bluuebunny/crossref_metadata_2025 huggingface dataset:
Aerosolized surfactant in lung‐lavaged adult rats: factors influencing the therapeutic response
Authors: Bahlmann H. , Sun B. , Nilsson G. , Curstedt T. , Robertson B.
Published: March 2003

Objective:

To evaluate the effect of aerosolized modified natural surfactant in adult rats with respiratory failure.

Methods: Lung‐lavaged adult rats were treated with aerosolized surfactant, aerosolized saline or a bolus of surfactant. Surfactant was labelled with dimyristoylphosphatidylcholine (DMPC) and human serum albumin was given intravenously for evaluation of lung protein leakage. Blood gases and dynamic compliance were measured intermittently. At the end of ventilation, the lungs were either fixed by vascular perfusion for histological examination or washed for determination of total phospholipids, DMPC and human albumin in the lavage fluid.

Results: Treatment with bolus surfactant led to a quick and sustained restoration of pre‐lavage blood gas values in most animals. The response to aerosolized surfactant varied considerably, with an overall moderate improvement of gas exchange. The saline‐treated group failed to show any significant recovery of lung function. No histopathological differences were found between any of the groups. On average 0.46% of total administered aerosolized surfactant could be recovered. Vascular‐to‐alveolar leakage of human albumin averaged 11%, with no significant differences between the groups. Final values for PaO2 were significantly correlated with total phospholipids in the lavage fluid, and inversely related to the vascular‐to‐alveolar leakage of albumin.

Conclusion: Neither bolus nor aerosolized surfactant influenced lung morphology. Nebulized surfactant improved lung function but the effect was inferior to that obtained with bolus surfactant, and the outcome depended on the balance between the combined pool size of exogenous and endogenous surfactant and the vascular‐to‐alveolar leakage of serum protein.
Two instances of central nervous system toxicity in the same patient following repeated ropivacaine‐induced brachial plexus block
Authors: Ala‐Kokko T. I. , Löppönen A. , Alahuhta S.
Published: March 2003

We describe two instances of central nervous system (CNS) toxicity in the same patient following repeated brachial plexus blocks induced by high doses of ropivacaine (6 mg · kg−1 and 4.5 mg · kg−1, respectively). Although very high total and free plasma concentrations of ropivacaine were found up to 98 min after induction of the blocks, no signs of cardiovascular toxicity apart from hypertension and sinus tachycardia were observed. The measured plasma concentrations are the highest so far reported in the literature. We conclude that this case demonstrates the high cardiovascular safety level of ropivacaine. These high doses, however, resulted in severe toxic CNS symptoms. Therefore, it is stressed that the dose in relation to the weight of the patient must be calculated when administering a large volume of local anesthetic.
Use of sevoflurane in difficult airways
Authors: Kandasamy R. , Sivalingam P.
Published: March 2003

Inhalational induction is one of the recognized methods for the management of difficult airway. Halothane is the usual choice of agent for this purpose. The relatively new agent sevoflurane, which is the least irritant of all the available agents, is emerging as a choice of inhalational agent for both adult and pediatric populations. There are various reports for and against the use of sevoflurane for the management of difficult airway. We describe the use of sevoflurane for the management of difficult airway in four patients presenting with airway problems (Note).
Dual mode antimony electrode for simultaneous measurements of PO2 and pH
Authors: Sjöberg F. , Nilsson G.
Published: March 2003

Background: In biomedical research and clinical medicine there is a demand for potent sensors to measure the components that make up blood gas analyses. Today, as when the electrochemical PO2, PCO2 and pH electrodes were first introduced, these measurements are usually made with the same type of sensor technology. The aims of the present study were, firstly, to find out whether the platinum cathode in the Clark electrode can be replaced by antimony for oxygen measurements (amperometry (A)); secondly, whether, during oxygen measurements, the inherent corrosion potential of the antimony metal can be used for measurement of pH in the same measurement area (potentiometry (P)).

Methods: An electrode of purified, crystallographically orientated monocrystalline antimony (COMA) connected to a reference electrode (silver‐silver chloride) was used for the P measurements. Measurements of A (at −900 mV) and P were made in an aqueous environment regulated for oxygen, pH, and temperature.

Results: Reproducible oxygen sensitivities of 0.925 nA/% oxygen (2% CV (coefficient of variation)) (A), 10.7 mV/% (P), and 0.7mV/% (P) were found in the oxygen range: 0–21%, <5%, and above 5%, respectively. The pH sensitivity was 57 mV/pH unit (P). Oxygen and pH measurements were less accurate at oxygen concentrations close to 0%.

Conclusions: Both the oxygen and pH part of the composite electrode signal can be identified by this dual mode technique (A and P). The sensor seems to be promising as it provides measurements of two separate variables (oxygen and pH) and also has the desirable characteristics of a solid state sensor.
Bradycardia and asystolic cardiac arrest during spinal anaesthesia: A report of five cases
Authors: Løvstad R. Z. , Granhus G. , Hetland S.
Published: March 2003

Sudden, severe bradycardia/asystolic cardiac arrest are considered infrequent, but are certainly the most serious complications of spinal anaesthesia. We report four cases of primary asystole and one of severe bradycardia in young to middle‐aged, healthy patients scheduled for minor surgery at the day surgery unit. Bradycardia/asystole were not related to respiratory depression or hypoxaemia/hypercarbia; they occurred at different time intervals after the onset of spinal anaesthesia (10–70 min) and, apparently, were not dependent on the level of sensory block, which varied between T3 and T8. One patient was nauseated seconds before the asystole, otherwise there was no warning signs. All the patients were easily resuscitated with the prompt administration of atropine and ephedrine and, in the case of cardiac arrest, cardiac massage and ventilation with oxygen. One patient was treated with a small dose of adrenaline. Four patients had the surgery, as planned; one had the surgery postponed. All the patients were discharged from hospital in good health and did not suffer any sequelae.
The effects of clonidine on ropivacaine 0.75% in axillary perivascular brachial plexus block
Authors: Erlacher W. , Schuschnig C. , Orlicek F. , Marhofer P. , Koinig H. , Kapral S.
Published: March 2003

Introduction:

The new long‐acting local anesthetic ropivacaine is a chemical congener of bupivacaine and mepivacaine. The admixture of clonidine to local anesthetics in peripheral nerve block has been reported to result in a prolonged block. The aim of the present study was to evaluate the effects of clonidine added to ropivacaine on onset, duration and quality of brachial plexus block.

