Reviews
10.1177/1534734604265534 3 PANDEY and BURN RADIATION, RAJANWOUNDS
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Burn Injuries From Radiation Manoj Pandey,* MS, and Balakrishnan Rajan,† MD, Departments of *Surgical Oncology and †Radiotherapy, Regional Cancer Centre, Thiruvananthapuram, Kerala, India
Accidental exposure to radiation leading to injury and illness occurs notwithstanding safety devices and protocols used for protection. The medical management of radiation casualties is a major concern. Radiation effects are principally thermal, similar to electrical burn injuries, but with some unique systemic expression. The pathological effects of radiation to the skin are known; it is often difficult to assess the level of severity, quickly and with accuracy, because of the delay between exposure and the appearance of lesions and obscured le-
sions. The severity depends mainly on the nature of the radiation. High-energy penetrating radiation causes more irreversible damage than low-energy radiation, which penetrates tissues less than the former. A thorough knowledge, high index of suspicion, and a team approach are keys to successful management.
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treatment and research as tracers to study body systems, are also sources of radiation. As small doses are used and since patients are monitored very thoroughly, the risks of damage from such exposures are kept minimal. Nevertheless, problems occur. Radiation burns are often caused by accidental exposure to high-dose radiation or radioisotopes.
t is well known that radiation from manmade sources can cure as well as kill. For example, radiation-induced health damage in patients receiving radiotherapy leads to systemic and skin problems that manifest as burn wounds. Such damage also occurs on the lower extremities of the body. Accidental radiation exposures occur despite widespread education and training and safety measures of the highest quality. The First Consensus Development Conference on the Treatment of Radiation Injuries (Washington, DC, 1989), described the most appropriate treatment for the hematopoietic and infectious complications of radiation injuries and for combined radiation and traumatic/ burn injuries.1 This article presents an overview of the problems caused by radiation, excluding overexposure to sunlight. Such imaging devices as x-ray, fluoroscopy machines, and computerized tomography scanners are all potential sources of radiation. Radioisotopes, used for Correspondence should be sent to: Dr Manoj Pandey, Associate Professor, Surgical Oncology, Regional Cancer Centre, Medical College PO, Trivandrum 695011, Kerala, India;
[email protected].. Conflict of Interest: None. DOI: 10.1177/1534734604265534 © 2004 Sage Publications
LOWER EXTREMITY WOUNDS 3(2);2004 pp. 96–99
Key words: burns, injury, lower limb, photon, devices, radiation syndrome
SOURCES OF RADIATION Devices used to generate radiation include sealed sources used for industrial radiography, teletherapy, and accelerators. Sealed sources are used by industry for purposes of quality control, for example, to measure the thickness of sheets of paper or metal or the density of metals used in construction. Sealed sources are also used for security screening of baggage and by the travel industry. Other industrial uses of sealed sources include irradiation of food either for decontamination or to prolong shelf life. Teletherapy is the medical use of radiation. As the term indicates, treatment is delivered using a source that is kept away from the body; this process is also called external beam radiotherapy. It is based on the concept that tumors are more susceptible to radiation than the normal tissue. Such treatment may be delivered using Cobalt 60 as radiation source that produces
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gamma rays (average energy ~ 1.17 and 1.38 Me V). Cobalt sources are slowly being replaced by high-energy linear accelerators. Accelerators are used in industry, research, and medicine. Accelerators produce particles of different energy levels with specific uses as their penetration depths vary. Hence, the use of accelerators in oncology is increasing. Brachytherapy is treatment where the radiation source is placed within the body; Radium, Caesium, or Iridium may be used to target select organs within the body. Despite the widespread use of radiation for treatment, the occurrence of hazardous burns is limited; therefore, this article deals with the broader aspect of this problem. A recent search of the relevant Web sites revealed that 191 accidents with sealed sources, 71 with x-ray devices, 21 with accelerators, and 78 with radioisotopes had been reported.2 During the same period, by comparison, 18 critical accidents involving reactors, critical assemblies, and chemical operation were reported. Such critical events normally produce considerable heat as well as radiation, and their effects are generalized rather than localized on the person. Out of 115 victims of the Chernobyl breakdown, 56 persons had radiation burns, 17 had intestinal syndrome, 80 had oropharyngeal syndrome, and 7 had interstitial radiation pneumonitis.3 CLINICAL PRESENTATION The clinical presentation of a patient suffering radiation-induced illness is determined by the extent of exposure to radiation. The general effect of radiation is described as acute radiation syndrome (ARS). The factors that determine such a sickness are a large radiation dose (> 0.7 Gy), the radiation source must usually be external to the body, the radiation must penetrate the body, a significant proportion of the body should be exposed, and the dose must be delivered over a short period of time. The 3 classical ARS syndromes are hematopoietic or bone marrow syndrome, gastrointestinal syndrome, and cardio vascular/central nervous system syndrome.4 The well-known effects of excess radiation may be classified as thermal, similar to those resulting from electrical burn wounds, but with some unique systemic expressions. Systemic derangements as well as behavioral functions consequent to radiation overexposure have been understood from animal experiments.5 ARS has 4 stages. The stage of prodrome (N-V-D stage; stands for nausea, vomiting, and diarrhea) lasts
