Intensive Care M e d i c i n e

Intensive Care Med. 7, 71-76 (1981)

9 Springer-Verlag 1981

Primary Excision and Immediate Wound Closure W. C. Quinby, Jr., J. F. Burke, and C. C. Bondoc Harvard Medical School, Massachusetts General Hospital, Shriners Burns Institute, Boston, Massachusetts, USA

Abstract. Surgical principles of early excision of devitalized tissue and prompt wound closure which govern the management of all traumatic injuries have been developed in the primary treatment of burns. Topical and systemic antibiotics which delay wound infection and control invasive sepsis provide an initial period of two to three weeks in which wound excision and closure is safe and effective. Full support of the central and peripheral circulation, respiratory function, nutrition, and musculoskeletal function are essential features of care until the burn wound is eliminated and closed. Following initial evaluation, wound excision is carried beyond the deepest level of injured tissue. Excision to the level of muscle fascia is used for fullthickness injury and sequential excision in or below the dermis for deep dermal injury. Techniques of skin grafting and subsequent care of the graft are described, including the use of human allografts. Primary excision has reduced mortality, morbidity and later reconstructive measures by a factor of 50% when compared to results obtained by awaiting spontaneous separation of eschar with later grafting. With massive burns the use of allografts from familial donors of close immunologic type and immunosuppression of the patient prolong the period before allograft rejection and permit repeated harvest of the patient's donor sites for permanent wound closure. Over 60% of young burn victims with greater than 70% full-thickness burn injury have survived with this method of treatment. Key words: Primary excision - Wound closure Burns Primary Excision and Immediate Wound Closure

It is nearly one hundred years since anti-sepsis came to dominate the treatment of burns. All that is has accomplishedso far as we

can see from the data available, is to offset the good that sound physiological and surgical principles and modern anti-septic technique should have afforded. Carl Moyer, M. D. Ann Surg 137:628 (1953)

I. Development Within fifteen years of the above writing, topical agents such as 0.5% AgNO 3 solution [14], 10% sulfamylon ointment [13], and 1% silversulfadiazine ointment [2] were shown to provide significant suppression of burn wound sepsis, while new systemic antibiotics effective against gram positive and gram negative organisms demonstrated improved control of invasive infection originating in the wound. These advances have remarkably improved the results of burn therapy; particularly so the topical agents which have limited the deepening of shallow partialthickness burns by infection and thus permitted their spontaneous healing. But neither topical nor systemic antibiotics have prevented the ultimate metabolic and septic effects of a large, unhealed, full-thickness burn wound which of itself continues to endanger life and to be the source of major organ dysfunction until it is permanently closed. Anti-bacterial agents, therefore, have improved the healing of shallow burns and have prolonged the interval between burn injury and wound colonization in deep burns, but have not changed the thrust of Dr. Moyer's statement. A review of the older literature on excisional treatment of burns [8, 10, 18] shows that the efforts to apply the same "sound physiological and surgical principles" of excision of devitalized tissue and wound closure so well established for other traumatic wounds were often thwarted by factors of progressive infection caused by delay, of varying depth or great extent of specific burn wounds, and of failure to 0342-4642/81/0007/0071/$01.20

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develop and apply appropriate techniques, Early and total excisions of circumscribed full-thickness burns of limited size were highly successful [16], but, since most burns are a mosaic of varying depths, an excision limited to the declared full-thickness portions often failed because unexcised surrounding shallower areas became contaminated, and infection spread with destructive effects to the adjacent parts that had been excised and grafted. It became clear that as long as significant devitalized tissue remained in the wound, control of infection, good metabolic balance, or successful grafting could not be realized. These experiences led to the conviction that all deep dermal portions of the wound as well as the full-thickness ones should be removed and to the development of the technique of sequential excision of deep partialthickness areas, leaving unexcised only such shallow portions as would heal within two to three weeks under topical therapy. Mortality rates of burn injury have long been equated with the square area of body surface burn. In practice, mortality is more acccurately related to the third dimension of burn depth. Despite major advances in respiratory support, in parenteral and intravenous supplemental nutrition, and in the availability of blood and blood components, the metabolic responses and nutritional losses caused by an open wound of more than 25~ of the body surface are often lethal. The incidence of organ failure, of graft failure, and of the development of toxemia or invasive infection increases sharply with the time during which a large wound remains open and with age or concomitant disease of the patient. As time passes, each operative manipulation of the wound may disseminate more bacteria, and the tolerance for anesthesia and blood loss sharply decreases. To reduce such hazards excisional therapy must be done early. All of the deep dermal and full-thickness burn must be removed within the first two weeks from injury. The resulting wounds must be closed primarily, since even after the eschar is completely excised, the wound becomes infected unless it is closed promptly. With major burn two problems predominate. First, the impact of excisions must not be overwhelming to the patient's natural defenses. Here experience indicates that the combined areas of excision and graft donor site should not exceed 35~ BSA, which implies that the excised area should not exceed 1 5 - 2 0 % BSA at a single operation. Second, with very extensive burns there may be insufficient unburned skin from which to obtain grafts in order to close the wound. This deficiency can be overcome by the substitution of allografts whose integrity lasts about two weeks before rejection. With rejection, an