Methods: Patients were randomly allocated into two groups. In group I brachial plexus was performed using 40 ml of ropivacaine 0.75% plus 1 ml of NaCL 0.9%, and in group II brachial plexus was performed using 40 ml of ropivacaine 0.75% plus 1 ml (0.150 mg) of clonidine. Onset of sensory and motor block of radial, ulnar, median and musculocutaneous nerve were recorded. Motor block was evaluated by quantification of muscle force, according to a rating scale from 6 (normal contraction force) to 0 (complete paralysis). Sensory block was evaluated by testing response to a pinprick in the associated innervation areas. Finally, the duration of the sensory block was registered. Data were expressed in mean±SD. For statistical analysis a Student t‐test was used. A P‐value of ≤0.05 was considered as statistically significant.

Results: The duration of blockade was without significant difference between the groups. Group I: 718±90 min; Group II: 727±117 min. There was no intergroup difference in sensory and motor onset or in quality of blockade.

Conclusion: The addition of clonidine to ropivacaine 0.75% does not lead to any advantage of block of the brachial plexus when compared with pure ropivacaine 0.75%.
Pre‐incisional epidural ketamine, morphine and bupivacaine combined with epidural and general anaesthesia provides pre‐emptive analgesia for upper abdominal surgery
Authors: Wu C. T. , Yeh C. C. , Yu J. C. , Lee M. M. S. , Tao P. L. , Ho S. T. , Wong C. S.
Published: March 2003

Background: Previous studies have shown that N‐methyl‐D‐asparate (NMDA) receptor antagonists provide a pre‐emptive analgesic effect in humans. This study investigated the benefits of pre‐emptive analgesia for upper abdominal surgery, using pre‐incisional epidural ketamine + morphine + bupivacaine (K+M+B) treatment for achieving postoperative pain relief.

Methods: Sixty ASA 1–2 patients scheduled for upper abdominal surgery were allocated to three groups in a randomized, single‐blinded study. Patients in the control group (I) received general anaesthesia followed by an infusion of normal saline. Group II and III patients received general anaesthesia with a continuous epidural infusion of 2% lidocaine. Thirty minutes after the incision in groups I and II, an epidural pain control regimen was administered using ketamine (10 mg) and morphine (1 mg) in 10 ml of 0.085% bupivacaine (K+M+B). Group III patients also received K+M+B, but it was administered 10 min after the 2% lidocaine injection and 30 min before skin incision. All patients received an epidural pain control regimen (q12 h) for 3 days after their first injection. Patient‐controlled analgesia (PCA) with morphine was used to control subsequent postoperative pain. During the 3‐day period following surgery, duration to PCA trigger (h), morphine consumption (mg), pain intensity at rest and when coughing/moving, and analgesic‐related adverse effects were recorded. The VAS scale (0–10) was used to assess pain intensity.

Results: Median times to first PCA trigger were 1.2 (0.5–2.0) h, 3.0 (0.7–4.2) h, and 4.0 (2.5–7.5) h for groups I, II, and III, respectively. Both the incident and resting pain scores were consistently lower for group III patients than groups I and II. The number of PCA triggers (all attempts/successful triggers) during the day following surgery were 14.0 (3–30)/8.0 (3–24) times, 10.0 (3–23)/6.0 (2–20) times, and 7.0 (3–12)/4.5 (1–10) times for groups I, II, and III. Total morphine consumption for the 3‐day observation period was 12.5 (3–42) mg, 10.5 (2–29) mg, and 6.0 (1–20) for groups I, II, and III, respectively.

Conclusion: Pre‐incisional epidural K+M+B treatment combined with continuous epidural anaesthesia and general anaesthesia provides an ideal pre‐emptive analgesic therapy, exhibiting better postoperative pain relief than general anaesthesia and post‐incisional K+M+B treatment.
Platelet dysfunction after intravenous ketorolac or propacetamol
Authors: Niemi T. T. , Backman J. T. , Syrjälä M. T. , Viinikka L. U. , Rosenberg P. H.
Published: March 2003

Background: Paracetamol is a weak cyclo‐oxygenase inhibitor in vitro. A recent study in children has shown that high doses of paracetamol are effective and safe. We studied the effect of propacetamol on haemostasis in adult volunteers.

Methods: Ten volunteers were investigated in a double‐blind, randomized, crossover study. They received propacetamol 60 mg kg−1 or ketorolac 0.4 mg kg−1 in saline i.v. (30 min) in two different sessions. Platelet function was evaluated before the test infusion (S‐0), two (S‐2) and 24 h (S‐24) after the start of the infusion. Coagulation parameters (PT, APTT, factor V and VII activities) were measured at S‐0, S‐24 and 48 h (S‐48).

