The addition of epinephrine increases intensity of sensory block during epidural anesthesia with lidocaine

BACKGROUND AND OBJECTIVES: Little is known about the effect of adding epinephrine to local anesthetic solutions on the intensity of sensory block during epidural anesthesia. This study examined development of sensory block during lumbar epidural anesthesia using a cutaneous current perception threshold (CPT) quantitative sensory testing device. METHODS: Twenty ASA I patients who were randomly divided to receive 10 mL 1% lidocaine with (group E) or without (group P) epinephrine 1:200,000. Current perception threshold at 2,000, 250, and 5 Hz stimulation at the trigeminal (V), ninth thoracic (T9), and second lumbar (L2) dermatomes, and the dermatomal levels of block of light touch, temperature, and pinprick discrimination were measured before and every 5 minutes, until 60 minutes after injection of epidural lidocaine. RESULTS: After epidural administration of lidocaine with epinephrine, all CPT significantly increased at T9 and L2, whereas no increase was detected after epidural plain lidocaine. Areas under the curves, calculated to express overall magnitude and duration of CPT values, were significantly larger in group E than those in group P at 2,000 and 250 Hz at T9. No differences were observed in the maximal levels of loss of cold, pinprick, and touch sensations between both groups. CONCLUSIONS: These results suggest that lumbar epidural anesthesia using 10 mL 1% lidocaine with epinephrine produces a more intense block of both large and small diameter sensory nerve fibers than that with plain lidocaine. It appears, therefore, that the addition of epinephrine improves the quality of sensory block during epidural anesthesia with lidocaine.     

Methylated catecholamine metabolites for diagnosis of neuroblastoma

Assays of urinary catecholamines and their metabolites (HVA, VMA, dopamine) permit biochemical diagnosis of neuroblastoma in approximately 80% of patients. The urinary methylated catecholamine metabolites normetanephrine (NMN), metanephrine (MN), and 3-methoxytyramine (3-MT) were analyzed in 18 patients with neuroblastoma and compared with reference values established for 69 healthy pediatric controls. All 18 neuroblastoma patients had raised urinary excretion of at least one of the three commonly assayed metabolites (HVA, VMA, dopamine). Similarly, raised urinary excretion of a methylated metabolite was noted in all but one of the neuroblastoma patients. The 3-MT level was pathologic in 16 of the 18 patients (89%). In this series, 3-MT assay sensitivity was sufficient to warrant trials on a larger population including comparison with patients considered nonsecretors by routine assay procedures. © 1992 Wiley-Liss, Inc.     

Comparison of epidural pain treatment with sufentanil-ropivacaine infusion with and without epinephrine in children

BACKGROUND: Epidural analgesia provides outstanding pain relief after surgery, but it is also associated with numerous adverse effects. In order to improve postoperative pain management in children we determined whether the use of epinephrine added to epidural sufentanil-ropivacaine infusion reduced drug requirements, the intensity and duration of postoperative pain and the incidence and severity of adverse effects. METHODS: A prospective, randomized, double blind, parallel group study design was used in 61 children. The children were given continuous epidural sufentanil-ropivacaine infusion either with (n=32) or without (n=29) epinephrine for postoperative analgesia. Intravenous ketoprofen, a non-steroid anti-inflammatory drug, was used for all children, and epidural ropivacaine was used for rescue analgesia. The drug consumption, intensity of pain at rest and during activity, and all adverse effects were recorded. RESULTS: : The need for sufentanil (P=0.001) and ropivacaine (P=0.006) was significantly lower in the with-epinephrine group than in the without-epinephrine group. The mean duration of epidural infusion (62 h) was similar in both groups. Four children in the without-epinephrine group were noticed to have a low oxygen saturation (SpO2<90%), and in one child a low respiratory rate (8 breaths min-1). The incidence of pruritus was higher in the without-epinephrine group (P=0.026). CONCLUSION: Both infusions provided effective pain relief, and epinephrine as an adjuvant to continuous epidural sufentanil-ropivacaine infusion seems to be useful in children.     

The use of high doses of adrenaline in paediatric cardiac resuscitation

Adrenaline has been used in cardiac resuscitation for many years, yet until recently its mechanism of action and optimal dosage remained poorly investigated or understood. Recent guidelines suggest the use of higher doses of adrenaline at an early stage in paediatric resuscitation. This paper examines the use of adrenaline in paediatric resuscitation and studies the arguments in favour of using higher doses than previously accepted.     

Do anxiety patients with or without frequent panic attacks differ in their respnse to stress?

