No morphine sparing effect of ketamine added to morphine for patient-controlled intravenous analgesia after uterine artery embolization.

BACKGROUND: Pain following embolization of the uterine arteries (UAEs) is variable and may be very severe requiring large doses of parenteral opioids for relief. The present study tested the hypothesis that the addition of ketamine to i.v. patient-controlled morphine reduces the amount of morphine required for pain-control during the first 24 h after UAE embolization. METHODS: Fifty-six patients undergoing UAE embolization for treatment of symptomatic uterine leiomyomata were randomized to receive either 2 mg/ml of morphine (Control group, n=30) or 2 mg/ml of both morphine and ketamine (Ketamine group, n=26) by i.v. patient-controlled analgesia (IV-PCA). Pump settings were bolus dose 1 ml, lockout 10 min, no background infusion. In addition, all patients received diclofenac and acetaminophen for pain relief. Pain scores, morphine consumption and adverse events like nausea, vomiting, itching, visual disturbances, anxiety, dreaming and hallucinations, if any, were recorded for 24 h after embolization. RESULTS: The mean +/- SD 24-h consumption of patient-controlled morphine was 38.3 +/- 21.0 mg in the Ketamine group vs. 33.3 +/- 18.3 mg in the Control group (NS). The difference between the means was 5.0 mg (95% confidence interval: -5.7; 15.6). One patient in the Ketamine group vs. none in the Control group experienced auditory hallucinations. CONCLUSION: Studying an unselected group of patients undergoing embolization of the UAEs for treatment of symptomatic uterine leiomyomata under conditions of basal analgesia with acetaminophen and diclofenac, we failed to demonstrate any morphine-sparing effect of IV-PCA ketamine and morphine compared with IV-PCA morphine alone.

Kinesiophobia is associated with pain intensity but not pain sensitivity before and after exercise: an explorative analysis.

OBJECTIVE: To compare clinical pain intensity, exercise performance, pain sensitivity and the effect of aerobic and isometric exercise on local and remote pressure pain thresholds (PPTs) in patients with chronic musculoskeletal pain with high and low levels of kinesiophobia. DESIGN: An experimental pre-post within-subject study. SETTING: An exercise laboratory in a multidisciplinary pain clinic. PARTICIPANTS: Fifty-four patients with chronic musculoskeletal pain. INTERVENTIONS: Acute aerobic and isometric leg exercises. MAIN OUTCOME MEASURES: Clinical pain intensity (numerical rating scale, range 0 to 10), Tampa Scale of Kinesiophobia, aerobic and isometric exercise performances (intensity and maximal voluntary contraction), and PPTs at local and remote body areas before and after exercise conditions. RESULTS: Patients with a high degree of kinesiophobia demonstrated increased pain intensity compared with patients with a low degree of kinesiophobia [high degree of kinesiophobia: 7.3 (1.6) on NRS; low degree of kinesiophobia: 6.3 (1.6) on NRS; mean difference 1.0 (95% confidence interval 0.08 to 1.9) on NRS]. Aerobic and isometric exercises increased PPTs, but no significant group differences were found in PPTs before and after exercise. CONCLUSIONS: Clinical pain intensity was significantly higher in patients with a high degree of kinesiophobia compared with patients with a low degree of kinesiophobia. Despite a difference in isometric exercise performance, the hypoalgesic responses after cycling and isometric knee exercise were comparable between patients with high and low degrees of kinesiophobia. If replicated in larger studies, these findings indicate that although kinesiophobic beliefs influence pain intensity, they do not significantly influence PPTs and exercise-induced hypoalgesia in patients with chronic musculoskeletal pain.

Isometric exercises reduce temporal summation of pressure pain in humans.