Results: One of the volunteers had no secondary platelet aggregation in S‐0 and was excluded from the final analysis. Two hours (S‐2) after propacetamol and ketorolac administration the adrenaline (0.9 μg ml−1 and 9.0 μg ml−1) induced maximal platelet aggregation was decreased compared with S‐0. At S‐2 platelet aggregation was inhibited more after ketorolac than after propacetamol. At 24 h after ketorolac, but not after propacetamol, there was still a decrease in the adrenaline‐induced maximal platelet aggregation. Propacetamol did not affect adenosine diphosphate (ADP)‐induced maximal platelet aggregation, whereas ketorolac decreased 3 and 6 μM ADP‐induced maximal platelet aggregation at S‐2 and S‐24. However, 2 h after both ketorolac and propacetamol, thromboxane B2 (TxB2) concentration decreased in platelet rich plasma after 5 min aggregation induced by 8 μM ADP. Coagulation was unaffected.

Conclusion: Propacetamol 60 mg kg−1 i.v. causes reversible platelet dysfunction demonstrated by a decrease in maximal platelet aggregation and TxB2 concentration. After 0.4 mg kg−1 ketorolac i.v. platelet aggregation and TxB2 formation are inhibited more in comparison with propacetamol, and platelet dysfunction is still seen after 24 h.
Effects of conventional physiotherapy, continuous positive airway pressure and non‐invasive ventilatory support with bilevel positive airway pressure after coronary artery bypass grafting
Authors: Matte P. , Jacquet L. , Van Dyck M. , Goenen M.
Published: March 2003

Background: Coronary artery bypass graft (CABG) surgery with the use of mammary arteries is associated with severe alteration of lung function parameters. The purpose of the present study was to compare the effect on lung function tests of conventional physiotherapy using incentive spirometry (IS) with non‐invasive ventilation on continuous positive airway pressure (CPAP) and with non‐invasive ventilation on bilevel positive airway pressure (BiPAP or NIV‐2P).

Methods: Ninety‐six patients were randomly assigned to 1 of 3 groups: NIV‐2P (1 h/3 h), CPAP (1 h/3 h) and IS (20/2 h). Pulmonary function tests and arterial blood gases analyses were obtained before surgery. On the 1st and 2nd postoperative days, these parameters were collected together with cardiac output and calculation of venous admixture.

Results: For the 3 groups a severe restrictive pulmonary defect was observed during the 1st postoperative day. On the 2nd postoperative day, in opposition to IS, intensive use of CPAP and NIV‐2P reduced significantly the venous admixture (P<0.001) and improved VC, FEV1 and PaO2 (P<0.01).

Conclusion: We conclude that preventive use of NIV can be considered as an effective means to decrease the negative effect of coronary surgery on pulmonary function.
Effect of pentaglobin and piperacillin on survival in a rat model of faecal peritonitis: importance of intervention timings
Authors: Jacobs S. , Sobki S. , Morais C. , Tariq M.
Published: March 2003

Background: Faecal peritonitis is a progressive pathophysiological condition which may lead to multiple organ failure and death. The reason for the associated morbidity and mortality could be attributed to the fact that some of the subtle alterations in cellular function that occur during the early stage of peritonitis are unidentified and consequently missed, leading to inadequate or delayed intervention. Recent studies have shown that early treatment with antibiotic and antisera containing antibodies to lipopolysaccharide (immunoglobulin) improve the survival rate in these patients. The present investigation was undertaken to study the effect of pentaglobin and piperacillin with particular attention to time lag of drug intervention on animal survival following experimental peritonitis.

Methods: Experimental peritonitis was produced by inoculating 1 ml/kg of faecal suspension (2:1 w/v in saline) into the peritoneal cavity. Two groups of animals were treated with pentaglobin (4 ml/kg) or piperacillin (1000 mg/kg) respectively, whereas rats in another group received both drugs simultaneously. The first dose of each drug was given at 4 h, 6 h, 8 h and 12 h after faecal inoculation followed by 3 additional doses at 8‐h intervals. For biochemical studies, separate groups of animals were used in which the treatment was started 4 h after faecal inoculation and the animals were killed at 12 h after the treatment.

Results: Both piperacillin and pentaglobin prolonged survival time of animals which received the treatment within 6 h of faecal insult. The combination of pentaglobin plus piperacillin produced better results as compared to the individual effect. There was a significant decrease in serum superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) and increase in catalase following faeces‐induced septicaemia, suggesting a significant increase in oxidative stress. The changes in enzyme levels were significantly attenuated by both the drugs.

Conclusion: The findings suggest that intervention with a combination of pentaglobin and antibiotics within 6 h of peritonitis might significantly improve survival rate in rat.
Recovery characteristics of sevoflurane or halothane for day‐case anaesthesia in children aged 1–3 years
Authors: Viitanen H. , Baer G. , Annila P.
Published: March 2003

Background: Our objective was to compare the recovery characteristics of sevoflurane and halothane for short day‐case anaesthesia in a specifically limited age group of children 1–3 yr.

Methods: Eighty unpremedicated children undergoing day‐case adenoidectomy were randomly assigned to receive inhalational induction with either sevoflurane 8% or halothane 5% and nitrous oxide in oxygen (70/30) via a face mask. Tracheal intubation was performed without a muscle relaxant. Anaesthesia was continued with the volatile anaesthetic, adjusted to maintain heart rate and blood pressure within ±20% of initial values. Recovery was evaluated using a modified Aldrete score, a Pain/Discomfort scale and by measuring recovery end‐points. A postoperative questionnaire was used to determine the well‐being of the child at home until 24 h after discharge.

Results: Emergence and interaction occurred significantly earlier after sevoflurane than halothane but discharge times were similar. More children in the sevoflurane group achieved full Aldrete scores within the first 30 min after anaesthesia, although this group suffered more discomfort during the first 10 min. The amount of postoperative analgesic administered was higher and the first dose given earlier in the sevoflurane group. Postoperative vomiting was more common with halothane, but side‐effects in the two groups were otherwise similar in the recovery room and at home.