open unresolved wound again appears. Fortunately, donor sites heal sufficiently to be re-harvested for autografts in about two weeks. Therefore, allografts can be removed before rejection, and the wound closed with permanent autografts from a second harvest. The ultimate disabilities from scar, contracture, stiffened joints, and inflexible grafted areas are directly related to the amount of chronic granulation tissue and the duration of the inflammatory state of the wound. The results of primary excision and grafting of deep burns of small or moderate size dramatically illustrate improved functional and cosmetic outcome when compared to the practice of waiting for eschar to separate and granulation to develop before closing the wound with a graft [6]. The benefits of the excisional method with major burns is shown in terms of reduced mortality and morbidity as compared to other plans of treatment. When pressed to the extreme test of massive burns (more than 70~ body surface area full-thickness injury), the use of closely-matched donors for allografts [1], immunosuppression of the patient with antithymocyte globulin to delay allograft rejection [17], skin banking techniques [3], hypotensive anesthesia to reduce operative blood loss [15], and control of the environment surrounding the patient to minimize bacterial contamination [7] have been successful in a high percentage of young patients.

1I. Supportive and Preventive Measures

It is essential that the plan of primary excision be carried out with the scrupulous control and support of the patient's organ functions common to all trauma surgery. If the burn injury is severe or has an inhalation component, a host of monitoring techniques, support systems, and corrective or preventive measures may be required. Their complexity is beyond the scope of this article, but in general, supportive treatment aims to maintain normal values and to apply preventive measures where need for them is anticipated.

a) Circulatory. Cardiac output may be diminished for a few days after major burns, followed by markedly increased values. It is not established whether a "depressant factor" is elaborated from burned tissue or whether it is specific for cardiac function. Diminished cardiac output is not a contraindication to wound excision, and there is clinical evidence that removal of large areas of full-thickness eschar may be beneficial to myocardial function.

W. C. Quinby,Jr. et al.: PrimaryExcisionand ImmediateWoundClosure Good tissue perfusion must be maintained. Escharotomy of constricting deep burns of extremities may be required to ensure adequate circulation. Early resuscitation fluids which do not include colloid solutions result in a dilution of serum protein and excessive edema which interfere with the conduct of anesthesia. Both red cells and colloid are often required to maintain normal circulation before and during primary excision. Fresh frozen plasma is superior to albumin solutions because it contains necessary coagulation factors. Since blood platelets may be sequestered in an extensive burn wound, platelet transfusion may be required for excessive bleeding during operation if values are below 30,000/ml 3. The use of tourniquets on extremities reduces blood loss. If the technique is familiar, hypotensive anesthesia may be valuable [15]. However, with heavily colonized wounds, these techniques are contraindicated since reduced tissue perfusion of even short duration favors bacterial growth in the wound.

b) Respiratory. The diagnosis of inhalation injury is made by history, examination, endoscopy, and monitoring of blood gas values. Escharotomy of restricting thoracic burns improves compliance, abdominal distention must be prevented by nasogastric suction, and tracheal intubation is best done promptly before laryngeal or head and neck edema form. Both early and late in the course of a burn the effects of hypoxia are often reflected in failure of grafts and unfavorable progress of sepsis. In the event of pulmonary injury, nasotracheal intubation is preferable to tracheostomy, and maximal respiratory support is required. c) Anti-Bacterial Measures. In practice, daily swab cultures are as reliable as quantitative wound cultures obtained by biopsy. In most hospitals standard isolation techniques are used, while in others, special laminar flow nursing units constructed about the bed provide significant protection against environmental bacteria and cross-infection or auto-infection [4]. Although a rinsing shower or needle spray may be acceptable to wash topical ointments from a wound, it appears inevitable that immersion or "tubbing" of the patient promptly contaminates the entire wound with fecal flora and is incompatible with the program of early excision. Thick gauze dressings saturated with 0.5% silver nitrate are versatile in providing simultaneous protection of grafted burns, surrounding areas of shallow burn, and adjacent donor sites against surface infection. This versatility is lost with ointments, but silversulfadiazine and sulfamylon

