Showing papers in "Acta Anaesthesiologica Scandinavica in 1991"

Intravenous morphine and oxycodone for pain after abdominal surgery.

Abstract: Intravenous morphine and oxycodone were given double blind in doses of 0.05 mg/kg after major abdominal surgery to 39 patients. The dosing interval was 5 min, until the patient did not want any further analgesics. Less oxycodone was needed than morphine, both to achieve the "first state of pain relief" (13.2 mg vs. 24.9 mg) and during the whole 2-h study period (21.8 mg vs. 34.2 mg). The "first state of pain relief" was achieved faster (28 min vs. 46 min) and lasted longer (39 min vs. 27 min) with oxycodone than morphine. Morphine caused more sedation and a greater decrease in the mean arterial blood pressure than oxycodone. In other respects the two opioids were comparable.

A comparison of median frequency, spectral edge frequency, a frequency band power ratio, total power, and dominance shift in the determination of depth of anesthesia.

Abstract: Five numerical descriptors were derived from the electroencephalogram (EEG), recorded, and processed (Tracor Nomad) during emergence from isoflurane-nitrous oxide anesthesia The five descriptors (median frequency, spectral edge frequency-90%, total power, a frequency band power ratio, and the ratio of frontal to occipital power) were compared for their ability to predict imminent arousal Arousal was defined as spontaneous movement, coughing or eye opening All of the descriptors except the frontal-occipital power ratio underwent significant (P less than 005) changes between the initial recordings made intraoperatively during surgical stimulus under anesthesia and later recordings in the 40 s preceding arousal A post hoc analysis was performed to identify the threshold value for each parameter that best served to predict imminent arousal For median frequency, spectral edge frequency-90%, total power, and the frequency band power ratio, thresholds that predicted imminent arousal with sensitivities of 90% and specificities of 82-90% could be identified The data indicate that, even in the favorable circumstances of the present study (uniform anesthetic technique, post hoC identification of thresholds), none of several previously popularized EEG descriptors (median frequency, spectral edge frequency-90%, total power, a frequency band power ratio) can serve as a completely reliable sole predictor of imminent arousal As presently derived, these EEG descriptors at best provide trend information to be used in concert with other clinical signs of depth of anesthesia

Long-term intrathecal morphine and bupivacaine in "refractory" cancer pain. I. Results from the first series of 52 patients.

Abstract: Neither epidural (EDA) or intrathecal (IT) morphine nor EDA opiate + bupivacaine provides acceptable relief of some types of cancer pain, e.g. pain originating from mucocutaneous ulcers, deafferentation pain, continuous and intermittent visceral and ischaemic pain, and that occurring with body movement as a result of a fracture. To improve pain relief in such conditions, we gave combinations of morphine and bupivacaine through open IT-catheters to 52 patients with "refractory", severe (VAS 7-10 out of 10), complex cancer pain (Edmonton Stage-3), for periods of 1-305 (median = 23) days. The efficacy of the treatment was estimated from: 1) daily dosage (intraspinal and total opiates, and intraspinal bupivacaine), and 2) scores of non-opiate analgesic and sedative consumption, gait and daily activities, and amount and pattern of sleep. Forty-four patients obtained continuous and acceptable pain relief (VAS 0-2), 26 of them with daily doses of IT-bupivacaine of less than or equal to 30 mg/day (less than or equal to 1.5 mg/h). Higher IT-bupivacaine doses (greater than 60-305 mg/day), not always giving acceptable pain relief, were necessary in 13 patients with deafferentation pain from the spinal cord or brachial or lumbosacral plexuses or pain from the coeliac plexus, or from large, ulcerated mucocutaneous tumours. By combining IT-bupivacaine with IT-morphine, it was possible to use relatively low IT-morphine doses (10-25 mg/day during the first 2 months of treatment) in more than half of the patients. The IT-treatment significantly decreased the total (all routes) opiate consumption and significantly improved sleep, gait and daily activities. For the whole period of observation (6 months), the IT-treatment was assessed as adequate in 3.8%, good in 23.1%, very good in 59.6% and excellent in 13.5% of the cases. Adverse effects of the IT-bupivacaine (paraesthesiae, paresis, gait impairment, urinary retention, anal sphincter disturbances and orthostatic hypotension) did not occur with doses of 2.5-3.0 mg/h (approx. 60-70 mg/day).

