The second Austrian benchmark study for blood use in elective surgery: results and practice change.

BACKGROUND: Five years after the first Austrian benchmark study demonstrated relatively high transfusion rate and an abundance of nonindicated transfusions in elective surgeries, this study was conducted to investigate the effects of the first benchmark study. STUDY DESIGN AND METHODS: Data from 3164 patients undergoing primary unilateral total hip replacement (THR), primary unilateral noncemented total knee replacement (TKR), or coronary artery bypass graft (CABG) surgery at 15 orthopedic and six cardiac centers were collected and compared with the first study. RESULTS: Transfusion rates decreased in THR (41% to 30%) and TKR (41% to 25%), but remained unchanged in CABG surgery (57% vs. 55%) compared with the first study. More than 80% of all transfusions involved at least 2 units of red blood cells (RBCs). Marked variations were observed in transfusion rates among the centers. The prevalence of anemia was three times higher in patients who received transfusions versus those who did not. However, preoperative anemia was left untreated in the majority of patients. A considerable intercenter variability of RBC loss ranging from 26% to 43% in THR, from 24% to 40% in TKR, and from 30% to 49% in CABG procedures was observed. CONCLUSION: The second benchmark study demonstrates substantial intercenter variability and small but significant reductions in RBC transfusions and RBC loss. Even though the main independent predictors of transfusion were the relative lost RBC volume followed by the relative preoperative and the lowest relative postoperative hemoglobin, preoperative anemia was not adequately treated in many patients, underscoring the importance of patient blood management in these patients.

BIS-vista occipital montage in patients undergoing neurosurgical procedures during propofol-remifentanil anesthesia.

BACKGROUND: Neurosurgical procedures that require a frontal approach could be an impediment for a successful Bispectral Index (BIS) frontal sensor placement. The aim of this study was to explore the utility of using the new BIS-Vista monitor (Aspect Medical Systems, Newton, MA) for occipital sensor placement in the patients undergoing brain neurosurgical procedures during propofol-remifentanil anesthesia. METHODS: Two BIS Quatro sensors (Aspect Medical Systems, Newton, MA) mounted on the occipital and frontal regions were connected to two BIS-Vista monitors at three anesthesia states: before induction, during anesthesia maintenance, and recovery. RESULTS: There were significant differences before induction (P = 0.0002) and at anesthesia maintenance (P = 0.0014) between mean +/- SD occipital (83.4 +/- 4.8, 66.7 +/- 7.2) and frontal (93.1 +/- 3.4, 56.9 +/- 9.1) BIS-Vista values. During anesthesia recovery, there was no difference (P = 0.7421) between occipital (54.6 +/- 9.3) and frontal (53.1 +/- 7.3) BIS-Vista values. Bland and Altman analysis revealed a BIS-Vista negative-bias (limits of agreement) of -9.7 (+1.1, -20.5) before anesthesia induction, +9.8 positive-bias (+22.8, -1.7) during anesthesia maintenance, and -0.9 bias (+10.9, -12.8) during anesthesia recovery. CONCLUSION: We demonstrated that not only the regional limits of agreement are too wide to allow data of the two montages to be used interchangeably but also the variation is a function of anesthetic depth. However, keeping in mind a relatively consistent BIS-Vista -10 bias before induction and +10 bias during anesthesia maintenance with limits of agreement of approximately +/-11 BIS units, approximately double the clinically acceptable less than 10 BIS units level of agreement, BIS-Vista off-label occipital montage might be helpful in following a trend of propofol-remifentanil anesthesia in individual cases where frontal access is particularly difficult.

Measurement of cardiac output and pulmonary transit time for assessment of pulmonary vascular resistance in domestic piglets.

