bluuebunny/crossref_metadata_2025 huggingface dataset:
Decisions not to resuscitate in a Swedish university hospital
Authors: FRIBERG H. , ADOLFSSON A. , LUNDBERG D.
Published: January 2009

Background: Cardiopulmonary resuscitation (CPR) has the potential to save many lives. Used indiscriminately though, it may be harmful and not in the best interest of the patient. An advance directive to refrain from resuscitation in selected patients is probably not uncommon in Sweden, but guidelines ruling this are still generally lacking. This study was performed to evaluate the use and documentation of do–not–resuscitate orders in a Swedish university hospital.

Methods: Adult inpatients at 7 medical, 3 surgical and 2 neurological wards, a total of 220, were investigated on one specific day by interviewing the physicians and nurses responsible for their care.

Results: We found a discrepancy in doctors' and nurses' perception concerning the appropriateness of CPR in selected patients. CPR was judged by doctors to be inappropriate for 45 patients (20%). Out of these 45 patients, only 24 had a written do–not resuscitate order in their medical record, in most cases noted as a code word or sign only. Rarely were the patient or his/her relatives involved in the decision–making process.

Conclusion: We conclude that a decision to refrain from resuscitation is often not made, even when considered medically and ethically justifiable. Also, the use of coded information as a sole indicator for a patient not to be resuscitated is still common practice. The patient or his/her relatives are rarely involved in this decision.
Serum protein binding of propofol in critically ill patients
Authors: ZAMACONA M. K. , SUÁREZ E. , AGUILERA L. , RODRÍGUEZ–SASIAÍN J. M. , AGUIRRE C. , CALVO R.
Published: January 2009

Background: Disease‐induced modifications in the level of serum proteins may change the degree of binding of drugs highly bound to serum proteins.

Methods: The serum protein binding of propofol, an intravenous anaesthetic agent, was studiedin vitroin samples of serum from healthy volunteers (n = 28) and from critically ill patients (n = 17). The free fraction was obtained by the ultrafiltration technique and was measured by high‐performance liquid chromatography. Concentrations of serum albumin, α1acid‐glycoprotein and free fatty acids were also measured in all samples.

Results: The percentage of free propofol was significantly increased (P< 0.001) in critically ill patients (1.31 (1.06–2.25)%) vs control subjects (1.07 (0.49–1.47)%). Albumin levels were significantly decreased (P<0.001) in patients (16.3 (8.8–24.6) g–1‐1vs 45.8 (31.4–55.5) g–1“1), while levels of α1‐acid‐glycoprotein were increased (P<0.001) (1.9 (0.9–2.8) g l‐1vs 0.9 (0.5–1.4) g 1‐1), as were levels of free fatty acids (0.68 (0.50–1.14) mmol I‐1vs 0.37 (0.11–1.05) mmol I‐1;P< 0.05). No correlation was found between levels of α1–acid–glycoprotein or free fatty acids and the bound/free ratio of propofol. However, a linear relationship was found between levels of albumin and the bound/free ratio (r2=O.25;P< 0.001).

Conclusion: In conclusion, in these critically ill patients, an increase in the percentage of free propofol occurs. The significance of this observation remains uncertain, but may be validated in future studies. However, the observation supports the common idea that potent drugs should be given with great care in critically ill patients.
Comparison of ondansetron and droperidol in the prevention of postoperative nausea and vomiting after laparoscopic surgery in women
Authors: KOIVURANTA M. , LÄÄRÄ E. , RANTA P. , RAVASKA P. , ALAHUHTA S.
Published: January 2009

Background: Women undergoing laparoscopic surgery are susceptible to postoperative nausea and vomiting (PONV). Ondansetron and droperidol are useful antiemetics. This study was designed to ascertain primarily the relative difference in efficacy of ondansetron and droperidol and secondarily between these drugs and placebo in the prevention of PONV after laparoscopic surgery.

Methods: The prophylactic antiemetic efficacy of ondansetron and droperidol was compared in a prospective, randomised, double–blind, placebo–controlled trial of 439 female inpatients scheduled for laparoscopic surgery. During induction of standardised general anaesthesia the patients received intravenously either ondansetron 8 mg (n=195), droperidol 1.25 mg (n=193) or placebo (n=51). The occurrence of nausea, vomiting, sideeffects and the need for rescue antiemetic medication were recorded for 24 h postoperatively.

Results: The proportion of patients with nausea was 48%, 50% and 67% in the ondansetron, droperidol and placebo groups, respectively; with a significant difference when both ondansetron (P=0.02) and droperidol (P=0.04) were compared with placebo. Vomiting occurred in 18%, 26% and 37% of the patients in the three groups, respectively (P=0.05 between ondansetron and droperidol, P=0.004 between ondansetron and placebo, P=0.16 between droperidol and placebo). The proportion of patients given rescue medication was 34%, 28% and 49%, respectively (P=0.23 for ondansetron and droperidol, P=0.07 for ondansetron and placebo, P=0.007 for droperidol and placebo). During early recovery the patients treated with ondansetron were significantly more alert than after droperidol. Serious side–effects were not observed. Headache was significantly more common after ondansetron than after droperidol treatment.

Conclusions: The efficacy of prophylactic ondansetron and droperidol in reducing postoperative nausea associated with laparoscopic surgery in female inpatients was similar, but ondansetron appeared to be slightly more efficient than droperidol in preventing vomiting. Ondansetron and droperidol were both significantly better than placebo in the prophylaxis of PONV.
Treatment of ventricular fibrillation during anaesthesia in an anaesthesia simulator
Authors: LINDEKÆR A. L. , JACOBSEN J. , ANDERSEN G. , LAUB M. , JENSEN P. F.
Published: January 2009

Background: To evaluate treatment of ventricular fibrillation (VF) occurring during anaesthesia and the use of a full–scale simulator, 80 anaesthetists in teams of two were attending a training session in the simulator Sophus.

