bluuebunny/crossref_metadata_2025_split huggingface dataset:
Excretion of lidocaine and bupivacaine in breast milk following epidural anesthesia for cesarean delivery
Authors: Ortega D. , Viviand X. , Lorec A. M. , Gamerre M. , Martin C. , Bruguerolle B. 
Published: March 2003

Background: There is a lack of information and knowledge about the practical importance of even low concentrations of the excretion of local anesthetics into breast milk, particularly concerning bupivacaine. The present work aims to confirm, under practical clinical conditions of admission of parturients, the passage of local anesthetics (lidocaine and bupivacaine) into breast milk after an epidural anesthesia.Methods: Twenty‐seven pregnant women admitted for cesarean delivery received epidural anesthesia with 0.5% bupivacaine and 2% lidocaine. Blood and milk samples were simultaneously collected at 2, 6 and 12 h after the beginning of the epidural infusion. Lidocaine, bupivacaine and its main metabolite, pipecolylxylidide (PPX), were determined in serum and milk by a gas‐liquid chromatographic technique. APGAR scores were systematically performed at delivery and a clinical examination was done 24 h after delivery.Results: Our data indicate that lidocaine and bupivacaine as well as PPX are excreted into breast milk. The milk/serum ratio based upon area under the curve values were 1.07±0.82, 0.34±0.24 and 1.37±0.61 mean±SD for lidocaine, bupivacaine and PPX, respectively. Most of the newborns had a maximal APGAR score. Our study does not reveal any adverse reactions related to the excretion of local anesthetics into breast milk.Conclusion: This study documents the magnitude of excreted lidocaine, bupivacaine and PPX in breast milk, and indicates that the use of both lidocaine and bupivacaine for epidural anaesthesia is safe with regard to breast‐feeding.
Comparison of transarterial and multiple nerve stimulation techniques for axillary block using a high dose of mepivacaine with adrenaline
Authors: Koscielniak‐Nielsen Z. J. , Rotbøll Nielsen P. , Loumann Nielsen S. , Gardi T. , Hermann C. 
Published: March 2003

Background: High‐dose transarterial (TA) technique results in high effectiveness of the axillary block. The technique is fast and simple, but does not produce a satisfactory success rate when using the manufacturer’s recommended dose of mepivacaine. The multiple nerve stimulation (MNS) technique requires more time and experience. This double‐blind study compared effectiveness, safety and the time used to obtain an effective analgesia in 101 patients, having an axillary block by either TA or MNS techniques.Methods: Mepivacaine with adrenaline (MEPA), 850 mg, was used for the initial block. Five millilitres of 1% solution was injected subcutaneously. In the TA group, 20 mL of 2% solution was injected deep to, and 20 mL superficial to the axillary artery. In the MNS group, four terminal motor nerves were electrolocated in the axilla, and injected with 10 mL each. Analgesia was assessed every 10 min and, when needed, supplemented after 30 min. The block was effective when analgesia was present in all sensory nerve areas distal to the elbow.Results: The MNS group required median 11 min for block performance compared with 8 min for the TA group (P<0.001). Latency of the initial block was shorter and the frequency of supplemental analgesia lower in the MNS group (median 10 min and 6%) than in the TA group (30 min and 36%, respectively), P<0.001. All incomplete blocks were successfully supplemented. However, the total time to obtain an effective block was shorter in the MNS group (23 min) than in the TA group (37 min), P<0.001. Two patients in each group had signs and symptoms of systemic toxicity, the most serious being atrial fibrillation and temporary loss of consciousness in a cardiovascularly medicated patient. The local adverse effects (intravascular injections and haematomas) were fewer in the MNS group, P<0.001.Conclusion: The MNS technique of axillary block by four injections of 10 mL of 2% MEPA produces faster and more extensive block than the TA technique by two injections of 20 mL. Therefore, the MNS technique requires fewer supplementary blocks and results in faster patient readiness for surgery. However, high doses of MEPA may result in dangerous systemic toxic reactions.
Responses to propofol in the pulmonary vascular bed of the rat
Authors: Kaye A. , Anwar M. , Banister R. , Feng C. , Turner K. , Kadowitz P. , Nossaman B. 
Published: March 2003