BACKGROUND: Aerobic and isometric exercises are known to decrease pain sensitivity. The effect of different types of exercise on central mechanisms such as temporal summation of pain (TSP) is less clear. This study hypothesized that both aerobic and isometric exercises would increase pressure pain tolerance (PTT) and reduce TSP with greater effects after higher-intensity exercises. METHODS: One hundred thirty-six healthy subjects (18-65 years; 68 women) participated in two randomized crossover experiments with trials on two different days. PTT and TSP were assessed before and after bicycling and a non-exercise condition (experiment 1), and after low- and high-intensity bicycling and low- and high-intensity isometric arm and leg exercises with the dominant arm/leg (experiment 2). PTT and TSP were assessed before and after each exercise condition on the non-dominant arm and leg by computer-controlled cuff algometry. TSP was assessed by visual analogue scale (VAS) scores of the pain intensity during sequential cuff-pressure stimulation at the pain tolerance intensity related to that specific time point. RESULTS: In experiment 1, bicycling, but not the non-exercise condition, slightly increased PTT when assessed at the leg (p < 0.05). In experiment 2, isometric arm and leg exercises increased PTT and reduced VAS scores to sequential stimulation at the arm and leg (p < 0.05). No systematic difference was found between low- and high-intensity exercises. CONCLUSIONS: Different manifestations of hypoalgesia between aerobic and isometric exercises were found. Isometric exercises reduced temporal summation illustrating the potential for exercise as a rehabilitation procedure also targeting the central mechanisms.

Plasma levels of atrial natriuretic peptides during pregnancy and post partum in the rat.

Plasma concentrations of atrial natriuretic peptides (ANP) in female Wistar rats were measured by radioimmunoassay at oestrus, during pregnancy, during parturition and between 3 h and 4 days post partum. Concentrations of ANP in rats on days 10, 15 and 17 of pregnancy were not significantly different from those in non-pregnant animals in oestrus (32.5 +/- 2.2 pmol/l; mean +/- S.E.M., n = 9), but levels near term (days 20 and 21 of pregnancy) were reduced by approximately 50%. However, plasma concentrations of ANP at 6, 12 and 24 h post partum were approximately twice those of non-pregnant animals in oestrus, but returned to normal levels within 4 days after parturition. Maternal plasma volume increased significantly during pregnancy, and fell 15-20% 6-24 h post partum. These results suggest that the relationship between plasma volume and the plasma concentration of ANP is reset during pregnancy and changes rapidly post partum. The results do not necessarily, however, imply any changes in the relationship between atrial pressure and the concentration of ANP.

Inhibition of rat uterine contractions by rat and human CGRP.

Effects of rat and human calcitonin gene-related peptide (r alpha CGRP and h beta CGRP, respectively) upon uterine contractile force were investigated using uterine horns from nonpregnant rats, r alpha CGRP and h beta CGRP were equipotent (pD2 = 8.85-9.09) in inhibiting spontaneous and electrically evoked uterine contractions. r alpha CGRP was relatively ineffective in inhibiting potassium-induced contractures of preparations from stilbestrol-pretreated rats. The use of selective antagonists established that r alpha CGRP did not release prostanoids, or release or act at receptors for catecholamines and histamine. The effects of the peptides were not significantly modulated by estrogen levels since pD2 values were similar (8.56-8.86) in field-stimulated preparations from rats in proestrus/estrus or metestrus/diestrus.

Fenoterol and salbutamol actions on guinea-pig myometrium: effects of ovarian steroids.

