bluuebunny/crossref_metadata_2025 huggingface dataset:
Errors in the intensive care unit (ICU)
Authors: Flaatten H. , Hevrøy O.
Published: March 2003

Background: In order to obtain information about the occurrence and severity of errors in an ICU, this investigation was conducted in a combined ICU and postoperative ward at a Norwegian University Hospital.

Methods: An anonymous registration was conducted in order to reveal as many as possible of all errors in the unit. A separate registration form was used, recording the type of error, date and time, sex and age of the patient, patient condition (unstable/stable) and where the error occurred (on the ward or during transport). The registration started in October 1995, and reports until November 1996 are included (13 months). Consequences of the errors were graded using a 6‐point scale (0=no consequences and 5=fatal). Two experienced intensivists and two experienced ICU nurses independently evaluated the errors using a visual analogue scale (VAS) with 10 as the worst imaginable error. All four were blinded to consequences of the error.

Results: A total of 87 errors was reported: 36 (41.3%) were medication errors, 17 (19.5%) related to intravenous infusions, 15 (17.2%) were due to technical equipment failure, and the rest (19 errors, 21.8%) miscellaneous. No consequences could be detected in 55 cases (63%) (grade 0). Six errors were graded as 1, and 22 (25%) as grade 2 (therapeutic intervention necessary, no damage recorded). Five errors had more serious consequences, and one was fatal. The scoring of errors varied a great deal. Mean VAS score was 4.2 (SD 1.7). The sum of VAS score (max. 40) on each error followed a normal distribution, and 12 errors had a score >25.

Conclusion: Errors happen frequently in the ICU. Probably, our data do not represent the true incidence of errors in the period, which we believe was higher. Many errors are graded as serious or severe, but still have limited consequences for the patient.
Prophylactic ondansetron for postoperative emesis.Meta‐analysis of its effectiveness in patients with previous history of postoperative nausea and vomiting
Authors: Figueredo E. , Canosa L.
Published: March 2003

Background: The objective of this study was to compare, by means of meta‐analysis, the postoperative antiemetic efficacy of ondansetron in patients with and without antecedents of postoperative nausea and vomiting.

Methods: MEDLINE and EMBASE databases were searched for randomised placebo‐controlled trials which evaluated the antiemetic effectiveness of 4 mg and 8 mg intravenous doses of prophylactic ondansetron in adult patients. A further selection was with respect to those studies which noted the patient's previous history of postoperative nausea and vomiting (PH‐PONV) and, for the meta‐analysis, the patients were divided into two sub‐groups: those with (PH‐PONV +) and those without a previous history of postoperative nausea and vomiting (PH‐PONV −). Absence of vomiting was used as the index of effectiveness.

Results: Twenty‐one trials involving 3984 patients (2446 in ondansetron groups and 1538 in placebo groups; 1163 PH‐PONV(+) patients and 2821 PH‐PONV(−) patients) met the selection criteria. The effectiveness of the 4 mg dose of ondansetron was: OR (95% CI)=2.40 (1.77–3.26) vs. 2.71 (2.23–3.30) for the patients of PH‐PONV(+) and PH‐PONV(−) sub‐groups, respectively. For the 8 mg dose, the effectiveness of ondansetron was: PH‐PONV(+)=4.21 (2.66–6.66) and PH‐PONV(−)=2.61 (1.81–3.59). For neither of the doses evaluated was there any significant statistical difference between the sub‐groups.

Conclusions: The effectiveness of ondansetron in the prevention of postoperative vomiting is not affected by the patients’ PH‐PONV.
Pharmacology of G‐1–64, a new nondepolarizing neuromuscular blocking agent with rapid onset and short duration of action
Authors: Gyermek L. , Lee C. , Nguyen N.
Published: March 2003

Background: Chances are slim that a clinically useful ultra‐short‐acting neuromuscular blocking agent of rapid onset will emerge from the benzylisoquinolinium or the aminosteroid series to which all currently popular relaxants belong. G‐1–64 is a promising prototype of a new series of bis‐quaternary ammonium salt of bistropinyl diester derivatives we have synthesized and studied in the laboratory.

Methods: Neuromuscular block (NMB) and autonomic and cardiovascular side effects were studied on appropriate preparations of anesthetized rats, rabbits, cats, ferrets, pigs and monkeys. Neuromuscular blocking characteristics, cumulativeness, and pharmacological reversibility were determined. Cardiac vagal block was evaluated by the inhibition of the bradycardic response to stimulation of the vagus in the cat, rat, ferret, and pig. Sympathetic ganglion block was evaluated on the cat's superior cervical ganglion/nictitating membrane preparation. Arterial blood pressure and heart rate were determined in all species.

Results: G‐1–64 produced nondepolarizing NMB with train‐of‐four (TOF) and tetanic fades, and reversible with anticholinesterases. Its ED50 ranged between 60 and 800 μg/kg in these species. It showed a significantly faster onset (0.9–2.1 min) and/or shorter duration of action (5–12 min) than either atracurium or mivacurium. It did not show cumulativeness on repeated doses or infusion. A varying degree of cardiac vagal block was present, dependent on the species at doses exceeding the ED80 for NMB. Cardiovascular changes, ganglion block or signs suggesting histamine release were absent.

Conclusion: With favorable neuromuscular blocking characteristics and modest side effects, G‐1–64 and similar derivatives may have clinical potential.
Investigation of fading responses induced by non‐depolarising muscle relaxants in the evoked EMG of the gastrocnemius muscle of the cat
Authors: Suzuki T. , Nagai H. , Katsumata N. , Ogawa S. , Suzuki H.
Published: March 2003

Background: During partial neuromuscular blockade indirect repetitive nerve stimulation causes fade in the response of the muscle. We studied the intensity of the fade induced by intravenous administration of three steroidal muscle relaxants, and investigated the mechanism of fade by comparing with results obtained during partial blockade with animal toxins and vesamicol.

