bluuebunny/crossref_metadata_2025_split huggingface dataset:
Weight gain during pregnancy does not influence the spread of spinal analgesia in the term parturient
Authors: EKELØF N. P. , JENSEN E. , POULSEN J. , REINSTRUP P. 
Published: January 2009

Background: It is still controversial whether the spread of spinal anaesthesia in pregnancy is influenced by particular physique. Investigation was based on a clinical observation that parturients with a pronounced “pregnant” physique, e.g. generalised oedema and heavy abdomen, tended to develop more cephalad sensory blockades than parturients without these physical signs. Using weight gain during pregnancy as a measure for the physique at term, we aimed to determine whether this parameter influences the distribution of analgesia after subarachnoidal injection of plain bupivacaine.Methods: Thirty women presenting for elective Caesarean section were studied. All the women received 13.5 mg plain bupivacaine via subarachnoid injection at the L2_3 interspace. Thirty minutes after the injection, while the women were in the supine position with a left lateral tilt on a horizontal operating table, the maximum cephalad extent of sensory analgesia (loss of sensation to sharpness of pinprick) was determined.Results: Neither weight gain during pregnancy (6–22 kg, range), height (152–185 cm), weight (56–98 kg) nor body‐mass index (20.2–31.8 kg/m2) correlated with the cephalad spread of sensory blockade.Conclusion: In parturients, weight gain during pregnancy, height, weight and body‐mass index did not influence the extent of sensory analgesia after subarachnoidal administration of plain bupivacaine.
Pharmacodynamic modelling of the analgesic effects of piritramide in postoperative patients
Authors: KIETZMANN D. , BOUILLON T. , HAMM C. , SCHWABE K. , SCHENK H. , GUNDERT‐REMY U. , KETTLER D. 
Published: January 2009

Background:The concentration‐effect relationship of piritramide, a synthetic opioid analgesic predominantly used for postoperative analgesia and analgosedation, has not been reported so far.Methods:Twenty‐four patients of both genders aged 58.1 (11.7) yr (mean (SD)) received inhalational anaesthesia for abdominal surgery. Postoperative pain was assessed with a visual analogue scale (VAS). Analgesia was provided with piritramide, infused at a rate of 7 μg kg‐1min‐1until analgesia was considered sufficient (VAS<25) or up to a maximum dose of 0.2 mg/kg. The plasma concentrations of piritramide were determined by gas chromatography. An inhibitory fractional sigmoid Emax‐model was used to describe the relation between effect site concentration and perceived pain.Results:The equilibration half‐life between plasma and effect site concentrations (T1/2(keo) was 16.8 min (median; range: 4.4–41.6 min). The steady‐state plasma concentration required to produce 50% of maximum analgesia (EC50) was 12.1 ng/ml (range: 2.9–29.8 ng/ml) and correlated with initial pain intensity. The slope factor γ was 1.9 (range: 0.5–6.1) and increased with age. Clinically relevant respiratory depression did not occur. Due to the relatively large equilibration half‐life of the effect compartment, the context‐sensitive half‐time of the effect site concentrations after short‐time administration (<2 h) clearly exceeded those of alfentanil, sufentanil, and fentanyl.Conclusions:The analgesic effect of piritramide was adequately described by an inhibitory fractional Emax‐model. In order to overcome the pronounced hysteresis, piritramide should initially be administered as an intravenous bolus of at least 5 mg.
Interaction between sufentanil and U‐50488H with respect to antinociception and respiratory depression in rats
Authors: VERBORGH C. M. L. , CAMU F. , MEERT T. F. 
Published: January 2009

Background:Opiate receptors have been argued to differentially regulate analgesia and respiratory depression. In order to validate possible interactions between the opiate mu‐ and kappa‐receptors, interactions between sufentanil and U‐50488H were studied in rats.Methods:Rats equipped with an arterial catheter were tested in the tail flick latency (TFL) test after intravenous treatment with sufentanil (a mu‐agonist), U‐50488H a kappa‐agonist) or fixed ratio combinations of both drugs. Simultaneously, respiratory changes were monitored by blood gas analysis.Results:The ED50s of sufentanil for a TFL >6.0 and <10.0 s were 0.0002 and 0.00059 mg/kg. For U‐50488H the corresponding values were 1.53 and 8.11 mg/kg. Using a fixed dose ratio of 1/10000, an additivity was demonstrated between sufentanil and U‐50488H in terms of antinociception. With regard to respiratory parameters, PaCO2significantly increased after all doses of sufentanil early after treatment. At the higher doses tested, there was also a decrease in PaO2and O2saturation. For U‐50488H only the highest doses resulted in an early and small shift in PaCO2. The combination of sufentanil/U‐50488H resulted in only a small increase in PaCO2at the highest dose regimen tested.Conclusion:The results presented here demonstrate that drug mixtures of sufentanil and U‐50488H can be additive with respect to antinociception with additionally less risk for respiratory side‐effects, as compared with sufentanil alone. Therefore, a combination of mu‐ and kappa‐opiate receptor agonists might be more beneficial than each agent alone.
Minimum alveolar concentration of sevoflurane for tracheal extubation in children
Authors: HIGUCHI H. , URA T. , TAODA M. , TANAKA K. , SATOH T. 
Published: January 2009