To evaluate different responses in norepinephrine (NE), epinephrine (E), heart rate (HR), electrodermal activity (EDA) and subjective ratings to a ‘neutral’ and a ‘patient-specific’ stressor we compared nine anxiety patients with three or more panic attacks during the past week, 10 patients with no panic attacks during the past week and 10 controls, at baseline as well as during two stressors: a videotape containing horror scenes and a tape showing a patient having a panic attack. Both patient groups exhibited higher base levels of panicky feelings, anxiety, nervousness, NE and EDA. The panic attack tape proved a stressor that induced significantly more pronounced increases in subjective bodily symptoms, NE, E and EDA in the patients with three or more panic attacks. Our data suggest that patients with frequent panic attacks show higher reactivity to a stimulus that recalls previous experiences of panic attacks.     

24 Hour changes in catecholamine content of rat thyroid and submaxillary glands

Summary The occurrence of diurnal rhythmicity in tissue norepinephrine (NE), epinephrine (E) and dopamine (DA) levels of rat thyroid and submaxillary glands was assessed in animals killed at eight time intervals during a 24 hour period. In both tissues significant peak values of NE content were found at the third hour of dark onset (at 23:00 h). Additionally a minimum of NE content of thyroid gland was apparent in rats killed at the fifth hour of photophase (at 11:00 h). As in the case of NE, peak values of E content were found during the scotophase in both tissues examined. In contrast, DA levels exhibited no diurnal rhythmicity in the rat thyroid gland, and an early rise at the beginning of the photophase in the submaxillary glands. These results support an activation of the sympathetic nervous system innervating the thyroid and submaxillary glands at the beginning of the scotophase. Tissue DA levels do not resemble the activity of peripheral sympathetic nerves in the tissues examined.This study was supported by grants PID 3-078500 and PID 3-0667500 from the Consejo Nacional de Investigaciones Clientificas y Técnicas, Argentina.     

硬膜外试验剂量在老年人麻醉中的可靠性探讨

将70例硬膜外麻醉病人分为60岁以下组和60岁以上组(老年组)。按自身交叉随机设计原则在硬膜外或静脉内注射2%利多卡因3ml(含肾上腺素15μg)。静注后老年组和非老年组心率分别增快18.8±8.60beat/min 和29.3±16.64beat/min(P<0.01);分别有11例和32例病人有自觉症状(P<0.01)。单独据心率或症状判断试验液是否误注血管,准确性分别为老年组88.5%或84.25,非老年组94.2%或95.7%;联合判断其准确率分别为90.0%和95.7%。提示硬膜外试验剂量在老年人麻醉中的可靠性较差。     

The hepatic alpha 1-adrenergic receptor

Since the relatively recent advent of radioligand binding techniques, it has been possible to directly identify and characterize hepatic adrenergic receptors as well as study their physiological regulation. While it is now clear that alpha 1-adrenergic receptors constitute the major population of hepatic adrenergic receptors and are primarily responsible for the actions of catecholamines in liver, relatively little is known about the molecular mechanisms underlying alpha 1-responses. Recent results suggest that guanine nucleotides may be implicated in the transmission of the hormonal signal from the hepatic alpha 1-receptor to its effectors in a manner analogous to that described for adenylate cyclase-linked receptors. The lack of an easily measurable proximal membrane response for the alpha 1-receptor has been a severe handicap in our understanding of the mechanism of transmission of the hormonal signal. It is likely that until such a response is defined, alpha 1-adrenergic research will continue to lag behind research on the beta-adrenergic receptor.     

Regional changes in adrenaline of rat brain during development

The changes of adrenaline during development were studied in several regions of rat brain. Adrenaline is present in hypothalamus, medulla oblongata-pons, midbrain, and cerebellum. Adult levels are attained between 15 and 30 days, depending on the region. These adult levels are attained earlier in the caudal regions than in the rostral regions. In cerebellum and medulla oblongata-pons, the adrenaline content reaches a maximum at 15 days which is close to the time in which the levels of phenylethanolamine-N-methyltransferase (PNMT) reach their maximum. In midbrain and hypothalamus, there is a lag between the adult levels of adrenaline and the activity of PNMT. Adrenaline reaches adult levels at 25 days in midbrain and at 30 days in hypothalamus, while PNMT activity adult levels are attained at 15 days.     

Hypothalamic sites for cardiovascular and sympathetic modulation by prostaglandin E2

Prostaglandin E₂ (PGE₂, 0.5–5 nmol/kg) injected into the lateral cerebral ventricle of the rat increased the systemic blood pressure and heart rate in a dose dependent manner. These effects were accompanied by increases in plasma norepinephrine and epinephrine concentration. Injection of the low dose of prostaglandin E₂ into discrete hypothalamic nuclei induced a marked increase in heart rate, a moderate increase in the arterial blood pressure and a significant elevation of plasma norepinephrine level. This study suggests a possible central role for PGE₂ in modulation of cardiovascular dynamics and sympathetic nervous activity.