Responses of isolated preparations of longitudinal myometrium from the guinea-pig to fenoterol, salbutamol and isoprenaline were examined. Virgin adult guinea-pigs were treated (i) with oestradiol cypionate 20 micrograms/kg s.c. thrice weekly for two weeks; or (ii) as in (i) plus progesterone 3 mg/animal for the last four days. Other animals (diestrous; cycle days 6-10) were untreated. The order of potency of the agonists in inhibiting field stimulation-induced contractions of the preparations (isoprenaline greater than or equal to fenoterol greater than salbutamol) indicated interaction with beta 2-adrenoceptors. Oestrogen treatment enhanced the potency of isoprenaline 5-fold. Treatment with oestrogen plus progesterone enhanced the potency of all agonists 10- to 30-fold, and increased the mean maximum response to salbutamol. The mean pKD values for displacement by fenoterol of binding of (-)-[125I]cyanopindolol to membrane preparations from animals in both treatment groups were 5.57-5.92. These results raise the possibility that progesterone may enhance the coupling of beta 2-adrenoceptors to transduction mechanisms in the longitudinal myometrium from oestrogen-primed guinea-pigs.

[Paracetamol. New knowledge about pharmaceutical action, analgesic relief and anti-inflammatory effects compared with non-steroidal anti-inflammatory effect]. / Paracetamol. Ny viden om virkningsmekanismer samt smertelindrende og antiinflammatorisk effekt sammenlignet med ikke-steroide antiinflammatorika.

Paracetamol is usually termed a peripheral analgesic from the common belief that its site of action is near the injury. In this review a possible central action is summarised. Furthermore the analgesic effect of paracetamol is compared to non-steroidal anti-inflammatory drugs and the possible anti-inflammatory effect of paracetamol is discussed.

[Work and safety conditions in transportation of patients between hospitals in Denmark]. / Arbejds- og sikkerhedsforhold ved interhospitale patienttransporter i Danmark.

Questions on the safety and comfort for the staff on interhospital transports were put to assistant matrons of anaesthesiological wards in Denmark. The investigation shows that ambulances leave with unattached equipment on the floor or in the patient's bed and that the staff either sit without safety belts or stand up beside the patient during transport. The ambulance interior is organized in such a way that the staff's working positions are negatively affected.

[Patient categories and use of staff in transportation of patients between hospitals in Denmark]. / Patientkategorier og personaleforbrug ved patienttransport mellem hospitaler i Danmark.

Questions about how many and how far patients are transported from one hospital to another in Denmark were put to assistant matrons of anaesthesiological wards. They were also asked about what type of patients they accompanied on interhospital transports. Every year roughly 4500 patients are moved from one hospital to another. The patients are mostly neurosurgical and paediatric patients. Apart from the nurse from the anaesthesiological ward, there is usually also a doctor from another ward who accompanies the patient.

[Spinal analgesia in young patients using the Whitacre needle G25]. / Spinalanalgesi til unge mennesker med Whitacre-kanyle G25.

A material of 100 patients aged 20-50 years was assessed after spinal analgesia with the Whitacre cannula G 25. None of the patients developed post-dural-puncture headache.

[The effect of suxamethonium on intracranial pressure]. / Suxamethons virkning på det intrakraniale tryk.

The literature concerning the effect of suxamethonium on intracranial pressure in animals and in humans is presented. The studies have not provided firm indications that suxamethonium per se increases the intracranial pressure. Patients with increased intracranial pressure who are to receive suxamethonium should first be deeply anaesthetized and given a defasciculating dose of a non-depolarizing blocker.

[Prospective registration of injuries to the staff during interhospital patient transportation]. / Prospektiv registrering af personaleskader under interhospitale patienttransporter.

A prospective registration was carried out of all injuries or near-injuries to hospital staff that took place while the staff were engaged in transporting patients between hospitals. A total of 480 transports were registered over one year. Of these, 146 took place as emergencies, 60 with police escort. Four accidents to staff were registered (0.86% of all transports), where the staff in two cases suffered light bruising. Equipment that is brought along in order to treat and monitor patients should be able to be securely fastened during transport with a view to optimizing safety during transportation for patients and staff.

Influence of altered thyroid state on the inotropic potency of isoproterenol--studies with isolated rat left atria paced at different frequencies.