Background: One advantage of tracheal extubation during deep anaesthesia is that respiratory complications are reduced. Sevoflurane is a suitable anaesthetic agent for children. This study was conducted to determine the minimum alveolar concentration of sevoflurane required to prevent cough or movement during and after tracheal extubation (MACextubation).Methods: We studied 30 nonpremedicated children, aged 2–10 yr, undergoing plastic surgery. They were allocated randomly to five groups (end‐tidal sevoflurane concentrations: 2.0, 2.5, 3.0, 3.5, 4.0%). After surgery, 60% nitrous oxide was discontinued and the target concentration of sevoflurane was maintained for at least 10 min in 100% oxygen, then the trachea was extubated to determine MACextubation. Logistic regression was used to estimate MACextubation. of sevoflurane.Results: MACextubation. was 2.3 (0.2; standard error)% (95% confidence limits: 1.2% and 2.7%).Conclusions: Tracheal extubation in 50% of anaesthetized children age 2–10 yr may be accomplished without coughing or moving at 2.3% end‐tidal concentration of sevoflurane.
Intravenous dolasetron and ondansetron in prevention of postoperative nausea and vomiting: a multicenter, double‐blind, placebo‐controlled study
Authors: KORTTILA K. , CLERGUE F. , LEESER J. , FEISS P. , OLTHOFF D. , PAYEUR‐MICHEL C. , WESSEL P. , NAVE S. , HAHNE W. , BROWN R. 
Published: January 2009

Background: Intravenous dolasetron mesilate has shown efficacy in the prevention of postoperative nausea and vomiting (PONV) when administered as a single dose prior to emergence from anesthesia. This trial compared intravenous dolasetron and ondansetron for the prevention of PONV when administered at induction of anesthesia.Methods: This double‐blind, placebo‐controlled, multicenter trial randomized patients to one of four single IV treatments: placebo, 25 or 50 mg dolasetron, or 4 mg ondansetron. Efficacy was measured by complete response (0 emetic episodes and no rescue medication), nausea severity and patient satisfaction as measured on a visual analog scale (VAS), investigator's rating of nausea severity, and total response (complete response with no nausea [≤ mm VAS]).Results: 514 patients at 24 sites were evaluated for efficacy. The 50 mg dolasetron and 4 mg ondansetron doses were statistically equivalent, and superior to placebo, for all efficacy measures. Complete response rates were 49%, 51%, 71% and 64% for placebo, 25 and 50 mg dolasetron, and ondansetron, respectively. Dolasetron 50 mg was statistically superior to 25 mg dolasetron for complete response, total response, VAS maximum nausea, time to first emetic episode, and patient satisfaction. The majority of adverse events were of mild‐to‐moderate intensity. Headache was the most frequently reported treatment‐related adverse event with a 3%‐5% incidence across treatments.Conclusion: When given at induction of anesthesia, 50 mg intravenous dolasetron is equivalent to 4 mg ondansetron and superior to 25 mg dolasetron and placebo for the prevention of PONV. All treatments were safely administered and well tolerated.
Nitrous oxide reduces inspired oxygen fraction but does not compromise circulation and oxygenation during hemodilution in pigs
Authors: SCHOU H. , SÁ V. PEREZ DE , ROSCHER R. , LARSSON A. 
Published: January 2009

