Summary

Background and objective: The time course of action of mivacurium does not correlate with its rapid breakdown by plasma cholinesterase. Pharmacokinetic–pharmacodynamic (PK–PD) modelling was applied to obtain more insight in the concentration–effect relationship.

Methods: Fourteen patients between 25 and 55 yr, undergoing non-major surgery, American Society of Anesthesiologists Grade I–II, were included. All patients received thiopentone/fentanyl/isoflurane/oxygen/nitrous oxide anaesthesia. Neuromuscular block was monitored mechanomyographically using single twitch stimulation (0.1 Hz). Mivacurium was administered as a short-term infusion, mean (standard deviation) duration 4.7 (1.0) min and dose 145 (33) μg kg−1. Arterial blood samples were obtained, and plasma was analysed using high performance liquid chromatography. PK–PD modelling was performed using an iterative Bayesian two-stage approach, assuming that the trans–trans and cis–trans isomers are equally potent.

Results: A PK–PD model with an effect compartment linked to plasma did not fit to the data satisfactorily. A model using an interstitial space compartment between plasma and effect compartment fitted significantly better. Parameters (mean (percentage coefficient of variation)) of the best fitting model were: kip 0.374 min−1 (46%), kei 0.151 min−1 (36%), EC50 98 μg L−1 (29%) and γ 3.7 (22%).

Conclusions: The PK–PD behaviour of mivacurium could be described using a model with an interstitial space compartment interposed between plasma and effect compartment. This model shows that the time course of mivacurium is mainly governed by the concentration decline in this interposed compartment and only indirectly related to the rapid plasma clearance.

Summary

Background and objective: To investigate and compare the performance of bispectral index (BIS) and auditory evoked response index (AAI) in detecting the transition from consciousness to unconsciousness during anaesthesia induction by propofol, alone and in combination with fentanyl.

Methods: Anaesthesia was induced with either an intravenous infusion of 30 mg kg−1 h−1 of propofol plus 2 μg kg−1 of fentanyl (Group PF, n = 20) or an intravenous infusion of 30 mg kg−1 h−1 of propofol plus normal saline (Group P, n = 20). BIS, AAI and the doses of propofol administered were recorded at the end-point of unresponsiveness to verbal commands. The propofol plasma concentration was also measured.

Results: The propofol dose and plasma propofol concentration required to achieve loss of consciousness were significantly lower in patients pretreated with fentanyl (P < 0.001). The mean BIS value at loss of consciousness was significantly different between the two groups (74.10 in Group PF vs. 60.80 in Group P) (P < 0.001). However, no difference in the AAI was seen between the two groups at loss of consciousness (32.90 in Group PF vs. 31.80 in Group P) (P > 0.05). In both groups, the regression analysis values (r-values) between BIS and plasma propofol concentrations at the onset of unconsciousness were higher than those between AAI and propofol concentrations (0.553 vs. 0.180 in Group P; 0.432 vs. 0.308 in Group PF).

Conclusions: These results show that a fentanyl bolus is effective in augmenting the hypnotic effect of propofol during anaesthesia induction. AAI appears to be able to measure the transition from consciousness to unconsciousness at similar values, regardless of whether or not fentanyl pretreatment is used whereas the BIS values were not independent of fentanyl pretreatment. This suggests that AAI may be a better indicator of conscious status during propofol/fentanyl anaesthesia, where it appears to be independent of the anaesthesia regimen.

Summary

Background and objective: This randomized, prospective study was performed to evaluate the efficacy of a subcutaneous local anaesthetic infiltration prior to venepuncture using different cannula sizes.

Methods: Three-hundred-and-one patients were included in the study, 150 received mepivacaine 1% (0.25 mL) subcutaneously, 151 were cannulated without local analgesia. Patients were further allocated to one of five cannula size groups (standard wire gauge (G)): 20-, 18-, 17-, 16- and 14-G. They were asked to quantify the pain experienced using a four-point rating scale.

