Agitation Sedation Score Research Articles

Application of quantitative EEG in sedation depth monitoring after traumatic brain injure operation

Objective To observe the dynamic changes of the power parameters of each frequency band of electroencephalography during the postoperative sedation process of traumatic brain injuries (TBI) to evaluate the values of EEG power in assessing sedation depth. Methods A retrospective case series study was conducted on the clinical postoperative data of 42 patients with TBI from February 2017 to January 2018. There were 22 males and 20 females, aged (39.8±5.3)years (range, 25-66 years). Before the sedation, the Glasgow Coma Scale (GCS) was (9.2±2.3)points, ranging from 8 to 12 points. Before the administration of dexmedetomidine (Dex) and 10, 30, 60, 90 minutes after the medication, the body temperature, respiration, heart rate, oxygen saturation (SpO2), and mean arterial pressure (MAP) were recorded and evaluated by Ricker sedation agitation score (SAS). At the same time, the EEG power value changes of four frequency bands (α, β, θ, and δ) were recorded constantly. Correlation analysis was performed between the changing power values and corresponding SAS. Results (1) During sedation, the body temperature, respiration, heart rate, SpO2 and MAP did not show significant fluctuation along with the decrease of SAS (P>0.01). (2) Before and after Dex sedation, the electroencephalography power value of the delta band was negatively correlated with SAS, with the correlation coefficient absolute value between 0.85 and 0.88 (P 0.01). Conclusions The electroencephalography power values of the δ band of each brain region are negatively correlated with SAS and can objectively reflect the dynamic changes of the sedation depth. The absolute values of correlation coefficient between bilateral frontal δ band power and SAS can serve as a better guide for clinical sedation. Key words: Conscious sedation; Electroencephalography; Brain injuries; Dexmedetomidine

Evaluation of the thermal antinociceptive effects and pharmacokinetics of hydromorphone hydrochloride after intramuscular administration to cockatiels (Nymphicus hollandicus).

OBJECTIVE To evaluate the thermal antinociceptive effects and pharmacokinetics of hydromorphone hydrochloride after IM administration to cockatiels (Nymphicus hollandicus). ANIMALS 16 healthy adult cockatiels. PROCEDURES During the first of 2 study phases, each cockatiel received each of 4 treatments (hydromorphone at doses of 0.1, 0.3, and 0.6 mg/kg and saline [0.9% NaCl] solution [0.33 mL/kg; control], IM), with a 14-day interval between treatments. For each bird, foot withdrawal to a thermal stimulus was determined following assignment of an agitation-sedation score at predetermined times before and for 6 hours after each treatment. During the second phase, a subset of 12 birds received hydromorphone (0.6 mg/kg, IM), and blood samples were collected at predetermined times for 9 hours after drug administration. Plasma hydromorphone concentration was determined by liquid chromatography-mass spectrometry. Noncompartmental analysis of sparse data was used to calculate pharmacokinetic parameters. RESULTS Thermal withdrawal response did not differ among the 4 treatment groups at any time. Agitation-sedation scores following administration of the 0.3-and 0.6-mg/kg doses of hydromorphone differed significantly from those treated with saline solution and suggested the drug had a sedative effect. Plasma hydromorphone concentrations were > 1 ng/mL for 3 to 6 hours after drug administration in all birds. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that IM administration of hydromorphone at the evaluated doses did not increase the thermal withdrawal threshold of cockatiels despite plasma drug concentrations considered therapeutic for other species. Further research is necessary to evaluate the analgesic effects of hydromorphone in cockatiels.

Brain Monitoring of Sedation in the Intensive Care Unit Using a Recurrent Neural Network.

Over and under-sedation are common in critically ill patients admitted to the Intensive Care Unit. Clinical assessments provide limited time resolution and are based on behavior rather than the brain itself. Existing brain monitors have been developed primarily for non-ICU settings. Here, we use a clinical dataset from 154 ICU patients in whom the Richmond Agitation-Sedation Score is assessed about every 2 hours. We develop a recurrent neural network (RNN) model to discriminate between deep vs. no sedation, trained end-to-end from raw EEG spectrograms without any feature extraction. We obtain an average area under the ROC of 0.8 on 10-fold cross validation across patients. Our RNN is able to provide reliable estimates of sedation levels consistently better compared to a feed-forward model with simple smoothing. Decomposing the prediction error in terms of sedatives reveals that patient-specific calibration for sedatives is expected to further improve sedation monitoring.