The influence of thyroid status upon the inotropic effect of isoproterenol has been examined using left atrial preparations isolated from hypothyroid, control (untreated), and hyperthyroid rats. Atria were paced at 5 Hz with submaximal field pulses, and isoproterenol was added cumulatively. Mean maximum inotropic responses to isoproterenol were 1.4 mN (hypothyroid), 1.2 mN (control), and 0.3 mN (hyperthyroid). Analysis of log concentration-fractional response curves revealed that isoproterenol was approximately 10 times less potent in preparations from hypothyroid rats. In preparations from hyperthyroid rats, the potency of isoproterenol was similar to that observed in control preparations. These results cast doubt upon the functional significance of the increased responsiveness to isoproterenol observed in other studies in which atria were paced at low frequencies. When applied at a concentration approximating the appropriate EC50 to atria paced at varying frequencies (1, 3, 5, and 5.8 Hz), isoproterenol enhanced contractile force developed in response to stimulation at the lower frequencies in atria from hypothyroid rats, and depressed the response of atria from hyperthyroid rats to stimulation at the higher frequencies.

Effect of changes in thyroid state on atrial alpha- and beta-adrenoceptors, adenylate cyclase activity, and catecholamine levels in the rat.

The effects of altered thyroid state on catecholamine levels, adrenoceptor agonist potencies, and adenylate cyclase activity have been investigated using rat atria in an attempt to determine any correlation between thyroid-induced changes in these parameters. Hypothyroidism was associated with decreased growth rate, heart rate and weight, and hypertrophy of the thyroid gland; norepinephrine concentration in combined atria was also reduced. Hyperthyroid rats displayed tachycardia and marked cardiac hypertrophy, but unchanged atrial norepinephrine concentration. Measurements of inotropic potencies of phenylephrine, norepinephrine, and isoproterenol using paced left atria from hypothyroid rats indicated a possible increase in number, but not in affinity, of alpha-adrenoceptors relative to beta-adrenoceptors. The reverse was observed in hyperthyroidism. However, similar changes were not obtained when chronotropic responses to the three amines were examined using spontaneously beating right atrial preparations. Our results suggest that only in the hypothyroid state do alpha-adrenoceptors contribute significantly to the positive inotropic response to catecholamines. Adenylate cyclase activation by isoproterenol and fluoride ion was reduced in atrial membrane preparations from hypothyroid rats. Taken together, these results suggest that thyroid state modifies both pre- and post-junctional adrenergic mechanisms in rat atria.

Influence of altered thyroid state on the interval-strength relationship of paced left atria of rats.

Rats were treated with methimazole or thyroxine to render them either hypothyroid or hyperthyroid. Left atria from these animals and from control, untreated rats were isolated, placed in organ baths, and paced by direct electrical stimulation delivered via a punctate electrode. Contractile responses to trains of stimuli at 0.01-6 Hz were recorded isometrically. Atria from methimazole-treated rats required less voltage to elicit submaximal contractions; these were greater in magnitude and duration than those recorded from control preparations. The reverse was observed for preparations from hyperthyroid rats. Thyroid state had a marked influence upon the pattern of contractions elicited by trains of stimuli at varying frequencies. Atria from control rats displayed a typical negative interval-strength relationship, i.e., a decrease in contractile amplitude as the interval between stimuli in a train was decreased. This negative relationship was more pronounced in left atria from hypothyroid rats. In preparations from hyperthyroid rats, increases in stimulation frequency resulted in elevations in contractile amplitude. These observations are discussed in the light of known actions of thyroid hormone upon cardiac contractile mechanisms.

Actions of some autacoids and peptides, including relaxin, on costo-uterine muscle from rats.