Methods: The sessions were recorded on videotape and reviewed with the anaesthetists afterwards. Time of treatment and the sequence were registered.

Results: Onset time for VF was the starting point. Most of the subjects changed respiratory settings. Four teams did not change inspiratory oxygen and 17 teams did not turn off the vaporiser. Cardiac compression was initiated by all teams. DCdefibrillation was not used by two teams, with 38 of 40 teams defibrillating once, 37 twice and 29 teams three times. Adrenaline was administered by 30 of 40 teams.

Conclusion: There was very little consistency among the teams regarding treatment for VF according to accepted algorithms. An anaesthesia simulator could be a tool for training and it is a safe way of demonstrating for the anaesthetist that certain treatment algorithms and behaviour during critical incidents are the most effective.
Should nitrous oxide be discontinued before desflurane after anaesthesia with desflurane/N2O?
Authors: EINARSSON S. , CERNE A. , BENGTSSON A. , STENQVIST O. , BENGTSON J. P.
Published: January 2009

Background: The appearance of hypoxaemia immediately after anaesthesia with nitrous oxide may be partially explained by diffusion hypoxia. This study was undertaken to evaluate circulatory and respiratory variables during emergence after desflurane/nitrous oxide anaesthesia, and whether there are any differences depending on which gas is discontinued first.

Methods: 20 patients were studied after gynaecological laparoscopic surgery. The depth of anaesthesia was reduced 10 min prior to the emergence by stopping the administration of one of the two inhalational agents. Desflurane was discontinued first in Group 1, nitrous oxide in Group 2. Ventilation was controlled with E'C02 maintained at 5% until the administration of the second anaesthetic gas was discontinued. Thereafter, the patients breathed spontaneously.

Results: The PaC02 at which the respiratory drive reappeared after controlled normoventilation was similar in both groups, 6.1–6.5 kPa, and extubation was performed after 10–11 min. At extubarion, the end–tidal C02 and total MAC were similar in the groups, about 6.2 vol% and 0.16, respectively. Mean arterial blood pressure was significantly higher in Group 1. The cardiac output increased in both groups from about 6 1/min at the conclusion of anaesthesia to 9.0 and 7.6 1/min at 15 min in the recovery period. End–tidal O2 decreased and CO2 increased in both groups during the first 10 min in the recovery period. pH was reduced at 15 and 30 min in both groups.

Conclusion: Irrespective of which agent was discontinued first, there was an increase in cardiac output, decrease in oxygenation and a modest acidosis in the first 30–min recovery period. The only significant difference between the groups was in mean arterial blood pressure in the early emergence phase with a greater MAP when N2O had been used until the conclusion of anaesthesia.
Emergence from isoflurane/N2O or isoflurane anaesthesia
Authors: EINARSSON S. , BENGTSSON A. , STENQVIST O. , BENGTSON J. P.
Published: January 2009

Background: The first goal of anaesthetic recovery is return of the patient's ability to independently maintain respiratory and circulatory functions. Nitrous oxide remains popular due to minor effects on the cardiovascular and respiratory systems. However, diffusion hypoxaemia can occur during recovery and there is a potential advantage of providing the patient with only a potent vaporised agent.

Results:Patients anaesthetised with isoflurane/N2O resumed their spontaneous breathing 16 min earlier and were extubated 22 min earlier than those anaesthetised with only isoflurane. At extubation, total MAC and end–tidal CO2 were similar in both groups, 0.22–0.26 and 5.5–5.9 vol%, respectively. The isoflurane/N2O group had greater minute ventilation and CO2 excretion rates than the isoflurane group throughout the emergence period. There were no significant differences between the groups in blood gas variables or in heart rate, mean arterial blood pressure or cardiac index. Cardiac index was between 3.4 and 3.9 1 m‐2 min‐1 throughout the emergence period in both groups.

Conclusion:Patients anaesthetised with only isoflurane had a longer delay until resumption of spontaneous breathing and extubation in the emergence period. Minute ventilation and carbon dioxide elimination were also significantly more suppressed throughout emergence after anaesthesia with isoflurane as compared with isoflurane/N2O.

Methods: This randomised study of 20 gynaecological patients evaluated respiratory and circulatory variables during emergence after anaesthesia with equipotent mixtures of isoflurane/ nitrous oxide or isoflurane. Inspired, end–tidal and mixed expired gas concentrations, expired minute volume, pulse oximetry saturation and arterial blood gases were registered. Monitoring of cardiac output was performed by transthoracic bioimpedance.
Influence of anaesthesia and muscle relaxation on intubating conditions and sympathoadrenal response to tracheal intubation
Authors: SPARR H. J. , LEO C. , LADNER E. , DEUSCH E. , BAUMGARTNER H.
Published: January 2009

Background: The study aimed to assess the relative influence of anaesthesia and muscle relaxation on intubating conditions and the haemodynamic and catecholamine responses to tracheal intubation.

Methods: Sixty ASA 1 or 2 patients were randomly assigned to one of four groups (15 patients each) that differed in the depth of anaesthesia (thiopentone plus fentanyl 2.5 μg kg‐1 or thiopentone alone) and the degree of vecuronium–induced neuromuscular block (100% or _>: 65%) at intubation. Muscle relaxation was measured at 0.1 Hz by means of mechanomyography. Heart rate (HR) and mean arterial blood pressure (MAP) were measured before and after induction of anaesthesia, and 1 min and 5 min following intubation, while adrenaline (A) and noradrenaline concentrations (NA) were determined from arterial blood samples.

