How secure are laparoscopically placed clips? An in vitro and in vivo study

Safety and Efficacy of Using Staplers and Vessel Sealing Devices for Laparoscopic Splenectomy: A Randomized Controlled Trial

Background. Laparoscopic splenectomy (LS) is considered the operation of choice on elective basis for managing patients with certain hematological disorders. Hemostatic control of the splenic pedicle is one of the crucial steps in LS. This study compares the safety and efficacy of using endoscopic staplers and vessel sealing devices to control the splenic pedicle in patients with nonsevere splenomegaly. Methods. Fifty-one consecutive patients with different blood disorders including idiopathic thrombocytopenic purpura (ITP), hypersplenism, and lymphoma were randomized for elective LS. Traditional steps of LS, via lateral approach, were followed, and pedicle control was done with either endovascular gastrointestinal anastomosis stapler (n = 26) or vessel sealing device (Ligasure) (n = 25). Results. No difference was noted with different splenic spans when using either methods of pedicle control (P = .145). The volume of blood loss was higher in the Ligasure group compared to the staplers group (182 mL vs 131 mL, respectively), but was not statistically significant (P = .249). Conversion to open was notably higher in the Ligasure group (P = .034), but the intraoperative complications were comparable in both groups (P = .357). Conclusion. The use of vessel sealing devices for splenic pedicle control has comparable surgical outcomes compared with the use of endoscopic staplers for LS, but with higher rate of conversion to open surgery.

In vitro holding strength of the laparoscopic Miller's knot compared with open Miller's knot, open surgeon's throw, and laparoscopic surgeon's throw in a vascular pedicle model

OBJECTIVE

To compare in vitro knot holding strength of the laparoscopic Miller's knot (LMK), open Miller's knot (MK), open surgeon's throw (Sx), and laparoscopic surgeon's throw (LSx) in a vascular pedicle model when used as the first throw for vascular ligation.

STUDY DESIGN

Experimental study.

SAMPLE POPULATION

Ten constructs each of the Miller's knot and surgeon's throw performed openly and laparoscopically with 2-0 polyglyconate suture.

METHODS

Knot holding strengths of the LMK, MK, LSx, and Sx knots were evaluated on balloon dilation catheters used as vascular pedicle models. Laparoscopic knots were tied in a laparoscopic box trainer. Knot constructs were pressure tested to failure. Results were compared by Kruskal-Wallis and Steel-Dwass comparisons.

RESULTS

Both MK and LMK had mean leakage pressures above 300 mm Hg. The MK leaked at higher pressure than all other knots, including the LMK (P < .001). The LMK leaked at greater pressures compared with the Sx and the LSx (P < .001). No difference was detected between leaking pressures of the Sx and the LSx (P = .226), with both leaking at pressures below 40 mm Hg.

CONCLUSION

The LMK created a more secure first throw compared with the Sx and leaked at supraphysiologic pressures.

CLINICAL SIGNIFICANCE

The LMK has excellent knot holding strength on a vascular pedicle model and may be further evaluated for clinical application.

Development of a new biodegradable operative clip made of a magnesium alloy: Evaluation of its safety and tolerability for canine cholecystectomy

BACKGROUND

Operative clips used to ligate vessels in abdominal operation usually are made of titanium. They remain in the body permanently and form metallic artifacts in computed tomography images, which impair accurate diagnosis. Although biodegradable magnesium instruments have been developed in other fields, the physical properties necessary for operative clips differ from those of other instruments. We developed a biodegradable magnesium-zinc-calcium alloy clip with good biologic compatibility and enough clamping capability as an operative clip. In this study, we verified the safety and tolerability of this clip for use in canine cholecystectomy.

METHODS

Nine female beagles were used. We performed cholecystectomy and ligated the cystic duct by magnesium alloy or titanium clips. The chronologic change of clips and artifact formation were compared at 1, 4, 12, 18, and 24 weeks postoperative by computed tomography. The animals were killed at the end of the observation period, and the clips were removed to evaluate their biodegradability. We also evaluated their effect on the living body by blood biochemistry data.

RESULTS

The magnesium alloy clip formed much fewer artifacts than the titanium clip, and it was almost absorbed at 6 months postoperative. There were no postoperative complications and no elevation of constituent elements such as magnesium, calcium, and zinc during the observation period in both groups.

CONCLUSION

The novel magnesium alloy clip demonstrated sufficient sealing capability for the cystic duct and proper biodegradability in canine models. The magnesium alloy clip revealed much fewer metallic artifacts in CT than the conventional titanium clip.