Results: In the group without local anaesthetics, 28.8% complained about pain compared to 12% receiving local analgesia. The incidence of pain for 14-G (10%) and 16-G (12.9%) cannulae was significantly reduced in the local analgesia group (P < 0.01) compared to no local analgesia (77.4% and 45.1%). Other cannula sizes showed no difference in pain whether using local analgesia or not.

Conclusions: Patients profit from a subcutaneous infiltration with mepivacaine 1% prior to intravenous cathetherization only when cannulae of size ≥16-G are inserted.

Summary

Background and objective: The analgesic potency of non-steroidal anti-inflammatory drugs and acetaminophen are still being debated. We have assessed the relative analgesic effect of ibuprofen, acetaminophen or the combination of both after orthopaedic surgery.

Methods: Sixty-one ASA I patients, scheduled for an elective anterior cruciate ligament reconstruction under general anaesthesia were randomized, in a double blind fashion, into one of three groups. The ibuprofen group (n = 17) received ibuprofen 800 mg orally 1 h before operation and again at 6 and 12 h after the initial dose. The acetaminophen group (n = 20) received of acetaminophen 1 g orally at the same time intervals. The combination group (n = 24) received both ibuprofen 800 mg and acetaminophen 1 g. Surgery was performed under general anaesthesia with propofol and fentanyl for induction and maintenance with propofol and nitrous oxide in oxygen. The patients were monitored for 24 h thereafter, and the following variables were assessed: pain by visual analogue and verbal scales, need for rescue intravenous opioid analgesia (i.e. ketobemidone) and adverse events.

Results: The ibuprofen group and the combination group experienced significantly less pain during the first 6 h after surgery than the acetaminophen group using the visual analogue and the verbal scales. The acetaminophen group also had a significantly higher average consumption of opioids during the first 6 and 24 h. There were no significant differences between the ibuprofen group and the combination group in respect of experienced pain or consumption of rescue analgesia. The incidence of side-effects, postoperative haemoglobin concentration and renal function, judged by creatinine clearance, were identical between the groups.

Conclusion: Ibuprofen 800 mg thrice daily reduced pain to a greater degree than acetaminophen 1 g thrice daily, after anterior cruciate ligament reconstruction under general anaesthesia. The combination of acetaminophen and ibuprofen did not provide any superior analgesic effect.

Summary

Background and objective: This study was performed to determine the individual exposure of paediatric operating theatre personnel to sevoflurane and to evaluate the impact of inhalation induction and various airway approaches on exposure to airborne sevoflurane.

Methods: Mean individual environmental (workplace air) exposure to sevoflurane and a biomarker of exposure (urinary sevoflurane) were monitored in 36 subjects (10 anaesthetists, 10 surgeons, 12 nurses and 4 auxiliary personnel) working in two paediatric operating rooms.

Results: Environmental and urinary values were significantly greater in anaesthetists compared with other groups, with median values of 0.65 ppm (interquartile range 1.36; 95th percentile 4.36) for breathing zone sevoflurane and 2.1 μg L−1 urine (interquartile range 2.6; 95th percentile 7.6) for urinary sevoflurane. Anaesthetists exceeded the 2 ppm maximum allowed environmental concentration recommended by the National Institute for Occupational Safety and Health in 4 of 22 cases (18.1%). A positive correlation was found between the number of patients undergoing inhalational induction each day and mean values of breathing zone and urinary sevoflurane. An increase in the number of daily laryngeal mask insertions, or the use of rigid bronchoscopy, are statistically related to higher environmental and urinary values (P < 0.01 and <0.00001 for breathing zone sevoflurane, P < 0.05 and <0.01 for urinary sevoflurane, respectively).

Conclusions: Anaesthesia with sevoflurane can pose a hazard of chronic exposure with anaesthetists having the highest risk. Endotracheal intubation offers considerable protection against exposure. Routine anaesthesia using a standard facemask, a laryngeal mask or rigid bronchoscopy are risk factors for increased anaesthetic exposure.

