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Effects of argon beam coagulation on split thickness skin graft survival in the swine model
Bums (1994) 20, (2), 115-117 Printed in Great Britain
115
Effects of argon beam coagulation on split thickness skin graft survival in the swine model* J. w . Canady I, J. M. Hiebert z, M. M. Mani z P. Briscoe 2 and S. A. T h o m p s o n 3 ~Section of Plastic and Reconstructive Surgery, Department of Surgery, 1'3Department of Otolaryngology, ~Department of Orthopedics, University of Iowa Hospitals and Clinics, Iowa City, Iowa and 2Section of Plastic and Reconstructive Surgery, Department of Surgery, Kansas University Medical Center, Kansas City, Kansas, USA
Argon beam coagulation (ABC) uses argon gas to evacuate blood in an operative field and simultaneously to transport a coagulating electric current to bleeding sites. This allows a 'no touch' method of coagulation which is faster, more precise, and less destructive than conventional electrocautery. The technique has been used to reduce blood loss in liver surgery, trauma surgery and neck dissections. In this study, the effect of ABC treatment of the recipient graft beds on the survival of split thickness skin grafts was assessed in pigs, testing the hypothesis that ABC treatment of the recipient bed would have no adverse effect on skin graft survival. Nine 20 kg mixed breed pigs had split thickness skin grafts raised on each side of the paraspinoas area. The graft beds on one side were prepared using ABC and the contralateral side served as controls. The percentage of graft survival on the ABC treated sides was compared to control graft survival on the other side at 12 days postsurgery. Our results confirm the hypothesis that treatment of the recipient bed with ABC does not adversely affect the survival of split thickness skin grafts.
Materials and methods Nine, 20 kg, mixed breed pigs were used in the study. The animals were housed according to Handbook for the Use of Animals in Research and Education in the animal care facility at Kansas University Medical Center. Grafting was done under a combination of ketamine, 20 mg/kg, and inhalant anaesthesia (halothane, dosage to effect). Each animal was given a prophylactic intraoperative dose of a penicillin antibiotic, 10 mg/kg. Three grafts (7.6 x 12.7 cm) were harvested on each side of the paraspinous area of each of the nine pigs using a Padget electric dermatome set at 0.20 mm thickness. Three graft beds on one side of each animal (27 beds in total) were treated for haemostatic control with the ABC (Figure I) at the setting of 40 (Bard ABC System 6000, courtesy of Bard Electro Medical Systems, Birtcher Corporation Englewood, Colorado prior to replacement of the split thickness grafts.
Introduction Argon Beam Coagulation (ABC) has become a clinically useful technique for achieving haemostasis and may be a superior method of coagulation in certain cases. Unlike lasers, ABC uses argon gas to evacuate the operative field and simultaneously to transport current to bleeding sites. This results in lower thermal temperatures at the cautery site and therefore less tissue destruction in the tissue being coagulated. Another advantage is that this 'no touch' technique allows a large field of small bleeding vessels (up to 3 mm) to be coagulated rapidly and completely. The uses and advantages of ABC have already been described in general surgery and in head and neck surgery1-4. Because of its efficacy in achieving rapid coagulation in relatively large bleeding fields, we felt that ABC may have value in reducing blood loss and operating time during tangential excision and grafting of bum wound injuries. However, no data existed on the survival of split thickness skin grafts after treatment of the recipient beds with ABC. This study was designed to assess skin graft survival on recipient beds treated with ABC as compared to grafts placed using standard methods of graft-bed treatment.
Figure 1. Preparation of the graft beds with ABC (upper side). *Presentedat the 1990 InternationalSymposiumon Plastic Surgery, Brisbane,Australia,August, I990. 9 1994 Butterworth-HeinemannLtd 0305-4179/94/020115-03
Note that haemostasis is achieved more effectively than in the conventionallyprepared beds (lower side).
116
Figure 2. Recipient beds prior to graft placement. The ABC treated beds are on the side of the animal toward the top of the photograph.