Results: Intubating conditions were improved primarily by providing complete muscle relaxation at the adductor pollicis muscle (P<0.001) and to a lesser extent by adding fentanyl to thiopentone (P=0.04). The response of HR and MAP to tracheal intubation was attenuated mainly by fentanyl (P<0.001). Complete muscle relaxation further diminished the response of MAP to intubation (P=0.03). Changes in A and NA were dependent on the depth of anaesthesia only (P =>0.01).

Conclusion: The results of the study demonstrate that the sympathoadrenal response to intubation is attenuated by adding fentanyl (2.5 kg‐1) to an induction regimen with thiopentone, whereas provision of complete muscle relaxation at the adductor pollicis muscle is necessary to attain smooth intubating conditions.
Atracurium–induced neuromuscular block is not affected by chronic anticonvulsant therapy with carbamazepine
Authors: SPACER A. , NEIGER F. X. , SPISS C. K. , KRESS H. G.
Published: January 2009

Background: Patients on chronic anticonvulsant therapy are relatively resistant to some nondepolarizing neuromuscular blockers. Because of the controversial reports on atracurium, the purpose of the present study was to determine the effect of longterm carbamazepine treatment on the neuromuscular block produced by this muscle relaxant.

Methods: Eighteen otherwise healthy individuals scheduled for neurosurgical interventions were studied. Eight patients had received carbamazepine for an average of 41 weeks (range 4–156 weeks) prior to surgery. Ten patients without carbamazepine exposure served as controls. After premedication with oral diazepam, anaesthesia was induced with fentanyl and thiopental and maintained with nitrous oxide and isoflurane in oxygen. Atracurium was given for neuromuscular blockade and the evoked electromyogram (EMG) was recorded with a Datex Monitor NMT.

Results: The lag time, the onset time, the duration 10%, 25%, 50%, 75% and the interval 25–75% did not differ between the groups.

Conclusion: Our results with atracurium differ from previous data demonstrating an influence of carbamazepine therapy on the pharmacokinetics and/or pharmacodynamics of other nondepolarizing muscle relaxants. As documented in this study, atracurium produces adequate neuromuscular block in patients chronically exposed to carbamazepine. Chronic carbamazepine therapy does not influence the onset time and duration of action of atracurium–induced neuromuscular block.
Attenuation of serotonin–induced contractures in skeletal muscle from malignant hyperthermia–susceptible patients with dantrolene
Authors: WAPPLER F. , SCHOLZ J. , RlCHTHOFEN V. VON , FlEGE M. , KÖCHLING A. , LAMBRECHT W. , ESCH J. SCHULTE AM
Published: January 2009

Background: Porcine malignant hyperthermia (MH) can be triggered by administration of certain serotonin2receptor agonists. Pretreatment with dantrolene completely abolished serotonininduced MH. The purpose of this study was to investigate the effects of the serotonin2receptor agonist l–(2,5–dimethoxy–4–iodophenyl)–2–aminopropane (DOI) in skeletal muscle specimens from MH–susceptible (MHS) and MH–nonsusceptible (MHN) patients following pretreatment with dantrolene.

Results: Administration of DOI 0.02 mM induced contractures in muscle specimens from MHS and MHN patients. Contracture development started significantly earlier in MHS than in MHN specimens. In MHS muscle the maximum contracture was significantly greater than in MHN. Pretreatment with dantrolene significantly delayed the start of contracture development in MHS muscles, whereas in MHN muscles no contractures were observed after dantrolene. The contracture maximum was significantly reduced in MHS.

Conclusion: The acceleration of DOI–induced contracture development in skeletal muscle specimens from MHS patients indicates that an altered serotonin system might be involved in human MH. Dantrolene effectively delayed serotonin–induced contractures. Further investigations are needed to determine whether serotonin2receptors of skeletal muscle from MHS subjects are altered in function or structure, or whether this response is a secondary phenomenon.

Method: We used muscle specimens surplus to diagnostic requirements from 12 MHS and 13 MHN patients in this study. In the first experiment, DOI 0.02 mM was added to the organ bath. In the second experiment, muscle specimens were preincubated with dantrolene 0.5 μM or 1.0 nM, respectively, for 10 min before DOI 0.02 mM was administered.
Effects of cisatracurium on cerebral and cardiovascular hemodynamics in patients with severe brain injury
Authors: SCHRAMM W. M. , JESENKO R. , BARTUNEK A. , GILLY H.
Published: January 2009

Background: For neuroanesthesia and neurocritical care the use of drugs that do not increase or preferentially decrease intracranial pressure (ICP) or change cerebral perfusion pressure (CPP) and cerebral blood flow (CBF) are preferred. The current study investigates the effects of a single rapid bolus dose of cisatracurium on cerebral blood flow velocity, ICP, CPP, mean arterial pressure (MAP) and heart rate (HR) in 24 mechanically ventilated patients with intracranial hypertension after severe brain trauma (Glasgow coma scale 6) under continuous sedation with sufentanil and midazolam.

Methods: Patients were randomly assigned to receive either 2XED95 (n=12) or 4XED95 (n=12) of cisatracurium as a rapid i.v. bolus injection. Before and after bolus administration mean cerebral blood flow velocity (BFV, cm/s) was measured in the middle cerebral artery using a 2–MHz transcranial Doppler sonography system, ICP (mm Hg) was measured using an extradural probe, and MAP (mm Hg) and HR (b/min) were measured during a study period of 20 min. Cerebral perfusion pressure (CPP=MAP–ICP) was also calculated.

