset phase, this EEG variable increased from 16.4 +/- 5.0 to 19.3 +/- 5.6 as the OAA/S score increased from 1 to 4 during the recovery phase. Patient recall of the intraoperative pictures decreased with increasing depth of sedation and decreasing BIS values (OAA/S:% BIS:% recall = 5:94.5 +/- 2.9:100%; 4:93.4 +/- 3:63%; 3:87.3 +/- 6.1:40%; 2:80.8 +/- 8.3:0%; 1:75.6 +/- 7.5:0%). The BIS index appears to be a useful variable for assessing the depth of propofol-induced sedation. Increasing depth of sedation was associated with a significant decrease in intraoperative picture recall.
479Â citations
TL;DR: Bispectral index accurately predicts response to verbal commands during sedation and hypnosis with propofol or prop ofol plus nitrous oxide and provided additional predictive power when combined with treatment history.
Abstract: BackgroundThe bispectral index (BIS) measures changes in the interfrequency coupling of the electroencephalogram (EEG). The purposes of this study were (1) to determine whether BIS correlates with responses to command during sedation and hypnosis induced by propofol or propofol and nitrous oxide, an
325Â citations
TL;DR: The data suggest that improved anesthetic titration with BIS provides sufficient clinical and economic benefits to justify its routine use and describes how BIS monitoring can be used to improve anesthetic outcomes.
320Â citations