Haemostasis in the 27 control graft beds was achieved using direct pressure for 5 min. Larger bleeding vessels which did not stop with pressure alone were individually coagulated with Standard electric cautery. Figure2 shows experimental and control graft beds immediately prior to application of the grafts. Each graft was meshed on a 1.0--1.5 expansion template using a Tanner mesher. The graft was then returned to its original bed in a slightly expanded state and sutured in place with a 3-0 nylon running suture. No external dressings were used. Postoperatively, the animals were housed individually. Photographs were taken just prior to graft placement and on postoperative days 1, 2, 4, 6, 10 and 12. On the twelfth postoperative day the animals were killed and each skin graft was inspected. Portions of the graft were judged to have survived if they were adherent to the graft bed at the time of death. Non-adherent portions of the grafts were trimmed and the area of the adherent graft was calculated. Graft survival was determined by dividing the adherent area of the graft by the total area of the graft5. Percentage graft survival, expressed as a decimal to control for variation in the sizes of the grafts, was subjected to statistical analysis. Results
The mean fraction of surviving graft for the experimental (ABC) group was 0.844. The mean fraction of surviving graft in the control group was 0.663. Repeated Measures Analysis of Variance (ANOVA) was used to compare the overall treatment effects on control and ABC treated sides. The data was tested for interaction between overall effects and treatment sites. There was no significant interaction between graft survivial within a treatment group and the treatment site (P = 0.1525). From the F test of the ANOVA it was determined that the grafts placed on ABC treated beds had significantly more surviving grafted skin than the controls (P= 0.0067). Discussion
The Argon Beam Coagulation system is a device which allows efficient coagulation of vessels up to 3 mm in
Burns (1994) Vol. 20/No. 2
diameter with reduced surrounding tissue damage. This is possible because the handpiece of this device produces a pressurized stream of argon gas which blows pooled blood away from the haemorrhaging vessel. This allows a lower wattage to be applied to the severed end of the vessel to achieve a seal. The same gaseous stream which is evacuating the field also serves as a conduit for the electrical current used in the coagulation process. Thus, this system is not a laser; rather, it represents a different and potentially more efficient application of the usual coagulation technology. Although the experimental group treated with ABC showed an overall increased skin graft survival when subjected to statistical analysis, there was a relatively wide variation in the per cent of surviving tissue within each treatment group. Although it could be argued that split thickness skin grafts placed on a dean, dry recipient bed should have nearly 100 per cent take, this is not necessarily a reasonable expectation in large animal models. Physical trauma to the grafts as the animals moved about their cages may have caused some local injury which contributed to this variation. External dressings were not used because previous experience has shown that such dressings, while helpful in some human patients, are often a source of aggravation to animal subjects with resultant additional trauma. Also, it would have been impossible with animals of this size to remove the bolsters for graft inspection without anaesthesia. Adherence of a graft to a recipient bed is a reliable indicator of graft survival at 12 days postsurgery. Tavis et al.5 have determined that 72 h is the maximum time a graft may stick to its bed because of mechanical adhesion. Beyond 3 days, microvascular ingrowth secures the graft in place, reflecting the extent of viable tissue s. A possible explanation for the increased survival of skin grafts in the experimental group may be that the reduction of haematoma under the graft permitted neovascularization to take place more efficiently. Argon beam coagulation proved to be a rapid .and effective way to achieve haemostasis in this model. The recipient beds which were pretreated with ABC appeared drier and had less exudate during the first few days of graft healing. Statistical analysis of the data in this study determined that pretreatment of graft beds with ABC did not adversely affect skin graft survival when compared to grafts placed using standard preparation methods. Encouraged by the evidence that the recipient bed was satisfactory, we plan to determine if the use of ABC in the preparation of graft beds in humans will make grafting more effective by reducing blood loss and decreasing operative time in acute bum wound surgery.
References
1 RuschVW, SchmidtR, Shoji Y and FujimuraY. The use of the Argon Beam Electrocoagulator for performing pulmonary wedge resections.Ann Thorac Surg 1990; 49: 287. 2 Stylianos S, I--IoffmanMA, Rohrer RJ, Jacir NN, Bhan I and Harris BH. Experimental reduction hepatectomy with the Argon Beam Coagulator. Presented at the World Association of HPB Surgery.Third World Congress. London, UK, 1990.