The degree of elevated pulmonary vascular resistance (PVR) is a crucial clinical parameter. Cardiac output (CO) and pulmonary transit time (PTT) can be ascertained by a number of radiological methods. A close functional relationship between CO, PTT and PVR would facilitate non-invasive PVR measurements. One-hundred and fifty-one measurements were made in six piglets. Pressures in the pulmonary and systemic circulation were measured invasively. Cardic output was determined by the use of a Doppler flow probe around the truncus pulmonalis. Temperature sensors were placed in the pulmonary truncus and left atrium. Elevated PVR was produced by repeated air embolism. After injection of ice-cold saline, the time span between the minimal temperature in the truncus pulmonalis and the left atrium was taken as PTT. The CO and PTT were inserted into a new formula derived from the Hagen-Poiseuille law for the calculation of the PVR model. Numerical constants of the formula were calculated by the robust method of minimization. The PVR values, as calculated from invasively measured mean pulmonary artery pressure, mean left atrial pressure and CO, served as reference. In the six piglets, the PVR model and PVR reference showed a strong linear correlation with r = 0.923. The Bland-Altman plot revealed a standard deviation of -0.64/+0.67 Wood units. Cardiac output, PTT and PVR showed a close functional relationship. With a correction for blood viscosity and body size, this relationship could be used for non-invasive clinical measurements of PVR.

Effect of flumazenil on bispectral index monitoring in unpremedicated patients.

BACKGROUND: Flumazenil is an imidazobenzodiazepine that promptly reverses via competitive inhibition the hypnotic/sedative effects of benzodiazepines on gamma-aminobutyric acid receptors. Endogenous benzodiazepine ligands (endozepines) were isolated in urine, cerebrospinal fluid, and breast milk of women who had not received benzodiazepines. The bispectral index (BIS), an electroencephalographically derived parameter widely used for monitoring the effects of anesthetic/hypnotic drugs, was shown to correlate to various conditions that could influence electroencephalography. The authors examined the hypothesis that 0.5 mg of flumazenil administered to healthy unpremedicated patients during deep surgical remifentanil/propofol anesthesia would increase the BIS value and might expedite recovery from anesthesia. METHODS: Sixty healthy unpremedicated patients were randomly allocated to the flumazenil or control groups. After study drug administration, the authors compared BIS values and various recovery parameters in the flumazenil and control groups. RESULTS: BIS baseline values in the flumazenil group (38.7 +/- 3.8) increased 15 min after flumazenil administration (53.2 +/- 4.7), with a significant difference over time (P < 0.0001) between the two groups. Mean recovery parameters time, comprising time to spontaneous breathing, eye opening/hand squeezing on verbal command, extubation, and date of birth recollection, was significantly shorter (P = 0.0002) in the flumazenil group (6.9 +/- 2.6 min) compared with the control group (9.8 +/- 2.9 min). CONCLUSIONS: This study demonstrates that flumazenil given to healthy unpremedicated patients during propofol/remifentanil anesthesia significantly increased the BIS value and allowed earlier emergence from anesthesia. This may indicate that flumazenil could be used on a case-by-case basis to reverse endogenous or exogenous endozepines that might play a role during anesthesia.

Psychological and systemic stress reactions of patients during hyperthermia treatments.

PURPOSE: This study evaluated psychological stress reactions during hyperthermia (HT) treatments and compared them to systemic stress reactions. MATERIALS AND METHODS: 27 patients with malignant disease were treated with superficial or regional hyperthermia. Cortisol and the catecholamines adrenaline and noradrenaline in venous blood were used as markers of psychological stress. The anxiety proneness of the patients was evaluated with a trait-anxiety inventory. Blood pressure and heart rate were markers of systemic stress. Patients were first grouped by superficial or regional treatment and then into two subgroups: anxious and non-anxious patients. RESULTS: The time course of the cortisol concentration of the superficial group showed a slight but significant decrease and that of the regional group an increase. The cortisol concentration of the regional group was sometimes slightly but significantly higher than in the superficial group, and in the group of anxious patients higher than in the group of non-anxious patients. The changes in time courses and differences in groups were not as pronounced for the catecholamine concentrations. Heart rate and blood pressure showed a significant increase only in the regional group, and there was no significant difference between the regional and the superficial groups. None of the variables showed a significant difference between the initial and the subsequent treatments; all lay well within the normal physiological range. CONCLUSIONS: These standard hyperthermia treatments are not excessively stressful, either systemically or psychologically. The different behaviours of the variables confirm that it makes sense to consider systemic stress as well as psychological reactions.

