Effects of two fentanyl constant rate infusions on thermal thresholds and plasma fentanyl concentrations in awake cats

Abstract Background The present study aimed to collect pharmacokinetic data of a methadone continuous rate infusion (CRI) and to investigate its effect on mechanical and thermal nociceptive thresholds. Seven, 47 to 54 months old beagle dogs, weighing 9.8 to 21.2 kg, were used in this experimental, randomized, blinded, placebo-controlled crossover study. Each dog was treated twice with either a methadone bolus of 0.2 mg kg− 1 followed by a 0.1 mg kg− 1 h− 1 methadone CRI (group M) or an equivalent volume of isotonic saline solution (group P) for 72 h. Mechanical and thermal thresholds, as well as vital parameters and sedation were measured during CRI and for further 24 h. Blood samples for methadone plasma concentrations were collected during this 96 h period. Results Percentage thermal excursion (%TE) increased significantly from baseline (BL) until 3 h after discontinuation of CRI in M. Within P and between treatment groups differences were not significant. Mechanical threshold (MT) increased in M until 2 h after CRI discontinuation. Bradycardia and hypothermia occurred in M during drug administration and dogs were mildly sedated for the first 47 h. Decreased food intake and regurgitation were observed in M in five and four dogs, respectively. For methadone a volume of distribution of 10.26 l kg− 1 and a terminal half-life of 2.4 h were detected and a clearance of 51.44 ml kg− 1 min− 1 was calculated. Effective methadone plasma concentrations for thermal and mechanical antinociception were above 17 ng ml− 1. Conclusion A methadone CRI of 0.1 mg kg− 1 h− 1 for 3 days after a loading dose results in steady anti-nociceptive effects in an acute pain model in healthy dogs. Main side effects were related to gastrointestinal tract, hypothermia, bradycardia and sedation.

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Constant-Rate Feed Device. A Reply to Comment

Analytical Chemistry ◽

10.1021/ac60043a602 ◽

1950 ◽

Vol 22 (7) ◽

pp. 956-956 ◽

Cited By ~ 1

Author(s):

Lester Lundsted

Keyword(s):

Constant Rate ◽

Feed Device

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The effect of a dexmedetomidine constant rate infusion on cardiopulmonary function and colonic blood flow in anesthetized, experimentally endotoxemic horses

Veterinary Anaesthesia and Analgesia ◽

10.1016/j.vaa.2020.07.017 ◽

2020 ◽

Vol 47 (6) ◽

pp. 855.e6

Author(s):

R. Hector ◽

M. Rezende ◽

B. Nelson ◽

E. Monnet

Keyword(s):

Blood Flow ◽

Constant Rate Infusion ◽

Cardiopulmonary Function ◽

Constant Rate ◽

Colonic Blood Flow ◽

Rate Infusion

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Counterregulation of insulin-induced hypoglycaemia in primary hypothyroidism

Acta Endocrinologica ◽

10.1530/acta.0.1110516 ◽

1986 ◽

Vol 111 (4) ◽

pp. 516-521

Author(s):

Nina Clausen ◽

Per-Eric Lins ◽

Ulf Adamson ◽

Bertil Hamberger ◽

Suad Efendić

Keyword(s):

Growth Hormone ◽

Insulin Infusion ◽

Primary Hypothyroidism ◽

Constant Rate Infusion ◽

Counterregulatory Hormones ◽

Insulin Metabolism ◽

Hormonal Responses ◽

Glucose Levels ◽

Constant Rate ◽

Rate Infusion

Abstract. Hypothyroidism has been alleged to modulate insulin action and influence the secretion of growth hormone and catecholamines. We recently investigated the influence of hypothyroidism on glucose counterregulatory capacity and the hormonal responses to insulin-induced hypoglycaemia in 6 patients with primary hypothyroidism (age 32–52 years, TSH-values 66–200 mU/l). Hypoglycaemia was induced in the hypothyroid state and again when the subjects were euthyroid. After an overnight fast a constant rate infusion of insulin (2.4 U/h) was given for 4 h. Glucose was measured every 15 min and insulin, C-peptide, glucagon, epinephrine, norepinephrine, growth hormone and cortisol every 30 min for 5 h. During insulin infusion somewhat higher concentrations of the hormone were obtained in the hypothyroid state and simultaneously glucose levels were 0.5 mmol/l lower. As expected, basal norepinephrine levels were higher in hypothyroidism. However, no increase in circulating norepinephrine during hypoglycaemia was registered in the two experiments. The responses of counterregulatory hormones showed an enhanced response of cortisol, similar responses of growth hormone and epinephrine while the glucagon response was paradoxically impaired. Our findings suggest that hypothyroidism alters insulin metabolism, and that the glucagon response to hypoglycaemia is impaired in this condition.