Canady et al.: Effects of Argon beam coagulation 3 Stylianos S, Hoffmann MA, Jacir NN and Harris BH. Sutureless hemisplenectomy. ] PedialrSurg 1991; 26: 97. 4 Ward P, Castro DJ, Ward S. A significant new contribution to radical head and neck surgery. Arch Otol 1989; 115: 921. 5 Tavis NJ, Thornton JW, Hamey JH, Woodroof EA and Bartlett RH. Graft Adherence to de-epithelialized surfaces: a comparative study. Ann Surg 1976; 184: 594. Paper accepted 19 A u g u s t 1993.
Correspondenceshouldbeaddressedto. John W. Canady, E230 General Hospital, University of Iowa Hospitals and Clinics, Iowa City, IA, 52242, USA.
117
Churchill Livingstone is p r o u d to a n n o u n c e that we now publish the American Volume of
~ , ......
The Journal of Hand Surgery the official journal of the American Society for Surgery of the Hand We continue to publish the British and European volume of The Journal of Hand Surgery which is the official journal of the British Society for Surgery of the Hand and the Federation of European Societies for Surgery of the Hand.
Both volumes are dedicated to the needs of hand, plastic, reconstructive, orthopaedic and general surgeons who are concerned with restoring function to the hand and upper limb. Both volumes attract authoritative contributions of outstanding quality from distinguished experts worldwide. They reflect the wealth of information available and guarantee rapid access to the latest research, techniques, trends and ideas available today.
The world of hand surgery is now at your fingertips! Twelve issues per year are available to you - six issues of the American Volume and six issues of the British/European volume. Each issue includes peer-reviewed original articles, influential editorials, conference/symposia dates, book reviews, clear photographs and illustrations, case studies, detailed coverage of new techniques, full-length review articles and much more.
Discounted rates are available to members of BSSH/ASSH/FESSH as well as to individual non-members who wish to subscribe to both volumes. For further information write to: Churchill Livingstone, Robert
Stevenson House, 1-3 Baxter's Place, Edinburgh EH1 3AF, UK or Churchill Livingstone Inc, 650 Avenue of the Americas, New York, NY 10011, USA. P-MI~
Churchill Livingstone Medical Division of Longman Group UK I,td Registered office 5 Benlinck Street. London W 1M 5RN
115
Effects of argon beam coagulation on split thickness skin graft survival in the swine model* J. w . Canady I, J. M. Hiebert z, M. M. Mani z P. Briscoe 2 and S. A. T h o m p s o n 3 ~Section of Plastic and Reconstructive Surgery, Department of Surgery, 1'3Department of Otolaryngology, ~Department of Orthopedics, University of Iowa Hospitals and Clinics, Iowa City, Iowa and 2Section of Plastic and Reconstructive Surgery, Department of Surgery, Kansas University Medical Center, Kansas City, Kansas, USA
Argon beam coagulation (ABC) uses argon gas to evacuate blood in an operative field and simultaneously to transport a coagulating electric current to bleeding sites. This allows a 'no touch' method of coagulation which is faster, more precise, and less destructive than conventional electrocautery. The technique has been used to reduce blood loss in liver surgery, trauma surgery and neck dissections. In this study, the effect of ABC treatment of the recipient graft beds on the survival of split thickness skin grafts was assessed in pigs, testing the hypothesis that ABC treatment of the recipient bed would have no adverse effect on skin graft survival. Nine 20 kg mixed breed pigs had split thickness skin grafts raised on each side of the paraspinoas area. The graft beds on one side were prepared using ABC and the contralateral side served as controls. The percentage of graft survival on the ABC treated sides was compared to control graft survival on the other side at 12 days postsurgery. Our results confirm the hypothesis that treatment of the recipient bed with ABC does not adversely affect the survival of split thickness skin grafts.
Materials and methods Nine, 20 kg, mixed breed pigs were used in the study. The animals were housed according to Handbook for the Use of Animals in Research and Education in the animal care facility at Kansas University Medical Center. Grafting was done under a combination of ketamine, 20 mg/kg, and inhalant anaesthesia (halothane, dosage to effect). Each animal was given a prophylactic intraoperative dose of a penicillin antibiotic, 10 mg/kg. Three grafts (7.6 x 12.7 cm) were harvested on each side of the paraspinous area of each of the nine pigs using a Padget electric dermatome set at 0.20 mm thickness. Three graft beds on one side of each animal (27 beds in total) were treated for haemostatic control with the ABC (Figure I) at the setting of 40 (Bard ABC System 6000, courtesy of Bard Electro Medical Systems, Birtcher Corporation Englewood, Colorado prior to replacement of the split thickness grafts.