Bispectral-index-guided versus clinically guided remifentanil/propofol analgesia/sedation for interventional radiological procedures: an observer-blinded randomized study.

Patients undergoing potentially painful interventional radiological procedures generally require a combination of analgesia and sedation. This sedation/analgesia should allow the patient to communicate while also remaining calm. Bispectral index (BIS) monitoring could be useful in achieving this. The primary end-point of our study was to compare the percentage time with optimal sedation, defined as Sedation Agitation Scale (SAS) grade 4, between a BIS-guided remifentanil/propofol regimen and a clinically guided regimen in 54 randomly allocated patients. The mean +/- sd percentage time with optimal sedation was significantly longer (P = 0.004) in the BIS group (76.6% +/- 14.7%) than in the SAS group (63.8% +/- 16.4%). There was a significant difference in the weighted mean infusion rates of remifentanil (P = 0.0067) and propofol (P = 0.0075) in the BIS group (0.066 +/- 0.027 microg.kg(-1) . min(-1) 1.59 +/- 0.44 mg.kg(-1) . h(-1)) compared with the SAS group (0.091 +/- 0.036 microg.kg(-1).min(-1) 1.92 +/- 0.43 mg.kg(-1).h(-1)), respectively. BIS values exhibited a temporal correlation to SAS scores (r2 = 0.72). In conclusion, a BIS-guided regimen was more effective than a SAS-guided regimen. The use of BIS resulted in fewer remifentanil and propofol doses. The targeted BIS range of 80-85 provided a sufficient functional level of sedation.

Procalcitonin and C-reactive protein plasma concentrations in nonseptic uremic patients undergoing hemodialysis.

OBJECTIVE: To assess procalcitonin (PCT) and C-reactive protein (CRP) plasma concentrations and clearance in nonseptic end-stage renal failure patients undergoing their first three hemodialysis sessions. DESIGN AND SETTING: Prospective observational consecutive clinical study at a university hospital. PATIENTS: The study recruited 55 end-stage renal failure patients without evidence of systemic infection undergoing the creation of an arteriovenous fistula to start hemodialysis for the first time. INTERVENTIONS: Blood samples were collected before and after each of the first three (4-5 h) hemodialysis sessions. PCT was assayed by immunoluminometry. MEASUREMENTS AND RESULTS: The mean plasma concentration of PCT prior to the first three hemodialysis sessions declined significantly following each session. There was no significant difference between CRP plasma concentrations before and after hemodialysis sessions. CONCLUSIONS: The presence of an elevated PCT in plasma of not yet dialyzed uremic nonseptic patients indicates that uremia per se and not the dialysis process is the origin of such elevation. PCT levels declined with successive hemodialysis sessions. We propose that in the not yet dialyzed uremic nonseptic patients a baseline PCT level of approx. 1.5 ng/ml should be expected. Although the mean plasma CRP level was elevated, hemodialysis had no significant effect on CRP concentration, making CRP a possible useful marker of sepsis in these patients.

Indirect versus direct laryngoscopy for routine nasotracheal intubation.