1. The actions of angiotensin II, bradykinin, oxytocin, arginine vasopressin, relaxin, serotonin and the prostaglandins E2 and F2 alpha were examined on preparations of costo-uterine muscle from stilboestrol-treated rats. 2. All the agonists, except relaxin, when used in concentrations which contract the rat uterus, also produced contractions of costo-uterine muscles. Concentration-response curves were steep and maximal responses to the agonists were comparable. The negative log molar EC50 values were: serotonin, 6.5; angiotensin II, 8.8; bradykinin, 8.4; PGE2, 8.3; PGF2 alpha, 7.1. The EC50 values (units/L) for oxytocin and vasopressin were 4.4 and 2.7 respectively. 3. Indomethacin (2.8 or 5 mumol/L) did not decrease the contractile effects of the peptides or serotonin. The effects of serotonin were reduced, but not reversed, by methysergide (0.94 mumol/L). 4. Porcine relaxin inhibited field stimulation-induced contractions of costo-uterine muscle and uterine horns from immature rats pretreated with oestradiol cypionate and from stilboestrol-treated mature rats. It was much less potent, and its effects were less clearly concentration-related, on costo-uterine muscle. 5. The inhibitory effects of relaxin on the uterus were unaffected by propranolol (1 mumol/L), confirming that on this tissue relaxin acts independently of the release of catecholamines. Progesterone (30 mumol/L) was also without effect on the action of relaxin on the uterus. 6. These results taken together indicate that the costo-uterine muscle of the rat: (i) contracts in response to serotonin and the peptides angiotensin II, arginine vasopressin, bradykinin and oxytocin independently of the release of the contractile prostaglandins F2 alpha and E2; and (ii) in contrast to the uterus, may lack a significant population of receptors for relaxin.(ABSTRACT TRUNCATED AT 250 WORDS)

Beta-adrenoceptors in circular and longitudinal myometrial membranes and in lung membranes from dioestrous and post-partum guinea-pigs.

1. We have examined the binding of (-)[125]-cyanopindolol ((-)[125I]-CYP) to membranes prepared from uterus and lung of dioestrous and post-partum (1-6 days) guinea-pigs. 2. The densities of beta-adrenoceptor binding sites in circular and longitudinal myometrium from dioestrous animals were similar, and approximately one-eight of those in the lung. Ascorbate and ethylenediaminetetraacetic acid in the incubation medium did not affect binding. 3. The numbers and affinities of beta-adrenoceptor binding sites in both myometrial layers and in lung parenchyma from post-partum animals were similar to those in corresponding tissues from dioestrous animals. 4. The distribution of beta-adrenoceptor binding sites in the post-partum uterus was examined using receptor autoradiography. Binding to circular and longitudinal muscle layers and to the endometrium was inhibited by (-)-propranolol (1 mumol/l), by the beta 2-adrenoceptor selective antagonist ICI 118,551 (70 nmol/l), but not by the beta 1-adrenoceptor selective antagonist CGP 20712A (100 nmol/l), indicating that the beta-adrenoceptor present was of the beta 2-subtype. 5. The ability of isoprenaline to compete for (--)[125]-CYP binding sites in uterine membranes from post-partum animals was approximately twice that in corresponding preparations from dioestrous animals. 6. Changes in the numbers or affinity of beta 2-adrenoceptors cannot account for the marked and selective enhancement of the actions of sympathomimetic amines at beta-adrenoceptors previously observed in longitudinal myometrium taken from post-partum guinea-pigs. It is suggested that enhancement of later steps in the chain of events between beta-adrenoceptor occupancy and uterine relaxation, and/or a decrease in the contribution of alpha-adrenoceptors to the net effect of the amine might provide alternative explanations.

Uterine contractility and actions of catecholamines in longitudinal and circular uterine layers from ovariectomised guinea-pigs: the effects of ovarian steroids.