Evaluation of the Thermal Antinociceptive Effects of a Sustained-Release Buprenorphine Formulation After Intramuscular Administration to American kestrels ( Falco sparverius).

Previous studies have validated the clinical use of opioids with μ-receptor affinities for pain management in raptors. Buprenorphine has a longer duration of action and minimal adverse effects when compared with other opioids in American kestrels ( Falco sparverius). To evaluate the thermal antinociceptive effects, sedative effects, and duration of action of sustained-release buprenorphine given intramusculary in American kestrels, 12 adult kestrels (8 females and 4 males) were used in a randomized masked complete-crossover experimental design. Buprenorphine SR LAB (1.8 mg/kg) or a control solution were administered intramuscularly. Foot withdrawal response to a thermal stimulus was determined 1 hour before (baseline) and at 1.5, 6, 12, 24, 48, and 72 hours after treatment administration. Agitation-sedation scores were determined 3-5 minutes before each time point, and adverse effects were monitored at these times. Buprenorphine SR LAB significantly increased thermal thresholds at 6, 12, and 24 hours and resulted in mild sedation according to the mean sedation-agitation scores comparing the treatment and control groups. Depending on the severity and type of pain, adjunctive therapy, and individual response, Buprenorphine SR LAB administered at 1.8 mg/kg IM to American kestrels would require administration every 24 hours to manage pain. Further pharmacodynamic and clinical evaluations are warranted in kestrels and other Falconiformes, Accipitriformes, and Strigiformes to establish accurate dosing recommendations.

Analgosedation Practices and the Impact of Sedation Depth on Clinical Outcomes Among Patients Requiring Mechanical Ventilation in the ED: Stephens RJ, Ablordeppey E, Drewry A, et al. Chest. 2017;152(5):963-971

Analgesia and sedation play critical roles in the treatment of mechanically ventilated patients, especially in the acute phase immediately following endotracheal intubation. In the intensive care unit (ICU) setting, deeper sedation early in a patient's time course has been associated with increased mortality and prolonged mechanical ventilation duration. For this reason, most intensivists aim for a Richmond Agitation-Sedation Score of -2 (awakens and makes eye contact to voice) to 0 (awake, alert and calm). However, there is a lack of such data for analgosedation initiated in the emergency department (ED), where critically ill patients are often intubated and managed early in their hospital course.

Effect and mechanism of dexmedetomidine on lungs in patients of sepsis complicated with acute respiratory distress syndrome

To investigate the mechanisms of protective effects of dexmedetomidine on lungs in patients of sepsis complicated with acute respiratory distress syndrome (ARDS). The adult patients with sepsis complicated with ARDS, the oxygenation index (PaO2/FiO2) was 150-200 mmHg (1 mmHg = 0.133 kPa), acute physiology and chronic health evaluation II (APACHE II) score was 10-20, need mechanical ventilation (MV) treatment > 72 hours, and admitted to intensive care unit (ICU) of the First Affiliated Hospital of Guangxi Medical University from September 2013 to June 2017 were enrolled. According to the random number table method, the patients were divided into three groups (n = 80): no sedation group, propofol group (0.3-4.0 mg×kg-1×h-1) and dexmedetomidine group (0.2-0.7 μg×kg-1×h-1). The three groups were adequately analgesic treated with remifentanil. The sedation target was -1-0 of Richmond agitation-sedation score (RASS). The levels of interlenkin-6 (IL-6) and tumor necrosis factor-α (INF-α) were determined by enzyme linked immunosorbent assay (ELISA) before sedation, and 24, 48, 72 hours after sedation. The expressions of inflammatory signaling proteins in bronchoalveolar lavage fluid (BALF) were determined by Western Blot before sedation and 72 hours after sedation. There were no significant changes for inflammatory factors in serum, and inflammatory signaling proteins and anti-apoptotic signaling proteins in alveolar exfoliated cells in no sedation group. The levels of IL-6 and TNF-α in serum and the expressions of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and phosphorylated c-Jun N-terminal kinase (p-JNK) in alveolar cells in propofol group and dexmedetomidine group were all significantly reduced after sedation, moreover, it was more significantly in the dexmedetomidine group compared with propofol group [48 hours: TNF-α (ng/L) was 153.76±29.16 vs. 179.82±30.28; 72 hours: IL-6 (ng/L) was 272.18±42.76 vs. 304.49±44.93, TNF-α (ng/L) was 102.18±30.25 vs. 140.28±28.92, TLR4 (IA value) was 0.288±0.034 vs. 0.648±0.029, MyD88 (IA value): 0.356±0.030 vs. 0.752±0.044, p-JNK (IA value): 0.256±0.027 vs. 0.303±0.034, all P < 0.05]. The expression of p-Akt in alveolar cells in propofol group and dexmedetomidine group was all significant increased after sedation, moreover, it was more significantly in the dexmedetomidine group compared with propofol group (IA value: 1.032±0.030 vs. 0.743±0.028, P < 0.05). Dexmedetomidine exerts the protective effects on lungs in patients of sepsis complicated with ARDS through the TLR4-MyD88-JNK signaling pathway.

