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New atraumatic rounded-edge surgical needle holder jaws
HOWIDOIT
New Atraumatic
Rounded-Edge Holder Jaws
Surgical Needle
Michael R. Abidin, MD, Michael A. Towler, MSME, John G. Thacker, Phn, Geofrey D. Nochimson, Walter McGregor, BS, MBA, Richard F. Edlich, MD, PhD, Charlottesville,Virginia
A new atraumatic smooth needle holder jaw with rounded edges that does not damage synthetic monofilament sutures is described herein. These rounded edges were created by mechanical filing of the sharp edges of smooth needle jaws. Compression of the monofilament suture between the needle holder jaw with sharp edges reduces the suture breaking strength compared with that of control sutures. A quality control method has been devised to detect the potentially damaging sharp edges of smooth needle jaws that can be easily implemented by needle holder manufacturers.
MD,
holder was tested as delivered, whereas the outer edges of the smooth jaws of the other needle holder were subjected to mechanical filing to change the right angle configuration of its edges to a rounded configuration (Figure 1). The lever arms of both needle holders were adjusted so that their jaws exerted the same clamping forces (10.8 newtons) when the first opposing teeth of their ratchet mechanism interlocked. Each needle holder compressed a 6-Omonofilament nylon suture (lot no. C2989K; Ethicon, Somerville, NJ) for 15 seconds with sufficient force to engage the first opposing interlocking teeth of its ratchet mechanism. The breaking strength of the clamping suture was measured by the Tensile Tester (Instron, Canton, MA) [I]. The statistical analysis of the data was determined by the Student’s t test. RESULTS
I
n an earlier study, we reported that clamping of sutures by smooth needle holder jaws without teeth was atraumatic and did not alter the mechanical strength of sutures [I]. The results of these mechanical performance studies were in sharp contrast to the clinical experiences of some surgeons, who reported that clamping sutures with smooth needle holder jaws apparently cut the suture, thereby markedly reducing its strength. This study confirms that some smooth needle holder jaws tested by our laboratory do indeed damage sutures. This sutural damage is due to the sharp outer edges of the smooth needle jaws whose edges have a 90-degree angular contiguration. Mechanical filing of these sharp edges converts them into a smooth rounded configuration that does not damage sutures. Quality control measures for atraumatic smooth needle holder jaws have been devised that can easily be implemented by needle holder manufacturers, ensuring that their smooth jaw surfaces will be atraumatic to sutures. MATERIAL
AND METHODS
The needle holders used in this study were 6-inch Crile Wood needle holders (Snowden Pencer, Tucker, GA) with smooth tungsten carbide jaw inserts. One needle From the Department of Plastic Surgery, University of Virginia School of Medicine and the Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia. Supported in part by a grant from the Texaco Philanthropic Foundation, White Plains, New York. Requests for reprints should be addressed to Richard F. Edlich, MD, University of Virginia School of Medicine, Department of Plastic Surgery, Box 332, Charlottesville, Virginia 22908.
Clamping of monofilament nylon between the smooth jaws of the needle holder not subjected to mechanical filing resulted in a marked reduction in the breaking strength of the 6-Omonofilament nylon sutures (p
During the last decade, surgeons have gradually changed to continuous suture techniques for vascular anastomoses and repair of arteriotomies and venotomies, as well as abdominal fascial closures [2,3]. This increased usage of continuous suture techniques has resulted from the availability of narrow diameter monofilament synthetic sutures that passed easily through tissue. In addition, the obvious advantage of superior operative speed is another beneficial aspect of continuous closure techniques over that of the interrupted suture techniques. They are, however, certain recognized limitations of the continuous suture technique that should be emphasized. A single defect in the continuous suture may lead to disruption of the entire continuous suture closure, whereas a comparable single defect in one interrupted suture loop will usually have no significant clinical impact. Although suture manufacturers exercise great care in manufacturing sutures with a uniform and reliable breaking strength, there is a possibility that physical damage to the suture can occur from the time the suture is removed from its package until it is manipulated and tied by the
THE AMERICAN JOURNAL OF SURGERY
VOLUME 157 FEBRUARY 1989
241
6-O
MONOFILAMENT
Figure 1. Top, compressionof sutures between the needle holder Jaws wlth smooth tungsten carbkle inserts with sharp outer edges (A) can damage synthetic monofilament sutures. Bottom, mechanlcal filing of the sharp edges of smooth tungsten carblde Inserts results In rounded outer edges (B) that do not damage sutures compressed by the needle jaws.