Conclusions: In children 1–3 yr, sevoflurane provided more rapid early recovery but not discharge after anaesthesia of <30‐min duration. Apart from more vomiting with halothane and more discomfort during the first 10 min after awakening with sevoflurane, the quality of recovery was similar with the two anaesthestics.
Intramuscular ephedrine reduces emesis during the first three hours after abdominal hysterectomy
Authors: Hagemann E. , Halvorsen A. , Holgersen Ø. , Tveit T. , Ræder J. C.
Published: March 2003

Background: We tested the hypothesis that intramuscularly administered ephedrine prevents postoperative nausea and vomiting. Ephedrine is cheap, and for this indication poorly documented.

Methods: One hundred and nine patients undergoing elective abdominal hysterectomy under general anaesthesia were studied in a randomized, double‐blind placebo‐controlled study. Ten minutes before the end of the procedure patients received either ephedrine 0.5 mg/kg i.m. or placebo. The patients were closely observed for 24 h for postoperative nausea or vomiting (PONV) and received a standardized two‐step antiemetic treatment of i.v. metoclopramide 10 mg, supplemented with ondansetron 4 mg i.v. if needed.

Results: The ephedrine treated patients had significantly less nausea, retching and vomiting, and need of antiemetic rescue during the first 3 h postoperatively compared with the placebo patients. No difference between the groups was evident in the 3–24 h postoperative observation period. All the patients with PONV during 0–3 h experienced PONV in the 3–24 h period. Treatment or prophylaxis with one drug was less efficient than two or more drugs combined. No significant differences in hypotension, tachycardia or other side‐effects between the groups were noted.

Conclusion: Ephedrine 0.5 mg/kg i.m. administered at the end of abdominal hysterectomy has a significant antiemetic effect during the first 3 h after administration with no evident side‐effects.
Intermittent atrial level right‐to‐left shunt with temporary hypoxemia in a patient during support with a left ventricular assist device
Authors: Kilger E. , Strom C. , Frey L. , Felbinger T.W. , Pichler B. , Tichy M. , Rank N. , Wheeldon D. , Kesel K. , Schmitz C. , Reichenspurner H. , Polasek J. , Weis F. , Goetz A. E.
Published: March 2003

We report a 56‐year‐old male patient developing hypoxemia after surgical replacement of infected valves of a left ventricular assist device (LVAD, NovacorTM) which had supported him during the previous 15 months. Contrast transesophageal echocardiography (TEE) revealed an atrial septal defect with intermittent right‐to‐left shunt across a patent foramen ovale.

We postulate that the shunt detected in this patient occurred as a consequence of reduced pulmonary vascular compliance due to positive end‐expiratory pressure (PEEP) and an increase of mean intrathoracic pressure. Furthermore, we hypothesize that synchronized LVAD operation exacerbates any potential right‐to‐left shunt due to the profound left ventricular unloading which occurs during LVAD support.

In this first report of a right‐to‐left shunt from a previously unrecognized patent foramen ovale in a NovacorTM patient, the subsequent transient hypoxemia could be managed by avoiding PEEP of more than 3 mmHg, and mean airway pressure of more than 11 mmHg and by careful volume replacement in order to prevent the pump from completely emptying the left ventricle (LV) and the left atrium (LA). Thus, prior to every LVAD implantation a transesophageal contrast echocardiography with Valsalva maneuver should be performed to identify intracardiac right‐to‐left shunt.
Cardiac output measurements during cross‐clamping of the descending thoracic aorta in pigs
Authors: Aadahl P. , Aakhus S. , Sæther O. D. , Stømholm T. , Myhre H. O.
Published: March 2003

Background: Cross‐clamping of the descending thoracic aorta (XC) induces an increase in cardiac output (CO). The intention of this study was to evaluate the high CO during XC by the use of clinically available methods (thermodilution and pulsed Doppler ultrasound) compared to transit‐time ultrasound flowmetry of the ascending aorta as the gold standard.

Method:

Ten pigs were anaesthetised with ketamine and fentanyl. The descending thoracic aorta was cross‐clamped for 30 min, and cardiac output was measured with pulmonary artery thermodilution technique, pulsed Doppler ultrasound on the aortic annulus and transit‐time ultrasound flowmetry of the ascending aorta.

Results: At 15 min following XC, CO increased from 1.7 l/min to 4.6 l/min measured with transit‐time ultrasound (P<0.05). With thermodilution technique, CO increased from 2.6 l/min to 5.7 l/min (P<0.05), and from 2.4 l/min to 6.0 l/min measured with Doppler ultrasound (P<0.05). There was an increase in mean arterial pressure of 81% and heart rate increased 76% (P<0.05).

Conclusion: XC of the descending thoracic aorta induces an increase in CO of 171%. Thermodilution and pulsed Doppler ultrasound are reliable methods for detecting high cardiac output during thoracic aortic surgery.
Needle design does not affect the success rate of spinal anaesthesia or the incidence of postpuncture complications in children
Authors: Kokki H. , Heikkinen M. , Turunen M. , Vanamo K. , Hendolin H.
Published: March 2003

Background: In adults, pencil‐point spinal needles are believed to be less traumatic and therefore to be superior compared to cutting‐point needles with respect to success rate and postpuncture complications. The aim of this randomised, parallel groups and prospective study was to record the success rate and to evaluate the incidence of complications following spinal anaesthesia with the two types of needles in children.