Postoperative benefits of dexmedetomidine combined with flurbiprofen axetil after thyroid surgery.

The present study determined the effect of dexmedetomidine (Dex) combined with flurbiprofen axetil (FA) on analgesia, immune response, and preservation of cognitive function in patients subjected to general anesthesia. We recruited 100 patients with thyroid surgery and randomly divided them into four groups: Dex (D), FA (F), Dex combined with FA (DF), and saline control (C). The extubation and recovery times for Groups D and DF were significantly longer than for Groups F and C. After extubation, the heart rate and mean arterial pressure for Groups F, D, and DF were significantly lower than for Group C, and data for Group DF was significantly lower than for Group F. The visual analog scale and Riker sedation agitation scores were significantly lower in Group DF than for the other three groups. T- and B-lymphocytes were significantly higher in Group DF than in the other three groups. Compared with Groups F and C, the levels of TNF-α and IL-6 in Group DF were significantly reduced, while IL-2 markedly increased. The combined use of Dex and FA significantly improved pain after general anesthesia thyroid surgery, reduced restlessness and postoperative cognitive dysfunction, enhanced immune function, and promoted wound repair.

Sevoflurane sparing effect of dexmedetomidine in patients undergoing laparoscopic cholecystectomy: A randomized controlled trial.

Background and Aims:Sevoflurane is an excellent but expensive anesthetic agent for laparoscopic cholecystectomy. To decrease sevoflurane consumption during surgery adjuvants like dexmedetomidine may be used. Dexmedetomidine is a recently introduced drug which alleviates the stress response of surgery, produces sedation and analgesia. We aimed to evaluate sevoflurane sparing effect of dexmedetomidine in patients undergoing laparoscopic cholecystectomy under entropy-guided general anesthesia (GA).Material and Methods:In this prospective randomized control study, 100 American Society of Anesthesiologists physical status I–II adult surgical patients scheduled to undergo laparoscopic cholecystectomy were enrolled. Patients were randomly divided into two groups (n = 50). In dexmedetomidine group, patients received intravenous (IV) dexmedetomidine 0.5 μg/kg over 10 min before induction followed by 0.5 μg/kg/h infusion while in control group, patients received the same volume of normal saline.Results:Sevoflurane consumption was 41% lower in dexmedetomidine group as compared to control group (7.1 [1.6] vs. 12.1 [1.9] ml, P <0.001). A 40% reduction was observed in induction dose of propofol (83.0 [19.1] vs. 127.6 [24.8] mg, P <0.001). Mean Riker sedation-agitation score, visual analog score for pain and Aldrete's score were significantly lower in dexmedetomidine group as compared to control group. None of the patients experienced any significant side effects.Conclusion:A 41% reduction in sevoflurane consumption was observed in patients receiving IV dexmedetomidine as an adjuvant in patients undergoing laparoscopic cholecystectomy under GA.

Effectiveness of dexmedetomidine as premedication prior to electroconvulsive therapy, a Randomized controlled cross over study.