Methods: In 60 cats, we measured the fade in the compound action potentials of the gastrocnemius muscle evoked by repetitive sciatic nerve stimulation at 100 Hz during partial neuromuscular blockade with rocuronium, vecuronium, pancuronium, α‐bungarotoxin, μ‐conotoxin and vesamicol, respectively.

Results: Profound fade was induced by all three non‐depolarising muscle relaxants (rocuronium=vecuronium<pancuronium) and by vesamicol, in contrast to α‐bungarotoxin and μ‐conotoxin which induced no fading.

Conclusion: Our results suggest that non‐depolarising muscle relaxant‐induced fade is caused by an inhibitory effect on acetylcholine release. Pancuronium seems to have a higher potency of presynaptic inhibition of acetylcholine release than both rocuronium and vecuronium.
Anaesthetic management of patients with mucopolysaccharidosis IV presenting for major orthopaedic surgery
Authors: Bartz H.‐J. , Wiesner L. , Wappler F.
Published: March 2003

Mucopolysaccharidosis IV, also known as Morquio‐Brailsford syndrome, is an inherited autosomal recessive disorder of mucopolysaccharide metabolism leading to accumulation of keratan sulphate in the connective tissue of multiple organ systems. Based on a case report, the anaesthetic implications for the treatment of patients with MPS IV presenting for major orthopaedic surgery are discussed.
Postoperative respiratory arrhythmias: incidence and measurement
Authors: Sleigh J. W.
Published: March 2003

Background: Postoperative respiratory disturbances may be the result either of depression of respiratory drive, or alteration of respiratory pattern.

Methods: Using an inductance plethysmograph, we continuously recorded the breathing in 52 patients for 4 h after major thoracic, abdominal, and body surface surgery. The ventilatory response to hypercapnia was measured preoperatively, and at the start and end of the observation period.

Results: From a variety of statistical measures of respiratory depression, it was found that the occurrence of apnoeas (breath times >10 s), did not correlate with measures of respiratory drive, or with dose or route of administration of opioid, site of surgery, pain, or drowsiness. Instead, the incidence of apnoeas correlated most closely with measures of respiratory pattern (standard deviation of breath times (r=0.72), the mean breath time (r=0.63), approximate entropy of the breath times (r=−0.32)). Twenty‐nine percent of patients had some breath times (Ttot) longer than 20 s.

Conclusion: We would conclude that changes in respiratory pattern are not closely correlated with changes in traditional measures of respiratory drive.
Effects of dopamine in lung‐transplanted pigs at 32°C
Authors: Roscher R. , Ingemansson R. , Algotsson L. , Sjöberg T. , Steen S.
Published: March 2003

Background: We have used hypothermia successfully in patients with acute respiratory failure after lung transplantation. However, we have observed that dopamine may cause a substantial decrease in mean arterial pressure (MAP) in hypothermic subjects. Furthermore, a dopamine‐induced increase in pulmonary vascular resistance (PVR) has been reported in the literature, and this could aggravate the increase in PVR which is often seen both in the early postoperative phase after lung transplantation, and during hypothermia. We thus hypothesized that dopamine would decrease MAP and increase PVR in hypothermic lung‐transplanted subjects.

Methods: Left single lung transplantation combined with right pneumonectomy was performed in 6 pigs anesthetized with ketamine and midazolam and muscle relaxed with pancuronium. After an observation period of 24 h, the effect of dopamine infused at 5 and 12 μg · kg−1 · min−1 was studied in normothermia (38°C) and after cooling by cold‐water immersion to 32°C.

Results: Systemic vascular resistance index (SVRI) increased and cardiac index (CI) decreased in hypothermia. Dopamine decreased SVRI and increased CI, both in normothermia and at 32°C. MAP decreased during infusion of dopamine in hypothermia. Dopamine had no effect on the pulmonary vascular resistance index (PVRI).

Conclusion: The results suggest that dopamine may be used to increase cardiac output after lung transplantation in moderate hypothermia as well as in normothermia, but one should be aware that dopamine may cause a substantial decrease in blood pressure, depending on the prevailing hemodynamic conditions at the start of its administration.
Factors affecting gentamicin pharmacokinetics in septic patients
Authors: Tang G. J. , Tang J. J. , Lin B. S. , Kong C. W. , Lee T. Y.
Published: March 2003

Background: This prospective, comparative study was designed to estimate the volume of distribution (Vd) and elimination rate constant (Ke) of gentamicin and to determine the clinical factors affecting the pharmacokinetics of gentamicin in different stages of sepsis.

Method: Seventy‐seven critically ill patients treated with gentamicin for gram‐negative sepsis were included. These septic patients were divided into hyperdynamic septic and hypodynamic septic groups according to cardiac index. Twenty‐seven patients who received postoperative prophylactic gentamicin were recruited as controls.

Results: Fifty‐two patients in the hyperdynamic septic group had a significantly larger Vd than those in the hypodynamic septic and control groups. The Vd was correlated significantly with both Acute Physiological Score (APS) (r=0.340, P<0.01) and cardiac index (r=0.394, P<0.01). The Ke of gentamicin correlated significantly with both blood urea nitrogen (BUN) (r=0.565, P<0.01) and serum creatinine level (r=0.563, P<0.01).

Conclusion: The increased Vd in the septic patients was related to the severity of illness and magnitude of cardiac output. The Ke of gentamicin was correlated with the serum creatinine level.
Does desflurane alter left ventricular function when used to control surgical stimulation during aortic surgery?
Authors: Eyraud D. , Benmalek F. , Teugels K. , Bertrand M. , Mouren S. , Coriat P.
Published: March 2003

Background: Although desflurane is commonly used to control surgically induced hypertension, its effects on left ventricular (LV) function have not been investigated in this clinical situation. The purpose of the present study was to evaluate the LV function response to desflurane, when used to control intraoperative hypertension.