Summary

Background and objective: An acute inflammatory response associated with cerebral ischaemia–reperfusion contributes to the development of brain injury. Aprotinin has potential, though unexplained, neuroprotective effects in patients undergoing cardiac surgery.

Methods: Human neutrophil CD11b/CD18, endothelial cell intercellular adhesion molecule-1 (ICAM-1) expression and endothelial interleukin (IL)-1β supernatant concentrations in response to in vitro hypoxia–reoxygenation was studied in the presence or absence of aprotinin (1600 KIU mL−1). Adhesion molecule expression was quantified using flow cytometry and IL-1β concentrations by enzyme-linked immunosorbent assay. Data were analysed using ANOVA and post hoc Student–Newman–Keuls test as appropriate.

Results: Exposure to 60-min hypoxia increased neutrophil CD11b expression compared to normoxia (170 ± 46% vs. 91 ± 27%, P = 0.001) (percent intensity of fluorescence compared to time 0) (n = 8). Hypoxia (60 min) produced greater upregulation of CD11b expression in controls compared to aprotinin-treated neutrophils [(170 ± 46 % vs. 129 ± 40%) (P = 0.04)] (n = 8). Hypoxia–reoxygenation increased endothelial cell ICAM-1 expression (155 ± 3.7 vs. 43 ± 21 mean channel fluorescence, P = 0.0003) and IL-1β supernatant concentrations compared to normoxia (3.4 ± 0.4 vs. 2.6 ± 0.2, P = 0.02) (n = 3). Hypoxia–reoxygenation produced greater upregulation of ICAM-1 expression [(155 ± 3.3 vs. 116 ± 0.7) (P = 0.001)] and IL-1β supernatant concentrations [(3.4 ± 0.3 vs. 2.6 ± 0.1) (P = 0.01)] in controls compared to aprotinin-treated endothelial cell preparation (n = 3).

Conclusions: Hypoxia–reoxygenation-induced upregulation of neutrophil CD11b, endothelial cell ICAM-1 expression and IL-1β concentrations is decreased by aprotinin at clinically relevant concentrations.

Summary

Background and objective: Our hypothesis was that stroke volume variation during mechanical ventilation of the lungs would allow accurate prediction and monitoring of changes in cardiac index in response to fluid loading in patients with severe sepsis.

Methods: This was a prospective clinical study in a university hospital. Ten mechanically ventilated patients with severe sepsis or septic shock were given fluid loading with 500 mL 10% hydroxyethylstarch 200/0.5 over 30 min. Before and after fluid loading pulmonary arterial occlusion pressure and central venous pressure were measured. Intrathoracic blood volume index, stroke volume variation and cardiac index were measured by the transpulmonary thermodilution technique. After verifying normal distribution of the data (skewness <1.0) the paired t-test was used for statistical analysis.

Results: After fluid loading stroke volume variation decreased significantly, whereas central venous pressure, pulmonary arterial occlusion pressure, intrathoracic blood volume index and cardiac index increased significantly. Changes of cardiac index in response to fluid loading were correlated to baseline values of stroke volume variation (r = 0.64, P = 0.02) and intrathoracic blood volume index (r = −0.73, P = 0.009). Changes in cardiac index were significantly correlated to percentage changes in stroke volume variation (r = −0.65, P < 0.001) and changes in intrathoracic blood volume index (r = 0.52, P = 0.002), whereas changes in cardiac index revealed no significant correlation to changes in central venous pressure (r = 0.28, P = 0.07) and changes in pulmonary arterial occlusion pressure (r = 0.29, P = 0.06).

Conclusions: Measuring stroke volume variation may be a useful way of guiding fluid therapy in ventilated patients with severe sepsis because it allows estimation of preload and prediction of cardiac index changes in response to fluid loading.