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penetrate burn eschar, whereas 0.5% AgNO 3 does not. Hence, the sulfonamides are advocated preoperatively to reduce the bacteria in eschar or wounds that are heavily colonized. Systemic antibiotics specific for invading organisms are used in circumstances of pneumonitis, urinary infection or toxemia and septicemia from wound organisms. Septic eschar or necrotic tissue are debrided gently and under the protection of antibiotics specific for the organisms. Preventive antibiotics effective against both gram positive and gram negative bacteria are used for 12 h before and 24-36 h after all wound excisions or manipulations. When their use is confined to such short periods, resistent strains, superinfection or opportunistic infections rarely occur.

d) Nutrition. Every means is used to minimize the impact of the metabolic losses which accompany major burn injury. Environmental temperature and humidity may be controlled to reduce the energy consumed in evaporative water loss or shivering if environmental nursing units are available. Throughout the course of the burn periods of ileus are managed by gastric suction, and progressive oral or gastric tube feedings of elemental or special diets are the predominant source of calories. Stress ulcer rarely occurs if antacids are used constantly. The excessive caloric demands and periods of intestinal dysfunction produced by wound or metabolic losses may necessitate intravenous hyperalimentation if the acute phase of the illness exceeds two weeks. The hazards of placement and care of central intravenous catheters must be accepted and minimized by scrupulous attention to protocol until good intestinal function returns and open wounds of less than 10- 15~ BSA remain. e) Function. The prolonged nature of the burn illness and requirements for immobilization of extremities to favor successful grafting cause stiffening of joints, loss of muscle mass and scar contracture. Active physiotherapy, splints to maintain positions of function, and getting the patient out of bed should not be delayed unduly. The program begins in the acute phase of burn injury and continues after healing is complete.

III. Technical Considerations

a) Evaluation o f the Wound. During a period of about 48 h from injury, increasing tissue pressure from wound edema and leaking of damaged

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capillaries causes progressive cellular ischemia and deepening of the initial burn injury. If the patient is hypotensive or hypoxic, or if circumferential deep burns of extremities limit tissue perfusion, evaluation of depth and extent is deceiving until shock is corrected and complete escharotomy of constricting eschar is done. After the edema and reabsorption phases, the two extremes of burn depth are not difficult to evaluate. Erythema which blanches on pressure, pain, hypersensitivity, and slight blistering characterize the superficial wound. By contrast, dense, inflexible, intensitive, avascular full-thickness injury may be white in color or various shades of brown to black indicative of coagulated protein. Between the two extremes, deep blistering, scarlet areas which do not blanch, and varying degrees of sensitivity to pinprick are manifest as partial-thickness wounds. Evaluations Of sensation, consistency, and capillary flow must be made repeatedly.

b) Primary Wound Care. Although the heat of severe burns destroys most of the surface bacteria, contamination is common at the scene of injury or in transport to the hospital. Wounds are totally cleansed with a neutral soap and saline solution together with mechanical removal of ruptured blisters and other foreign material. Following this, an appropriate topical agent should be applied. c) Topical Agents.

Continuously saturated wet dressings of 0.5% silver nitrate solution protect the wound against contamination and permit evaluation of its progress with each change of dressing. Although very superficial and very deep burn injury are easily recognized, the intermediate depths of dermal injury are more difficult to determine when silver sulfadiazine and sulfamylon ointments are used.

d) Wound Excision. Two types of surgical excision are applicable [5]. Burns of full-thickness depth are excised at the level of the deep fasciae and include the fascia or underlying muscle if they are found to be injured. In order to minimize blood loss, the operation is best carried out by the use of an electrosurgical knife with hemostatic cautery control of deep perforating vessels which supply the fat and skin [11]. Following excision, the peripheral normal skin retracts, bleeding from subdermal blood vessels is troublesome, and the edges of the wound present a perpendicular border between the surface of normal skin and the fascia. In order to immobilize the wound borders, to avoid the perpendicular edge, and to control bleeding, the edge of normal skin is sutured down to the fascia with running and interrupted sutures of catgut.