Results: Our data show that a single bolus dose of up to 4 × ED95 cisatracurium caused no significant (P<0.05) changes in BFV, ICP, CPP, MAP and HR. Possible histamine‐related events were not observed during the study.

Conclusions: The results from this study suggest that cisatracurium is a safe neuromuscular blocking agent for use in adult severe brain–injured patients with increased ICP under mild hyperventilation and continuous sedation.
Preoperative metoprolol improves cardiovascular stability and reduces oxygen consumption after thoracotomy
Authors: JAKOBSEN C.–J. , BILLE S. , AHLBURG P. , RYBRO L. , PEDERSEN K. D. , RASMUSSEN B.
Published: January 2009

Background: Increased sympathetic activity perioperatively and associated cardiovascular effects play a central role in cardiovascular complications. High thoracic epidural blockade attenuates the sympathetic response, but even with complete pain relief, haemodynamic and endocrine responses are still present. Beta–adrenoceptor blockade is effective in situations with increased sympathetic activity. This study was designed to evaluate the perioperative haemodynamic effect of preoperative βblockade and its influence on the haemodynamic aspects of the surgical stress response.

Methods: Thirty–six otherwise healthy patients undergoing elective thoracotomy for lung resection were randomised doubleblinded to receive either 100 mg metoprolol or placebo preoperatively. Anaesthesia was combined high thoracic epidural block and general anaesthesia. The epidural analgesia was continued during recovery. Patients were monitored with ECG, pulse oximetry, invasive haemodynamic monitoring, arterial blood gases and electrolytes.

Results: After induction of anaesthesia the mean arterial pressure (MAP) decreased in both groups, and decreased further in the placebo group after initiation of the epidural block. The heart rate (HR) was slightly less throughout the observation period after metoprolol. Peroperatively, the only difference in measured haemodynamics was a marginally higher MAP after metoprolol. Postoperative cardiac index (CI) was lower with a lower variability and cardiac filling pressures were slightly higher in the metoprolol group. The oxygen consumption index was higher after placebo throughout the observation period, with no difference in the oxygen delivery.

Conclusion. We found that preoperative β–blockade during combined general anaesthesia and high thoracic epidural blockade stabilised perioperative HR and CI and decreased total oxygen consumption.
The effect of succinylcholine on atracurium–induced neuromuscular block
Authors: ROED J. , LARSEN P. B. , OLSEN J. S. , ENGBÆK J.
Published: January 2009

Background: The interaction between prior succinylcholine and atracurium has been found only after full recovery of succinylcholine block. We investigated whether the effect of succinylcholine on atracurium block may depend on the level of recovery from succinylcholine.

Methods: Fifty patients in 4 groups received atracurium 0.2 mg/ kg when first response (Tl) in train–of–four (TOF) after succinylcholine 1 mg/kg had recovered to 5%, 25%, 75% or 100%. A control group received only atracurium. The following indices were compared: the time from injection of atracurium to maximum block (onset time) and to return of Tl to 25% (duration 25%), maximal depression of Tl, time from 25% to 75% recovery of Tl (interval 25–75%) and time from injection of atracurium to a TOF ratio of 0.75 (duration TOF 0.75).

Results: Onset time was shorter, max Tl depression was greater and duration 25% increased the more succinylcholine recovery progressed. Neither interval 25–75% nor duration TOF 0.75 varied with the level of recovery from succinylcholine. The control group showed a shorter latency and onset time compared to the early (5%) recovery group and a longer onset time and less depressed Tl compared to the late (100%) recovery group. There was no difference between the control group and the early or late recovery groups, respectively for duration 25% or duration TOF 0.75.

Conclusion: The effect of prior administration of succinylcholine on atracurium block depends on the state of recovery from succinylcholine and concerns both its potency, onset and duration characteristics.
Effects of isoflurane on in vivo release of acetylcholine in the rat cerebral cortex and striatum
Authors: SHICHINO T. , MURAKAWA M. , ADACHI T. , NAKAO S. , SHINOMURA T. , KURATA J. , MORI K.
Published: January 2009

Background: Acetylcholine (ACh) is one of the major excitatory neurotransmitters in the central nervous system, and changes in neural activity induced by anesthesia alter the release of ACh. However, the effects of isoflurane, one of the most widely used volatile anesthetics, on ACh release are not known. The present study attempts to clarify the dose–effect relationship of isoflurane on the in vivo release of ACh in rat brains.

Methods: Changes in the extracellular concentration of ACh and choline in the cerebral cortex and striatum induced by 0.5, 1.0, and 1.5 minimum alveolar concentration (MAC) of isoflurane were determined using a brain microdialysis technique.

Results: In the cortex, the ACh release decreased to 30.8±10.1 (mean±SEM), 10.2±4.1, and 8.1±2.9% of basal value by increasing doses of isoflurane, and in the striatum, to 73.3±4.4, 49.2±4.2, and 40.7±4.5%. The ACh release rapidly recovered control levels with the discontinuance of isoflurane. Choline concentration was not changed significantly by isoflurane except for a decrease to 74.8±4.6% in the striatum by 0.5 MAC. In both the cortex and striatum, the choline concentration decreased with the discontinuance of isoflurane to 70.3±13.3, and 68.2±5.4%, respectively.

Conclusion: The fact that all classic anesthetics reported previously, as well as isoflurane, reduce ACh release supports the hypothesis that the suppression of cholinergic cells is, at least in part, one of the mechanisms of anesthesia.
The duration of action of bupivacaine, levobupivacaine, ropivacaine and pethidine in peripheral nerve block in the rat
Authors: DYHRE H. , LÅNG M. , WALLIN R. , RENCK H.
Published: January 2009

Background: There is a current interest in local anaesthetic drugs/formulations exhibiting long durations of sensory block and minor motor–blocking effects.