Background:This study evaluated the effect of dexmedetomidine on the acute hyperdynamic response, duration of seizure activity, and recovery profile in patients undergoing electroconvulsive therapy (ECT).Aims:To study the effectiveness of dexmedetomidine 1 μg/kg intravenous in ECT in terms of attenuation of the hyperdynamic response, seizures duration, and sedation.Design:This was a prospective, randomized, double-blinded, crossover study.Materials and Methods:Thirty patients were included in the study and were treated as both cases and controls. The study drug was given 10 min before induction of anesthesia. Vital parameters and recovery scores were recorded.Results:In Group D, heart rates at 3rd and 5th min after electric stimulus (T6 and T7, respectively) were 94.5 ± 20.1 and 90.4 ± 12.8/min as compared to 111.9 ± 15.5 and 109.0 ± 13.7 in Group N, respectively (P < 0.0001). The systolic blood pressure in Group D and Group N were 116.53 ± 26.09 and 138.03 ± 19.32 at T6, respectively (P < 0.001). Diastolic blood pressure and mean arterial pressure were significantly reduced after induction and electric stimulus in Group D. The seizures duration was similar in both groups. Modified Aldrete's Score and Richmond Agitation-Sedation Score were prolonged in Group D.Conclusion:Dexmedetomidine, before the induction of anesthesia, prevents the acute hyperdynamic responses to ECT without altering the seizures duration. However, patients may have delayed recovery and delayed discharge.

ICU Clinicians Underestimate Breathing Discomfort in Ventilated Subjects.

Breathing discomfort (dyspnea) during mechanical ventilation in the ICU may contribute to patient distress and complicate care. Assessment of nonverbal cues may allow caregivers to estimate patient breathing discomfort. This study assesses the accuracy of those caregiver estimates. Thirty subjects were identified from ventilated, hemodynamically stable patients in the special care unit of Maine Medical Center. Those with impaired neurological function or too unstable to waken were excluded. Subjects provided a subjective score of breathing discomfort (0-10 using a modified Borg scale) during daily wake-up from sedation (sedation-agitation score of 3 or 4). Clinicians (physicians, respiratory therapists, and nurses) then provided a blinded estimate of subject breathing discomfort (0-10) through observation of the subject and inspection of ventilator parameters alone. Subject scores and caregiver estimates were compared. All subjects reported breathing discomfort with median score (interquartile range) of 4 (3-4). Caregiver estimates of breathing discomfort were significantly lower than subject scores (2 [0-3]), and the discrepancy was seen in all professions (physicians 1 point lower [0-2], P = .02; respiratory therapists 1 point lower [0-2], P = .01; nurses 2 points lower [1-3], P < .001). There was a positive correlation between subject breathing discomfort and degree of underestimation (ie, the degree of underestimation increased as the subject scores rose). The 3 most commonly used cues were subjects' facial expression, use of accessory muscles, and nasal flaring. Significant breathing discomfort is prevalent in mechanically ventilated ICU patients and is underestimated by caregivers, regardless of profession. The increasing disparity in caregiver estimate as breathing discomfort rises may expose patients to levels of dyspnea that promote anxiety and fear. This study demonstrates the need for further development and standardization of methods to assess dyspnea in nonverbal patients.

Early deep sedation is associated with decreased in-hospital and two-year follow-up survival.

IntroductionThere is increasing evidence that deep sedation is detrimental to critically ill patients. The aim of this study was to examine effects of deep sedation during the early period after ICU admission on short- and long-term survival.MethodsIn this observational, matched-pair analysis, patients receiving mechanical ventilation that were admitted to ICUs of a tertiary university hospital in six consecutive years were grouped as either lightly or deeply sedated within the first 48 hours after ICU admission. The Richmond Agitation-Sedation Score (RASS) was used to assess sedation depth (light sedation: −2 to 0; deep: −3 or below). Multivariate Cox regression was conducted to investigate the impact of early deep sedation within the first 48 hours of admission on in-hospital and two-year follow-up survival.ResultsIn total, 1,884 patients met inclusion criteria out of which 27.2% (n = 513) were deeply sedated. Deeply sedated patients had longer ventilation times, increased length of stay and higher rates of mortality. Early deep sedation was associated with a hazard ratio of 1.661 (95% CI: 1.074 to 2.567; P = 0.022) for in-hospital survival and 1.866 (95% CI: 1.351 to 2.576; P <0.001) for two-year follow-up survival.ConclusionsEarly deep sedation during the first 48 hours of intensive care treatment was associated with decreased in-hospital and two-year follow-up survival. Since early deep sedation is a modifiable risk factor, this data shows an urgent need for prospective clinical trials focusing on light sedation in the early phase of ICU treatment.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-015-0929-2) contains supplementary material, which is available to authorized users.