Summary

Background and objectives: The American Heart Association guidelines from 2000 recommend that family members be allowed to witness cardiopulmonary resuscitation. This is controversial and opponents fear litigation and family interference during family witnessed resuscitation (FWR). The extent of FWR in UK Emergency Departments is unknown.

Methods: A telephone survey of a selection of UK Emergency Departments was performed asking about experience with FWR.

Results: One-hundred-and-sixty-two UK Emergency Departments with an average attendance of 47 000 patients per year participated. FWR was allowed by 128 (79%) for an adult patient and 93% for a child. Of these, 50% invited relatives to witness and only 21% did not permit FWR. The perceived benefits were: accepting that all possible has been done (48%), accepting the death (48%) and help with grieving (38%). Two percent did not think FWR was of help. Few had encountered any problems or interference from the family. Never being asked was the commonest reason not allowing FWR followed by staff reluctance. Most respondents would wish to be present if their child (85%), spouse/partner (64%) or elderly relative (52%) was being resuscitated.

Conclusions: FWR is common in UK Emergency Departments. It is more common when children are being resuscitated than adults. Further research is needed to demonstrate whether it is of benefit to the patient or relatives and its applicability to other areas such as intensive care.

Summary

Background and objective: To evaluate the temporal changes in respiratory physiological dead space and dynamic compliance of the respiratory system during non-abdominal, upper abdominal and lower abdominal surgery under general anaesthesia with intermittent positive pressure ventilation.

Methods: Thirty-four adult patients were studied (non-abdominal surgery, n = 8; upper abdominal surgery, n = 13 and lower abdominal surgery in lithotomy position, n = 13). Physiological dead space was measured using the single breath carbon dioxide test. The physiological dead space to tidal volume ratio (VD/VT), dynamic compliance of respiratory system, expiratory tidal volume and respiratory rate were measured 10 min after tracheal intubation, and 30, 60 and 120 min later.

Results: In lower abdominal surgery group, VD/VT was significantly increased at 120 min compared with 0 min (P = 0.005) and 30 min (P = 0.009). There were no significant differences in VD/VT between the three groups at any time point. Compliance decreased significantly in patients with upper abdominal (120 min) and lower abdominal surgery (60 and 120 min), but there were no significant changes during non-abdominal surgery.

Conclusions: We found that the VD/VT increased in patients undergoing lower abdominal surgery in lithotomy and head down tilt, and compliance decreased in those undergoing upper abdominal and lower abdominal surgery over time.

Summary

Background and objective: To compare the perioperative effects of melatonin and midazolam given in premedication, on sedation, orientation, anxiety scores and psychomotor performance.

Methods: Exogenous administration of melatonin not only facilitates the onset of sleep but also improves its quality. A prospective, randomized, double-blind, placebo-controlled study was performed in 66 patients undergoing laparoscopic cholecystectomy. Patients were given melatonin 5 mg, midazolam 15 mg or placebo, 90 min before anaesthesia, sublingually. Sedation, orientation and anxiety were quantified before; 10, 30, 60 and 90 min after premedication; and 15, 30, 60 and 90 min after admission to the recovery room. Neurocognitive performance was evaluated at these times, using the Trail Making A and B and Word Fluency tests. The differences between the groups were analysed by ANOVA. Two-way comparisons were performed by Scheffé analysis. Sedation and amnesia were analysed by the χ2 test.

Results: Patients who received premedication with either melatonin or midazolam had a significant increase in sedation and decrease in anxiety before operation compared with controls. After operation, there was no difference in sedation scores of all groups. Whereas, 30, 60 and 90 min after premedication the melatonin and midazolam groups exhibited a significantly poorer performance in Trail Making A and B tests compared with placebo, there were no significant differences among the groups in terms of neuropsychological performance after the operation. Amnesia was notable only in the midazolam group for one preoperative event.

Conclusion: Melatonin premedication was associated with preoperative anxiolysis and sedation without postoperative impairment of psychomotor performance.