Hemodynamic effect of the prone position during anesthesia

Abstract: We studied 21 patients undergoing lumbar spinal surgery under halothane anesthesia on a convex saddle frame, in order to determine the hemodynamic effect of the prone position. A thermodilution pulmonary arterial catheter was placed in 14 patients (Group PA-1: n = 8; and Group PA-2: n = 6), and an inferior vena caval catheter in the remaining seven patients (Group IVC). Group PA-1 and Group IVC patients were placed in the prone position on a convex saddle frame. In the prone position, the cardiac index (CI) decreased significantly from 3.1 +/- 0.5 to 2.5 +/- 0.3 (l.min-1.m-2, mean +/- s.d., P less than 0.01) without accompanying significant changes in the other hemodynamic variables in Group PA-1. The postural change in Group IVC did not exert a significant effect on the inferior vena caval pressure. Group PA-2 were initially placed in the flat prone position on a flat saddle frame, which produced no significant changes in the hemodynamic variables. Then the convex curvature of the frame was adjusted to the grade appropriate for surgery, which produced a significant reduction in CI (from 2.9 +/- 0.3 to 2.4 +/- 0.4, P less than 0.05). We conclude that the prone position itself may not interfere with the circulatory function. The prone position using a convex saddle frame causes significant reductions in CI, but little change in the other hemodynamic variables.

Hemodynamic and catecholamine responses to laryngoscopy with vs. without endotracheal intubation

Abstract: To study the relationship between the intensity of the stimulus exerted against the base of the tongue during direct laryngoscopy and the magnitude of associated hemodynamic and catecholamine responses, a study was conducted in 40 ASA 1 or 11 patients. Laryngoscopy lasting 40 s was performed with a size 3 Macintosh blade connected to a force-displacement transducer. The intensity of the stimulus exerted during laryngoscopy is expressed by the product of its average force (N) and duration (s) and given as impulse in Ns. Highly significant relationships were found between the impulse during laryngoscopy and the maximal hemodynamic and catecholamine responses. Also, when laryngoscopy was followed by orotracheal intubation, significant relationships were found with steeper slopes of the regression lines for systolic blood pressure, heart rate and plasma epinephrine concentrations. A more rapid regression of hemodynamic data was seen in intubated patients, whereas their plasma catecholamine concentrations regressed more slowly. The mechanisms of the responses to laryngoscopy and orotracheal intubation are proposed to be by somato-visceral reflexes. Stimulation of proprioceptors at the base of the tongue during laryngoscopy induces impulse-dependent increases of systemic blood pressure, heart rate and plasma catecholamine concentrations. Subsequent orotracheal intubation recruits additional receptors that elicit augmented hemodynamic and epinephrine responses as well as some vagal inhibition of the heart.

Comparison of standard and high-dose adrenaline in the resuscitation of asystole and electromechanical dissociation.

Abstract: Sixty-eight adults with cardiac arrest (asystole and electromechanical dissociation) were randomly allocated for treatment with standard (1 mg) or high-dose epinephrine (5 mg). If the first dose of adrenaline (1 or 5 mg) failed, standardized advanced life-support was applied in all cases. High-dose adrenaline was associated with higher initial resuscitation success rates (16 of 28) than standard-dose adrenaline (6 of 40), whereas hospital discharge rates were not significantly different between the groups. Blood pressure was significantly higher in the high-dose adrenaline group in comparison to the standard dose at 1 and 5 min after resuscitation. Although high-dose adrenaline appears to improve cardiac resuscitation success, the duration of global cerebral ischaemia seems to determine the ultimate outcome.

Cerebral vasoreactivity and the prediction of outcome in severe traumatic brain lesions.

Abstract: Mean hemispheric blood flow (CBF) was studied in 38 comatose, severely brain-injured patients following intravenous administration of xenon-133. Repeated measurements were performed in order to evaluate cerebral vasoreactivity following a decrease in PaCO2. Simultaneously, arterial-venous oxygen differences (AVDO2) and intracranial pressure (ICP) were measured. An impaired CBF response to hyperventilation (delta CBF/delta PaCO2 less than 1.0) was obtained in 22 patients. Three of 16 patients with preserved CO2-reactivity died because of their brain injuries and 12 patients reached good recovery/moderate disability. In the group of patients with impaired vasoreactivity 11 of 22 patients died and only three patients reached good recovery/moderate disability. The study documents that in patients with severe traumatic brain lesions measurements of cerebral vasoreactivity to hyperventilation give prognostic information that is not obtained by clinical observations or CT-scanning.

The transurethral resection syndrome.