Methods: We studied 215 children aged 1 to 18 years. A 25‐gauge needle was used in children up to 7 years (n=96) and a 27‐gauge needle in older children (n=119). During lumbar puncture with either a cutting‐point (n=109) or a pencil‐point (n=106) spinal needle, we recorded puncture characteristics and the success of cerebrospinal fluid (CSF) aspiration. Hyperbaric bupivacaine 5 mg ml−1 at a dose of 0.3–0.4 mg kg−1 was used for the spinal anaesthesia. The incidence of postdural puncture complications was recorded from diaries completed by the children and parents one week after the lumbar puncture.

Results: The success rate of the spinal anaesthesia was 97% without difference between the needles. The success rate was higher when the aspiration of CSF was easy compared to if it was difficult (98% vs. 88%, P=0.02). Two hundred and seven diaries were returned (97%). Twenty‐four children developed a headache, 8 of which were classified as a postdural puncture headache (PDPH), 6 with the cutting‐point needle and 2 with the pencil‐point needle (n.s.). Nine children developed signs of transient radicular irritation with no difference between the needles.

Conclusion: Both types of spinal needles can be used in children, and a free aspiration of CSF results in a high success rate of the spinal block. Postpuncture complications are as common in children as in adults.
Comparison of combined spinal epidural anesthesia and epidural anesthesia for cesarean section
Authors: Choi D. H. , Kim J. A. , Chung I. S.
Published: March 2003

Background: Epidural anesthesia (EA) is popular for cesarean section, but has some drawbacks such as incomplete block, inadequate muscle relaxation and delayed onset. Combined spinal epidural anesthesia (CSEA) has gained increasing interest as it combines the reliability of a spinal block and the flexibility of an epidural block. We investigated the efficacy of CSEA that combines the main spinal and the supporting epidural anesthesia, comparing with pH‐adjusted EA, for cesarean section.

Methods: Sixty‐four pregnant women at full term were divided into two groups. Patients in the CSEA group (n=32) were given 1.5–1.6 ml of 0.5% hyperbaric bupivacaine intrathecally, followed by 10 ml of 0.25% plain bupivacaine through the epidural catheter 10 min later. Patients in the EA group (n=32) received 20–25 ml of 2% lidocaine which was already mixed with 0.1 ml of 0.1% epinephrine, 100 g of fentanyl and 1.5 ml of 8.4% sodium bicarbonate. The quality and side effects of surgical anesthesia, neonatal state, and postoperative course were compared between the two groups.

Results: In the EA group, 22% (7 cases) complained of intraoperative pain but none in the CSEA group (P=0.011). Muscle relaxation and motor block were much better in the CSEA group (P<0.001 and P=0.011 each). Significantly more women in the EA group had shivering (P=0.001). They also had more nausea and vomiting but the differences were not significant. Not only the time to T4 block (9.7 vs. 18.3 min, mean, P<0.001) but also the stay in the postanesthesia care unit, recovery of sensory and motor block and start of postoperative pain were all significantly shorter in the CSEA group. No one in either group had post‐dural puncture headache (PDPH).

Conclusion: We can conclude that, when combining the main spinal and the supporting epidural anesthesia, CSEA has greater efficacy and fewer side effects than the pH‐adjusted EA in cesarean sections.
The pharmacokinetics of anesthetic drugs and adjuvants during cardiopulmonary bypass
Authors: Mets B.
Published: March 2003

The institution of cardiopulmonary bypass during cardiac surgery has profound effects on the plasma concentration of drugs and thus their therapeutic effectiveness. These changes occur through acute hemodilution, altered plasma protein binding, hypotension, as well as the use of hypothermia and heparin administration. Isolation of the lungs from the circulation and the possible sequestration of drugs in the bypass circuit also affect drug plasma concentrations on bypass. The individual characteristics of the drug in question are also important in determining the final plasma concentration: Lipid soluble drugs with a high volume of distribution may be more readily taken up by bypass equipment, but the initial fall in concentration at the start of cardiopulmonary bypass may be more readily counteracted by back diffusion into plasma, if large tissue stores have accumulated. The extent of the drug’s plasma protein binding is of importance as the effective free fraction in plasma for highly bound drugs will be sensitive to changes in plasma protein binding brought on by factors such as hemodilution, heparin administration as well as alpha, acid‐glycoprotein binding. Clearly the fate of drugs administered before or on bypass is complex and can only be accurately determined by specific studies evaluating drug plasma concentrations. This review updates the available data on anesthetics and drugs used during cardiac surgery in order that anesthetists may predict better the likely effect of drugs administered before or during cardiopulmonary bypass.
Quality of recovery in children: sevoflurane versus propofol
Authors: Picard V. , Dumont L. , Pellegrini M.
Published: March 2003

Background: Sevoflurane, with its low pungency and low blood and tissue solubility, is an attractive anaesthetic in paediatric outpatient surgery. Propofol‐anaesthesia is recognised for its rapid and clear‐headed emergence. This study was designed to compare emergence and recovery characteristics of sevoflurane and propofol anaesthesia for tonsillectomy in children.

Methods: Children aged 3–10 years, undergoing elective tonsillectomy, were randomly assigned to receive propofol (n=25, induction with 3 mg · kg−1, maintenance with 100–250 μg · kg−1 · min−1) or sevoflurane anaesthesia (n=25, induction 7 vol.%, maintenance 2–3 vol.%). Tracheal intubation was performed with alfentanil 20 μg · kg−1 and atracurium 0.5 mg · kg−1. Ventilation was controlled to maintain normocapnia and all patients received N2O/O2 (60:40 vol.%) for induction and maintenance of anaesthesia. At the end of surgery infiltration of the operative sites with bupivacaine 2 mg · kg−1 was provided for postoperative analgesia. Emergence, recovery, discharge times, and incidence of side effects were compared between the two groups.