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Recent Studies of Tire Braking Performance

Tire Science and Technology ◽

10.2346/1.2167159 ◽

1973 ◽

Vol 1 (2) ◽

pp. 121-137 ◽

Cited By ~ 1

Author(s):

J. L. McCarty ◽

T. J. W. Leland

Keyword(s):

Steady State ◽

Rapid Cycling ◽

Single Cycle ◽

Steering Angle ◽

Slip Ratio ◽

Factors Affecting ◽

Braking Performance ◽

Constant Rate

Abstract The results from recent studies of some factors affecting tire braking and cornering performance are presented together with a discussion of the possible application of these results to the design of aircraft braking systems. The first part of the paper is concerned with steady-state braking, that is, results from tests conducted at a constant slip ratio or steering angle or both. The second part deals with cyclic braking tests, both single cycle, where brakes are applied at a constant rate until wheel lockup is achieved, and rapid cycling of the brakes under control of a currently operational antiskid system.

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CARPENTER GLASS SEALING 52

Alloy Digest ◽

10.31399/asm.ad.fe0101 ◽

1993 ◽

Vol 42 (10) ◽

Keyword(s):

Thermal Expansion ◽

Physical Properties ◽

Tensile Properties ◽

Constant Rate

Abstract CARPENTER GLASS SEALING 52 alloy has a virtually constant rate of thermal expansion to 1050 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. Filing Code: FE-101. Producer or source: Carpenter.

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Essai d'application de modèles météorologiques au calcul du moment d'apparition de deux phases phénologiques | Application of Meteorological Models for the Calculation of the Beginning of Two Phenological Phases

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2000.0385 ◽

2000 ◽

Vol 151 (10) ◽

pp. 385-397

Author(s):

Bernard Primault

Keyword(s):

Sunshine Duration ◽

Fruit Trees ◽

Swiss Alps ◽

Winter Solstice ◽

Phenological Data ◽

Thermal Thresholds ◽

The Mean ◽

Two Parameters ◽

Meteorological Models ◽

Phenological Phases

Many years ago, a model was elaborated to calculate the«beginning of the vegetation's period», based on temperatures only (7 days with +5 °C temperature or more). The results were correlated with phenological data: the beginning of shoots with regard to spruce and larch. The results were not satisfying, therefore, the value of the two parameters of the first model were modified without changing the second one. The result, however, was again not satisfying. Research then focused on the influence of cumulated temperatures over thermal thresholds. Nevertheless, the results were still not satisfying. The blossoming of fruit trees is influenced by the mean temperature of a given period before the winter solstice. Based on this knowledge, the study evaluated whether forest trees could also be influenced by temperature or sunshine duration of a given period in the rear autumn. The investigation was carried through from the first of January on as well as from the date of snow melt of the following year. In agricultural meteorology, the temperature sums are often interrelated with the sunshine duration, precipitation or both. However,the results were disappointing. All these calculations were made for three stations situated between 570 and 1560 m above sea-level. This allowed to draw curves of variation of the two first parameters (number of days and temperature) separately for each species observed. It was finally possible to specify the thus determined curves with data of three other stations situated between the first ones. This allows to calculate the flushing of the two tree species, if direct phenological observation is lacking. This method, however, is only applicable for the northern part of the Swiss Alps.

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Control of an adiabatic continuous reactor by feeding catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802903 ◽

1980 ◽

Vol 45 (11) ◽

pp. 2903-2918 ◽

Cited By ~ 1

Author(s):

Josef Horák ◽

Zina Valášková ◽

František Jiráček

Keyword(s):

Steady State ◽

Reaction Temperature ◽

Continuous Reactor ◽

Control Element ◽

Inlet Temperature ◽

Switching Cycle ◽

Point Temperature ◽

Set Point ◽

Constant Rate ◽

Laboratory Reactor

Algorithms have been presented, analyzed and experimentally tested to stabilize the reaction temperature at constant inlet temperature and composition of the feed by controlled dispensing of the catalyst. The information for the control element is the course of the reaction temperature. If the temperature of the reaction mixture is below the set point, the catalyst is being fed into the reactor at a constant rate. If the reaction temperature is higher the catalyst dispenser is blocked; dispensing of the catalyst is not resumed until the set point temperature has been reached again. The amount of catalyst added is a function of the duration of the switching cycle. The effect has been discussed of the form of this function on the course of the switching cycle. The results have been tested experimentally on a laboratory reactor controlled in an unstable steady state.

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Batch Precipitation of Lead Iodide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19941301 ◽

1994 ◽

Vol 59 (6) ◽

pp. 1301-1304

Author(s):

Jaroslav Nývlt ◽

Stanislav Žáček

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Crystal Size ◽

Lead Nitrate ◽

Lead Iodide ◽

Constant Rate ◽

Mean Size ◽

The Mean

Lead iodide was precipitated by a procedure in which an aqueous solution of potassium iodide at a concentration of 0.03, 0.10 or 0.20 mol l-1 was stirred while an aqueous solution of lead nitrate at one-half concentration was added at a constant rate. The mean size of the PbI2 crystals was determined by evaluating the particle size distribution, which was measured sedimentometrically. The dependence of the mean crystal size on the duration of the experiment exhibited a minimum for any of the concentrations applied. The reason for this is discussed.

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