Objectives: To compare the duration of sensory and motor blockade in peripheral nerve blocks induced by the new agents ropivacaine and levobupivacaine, with that of racemic bupivacaine and pethidine.

Methods: Groups of 8 male Sprague–Dawley rats were subjected to infraorbital (IONB) or sciatic nerve block (SNB) employing 0.2 ml of differently concentrated solutions of bupivacaine, levobupivacaine, ropivacaine or pethidine. The sensory blocking effect in IONB is expressed as (i) the time to elicitation of an abdominal jerk by electrical stimulation at arbitrarily chosen (threshold) intensities (IONB degree 3, 5, 8 and 10), and as (ii) the area under the curve (AUC, threshold intensities vs time). The duration of motor block in SNB is given as the time from injection to regained ability to walk and grip normally with the toes. Comparisons of the dose–effect relationships for the investigated agents were made by analysis of covariance.

Results: In IONB the log (dose)–log (effect) lines for bupivacaine, levobupivacaine and ropivacaine did not deviate from parallelism. The duration of sensory block induced by equimolar doses of these agents was similar, although bupivacaine exerted more pronounced effects than levobupivacaine (AUC by 25%, P=0.001; IONB degree 3 by 14%, P=0.03). In SNB only the log (dose)–log (duration) lines for bupivacaine vs levobupivacaine were found not to deviate from parallelism, both agents exerting similar durations of action. The motor–blocking effects of ropivacaine showed an inverse dose–duration relationship (P=0.019).

Conclusions: Equimolar doses of the investigated local anaesthetics exerted similar durations of sensory blockade in a peripheral nerve block model in the rat.
Comparison of the effect of intravenous ketoprofen, ketorolac and diclofenac on platelet function in volunteers
Authors: NIEMI T. T. , TAXELL C. , ROSENBERG P. H.
Published: January 2009

Background: Nonsteroidal anti–inflammatory drugs (NSAIDs) inhibit prostaglandin synthesis which may result in impaired platelet function. Because NSAIDs have different abilities to inhibit cyclo–oxygenases we compared the effect of intravenous ketoprofen, ketorolac and diclofenac on platelet function in volunteers.

Methods: Ten healthy male volunteers were given ketoprofen 1.4 mg kg‐1, ketorolac 0.4 mg kg‐1 and diclofenac 1.1 mg kg‐1 in saline i.v. on three different occasions, at more than one–week intervals, in a randomized double–blind crossover study. Platelet function was evaluated before (sample 0), 2 (sample 2) and 24 h (sample 3) after the beginning of the infusion.

Results: Two of the volunteers had no secondary platelet aggregation in their aggregation curves before the experiment (sample 0, studied three times) and their results were excluded from the final analysis. Diclofenac inhibited adrenaline (0.9 μg–ml‐1) induced platelet aggregation less (median maximal aggregation 22.5%) than ketoprofen (18.3%) and ketorolac (15.7%) (P<0.05) in sample 2. In the ketorolac group in sample 3 an impairment of adrenaline (0.9 ng ml‐1) induced platelet aggregation was still seen (26.7%) (P<0.05) but not in the other groups. Diclofenac did not affect adenosine diphosphate (ADP) induced platelet aggregation. However, ketorolac caused an impairment in ADP (3 μM and 6 μM) induced platelet aggregation and ketoprofen in ADP (6 μM) induced platelet aggregation in sample 2. Bleeding time was prolonged (P<0.05) after ketoprofen and ketorolac (sample 2) but not after diclofenac. Platelet retention on glass beads was unaffected by the tested drugs.

Conclusion: Ketoprofen, ketorolac and diclofenac caused a reversible platelet dysfunction. Diclofenac had the mildest effect, while platelet dysfunction was still seen 24 h after the beginning of ketorolac.
Deep accidental hypothermia and cardiac arrest rewarming with forced air
Authors: KOLLER R. , SCHNIDER T. W. , NEIDHART P.
Published: January 2009

Background: During the last two cold winters we have treated 5 severely hypothermic patients (temperature below 30C) with active external rewarming rather than with extracorporal circulation and heat exchanger.

Patients: Two patients were found in cardiac arrest, and 3 victims of mountain accidents suffered deep hypothermia without arrest. In one of them, ventricular fibrillation (VF) was converted successfully to a sinus rhythm at a core temperature of 25.9C. Both arrested patients developed an adequate hemodynamic state during resuscitation although they were at very low temperature. All the patients were warmed with a convective cover inflated with warm air of about 38A°C (Bair Hugger). The core temperature increased by approximately 1°C/h in all patients. During rewarming we observed neither an initial drop of the core temperature (afterdrop) nor cardiac arrhythmias. The outcome of all 5 patients was good without neurological sequelae.