Summary

Background and objective: We tested the hypothesis that disturbances of the visual pathway following sevoflurane general anaesthesia (a) exist and persist even after clinical discharge criteria have been met and (b) are associated with decreased contrast sensitivity.

Methods: We performed pattern and full-field flash electroretinograms (ERG) in 10 unpremedicated ASA I patients who underwent nitrous oxide/sevoflurane anaesthesia. ERG and contrast sensitivity were recorded preoperatively, immediately after discharge from the recovery room and 2 h after discontinuation of sevoflurane. The time at which the Post Anaesthesia Discharge Score first exceeded 9 was also noted. Data were analysed using paired, one-tailed t-tests and Pearson's correlation coefficient.

Results: On the full-field photopic ERG, b-wave latency was greater at each postoperative time point (31.6 ± 1.1 and 30.8 ± 1.1 ms) compared to preoperatively (30.1 ± 1.1 ms, P < 0.001 and P = 0.03, respectively). Oscillatory potential latencies were greater on discharge from the recovery room compared with pre-anaesthetic values (23.1 ± 3.1 vs. 22.4 ± 3.3 ms, P = 0.01) and returned to baseline by 2 h after emergence from anaesthesia. Also at 2 h after emergence from anaesthesia: (a) P50 latency on the pattern ERG was greater than at baseline (81.5 ± 17.9 vs. 51.15 ± 22.6 ms, P = 0.004); (b) N95 amplitude was less compared to pre-anaesthetic values (2.6 ± 0.5 vs. 3.3 ± 0.4 μV, P = 0.003) and (c) contrast sensitivity was less compared to baseline values (349 ± 153 vs. 404 ± 140, P = 0.048). A positive correlation was demonstrated between contrast sensitivity and both N95 amplitude and b-wave latency (r = 0.99 and r = −0.55 at significance levels of P < 0.005 and P < 0.05, respectively).

Conclusions: Postoperative ERG abnormalities and associated decreases in contrast sensitivity are consistently present in patients who have undergone nitrous oxide/sevoflurane anaesthesia. These abnormalities persist beyond the time at which standard clinical discharge criteria have been met.

Summary

Background and objective: This study was undertaken to investigate the role played by antidiuretic hormone (ADH), the renin–angiotensin system and atrial natriuretic factor (ANF) in the oliguria in patients undergoing spinal fusion.

Methods: Sixteen patients undergoing posterior spinal fusion using isoflurane and fentanyl (n = 8) or sufentanil (n = 8) had renin, aldosterone, ADH and ANF measurements.

Results: Compared to the non-oliguric patients, the oliguric patients had a higher number of fused vertebrae 10.5 ± 1.3 vs. 9.0 ± 0.5 (P = 0.01) and higher renin values at 12 h (3.3 ± 3.2 vs. 0.7 ± 0.6 ng L−1 s−1, P = 0.04). Hormonal values that had a significant correlation with intraoperative diuresis were: renin at 0.5 h (r2 = 0.26, P = 0.04), aldosterone at 0.5 h (r2 = 0.30, P = 0.03) and ANF at 0.5 h (r2 = 0.32, P = 0.02). Those that had a significant correlation with the mean postoperative diuresis were: renin at 6 h (r2 = 0.29, P = 0.03), 8 h (r2 = 0.26, P = 0.04) and 12 h (r2 = 0.31, P = 0.03), aldosterone at 6 h (r2 = 0.54, P = 0.001), 8 h (r2 = 0.40, P = 0.01) and 12 h (r2 = 0.32, P = 0.03), ADH at 24 h (r2 = 0.38, P = 0.01) and ANF at 6 h (r2 = 0.26, P = 0.045). Using stepwise regression, excluding hormonal values, only two continuous variables had a significant correlation with the mean postoperative diuresis: the number of fused vertebrae (P = 0.02) and the length of surgery (P = 0.02).