Background: The use of nitrous oxide (N2O) during hemodilution has been questioned. Nitrous oxide reduces the inspired oxygen fraction (F1O2), depresses myocardial function and may reduce cardiac output (CO) and systemic oxygen delivery (DO2SY). The aim of this study was to evaluate the importance of the effects of nitrous oxide on systemic and myocardial circulation and oxygenation during extreme, acute, normovolemic hemodilution.Methods: Ten midazolam‐fentanyl‐pancuronium anesthetized pigs were exposed to 65% N2O before and after extreme isovole‐mic hemodilution (hematocrit 33±1% and 10±1%, respectively). Systemic and myocardial hemodynamics, oxygen delivery and consumption and blood lactate were measured before (at FrO2 1.0 and 0.35) and during N2O exposure.Results: Hemodilution caused an increase in CO from 137±43 to 229±32 ml kg‐1 min‐1 (P< 0.01), a decrease in systemic vascular resistance (from 42±14 to 20±4 mmHg L‐1 min‐1, P < 0.05), a decrease in mean arterial blood pressure (from 119±19 to 100±26 mmHg, P<0.05) and a decrease in DO2SY from 21.1 ±6.9 to 13.7±2.1 ml kg‐1 min‐1 (P < 0.01). Cardiac venous blood flow increased by 135% (P < 0.01) and cardiac venous saturation from 25±6 to 41±5% (P < 0.05). After hemodilution, changing FIO2 from 1.0 to 0.35 reduced arterial blood oxygen content from 59.4±3.7 to 52.3±5.1 ml L‐1 (P < 0.01), mixed venous saturation (SvO2) from 75±9 to 47±7% (P < 0.05) and DO2SY from 13.7±2.1 to 11.9+2.3 ml kg‐1 ‐ min‐1 (P < 0.05). Dissolved oxygen at F1O2=1.0 and F1O2=0.35 constituted 25.4±3.1% and 10.1 ±1.5%, respectively, of systemic oxygen delivery after hemodilution, compared with 10.7±1.2% and 3.9±0.5% before hemodilution (P < 0.01). Left ventricular oxygen delivery and consumption were unchanged. Exposure to N2O did not affect mean arterial blood pressure or systemic vascular resistance before or after hemodilution. After hemodilution during N2O‐exposure, CO and DO2SY decreased by 9% (P < 0.01 and P < 0.05, respectively), but no changes in SvO2, systemic oxygen uptake or arterial lactate were observed. The effect of N2O on myocardial oxygenation was similar before and after hemodilution; cardiac venous blood flow, left ventricular oxygen delivery and uptake decreased, but no animals showed left ventricular lactate production.Conclusion: Nitrous oxide did not compromise systemic and myocardial circulation and oxygenation during acute normovolemic hemodilution in pigs. Possible adverse effects from the use of nitrous oxide during hemodilution seem to be related to a reduced FIO2, reducing the safety margin for systemic oxygen delivery.
Effects of halothane and isoflurane on left ventricular diastolic function during surgical stress in patients with coronary artery disease
Authors: HOULTZ E. , CAIDAHL K. , ADIN C. , GUSTAVSSON T. , RICKSTEN S.‐E. 
Published: January 2009

Background: The effects of inhalation anesthetics on left ventricular (LV) systolic function are well documented, while the effects of these agents on LV diastolic function have mainly been evaluated in animal studies, with conflicting results.Methods: We investigated the effects of halothane and isoflurane, when used to control the stress response to sternotomy in 33 patients with coronary artery disease (CAD). LV early diastolic relaxation and end‐diastolic stiffness were evaluated from mitral Doppler flow profiles, transesophageal two‐dimensional echocardiography, and central hemodynamic measurements. Measurements were performed a) after induction of anesthesia, b) after volume loading, c) prior to surgery and d) during surgery, 10 min after introduction of the inhalation anesthetic. The effects of the anesthetics on Doppler indices reflecting early diastolic relaxation, and on the left ventricular end‐diastolic pressure‐area (LVED P/A) relationship, were studied.Results: When data obtained during surgical stress were compared to the control situation, we found an increase in the LV filling pressures in both groups, while only the isoflurane group showed an increase in heart rate. An increase in end‐systolic LV area and decreased fractional area change was present in the halothane group, while an increase in LV end‐diastolic area, and similar changes in the mitral Doppler indices (decreases of deceleration rate and time of early diastolic filling), indicating an impairment of early diastolic relaxation, was present in both groups. Isoflurane induced a displacement of the LVED P/A relationship leftwards from the baseline LVED P/A curve.Conclusion: Both halothane and isoflurane impair early diastolic relaxation in patients with CAD, when used to control intraoperative surgical stress. In contrast to halothane, isoflurane induced a change in the LVED P/A relationship, suggestive of an increased LVED stiffness.
α1‐adrenoceptor stimulation is able to reverse halothaneinduced cardiac depression in isolated rat hearts
Authors: OKUYAMA T. , HOKA S. , OKAMOTO H. , KAWASAKI T. , YAMAURA K. , TAKAHASHI S. 
Published: January 2009