Conclusion: We conclude that external rewarming with forced air is a feasible alternative to cardiopulmonary bypass in severely hypothermic patients with electrical activity. This method can be used even in patients with VF because defibrillation can be successfully performed in deep hypothermia. Although afterdrop during external rewarming is feared, we did not observe this phenomenon. Rewarming with forced air is inexpensive, easy to perform and direct access to the patient is possible at any time. It does not require heparinisation and can be used in hospitals where they do not have cardiopulmonary bypass facilities. Thus, this method is particularly useful in situations when the hypothermic patient cannot be transferred to a major medical center.
Microcatheter CSA in a young woman with Fontan repair undergoing elective sterilization
Authors: STANDL T. , CELIK L. , WEYLAND C. , HAFERKORN D. , ESCH J. SCHULTE AM
Published: January 2009

We present the case of a 28–yr–old woman with Fontan anastomosis undergoing elective sterilization. Because of concerns about laparoscopic surgery with capnoperitoneum and positivepressure ventilation, a mini–laparotomy was performed in microcatheter spinal anaesthesia. Tiration of small doses of plain bupivacaine 0.5% supplemented with 5 μg sufentanil provided high cardiocirculatory and respiratory perioperative stability in this patient.
Intraperitoneal bupivacaine for analgesia after laparoscopic cholecystectomy
Authors: MRAOVIČ B. , JURIŠIČ T. , KOGLER‐MAJERIC V. , SUSTIC A.
Published: January 2009

Background The effects of intraperitoneal administration of bupivacaine on pain after laparoscopic cholecystectomy were studied in a prospective, double‐blind, randomised trial. Methods: Eighty ASA 1 and 2 patients were randomly assigned to one of two groups. Immediately after pneumoperi‐toneum was obtained patients in group 1 were given 15 ml of 0.5% bupivacaine injected under direct vision into the hepato‐diaphragmatic space, near and above the hepato‐duodenal ligament and above the gallbladder. At the end of operation another 15 ml of bupivacaine was injected. Patients in group 2 were given 15 ml of 0.9% saline solution in a similar fashion. Postoperative pain was assessed using a visual analogue scale (VAS 100 mm) at 0.5,4, 8,12 and 24 h after surgery. Analgesic consumption was also recorded.
Intra‐arterial regional anaesthesia for hand surgery: a dose‐finding study
Authors: KOSCIELNIAK‐NIELSEN Z. J. , HESSELBJERG L.
Published: January 2009

Background: Intra‐arterial regional anaesthesia (IARA) may be useful for ambulatory hand surgery in patients with poor veins. This randomized, double‐blind study assessed which of the three doses of lignocaine gives the optimal analgesia with a minimum of adverse effects.

Methods: A preservative‐free, alkalinized 0.5% lignocaine 1, 2 or 2.89 mg/kg body weight was injected into the radial arteries of 60 adult patients, allocated to three equal groups, to produce anaesthesia for carpal tunnel releases, capsulotomies, tenosynovectomies, palmar fasciectomies, Z‐plastics, arthro‐plastics, arthrodeses etc.

Results: Surgical analgesia and motor block were best in group 3 (P < 0.01), whereas injection and tourniquet pain scores were similar in the three groups. Onset of analgesia was similar in all groups, and varied between 2 and 15 min. Can‐nulation time, surgery start time and tourniquet time were also similar in all groups, as were operating conditions and patient's acceptance of the method. No significant cardiovascular changes were observed after tourniquet release in any of the groups. Plasma lignocaine concentrations were lowest in group 1 (1 mg/kg) (P < 0.001). Five patients in group 1, seven in group 2 and seventeen in group 3 developed small bruises at the cannulation site (P <0.001). Six patients (two in group 1, three in group 2 and one in group 3) had minor symptoms of lignocaine toxicity after tourniquet release (NS). No other complications were observed.

Conclusions: The highest dose of lignocaine produces best surgical analgesia, without increasing the risk of toxicity. However, many patients receiving this dose will develop bruises at the injection site, and an occasional patient may need supplemental analgesia.
The effects of simulated Bier block IVRA on intracompartmental tissue pressure
Authors: MABEE J. R. , SHEAN C. , ORLINSKY M. , ANDROY L. , CARTER V.
Published: January 2009

Background:Intravenous regional anesthesia (IVRA) is a useful anesthetic method for closed reduction of fractures. However, IVRA has been associated with an increased incidence of compartment syndrome when treating tibial shaft fractures. The purpose of this study was to measure changes in anterior leg compartment pressures during simulated IVRA.

Methods:A volunteer study was performed. An indwelling catheter placed in a consistent location between subjects was used to measure tissue pressure. A vinyl leg splint was used for exsanguination followed by thigh tourniquet inflation (300 mmHg). Normal saline (1.5 mL/kg) was injected through the greater saphenous vein (1.0 mL/s). Pressure measurements were obtained before and after tourniquet inflation, at 10 mL increments during saline injection, and intermittently after volume injection with the tourniquet inflated, then deflated.

Results:There was no significant difference in tissue pressure before (2.4±2.2 mmHg) and after (4.3±3.7 mmHg) tourniquet inflation (P = 0.11). No significant differences in tissue pressure were found as a function of injected volume (P = 0.62), as a function of time following saline injection during tourniquet inflation (P = 0.08), and after tourniquet deflation (P = 0.16).

Conclusions:We conclude that in the normal atraumatic limb, simulated IVRA using normal saline does not increase tissue pressure within the anterior leg compartment.
Inclusion of pethidine in lidocaine for infiltration improves analgesia following tonsillectomy in children
Authors: ELHAKIM M. , SALAM A. Y. ABDUL , EID A. , KASCHEF N. , MOSTAFA B. E.
Published: January 2009

Background:Previous work has demonstrated that pethidine exerts local anaesthetic effects on peripheral nervesin vivo.We examined the effects of infiltration anaesthesia by a combination of pethidine and lidocaine on post‐tonsillectomy pain and restlessness in children.

Methods:Eighty children were randomly allocated to receive peritonsillar infiltration postoperatively with 3 ml of lidocaine 2% (1.5 ml on each side) combined with either 0.1 ml pethidine, 10 mg · ml‐1, (pethidine group) or 0.1 ml normal saline (control group). Pain and behaviour were assessed at 1, 3, 6 and 12 h postoperatively and on the following morning by the patients and by a nurse blinded to previous treatment.