Conclusion: Activation of the renin–angiotensin system is the major cause of the early intraoperative oliguria. ADH and the renin–angiotensin system are both involved in the pathophysiology of postoperative oliguria in patients undergoing spinal fusion.

Summary

Background and objective: This study was designed to determine which single bolus dose of remifentanil in combination with propofol and nitrous oxide is best to control the haemodynamic, autonomous and somatic responses in patients scheduled for dilatation and curettage of the uterine cervix. We evaluated the adequacy of different bolus doses of remifentanil, associated with propofol and nitrous oxide, for dilatation and curettage in a prospective double-blind study.

Methods: After institutional approval and informed consent, 34 healthy females undergoing curettage to remove material from the uterus after spontaneous abortion were randomized to receive remifentanil 0.5 μg kg−1 intravenously (i.v.) (Group A; n = 4), 1 μg kg−1 i.v. (Group B; n = 15) or 1.5 μg kg−1 i.v. (Group C; n = 15), with propofol 2 mg kg−1 i.v. in all groups. Anaesthesia was maintained with 60% nitrous oxide in oxygen. Haemodynamic, somatic and autonomic signs of light anaesthesia were registered to assess the response to surgical stress. Recovery times and Aldrete score were recorded at the end of the procedure.

Results: The groups were similar with regard to biometric data and duration of surgery. The poor results using the lowest dose of remifentanil obliged us to abandon this dose. The total dose of remifentanil was larger in Group C (100 ± 5.7 μg vs. 65 ± 4.1 μg in Group B; P < 0.05), but more patients required extra bolus injections in Group B (69% vs. 38% in Group C; P < 0.01). Recovery times were significantly shorter in Group C. Aldrete scores when leaving the operation room was similar.

Conclusions: Remifentanil 1.5 μg kg−1 i.v. with propofol 2 mg kg−1 i.v. and 60% nitrous oxide in oxygen provided the best anaesthetic control with the fastest recovery times.

Summary

Background and objective: Platelet function abnormalities influence the haemostatic defect in patients with liver failure. Patients after orthotopic liver transplantation present thrombocytopaenia associated with bleeding problems, which may be aggravated by the interaction of hydroxyethyl starches with platelets.

Methods: From 12 patients after liver transplantation venous blood samples (3 mL) were taken before, 20 and 120 min after infusion of hydroxyethyl starch of medium molecular weight (200 kDa/0.5) 6% 10 mL kg−1 over a period of 30 min. Surface expression of glycoprotein IIb/IIIa and P-selectin were quantified by flow cytometry as well as the percentage of platelet–leucocyte complexes.

Results: A significant decrease of P-selectin expression following administration of hydroxyethyl starch after 120 min (89.1 ± 4.2%, P = 0.029) and a corresponding significant reduction in the formation of platelet– monocyte complexes (81.1 ± 7.8%, P = 0.001) were observed. There was no alteration in the glycoprotein IIb/IIIa expression after hydroxyethyl starch infusion.

Conclusions: Infusion of hydroxyethyl starch 200 kDa/0.5 in clinically relevant doses does not alter glycoprotein IIb/IIIa expression in thrombocytopaenic patients with pre-existing platelet dysfunction after orthotopic liver transplantation. Accordingly, infusion of hydroxyethyl starch may have a beneficial effect on microvascular graft perfusion through the resulting haemodilution and reduced P-selectin expression with subsequent reduced leucocyte–platelet complexes and endothelial adhesion.

Summary

Background and objective: For use in a magnetic resonance (MR) scanning room infusion pumps must be MR safe and compatible. This study tested two commonly used infusion pumps (Alaris P6000 and Alaris Asena-GH) to determine if they met these criteria.

Methods: The pumps underwent testing within the scanning room of a 3 T MR scanner. Pump infusion rates were tested at up to 100 Gauss magnetic field strength, with and without radio frequency signals present. The effect of the pumps on image quality was assessed. The occlusion pressure alarm of the pumps was tested at up to 100 Gauss. The projectile risk was assessed by measuring the force exerted upon the pumps at the entrance to the scanner.