Introduction Argon Beam Coagulation (ABC) has become a clinically useful technique for achieving haemostasis and may be a superior method of coagulation in certain cases. Unlike lasers, ABC uses argon gas to evacuate the operative field and simultaneously to transport current to bleeding sites. This results in lower thermal temperatures at the cautery site and therefore less tissue destruction in the tissue being coagulated. Another advantage is that this 'no touch' technique allows a large field of small bleeding vessels (up to 3 mm) to be coagulated rapidly and completely. The uses and advantages of ABC have already been described in general surgery and in head and neck surgery1-4. Because of its efficacy in achieving rapid coagulation in relatively large bleeding fields, we felt that ABC may have value in reducing blood loss and operating time during tangential excision and grafting of bum wound injuries. However, no data existed on the survival of split thickness skin grafts after treatment of the recipient beds with ABC. This study was designed to assess skin graft survival on recipient beds treated with ABC as compared to grafts placed using standard methods of graft-bed treatment.
Figure 1. Preparation of the graft beds with ABC (upper side). *Presentedat the 1990 InternationalSymposiumon Plastic Surgery, Brisbane,Australia,August, I990. 9 1994 Butterworth-HeinemannLtd 0305-4179/94/020115-03
Note that haemostasis is achieved more effectively than in the conventionallyprepared beds (lower side).
116
Figure 2. Recipient beds prior to graft placement. The ABC treated beds are on the side of the animal toward the top of the photograph.
Haemostasis in the 27 control graft beds was achieved using direct pressure for 5 min. Larger bleeding vessels which did not stop with pressure alone were individually coagulated with Standard electric cautery. Figure2 shows experimental and control graft beds immediately prior to application of the grafts. Each graft was meshed on a 1.0--1.5 expansion template using a Tanner mesher. The graft was then returned to its original bed in a slightly expanded state and sutured in place with a 3-0 nylon running suture. No external dressings were used. Postoperatively, the animals were housed individually. Photographs were taken just prior to graft placement and on postoperative days 1, 2, 4, 6, 10 and 12. On the twelfth postoperative day the animals were killed and each skin graft was inspected. Portions of the graft were judged to have survived if they were adherent to the graft bed at the time of death. Non-adherent portions of the grafts were trimmed and the area of the adherent graft was calculated. Graft survival was determined by dividing the adherent area of the graft by the total area of the graft5. Percentage graft survival, expressed as a decimal to control for variation in the sizes of the grafts, was subjected to statistical analysis. Results
The mean fraction of surviving graft for the experimental (ABC) group was 0.844. The mean fraction of surviving graft in the control group was 0.663. Repeated Measures Analysis of Variance (ANOVA) was used to compare the overall treatment effects on control and ABC treated sides. The data was tested for interaction between overall effects and treatment sites. There was no significant interaction between graft survivial within a treatment group and the treatment site (P = 0.1525). From the F test of the ANOVA it was determined that the grafts placed on ABC treated beds had significantly more surviving grafted skin than the controls (P= 0.0067). Discussion
The Argon Beam Coagulation system is a device which allows efficient coagulation of vessels up to 3 mm in
Burns (1994) Vol. 20/No. 2
diameter with reduced surrounding tissue damage. This is possible because the handpiece of this device produces a pressurized stream of argon gas which blows pooled blood away from the haemorrhaging vessel. This allows a lower wattage to be applied to the severed end of the vessel to achieve a seal. The same gaseous stream which is evacuating the field also serves as a conduit for the electrical current used in the coagulation process. Thus, this system is not a laser; rather, it represents a different and potentially more efficient application of the usual coagulation technology. Although the experimental group treated with ABC showed an overall increased skin graft survival when subjected to statistical analysis, there was a relatively wide variation in the per cent of surviving tissue within each treatment group. Although it could be argued that split thickness skin grafts placed on a dean, dry