Background: Although a great deal is known about responses to propofol, controversy remains about its mechanism of action. The present study was undertaken to investigate the direct effects of 2,6‐diisopropyl phenol, disodium edetate, and its intralipid emulsion in the rat pulmonary vascular bed and to better understand the mechanisms involved in propofol‐mediated responses.Methods: The effects of Nω‐l‐nitro‐l‐arginine benzyl ester (L‐NABE), an inhibitor of nitric oxide synthase, of the cyclooxygenase blocker, meclofenamate, and the K+ATP channel antagonist, U‐37883A, an ATP‐sensitive potassium channel antagonist, on responses to propofol, acetylcholine, nitroglycerin, and isoproterenol were investigated in the isolated blood‐perfused rat lung under low tone and high steady‐state tone.Results: Propofol produced a dose‐dependent decrease in pulmonary arterial perfusion pressure. L‐NABE significantly reduced vasodilator responses to acetylcholine, whereas the nitric oxide synthase inhibitor had no significant effect on responses to propofol. Meclofenamate significantly reduced vasodilator responses to arachidonic acid without effecting responses to propofol. Responses to propofol were not significantly changed in the presence of U‐37883A, whereas U‐37883A reduced vasodilator responses to levcromakalim. Additionally, 2,6‐diisopropylphenol in a pure preparation as well as an intralipid preparation similar to propofol emulsion had no significant effect while disodium edetate had a dose‐dependent depressor effect under high steady‐state tone.Conclusion: Propofol has significant vasodilator activity in the pulmonary vascular bed of the rat but responses to propofol are not mediated or modulated by the release of nitric oxide, opening of K+ATP channels, or the release of vasodilator cyclooxygenase products.
The role of arterial and venous pressure for volume regulation of an organ enclosed in a rigid compartment with application to the injured brain
Authors: Kongstad L. , Grände P. O. 
Published: March 2003

Background: Treatment of increased intracranial pressure often includes an active change in arterial and venous pressure, sometimes with draining of cerebrospinal fluid. We evaluated tissue and perfusion pressure during corresponding interventions in an organ enclosed in a rigid compartment with capillaries permeable for electrolytes and impaired autoregulation, conditions comparable to those present in the injured brain.Method: An isolated cat skeletal muscle enclosed in a closed fluid‐filled plethysmograph served as a model for the injured brain surrounded by cerebrospinal fluid and the cranium. Tissue pressure and blood flow were measured during variation in arterial and venous pressures and in intraplethysmographic fluid volume. Autoregulation was depressed by papaverine.Results: 1) Tissue pressure was not influenced by the venous pressure when this was below the tissue pressure, hereby generating venous collapse and a venous outflow resistance. When venous pressure was higher than the tissue pressure (no venous outflow resistance), these two parameters changed in parallel. 2) A change in arterial pressure induced a similar large change in tissue pressure at steady state, whereas blood flow remained unchanged. 3) Variation in tissue pressure induced by a change in the intraplethysmographic fluid volume was transient.Conclusions: If applicable to the injured brain, the results indicate that 1) a venous pressure change has a small influence on the intracranial pressure when a venous outflow resistance is present, 2) brain oedema can be reduced by lowering of the arterial inflow pressure, and blood flow will be maintained, 3) the decrease in intracranial pressure obtained by draining cerebrospinal fluid will be transient.
Interaction between fluconazole and midazolam in intensive care patients
Authors: Ahonen J. , Olkkola K. T. , Takala A. , Neuvonen P. J. 
Published: March 2003

Background: Midazolam is used for sedation of intensive care unit (ICU) patients and it is extensively metabolised by CYP3A4 enzymes. The antimycotic fluconazole is often used in these patients as well and has been shown to inhibit CYP3A4‐mediated drug metabolism.Methods: In a study of the effect of fluconazole on midazolam in the ICU, ten mechanically ventilated patients (age 29 to 61 years, 8 male) sedated with a stable midazolam infusion were enrolled after a decision to start fluconazole treatment. Fluconazole was infused for 30 min at intervals of 24 h, with an initial dose of 400 mg and following doses of 200 mg. The midazolam infusion rate remained unchanged during the study period of 48 h. Plasma concentrations of midazolam, α‐hydroxymidazolam, and α‐hydroxymidazolam conjugate were determined at baseline, and at 6, 12, 18, 24, 36, and at 48 h thereafter.Results: Concentrations of midazolam were significantly increased (range 0 to 4‐fold, P<0.05) after start of fluconazole treatment. These increases were most marked in patients with renal failure. During the study period, the ratio of α‐hydroxymidazolam to midazolam decreased progressively (P<0.05).Conclusion: In ICU patients receiving fluconazole, reduction of midazolam infusion rate should be considered if the degree of sedation is found to be increasing.
Splanchnic circulation is maintained during passive hyperventilation in orthotopic liver recipients
Authors: Krenn C. G. , Pernerstorfer T. , Pokorny H. , Metnitz P. G. H. , Steltzer H. 
Published: March 2003