Abstract: The transurethral resection syndrome ("TUR syndrome") is caused by absorption of electrolyte-free irrigating fluid, and consists of symptoms from the circulatory and nervous systems. The clinical picture is inconsistent and the syndrome is easily confused with other acute disorders. Mild forms are common and often go undiagnosed, while severe forms of the TUR syndrome are rare and potentially life-threatening. The pathophysiology is complex but includes four mechanisms: circulatory distress from the rapid absorption of electrolyte-free irrigating fluid, adverse effects of glycine, dilution of the protein and electrolyte concentrations of the body fluids, and disturbance of renal function. The treatment of the TUR syndrome consists of general life support and in specific treatment directed towards hypotension, hyponatraemia and anuria. Methods to lower the uptake of irrigating fluid are widely used and probably reduce the incidence of the TUR syndrome. However, patient safety can be guaranteed only if the absorption is monitored. An irrigating fluid containing tracer amounts of ethanol can be used for this purpose. This permits the uptake of fluid to be indicated by measuring the concentration of ethanol in the patient's exhaled breath.

Allowing pre-operative patients to drink: effects on patients' safety and comfort of unlimited oral water until 2 hours before anaesthesia.

Abstract: The effect of allowing patients unlimited access to oral water in the time up until 2 h pre-operatively was the subject of a randomised, blind, controlled trial. No effect was seen on gastric volume or pH, or on plasma osmolality, and allowing water pre-operatively was associated with a reduction in anxiety in the anaesthetic room.

CT scan in ARDS: clinical and physiopathological insights.

Abstract: C T scan of the lungs of patients with Acute Respiratory Failure (ARF) is increasingly being used despite logistic diiliculties of transporting severely ill patients to the C T scan facilities. To our knowledge, Rommelsheim et al. ( 1 I first reported on C T scan images of the lungs of Adult Respiratory Distress Syndrome (ARDS) patients. In 1986, two reports appeared dealing with ARDS lungs studied by C T scan (2, 3). We would like, i n this review, to focus on the C T scan morphology of ARDS lungs, emphasizing the effects of Positive End Expiratory Pressure (PEEP) and of body position changes. Moreover, we will describe the quantitative approach to the C T scan images we have used to estimate lung weight and regional distribution of gases and tissue in normal and in ARDS lungs. O n the basis of thuse data we will propose a model of evolution from normal to full-blown ARDS lung.

Spinal epidural hematoma following epidural anesthesia versus spontaneous spinal subdural hematoma. Two case reports

Abstract: Two cases of lumbar hemorrhage with subsequent persistent neurologic sequelae are presented and their possible causes are discussed in the context of a literature review: one patient with spontaneous spinal subdural hematoma with no trauma or lumbar puncture and one with spinal epidural hematoma associated with preceding epidural catheterization for postoperative pain relief. The subdural hematoma was associated with a thrombocytopenia of about 90,000/microliters due to intraoperative blood loss. This might have been contributory to the formation or expansion of the hematoma, but it is not convincing since a platelet count of this amount should not lead to spontaneous bleeding. Both patients received low-dose heparin, but since coagulation tests were normal, prolonged bleeding does not appear to be a likely cause, although it cannot be excluded. In conclusion, the reasons for both hematoma remain unclear. With regard to the epidural hematoma and low-dose heparinization, the possible coincidence of spontaneous lumbar hematoma and lumbar regional block should be taken into consideration.

Postoperative patient-controlled analgesia with sufentanil: analgesic efficacy and minimum effective concentrations.

Abstract: Sufentanil has so far seldom been used for intravenous postoperative patient-controlled analgesia (PCA), and the resulting serum concentrations have not yet been determined. Forty ASA I-III patients recovering from major gynecological operations were investigated to evaluate analgesic efficacy, side effects, patient acceptance and threshold concentrations of sufentanil in serum during the early postoperative period, using the On-Demand Analgesia Computer (ODAC). Following an individualized intravenous loading dose of 19.1 +/- 35.7 micrograms (mean +/- 1 s.d.), sufentanil demand doses were 6 micrograms with a concurrent infusion of 1.15 micrograms/h and a maximum hourly dose of 40 micrograms/h; the lockout time was set to 1 min. The duration of PCA was 17.3 +/- 2.1 h. During this time 16 +/- 11 demands per patient were recorded, resulting in an average sufentanil consumption of 131.1 +/- 69.4 micrograms or 7.5 +/- 3.7 micrograms/h (including loading dose). analgesia was mostly judged good. Side effects were only of minor intensity. Sufentanil proved to be about 2.2 to 3.8 times as potent an analgesic as fentanyl when both analgesic effect and duration were considered. Minimum effective sufentanil serum concentration (MEC) as determined by radioimmunoassay varied greatly and could be best described by a log-normal distribution (range less than 0.01-0.56 ng/ml, median 0.024 ng/ml). Intraindividual MEC variability was slightly lower than intersubject variability (76.0 vs. 84.8%). It is concluded that sufentanil is suitable for postoperative PCA. To get into the therapeutic window for analgesia, a serum sufentanil concentration of more than 0.03 ng/ml seems to be necessary.

