945
Preliminary
Communications
CARBON-DIOXIDE LASER FOR EXCISION OF BURN ESCHARS NORMAN LEVINE STANLEY STELLAR* STANLEY M. LEVENSON RALPH GER Department of Neurosurgery, St. Barnabas Hospital, and Department of Surgery, Albert Einstein College of Medicine, Bronx, New York, U.S.A. in pigs, a continuouscarbon-dioxide laser was used to excise the eschar 24 hours after third-degree burning. Blood-loss was notably reduced compared with that expected for ordinary scalpel excision, and the fact that autografts " took " readily is an indication of the absence of significant damage to underlying tissue. In
Sum ary
experiments
wave
EXTENSIVE third-degree burning is always very serious and often lethal. Much of the resultant morbidity and mortality is due to infection originating in the irreparably damaged tissue. So long as devitalised tissue is present, infection is a threat. Although local antibiotic and chemotherapeutic agents have helped reduce bacterial colonisation and infection of the burned tissue, sepsis remains the principal cause of death in patients with extensive third-degree burns. Recovery and return of function in these patients is contingent on the earliest safe removal of the burn eschar and skin grafting. Because spontaneous sloughing of the deeply burned skin generally requires 21-35 days, early surgical excision of the eschar and skin grafting have been advocated. When the deep burn is extensive, this procedure involves prolonged anaesthesia and massive blood-loss and replacement (up to 40 units of whole blood for a single patient). We have investigated the use of lasers for the excision of third-degree burns. We were able to reduce the blood-loss accompanying the excision of deeply burned skin by excising the burn eschar with a continuous-wave carbon-dioxide laser (10-6 IL wavelength), which coagulates promptly small blood-vessels in the plane of excision without significantly damaging the underlying tissue. Skin grafting could be done immediately and successfully. Our experiments were done on 3-month-old Hampshire-Landrace pigs and have ranged from the excisions of small, circular, 5 cm. diameter, standardised third-degree contact burns to large (23 x 28 cm.) third-degree areas. Eschar was excised aseptically under pentobarbitone anxsthesia 24 hours after the burn injury. Experiments in which blood-loss was measured have shown that the laser excisions result in less than 5% of the blood-loss encountered when comparable areas are excised with the ordinary
scalpel. Excision of burn slough, by whatever means,
must
damage the underlying tissue as little as possible.
The of the condition of the tissue at the base of the wound is its ability to accept an immediately applied skin autograft. In pigs undergoing laser
critical
test
* Present address: Department of Neurosurgery, St. Barnabas Medical Center, Livingston, New Jersey, U.S.A.
excisions of large third-degree burns (from 18 x 23 cm. to 23 x 28 cm.), the " takes " of immediately applied autografts (0-002 in. thick) have been from 90% to 100%. The grafts have become vascularised promptly and have persisted intact during the 2 months of observation post-operatively. So far we have seen no gross evidence of systemic toxicity due to our use of the laser in removing burn eschars of up to 20% total body-surface area of the pigs. The laser thus seems to be a promising instrument for the excision of third-degree burn eschars. It offers the advantage of reducing blood-loss without causing significant injury to the underlying tissue or noticeable
systemic toxicity.
Autografts applied
to a
freshly
lased surface show excellent " takes " and persist in a normal fashion. Supported by grant from the Army Medical Research and Development Command DADA 17-70-C to the Albert Einstein College of Medicine, Yeshiva University and N.I.H. research career award 5-K6-GM-14,208 to S. M. L. The laser was kindly provided by the American Optical Corporation Research Laboratory (Dr. Thomas Polany, and Mr. Herbert C. Bredmeier), Framingham, Massachusetts, U.S.A. Requests for reprints should be addressed to S. S.
DIPHOSPHONATES AND PAGET’S DISEASE OF BONE ROGER SMITH R. G. G. RUSSELL MARGARET BISHOP Metabolic Unit, Nuffield Department of Orthopœdic Surgery,
University of Oxford The diphosphonate, CH3C(OH)(PO3 Summary HNa)2 (disodium etidronate), has been given at a daily oral dose of 20 mg. per kg. body-weight to 4 patients with biochemically active Paget’s disease. The increased alkaline phosphatase in plasma and the increased hydroxyproline in plasma and urine fell steadily to about half their initial value after three months’ treatment. This suggests that the diphosphonate
reduces the excessive bone turnover in this disease. Introduction
IN Paget’s disease of bone there is excess resorption and disorderly formation of bone which often results in severe deformities. Biochemical changes include an increase above normal in plasma-alkaline-phosphatase and in urinary total hydroxyproline (T.H.P.). Substances recently used in the medical treatment of this condition include calcitonin, 1,2 which inhibits bone resorption, and mithramycin,3which is a cytotoxic agent. Both appear to relieve bone pain and to reduce plasma-alkaline-phosphatase and urinary T.H.P. Both agents have to be administered by injection. Mithramycin, in particular, has serious side-effects. The diphosphonate compounds 4,6 offer an alternative approach to the therapy of Paget’s disease. These compounds bind to hydroxyapatite crystals and inhibit their growth and dissolution in vitro. 4-8 In animals certain diphosphonates inhibit bone resorption 4,7 and, at higher doses, inhibit bone mineralisation.8They are also effective by mouth. It therefore seemed logical to study their effect in Paget’s disease,