Background: Mechanical hyperventilation is an established treatment to reduce brain edema and intracranial pressure in patients with encephalopathia caused by acute liver failure. Hyperventilation and ensuing hypocarbia may also affect central and systemic circulation and thereby influence graft performance in patients following orthotopic liver transplantation (OLT).Methods: We measured the effects of normocapnia and hypocapnia on systemic hemodynamics, gastric tonometry, as a marker of splanchnic oxygenation, and the indocyanine green kinetic, as a global marker of graft function, in humans post OLT.Results: Hyperventilation was performed to a paCO2 of 4.2±0.4 kPa (31±3.4 mm Hg) for about 1 h in 14 liver transplant recipients. Systemic hemodynamics as well as indices of splanchnic oxygenation and indocyanine green kinetics remained statistically unchanged.Conclusion: We did not observe any statistically significant circulatory effects or changes in indocyanine green kinetics in liver transplant recipients in the immediate OLT postoperative period caused by short‐term mechanical hyperventilation.
EEG bispectral index monitoring in sevoflurane or propofol anaesthesia: analysis of direct costs and immediate recovery
Authors: Yli‐Hankala A. , Vakkuri A. , Annila P. , Korttila K. 
Published: March 2003

Background: Recent studies have suggested that electroencephalogram (EEG) bispectral index (BIS) monitoring can improve recovery after anaesthesia and save money by shortening patients’ postoperative stay. We wanted to evaluate the direct costs of BIS monitoring and to measure immediate recovery after anaesthesia in patients with or without BIS monitoring.Methods: Eighty patients undergoing gynaecological surgery were studied. At first, 40 patients were randomized to receive either propofol or sevoflurane anaesthesia. In these patients, BIS was collected but the information was not displayed. Thereafter, the anaesthesiologists were trained to follow and understand the BIS information, and 40 patients were anaesthetized with aid of the monitoring. Recovery times were measured by a study coordinator. Drug consumption was calculated.Results: BIS monitoring improved the immediate recovery after propofol anaesthesia, while no differences were seen in patients receiving sevoflurane. The consumption of both propofol and sevoflurane decreased significantly (29% and 40%, respectively). BIS monitoring increased direct costs in these patients; the break‐even times (704 min for propofol and 282 min for sevoflurane) were not reached.Conclusion: BIS monitoring decreased the consumption of both propofol and sevoflurane and hastened the immediate recovery after propofol anaesthesia. Detailed cost analysis showed that the monitoring increased direct costs of anaesthesia treatment in these patients, mainly due to the price of special EEG electrodes used for relatively short anaesthesias.
A comparison of train‐of‐four monitoring: Mechanomyography at the thumb vs acceleromyographyat the big toe
Authors: Heier T. , Hetland S. 
Published: March 2003

Background: It is not known if the information on neuromuscular function obtained from the hand is interchangeable with that of the foot. In the present study the agreement of thumb mechanomyography with acceleromyography of the big toe was studied.Methods: Ten healthy patients scheduled for oral surgery were studied. Anaesthesia was induced with fentanyl 2 μg kg−1 and propofol 2 mg kg−1, and maintained with propofol 100–175 μg kg−1 min−1, nitrous oxide 60–70%, and fentanyl 1–2 μg kg−1 h−1. Vecuronium 0.1 mg kg−1 was used for muscle relaxation. Mechanomyography (MMG) of the thumb (Myograph 2000) and acceleromyography (AMG) of the big toe (TOF‐Guard) were recorded simultaneously in all patients, and onset, period of no‐twitch response, duration of action, and spontaneous recovery time obtained from both muscle groups. The agreement between methods was tested by calculation of bias and limits of agreement.Results: The onset time and duration of action were significantly shorter (87 s vs 154 s, and 35 min vs 38 min, respectively), and the spontaneous recovery time significantly longer in the thumb than in the big toe (32 min vs 19 min). Period of no‐twitch response was not significantly different in the two muscle groups. Limits of agreement (thumb big toe) were −21 to −113 s, −7 to 1 min, and −9 to 35 min, for onset time, duration of action, and spontaneous recovery time, respectively.Conclusion: We conclude that clinically acceptable agreement between thumb mechanomyography and big toe acceleromyography was found for the period of no‐twitch response, suggesting that the timing of supplemental doses of vecuronium can be guided by AMG at the big toe. However, the spontaneous recovery time agreement (to TOF ratio=0.75) between the thumb and the big toe was poor.
Chronic pain after thoracic surgery: a follow‐up study
Authors: Perttunen K. , Tasmuth T. , Kalso E. 
Published: March 2003