Postanaesthetic emergence agitation in adult patients after general anaesthesia for urological surgery.

To investigate the incidence and risk factors for emergence agitation in the postanaesthetic care unit (PACU), in adult patients undergoing urological surgery. Medical records were retrospectively reviewed. Preoperative, intraoperative and postoperative variables were evaluated. Emergence agitation was defined as a Riker sedation-agitation score ≥ 5. Logistic regression analysis was used to determine independent risk factors for emergence agitation. Emergence agitation was observed in 48/488 (9.8%) patients. Chronic lung disease (odds ratio [OR] 2.72, 95% confidence interval [CI] 1.03, 7.17), duration of surgery (OR 1.01, 95% CI 1.00, 1.01), history of social drinking (OR 2.48, 95% CI 1.25, 4.93), postoperative pain score (OR 1.32, 95% CI 1.14, 1.53), voiding urgency (OR 2.20, 95% CI 1.01, 4.77) and presence of gastric tube (OR 2.85, 95% CI 1.07, 7.54) were independent risk factors for emergence agitation. Adequate postoperative pain management and prevention of catheter-related bladder discomfort may be helpful in reducing the incidence of emergence agitation in urology patients.

Evaluation of thermal antinociceptive effects and pharmacokinetics after intramuscular administration of butorphanol tartrate to American kestrels (Falco sparverius)

To evaluate antinociceptive effects and pharmacokinetics of butorphanol tartrate after IM administration to American kestrels (Falco sparverius). Fifteen 2- to 3-year-old American kestrels (6 males and 9 females). Butorphanol (1, 3, and 6 mg/kg) and saline (0.9% NaCl) solution were administered IM to birds in a crossover experimental design. Agitation-sedation scores and foot withdrawal response to a thermal stimulus were determined 30 to 60 minutes before (baseline) and 0.5, 1.5, 3, and 6 hours after treatment. For the pharmacokinetic analysis, butorphanol (6 mg/kg, IM) was administered in the pectoral muscles of each of 12 birds. In male kestrels, butorphanol did not significantly increase thermal thresholds for foot withdrawal, compared with results for saline solution administration. However, at 1.5 hours after administration of 6 mg of butorphanol/kg, the thermal threshold was significantly decreased, compared with the baseline value. Foot withdrawal threshold for female kestrels after butorphanol administration did not differ significantly from that after saline solution administration. However, compared with the baseline value, withdrawal threshold was significantly increased for 1 mg/kg at 0.5 and 6 hours, 3 mg/kg at 6 hours, and 6 mg/kg at 3 hours. There were no significant differences in mean sedation-agitation scores, except for males at 1.5 hours after administration of 6 mg/kg. Butorphanol did not cause thermal antinociception suggestive of analgesia in American kestrels. Sex-dependent responses were identified. Further studies are needed to evaluate the analgesic effects of butorphanol in raptors.