e) Sequential or Tangential Exc&ion. Moderate to deep dermal burns, or those where the depth extends to the fat in limited areas, are excised using a WatsonEdwards knife with a guard on the blade set at an appropriate depth. Slices of the burn tissue are excised sequentially until normal color and multiple bleeding vessels appear in the deep dermis or the subcutaneous fat, making certain that excision extends beyond the depth of any thrombosed veins. Sequential excision in this fashion causes a significant blood loss. Therefore, the area to be excised is divided into convenient segments in which excision and complete hemostasis with the electric cautery are completed before proceeding to an adjacent area. With burns of the extremities, elevation and the use of tourniquets further reduce bleeding. It is helpful to control any major Needing first and then to apply gauze sponges soaked in a solution of thrombin with circumferential pressure dressing for ten minutes before coagulating the remaining bleeding points. A careful review of wounds excised under tourniquet is required after the circulation is reestablished. In any form of excision it is essential that bleeding be totally controlled if successful grafting is to follow.

f)

Wound Closure. Small, circumscribed, fullthickness burns may be excised and closed primarily if the wound edges can be easily approximated. Split-thickness grafts are taken with a mechanical dermatome at a thickness which may vary from 8-12/1000 in., but they should contain a portion of the dermal layer to provide structural integrity and ease of manipulation. Whenever possible, donor sites should be in areas covered by clothing and attention given to future cosmetic considerations, but with extensive burns, all of the unburned skin may be harvested, including the scalp or the feet and excepting the face, hands, or genitalia. Preliminary subcutaneous infiltration of the skin with saline enhances the ability to obtain good grafts from the scalp or from an area where unresistent subcutaneous fat or underlying bony prominences interfere with good dermatome function. Donor sites may be harvested before or after excision of the wound, but the effort should be made to avoid going from an operative field which is contaminated to a clean donor area. Sheet grafts are fixed to the excised wound edges and to each other with interrupted, fine absorbable sutures and adhesive paper "Steristrips". Where donor skin is scarce, coverage of the area to be grafted may be enhanced by meshing of the skin graft with a mechanical meshing device which permits expansion of the skin graft to three or more times its original size. Meshed grafts may be sutured at the

w. c. Quinby,Jr. et al.: PrimaryExcisionand ImmediateWoundClosure wound edges and fastened to each other with metallic clips. They also may be preferable to sheet grafts if wound exudate or bleeding is particularly troublesome, since hematoma does not collect beneath them. In most areas the cosmetic results with meshed grafts are acceptable but somewhat inferior to sheet grafts.

g) Care of the Grafts. Motion of the graft on its bed, serum or hematoma beneath the graft, insufficient depth of wound excision, and surrounding or endogenous wound infection are the standard causes of graft failure. Grafted wounds may be treated "open" without dressings or by various "closed" dressing techniques. If the open technique is used, it is essential to minimize edema and accumulation of fluid beneath the grafts by expressing any fluid which collects beneath grafts by rolling a cotton swab over them during the first day or two until they are firmly adherent. This is particularly applicable to areas such as the anterior trunk or the face which cannot be immobilized but also is effective in extremities elevated above the horizontal and, in some instances, held up by transradial or transtibial traction Kwires. If the wound is to be treated with a "closed" dressing technique, small grafted areas that are difficult to immobilize may be managed by the construction of a stent or mold of the wound made of gauze which holds the graft firmly in place by the use of peripheral sutures tied over the stent. In larger areas, a primary single layer of coarsemeshed gauze which covers the graft is fixed around the periphery with a few sutures. Circular layers of gauze bandage are then applied, and pressure from a circumferential elastic bandage for eight to twelve hours also reduces fluid collection beneath the graft. It is advisable not to molest the dressings of minimally contaminated wounds for eight to ten days unless unexplained fever or other clinical indication arises. Control of wound contamination is enhanced by maintaining saturation of the dressings with 0.5070 silver nitrate solution. A recent experience with the use of minimally expanded meshed grafts in areas such as the axilla or groin, and fixation of six to eight layers of gauze to the wound bed by a "quilting" technique wherein the dressing is actually sutured to the wound bed at intervals not exceeding 2 in. has given excellent results. It also requires that the dressings be kept saturated with silver nitrate solution. The immobility provided by a large "quilted" dressing has permitted successful grafting of the back or buttocks, even though the patient actually lies upon the grafted wound. For two to three weeks following complete healing of grafted extremities a dependent position