Results: The maximum mean flow rate errors at 100 Gauss were 2.18% for the Alaris P6000 and 1.42% for the Alaris Asena-GH, both within our accepted limits. Radio frequency signals had no effect on flow rate. The pumps produced no discernable artefacts on the acquired images. The maximum mean occlusion pressure error was 204 mmHg higher for the Alaris P6000 pump and 99 mmHg lower for the Alaris Asena-GH (P-values < 0.001) at 100 Gauss compared to testing outside the scanner. Both pumps were subject to significant attractive force at the entrance to the scanner.

Conclusions: Whilst the pumps cannot strictly be termed MR safe or compatible at 100 Gauss we have demonstrated that flow rates are unchanged and that, for the Alaris Asena-GH, the effect on the occlusion pressure alarm is unlikely to have patient safety implications.

Summary

Background and objective: This randomized, double-blinded, prospective study compared the effects of clonidine, esmolol or alfentanil on the level of hypnosis and haemodynamic responses to intravenous induction of anaesthesia and endotracheal intubation.

Methods: Forty-five patients scheduled for elective surgery were allotted to one of three groups. They were given either alfentanil 3 μg kg−1min−1 (n = 15); esmolol 1 mg kg−1min−1 (n = 16) or clonidine 3 μg kg−1 (n = 14) as a 10 min infusion. The infusions of alfentanil and esmolol, but not of clonidine, were maintained during endotracheal intubation. Anaesthesia was induced with midazolam (2 mg) and thiopental as required to suppress the eyelash reflex. Atracurium (0.5 mg kg−1) was given to produce neuromuscular block. Mean arterial pressure, heart rate, and bispectral index were recorded on arrival (baseline), after study drug infusion, after injecting midazolam and thiopental, as well as after endotracheal intubation. ANOVA and χ2-test were used for analysis.

Results: Blood pressure, heart rate and the bispectral index were unaltered by the study drugs, but thiopental requirements were reduced by alfentanil and clonidine (P < 0.014). Mean arterial pressure values (mean ± standard error of mean) in the alfentanil, esmolol and clonidine groups were: baseline: 107.8 ± 3.8; 106.6 ± 3.9; 103.4 ± 3.7 mmHg; after thiopental: 74.0 ± 4.2; 85.6 ± 4.3; 94.2 ± 4.1 mmHg and after endotracheal intubation: 91.7 ± 5.3; 114.1 ± 6.9; 123.6 ± 5.6 mmHg, respectively (two-way ANOVA, P < 0.001). Mean arterial pressure changed significantly after intubation from baseline (P < 0.001) after alfentanil (− 15%) and clonidine (+ 20%) but not after esmolol (+ 7%), while the changes between pre- and postintubation values were similar in all groups (24–33% increase). The bispectral index indicated that all patients had an adequate level of hypnosis, but the variability was higher in the esmolol group (P < 0.002).

Conclusions: None of the study drugs blocked the increase in mean arterial pressure induced by endotracheal intubation, but esmolol provided better overall haemodynamic stability. All groups had an adequate level of hypnosis.

Summary

Background and objective: To compare the antiemetic efficacy of ondansetron with two different hypnotic drugs (propofol 15 mg, midazolam 1 and 2 mg) for the treatment of established postoperative nausea and vomiting (PONV).

Methods: Four-hundred-and-fifty-three patients scheduled for elective gynaecological or abdominal surgery were enrolled. One-hundred-and-twenty patients (26%) experienced postoperative emesis, and when nausea scores reached 2 or greater on a five-point scale, they were randomized to receive intravenously: propofol 15 mg (1.5 mL) in Group P, midazolam 1 mg in Group M1, midazolam 2 mg in Group M2 and ondansetron 4 mg in Group O.