Methods: In 50 patients, scheduled for vascular surgery, anesthesia was induced with sufentanil 0.5 μg/kg, midazolam 0.3 mg/kg and atracurium 0.5 mg/kg. After tracheal intubation, anesthesia was maintained with increments of drugs with controlled ventilation (N2O/O2=60/40%) until the start of surgery. A 5 Mhz transesophageal echocardiography (TEE) probe was inserted after intubation. Pulmonary artery catheter and TEE measurements were obtained after induction (t0)(control value), at surgical incision (t1) if it was associated with an increase in systolic arterial pressure (SAP) greater than 140 mmHg (hypertension) and after control of hemodynamic parameters by administration of desflurane (return of systolic arterial pressure to within 20% of the control value) (t2) in a fresh gas flow of 3 l/min.

Results: Sixteen patients developed hypertension at surgical incision. SAP was controlled by desflurane in all 16 patients. Afterload assessed by systemic vascular resistance index (SVRI), end‐systolic wall‐stress (ESWS) and left‐ventricular stroke work index (LVSWI) increased with incision until the hypertension returned to post‐induction values with mean end‐tidal concentration of 5.1±0.7% desflurane. No change in heart rate, cardiac index, mean pulmonary arterial pressure, stroke volume, end‐diastolic and end‐systolic cross‐sectional areas, fractional area change and left ventricular circumferential fiber shortening was noted when desflurane was added to restore blood pressure.

Conclusion: This study demonstrates that in patients at risk for cardiac morbidity undergoing vascular surgery, desflurane is effective to control intraoperative hypertension without fear of major cardiac depressant effect.
Halothane decreases bacterial adherence in vitro
Authors: Batai I. , Kerenyi M.
Published: March 2003

Background: Adherence of pathogenic bacteria to host epithelial cells is thought to be the initial step in infection, while the presence of the commensal flora is an important host defence mechanism. Anything altering bacterial adherence to human epithelial cells may contribute to bacterial infections. The impact of anaesthesia on this first step to infection is not known. In this study the effect of halothane on bacterial adherence was investigated.

Methods: Human epithelial cells (HEp‐2) and two strains of Escherichia coli were exposed to halothane 2% for 2 h. Then HEp‐2 cells were coincubated with bacteria for 3 h. Bacteria attached to the epithelial cells were evaluated by light microscopy.

Results: Compared to the control, bacterial adherence was reduced by 37% to 56% with the different strains when HEp‐2 cells were exposed to halothane. No significant difference was found when only bacteria were treated with halothane.

Conclusion: Our results show that halothane reduces bacterial adherence to human epithelial cells in vitro. Reduced number or function of epithelial cell surface receptors may be responsible for the reduced adherence as no changes were observed when only the bacteria were exposed to halothane.
Caffeine‐ or halothane‐induced contractures of masseter muscle are similar to those of vastus muscle in normal humans
Authors: Melton A. T. , Antognini J. F. , Gronert G. A.
Published: March 2003

Background: Skinned fibers from normal human masseter muscle have greater caffeine and calcium sensitivity than skinned fibers from vastus muscle. We examined sensitivity to caffeine and halothane in fresh, cut muscle bundles (non‐skinned) from human masseter muscle.

Methods: Masseter bundles (caffeine, n=25, halothane, n=19) excised from 10 humans under general anesthesia had tension measured in 37°C baths during the addition of caffeine (0.5, 1, 2, 4, 8, 32 mM) or 3% halothane. Results were compared to those of our previous studies (1989, 1997, 25 patients) of vastus bundles (caffeine, n=71, halothane, n=63) using the same protocol, technicians, and equipment.

Results: Baseline force in the caffeine test was 2.10±1.57 for masseter, and 2.02±1.68 and 1.82±1.29 respectively for vastus muscle. Force at 32 mM caffeine concentration was 11.2±9.9 g for masseter, 11.0±5.4 and 13.5±7.5 g for vastus. Concentration‐response curves were virtually identical. In the halothane group, neither baseline values (masseter 1.47±1.30, vastus 1.91±1.32 and 2.15±1.71) nor contractures in response to 3% halothane were different. Most bundles had no contracture in response to 3% halothane; 3 masseter bundles and 2 vastus bundles (1989) developed contractures of less than 0.05 g. Three vastus bundles (1997) developed contractures >0.2 g.

Conclusion: Contracture responses of intact cut masseter and vastus bundles (non‐skinned) do not differ with respect to caffeine and halothane. Responses of skinned fibers might demonstrate greater sensitivity under certain conditions, but they do not reflect those of intact cut bundles.
Surveillance of antibiotic resistance in ICUs in southeastern Sweden
Authors: Erlandsson C.‐M. , Hanberger H. , Eliasson I. , Hoffmann M. , Isaksson B. , Lindgren S. , Nilsson L. E. , Sörén L. , Walther S. M. ,   the ICU Study Group of the South East of Sweden
Published: March 2003

Background: A study was designed to assess a computer‐based program for continuous registration of antibiotic resistance, statistics concerning severity of illness, and consumption of antibacterial drugs.

Methods: The frequency of antibiotic resistance among bacteria in eight ICUs in southeastern Sweden was investigated yearly from 1995 through 1997. The antibiotic consumption in the ICUs was registered as defined daily doses (DDD) and compared to severity of illness (APACHE‐II scores).