Results:Patients in the pethidine group had lower pain scores than those in the control group at rest as well as swallowing during the whole observation period (P< 0.05). Paracetamol was given to 34/40 children in the control group and to 6/40 children in the pethidine group. The corresponding figures for pethidine administration were 6/40 and 0/40, respectively. Patients in the pethidine group displayed a more rapid return to calm wakefulness than those in the control group (P<0.01).

Conclusions:Inclusion of a low dose of pethidine in lidocaine for tonsillar infiltration improves pain relief after tonsillectomy in children.
Hemodilution significantly decreases tolerance to isoflurane‐induced cardiovascular depression
Authors: SCHOU H. , PEREZ DE V. , LARSSON A. , ROSCHER R. , KONGSTAD L. , WERNER O.
Published: January 2009

Background:Hemodilution is used to reduce the need for allogenic blood transfusion. The aim of this study was to evaluate to what extent acute extreme normovolemic hemodilution affects the circulatory response to isoflurane.

Methods:Ten midazolam‐fentanyl‐pancuronium anesthetized pigs were exposed to isoflurane at end‐tidal concentrations of 0,0.5,1.0,1.5 and 2%, before and after extreme normovolemic hemodilution (hematocrit 33±3% and 11±1%, respectively). Systemic and myocardial hemodynamics and oxygen delivery and consumption were measured.

Results:At zero end‐tidal isoflurane concentration, hemodilution caused an increase in cardiac output (from 157±12 to 227±39 ml kg min‐1, P <0.01) a decrease in systemic vascular resistance (from 39±7 to 18±5 mmHg · L‐1 · min‐1, P <0.01) a decrease in mean arterial blood pressure (MAP) (from 130±13 to 91±13 mmHg, P <0.01) and a decrease in systemic oxygen delivery (from 23.1±2.7 to 11.8±1.7 ml · kg‐1 min‐1, P <0.01). When the end‐tidal isoflurane concentration was increased from 0 to 2% after hemodilution, cardiac output decreased by 86±37 ml · kg‐1 · min‐1, as compared with 36±20 ml · kg‐1 · min‐1 (P <0.01) before hemodilution. Likewise, systemic vascular resistance decreased with increasing isoflurane concentrations; at 2%, the decrease was 7±4 mmHg·L‐1· min‐1 after hemodilution and 18±5 mmHg.L‐1 mid before hemodilution (P < 0.01). At an end‐tidal isoflurane concentration of 2%, MAP had decreased to 43±6 mmHg after hemodilution, and to 61±15 mmHg before hemodilution (kO.01). After hemodilution, isoflurane concentrations above 1% decreased systemic oxygen delivery enough to cause delivery‐dependent oxygen consumption and hyperlactemia; and at 2% isoflurane, myocardial blood flow became insufficient, as indicated by myocardial lactate production.

Conclusions:isoflurane‐induced cardiovascular depression had adverse effects on cardiac output and oxygen delivery during extreme hemodilution because: 1) The vasodilatory effect of isoflurane was insufficient to compensate for the myocardial depression, and also contributed to a critically low arterial blood pressure; 2) A decrease in cardiac output produced delivery‐dependent oxygen consumption and hyperlactemia; and 3) A decrease in myocardial blood flow caused myocardial ischemia which may have exacerbated the myocardial depression.
Differences in hormonal responses to preoperative emotional stress between preschool and school children
Authors: AONO J. , UEDA W. , KATAOKA Y. , MANABE M.
Published: January 2009

Background:The behavior of children under emotional stress differs according to whether they are of preschool or school age.

Methods:To examine the effect of age on hormonal responses to preoperative emotional stress, we measured the concentrations of catecholamines (adrenaline and noradrenaline) and cortisol in 56 healthy boys before surgery.

Results:Among preschool boys (3–5 years old), those showing anxious behavior showed significantly higher cortisol, adrenaline, and noradrenaline concentrations in the blood circulation than those not showing such behavior (P <0.0001, P <0.0001 and P <0.005, respectively). However, among the schoolboys (6–11 years old), anxiety was associated only with the cortisol concentration (P <0.01)

Conclusions: Hormonal responses to preoperative emotional stress in preschool boys differ from those in schoolboys.
Low cardiac output abolishes cardiovascular responses to infra‐renal aortic cross‐clamping in the pig
Authors: SEEMAN‐LODDINC H. , BIBER B. , PONTÉN J. , SUNDEMAN H. , WINSÖ O.
Published: January 2009

Background:Previous data suggest that preoperative myo‐cardial dysfunction is associated with an altered cardiac response to infra‐renal aortic cross‐clamping (AXC). This study was designed to further explore how acute reductions in stroke volume and cardiac output influence the systemic, preportal and renal circulatory responses to AXC.

Methods:In chloralose‐anesthetized normoventilated pigs, graded increases in pericardial pressure (PPERICARD) were obtained by local infusions of dextran. Measurements included cardiac output (CO, thermodilution), mean blood pressure proximal to the aortic clamping site (MAPROX) and ultrasonic flowmetry for portal (QPORT) and renal (QREN) blood flows. In all animals, measurements were made a) prior to AXC, b) at the end of a 5 min AXC period and, c) 5 min following dec‐lamping. These recordings were repeated during control (PPERICARD 0 cmH2O) and during stages with increased PPERICARD (4 and 8 mH2O, respectively).

Results:Pericardial infusions of dextran produced hemody‐namic responses that in magnitude were proportional to PPERICARD levels. Stroke volume, CO and mean arterial pressure decreased, while systemic vascular resistance (SVR) increased.

