A comparison of epinephrine only, arginine vasopressin only, and epinephrine followed by arginine vasopressin on the survival rate in a rat model of anaphylactic shock
ABSTRACT Epinephrine and more recently arginine vasopressin (AVP) alone or in combination have been proposed in patients with anaphylactic shock, but few experimental data exist. The authors investigated the effects of epinephrine only, AVP only, or epinephrine followed by AVP in a model of anaphylactic shock.
Ovalbumin-sensitized Brown Norway rats were anesthetized, intubated, and shock induced with ovalbumin. Rats (n = 6/group) were randomly allocated to receive 5 min after shock onset: (1) saline (no-treatment group); (2) two boluses of epinephrine followed by continuous infusion (epinephrine group); (3) AVP bolus followed by continuous infusion (AVP group); (4) epinephrine bolus followed by AVP continuous infusion (epinephrine + AVP group). Mean arterial pressure (MAP) and skeletal muscle oxygen pressure (PtiO2) were measured. Continuous infusion rates were titrated to reach MAP values of 60 mmHg. Survival was analyzed.
Without treatment, MAP and PtiO2 decreased rapidly with 0% survival. In the epinephrine group, MAP and PtiO2 recovered after an initial decrease, with 84% survival. In the AVP group, MAP was partially restored and subsequently decreased; PtiO2 values decreased to values similar to those in the no-treatment group; survival was 0%. In the epinephrine + AVP group, MAP and PtiO2 values increased more slowly as compared with the epinephrine group; survival was 100%.
In this model of anaphylactic shock, early treatment with epinephrine followed by continuous epinephrine or vasopressin infusion resulted in an excellent survival rate, whereas vasopressin only resulted in a 100% death rate. These experimental results suggest that epinephrine must still be considered as the first-line drug to treat anaphylactic shock.
- SourceAvailable from: Lesley M Foley
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- "MAP was statistically significant albeit modestly decreased compared to baseline starting 15 min after ROSC in all three groups (Table 2). We assessed the response of CBF to increasing MAP in a separate group of animals undergoing 12 min asphyxia by measuring CBF 60 min after ROSC, before and after increasing MAP to baseline values via iv epinephrine infusion (dose range 5-30 μg/kg/min) (Dewachter et al. 2007). Figure 4 illustrates CBF before and after correction of MAP to baseline values in each of the four animals studied. "
ABSTRACT: Cerebral blood flow (CBF) alterations after asphyxial cardiac arrest (CA) are not defined in developmental animal models or humans. We characterized regional and temporal changes in CBF from 5 to 150 mins after asphyxial CA of increasing duration (8.5, 9, 12 min) in postnatal day (PND) 17 rats using the noninvasive method of arterial spin-labeled magnetic resonance imaging (ASL-MRI). We also assessed blood-brain barrier (BBB) permeability, and evaluated the relationship between CBF and mean arterial pressure after resuscitation. After all durations of asphyxia CBF alterations were region dependent. After 8.5- and 9-min asphyxia, intense subcortical hyperemia at 5 min was followed by return of CBF to baseline values by 10 mins. After 12-min asphyxia, hyperemia was absent and hypoperfusion reached a nadir of 38% to 65% of baselines with the lowest values in the cortex. BBB was impermeable to gadoteridol 150 mins after CA. CBF in the 12-min CA group was blood pressure passive at 60 min assessed via infusion of epinephrine. ASL-MRI assessment of CBF after asphyxial CA in PND 17 rats reveals marked duration and region-specific reperfusion patterns and identifies possible new therapeutic targets.Journal of cerebral blood flow and metabolism: official journal of the International Society of Cerebral Blood Flow and Metabolism 11/2008; 29(1):197-205. DOI:10.1038/jcbfm.2008.112 · 5.34 Impact Factor
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ABSTRACT: A mathematical formulation of the organization level of an intelligent machine, modeled as a Knowledge Based (Expert) System is derived and analyzed. Characteristic functions of the organization level of such a machine are: machine reasoning, machine planning, decision making, feedback (learning) and memory exchange. Probabilistic models are used to express analytically their individual functions. Information Theory measures and concepts are utilized to describe quantitatively the flow of knowledge in that level as the machine operates. An example illustrates this approach.Robotics and Automation. Proceedings. 1986 IEEE International Conference on; 05/1986
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ABSTRACT: The integration of RF n-and p-LDMOS transistors into a CMOS or BiCMOS platform allows the use of complementary circuit techniques and enables efficient solutions for linear RF power amplifiers, power switches, DC/DC converters and high voltage IO circuits. We demonstrate the modular integration of high performance n-LDMOS devices and a record p-LDMOS transistor into a low-cost 0.25 μm SiGe:C RF-BiCMOS technology. In addition to n-LDMOS transistors on a p-substrate with breakdown voltages near 30 V, isolated n-LDMOS- and p-LDMOS transistors can be manufactured on the same wafer and achieve breakdown voltages of 11.5 V and 13.5 V and f<sub>T</sub>/f<sub>max</sub> values of 23/48 GHz or 13/30 GHz, respectively.Solid-State Device Research conference, 2004. ESSDERC 2004. Proceeding of the 34th European; 10/2004