Results: There was a statistically significant increase in ampicillin resistance among Enterococcus spp. between 1996 and 1997, which was due to a shift from Enterococcus faecalis to Enterococcus faecium. A high prevalence of resistance among coagulase‐negative staphylococci to oxacillin (≈ 70%), ciprofloxacin (≈ 50%), fucidic acid (≈ 50%) and netilmicin (≈ 30%) was seen in all ICUs during the whole study period. There was a statistically significant increase in ciprofloxacin resistance among Escherichia coli and Enterococcus spp. The resistance among Enterobacter spp. to cefotaxime decreased but this change was not statistically significant. Efforts were made to avoid betalactam antibiotics, except carbapenems, for treatment of infections caused by Enterobacter spp. and the consumption of cephalosporins decreased whereas the consumption of carbapenems increased. The total antibiotic consumption decreased by 2.5% during the study period. There was no correlation between APACHE II scores and antibiotic consumption.

Conclusions: Each ICU within a hospital ought to have a program for “on‐line” antibiotic resistance surveillance of drugs used in that unit so that changes in empirical treatment can be made when there is an increase in antibiotic‐resistant isolates within that unit.
Permissive hypercapnia during thoracic anaesthesia
Authors: Morisaki H. , Serita R. , Innami Y. , Kotake Y. , Takeda J.
Published: March 2003

Background: While permissive hypercapnia is commonly practised in critical care, it remains unclear if the comparable manoeuvres are clinically acceptable during anaesthesia. This retrospective study aimed at describing the anaesthetic implications of hypercapnia associated with deliberate hypoventilation during thoracic surgery in patients with severe emphysema.

Methods: Thirteen patients with emphysema who required thoracic surgery under similar anaesthesia were reviewed: 3 patients were managed to maintain normocapnia (normocapnia group) whereas 10 patients developed hypercapnia (PaCO2 >70 mmHg) as a result of restricting peak airway pressures (hypercapnia group).

Results: In the normocapnia group (PaCO2: 45±1 mmHg, mean±SD), no event which required therapeutic intervention during the surgery was seen, whereas 2 of 3 patients showed postoperative air leakage which persisted over 5 days. In the hypercapnia group, the maximum PaCO2 during anaesthesia ranged between 70 mmHg and 135 mmHg (98±21 mmHg). During anaesthesia, all 10 patients required inotropic support to prevent hypotension, 4 patients required tracheal gas insufflation of oxygen to the operated lung to avoid hypoxaemia and 3 patients required lidocaine to treat ventricular arrhythmia. However, the trachea was extubated in the operation theatre in 9 of 10 patients and no organ dysfunction was observed postoperatively. Four patients showed postoperative air leak on the first postoperative day, one of which persisted over 5 days.

Conclusion: Although there are some limitations, this preliminary study indicates that hypercapnia around 100 mmHg during anaesthesia for thoracic surgery may not be associated with serious consequences.
Plasma paracetamol concentrations and pharmacokinetics following rectal administration in neonates and young infants
Authors: Hansen T. G. , O’Brien K. , Morton N. S. , Rasmussen S. N.
Published: March 2003

Background: Despite widespread use in children pharmacokinetic data about paracetamol are relatively scarce, not the least in the youngest age groups. This study aimed to describe plasma paracetamol concentrations and pharmacokinetics of a single rectal paracetamol dose in neonates and young infants.

Methods: Perioperatively, 17 neonates and infants ≤160 days of age received one rectal paracetamol dose (mean 23.9 mg/kg (±4.2 mg/kg)). Blood samples were drawn at 60, 120, 180, 240, 300 and 360 min, according to the infants’ weights. Plasma paracetamol concentrations were measured by a Colorometric Assay, Ectachem Clinical Chemistry Slides (Johnson & Johnson Clinical Diagsnostics).

Results: The plasma paracetamol concentrations were mainly below the therapeutic (i.e. antipyretic) range of 66–132 μmol/l and did not exceed 160 μmol/l in any infant. The mean maximum plasma concentration (Cmax) was 72.4 μmol/l (±33.5 μmol/l) and the time to Cmax, i.e. the mean Tmax was 102.4 min (±59.1 min). The mean “apparent” terminal half‐life (n=10) was 243.6 min (±114.1 min).

Conclusion: The absorption of rectal paracetamol (mean dose 23.9 mg/kg, ±4.2mg/kg) in young infants <160 days is variable and often prolonged and achieves mainly subtherapeutic plasma concentrations.
Vasopressin and angiotensin II in blood pressure control during isoflurane anesthesia in rats
Authors: Ullman J.
Published: March 2003

Background: Hormonal systems such as vasopressin (AVP) and the renin‐angiotensin‐aldosterone system (RAS) have been reported to become activated during anesthesia and surgery. The purpose of this study was to examine the relative importance of AVP and angiotensin II (AII) in blood pressure control during isoflurane anesthesia in rats.

Methods: Rats were given an AVP V1‐receptor antagonist (AVP‐a, 10 μg kg−1), the AII receptor antagonist saralasin (SAR, 20 μg kg−1 min−1) and hexamethonium (HEX, 10 mg kg−1) intravenously in random order, awake or anesthetized with isoflurane.

Results: AVP‐a had no effect on mean arterial pressure (MAP) in awake or anesthetized animals, but reduced MAP by 20.0±2.2% in the anesthetized rats which previously had been treated with SAR and/or HEX. SAR infusion had no effect on MAP when administered to conscious rats, but decreased MAP by 12.0±4.4% during anesthesia. Ganglionic blockade with HEX consistently lowered MAP in the conscious and anesthetized animals.