Injection pain, intubating conditions and cardiovascular changes following induction of anaesthesia with propofol alone or in combination with alfentanil.

Abstract: In a double-blind study, propofol (P) 2-25 mgkg-1 preceded by saline (Sal) or alfentanil (A) 20-30 microgramskg-1 was used for anaesthetic induction in 59 young patients of ASA physical class I or II, premedicated with oxycodone 01 mgkg-1 and atropine 001 mgkg-1 im The patients were randomly allocated to one of the four groups: Group 1 Sal + P25, Group 2 A20 + P25, Group 3 A30 + P25 and Group 4 A30 + P2 Pain on injection of propofol occurred in 67, 36 and 7% of the patients in the Sal + P25, A20 + P25 and A30 + P2 groups, respectively, but not at all in the A30 + P25 group Intubating conditions were assessed as good, moderate, poor or impossible on the basis of jaw relaxation, ease of insertion of the tube and coughing on intubation, each on a three-point scale In impossible cases, suxamethonium was used In the Sal + P25 group, the frequencies of good, moderate, poor and impossible intubating conditions were 0, 38, 8 and 54%, respectively The corresponding figures in the A30 + P25 group were 43, 46, 7 and 14% (P less than 005 between the groups) The other groups did not differ significantly from the Sal + P25 group After injection of propofol, both systolic and diastolic arterial pressures decreased significantly in all other groups, with the exception of diastolic pressure in the Sal + P25 group, whereas heart rate did not differ from the control level After intubation, systolic arterial pressure increased statistically significantly in the Sal + P25 and A30 + P2 groups and diastolic arterial pressure in all other groups with the exception of the A30 + P25 group when compared with the corresponding preceding values(ABSTRACT TRUNCATED AT 250 WORDS)

Transnasal butorphanol: a new method for pain relief in post-cesarean section pain.

Abstract: This study was undertaken to evaluate the efficacy and the safety of transnasal butorphanol (TNB) compared to intravenous butorphanol (IVB) in 186 patients experiencing moderate to severe post-cesarean section pain. Patients were randomly assigned to five groups in a double-blind fashion: Group I (n = 37) received 2 mg IVB, Group II (n = 38) 2 mg TNB, Group III (n = 36) 1 mg TNB followed by a repeat dose of 1 mg TNB at 60 min, Group IV (n = 38) 0.5 mg TNB followed by a repeat dose of 0.5 mg at 60 min, and Group V (n = 37) received placebo. All administrations were double dummy. Pain intensity and relief were noted and the incidence of side effects was recorded. Remedication with the same study drug was allowed up to 72 h. Onset of analgesia was more rapid in the 2 mg IV group compared to the three TN groups: 5 min vs 15 min, respectively. However, the 2 mg and the 1-1 mg TN groups had a longer duration of analgesia, approximately 4.5 h, compared to 3.0 h for the 2 mg IV group (P less than 0.05). Somnolence was dose related and was the most frequent side effect, and was less frequent when the TN dose was divided into 2 doses administered 1 h apart. Multiple doses of TNB and IVB were safe and clinically acceptable up to 3 days at all doses studied. There were no incidences of nasal mucosa irritation, or cardiovascular or respiratory depression. It is concluded that transnasal butorphanol represents a safe and effective alternative to injectable butorphanol for post-cesarean section pain and offers a better and longer duration of analgesia compared to IV butorphanol. The optimum dose seems to be 2 mg TN butorphanol and it is tolerated better when divided into 1 mg increments, given 1 h apart.

Postoperative pulmonary complications and lung function in high-risk patients: a comparison of three physiotherapy regimens after upper abdominal surgery in general anesthesia.

Abstract: The effect of three postoperative regimens of respiratory therapy on pulmonary complications and lung function was compared in high-risk patients. Fifty-one patients were randomized to: 1) conventional chest physiotherapy alone (PHYS), 2) chest physiotherapy and positive expiratory pressure (PEP), or 3) chest physiotherapy with both positive expiratory pressure and inspiratory resistance (RMT). Treatments were given twice daily by a physiotherapist and self-administered. The incidence of postoperative pulmonary complications (PPC) was respectively, 71%, 76% and 65% in the PHYS-, PEP- and RMT-groups. The incidence of PPC requiring treatment with antibiotic, bronchodilator or supplementary oxygen according to the existing clinical practice was 47%, 47% and 29%. The incidence of atelectasis was 65%, 64% and 60% and of pneumonia 29%, 35% and 6%. There was no difference between the groups, except for a tendency to a lower frequency of pneumonia in the RMT-group. Postoperatively forced vital capacity (FVC) decreased to mean 54%, forced expired volume in 1 s to 48% and functional residual capacity to 76% of preoperative values. Arterial oxygen tension (PaO2) declined to mean 8.1 kPa and arterial saturation (SaO2) to 89%. There was no difference between the groups except for FVC, PaO2 and SaO2 (P = 0.008, P = 0.008 and P = 0.002), which showed the least decrease in the RMT-group. None of the regimens could be considered as satisfactory concerning the prevention of PPC, but RMT seemed to be the most efficient. Insufficient self-administration of treatment was probably one of the causes of the overall high incidence of PPC in this study.