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from minutes to several days. In the latent stage, the patient looks and feels generally healthy, and this may last from several hours to a few weeks. This is followed by manifest illness stage where the patient develops specific symptoms, and finally the stage of recovery or death.4 The combined injury syndrome (CIS) is defined as mechanical and/or thermal trauma associated with radiation injury. Each of these injuries is characterized by several systemic reactions, especially the immune system and the fluid balance in man. The pathogenic mechanisms of CIS are not well understood. There is a growing body of evidence that implicates 2 different effects to compromise organ function: (i) similar or identical reactions of each trauma type resulting in increased systemic damage and (ii) posttraumatic alterations, where the effect of a type of trauma synergistically increases the totally different effect of the other.6 Burn wounds confined to the lower extremities often present as cutaneous radiation syndromes (CRS). The concept of CRS was introduced in recent years to describe pathological syndromes resulting from acute radiation exposure to skin. CRS can occur alone or as part of ARS. This is especially so with acute exposure to beta radiation or x-rays, or radioactive material falling on the person or patients or on the protected/ unprotected parts of those handling the radiation material.4 When the basal layer of skin is damaged by radiation, inflammation erythema and dry or moist desquamation occur. Damage to hair follicles may cause epilation within a few hours after irradiation; a transient and inconsistent erythema associated with itching also occurs. This may be followed by a latent phase that may last from a few days to weeks when intense reddening, blistering, and ulceration is visible. Healing mostly occurs spontaneously by regeneration; however, with very large doses, permanent hair loss, damage to sebaceous and sweat glands, atrophy, fibrosis, decreased or increased skin pigmentation, and ulceration or necrosis of the exposed tissue can occur. The pathological effects of radiation to the skin are well known and are described above. It is often difficult to assess quickly and with accuracy the level of severity because of the delay between exposure and appearance of the lesions and because of the hidden lesions in underlying tissues. The severity depends mainly on the nature of the radiation, high-energy penetrating radiation causing much more irreversible damage than low-energy lightly penetrating radiation. Pain is the first difficult problem to solve. It starts quickly, is con-
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stant at all stages, and rapidly dominates the clinical picture.7 MANAGEMENT OF RADIATION BURNS In cases of nuclear accidents, a number of victims should be expected to arrive in casualty about the same time. Hence the first thing to do is a complete clinical examination of each individual, followed by triage. It is advised to use radiation protection clothing for medical and paramedical staff. It is also advised to remove and dispose of clothing contaminated by radiation in recommended ways. If radiation exposure is suspected, the patients’ airway, breathing, and circulation (ABC) need to be secured; blood pressure should be monitored; and blood samples should be collected for routine hematology and biochemical analyses, electrolytes, HLA, and measurements of blood gases. Urine output should also be measured. When associated with major trauma, thermal burns, or respiratory injury, these are attended to first. Contamination is treated as needed, and lymphocyte counts need be monitored periodically. Diagnosis of radiation syndrome is difficult, as it causes no unique disease. Also, depending on the dose of radiation, the prodrome may not occur for hours or days or the patient may be in a latent stage and not exhibit symptoms. The dose of the exposure needs to be calculated to facilitate triage.8 At present, biological markers cannot be used to estimate the heterogeneity of the dose distribution. An alternative is to map the absorbed dose in the different regions of the body. Using a Monte Carlo calculation code, it is possible to simulate the accident while taking into account the specific morphology of the irradiated individual and his or her environment, as well as the source characteristics.9 If a patient has nausea, vomiting, and diarrhea, this should be treated symptomatically. All through this period, careful attention should be paid to whole blood counts. The whole body should be examined under good light conditions to record the areas of erythema, and photographic records should be maintained of areas of suspected damage. These steps follow other management that is similar to that used to care for thermal burns starting with supportive care in a clean environment. Broad-spectrum antibiotics and antiviral and antifungal agents should be started to prevent or treat infections. If lymphocyte counts begin to drop, bone marrow is supported using blood, blood products, and hematopoiesis agents. Psychological support should also be provided to the patients as needed.