Conclusion: It is concluded that AVP contributes to the maintenance of blood pressure when the autonomic nervous system (ANS) and/or RAS are blocked during isoflurane anesthesia. SAR infusion leads to hypotension during anesthesia, but not in conscious rats. These findings indicate that AII is of importance for blood pressure maintenance during isoflurane anesthesia in rats, and that apparent pressor effects of AVP come into play when RAS and/or ANS are blocked.
Possible venous argon gas embolism complicating argon gas enhanced coagulation during liver surgery
Authors: Stojeba N. , Mahoudeau G. , Segura P. , Meyer C. , Steib A.
Published: March 2003

We report a case of a major venous argon embolism during argon beam coagulation of a liver biopsy. The essential signs were an abrupt reduction in end‐tidal carbon dioxide partial pressure, in SpO2 and in systolic arterial pressure, at the time of coagulation. Spontaneous recovery was observed within 10 min. Precautions in respect of usage are highlighted.
Does use of propofol in heavy alcohol drinkers tend to discolor their urine?
Authors: Kato N. , Ogawa R.
Published: March 2003

A case in which the urine of a patient who was a heavy drinker turned pink when propofol was used for anesthesia is reported, and a new cause of the urine discoloration is proposed.
Convulsions and respiratory arrest in association with desmopressin administration for the treatment of a bleeding tonsil in a child with borderline haemophilia
Authors: Francis J. D. , Leary T. , Niblett D. J.
Published: March 2003

Desmopressin (DDAVP) may be used to augment the action of factor VIII in mild haemophilia. Its use has been associated with serious adverse effects. We report a case of a three‐year‐old child with a family history of haemophilia who suffered complications due to severe acute hyponatraemia following the administration of this drug for post‐tonsillectomy bleeding.
The effects of two rewarming strategies on heat balance and metabolism after coronary artery bypass surgery with moderate hypothermia
Authors: Hanhela R. , Mustonen A. , Korhonen I. , Salomäki T.
Published: March 2003

Background: Postoperative hypothermia is common in cardiac surgery with hypothermic cardiopulmonary bypass (CPB). This trial was designed to evaluate whether rewarming over the normal bladder temperature (over 37°C) at the end of hypothermic CPB combined with passive heating methods after CPB might result in a better heat balance, lower energy expenditure (EE) and decrease of disturbances in oxygen balance compared to only rewarming the patients to a bladder temperature of 35–37°C.

Methods: A prospective, randomized controlled clinical study was performed in 38 patients scheduled for elective coronary artery bypass surgery. Twenty patients (group C) were rewarmed to a bladder temperature of 35–37°C at the end of hypothermic (28°C) CPB. Eighteen patients (group W) were rewarmed to a bladder temperature of 37–38.5°C.

Results: At the end of CPB, the bladder temperature was 36.2±0.7°C (mean±SD) in group C and 37.9±0.5°C in group W. After half an hour’s stay in the ICU, the mean body temperature (MBT) was 35.1±0.6°C in group C and 36.6±0.7°C in group W. During the following five hours, MBT increased to 37.4±0.8°C in group C and to 38.0±0.6°C in the other group. The peak value of EE in the ICU was 1.73±0.44 (group C) vs 1.35±0.29 (W/kg) (group W) (P=0.003). EE was significantly (P=0.044 ) higher in group C than in the other group between 1.5 and 5.5 h in the ICU. The increased energy expenditure due to heat production was associated with an increase in O2 consumption (V˙O2) 61.6±30.4% vs 25.2±24.1%, (peak values) compared to the basal values of the two groups measured before anesthesia (between groups P<0.001). Between 1.5 and 5.5 h in the ICU, group C had significantly higher V˙O2 (P=0.026), CO2 production (P=0.017), venous pCO2 (P<0.001) and minute ventilation (p=0.014) than group W. Venous pH was lower (P<0.001) in group C. The peak value of oxygen extraction was also higher (P=0.045) in group C. On the other hand, the lowest value of venous oxygen saturation was higher (P=0.04) in group W.

Conclusion: With rewarming the patients at the end of CPB to a bladder temperature of over 37°C combined with passive heating methods after CPB, it was possible to decrease EE and V˙O2 compared to the control group (rewarmed to bladder temperature of 35–37°C) after coronary artery bypass surgery with moderate hypothermia.
Stereoselective pharmacokinetics of ketorolac in children, adolescents and adults
Authors: Hamunen K. , Maunuksela E.‐L. , Sarvela J. , Bullingham R. E. S. , Olkkola K. T.
Published: March 2003

Background: Previous pharmacokinetic studies on racemic ketorolac using nonstereoselective analytical methods have indicated that the plasma clearance of ketorolac is higher and the volume of distribution greater in children than in adults. The aim of this study was to study the stereoselective pharmacokinetics of racemic ketorolac in children, adolescents and adults.

Methods: 18 children (6–11 yrs), 18 adolescents (12–17 yrs) and 18 adults (18–44 yrs) participated in the study. At the end of eye surgery they were given intravenous racemic ketorolac tromethamine 0.5 mg/kg. Plasma samples were assayed for (R)‐ and (S)‐ketorolac with high‐pressure liquid chromatography. Clearance (CL), volume of distribution at steady state (Vss) and elimination (Vz) and elimination half‐life (t1/2,z) were calculated with standard methods. Incidence of side‐effects were recorded.

Results: CL, Vss, Vz and t1/2,z were higher (P<0.05) for (S)‐ketorolac than for the (R)‐enantiomer. Vss of the active (S)‐enantiomer was higher in children than in adolescents (P<0.05) and adults (P<0.001) but the values for CL were similar. Due to the higher volume of distribution, t1/2,z was also higher in children than in adults. The pharmacokinetics of the (R)‐enantiomer were essentially unaffected by age.