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will cause edema to form and grafts to slough unless external elastic support is used. The primary use of allografts to close a wound where donor site skin is inadequate conforms in every way to the techniques of autografting. The intention is for stored grafts from a living donor or skin bank to vascularize and "take" as do autografts. Following vascularization, they become indistinguishable from autografts. Consequently, a careful record of their position in the grafted wound must be kept for identification at the time when they are to be removed. During the five to seven days after application, vascularized allografts may be stripped off the wound easily, but beyond that time they often are so intimately adherent to the wound bed that forceful use of an instrument such as a periosteal elevator is required for their removal. Manifestly, all allograft must be removed if replacement with autografts is to be successful.

IV. Comparative Results

Most of the factors which have reduced mortality rates in all surgical disease during the past 25 years have benefitted the burn patient. Although a controlled or randomized series is not available, 10 years of experience with burns of children under 16 years of age in the same hospital shows a reduction of mortality of burns in the ranges of 10-65% BSA from 10070 for unexcised burns to 2070 when it was used routinely. In both groups, 0.5% silver nitrate was the topical agent used. The interval from injury to wound closure was reduced to one-half that of the non-excised group. Functional benefits were dramatic in burns of the hand where both the number of hands that required operative reconstruction and the number of reconstructive procedures per hand were reduced to a third of those required in the unexcised group treated by debridement and late grafting [6].

V. The Massive Burn

In 1974 full-thickness burns which exceeded 70~ of BSA combined with total burn exceeding 80% BSA were fatal in most cases, fundamentally because closure of the burn wound could not be realized before malnutrition and sepsis supervened. Permanent closure of such extensive wounds with autografts required that donor sites be harvested

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r e p e a t e d l y at intervals o f the t w o - t h r e e weeks. Although meshing and expansion of autografts p e r m i t a n a r e a g r e a t e r t h a n the d o n o r site to be g r a f t e d at e a c h o p e r a t i o n , a n i n t e r v a l o f t w o - t h r e e weeks is r e q u i r e d f o r r e g e n e r a t i o n b e f o r e the d o n o r site c a n be r e h a r v e s t e d . I n deep b u r n s o f 5 0 % to 70~ B S A a l l o g r a f t s are e m p l o y e d for t e m p o r a r y w o u n d closure in o r d e r to a c c o m p l i s h t o t a l excision o f eschar. A l l o g r a f t s a r e r e p l a c e d b y a u t o g r a f t s f r o m r e g e n e r a t e d d o n o r sites p r i o r to the o n s e t o f the r e j e c t i o n p r o c e s s w h i c h begins w i t h i n t w o weeks. A n u n r e s o l v e d o p e n w o u n d is t h e r e f o r e a v o i d e d . W i t h m a s s i v e b u r n s the p a u c i t y o f a u t o g e n o u s skin is even m o r e crucial, a n d a d e l a y o f the r e j e c t i o n process p r o v i d e s m o r e t i m e f o r d o n o r sites to heal. A c c o r d i n g l y the tissue t y p i n g o f f a m i l y d o n o r s [1] a n d the use o f a n t i t h y m o c y t e g l o b u l i n ( A T G ) [171 at a dosage sufficient to suppress the r e j e c t i o n r e a c t i o n is i n s t i t u t e d . A l l o g r a f t r e j e c t i o n is t h e r e b y d e l a y e d u p to 30 days, a n d three o r m o r e harvests o f a u t o g r a f t are realized; at the first o p e r a t i o n a n d at least twice within a m o n t h t h e r e a f t e r . I n p r a c t i c e , a t the first o p e r a t i o n , as m u c h fullthickness b u r n is excised as c a n be closed with m e s h e d a u t o g r a f t s o b t a i n e d f r o m c r o p p i n g all a v a i l a b l e d o n o r sites. I m m u n o s u p p r e s s i o n is b e g u n 12 h b e f o r e the first a l l o g r a f t o p e r a t i o n . T h e d o s a g e o f A T G is a d j u s t e d a c c o r d i n g to t h e r o s e t t e c o u n t o f t h y m u s d e p e n d e n t l y m p h o c y t e s (T-cells) [17]. D u r i n g the next t w o t o t h r e e weeks, excisions o f m a j o r size are d o n e a n d the w o u n d closed with a l l o g r a f t s f r o m m a t c h e d donors, or from cadaver allografts from a Skin Bank if the f o r m e r are u n a v a i l a b l e . S u b s e q u e n t l y , as r e g e n e r a t e d d o n o r sites b e c o m e a v a i l a b l e , the vascularized allografts are removed and autografts a r e s u b s t i t u t e d for t h e m , or r e s i d u a l s m a l l unexcised areas m a y b e d i r e c t l y a u t o g r a f t e d . W i t h i n a m o n t h u n r e s o l v e d w o u n d s a r e b r o u g h t to a n a r e a o f less t h a n 15% B S A a n d A T G is d i s c o n t i n u e d . E x p e r i e n c e s with this p l a n o f t r e a t m e n t in 17 massively b u r n e d c h i l d r e n has s h o w n a survival rate o f m o r e t h a n 60070. A l t h o u g h c a r d i o r e s p i r a t o r y a n d nutritional advances and environmental control have also b e e n o f b e n e f i t , it is clear t h a t the use o f i m m u n o s u p p r e s s i o n has b e e n a m a j o r f a c t o r in t h e a c h i e v e m e n t o f i m p r o v e d results.