865

Introduction: Atypical antipsychotics, such as quetiapine, have been suggested as an option for treatment of intensive care unit related delirium by consensus guidelines and are being utilized more frequently in clinical practice as a component of sedation and agitation management in the critically ill. Methods: A retrospective chart review of patients receiving quetiapine in the surgical intensive care unit between May 1, 2010 and January 1, 2013 was conducted. Data collected included the frequency of documented agitation (Sedation Agitation Score > 4), duration of restraint use, and benzodiazepine requirements. Outcomes 72-hours previous to quetiapine administration were compared to outcomes 72-hours after the initiation of quetiapine. The prescribing pattern of quetiapine, including doses selected and duration of treatment, were also determined. Safety was evaluated by assessing the prevalence of QTc prolongation. Results: Seventy patients were included in this study. The median age was 67 years and 52 of the 70 patients (74%) were male. Forty-four (63%) patients were admitted to the surgical intensive care unit secondary to trauma with 34 (77%)of these patients having sustained a traumatic brain injury. On the day of quetiapine initiation, 47 (67%) patients were in some type of restraints. The median frequency of documented agitation was highest 24 hours before and after initiation of quetiapine. A decreasing trend was observed in the median daily benzodiazepines requirements. This effect was most pronounced in patients receiving greater than 10 mg per day of midazolam equivalents prior to quetiapine administration. In this subgroup (n=42), the median midazolam daily dose decreased from 28-mg to 2-mg. The median duration of restraint use was reduced by 24 hours from baseline. Half (35/70) of the patients were discharged from the surgical intensive care unit while receiving quetiapine and of these, two were discharged from the hospital while receiving quetiapine. Three patients experienced a QTc interval greater than 500 msec with no episodes of torsades de pointes noted during the study period. Conclusions: Quetiapine administration may reduce benzodiazepine requirements and duration of restraint use. There is a high prevalence of continuation of quetiapine beyond the intensive care unit environment. This is a potential area for quality improvement with regards to medication reconciliation, limiting adverse effects, drug interactions, and cost. QTc interval should be monitored in patients receiving quetiapine.

A Randomized, Double-Blind Pilot Study of Dexmedetomidine Versus Midazolam for Intensive Care Unit Sedation

Sedation with dexmedetomidine may facilitate ventilator liberation and limit the occurrence of delirium. No trial has assessed patient recall or the development of psychological outcomes after dexmedetomidine sedation. This pilot study evaluated whether transitioning benzodiazepine sedation to dexmedetomidine alters patient recall and the incidence of anxiety, depression, or acute stress disorder (ASD). This investigation was a randomized, double-blind, single-center study. Existing continuous benzodiazepine sedation was converted to dexmedetomidine or midazolam when patients qualified for daily awakenings. Sedation was titrated to achieve Riker sedation agitation scores of 3 to 4. The intensive care unit (ICU) Stressful Experiences Questionnaire, hospital anxiety and depression scale, and the impact of event scale-revised were administered before hospital discharge to assess recall, anxiety, depression, and manifestations of ASD. A total of 11 patients received dexmedetomidine, and 12 patients received midazolam. Median dosing was 0.61 µg/kg/h for 3.5 days for dexmedetomidine and 3.7 mg/h for 3 days for midazolam. Attainment of goal sedation and analgesia was similar; however, more dexmedetomidine patients experienced agitation and pain. The median duration of mechanical ventilation from study drug initiation to extubation was 3.4 days in dexmedetomidine patients and 2.9 days in midazolam patients. Dexmedetomidine patients remembered 18.5 experiences compared with 8.5 in midazolam patients (P = .015). Rates of anxiety and depression were similar. In all, 5 (62.5%) dexmedetomidine patients and 1 (12.5%) midazolam patient manifested ASD (P = .063), and 1 dexmedetomidine patient and 5 midazolam patients developed new-onset delirium (P = .07). Hypotension occurred in 10 (90.9%) dexmedotomidine patients and 6 (50%) midazolam patients (P = .069). Transitioning benzodiazepine sedation to dexmedetomidine when patients qualify for daily awakenings may reduce the development of delirium and facilitate remembrance of ICU experiences but may lead to manifestations of ASD. Monitoring hypotension is required for both the sedatives. Additional comparative studies focusing on the long-term impact of ICU recall and psychological outcomes are needed.