Background:Stimulation of myocardial α1‐adrenoceptors has been shown to exert positive inotropic effects through a cyclic AMP‐independent mechanism. The purpose of this study was to examine if α1‐adrenoceptor stimulation is able to attenuate myocardial depression produced by exposure to halothane, and to test if α1‐adrenoceptor stimulation alters myocardial oxygen supply‐demand balance in hearts exposed to halothane.Methods:The effects of phenylephrine were examined in 7 isolated perfused rat hearts. Variables measured were: heart rate, isovolumetric peak left ventricular pressure (LVP), LV dP/dt, coronary arterial flow, myocardial O2delivery (DO2), myocardial O2consumption (MVO2) and the ratio of DO2/MVO2. Each heart was exposed to phenylephrine cumulatively 0.1 μM, 0.3 μM, 1 μM and 3 μM under the administration of 1% halothane in the presence of propranolol 1μM.Results:Halothane 1% decreased the heart rate by 9±3%, LVP by 37±3%, and LV dP/dt by 35±2%. Phenylephrine restored these decreases to the baseline levels. Phenylephrine maintained or further enhanced the reductions in coronary flow and DO2produced by halothane, resulting in a decrease in the DO2/ MVO2ratio.Conclusion:α1adrenoceptor stimulation is capable of restoring direct cardiac depressant effects of halothane with a possible impairment of the oxygen supply‐demand balance.
Does propofol reduce vomiting after strabismus surgery in children?
Authors: HAMUNEN K. , VAALAMO M. O. , MAUNUKSELA E.‐L. 
Published: January 2009

Background: Previous studies have indicated that propofol anaesthesia may reduce the incidence of postoperative nausea and vomiting after strabismus surgery in children. This study was designed to investigate the incidence of vomiting after strabismus surgery at two different levels of propofol anaesthesia compared to thiopental/isoflurane anaesthesia.Methods: Ninety ASA class I or II children, aged 5–14 yrs were randomly assigned to one of three groups: Group T/I (n=30) induction with 5 mg kg‐1 of thiopental and maintenance with isoflurane, group P5 (n=31) induction with propofol 2 mg kg‐1, maintenance with propofol infusion 5 mg kg‐1 h‐1 or group P10 (n=29) induction with propofol 2 mg kg‐1, maintenance with propofol 10 mg kg‐1 h_I. All received glycopyrrolate, vecuronium, fentanyl and controlled ventilation with O2/N2O 30/ 70. Ketorolac i.v. was given to prevent postoperative pain. If additional analgesia was needed, ibuprofen/acetaminophen or buprenorphine was given according to clinical need.Results: There were no differences between study groups with respect to age, weight, history of previous anaesthesia or emesis after previous anaesthesia, duration of anaesthesia, surgery or sleep after anaesthesia, or number of muscles operated. The incidence of vomiting was 37%, 29% and 28% in groups T/I, P5 and P10, respectively. There were no statistically significant differences between the three groups in the incidence of vomiting. The median age of patients who vomited was 7.5 (range 5.0–13.7) yrs while the median age of the patients who did not vomit was 9.1 (range 5.0–14.0) yrs (P < 0.01).Conclusion: In the present study, propofol anaesthesia compared to thiopental/isoflurane anaesthesia did not reduce the incidence of vomiting following strabismus surgery in children.
Intubating conditions provided by propofol and alfentanil ‐ acceptable, but not ideal
Authors: HARSTEN A. , GILLBERG L. 
Published: January 2009