STUDY OBJECTIVE: To compare the effectiveness of the indirect laryngoscopes, Airtraq (A) and GlideScope (G), with the Macintosh (M) laryngoscope in routine nasotracheal intubation. DESIGN: Randomized, single-blinded study. SETTING: University-affiliated, tertiary-care hospital. PATIENTS: 62 adult, ASA physical status 1 and 2 patients with normal airways requiring nasotracheal intubation for dental or maxillofacial surgery. INTERVENTION: Patients in Groups A and G underwent nasal intubation with the Airtraq and GlideScope, respectively, while laryngoscopy in Group M was performed with the Macintosh blade. MEASUREMENTS: Performance of the intubating tools was judged by the ease [Intubation Difficulty Scale (IDS) and numeric rating scale (NRS)] and time to intubation (laryngoscopy and endotracheal tube advancement). In addition, hemodynamic parameters, severity of postoperative sore throat, and posture of the intubator were recorded. MAIN RESULTS: IDS score was significantly lower with the Airtraq and GlideScope than with the Macintosh laryngoscope (mean ± SD: A 0.1 ± 0.3, G 0.3 ± 0.6, M 0.8 ± 1.0; P = 0.013). NRS reported by the intubators showed a similar preference for indirect over direct laryngoscopy (A 0.9 ± 0.7, G 1.1 ± 0.6, M 1.9 ± 1.1; P = 0.001). Duration of laryngoscopy and endotracheal tube insertion was similar in all groups. No significant intergroup differences in hemodynamic parameters were recorded. Postoperative sore throat was significantly reduced using the GlideScope compared with the other devices (P = 0.048). CONCLUSION: The Airtraq and GlideScope facilitated nasotracheal intubation more so than the Macintosh laryngoscope in adults with apparently normal airways.

The utility of using the bispectral index-Vista for detecting cross-clamping decline in cerebral blood flow velocity.

BACKGROUND: Patients undergoing carotid endarterectomy for extracranial internal carotid artery stenosis are at risk of cerebral ischemia/hypoperfusion. Criterion recommended by European and American committees to determine whether to place a shunt consisted of a decline in transcranial Doppler ultrasonography-measured middle cerebral artery blood flow velocity (MCBFV) to < 30% to 40% of intraoperative preclamp value. OBJECTIVE: To assess the discriminative power of the bispectral index (BIS)-Vista monitor for detecting a 40% decline in MCBFV with cross-clamping. METHODS: In 20 patients undergoing carotid endarterectomy under remifentanil/propofol anesthesia, BIS-Vista data, MCBFV, and pulsatility index from bilaterally mounted BIS-Vista and transcranial Doppler monitors were continuously recorded. RESULTS: Coefficient of determination revealed good correlation (r = 0.763) between ipsilateral BIS-Vista and MCBFV after cross-clamping. BIS-Vista exhibited a high discriminative power of 0.850 (95% confidence interval, 0.455-0.966) area under the receiver-operating characteristic curve in detecting an ipsilateral 40% MCBFV decline. Two-way analysis of variance (location by time) suggests that BIS-Vista exhibited a global decline; ie, both BIS-Vistas declined when 1 carotid on either side was clamped because there was no significant interhemispheric difference (P = .112) in mean BIS-Vista values over time. CONCLUSION: Although we demonstrated good correlation and high discriminative power of the BIS-Vista monitor in depicting a MCBFV decline that could serve as indicator of decline in cerebral activity, BIS-Vista cannot be considered a reliable indicator of cerebral ischemia/hypoperfusion that could replace transcranial Doppler monitoring to determine whether a shunt is to be placed.

No midterm benefit from low intensity pulsed ultrasound after chevron osteotomy for hallux valgus.

Chevron osteotomy is a widely accepted method for correction of symptomatic hallux valgus deformity. Full weight bearing in regular shoes is not recommended before 6 weeks after surgery. Low intensity pulsed ultrasound is known to stimulate bone formation leading to more stable callus and faster bony fusion. We performed a randomized, placebo-controlled, double-blinded study on 44 participants (52 feet) who underwent chevron osteotomy to evaluate the influence of daily transcutaneous low intensity pulsed ultrasound (LIPUS) treatment at the site of osteotomy. Follow-up at 6 weeks and 1 year included plain dorsoplantar radiographs, hallux-metatarsophalangeal-interphalangeal scale and a questionnaire on patient satisfaction. There was no statistical difference in any pre- or postoperative clinical features, patient satisfaction or radiographic measurements (hallux valgus angle, intermetatarsal angle, sesamoid index and metatarsal index) except for the first distal metatarsal articular angle (DMAA). The DMAA showed statistically significant (p = 0.046) relapse in the placebo group upon comparison of intraoperative radiographs after correction and fixation (5.2 degrees) and at the 6-week follow-up (10.6 degrees). Despite potential impact of LIPUS on bone formation, we found no evidence of an influence on outcome 6 weeks and 1 year after chevron osteotomy for correction of hallux valgus deformity.