Arterial blood gases in patients with acute head injury at the accident site and upon hospital admission.

Abstract: Prior to the start of supportive therapy at the site of the accident, arterial blood samples from 47 patients with acute head injury were taken for blood gas analysis. At the same time, the degree of unconsciousness was assessed using the Glasgow-Coma-Scale. After transport to the hospital, arterial blood gases and the level of unconsciousness were again determined. A very close correlation was found between the initial depth of unconsciousness and the degree of hypercapnia (R = -0.90). Patients with head injury and other multiple injuries did not differ in this report (R = -0.95) from those with isolated head injury. The correlation between PaO2 and the degree of unconsciousness was less well defined, and the results showed a greater degree of scatter (R = 0.54). The acidosis observed resulted mainly from the rise in PaCO2. The absence of any correlation between the base excess and the Glasgow-Coma-Scale levels (R = -0.27) makes a common metabolic derangement unlikely. As a result of intubation and controlled ventilation, the hypercapnia of the comatose patients had been corrected, and a correlation could no longer be found between the Glasgow-Coma-Scale level and the PaCO2. In order to avoid hypoventilation, which carries with it the danger of a rise in intracranial pressure, all patients with severe head injury should be intubated and ventilated as soon as possible after the accident.

Bupivacaine spinal anaesthesia

Abstract: This review presents facts and controversies from the recent literature about bupivacaine in spinal anaesthesia for the benefit of clinical practice

Effect of intradermal injection of saline or a local anaesthetic agent on skin blood flow--a methodological study in man.

Abstract: The influence of intradermal needle insertion and fluid injection on skin blood flow was investigated using laser Doppler flowmetry. Seventeen healthy, young male volunteers participated. Four test sites on each forearm (volar surface) were used in a randomized, double-blind study. Recordings were made at 20, 40, 60 and in Group III also at 90 min after needle insertion or intradermal injection. In Group I (n = 6) different volumes of saline (0.05, 0.1, 0.2, 0.3 and 0.5 ml) were injected, producing an increase in flow, there being no differences between the various volumes. In Group II (n = 4) needle insertions were made using different needle sizes (20 G, 23 G and 30 G), the larger ones being impractical to use. Increases in flow were seen, and were somewhat higher for the larger needles. Group III (n = 12) was studied regarding the effects of three local anaesthetic agents on skin blood flow (0.1 ml, 30 G needle). Injection of bupivacaine 0.75% produced a marked increase in flow, similar to lidocaine 1% but apparently longer lasting. Bupivacaine 0.25% caused less increase in flow, similar to the flow seen with saline. Injections of ropivacaine 0.75% and 0.25%, i.e. in clinical concentrations, caused a decrease in blood flow, this being most marked after 0.25%, indicating a unique flow-decreasing effect of this new local anaesthetic drug.

Tracheal intubation after induction of anaesthesia with thiopentone or propofol without muscle relaxants

Abstract: This study was designed to compare the ease of performing laryngoscopy and endotracheal intubation without muscle relaxants after the induction of anaesthesia with either thiopentone or propofol in 106 patients scheduled for elective surgery. Thiopentone (5 mg/kg) or propofol (2.5 mg/kg), supplemented with lidocaine (1.5 mg/kg) and alfentanil (30 μg/kg), were used in random order for the induction of anaesthesia. Jaw tone, visualisation of the larynx, position of vocal cords, ease of intubation and tolerance of the tracheal tube were assessed. The jaw was relaxed and the vocal cords were immobile/open in most patients in both groups. Visualisation of the larynx was good in 60 and 46%, and intubation was easy in 48 and 22% of the patients given thiopentone and propofol, respectively (P<0.05 between groups for intubation). After induction of anaesthesia with thiopentone or propofol, endotracheal intubation is not recommended without the use of muscle relaxants.

Twitch tension and train-of-four ratio during prolonged neuromuscular monitoring at different peripheral temperatures.