Control
surgeon. Such inadvertent damage to the suture may not be recognized before the wound is closed, only to result in disruption of the continuous suture and wound during the early postoperative period. A potential source of damage to the synthetic monofilament sutures exists when the suture is clamped between the smooth needle holder jaws with sharp outer edges. Monofilament nylon sutures subjected to the sharp outer edges of the tungsten carbide inserts undergo a marked reduction in breaking strength that could contribute to early wound disruption. This sutural damage can be prevented by mechanical grinding of the outer sharp edges of the smooth tungsten carbide inserts, resulting in a rounded edge. Clamping the suture with the smooth jaws with rounded edges was atraumatic with no demonstrable damage to the suture’s breaking strength. The presence of sharp edges of smooth tungsten carbide inserts in needle holder jaws can be detected by a simple quality control test that involves a thin 0.0132 mm plastic film (Dow Chemical, Midland, MI) placed between the needle holder jaws. When the jaws are compressed with sufficient force to engage the first opposing interlocking teeth of the ratchet mechanism, the sharp edges of the smooth jaw inserts cut the thin plastic film.
242
THE AMERICAN JOURNAL OF SURGERY
:n: I .9 f I .o
NEEDLE
Rounded Edge HOLDER
Shdro Edgi
INSERTS
lgure 2. The breaklng strength of 6-O monofilament nylon suture subjected to compressionby tungsten carblde smooth Inserts with sharp outer edges was slgnlflcantlyless than that of the control sutures. Clamping the 6-O monofllament nylon sutures between the smooth tungsten Inserts wlth rounded edges dld not alter the suture breaklng strength.
The presence of a cut in the plastic film can be easily visualized by stretching the film in directions perpendicular to the linear cuts, thereby enhancing the width of the defects in the film. A needle holder with jaw inserts that cut the film should be subjected to mechanical filing that rounds its outer jaw edges. REFERENCES 1. Stamp CV, McGregor W, Rodeheaver GT, Thacker JG, Towler MA, Edlich RF. Surgical needle damage to sutures. Am Surg 1988; 54: 300-6. 2. Nichols WK, Stanton M, Silver D, Kritzer WR. Anastomotic aneurysms following lower extremity revascularization. Surgery 1980; 88: 366-73. 3. Poole CV Jr. Mechanical factors in abdominal wound closure: the prevention of fascial dehiscence. Surgery 1985; 97: 631-9.
VOLUME 157
FEBRUARY 1989
New Atraumatic
Rounded-Edge Holder Jaws
Surgical Needle
Michael R. Abidin, MD, Michael A. Towler, MSME, John G. Thacker, Phn, Geofrey D. Nochimson, Walter McGregor, BS, MBA, Richard F. Edlich, MD, PhD, Charlottesville,Virginia
A new atraumatic smooth needle holder jaw with rounded edges that does not damage synthetic monofilament sutures is described herein. These rounded edges were created by mechanical filing of the sharp edges of smooth needle jaws. Compression of the monofilament suture between the needle holder jaw with sharp edges reduces the suture breaking strength compared with that of control sutures. A quality control method has been devised to detect the potentially damaging sharp edges of smooth needle jaws that can be easily implemented by needle holder manufacturers.
MD,
holder was tested as delivered, whereas the outer edges of the smooth jaws of the other needle holder were subjected to mechanical filing to change the right angle configuration of its edges to a rounded configuration (Figure 1). The lever arms of both needle holders were adjusted so that their jaws exerted the same clamping forces (10.8 newtons) when the first opposing teeth of their ratchet mechanism interlocked. Each needle holder compressed a 6-Omonofilament nylon suture (lot no. C2989K; Ethicon, Somerville, NJ) for 15 seconds with sufficient force to engage the first opposing interlocking teeth of its ratchet mechanism. The breaking strength of the clamping suture was measured by the Tensile Tester (Instron, Canton, MA) [I]. The statistical analysis of the data was determined by the Student’s t test. RESULTS
I
n an earlier study, we reported that clamping of sutures by smooth needle holder jaws without teeth was atraumatic and did not alter the mechanical strength of sutures [I]. The results of these mechanical performance studies were in sharp contrast to the clinical experiences of some surgeons, who reported that clamping sutures with smooth needle holder jaws apparently cut the suture, thereby markedly reducing its strength. This study confirms that some smooth needle holder jaws tested by our laboratory do indeed damage sutures. This sutural damage is due to the sharp outer edges of the smooth needle jaws whose edges have a 90-degree angular contiguration. Mechanical filing of these sharp edges converts them into a smooth rounded configuration that does not damage sutures. Quality control measures for atraumatic smooth needle holder jaws have been devised that can easily be implemented by needle holder manufacturers, ensuring that their smooth jaw surfaces will be atraumatic to sutures. MATERIAL
AND METHODS
The needle holders used in this study were 6-inch Crile Wood needle holders (Snowden Pencer, Tucker, GA) with smooth tungsten carbide jaw inserts. One needle From the Department of Plastic Surgery, University of Virginia School of Medicine and the Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia. Supported in part by a grant from the Texaco Philanthropic Foundation, White Plains, New York. Requests for reprints should be addressed to Richard F. Edlich, MD, University of Virginia School of Medicine, Department of Plastic Surgery, Box 332, Charlottesville, Virginia 22908.