Results: Time to extubation (14 vs 15 min), time to response to simple verbal command (21 vs 21 min) and time to discharge from the recovery room (45 vs 50 min) were similar in the sevoflurane and propofol groups, respectively. There was a significantly greater incidence of postoperative agitation in the sevoflurane group (46%) compared with the propofol group (9%) (P=0.008). This did not, however, delay discharge from the recovery room. The incidence of nausea and vomiting was not significantly different (8% vs 0%; P=0.49).

Conclusion: In children, recovery from anaesthesia with sevoflurane results in a higher incidence of agitation compared with propofol.
The impact of 4‐chloro‐m‐cresol in heparin formulas on malignant hyperthermia: in vitro and in vivo
Authors: Anetseder M. , Ritter L. , Horbaschek H. , Hartung E. , Roewer N.
Published: March 2003

Background: The preservative 4‐chloro‐m‐cresol (4CmC) is a specific activator of sarcoplasmic Ca2+ release and induces contractures in skeletal muscles of malignant hyperthermia susceptible (MHS) patients in vitro. Clinical formulas of heparin contain 4CmC. We studied whether (a) these heparin formulas induce contractures in isolated MHS and normal (MHN) human skeletal muscles and whether (b) significant serum levels of 4CmC are reached after heparinization in cardiopulmonary bypass patients.

Methods: (a) In vitro, muscle bundles of 16 MHS and 22 MHN patients were exposed to the heparin formula Liquemin® (containing 4CmC 0.08 mg/500 IU), to chlorocresol and to preservative‐free heparin in the in vitro contracture test. (b) In vivo, serum 4CmC levels of 12 patients receiving Liquemin® 500 IU/kg before cardiopulmonary bypass were determined at 1, 5 and 60 min by high‐pressure liquid chromatography.

Results: (a) For Liquemin® and 4CmC, significant contractures were measured with MHS muscles compared to MHN muscles at 61.4 μM 4CmC. (b) In control sera, the detection threshold for 4CmC was 4 μM. Concentrations of 4CmC in all patients’ serum samples were below this threshold.

Conclusion: Heparin formulas, containing 4CmC, induce dose‐dependent contractures in vitro in MHS human skeletal muscle at about 60 μM 4CmC. However, in vivo, 4CmC serum concentrations with therapeutic heparinization are less than 1/15 of the in vitro concentration. The lipophilicity of 4CmC with a high volume of distribution may account for these findings. MHS patients seem not to be at risk from clinical heparin formulas containing chlorocresol.
Treatment of severe low back pain with opioids during pregnancy in a patient with incomplete tetraplegia
Authors: Sabatowski R. , Radbruch L. , Grond S. , Göhring U.‐J.
Published: March 2003

We report a case of severe low back pain during pregnancy in a woman with incomplete tetraplegia due to viral myelitis. The pain was interpreted as a radiculopathy in the presence of multiple herniated discs. Surgical intervention was not indicated and physiotherapy failed; therefore, a symptomatic drug treatment with oral analgesics was initiated. To minimise the total daily opioid dosage and the potential risk of a neonatal withdrawal syndrome due to opioids, the route of administration was changed from oral to epidural. Adequate pain relief was maintained with this regimen until caesarean section was necessary. The neonatal withdrawal symptoms after delivery were mild. Residual pain slowly diminished after delivery and the patient was able to discontinue opioid therapy. The aetiology of low back pain remains unclear and may be multifactorial.
Peroperative cardiovascular stability during brainstem surgery. The use of high‐dose methylprednisolone compared to dexamethasone
Authors: Mursch K. , Buhre W. , Behnke‐Mursch J. , Markakis E.
Published: March 2003

Background: In neurosurgical procedures within brainstem structures, corticosteroids are routinely administered to prevent oedema and to reduce intraoperative trauma. After replacing the routine administration of dexamethasone (DX) by high‐dose methylprednisolone (MP) during surgery for tumours within brainstem structures, a decreased incidence of intraoperative haemodynamic instability events was observed. To test this hypothesis, a retrospective analysis was performed.

Methods: Peroperative data of 62 surgical procedures of brainstem tumours were retrospectively analysed with respect to haemodynamic instability requiring changes in surgical strategy and/or emergence medication with vasoactive drugs. Severe changes in haemodynamic parameters were defined as a significant increase or decrease in heart rate and/or mean arterial blood pressure greater than 30% compared to baseline values. From 1988 to 1994, intravenous dexamethasone was given peroperatively in 33 patients. After a bolus of 1 mg kg−1 body weight (BW) 30 min preoperatively, 0.2 mg kg−1 were given every 4 h. From 1994 until now, methylprednisolone was administered instead of dexamethasone in 29 patients. After an initial bolus of 30 mg kg−1 BW immediately before surgery, 5.4 mg kg−1 h−1 were given 23 h postoperatively.

Results: The results of this retrospective analysis suggest that the number of operations with episodes of bradycardia, arterial hypotension (P<0.05), tachycardia and arterial hypertension (P<0.005) was significantly decreased in the group of patients treated with high‐dose methylprednisolone.

Conclusion: The retrospective analysis of the clinical data showed that the routine use of high‐dose methylprednisolone was associated with a decreased incidence of haemodynamic instability in a selected group of patients undergoing brainstem surgery. This finding has to be proven in prospective double‐blind controlled studies.
Low‐dose dopexamine in patients undergoing hemihepatectomy: an evaluation of effects on reduction of hepatic dysfunction and ischaemic liver injury
Authors: Marx G. , Leuwer M. , Höltje M. , Bornscheuer A. , Herrmann H. , Mahr K. H. , Vangerow B. , Heine J. , Piepenbrock S. , Rueckoldt H.
Published: March 2003

Background: Hepatic dysfunction is a common problem in patients after hemihepatectomy. Treatment with low‐dose dopamine has been shown to be beneficial in hemihepatectomy patients. We hypothesized that dopexamine, a synthetic vasoactive catecholamine, due to its specific pharmocodynamic profile may be more effective in reducing hidden ischaemic episodes in the hepato‐splanchnic region during and after temporary total cross‐clamping of hepatic inflow in these patients.