Background: The use of muscle relaxants to facilitate intubation is associated with several side effects regardless of whether depolarizing or non‐depolarizing drugs are used. In the present study we compared the intubating conditions, haemodynamic responses and changes in oxygen saturation following induction with alfentanil and propofol or alfentanil, thiopental and suxamethonium.Methods: Eighty patients (ASA I or II) were in a double‐blind manner assigned to receive either of the two induction methods. Intubating conditions were assessed on the basis of jaw relaxation, ease of insertion of the endotracheal tube and coughing on intubation. Heart rate, systolic arterial pressure and oxygen saturation were monitored throughout the procedure.Results: The use of alfentanil and propofol resulted in significantly lower scored intubation points. Systolic arterial pressure decreased and heart rate increased significantly in the alfentanil‐thiopental‐suxamethonium group as compared to the alfentanil‐propofol group. There were no significant changes in oxygen saturation.Conclusion: The results show that propofol and alfentanil in combination provides haemodynamic stability and unaltered oxygen saturation but less optimal intubating conditions.
Recovery characteristics of sevoflurane‐ or propofol‐based anaesthesia for day‐care surgery
Authors: RÆDER J. , GUPTA A. , PEDERSEN F. M. 
Published: January 2009

Background: Sevoflurane has a low blood‐gas partition coefficient resulting in a rapid recovery. Few studies have examined the maintenance and recovery characteristics of sevoflurane compared with propofol in a standardized outpatient population.Methods: The study was a multicentre study performed in 10 centres. One hundred and sixty‐nine elective outpatients due for knee‐arthroscopy received 100 mg diclofenac rectally as pain prophylaxis prior to induction of general anaesthesia with fentanyl 1.0–1.5 μg/kg+propofol 2.0–2.5 mg/kg iv. Anaesthesia was maintained with 60% nitrous oxide in oxygen through a laryngeal mask and continuous administration of either: sevoflurane (group S) or propofol infusion (group P) in order to maintain stable haemodynamics. Data of postoperative function and side‐effects were collected in a double‐blind design, including a patient interview after 24 h.Results: The sevoflurane patients had a significantly faster emergence from anaesthesia, with response to commands at 6.9±0.4 min versus 8.2±0.4 min in the propofol group (P < 0.05, mean±SD). At 15 min after surgery, group S had a better score in the digit symbol substitution test and felt less confused in a visual analogue scale test compared with group P (P<0.05). Peroperative bradycardia, nausea and vomiting and late postoperative dizziness were more common in group S. In the sevoflurane group, 32% had nausea or vomiting in the 24 h observation period compared with 18% for propofol (P < 0.05). There was no difference between group S and group P in postoperative pain, eligibility for recovery room discharge (75±12 versus 70±11 min) or home‐readiness (155±12 versus 143±11 min).Conclusion: Maintenance of anaesthesia with sevoflurane results in a more rapid emergence, but a higher incidence of nausea and vomiting compared with propofol. The side‐effects were minor in our study, and did not result in any difference in time to discharge from the recovery ward or the hospital.
Impact of autotransfusion after coronary artery bypass grafting on oxygen transport
Authors: SCHMIDT H. , FØSGAARD S. , MORTENSEN P. E. , JENSEN E. 
Published: January 2009

Background: Autotransfusion of shed mediastinal blood after coronary artery bypass grafting (CABG) has been shown to reduce the requirement for allogeneic blood. We have previously demonstrated in non‐randomized studies that the oxygen capacity of shed mediastinal blood is similar to the patient's circulating blood and better than stored allogeneic blood. Therefore, we wanted to examine the influence of autotransfusion of shed mediastinal blood on oxygen transport capacity in patients undergoing CABG.Methods: A prospective, randomized, controlled study involving 120 patients having elective, uncomplicated CABG was performed. The autotransfusion group received transfusion of shed mediastinal blood for 18 h. Both groups received allogeneic red cells if their hemoglobin concentration decreased below 5 mmol/L. Red blood cell 2, 3‐diphosphoglycerate (2, 3‐DPG) was measured preoperatively and at intervals up to the hospital discharged. Hemodynamic measurements as well as blood gas and hemoglobin measurements from samples of arterial and mixed venous blood were used for calculation of oxygen transport capacity.Results: During the autotransfusion period only 2 patients (4%) in the autotransfusion group required allogeneic blood compared to 11 patients (20%) in the control group. The 2, 3‐DPG levels in the autotransfusion group were unchanged before and after autotransfusion (4.4 vs. 4.3 umol/ml erythrocyte). In the control group, 2, 3‐DPG levels decreased from 4.3 to 3.9 umol/ ml erythrocyte during the same period. There were no differences in the other measured parameters for oxygen transport capacity between the groups.Conclusion: Autotransfusion of shed mediastinal blood conserves the 2, 3‐DPG level of the red blood cells, while transfusion of stored blood leads to a decrease in 2, 3‐DPG levels. Autotransfusion had no effect on hemodynamic parameters, oxygen delivery or oxygen extraction.