Clamping of monofilament nylon between the smooth jaws of the needle holder not subjected to mechanical filing resulted in a marked reduction in the breaking strength of the 6-Omonofilament nylon sutures (p
During the last decade, surgeons have gradually changed to continuous suture techniques for vascular anastomoses and repair of arteriotomies and venotomies, as well as abdominal fascial closures [2,3]. This increased usage of continuous suture techniques has resulted from the availability of narrow diameter monofilament synthetic sutures that passed easily through tissue. In addition, the obvious advantage of superior operative speed is another beneficial aspect of continuous closure techniques over that of the interrupted suture techniques. They are, however, certain recognized limitations of the continuous suture technique that should be emphasized. A single defect in the continuous suture may lead to disruption of the entire continuous suture closure, whereas a comparable single defect in one interrupted suture loop will usually have no significant clinical impact. Although suture manufacturers exercise great care in manufacturing sutures with a uniform and reliable breaking strength, there is a possibility that physical damage to the suture can occur from the time the suture is removed from its package until it is manipulated and tied by the
THE AMERICAN JOURNAL OF SURGERY
VOLUME 157 FEBRUARY 1989
241
6-O
MONOFILAMENT
Figure 1. Top, compressionof sutures between the needle holder Jaws wlth smooth tungsten carbkle inserts with sharp outer edges (A) can damage synthetic monofilament sutures. Bottom, mechanlcal filing of the sharp edges of smooth tungsten carblde Inserts results In rounded outer edges (B) that do not damage sutures compressed by the needle jaws.
Control
surgeon. Such inadvertent damage to the suture may not be recognized before the wound is closed, only to result in disruption of the continuous suture and wound during the early postoperative period. A potential source of damage to the synthetic monofilament sutures exists when the suture is clamped between the smooth needle holder jaws with sharp outer edges. Monofilament nylon sutures subjected to the sharp outer edges of the tungsten carbide inserts undergo a marked reduction in breaking strength that could contribute to early wound disruption. This sutural damage can be prevented by mechanical grinding of the outer sharp edges of the smooth tungsten carbide inserts, resulting in a rounded edge. Clamping the suture with the smooth jaws with rounded edges was atraumatic with no demonstrable damage to the suture’s breaking strength. The presence of sharp edges of smooth tungsten carbide inserts in needle holder jaws can be detected by a simple quality control test that involves a thin 0.0132 mm plastic film (Dow Chemical, Midland, MI) placed between the needle holder jaws. When the jaws are compressed with sufficient force to engage the first opposing interlocking teeth of the ratchet mechanism, the sharp edges of the smooth jaw inserts cut the thin plastic film.
242
THE AMERICAN JOURNAL OF SURGERY
:n: I .9 f I .o
NEEDLE
Rounded Edge HOLDER
Shdro Edgi
INSERTS
lgure 2. The breaklng strength of 6-O monofilament nylon suture subjected to compressionby tungsten carblde smooth Inserts with sharp outer edges was slgnlflcantlyless than that of the control sutures. Clamping the 6-O monofllament nylon sutures between the smooth tungsten Inserts wlth rounded edges dld not alter the suture breaklng strength.
The presence of a cut in the plastic film can be easily visualized by stretching the film in directions perpendicular to the linear cuts, thereby enhancing the width of the defects in the film. A needle holder with jaw inserts that cut the film should be subjected to mechanical filing that rounds its outer jaw edges. REFERENCES 1. Stamp CV, McGregor W, Rodeheaver GT, Thacker JG, Towler MA, Edlich RF. Surgical needle damage to sutures. Am Surg 1988; 54: 300-6. 2. Nichols WK, Stanton M, Silver D, Kritzer WR. Anastomotic aneurysms following lower extremity revascularization. Surgery 1980; 88: 366-73. 3. Poole CV Jr. Mechanical factors in abdominal wound closure: the prevention of fascial dehiscence. Surgery 1985; 97: 631-9.
VOLUME 157
FEBRUARY 1989