Abstract: In eight healthy patients, the influence of the train-of-four (TOF) response of prolonged neuromuscular monitoring and of different peripheral temperatures was studied during normal core temperature. Anaesthesia was induced and maintained with midazolam-fentanyl and a 70/30% mixture of nitrous oxide and oxygen. The mechanical TOF response of the adductor pollicis muscle (twitch tension and TOF ratio), was recorded simultaneously in both hands using supramaximal TOF stimulation of the ulnar nerve at the wrist. One arm was kept normothermic. The other arm was cooled using cold infusions and cold packings. Skin, muscle and core temperatures were continuously measured. In the normothermic arm (skin temperature greater than 32.0 degrees C), the twitch tension and TOF ratio were unchanged following 130-230 min of continuous nerve stimulation. In the hypothermic arm the twitch tension and TOF ratio showed only minor variations above a skin temperature of 32.0 degrees C (corresponding to a mean muscle temperature of 34.5 +/- 0.3 degrees C). Below a skin temperature of 32.0 degrees C a progressive decrease in TOF response was recorded. A linear relationship was found between skin temperature and TOF response as well as between muscle temperature and TOF response. At a skin temperature of 27.0 degrees C (corresponding to a mean muscle temperature of 30.8 +/- 0.4 degrees C), an approximate 20% reduction in twitch tension and a 10% decrease in TOF ratio were recorded with a considerable interindividual variation. We conclude that prolonged TOF nerve stimulation does not change the mechanical twitch response in patients with a normal central and peripheral temperature. A peripheral skin temperature below 32.0 degrees C with sustained and normal body temperature is, however, associated with changes in both twitch tension and TOF ratio that may be a source of error when evaluating neuromuscular function.

Actions and interactions of mediator systems and mediators in the pathogenesis of ARDS and multiorgan failure.

Abstract: A great variety of mediators and mediator systems are involved in the disturbance of the microcirculation and vascular permeability following polytrauma and sepsis. The locally accentuated, organ related activation and the cooperation of several of these mediators and mediator systems over a longer period of time seem to be responsible for the development of an acute organ failure in terms of ARDS and MOF. Cytokines from macrophages seem to be the determining factors converting a primarily functional and reversible systemic vascular reaction into organ related morphological lesions. This pathogenetic complexity has to be considered in future concepts for therapy and prophylaxis with regard to the hierarchical rank of the mediators involved.

Opioid supplementation to propofol anaesthesia for outpatient abortion: a comparison between alfentanil, fentanyl and placebo

Abstract: One hundred and sixty-four patients scheduled for elective termination of pregnancy under general anaesthesia were randomly assigned to receive one of three different supplements to propofol and oxygen in nitrous oxide anaesthesia: 0.1 mg fentanyl, 0.5 mg alfentanil or placebo. Postoperative pain and nausea, as well as complications during anaesthesia were studied. There were no differences in complications or complaints by surgeons during anaesthesia, and no patient in any group reacted unsatisfactorily to surgery. The patients in the placebo group consumed significantly more propofol during the procedure (P less than 0.001). No differences were seen in time until hospital discharge between the three groups. Complaints about postoperative pain were significantly less frequent among patients receiving fentanyl (P less than 0.01). The number of patients requesting postoperative analgetics, however, did not differ. There was no difference in the frequency of nausea or vomiting, but postoperative pain was found significantly to increase complaints of nausea (P less than 0.01) and also time until hospital discharge (P less than 0.01). In conclusion, opioid supplementation lowered the amount of propofol needed for anaesthesia. Alfentanil 0.5 mg did not improve the postoperative course. Fentanyl 0.1 mg decreased the frequency of postoperative pain without increasing the time to hospital discharge.

The effect of peripheral hypothermia on a vecuronium-induced neuromuscular block.

Abstract: Seven healthy patients were investigated during midazolam-fentanyl nitrous oxide-oxygen anaesthesia. The mechanical twitch response of the adductor pollicis muscle was recorded simultaneously during bilateral supramaximal train-of-four (TOF) stimulation of the ulnar nerves at the wrist. Intense neuromuscular block was evaluated using the post-tetanic count (PTC) method. Core temperature and the peripheral skin temperature of one arm were kept normal and stable. Following cooling of the other arm to a peripheral hand skin temperature of 27 degrees C, vecuronium was administered in a bolus dose of 0.05 mg.kg-1 followed by maintenance doses of 0.02 mg.kg-1. In the hypothermic and the normothermic arm the onset time following the bolus dose was 180 +/- 40 (mean +/- s.d.) seconds and 140 +/- 30 s, respectively, the duration of action was 26.4 +/- 4.5 and 16.5 +/- 4.0 min and the recovery time was 265 +/- 90 and 130 +/- 60 s (P less than 0.01). The time course of action following maintenance doses showed a similar marked difference between the hypothermic and the normothermic arm. In the normothermic arm a close correlation was found between the number of post-tetanic twitches and the time to first response to TOF stimulation. In contrast, in the hypothermic arm the number of post-tetanic twitches showed great variation with a poor correlation to the duration of intense neuromuscular block. It is concluded that the time course of action of a vecuronium-induced neuromuscular block is markedly prolonged during peripheral hypothermia and intense neuromuscular block cannot reliably be assessed using the PTC method at low peripheral temperature.(ABSTRACT TRUNCATED AT 250 WORDS)

Continuous epidural infusion of bupivacaine and morphine for postoperative analgesia after hysterectomy.