Methods: The effects of low‐dose dopexamine on hepatic venous haemoglobin oxygen saturation (Shv¯O2), hepatic venous lactate level, monoethylglycinxylid (MEGX) formation, hepatic synthetic function and indicators for hepatic cell damage were studied during hemihepatectomy and for 16 h postoperatively in hemihepatectomy patients and compared to those of low‐dose dopamine. In a prospective, double‐blind clinical study 20 patients received randomly either dopexamine (DPX) 0.5 μg kg−1 min−1 (n=10) or dopamine (DO) 2.5 μg kg−1 min−1 (n=10). Infusions were started after induction of anaesthesia and continued 16 h postoperatively. Hepatic vein, radial and pulmonary artery were catheterized. Measurements were carried out after induction of anaesthesia, after total cross‐clamping of hepatic inflow, and at 2 h and 16 h postoperatively.

Results: There were no differences in systemic haemodynamics, oxygenation, Shv¯O2, serum aminotransferases or MEGX levels between the groups. At 16 h postoperatively prothrombin and antithrombin III levels were significantly lower while hepatic venous lactate was significantly higher in the DPX group compared to the DO group.

Conclusion: In patients undergoing hemihepatectomy, we could not reveal superior hepatoprotective effects of low‐dose dopexamine compared to low‐dose dopamine.
Does halothane or isoflurane affect hypoxic and post‐hypoxic vascular response in rabbit aorta?
Authors: Haddad E. , Lebuffe G. , Boillot A. , Imbenotte M. , Vallet B.
Published: March 2003

Background: Halothane and isoflurane affect differently endothelium‐dependent and ‐independent vasorelaxation at 95% O2. In addition, hypoxic vascular response might involve endothelium‐dependent and ‐independent mechanisms. Therefore, we investigated, in rabbit aortic rings, 1) the influence of halothane and isoflurane on vasodilation at 95% O2 and on hypoxic‐induced vasorelaxation at 0% O2 and 2) the influence of halothane and isoflurane on endothelium‐dependent and ‐independent post‐hypoxic vascular response.

Methods: Endothelium‐intact and endothelium‐denuded rabbit aortic rings were used. Phenylephrine precontracted rings were exposed, at 95% O2, to acetylcholine (ACh, 10−9 to 10−4 M) or sodium nitroprusside (SNP, 10−9 to 10−4 M) in the presence or absence of anaesthetic at 1 or 2 MAC. Precontracted rings were also exposed to an acute reduction in O2 from 95% to 0% followed by an acute reoxygenation with 95% O2 in the absence or presence of anaesthetic at 1 or 2 MAC.

Results: At 95% O2, halothane decreased endothelium‐dependent relaxation to ACh, while endothelium‐independent relaxation to SNP was decreased only at 2 MAC. Isoflurane did not modify ACh‐ or SNP‐induced relaxation. At 0% O2, neither halothane nor isoflurane altered the hypoxic vascular relaxation. Post‐hypoxic response was not changed either.

Conclusion: Our results indicate that halothane and isoflurane do not alter vascular hypoxic response in conductance arteries.
Effects of etomidate on free intracellular amino acid concentrations in polymorphonuclear leucocytes in vitro
Authors: Mühling J. , Weiss S. , Knülle V. , Sablotzki A. , Dehne M. G. , Hempelmann G.
Published: March 2003

Background: Previous studies have shown the inhibitory effects of etomidate on polymorphonuclear leucocyte (PMN) function. No reports exist, however, regarding free intracellular amino acid metabolism, although physiological cell metabolism and basic cell functions rely upon a balanced intracellular amino acid content and the cell membrane‐mediated separation of cellular amino acids from the extracellular plasma amino acid pool. Thus, in the current study, we evaluated the effects of etomidate on free intracellular amino acid metabolism in PMN.

Methods: With ethics committee approval, blood was withdrawn from 35 healthy volunteers and incubated (1 h) either with 0 μg/ml, 0.0156 μg/ml, 0.0625 μg/ml or 0.5 μg/ml of etomidate as well as with its additives (propylene glycol and Lipofundin MCT® 10%). The PMN were separated using standardized Percoll®‐gradient and centrifugation procedure before deep‐freezing and lyophilization techniques were employed. All PMN samples were dissolved in methanol/H2O, and the concentrations of free intracellular amino acids were monitored using both novel advanced PMN‐separation and high‐performance liquid chromatography techniques.

Results: Etomidate influenced important free amino acid profiles in PMN in a dose‐dependent manner, indicating complex changes of cellular amino acid turnover. Neither propylene glycol nor Lipofundin MCT® 10% changed free amino acid concentrations in PMN.

Conclusions: For the first time, the effects of etomidate on free intracellular amino acid metabolism in PMN have been investigated. Our results draw attention to the biochemical pathways which may be involved in etomidate‐induced alterations in PMN function and cellular immunocompetence.
Ropivacaine‐clonidine combination for caudal blockade in children
Authors: Ivani G. , De Negri P. , Conio A. , Amati M. , Roero S. , Giannone S. , Lönnqvist P. A.
Published: March 2003

Background: Adding clonidine to weak ropivacaine solutions (<0.2%) could potentially enhance analgesia as well as further reduce the risk for unwanted motor blockade. The aim of the present study was to compare the postoperative pain‐relieving quality of a ropivacaine 0.1%‐clonidine mixture to that of plain ropivacaine 0.2% following caudal administration in children.