recipient bed should have nearly 100 per cent take, this is not necessarily a reasonable expectation in large animal models. Physical trauma to the grafts as the animals moved about their cages may have caused some local injury which contributed to this variation. External dressings were not used because previous experience has shown that such dressings, while helpful in some human patients, are often a source of aggravation to animal subjects with resultant additional trauma. Also, it would have been impossible with animals of this size to remove the bolsters for graft inspection without anaesthesia. Adherence of a graft to a recipient bed is a reliable indicator of graft survival at 12 days postsurgery. Tavis et al.5 have determined that 72 h is the maximum time a graft may stick to its bed because of mechanical adhesion. Beyond 3 days, microvascular ingrowth secures the graft in place, reflecting the extent of viable tissue s. A possible explanation for the increased survival of skin grafts in the experimental group may be that the reduction of haematoma under the graft permitted neovascularization to take place more efficiently. Argon beam coagulation proved to be a rapid .and effective way to achieve haemostasis in this model. The recipient beds which were pretreated with ABC appeared drier and had less exudate during the first few days of graft healing. Statistical analysis of the data in this study determined that pretreatment of graft beds with ABC did not adversely affect skin graft survival when compared to grafts placed using standard preparation methods. Encouraged by the evidence that the recipient bed was satisfactory, we plan to determine if the use of ABC in the preparation of graft beds in humans will make grafting more effective by reducing blood loss and decreasing operative time in acute bum wound surgery.
References
1 RuschVW, SchmidtR, Shoji Y and FujimuraY. The use of the Argon Beam Electrocoagulator for performing pulmonary wedge resections.Ann Thorac Surg 1990; 49: 287. 2 Stylianos S, I--IoffmanMA, Rohrer RJ, Jacir NN, Bhan I and Harris BH. Experimental reduction hepatectomy with the Argon Beam Coagulator. Presented at the World Association of HPB Surgery.Third World Congress. London, UK, 1990.
Canady et al.: Effects of Argon beam coagulation 3 Stylianos S, Hoffmann MA, Jacir NN and Harris BH. Sutureless hemisplenectomy. ] PedialrSurg 1991; 26: 97. 4 Ward P, Castro DJ, Ward S. A significant new contribution to radical head and neck surgery. Arch Otol 1989; 115: 921. 5 Tavis NJ, Thornton JW, Hamey JH, Woodroof EA and Bartlett RH. Graft Adherence to de-epithelialized surfaces: a comparative study. Ann Surg 1976; 184: 594. Paper accepted 19 A u g u s t 1993.
Correspondenceshouldbeaddressedto. John W. Canady, E230 General Hospital, University of Iowa Hospitals and Clinics, Iowa City, IA, 52242, USA.
117
Churchill Livingstone is p r o u d to a n n o u n c e that we now publish the American Volume of
~ , ......
The Journal of Hand Surgery the official journal of the American Society for Surgery of the Hand We continue to publish the British and European volume of The Journal of Hand Surgery which is the official journal of the British Society for Surgery of the Hand and the Federation of European Societies for Surgery of the Hand.
Both volumes are dedicated to the needs of hand, plastic, reconstructive, orthopaedic and general surgeons who are concerned with restoring function to the hand and upper limb. Both volumes attract authoritative contributions of outstanding quality from distinguished experts worldwide. They reflect the wealth of information available and guarantee rapid access to the latest research, techniques, trends and ideas available today.
The world of hand surgery is now at your fingertips! Twelve issues per year are available to you - six issues of the American Volume and six issues of the British/European volume. Each issue includes peer-reviewed original articles, influential editorials, conference/symposia dates, book reviews, clear photographs and illustrations, case studies, detailed coverage of new techniques, full-length review articles and much more.
Discounted rates are available to members of BSSH/ASSH/FESSH as well as to individual non-members who wish to subscribe to both volumes. For further information write to: Churchill Livingstone, Robert
Stevenson House, 1-3 Baxter's Place, Edinburgh EH1 3AF, UK or Churchill Livingstone Inc, 650 Avenue of the Americas, New York, NY 10011, USA. P-MI~
Churchill Livingstone Medical Division of Longman Group UK I,td Registered office 5 Benlinck Street. London W 1M 5RN