Effect of somatostatin analogue octreotide on pain relief after major abdominal surgery.

BACKGROUND: Octreotide acetate is an 8-amino-acids synthetic octapeptide analogue of somatostatin with much-enhanced duration of action and lower incidence of side effects. We assessed the utility of using intravenous octreotide as an adjuvant to opioid analgesia that might exert a post-operative opioid-sparing effect. METHODS: Forty-four patients were randomly allocated, to receive either a placebo or intraoperative octreotide 0.33 microg kg(-1)h(-1) intravenous infusion that was maintained in the post-operative period. Patients received for post-operative analgesia an intravenous piritramide patient controlled analgesia (PCA), set to deliver a piritramide 0.02 mgkg(-1) dose. RESULTS: Two-way ANOVA revealed significantly fewer (P=0.0003) mean+/-SD weighted piritramide dose requirements in the octreotide group (19.5+/-6.3 microg kg(-1)h(-1)) than in the control group (35.7+/-8.2 microg kg(-1)h(-1)). Dunnett's two-sided multiple-comparison post hoc test revealed a significant difference between the two groups during the first 22 post-operative hours, following which there were no differences between the two groups. There were no significant differences over time in the mean arterial pressure (P=0.722), heart rate (P=0.579) and respiratory rate (P=0.823) between the octreotide group (80+/-10mm Hg, 74+/-12, 14+/-2) and the control group (82+/-9 mm Hg, 76+/-11, 15+/-3), respectively. CONCLUSION: We demonstrated that perioperative octreotide intravenous infusion could be an adjuvant to opioid analgesia as it exerted a piritramide opioid-sparing effect. We encountered more systemic side effects such as nausea, abdominal discomfort, and diarrhea in the octreotide group than in the control group. Our findings could be beneficial to patients who cannot tolerate the adverse effects of opioids.

Blood use in elective surgery: the Austrian benchmark study.

BACKGROUND: Benchmarking transfusion activity may help to eliminate inappropriate use of blood products. The goal of this study was to measure and to compare the current transfusion practice and to identify predictors of transfusion in public hospitals to develop strategies to optimize transfusion practices. STUDY DESIGN AND METHODS: This was a prospective observational study in 18 randomly selected public hospitals from April 2004 to February 2005. Primary outcome measures were the amount of intra- and postoperative blood components transfused and intercenter variability of transfusion rate. Secondary outcome measures were prevalence of preoperative anemia, calculated perioperative blood loss, and lowest measured perioperative hemoglobin (Hb) level. RESULTS: Adult patients undergoing primary unilateral total hip replacement (THR, n = 1401), primary unilateral knee replacement (TKR, n = 1296), hemicolectomy (HECOC, n = 148), and coronary artery bypass graft (CABG) surgery (n = 777) were enrolled. Due to the small number, data of HECOC patients were not fully analyzed. In the remaining procedures, there was a large intercenter variability in the percentage of patients who received transfusions: THR 16 to 85 percent, TKR 12 to 87 percent, and CABG 37 to 63 percent. In the patients who received transfusions, the number of red blood cells (RBC) units transfused varied significantly. There was also a considerable intercenter variability in RBC loss. The prevalence of preoperative anemia was 19 percent and identical in both sexes. The incidence of preoperative anemia was three times higher in patients who received transfusions compared to those who did not. CONCLUSION: This study demonstrates a high intercenter variability in RBC transfusions and RBC loss in standard surgical procedures. Whereas the variability in blood loss remains largely unexplained, the main predictors for allogeneic RBC transfusions are preoperative and nadir Hb and surgical RBC loss.