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Local Management of Burns Radiation burns are managed as deemed necessary by the severity of the damage. First-degree burns usually do not require any treatment and heal spontaneously within 3 to 6 days. Topical calamine lotion may be applied to reduce itching. For the second- and thirddegree burns, the wound is cleaned with surgical detergent, all loose nonviable skin is removed, and hairs are shaved off. The initial cleaning is best achieved in a shower room with a handheld shower. Topical silver sulphadizine is applied liberally over the wound surface. The topical agent is selected to meet specific individuals’ needs. Other agents that may be used are 0.5% silver nitrate and Mafenide acetate. Other topical formulations can also be used in specific conditions.10 Surgical Management The most important role of surgery is wound cleaning and debridement. Most first- and second-degree burns would heal spontaneously by simple debridement and dressing. The patients with third-degree burns may require repeat excisions to prepare the wound for further surgical management. If partial thickness grafting is proposed, the objective is to generate a wound bed with healthy granulation. The recipient area should be free of radiation at the time of grafting. Artificially grown skin may also be used in these circumstances. Wound Closure The ultimate goal of radiation burn wound care is timely definitive closure of the wound. This can be achieved by thin or thick partial thickness skin grafts taken from elsewhere. Mesh grafts can be utilized to increase the extent of wound covered by skin from the donor site. Artificial skin may be used where available. Escharotomy and Fasciotomy Escharotomy is performed as “a ward procedure” to incise the eschar. The eschar covering a limb circumferentially is divided either mid-lateral or midmedial line. Anesthesia is not usually required. Bleeding is controlled using pressure dressings. This procedure is similar to that used to treat a thermal burn. Similarly, fasciotomy is required if the tissue pressure exceeds venous pressure at a point by causing
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limb edema. This usually follows an escharotomy when it fails. Pedicle or Free Flaps Pedicle or free flaps are required for patients with failed skin grafts, for those where the vascularity of the recipient area is low, or where radioactivity persists. It is important to remember that in cases of radioisotope burns the decay time of the relevant isotope determines the rate of radioactive decay. Pedicle or free flaps are usually required in patients with third-degree burns. Flap closure may also be used in patients with burns at sites that expose the major vessels and there is a chance of blowout, for example, in inguinal areas. Similarly, patients with burns at pressure points and weight-bearing areas of the lower limb also need flap closure. Timing of Surgery Initial surgical procedures must be completed during the short time period of 48-72 hours before onset of radiation-induced neutropenia and thrombocytopenia. This includes primary wound closure; management of all the abdominal, thoracical, and vascular injuries; and definite osteosynthesis. Later, all invasive procedures must be avoided due to the high risk of opportunistic infections and possible massive hemorrhage. When hematopoietic recovery begins, subsequent steps of surgical treatment can be taken into consideration. However, it is important that, as in conventional trauma, resuscitation and emergency care have priority and be performed independent of the degree of radiation injury.6 CONCLUSIONS The aim of this article was to present an overview of problems associated with radiation injuries of which
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burns are a specific case. Although considered rare in the past, radiation injuries are slowly becoming less so due to the increased use of radiation devices and nuclear power generation. The key to effective management is early diagnosis, detailed evaluation, and appropriate management. A team of experts including a surgeon, radiation biologist, radiation physicist, oncologist, and internist should ideally manage these patients. All such cases of radiation burns need to be reported to local radiation protection agencies. REFERENCES 1. Browne D, Weiss JF, MacVittie TJ, Pillai MV. Protocol for the treatment of radiation injuries. Adv Space Res 1992;12(2-3):165-8. 2. Summary of radiation accidents since 1944. URL: http://www. meddean.luc.edu/lumen/MedEd/radiation/radaccid.html. Accessed November 19, 2003. 3. Gus’kova AK, Baranov AE, Barabanova AV, Moiseev AA, Piatkin EK. The diagnosis, clinical picture and treatment of acute radiation sickness in the victims of the Chernobyl atomic electric power station: II. Non-bone marrow syndromes of radiation lesions and their treatment. Ter Arkh 1989;61(8):99-103. 4. Centers for Disease Control and Prevention. Acute radiation syndrome, fact sheet for physicians. Atlanta, GA: Author; 2003. 5. Ciano M, Burlin JR, Pardoe R, Mills RL, Hentz VR. High-frequency electromagnetic radiation injury to the upper extremity: local and systemic effects. Ann Plast Surg 1981;7(2):128-35. 6. Engelhardt M, Kaffenberger W, Abend M, Gerngross H, Willy C. Radiation and burn trauma (combined injury) considerations in surgical treatment. Unfallchirurg 2001;104(4):333-42. 7. Nenot JC. Medical and surgical management for localised radiation injuries. Int J Radiat Biol 1990;57(4):783-95. 8. Ricks RC, ed. The medical basis for radiation accidents preparedness. The clinical case of victims. New York: Parthenon; 2002. 9. Bottollier-Depois JF, Gaillard-Lecanu E, Roux A, et al. New approach for dose reconstruction: application to one case of localized irradiation with radiological burns. Health Physiol 2000;79(3):251-6. 10. Pruitt BA Jr, Goodwin CW Jr, Pruitt SK. Burns. Including cold, chemical and electric injuries. In Sabiston DC Jr, ed. Textbook of surgery. The biological basis of modern surgical practice (14th ed.). Philadelphia: W. B. Saunders; 1991.
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