Conclusion: On a pharmacokinetic basis, the maintenance dose requirements of ketorolac are similar in children, adolescents and adults.
The pressor response after laryngeal mask or cuffed oropharyngeal airway insertion
Authors: Casati A. , Cappelleri G. , Fanelli G. , Magistris L. , Beccaria P. , Albertin A. , Torri G.
Published: March 2003

Background: Since the cuffed oropharyngeal airway (COPA) has been suggested to cause less pharyngeal trauma than the laryngeal mask airway (LMA), we conducted a prospective, randomised study to compare haemodynamic changes after placing either the COPA or LMA in healthy anaesthetised adults.

Methods: After standard midazolam premedication (0.05 mg kg−1 IV), general anaesthesia (IV propofol 2 mg kg−1) was induced in 60 ASA physical status I–II, 18–65‐yr‐old patients, who were randomly allocated to receive COPA (n=30) or LMA (n=30) placement and then mechanically ventilated using a 60% nitrous oxide and 1% isoflurane in oxygen mixture (TV=8 ml kg−1, RR=12 b.p.m., I/E=1/2). Haemodynamic variables were recorded 20 min after the midazolam premedication (baseline), and then every 1 min until 10 min after general anaesthesia induction.

Results: Nine patients of group COPA (30%) required chin lift, jaw thrust or head tilt to maintain adequate ventilation, while no problems were observed in the LMA group (P<0.0005); however, in no case did the designed extratracheal airway have to be removed due to unsuccessful mechanical ventilation, and no signs of gastric insufflation or regurgitation were reported. The maximum mean changes in haemodynamic variables were more marked after LMA placement (SAP: 12%±13%; DAP: 11%±18%; HR: 13%±16%) than COPA placement (SAP: −3%±18%; DAP: −5%±16%; HR: 4%±13%) (P<0.005, P<0.005, and P<0.01 for SAP, DAP and HR, respectively). Group LMA showed higher SAP and DAP values than group COPA only during the first 3 min after airway insertion.

Conclusion: In healthy, anaesthetised patients, placing a cuffed oropharyngeal airway is associated with smaller cardiovascular changes after airway insertion compared with the laryngeal mask airway.
A survey of current usage of anticholinergic drugs in paediatric anaesthesia in Finland
Authors: Rautakorpi P. , Manner T. , Kanto J.
Published: March 2003

Background: The aim of this survey was to obtain information about the current use of anticholinergic preanaesthetic medication in children. It was carried out as a follow‐up study of the previous survey amongst Finnish anaesthesiologists in 1990.

Methods: A questionnaire was send to all members of the Finnish Society of Anaesthesiologists. Data from anaesthesiologists taking care of at least three paediatric anaesthesias/week (n=183) were analyzed.

Results: In 1998 only one‐third of the Finnish anaesthesiologists routinely used anticholinergics before paediatric anaesthesia. The main indications for routine anticholinergic premedication were ENT surgery (66%), eye surgery (71%) and endoscopic procedures (67%). Anticholinergic drugs were administered principally via the intravenous route (90%) briefly before induction of anaesthesia, and glycopyrrolate was the most frequently used (66%).

Conclusion: During the last eight years in Finland the routine use of anticholinergic premedication has decreased. As in 1990 the anticholinergic prophylaxis is directed to ENT and eye surgery, endoscopic procedures and to children younger than 1 year. Use of glycopyrrolate has gained popularity at the expense of atropine and scopolamine.
Xenon inhalation increases airway pressure in ventilated patients
Authors: Rueckoldt H. , Vangerow B. , Marx G. , Haubitz B. , Cobas Meyer M. , Piepenbrock S. , Leuwer M.
Published: March 2003

Background: The inert gas xenon, known as an anaesthetic for nearly 50 years, is also used as a contrast agent during computerised tomography (CT)‐scanning. As xenon has a higher density and viscosity than air, xenon inhalation may increase airway resistance.

Methods: In a retrospective study we investigated the effects of 33% xenon/67% oxygen on airway pressure and cardio‐respiratory parameters in 37 long‐term mechanically ventilated patients undergoing cerebral blood flow (rCBF) measurements by means of stable xenon‐enhanced CT.

Results: Xenon administration caused a significant increase in peak airway pressure from 31.6±8.0 cm H2O to 42.7±16.9 cm H2O. This effect was reproducible, did not occur after reduction of inspiratory flow rate by 50% from 0.56±0.15 L  ·  s−1 to 0.28±0.08 L  ·  s−1, and vanished immediately after termination of xenon delivery.

Conclusion: Due to the higher density and viscosity of this gas mixture, ventilation with xenon/oxygen produces a higher Reynolds’ number than oxygen/air when given at the same flow rate. This means that during xenon ventilation the zone of transition from turbulent to laminar gas flow may be located more peripherally (in smaller airways) than during oxygen/air ventilation with a subsequent increase in airway resistance. Our results indicate that xenon inhalation may cause a clinically relevant increase of peak airway pressure in mechanically ventilated patients.
Effects of vecuronium and rocuronium in antagonistic laryngeal muscles and the anterior tibial muscle in the cat
Authors: Michalek‐Sauberer A. , Gilly H. , Steinbereithner K. , Vizi E. S.
Published: March 2003

Background: Adequate vocal cord paralysis and full recovery of laryngeal muscle function are important when muscle relaxants are used perioperatively. This study was designed to compare the effects of vecuronium and rocuronium at the vocal cord abductor and adductor muscles and the anterior tibial muscle in cats.

Methods: Twelve adult cats were studied under pentobarbitone‐N2O/O2‐anesthesia. After supramaximal electrical stimulation of the peroneal nerve and the recurrent laryngeal nerve (0.1 Hz and intermittent train‐of‐four) evoked electromyographic responses were obtained from the anterior tibial muscle, the posterior cricoarytenoid muscle (vocal cord abductor) and two vocal cord adductor muscles, the lateral cricoarytenoid and the vocal muscle. Six cats received bolus doses of increasing size of vecuronium (ED90 22.5 μg  ·  kg−1) and six cats rocuronium (ED90 90 μg  ·  kg−1).