Geographic regional differences in rocuronium bromide dose-response relation and time course of action: an overlooked factor in determining recommended dosage.

BACKGROUND: Geographic location is not acknowledged as a stratifying factor that can directly affect drug potency, because drugs are still licensed with the same recommended dose for different geographic regions. The aim of the current study was to compare the potency and duration of action of rocuronium bromide in 54 patients in three countries with different life habits, diet, and ambient conditions, namely white Austrians, white North Americans, and Han Chinese in China. METHODS: Neuromuscular block of six consecutive 50-microg/kg rocuronium incremental doses followed by 300 microg/kg was evaluated using the Relaxometer mechanomyograph (Groningen University, Groningen, Holland). Dose-response curves were created using log-dose-probit transformation. The authors compared rocuronium bromide ED50, ED90, and ED95 (effective doses required for 50%, 90%, and 95% first twitch depression, respectively) as well as Dur25 and Dur0.8 (times from last incremental dose administration until 25% first twitch and 0.8 train-of-four ratio recovery, respectively) in patients of the three countries. RESULTS: Rocuronium ED50, ED90, and ED95 were significantly higher in Austrian patients (258 +/- 68, 530 +/- 159, and 598 +/- 189 microg/kg) and Chinese patients (201 +/- 59, 413 +/- 107, and 475 +/- 155 microg/kg) compared with American patients (148 +/- 48, 316 +/- 116, and 362 +/- 149 microg/kg, respectively). Dur25 and Dur0.8 were significantly shorter in Austrian patients (22.3 +/- 5.5 and 36.9 +/- 12.8 min) and Chinese patients (30.4 +/- 7.5 and 45.7 +/- 15.9 min) compared with American patients (36.7 +/- 8.5 and 56.2 +/- 16.7 min, respectively). CONCLUSIONS: The authors demonstrated a significant difference in rocuronium potency and duration of action among patients in the three countries. Larger studies are required for determining dosage recommendations for different geographic regions.

[The effect of a homeopathic drug on the blood pressure of hypertensive patients--a randomised double-blind controlled parallel group comparative trial]. / Zur Wirkung eines homöopathischen Fertigarzneimittels auf den Blutdruck von Hypertonikern. Eine randomisierte doppelblinde kontrollierte Parallelgruppen-Vergleichsstudie.

Pumpan in a dosage of 3 x 10 drops daily over 6 weeks does not differ in its effect on systolic and diastolic blood pressure significantly from placebo. The tolerance was excellent: not one single patient had to be withdrawn from the study due to side effects. Blood lipids (cholesterol, HDL-, LDL-cholesterol and triglyzerides) did not change, neither in the placebo nor in the verum group.

Remifentanil versus morphine analgesia and sedation for mechanically ventilated critically ill patients: a randomized double blind study.

BACKGROUND: The rapid onset and offset of action of remifentanil could make it quickly adjustable to the required level of sedation in critically ill patients. The authors hypothesized that the efficacy of a remifentanil-based regimen was greater than that of a morphine-based regimen. METHODS: Forty intent-to-treat patients were randomly allocated to receive a blinded infusion of either remifentanil 0.15 microg x kg(-1) x min(-1) or morphine 0.75 microg x kg(-1) x min(-1). The opioid infusion was titrated, in the first intent, to achieve optimal sedation defined as Sedation Agitation scale of 4. A midazolam open-label infusion was started if additional sedation was required. RESULTS: The mean percentage hours of optimal sedation was significantly longer in the remifentanil group (78.3 +/- 6.2) than in the morphine group (66.5 +/- 8.5). This was achieved with less frequent infusion rate adjustments (0.34 +/- 0.25 changes/h) than in the morphine group (0.42 +/- 0.22 changes/h). The mean duration of mechanical ventilation and extubation time were significantly longer in the morphine group (18.1 +/- 3.4 h, 73 +/- 7 min) than in the remifentanil group (14.1 +/- 2.8 h, 17 +/- 6 min), respectively. Remifentanil mean infusion rate was 0.13 +/- 0.03 microg x kg(-1) x min(-1), whereas morphine mean infusion rate was 0.68 +/- 0.28 microg x kg(-1) x min(-1). More subjects in the morphine group (9 of 20) than in the remifentanil group (6 of 20) required midazolam. The incidence of adverse events was low and comparable across the two treatment groups. CONCLUSIONS: A remifentanil-based regimen was more effective in the provision of optimal analgesia-sedation than a standard morphine-based regimen. The remifentanil-based regimen allowed a more rapid emergence from sedation and facilitated earlier extubation.

