Trauma
 R.A.S HEMAT, MB;BCh, FRCSI, DUL.
The whole question about trauma is the protection-preservation of the human being during prolonged circulatory arrest (>1 hr), followed by resuscitation to survival without brain damage.
The host response to injury involves a complex set of interactions of different:
1- cytokines, 2- chemokines, 3- hormones, 4- neurotransmitters, 5- cell types, 6- organs.
During complete ischaemic anoxia, the level of energy (phosphocreatine, PCr and adenosine triphosphate, ATP) decreases to near zero in all tissues at different rates, depending on stores of oxygen and substrate, it is fastest in the brain (» 5 min), and slower in the heart and other vital organs.
During reperfusion and reoxygenation, lactate and molecular breakdown products can create osmotic edema and rupture of organelles and mitochondria.
During reperfusion and reoxygenation there is:
1-Osmotic edema and rupture of organelles and mitochondria.
2-Capillary leakage results in interstitial edema.
3-Superoxide may be formed from several sources: a- directly from AA metabolism by cyclooxygenase; b- by the XO system; c- via the electron transport chain; d- by activation of NADPH-oxidase in accumulated neutrophils in the microvasculature or after diapedesis into tissue.
Activation of nitric oxide synthase by Ca2+ lead to production of NO, which can combine with superoxide to generate peroxynitrite (ONOO-).
OFR induces the following
1-DNA injury and programmed cell death.
2-lipid peroxidation, leaking membrane and cell death.
3-Damage cellular lipids, protiens and nucleic acid.
Antioxidants, used before or during reperfusion, have been shown to efficiently prevent reoxygenation injury.
Debridement, has been used by the French for several centuries. it means "to relieve tension and establish drainage by incision". During the World War I, the word was adopted into English, but its meaning was confused in the transition.
Elevated intra-abdominal pressure may impair organs and physiologic function by producing an abdominal compartment syndrome (ACS).
Hypothermia occurs in as many as two thirds of severely injured patients and is associated with severe complication including atrial and ventricular arrhythmias, coma, coagulopathy, decreased cardiac performance, and death. The survival times and rates are increased by moderate hypothermia (31o C) or 100% oxygen inhalation. Hypothermia prolongs the ischaemic times of all tissues that is compatible with eventual survival following replantation from 6 to 24 hours.....etc.
May, 2001
Note: The information in this article has been excerpted from the following books: urotext-ebook simplifying urology, Principles of modern urology, by Dr. R.A.S HEMAT. Permission is granted to copy and redistribute this document electronically as long as it is unmodified. This article may not be sold in any medium, including electronic, CD-ROM, or database, or published in print, without the explicit, written permission of Dr. R. A. S. Hemat.
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Dr. R.A.S HEMAT declares no conflicts of interest or financial interests in any product or service mentioned in this article, including grants, employment, stock holdings, gifts, or honoraria.
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