References 1. Amos DB, Cabrera G, Bias WB, MacQueen JM, Lancaster SL, Southworth JG, Ward FE (1970) The inheritance of human leucocyte antigens. III. The organization of specificities. In: Teraski PI (ed) Histo-compatibility Testing. Munksgaard, Copenhagen, p 259 2. Baxter CR (1971) Topical use of 1.0 percent silver sulfadiazine. In: Polk HC, Jr, Stone HH (eds) Contemporary burn management. Little, Brown & Co, Boston, pp 217-225 3. Bondoc CC, Burke JF (1971) Clinical experience with viable frozen skin bank. Ann Surg 174:371 4. Burke JF (1971) A bacteria controlled nursing unit and individual patient isolation facility. American Hospital Association's International Conference on Nosocomial Infections, p 216 5. Burke JF, Bondoc CC, Quinby WC, Jr (1974) Primary burn excision and immediate grafting: A method of shortening illness. J Trauma 14:389 6. Burke JF, Bondoc CC, Quinby WC, Jr, Remensnyder JP (1976) Primary surgical management of the deeply burned hand. J Trauma 16:593 7. Burke JF, Quinby WC, Bondoc CC, Cosimi AB, Russell PS, Szyfelbein SK (1975) Immunosuppression and temporary skin transplantation in the treatment of massive third degree burns. Ann Surg 182:183 8. Cope O, Langohr J, Moore FD, Webster R (1947) Expeditious care of full thickness burn wounds by surgical excision and grafting. Ann Surg 125:1 9. Hendren WH, Constable JD, Zawacki BE (1968) Early partial excision of major burns in children. J Ped Surg 3:445 10. Jackson D, Topley E, Carson JS, Lowburn EJL (1960) Primary excision and grafting of large burns. Ann Surg 152:167 11. Lewis RJ, Quinby WC, Jr (1973) Electrosurgical excision of full-thickness burns. Arch Surg 110:191 12. Macmillan BG (1958) Early excision of more than twenty-five percent of body surface in the extensively burned patient: an evaluation. Arch Surg 77:369 13. Moncrief JA, Linberg RB, Switzer WE, Prnitt BA (1966) Use of topical antibacterial therapy in the treatment of the burn wound. Arch Surg 92:558 14. Moyer C, Brentano L, Gravens DL, Margraf HW, Monafo WW (1965) Treatment of large human burns with 0.5 percent AgNO 3 solution. Arch Surg 90:812 15. Syzfelbein SK, Ryan JF (1974) Use of controlled hypotension for primary excision in an extensively burned child. Anesthesiology 41:501 16. Wells DB (1929) The treatment of electric burns by immediate resection and skin graft. Ann Surg 90:1069 17. Worfis HS, Cooper AG, Brown MD (1973) Inhibition of human lymphocyte rosetting by anti T sera. Nature 243:109 18. Young F (1942) Immediate skin grafting in the treatment of burns. Ann Surg 116:445 Dr. W. C. Quinby Harvard Medical School Massachusetts General Hospital 51 Blossom Street Boston, Massachusetts 02114, USA