Results: Four patients (13.3%) in Group P, 13 patients (43.3%) in Group M1, five patients (16.6%) in Group M2 and one patient (3.3%) in Group O required a second dose of the study drug. After administration of the study drugs, nausea scores were significantly lower in all groups than before these drugs were given. No patient had a sedation score over 3 (the patients remained awake and/or responded to verbal contact). The sedative effects of midazolam and propofol lasted for a much shorter time than the antiemetic effects of these drugs.

Conclusions: Propofol and midazolam used in subhypnotic doses were as effective as ondansetron in treating PONV in patients undergoing abdominal or gynaecological surgery without untoward sedative or cardiovascular effects.

Summary

Background and objective: Xenon reduces the infarct size after regional ischaemia in the rabbit heart in vivo, but the underlying mechanisms are unknown. Since adhesion molecules on neutrophils are closely involved in the pathophysiology of ischaemia/reperfusion injury and modulation of neutrophil function, we investigated the effect of xenon on neutrophil adhesion molecule expression in vitro.

Methods: Freshly isolated neutrophils were incubated with 30% or 60% xenon for 60 min. In unstimulated and after stimulation with either N-formyl-methionyl-leucyl-phenylalanine or phorbol-12-myristate-13-acetate neutrophil surface expression of PSGL-1, L-selectin, CD11a and CD11b were measured by flow cytometry.

Results: At both concentrations, xenon reduced the surface expression of PSGL-1 by 10% (P < 0.05), and of L-selectin by 15% (P < 0.05) in the 60% xenon group. Furthermore, N-formyl-methionyl-leucyl-phenylalanine activated neutrophils showed an increased removal of L-selectin from the neutrophil surface following incubation with xenon (30% compared to controls, P < 0.05). Neutrophil β2-integrin expression was not altered by xenon.

Conclusions: Xenon increases the removal of the selectins PSGL-1 and L-selectin from the neutrophil surface in vitro. Since both selectins are involved in the initial contact between neutrophils and endothelial cells, xenon may affect neutrophil adhesion to endothelium during ischaemia/reperfusion injury. However, because the β2-integrin expression was unaffected by xenon, further investigations are required to clarify whether xenon may modulate neutrophil transmigration through endothelial cells in vivo.

Summary

Background and objective: To examine the calibration of the prognostic system Acute Physiology and Chronic Health Evaluation Score (APACHE II) regarding hospital mortality and predicting weaning outcome after long-term mechanical ventilation of the lungs.

Methods: Prospective observational cohort study performed in a respiratory intensive care unit including 246 patients whose lungs were ventilated for 42.1 ± 37.8 (median 30) days in the referring hospital. APACHE II (24 h after admission to our respiratory intensive care unit) and the cause of respiratory failure, underlying disease, prior duration of mechanical ventilation and gender were recorded. The predictive power was evaluated with sensitivity and specificity for different cut-off points and summarized in a receiver operating characteristic curve.

Results: No difference was found between survivors (APACHE II 16.0 ± 4.3) and non-survivors (APACHE II 16.9 ± 5.1). In a mean time of 8.0 ± 10.3 days, 146 patients (59.3%) were successfully weaned (APACHE II 15.2 ± 3.5). One-hundred patients (40.7%) were considered unweanable (APACHE II 17.7 ± 5.3). Recalibration of APACHE II to predict weaning failure was possible, resulting in an area under the receiver operating characteristic curve (AUC) of 0.638. Furthermore the AUC improved to 0.723 by changing the weights of selected APACHE items and introducing external factors. Diagnostic accuracy fell from group with mechanical ventilation ≤25 days (AUC 0.770) to group with mechanical ventilation >50 days (AUC 0.517).

Conclusions: APACHE II did not predict hospital mortality after long-term mechanical ventilation of the lungs. Not the original APACHE II but a recalibrated and adapted APACHE II can be useful to predict weaning outcome in patients with less than 25 days of prior lung ventilation.