Background: The incidence of long‐term post‐thoracotomy pain is reported to be up to 67%. A relationship between the severity of acute postoperative pain and the development of chronic post‐thoracotomy pain has been suggested.Methods: Patients scheduled for elective thoracotomy were interviewed before and one week after surgery to find out if they had pain before surgery and how much pain they experienced postoperatively. The amount of analgesics the patients were given were registered during the first 5 postoperative days. The patients were interviewed by letter 3, 6 and 12 months after surgery to find out if they still had pain due to surgery and to what extent this pain interfered with their daily activities.Results: One hundred and ten patients entered the study. Information about the complete study period was obtained from 67 patients. The incidence of chronic post‐thoracotomy pain was 80% at 3 months, 75% at 6 months and 61% one year after surgery. The incidence of severe pain was 3–5%. Chronic post‐thoracotomy pain interfered with the patient’s normal daily life in more than half of the patients. High consumption of analgesics during the first postoperative week was associated with a higher risk of chronic post‐thoracotomy pain.Conclusion: A significant proportion of patients undergoing thoracotomies will suffer from chronic pain. Surgeons and anaesthetists should be aware of this fact and they should look for effective means of preventing and treating this pain syndrome.
Epidural ropivacaine 7.5 mg/ml for elective Caesarean section: A double‐blind comparison of efficacy and tolerability with bupivacaine 5 mg/ml
Authors: Bjørnestad E. , Smedvig J. P. , Bjerkreim T. , Narverud G. , Kollerøs D. , Bergheim R. 
Published: March 2003

Background: Ropivacaine is a new local anaesthetic drug known to be less cardiotoxic than bupivacaine. The aims of this comparative study with bupivacaine were to evalute efficacy, safety and tolerability for the mother and the neonate when using ropivacaine 7.5 mg/ml for epidural anaesthesia for elective Caesarean section.Methods: In a double‐blind, multicentre trial the patients were randomised to receive 20 ml of either ropivacaine 7.5 mg/ml or bupivacaine 5 mg/ml. The quality of the peroperative analgesia and abdominal muscle relaxation as well as tolerability and safety in both the mother and the neonate were evaluated.Results: A total of 122 patients were evaluated for efficacy and tolerability. There were no significant differences in the onset time and the extent of the sensory spread or motor block. The peroperative quality of anaesthesia and muscle relaxation was similar in both groups. No significant side effects were observed, except for a more profound drop in systolic blood pressure in the ropivacaine group. The anaesthetics were well tolerated by the neonate in both groups, evaluated by Apgar and NACS scores.Conclusion: Ropivacaine 7.5 mg/ml administered epidurally resulted in equally effective anaesthesia for Caesarean section as bupivacaine 5 mg/ml. Because of the lower cardiotoxicity of ropivacaine, the new amide has a potential in replacing bupivacaine when used epidurally for Caesarean section.
Block of the brachial plexus branches by the humeral route. A prospective study in 503 ambulatory patients. Proposal of a nerve‐blocking sequence
Authors: Gaertner E. , Kern O. , Mahoudeau G. , Freys G. , Golfetto T. , Calon B. 
Published: March 2003