The influence of ovarian steroids upon responses to electrical stimulation and to activation of adrenoreceptors in field-stimulated preparations of longitudinal and circular myometrium from ovariectomised guinea-pigs has been investigated. Adult virgin guinea-pigs were bilaterally ovariectomised and were treated two weeks later with thrice-weekly injections of oestradiol cypionate for two weeks, or treated as in then given oestradiol cypionate and progesterone for a further four days. Control groups of bilaterally ovariectomised and sham ovariectomised animals remained untreated. Both myometrial layers from untreated ovariectomised guinea-pigs were atrophied. Responses to field stimulation in the circular myometrium were much smaller than those in the longitudinal layer. Steroid pretreatment, most notably treatment with oestradiol and progesterone, were associated with decreased and increased responsiveness to electrical stimulation in the circular and longitudinal myometrial layers respectively. Adrenaline and noradrenaline were consistently excitatory on preparations of circular myometrium from ovariectomised animals. Responses comprised either enhancement of electrically-evoked contractions, or, with the higher concentrations, the appearance of rapid contractions superimposed upon an increase in basal tone. The latter effects were also evident in preparations of circular myometrium from sham operated animals. In preparations of longitudinal myometrium from untreated ovariectomised animals noradrenaline consistently and adrenaline usually caused a simple enhancement of the magnitude of the evoked contractions. Phentolamine reduced the excitatory effects of both amines in both layers. In circular myometrium from the oestrogen-treated group both catecholamines produced phentolamine-sensitive enhancement of electrically-evoked contractions, but did not cause high frequency contractions or increased tonus. Noradrenaline and adrenaline produced qualitatively similar phentolamine-sensitive effects in preparations of longitudinal myometrium from this group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenoreceptor-mediated responses in the isolated portal vein of the hypothyroid rat.

1 The effect of hypothyroidism, induced by methimazole, upon the response of the isolated portal vein of the rat to adrenoceptor agonists and antagonists, to angiotensin II and to papaverine has been investigated. 2 The positions and maxima of log doses-response curves, to the vasoconstrictor agonists, noradrenaline and angiotensin II, and to the vasodilator agonists isoprenaline and papaverine, were unaffected by methimazole treatment. 3 The alpha-adrenoreceptor antagonist phentolamine competitively inhibited the effects of noradrenaline to a similar extent in preparations from control and hypothyroid animals. The competitive antagonism of isoprenaline by the beta-adrenoreceptor antagonist propranolol was similarly unaffected by hypothyroidism. 4 These results taken together indicate that hypothyroidism is without significant effect upon either the properties of postjunctional alpha- and beta-adrenoreceptors in the rat portal vein, or upon the reactivity of this blood vessel to the vasoactive agonists studied.

The influence of neuronal uptake upon the relative potencies of agonists acting at prejunctional alpha 2-adrenoceptors in the rat isolated vas deferens.

The effects of inhibition of neuronal uptake upon the potency of the alpha-adrenoceptor antagonist phentolamine and upon the potencies of several agonists which produce inhibition of twitches evoked by field stimulation of the prostatic third of the rat vas deferens are described. In doses producing similar inhibition of the uptake of 3H-noradrenaline, cocaine produced a greater inhibition of the effects of (-)-noradrenaline than did desipramine or diphenhydramine. Cocaine differentially potentiated the effects of the sympathomimetic amines used such that the relative order of agonist potency was changed from xylazine greater than (-)-adrenaline greater than (+)-noradrenaline greater than (-)-metaraminol greater than or equal to (-)-noradrenaline greater than or equal to dopamine, to xylazine greater than (-)-adrenaline greater than (-)-noradrenaline greater than (-)-metaraminol greater than dopamine greater than or equal to (+)-noradrenaline. Prazosin enhanced and yohimbine reduced the twitch inhibition produced by (-)-noradrenaline in the absence of uptake blockers. In contrast, phentolamine had little effect upon the position of the log concentration curve for (-)-noradrenaline except when uptake was inhibited. These experiments demonstrate the marked influence of neuronal uptake upon estimates of the relative potencies of agonists activating alpha 2-adrenoceptors, and upon the estimate of the potency of phentolamine as an antagonist of noradrenaline at these receptors in this densely innervated tissue.