Abstract: The analgesic efficacy and side-effects of combined epidural infusion of bupivacaine and morphine, in comparison with these drugs alone, for postoperative analgesia after hysterectomy (60 patients) were evaluated. Before general anaesthesia, all patients had an epidural catheter placed (Th11-12) and 20 ml of 0.5% bupivacaine was injected. In random order, epidural infusion was continued for 24 h with either 0.25% bupivacaine 4 ml- h-1 (BUPI-group), a bolus of 2 mg of morphine followed by morphine 0.2 mg- h-1 (MO-group), or a combination of the two drugs (COMB-group). A urinary bladder catheter was kept for 24 h. Supplementary postoperative pain medications were i.m. morphine 0.1 mg- kg-1 or rectal indomethacin 50 mg, on request. Immediately after awakening from general anaesthesia and transfer to the recovery room, 18/20 of the BUPI-group patients, 17/20 of the MO-group patients and 19/20 of the COMB-group patients were pain-free. In the postoperative evening and the first postoperative morning, the corresponding figures were 7/20 and 10/20 in the BUPI-group, 15/20 and 15/20 in the MO-group, and 18/20 and 15/20 in the COMB-group (postop. evening; P<0.01 BUPI vs. others). The number of patients requiring supplementary analgesics (morphine and indomethacin) during the first 24 h was greatest in the BUPI-group (P<0.01). The number of patients who vomited during the 24-h period was 3 in the BUPI-group, 9 in the MO-group and 5 in the COMB-group. Postoperatively, normal bowel function was restored after 1.9 days in the BUPI-group, 2.2 days in the MO-group and 2.6 days in the COMB-group, on average (P<0.01 BUPI vs. COMB). Recatheterization of the urinary bladder (once) was required in 4 patients in the MO-group and 2 in the COMB-group, but in none of the BUPI-group. It is concluded that although the morphine-containing epidural infusions (6.8 mg 24 h-1) were superior to that containing bupivacaine alone with respect to postoperative analgesia after hysterectomy, the occurrence of disturbing emetic and urinary side-effects made the therapy not totally satisfactory.

Haemodynamic responses and prolongation of QT interval of ECG after suxamethonium-facilitated intubation during anaesthetic induction in children: a dose-related attenuation by alfentanil

Abstract: The haemodynamic response to endotracheal intubation and changes in the QT interval of ECG during anaesthetic induction were studied in 68 healthy children (5.5 years). The children were pretreated double-blindly with either alfentanil 10 micrograms/kg (A10), 25 micrograms/kg (A25), 50 micrograms/kg (A50) or saline (control) (17 children in each group) i.v. 1 min before thiopentone 5 mg/kg. The trachea was intubated after suxamethonium 1.5 mg/kg. Central nervous system excitation was seen in four of 17 and in one of 17 children after alfentanil 50 and 25 micrograms/kg, respectively. After intubation, heart rate increased significantly in the control group, remained at initial levels in the A10 and A25 groups and decreased in the A50 group. A pressor response to intubation was seen in the control and A10 groups. The QT interval was significantly prolonged after suxamethonium in the control and A10 groups, but remained at baseline levels in the A25 and A50 groups. Ventricular ectopic beats were only seen in 2/17 children in the control group. In conclusion, alfentanil 25 microgram/kg is ideal for preventing the haemodynamic response to endotracheal intubation and prolongation of the QT interval, a sign of sympathoadrenal activation, before induction of intravenous anaesthesia in children.

Treatment of neck and shoulder pain in whip-lash syndrome patients with intracutaneous sterile water injections.

Abstract: Ten whip-lash syndrome patients treated with intracutaneous triggerpoint injections with sterile water for pain relief were followed for 2 months. Pain intensity was evaluated with the Visual Analogue Scale (VAS). Eight patients became free from pain (VAS 0) and two patients improved to VAS 2 immediately after the treatment. Nine patients remained free from pain, three of them after one treatment, while six patients needed 2-4 treatments. One patient responded only a few hours after each of three treatments. Remarkably, with the relief of pain mobility was normalised in all patients. The method is suggested to be a first choice in the treatment of not only whip-lash patients but also for most acute and chronic musculo-skeletal triggerpoint pain syndromes.