Background: Brachial plexus is usually approached by the supraclavicular or axillary route. A technique for selective blockade of the branches of the plexus at the humeral canal using electrolocation has recently been proposed. The aim of the present study was to assess the feasibility of this technique in the ambulatory patient and to determine the optimal sequence of nerve‐blocking.Methods: The nerves originating from the brachial plexus were located in the humeral canal, at the junction of the proximal and the middle third of the arm, with a stimulator and blocked using either lidocaine or a mixture of lidocaine and bupivacaine, depending on the anticipated duration of surgery. The minimal stimulating intensity eliciting an adequate response, type of local anaesthetic and injected volume, and time of onset of surgical anaesthesia were collected.Results: The study included 503 consecutive ambulatory patients due to undergo surgery of the elbow, wrist or hand in one year. Suitable anaesthesia was obtained with the humeral blockade in 82.1% of cases. In the remaining 17.9%, an additional block at the elbow was required, mainly for ulnar and median nerves. The onset times of sensory blocks were the longest for the median nerve, similar for the radial and ulnar nerves, shorter for the musculocutaneous nerve and the shortest for the medial brachial and antebrachial cutaneous nerves. The difference was more significant with the lidocaine‐bupivacaine mixture, than with lidocaine alone (P<0.001 vs P<0.05, respectively). The onset times of motor blocks were the longest for the median nerve (P<0.05) and the shortest for the musculocutaneous nerve (P<0.001). Neither nervous nor vascular complications occurred.Conclusion: This study shows that the nerve block at the humeral canal is an efficient and safe technique. Considering the onset times of nerve blocks, the following sequence for blockade can be recommended: median, ulnar, radial, musculocutaneous, medial (brachial and antebrachial) cutaneous nerves. The selective blockade of the main nerves of the upper limb at the humeral canal can be recommended for surgery of the forearm and the hand in the ambulatory patient.
An alternative method to intubate with laryngeal mask and see‐through‐bougie
Authors: Hammarskjöld F. , Lindskog G. , Blomqvist P. 
Published: March 2003

Background: Different ways of managing the difficult airway is an important issue for the anaesthetist. We have investigated a technique with a see‐through‐bougie and laryngeal mask for intubation.Methods: We report our experience with intubation of 30 patients using a see‐through‐bougie guided through a laryngeal mask with a fibreoptic bronchoscope. The bougie is then used as a guidance for a tracheal tube.Results: In 29 of the 30 investigated patients, this method could be used. In one patient the method had to be abandoned because of a tortuous trachea. Seventeen patients were intubated within 2 min, 11 between 2 and 5 min and 1 required 10 min. The time was mainly dependent on the endoscopic experience of the anaesthetist. No patient sustained arterial desaturation.Conclusion: We conclude that intubation using a see‐through‐bougie and a laryngeal mask is a valuable method in the difficult intubation situation, when a temporary airway can be achieved with laryngeal mask, since it permits continuous ventilation and visual control throughout the procedure.
Intrathecal co‐administration of NMDA antagonist and NK‐1 antagonist reduces MAC of isoflurane in rats
Authors: Ishizaki K. , Sasaki M. , Karasawa S. , Obata H. , Nara T. , Goto F. 
Published: March 2003

Background: Intravenous administration of N‐methyl‐D‐aspartate (NMDA) receptor antagonists and α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) receptor antagonists reportedly reduce the minimum alveolar anaesthetic concentration (MAC) for inhalation anaesthetics. If pain perception can be prevented by the intrathecal administration of antinociceptive receptor antagonists, these agents may reduce the requirements for inhalation anaesthetics. We studied the effect of intrathecal administration of an AMPA/kainate receptor antagonist, a metabotropic glutamate (mGlu) receptor antagonist and co‐administration of NMDA and a neurokinin‐1(NK‐1) receptor antagonist drugs at low doses on the MAC.Methods: After Wistar rats (n=36) were fitted with indwelling intrathecal catheters, the MAC of isoflurane was determined following intrathecal administration of a non‐NMDA receptor antagonist (CNQX) at 10 μg, a mGlu receptor antagonist (AP3) at 10 μg, or a combination of NMDA receptor antagonist (APV) at 0.01 μg to 1 μg with NK‐1 receptor antagonist (CP96345, CP) at 0.1 μg to 10 μg. Subsequently, a reversal dose of intrathecal NMDA with substance P (SP) was administered, and the MAC of isoflurane was redetermined. Conscious rats (n=15) were also examined for the presence of locomotor dysfunction following the intrathecal co‐administration of APV and CP.Results: Neither CNQX nor AP3 reduced the MAC of isoflurane. APV at 0.01 μg plus CP at 1 μg, as well as APV at 0.1 μg plus CP at 10 μg, reduced the MAC of isoflurane, with respective reductions of 7.6% and 14%; (P<0.05). Co‐administration of NMDA plus SP reversed the decrease in the MAC of isoflurane. Locomotive activity was not changed.Conclusions: The NMDA receptor and the NK‐1 receptor are important determinants of the MAC of isoflurane, exerting this influence by inhibition of pain transmission in the spinal cord, while mGlu and AMPA receptors have no effect on the MAC of isoflurane.