CRUSH INJURY, COMPARTMENT SYNDROME, AND OTHER ACUTE TRAUMATIC ISCHEMIAS
Crush injuries occur when body tissues are severely traumatized such as in motor vehicle accidents, falls, and gunshot wounds. These injuries frequently occur in the extremities. When crush injuries are severe, the rate of complications such as infection, non-healing of fractures and amputations range up to 50%.
Release of pressure that occluded circulation continues the sequence of edema, anoxia and tissue destruction. Post traumatic edema further reduces oxygen supply to tissues by increasing the oxygen distance must travel to diffuse to and from cells, and by directly impairing microcirculation. The resulting decrease in tissue oxygen tension impairs wound healing by interfering with ability of neutrophils to fight bacteria, new cell growth, collagen disposition.
Tissue oxygen tension below 33mmHg will increase infection risk and decreases healing. White blood cells need oxygen to kill microbes. New cell and vessel growth cannot take place without oxygen-dependent collagen, so that a wound does not occur.
Benefits of Hyperbaric Oxygen Therapy
When used as an adjunct to orthopedic surgery and antibiotics, hyperbaric oxygen (HBO2) therapy shows promise as a way to decrease complications from severe crush injuries. HBO2 increases oxygen delivery to the injured tissues, reduces swelling and provides an improved environment for healing and fighting infection. HBO reduces reperfusion injury by preventing lipid peroxidation, neutrophil adherence, and free radical buildup.
Increased oxygen tensions in hypoxic tissues allow healing and help prevent spread of infection and damage to adjacent, non-involved tissue, decreasing complication rates and cost of management.
Hyperbaric Oxygen Therapy at 2 ATA increases blood oxygen content by 25%, but increases plasma and tissue oxygen tension 10 to 30 fold. The net effect is a threefold increase in oxygen diffusion through tissue fluids.
Increased oxygen reduces edema through vasoconstriction, which further promotes oxygenation. Increased oxygen tensions in hypoxic tissues allow healing and helps prevent spread of infection and damage to adjacent, non-involved tissue, decreasing complication rates and cost of management.
Hyperbaric Oxygen Therapy speeds demarcation of non-viable tissue, and reduces reperfusion injury by preventing lipid peroxidation, neutrophill adherence, and free radical buildup.
A placebo-controlled randomized and double blind clinical trial in acute limb-threatening trauma to the extremities. Statistically significant improvement in outcome occurred in the HBO group. HBO therapy improved wound healing, reduced the number of surgical procedures, and likewise reduced the number of amputations that became necessary. (Bouachour MD, Cronier P, Gouello JP, et al.:The Journal of Trauma: Injury, Infection, and Critical Care 1996; 41(2): 333-339)
Notable Case studies
Bouachour MD, Cronier P, Gouello JP, ET AL.: Hyperbaric oxygen therapy in the management of crush injuries: A randomized double-blind placebo-controlled clinical trial. The Journal of Trauma: Injury, Infection, and Critical Care 1996; 41 (2): 333-339. A Placebo-controlled randomized and blinded clinical trial in acute limb-threatening trauma to the extremities. Statistically significant improvement in outcome occurred in the HBO group. HBO therapy improved wound healing, reduced the number of surgical procedures, and likewise reduced the number of amputations that became necessary.
Nylander G. Lewis D. Nordstrom H, ET AL.: Reduction of post ischemic edema with hyperbaric oxygen. Plastic and reconstructive surgery 1985; 76 (4): 596-601The consistent laboratory finding of improved outcomes following acute peripheral ischemia and treatment with HBO.
Thom SR, Mendiguren I, Hardy K, ET AL.: Inhabitation of human neutrophil B2-integrin-dependent adherence by hyperbaric O2. AM J Physiol 1997; 272 (Cell Physiol. 41): C 770-C777This paper is included here to demonstrate the depth at which researchers have investigated in order to elucidate HBO’s therapeutic effects in ischemia-reperfusion injury.
Strauss MB, Hargens AR, Gershuni DH, ET AL.: Reduction of skeletal muscle necrosis using intermittent hyperbaric oxygen in a model compartment syndrome. The Journal of Bone and Joint Surgery 1983; 65-A: 656-662Further basic science to support the clinical application of HBO therapy in acute peripheral ischemias: compelling histological evidence of benefit.
Radonic V, Baric D, Giunio L, ET AL.: War injuries of the femoral artery and vein: A report on 67 cases. Cardiovascular Surgery 1998; 5 (6): 641-647A clinical series of war wounded patients. “Hyperbaric oxygen therapy should be used in selected cases in order to improve tissue oxygenation, wound healing host defense mechanisms and therapy.”
Acute traumatic ischemia occurs when an injury interrupts blood flow to an extremity. Examples are open fractures that tear major arteries or crush injuries and skeletal muscle compartment syndromes that starve the microcirculation. This can lead to infection, nonhealing wounds, united fractures, and necrosis, which may require amputation. Problems are compounded in compromised patients such as those with diabetes, malnutrition, advanced peripheral vascular disease, or collagen vascular diseases.
Signs of it are pain, edema, anuria (stopped urine formation) pallor and no distal pulses.