Effects of glycopyrrolate and atropine on heart rate variability.

Abstract: Analysis of heart rate variability, combined with physiological tests (deep breathing and tilt tests) was used to characterise the effects of atropine and glycopyrrolate on the parasympathetic nervous tone of the heart in healthy male volunteers. The low dose of atropine (120 micrograms) administered as a continuous infusion in 15 min was associated with parasympatomimetic effects estimated by the slowing of the heart rate and an increase of the mean and beat-to-beat heart rate variability. The bradycardia and increase of heart rate variability following infusion of glycopyrrolate (50 micrograms) was less marked and did not differ significantly from that of placebo. The higher doses of atropine (720 micrograms) and glycopyrrolate (300 micrograms) administered as a continuous infusion in 15 min produced an equal vagal cardiac blockade characterised by significant tachycardia and a decrease in overall and beat-to-beat heart rate variability. It is concluded that at low doses the parasympatomimetic action of glycopyrrolate is less marked than that of atropine; and at higher doses only small differences exist between these two muscarinic antagonists in their effects on cardiac vagal outflow, assessed by heart rate and heart rate variability.

A comparison between morphine, meperidine and ketobemidone in continuous intravenous infusion for postoperative relief.

Abstract: Morphine, meperidine and ketobemidone used in continuous i.v. infusion for postoperative pain relief were compared in a double-blind, controlled, prospective study in 81 consecutive consenting adult patients after open-heart surgery, with permission from the hospital ethics committee. During the first postoperative period, the infusion rates were fixed. Later on, when the infusion rate could be regulated according to individual patient needs, the variation in infusion rate was large, in accordance with earlier studies. No significant differences were demonstrated between the three analgesics with respect to efficacy of analgesia or side effects like shivering, nausea or vomiting. Respiratory depression following extubation was not observed. During shivering, there was a significant increase in the arterio-mixed venous difference of oxygen in all groups. The amounts of opioids used were relatively small compared to amounts used in patients following abdominal surgery. When interviewed some days after surgery, 18/74 patients remembered moderate pain and 11 severe pain during the stay in the ICU.

Effects of interpleurally administered bupivacaine 0.5% on opioid analgesic requirements and endocrine response during and after cholecystectomy: a randomized double-blind controlled study.

Abstract: In 30 patients undergoing cholecystectomy, a randomized double-blind saline-controlled study was performed using interpleural 0.5% bupivacaine with or without epinephrine (5 micrograms.ml-1) in combination with 0.8% halothane inspired concentration in oxygen. The aim of the study was to investigate whether interpleural 0.5% bupivacaine could decrease the intraoperative opioid requirements and attenuate the metabolic endocrine response to surgical stress. Patients were randomly allocated to one of three groups: Group 1: 0.5% bupivacaine; Group 2: 0.5% bupivacaine with epinephrine (5 micrograms.ml-1); and Group 3: saline. The interpleural catheter was inserted after induction of anesthesia in the spontaneously breathing patient. The study drug was injected 30 min prior to surgery. Peak plasma bupivacaine concentrations in the respective groups were 1.30 +/- 0.78 and 1.16 +/- 0.48 micrograms.ml-1. In all patients concentrations were below suggested convulsive level. Two patients in Group 1 and two in Group 2 required intraoperative fentanyl (0.1 mg each). In contrast, eight patients in the saline group received an average of 0.21 mg (range 0.1 +/- 0.4 mg) fentanyl (P less than 0.05). Postoperatively, a second dose of the study drug was given. Subsequently, pain was assessed using a visual analog score and a verbal rating scale. Pain scores decreased significantly 30 min after the interpleural injection in both bupivacaine groups and remained unchanged in the saline group (P less than 0.05). Pain management by means of interpleural bupivacaine was successful in 17 of the 20 patients. In the saline group seven out of ten patients needed additional analgesics (P less than 0.05). Cortisol levels increased in response to surgery in all groups: maximum levels in Groups 1, 2 and 3 were: 1.09 +/- 0.29, 1.11 +/- 0.20 and 1.19 +/- 0.16 mumol.l-1, respectively. Plasma glucose concentrations increased significantly in all groups: maximum levels in Groups 1, 2 and 3 were: 7.6 +/- 1.3, 7.3 +/- 1.7 and 8.3 +/- 1.7 mmol.l-1, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Oxygen radicals and lung injury.

Abstract: This article describes the formation of oxygen radicals and their biological effects, especially in relation to lung injury. Various recent experimental data are reviewed. The relationships between hydrostatic effects and permeability effects in producing injury and edema are stressed. Means of prevention and problems related to extrapolation to clinical situations are focused.