The neuromuscular transmission module versus the relaxometer mechanomyograph for neuromuscular block monitoring.

UNLABELLED: The neuromuscular transmission module (M-NMT) is an integrated piezoelectric motion sensor module incorporated in the AS/3(TM) anesthesia monitor. We compared the neuromuscular block of 0.6 mg/kg rocuronium (twice the 95% effective dose) monitored by the M-NMT with that monitored by the Relaxometer mechanomyograph (MMG). The two monitors were alternately allocated to the left or right hands of 20 patients. T(1)%, the first twitch of the train-of-four (TOF), and the TOF ratio (T(4)/T(1)) were used for evaluating the neuromuscular block. There was no significant difference in the mean (min) plus minus SD onset time or time to 0.8 TOF ratio recovery measured by the M-NMT (1.5 plus/minus 0.3, 49.4 plus/minus 8.1) compared with MMG (1.8 plus/minus 0.6, 50.9 plus/minus 9.9), respectively. However, the time (min) to 25% T(1) recovery was significantly longer when monitored by the M-NMT (25.6 plus/minus 8) than by the MMG (20.2 plus/minus 6.3). During recovery from neuromuscular block, the difference between the TOF ratios measured by the two monitors showed a bias of -0.031, and the limits of agreement (bias plus/minus 1.96 SD) were -0.281 and +0.22. The M-NMT monitor could determine the time to tracheal intubation as well as full recovery from neuromuscular block, but it lagged behind the MMG in determining the time to rocuronium repeat dose administration. IMPLICATIONS: Compared with the Relaxometer mechanomyograph, the neuromuscular transmission module could equally indicate time to tracheal intubation and full recovery from 0.6 mg/kg rocuronium neuromuscular block. Its small quick-fit sensor has the advantage, in an often crowded and busy operating room, of being incorporated in the AS/3(TM) anesthesia workstation.

The effect of different stages of neuromuscular block on the bispectral index and the bispectral index-XP under remifentanil/propofol anesthesia.

Facial electromyographic activity and neuromuscular block could influence bispectral index (BIS) depth of anesthesia monitoring. In this study we examined, in 30 patients undergoing general surgical procedures, the effect of different stages of neuromuscular block on BIS monitoring and compared the conventional A-2000 BIS trade mark (BIS(3.4)) with the new BIS-XP trade mark (BIS(XP)). At deep surgical anesthesia BIS(3.4) of approximately 40, under a propofol 3.61 microg/mL target-controlled infusion and a 0.15-0.3 microg. kg(-1). min(-1) remifentanil infusion, mivacurium 0.15 mg/kg was administered. The onset of neuromuscular block triggered a brief transient odd divergence in response that manifested as a BIS(3.4) increase from 43 +/- 4 to 49 +/- 7 (P = 0.007) and a BIS(XP) decline from 41 +/- 3 to 35 +/- 3 (P = 0.003) at 1 +/- 0.2 min. Then, 2.5 +/- 1 min after mivacurium administration, both monitors returned to baseline values of 43 +/- 5 and 40 +/- 4, respectively. After that, BIS(3.4) and BIS(XP) did not significantly change during complete neuromuscular block or during various levels of neuromuscular recovery. At all phases, BIS(XP) was significantly lower than BIS(3.4). Our study indicated that the BIS(3.4)/BIS(XP) bias and the wide limits of agreement do not allow values given by the two monitors to be used interchangeably.