Results: Equipotent doses of vecuronium and rocuronium caused a similar degree of paralysis in all muscles (vecuronium ED90: 70% blockade at the posterior cricoarytenoid, 83% at the lateral cricoarytenoid, 84% at the vocal muscle and 90% at the anterior tibial muscle; rocuronium ED90: 71% at the posterior cricoarytenoid, 67% at the lateral cricoarytenoid, 78% at the vocal muscle and 90% at the anterior tibial muscle; vecuronium 2×ED90: 93% blockade at the posterior cricoarytenoid, 95% at the lateral cricoarytenoid, 97% at the vocal muscle and 99% at the anterior tibial muscle; rocuronium 2×ED90: 89% blockade at the posterior and lateral cricoarytenoid, 93% at the vocal muscle and 100% at the anterior tibial muscle). Onset time was significantly shorter at the posterior cricoarytenoid muscle (290 s) compared to the lateral cricoarytenoid muscle (400 s) after vecuronium ED90 and to the vocal muscle (150 s versus 210 s) after rocuronium ED90. Compared to the anterior tibial muscle (interval 25–75%: 6.5 min after vecuronium 2×ED90 and 3.3 min after rocuronium 2×ED90) and to the posterior cricoarytenoid muscle (interval 25–75%: 7 min after vecuronium 2×ED90 and 4.3 min after rocuronium 2×ED90), recovery of laryngeal adductor muscle function was markedly delayed with both neuromuscular blocking drugs (interval 25–75% at the lateral cricoarytenoid and vocal muscle: 14 min and 15.8 min after vecuronium 2×ED90 and 10.3 min and 11.6 min after rocuronium 2×ED90 respectively).

Conclusion: In cats, the time course of neuromuscular blockade after vecuronium and rocuronium differs in antagonistic laryngeal muscles. The protective laryngeal function of glottis closure recovers later than vocal cord abduction after both vecuronium and rocuronium.
Local anaesthesia for awake fibreoptic nasotracheal intubation
Authors: Kundra P. , Kutralam S. , Ravishankar M.
Published: March 2003

Background: Awake fibreoptic nasotracheal intubation (FNI) is performed in potentially difficult airways under local anaesthesia. This observer‐blinded study was designed to evaluate the efficacy of upper airway anaesthesia produced by nebulized lignocaine against combined regional block (CRB) for awake FNI.

Methods: Forty‐eight ASA 1 adults were randomly allocated to receive 4 ml of 4%‐nebulized lignocaine (nebulization group) or translaryngeal block, bilateral superior laryngeal nerve block and three 4% lignocaine‐soaked cotton swabs in the nose (CRB group). Facial grimace and patient comfort were assessed by grimace and airway reactivity scores. Patients reported their discomfort on a 4‐point score.

Results: All patients underwent successful FNI without significant discomfort; 79% in the nebulization group and 83% of the patients in the CRB group reported the procedure to be comfortable. A higher grimace score was recorded on insertion of the endotracheal tube (ETT) through the nostril in the nebulization group when compared to the CRB group, P<0.005. Similarly, patients in the CRB group were more comfortable during passage of the ETT into the glottis, as compared to the nebulization group. A progressive increase in heart rate was observed in all patients from the beginning of the procedure, but the rise in the nebulization group was greater, (P<0.05) and also lasted longer than in the CRB group (P<0.05). Mean arterial pressure was higher in the nebulization group when compared to the CRB group (P<0.05), with patients belonging to the CRB group demonstrating considerable haemodynamic stability.

Conclusions: Both nebulization and CRB produced satisfactory anaesthesia of the upper airway, but CRB provided better patient comfort and haemodynamic stability.
Injection of morphine loco dolenti recommended as early as 1876
Authors: Tammisto T. , Tammisto CH.
Published: March 2003

The peripheral site of action of opioids was proved some 20 years ago. The concept of the peripheral action of morphine, however, appears to be over 100 years older.

We report on the contents of a paper, presented on 28 April 1876 at the meeting of the Finnish Medical Association (“Finska Läkarsällskapet”), on the use of morphine and its sites of action. The author was Professor Knut Felix von Willebrand, whose details are included.

Prof. v. Willebrand starts by focusing on several unwanted side effects, often seen in connection with morphine administration, and advises how they can be avoided by using the pupils of the eye as a manometer for tolerance of morphine, as suggested by Vibert. After having presented four case reports which illustrate the use of morphine in his own practice, Prof. v. Willebrand explains his conception of the sites of action of morphine.

The paper gives a lively picture of the use of morphine about 125 years ago. Furthermore, it indicates that Prof. v. Willebrand believed firmly in the peripheral site of action of morphine and recommended to inject morphine loco dolenti whenever possible.
Regional anaesthesia for outpatient knee arthroscopy: a randomized clinical comparison of two different anaesthetic techniques
Authors: Casati A. , Cappelleri G. , Fanelli G. , Borghi B. , Anelati D. , Berti M. , Torri G.
Published: March 2003

Background: The purpose of this prospective, randomized study was to evaluate the time required to perform anaesthesia, achieve surgical block and fulfil standardized discharge criteria in outpatients receiving knee arthroscopy with either spinal anaesthesia or combined sciatic‐femoral nerve block.