Use of Sedation and Neuromuscular Blockers in Critically Ill Adults Receiving High-Frequency Oscillatory Ventilation

Nearly all patients receive sedation and neuromuscular blockers (NMBs) during high-frequency oscillatory ventilation (HFOV). To describe analgo-sedation and NMB use prior to and during HFOV in adults with acute respiratory distress syndrome. Retrospective single-center study of 131 consecutive adults whose care was managed with HFOV from 2002 to 2011. During the first 4 days of HFOV, 89% and 95% of patients received sedation and opioids, respectively. Upon HFOV initiation, 119 (90.8%) patients received fentanyl doses higher than 200 µg/h; of these, 48 also received more than 20 mg/h of midazolam. Analgo-sedation doses increased significantly over time such that doses were double by day 3. Factors independently associated with fentanyl doses higher than 200 µg/h were NMB ever used (OR 4.43; 95% CI 1.26-15.65, p = 0.02), pH less than 7.15 (OR 2.08; 95% CI 1.22-3.5, p = 0.007), worsening partial pressure of oxygen/fraction of inspired oxygen (OR 1.05; 95% CI 1.00-1.10, p = 0.04), and Acute Physiology and Chronic Health Evaluation (APACHE) II score (OR 0.87; 95% CI 0.79-0.97, p = 0.009). Deep sedation was commonly administered when NMBs were not being used, with 99.2% of sedation-agitation scores of 1 or 2. Eighty-six patients (65.6%) received NMBs and use was greatest on day 1 (59.5%). Train-of-Four was measured every hour for 53.4% of patients; 29.2% of the measurements were 0 of 4. NMB use declined over the 10-year study period. High analgo-sedation doses were associated with APACHE II scores, worsening gas exchange, and NMB use. Two thirds of patients received NMBs; use was highest on day 1 and subsequently declined. The percentage of patients who received NMB during HFOV in our study was lower than that previously reported. Future research should evaluate patient outcomes with and without use of NMBs, as well as the potential to manage patients with less sedation.

Evaluation of thermal antinociceptive effects after intramuscular administration of hydromorphone hydrochloride to American kestrels (Falco sparverius)

To evaluate the antinociceptive and sedative effects and duration of action of hydromorphone hydrochloride after IM administration to American kestrels (Falco sparverius). 11 healthy 2-year-old American kestrels. Hydromorphone (0.1, 0.3, and 0.6 mg/kg) and an equivalent volume of saline (0.9% NaCl) solution (control treatment) were administered IM to kestrels in a masked randomized complete crossover study design. Foot withdrawal response to a thermal stimulus was determined 30 to 60 minutes before (baseline) and 0.5, 1.5, 3, and 6 hours after treatment administration. Agitation-sedation scores were determined 3 to 5 minutes before each thermal test. Hydromorphone at 0.6 mg/kg, IM, significantly increased the thermal foot withdrawal threshold, compared with the response after administration of saline solution, for up to 3 hours, and hydromorphone at 0.1, 0.3, and 0.6 mg/kg, IM, significantly increased withdrawal responses for up to 6 hours, compared with baseline values. No significant differences in mean sedation-agitation scores were detected between hydromorphone and saline solution treatments; however, appreciable sedation was detected in 4 birds when administered 0.6 mg of hydromorphone/kg. Hydromorphone at the doses evaluated significantly increased the thermal nociception threshold for American kestrels for 3 to 6 hours. Additional studies with other types of stimulation, formulations, dosages, routes of administration, and testing times are needed to fully evaluate the analgesic and adverse effects of hydromorphone in kestrels and other avian species and the use of hydromorphone in clinical settings.

Bispectral Index Values, Sedation-Agitation Scores, and Plasma Lorazepam Concentrations in Critically Ill Surgical Patients

Publications on the use of the bispectral index for sedation monitoring in the intensive care unit are increasing. However, few studies have involved correlation of bispectral index with serum drug concentrations. To assess the degree of correlation between bispectral index values, scores on the Sedation-Agitation Scale, and steady-state serum concentrations of lorazepam. A prospective open-label study of patients in a surgical intensive care unit who were receiving mechanical ventilation and continuous infusions of lorazepam for more than 24 hours. Bispectral index was measured (BIS-XP, Aspect Medical, Norwood, Massachusetts) to assess patients' sedation. Sensors were applied and values recorded before and after stimulation (endotracheal suctioning). Concomitant plasma samples were obtained to measure lorazepam concentration and scores on the Sedation-Agitation Scale were recorded. Sixteen patients were studied. Correlations between plasma concentrations of lorazepam and measurements of bispectral index for 1, 2, and 3 minutes before endotracheal stimulation were poor (0.21, 0.29, and 0.25, respectively). Correlation of peak values for bispectral index (after stimulation) with plasma concentrations of lorazepam was 0.29. Correlations of scores on the Sedation-Agitation Scale with the aforementioned values for bispectral index were similarly poor. Area under the curve for bispectral index values also correlated poorly with plasma concentration of lorazepam (0.19) and score on the Sedation-Agitation Scale (0.10). The correlation between bispectral index and score on the Sedation-Agitation Scale was poor. Correlation between bispectral index and plasma concentration of lorazepam was modestly better, but insufficient for clinical utility.

