Heat Exchange Through Cutaneous Vasodilation After Atropine Treatment in Two Environments

Heat Exchange Through Cutaneous Vasodilation After Atropine Treatment in Two Environments
Author:
Publisher:
Total Pages: 35
Release: 1987
Genre:
ISBN:

This report summarizes two tightly controlled laboratory studies in which the thermo-regulatory effects of an intramuscular injection of atropine sulfate (2 mg) were compared with a placebo injection of sterile saline during two environmental conditions. Four subjects were tested in each environmental condition (22 C or 30 C) during seated cycle exercise at a moderate exercise intensity (55% VO2 peak). Esophageal temperature (T), mean weighted skin temperature (Tsk), and forearm sweating rate (ms) were continuously measured during 30 minutes of rest and 35 minutes of exercise. Skin blood flow (FBF) from the forearm was measured twice each minute by venous occlusion plethysmography. The expected decrease in whole body and local sweating rate ( -60%) occurred in both environments in the atropine treated subjects. The increased skin blood flow compensated for the suppression in sweating increasing dry heat loss in the atropine experiments. The atropine-induced vasodilation was widespread as skin temperatures increased at all sites measured. These results suggest that the peripheral modification of cutaneous blood flow which occurs in atropine treated subjects is sufficient to alter heat exchange in both warm and cool environments.

Heat Exchange Through Cutaneous Vasolidation After Atropine Treatment in a Cool Environment

Heat Exchange Through Cutaneous Vasolidation After Atropine Treatment in a Cool Environment
Author: Margaret A. Kolka
Publisher:
Total Pages: 21
Release: 1987
Genre:
ISBN:

This report summarizes a tightly controlled laboratory study in which the thermoregulatory effects of an intramuscular injection of atropine sulfate were compared with a placebo injection of sterile saline during exposure to a cool environment. Four subjects were tested during seated cycle exercise at a moderate exercise intensity. The expected decrease in whole body and local sweating rate occurred in the atropine treated subjects. By 10-15 min of exercise, radiative and convective heat exchange was significantly elevated from the head, chest, back, arm, forearm and thigh in the atropine experiments. Core temperature actually decreased 0.2 C in the atropine treated subjects during exercise as a result of enhanced dry heat exchange. By 25 min of exercise, Skin blood flow (FBF) was 98% greater after atropine treatment. These results show that the peripheral modification of cutaneous blood flow which occurs in atropine treated subjects is sufficient to markedly alter heat exchange in a cool environment. Keywords: Anticholinergic, Dry heat exchange, Sweating, Thermoregulation, Vasodilation.

Aerospace Medicine and Biology

Aerospace Medicine and Biology
Author:
Publisher:
Total Pages: 184
Release: 1990
Genre: Aviation medicine
ISBN:

A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).

Medical Infrared Imaging

Medical Infrared Imaging
Author: Mary Diakides
Publisher: CRC Press
Total Pages: 641
Release: 2012-12-12
Genre: Medical
ISBN: 143987249X

The evolution of technological advances in infrared sensor technology, image processing, "smart" algorithms, knowledge-based databases, and their overall system integration has resulted in new methods of research and use in medical infrared imaging. The development of infrared cameras with focal plane arrays no longer requiring cooling, added a new dimension to this modality. Medical Infrared Imaging: Principles and Practices covers new ideas, concepts, and technologies along with historical background and clinical applications. The book begins by exploring worldwide advances in the medical applications of thermal imaging systems. It covers technology and hardware including detectors, detector materials, un-cooled focal plane arrays, high performance systems, camera characterization, electronics for on-chip image processing, optics, and cost-reduction designs. It then discusses the physiological basis of the thermal signature and its interpretation in a medical setting. The book also covers novel and emerging techniques, the complexities and importance of protocols for effective and reproducible results, storage and retrieval of thermal images, and ethical obligations. Of interest to both the medical and biomedical engineering communities, the book explores many opportunities for developing and conducting multidisciplinary research in many areas of medical infrared imaging. These range from clinical quantification to intelligent image processing for enhancement of the interpretation of images, and for further development of user-friendly high-resolution thermal cameras. These would enable the wide use of infrared imaging as a viable, noninvasive, low-cost, first-line detection modality.