Methods: After a standard midazolam/ketoprofen premedication and baseline measurement of cardiovascular parameters, 50 ASA I–II patients scheduled for elective outpatient knee arthroscopy were randomized to receive spinal anaesthesia with 8 mg of 0.5% hyperbaric bupivacaine (group Spinal, n=25), or combined sciatic‐femoral nerve block with 25 ml of mepivacaine 20 mg ml−1 and a multiple injection technique (15 ml for femoral nerve block and 10 ml for sciatic nerve block). Times lasting from skin disinfection to the end of local anaesthetic injection (preparation time) and then to achieve surgical anaesthesia (readiness for surgery), as well as times required for block resolution, micturition, unassisted ambulation, and home discharge were recorded by a blinded observer. Occurrence of adverse events was also recorded.

Results: Preparation time (mean±SD) was longer with sciatic‐femoral block (8±2.7 min) than spinal anaesthesia (5±2.1 min) (P=0.0002) while no differences were observed in the time required to achieve readiness for surgery (14±5 min and 15±6 min in the Spinal and Sciatic‐femoral groups, respectively). No differences in haemodynamic side effects and need for intraoperative additional analgesia were observed. Patients receiving spinal anaesthesia showed a faster resolution of nerve block and longer time to micturition (137±49 min and 231±101 min) than patients receiving peripheral nerve blockade (206±51 min and 145±36 min) (P<0.0005 and P=0.002, respectively); however, no differences were observed in the time required to fulfil standardized discharge criteria (241±101 min in group Spinal and 209±70 min in group Sciatic‐femoral; P=0.86).

Conclusion: In patients receiving elective outpatient knee arthroscopy, using a combined sciatic‐femoral nerve block with 25 ml of mepivacaine 20 mg ml−1 and a multiple injection technique results in a slightly longer preoperative time but provides similarly effective anaesthesia with no differences in home discharge times as compared to spinal anaesthesia with 8 mg hyperbaric bupivacaine.
The effect of paracetamol (acetaminophen) on fentanyl metabolism in vitro
Authors: Feierman D. E.
Published: March 2003

Background: Fentanyl is a synthetic opioid widely used in anesthesia and analgesia. In experimental animals and in humans it has been shown that most fentanyl biotransformation occurs in the liver, where this opioid is converted primarily to its N‐dealkylated derivative, norfentanyl. Recent studies have shown that fentanyl is metabolized to norfentanyl via cytochrome P‐450 3A4 (CYP3A4). CYP3A4 is responsible for the metabolism of numerous other therapeutic agents, including those administered concurrently with fentanyl (e.g., nifedipine, lidocaine, erythromycin and cyclosporine). Paracetamol is also metabolized by the CYP3A family, with a Km that is nearly equal to therapeutic blood concentrations. Since paracetamol is widely used, its potential interaction with fentanyl metabolism would be of great interest.

Methods: In the present study, rat and human liver microsomes were used to assess the ability of paracetamol to inhibit fentanyl metabolism.

Results: In both sets of microsomes, paracetamol produced a concentration‐dependent inhibition of fentanyl oxidation to norfentanyl. Kinetic analysis of the data showed that 0.5–5 mM paracetamol inhibited fentanyl metabolism in a noncompetitive fashion. A Dixon plot revealed that the Ki for paracetamol inhibition of fentanyl metabolism is approximately 3.2 mM and 2.8 mM for human and rat liver microsomes, respectively.

Conclusions: Since these concentrations of paracetamol are approximately one order of magnitude greater than therapeutic concentrations, it would appear that potentially important and possibly harmful fentanyl–paracetamol drug interactions do not occur with therapeutic concentrations of paracetamol.
Accurate monitoring of blood loss: thoracic electrical impedance during hemorrhage in the pig
Authors: Krantz T. , Cai Y. , Lauritsen T. , Warberg J. , Secher N. H.
Published: March 2003

Background: Cardiovascular variables are closely regulated in that they remain relatively stable during minor hemorrhage. We considered that such stability would make these variables less accurate for monitoring a blood loss. In contrast, thoracic electrical impedance would be unlikely to be a regulated variable and could serve as a non‐invasive monitor of a volume deficit.

Methods: In 10 pigs bled (0–24 ml kg−1) and retransfused (to 28 ml kg−1) during halothane anesthesia, the magnitude of the electrical impedance, cardiovascular, blood gas and temperature variables, atrial natriuretic peptide and near infrared spectroscopy of the leg muscles were recorded.

Results: During hemorrhage and retransfusion, the median correlations between changes in the magnitude of the thoracic impedance and the external blood loss ranged from 0.97 to 0.98 with an individual range from 0.80 to 1.0. These correlation coefficients were higher and their ranges were lower than correlations established for any other measured parameter.

Conclusion: During hemorrhage and retransfusion in the halothane anesthetized pig, a change in the magnitude of thoracic electrical impedance appears to be an accurate and also non‐invasive monitor of a blood volume deficit.
Effect of intra‐aortic magnesium on renal function during and after abdominal aortic surgery: A pilot study
Authors: Bäcklund M. , Pere P. , Lepäntalo M. , Lehtola A. , Lindgren L.
Published: March 2003

Background: Infrarenal aortic cross‐clamping causes renal vasoconstriction. Magnesium may protect against renal deterioration through its vasodilatory properties.

Methods: Thirty patients with normal preoperative renal function undergoing infrarenal aortic cross‐clamping for elective aortic surgery received magnesium (4 mmol) or saline into the aorta immediately after aortic cross‐clamping and again just before unclamping in a double‐blind fashion. Pulmonary artery occlusion pressure was maintained ≥15 mmHg. Five patients with magnesium were excluded due to need for intravenous nitroglycerine because of myocardial ischaemia during the study.

Results: Postoperative creatinine clearance remained unchanged in both groups. Urinary N‐acetyl‐β‐D‐glucosaminidase excretion increased before and decreased after aortic cross‐clamping in both groups. The concentrations of glutathione peroxidase in serum were identical between the two groups.

Conclusions: These data indicate that intra‐aortic magnesium had no effect on renal function during or after aortic cross‐clamping.