Use of Airway Pressure Release Ventilation is Associated With a Reduced Incidence of Ventilator-Associated Pneumonia in Patients With Pulmonary Contusion

Past studies suggest that airway pressure release ventilation (APRV) is associated with reduced sedative requirements and increased recruitment of atelectatic lung, two factors that might reduce the risk for ventilator-associated pneumonia (VAP). We investigated whether APRV might be associated with a decreased risk for VAP in patients with pulmonary contusion. Retrospective cohort study. Of 286, 64 (22%) patients requiring mechanical ventilation for >48 hours met criteria for pulmonary contusion and were the basis for this study. Subjects with pulmonary contusion had a significantly higher rate of VAP than other trauma patients, [VAP rate contusion patients: 18.3/1,000, non-contusion patients: 7.7/1,000, incidence rate ratio 2.37 (95% confidence interval [CI], 1.11-4.97), p=0.025]. Univariate analysis showed that APRV (hazard ratio, 0.15 [0.03-0.72; p=0.018]) was associated with a decreased incidence of VAP. Cox proportional hazards regression, using propensity scores for APRV to control for confounding, supported a protective effect of APRV from VAP (hazard ratio, 0.10 [95% CI, 0.02-0.58]; p=0.01). Pao2/FiO2 ratios were higher during APRV compared with conventional ventilation (p<0.001). Subjects attained the goal Sedation Agitation Score for an increased percentage of time during APRV (median [interquartile range (IQR)] 72.7% [33-100] of the time) compared with conventional ventilation (47.2% [0-100], p=0.044), however, dose of sedatives was not different between these subjects. APRV was not associated with hospital mortality (odds ratio 0.57 [95% CI, 0.06-5.5]; p=0.63) or ventilator-free days (No APRV 15.4 vs. APRV 13.7 days, p=0.49). Use of APRV in patients with pulmonary contusion is associated with a reduced risk for VAP.

Remifentanil-propofol analgo-sedation shortens duration of ventilation and length of ICU stay compared to a conventional regimen: a centre randomised, cross-over, open-label study in the Netherlands

Compare duration of mechanical ventilation (MV), weaning time, ICU-LOS (ICU-LOS), efficacy and safety of remifentanil-based regimen with conventional sedation and analgesia. Centre randomised, open-label, crossover, 'real-life' study. 15 Dutch hospitals. Adult medical and post-surgical ICU patients with anticipated short-term (2-3 days) MV. Patient cohorts were randomised to remifentanil-based regimen (n = 96) with propofol as required, for a maximum of 10 days, or to conventional regimens (n = 109) of propofol, midazolam or lorazepam combined with fentanyl or morphine. Outcomes were weaning time, duration of MV, ICU-LOS, sedation- and analgesia levels, intensivist/ICU nurse satisfaction, adverse events, mean arterial pressure, heart rate. Median duration of ventilation (MV) was 5.1 days with conventional treatment versus 3.9 days with remifentanil (NS). The remifentanil-based regimen reduced median weaning time by 18.9 h (P = 0.0001). Median ICU-LOS was 7.9 days versus 5.9 days, respectively (NS). However, the treatment effects on duration of MV and ICU stay were time-dependent: patients were almost twice as likely to be extubated (P = 0.018) and discharged from the ICU (P = 0.05) on day 1-3. Propofol doses were reduced by 20% (P = 0.05). Remifentanil also improved sedation-agitation scores (P < 0.0001) and intensivist/ICU nurse satisfaction (P < 0.0001). All other outcomes were comparable. In patients with an expected short-term duration of MV, remifentanil significantly improves sedation and agitation levels and reduces weaning time. This contributes to a shorter duration of MV and ICU-LOS.