Conclusions:AXC‐induced systemic, preportal and renal circulatory responses are inhibited during a condition of acutely lowered cardiac output.
Fibreoptic laryngotracheoscopy via the laryngeal mask airway in children
Authors: HOLMSTRÖM A. , ÅKESON J.
Published: January 2009

Background:Fibreoptic laryngotracheoscopy via the laryngeal mask airway ‐ previously reported in adults but not in children ‐ gives a better endoscopic view of the upper airway than does endoscopy via an endotracheal tube.

Results:The laryngeal mask was found to enable laryngotracheoscopy with a flexible 5.0‐mm fibreoptic endoscope with no technical difficulties. Spontaneous ventilation could be readily preserved throughout the endoscopic procedure.

Conclusions:In children anaesthetized with halothane, flexible fibreoptic laryngotracheoscopy via a laryngeal mask is a useful method ‐ offering technical advantages not achieved otherwise ‐ provided that generally approved restrictions to the use of a laryngeal mask airway are taken into account.
The influence of the duration of isoflurane anaesthesia on neuromuscular effects of mivacurium
Authors: JALKANEN L. , MERETOJA O. A.
Published: January 2009

Background:The pharmacodynamic profile of muscle relax‐ants is usually changed by volatile anaesthetics. These changes seem to be time‐dependent, even though few data are available to substantiate this.

Methods:We studied neuromuscular effects of a single dose of mivacurium (0.2 mg·kg‐1) during short and intermediate duration of isoflurane anaesthesia. Forty‐five children 1–10 years of age were randomized to receive 1.5% end‐tidal concentration of isoflurane in N2O/O2 for 10 or 30 min (groups Iso‐10 and Iso‐30, respectively) or to receive nitrous oxide in oxygen for 10 min (Group N2O) before 0.2 mg · kg‐1 of mivacurium was given. Neuromuscular response was recorded by adductor pollicis electromyogram.

Results:The onset time of mivacurium was shorter in Group Iso‐30, 1.7 (1.0–2.3) min than in Group Iso‐10, 2.3 (1.7‐3.3) rnin or Group N2O, 2.3 (1.7‐3.3) min (median with 10–90% percen‐tiles) (P <0.05). In Group Iso‐30 the recovery time of the first EMG response was significantly longer than in groups Iso‐10 and N2O (P <0.0001). Groups Iso‐10 and N2O did not differ from each other.

Conclusions:Our results indicate that the duration of a constant concentration of isoflurane anaesthesia influences significantly the pharmacodynamics of mivacurium. The duration of a volatile anaesthesia is critical when potentiation of NMB is evaluated or compared in neuromuscular studies.
Paediatric cardiac arrest and resuscitation provided by physician‐staffed emergency care units
Authors: SUOMINEN P. , KORPELA R. , KUISMA M. , SILFVAST T. , OLKKOLA K. T.
Published: January 2009

Background:Most paediatric cardiac arrest studies have been conducted in the USA, where paramedics provide prehospital emergency care. We wanted to study the outcome of paediatric cardiac arrest patients in an emergency medical system which is based on physician staffed emergency care units.

Methods:We analysed retrospectively the files of 100 prehospital cardiac arrest patients from Southern Finland during a 10‐year study period. The patients were less than 16 years of age.

Results:Fifty patients were declared dead on the scene (DOS) without attempted resuscitation, and cardiopulmonary resuscitation (CPR) was initiated in 50 patients. The sudden infant death syndrome was the most common cause of arrest in the DOS patients (68%) as well as in those receiving CPR (36%). Asystole was the initial cardiac rhythm in 70% of the patients in whom CPR was attempted. Resuscitation was successful in 13 patients, 8 of whom were ultimately discharged. Six of the patients survived with mild or no disability and 4 of them had near‐drowning aetiology. In multivariate analysis, the short duration of CPR (≤15 min) was the only factor significantly associated with better survival.

Conclusions: Although prehospital care was provided by physicians, the overall rate of survival was found to be equally poor as reported from systems with paramedics. The only major difference between physician‐ and paramedic‐staffed emergency care units is the ability of physicians to refrain from resuscitation already on the scene when prognosis is poor.
Nitric oxide administration after the ventilator: evaluation of mixing conditions
Authors: WESTFELT U. NATHORST , LUNDIN S. , STENQVIST O.
Published: January 2009

Background:Because of the potential toxicity of nitric oxide (NO) and its oxidising product nitrogen dioxide (NO2), any system for the delivery of inhaled NO must aim at stable and predictable levels of NO and as low concentrations as possible of NO2.

Methods:In a laboratory set‐up, we have evaluated mixing conditions in a system where NO is added after the ventilator with continuous flow. Mixing was studied by using carbon dioxide (CO2) as a tracer gas since capnography has a short response time (360 ms) in comparison with measurements of NO with electrochemical fuel cells (response time of 18s). CO2 (in volumes corresponding to an ideal mixture of 1,3 and 6%) was fed, after the ventilator, either into plain breathing tubing, into one or two soda lime absorbers, or into an empty and a soda lime‐filled canister, at different ventilatory rates and different I: E ratios. Samples were drawn from the inspiratory limb close to the Y‐piece. NO was added in the same way and in the same volume as the highest concentration of CO2.

Results:CO2 added to plain tubing resulted in peak levels up to five times the set levels, while addition to a mixing box with an empty and a soda lime‐filled canister resulted in even mixing with gas concentrations close to the ideal. When NO was fed into plain tubing, low levels were measured at the Y‐piece, indicating poor mixing. Gas supply to a mixing chamber resulted in even concentrations.

Conclusions: Even and predictable levels of NO can be obtained with continuous flow of NO to the inspiratory limb, after the ventilator, if a mixing chamber is used. To obtain adequate mixing, the volume of the mixing box should be greater than the tidal volume.