Methods: In a prospective, observer‐blinded fashion, 40 ASA 1 paediatric patients undergoing subumbilical surgery were randomly allocated to receive a caudal injection of either plain ropivacaine 0.2% (1 ml/kg) (R0.2) or a mixture of ropivacaine 0.1% with clonidine 2 μg/kg (1 ml/kg) (R0.1C). Objective pain scale score and need for supplemental analgesia were used to evaluate analgesia during the first 24 h postoperatively. Residual postoperative sedation was also assessed.

Results: A significantly higher number of patients in the R0.1C group (18/20) could be managed without supplemental analgesia during the first 24 h postoperatively compared to the R0.2 group (11/20) (P=0.034). Both the degree and the duration of postoperative sedation was similar in both groups. No signs of postoperative motor blockade were observed.

Conclusions: The combination of clonidine (2 μg/kg) and ropivacaine 0.1% is associated with an improved quality of postoperative analgesia compared to plain 0.2% ropivacaine. The improved analgesic quality of the clonidine‐ropivacaine mixture is achieved without causing any significant degree of postoperative sedation.
Comparison of hypotensive epidural anaesthesia and spinal anaesthesia on blood loss and coagulation during and after total hip arthroplasty Note
Authors: Niemi T. T. , Pitkänen M. , Syrjälä M. , Rosenberg P. H.
Published: March 2003

Background: Hypotensive epidural anaesthesia (HEA) is a technique for reducing peroperative blood loss by significantly lowering mean arterial pressure (MAP).

Methods: Thirty patients scheduled for primary total hip arthroplasty were given HEA (n=15) or spinal anaesthesia (SPA) (n=15) with bupivacaine in random order. The dose of bupivacaine was titrated to provide epidural blockade up to T1–T4 and spinal blockade at least to T10. Intravenous adrenaline infusion was adjusted to achieve a MAP of about 50–60 mmHg in the HEA group. During SPA MAP was maintained above 70 mmHg with ephedrine, as needed.

Results: Intraoperative blood loss (median and 25th and 75th percentiles) was 400 ml (163–575) in the HEA group and 900 ml (663–1100) in the SPA group (P<0.05). At 3 h postoperatively cumulative blood loss was still smaller in the HEA group (600 ml versus 1100 ml, P<0.05). The cumulative number of transfused packed red cell concentrate (PRC) units was smaller in the HEA group than in the SPA group during surgery and postoperatively. Prothrombin time value was smaller in the SPA than in the HEA group (69% versus 79%, P<0.05) at 3 h postoperatively. D‐dimer concentrations increased more in the SPA group at the end of the surgery and 3 h postoperatively (P<0.05).

Conclusions: HEA resulted in reduced blood loss due to hypotension and reduced number of transfused PRC units during total hip arthroplasty. Based on lower prothrombin time value and higher D‐dimer concentrations in the SPA group, the coagulation system might be better preserved during HEA than SPA.
Evaluation of three risk scores to predict postoperative nausea and vomiting
Authors: Eberhart L. H. J. , Högel J. , Seeling W. , Staack A. M. , Geldner G. , Georgieff M.
Published: March 2003

Background: So far there are three different scores to predict postoperative vomiting (PV: Apfel et al., 1998) or postoperative nausea and vomiting (PONV: Koivuranta et al., 1997; Palazzo and Evans, 1993). All three scores used logistic regression analysis to identify and create weights for the risk factors for PV or PONV. In short, these were sex, age, history of previous PONV, motion sickness, duration of anaesthesia, and use of postoperative opioids. However, an external evaluation and a comparison of these scores has not been performed so far.

Methods: Patients undergoing a variety of surgical procedures under general anaesthesia were studied prospectively. Preoperatively, they completed a questionnaire concerning potential risk factors for the occurrence of PV or PONV implemented in the three risk scores. Balanced anaesthesia (induction agent, non‐depolarising neuromuscular blocker, opioid, and inhalation agent in nitrous oxide/oxygen) was performed. No intravenous anaesthesia or any antiemetic prophylaxis was applied. Postoperatively, the patients were observed in the recovery room for the occurrence of PV and PONV and were visited twice on the ward within the 24‐h observation period. Both the patients and the nursing staff were asked whether PV or PONV was present. The severity of PONV was categorised using a standardised scoring algorithm. A total of 1444 patients was finally included into the analysis. Using information of the predicted risk for the individual patients and the actual occurrence of PV or PONV, Receiver Operator Characteristics (ROC‐curves) were drawn. The area under each ROC‐curve was calculated as a means of the predictive properties of each score and was compared for statistical differences.

Results: For prediction of PONV (any severity) the AUC‐values (AUC=area under the curve) and the corresponding 95%‐confidence intervals were: Apfel: 0.70 (0.67–0.72); Koivuranta: 0.71 (0.69–0.73); Palazzo: 0.68 (0.65–0.70). For prediction of PV: Apfel: 0.73 (0.71–0.75); Koivuranta: 0.73 (0.70–0.75); Palazzo: 0.68 (0.65–0.70). Thus, all three scores appeared to have a moderate accuracy as measured by the AUC. The score of Koivuranta predicts PONV (P=0.007) and also PV (P=0.002) significantly better than Palazzo’s score. Furthermore, for predicting of PV the score of Apfel was also superior to Palazzo’s score (P=0.005). All three scores predict PV with the same accuracy as PONV.

Conclusion: The occurrence of PV and PONV in patients undergoing surgery under balanced anaesthesia can be predicted with moderate but acceptable accuracy using one of the available risk scores, regardless of local surgical or anaesthesiological circumstances. For clinical practice, we recommend the score published by Koivuranta, since its calculation is very simple.