Evaluation of the Efficacy of the Electrosurgical Bipolar Vessel Sealer (LigaSure) Devices in Sealing Lymphatic Vessels

Various sources of ultrasonic and thermal energy have been developed to facilitate blood vessel ligation. However, their efficacy in sealing lymphatics has not been clearly established to date. We hypothesized that the electrosurgical bipolar vessel sealer (EBVS) produces reliable and durable sealing of large lymphatic vessels in a porcine model. Thoracic ducts from 4 adult pigs were explanted and sealed at multiple levels by using 3 different EBVS devices: LigaSure Atlas, XTD, and V. Fifteen seals (5 per group) were analyzed for sealing time and visual quality. Seal burst strength was measured by using a graduated pressure saline injection system. Twelve intact seals also underwent a histologic analysis. The mean overall burst strength of the seals was 271 78 mm Hg (127 to 360 mm Hg). The burst pressures in the 3 groups were not statistically different. The overall mean time to achieve a seal was 5.12.2 seconds (3 to 10 seconds). Seals were achieved significantly faster in the V group (4.10.6 seconds) compared with the Atlas (6.32.3 seconds) and XTD (6.4 2.6 seconds) groups. Qualitative seal assessment revealed minimal sticking and charring, a favorable degree of seal tissue clarity, and desiccation in the 3 groups. Histologic analysis demonstrated a fusion of lymphovascular channels with a complete obliteration of the lumens. We demonstrated that the use of EBVS results in a fast and effective sealing of large porcine lymphatic vessels. The seals created by all 3 devices burst at markedly supraphysiologic intraluminal pressures. Ongoing randomized human trials may prove the clinical benefits of the routine use of EBVS devices for various tissue dissections.

Pull-off characteristics of double-shanked compared to single-shanked ligation clips: an animal study

Background:

The use of surgical ligation clips is considered as the gold standard for the closure of vessels, particularly in laparoscopic surgery. The safety of clips is mainly achieved by the deep indentation of the metal bar with a high retention force. A novel double-shanked (DS) titanium clip was compared to two single-shanked clips with respect to axial and radial pull-off forces.

Methods:

In a porcine model (8 animals, 51±1 kg), arteries were prepared immediately after euthanisation, assigned to either a medium (2–4 mm; n=120) or a medium-large (3.5–7 mm; n=120) clip size group, and clipped with the appropriate clip size. After dissection, axial and radial pull-off forces were measured.

Results:

The axial pull-off force of the DS-Clip was higher than one single-shanked clip and comparable to the other single-shanked clip, and overall was linearly correlated to the cross-sectional area of the clip. The radial pull-off force of the DS-Clip was significantly higher than both single-shanked clips and, for the single-shanked clips, was correlated to the total clip thickness. The variation of radial pull-off force was lower for the DS-Clip due to a defined catch in the clip applier.

Conclusions:

The radial pull-off force was lower than the axial pull-off force in total and therefore appears to be the critical point of dislocation. Due to the higher total holding mass, the DS-Clip provided a clear advantage in this regard and might therefore decrease the dislocation rate. The catch in the applier increases the reproducibility in clip placement.

Clipless minilaparoscopic cholecystectomy: a study of 1,096 cases

PURPOSE

Low conversion rate, high safety, and good cosmetic result with less medical cost are chased by all laparoscopic surgeons. We used general laparoscopic instruments and combined with absorbable thread trying to perform a clipless minilaparoscopic cholecystectomy for benign gallbladder patients and got all the above-mentioned results.

SUBJECTS AND METHODS

From January 2008 to February 2011, 1096 minilaparoscopic cholecystectomies were performed for patients with uncomplicated or complicated benign gallbladder disease by our treatment team. The three-port technique with the help of an electrocautery hook, forceps, and suction was applied for laparoscopy cholecystectomy, and the cystic duct and vessels were ligated by absorbable thread rather than hemostasis clips and Harmonic(®) scalpels (Ethicon, Cincinnati, OH). The operative time, blood loss, subhepatic drain, conversion rate, drainage time, and hospital stay were reviewed and statistically analyzed.

RESULTS

Our conversion rate was 0.18%, which was much lower than those reported by many studies. The mean operating time was 28 minutes (range, 11-70 minutes). Mean blood loss was 12 mL (range, 5-200 mL). A subhepatic drain was placed in 63 patients, with a mean drainage time of 1.7 days (range, 1-6 days). The mean postoperative hospital stay was 2.5 days (range, 2-7 days). No postoperative bleeding, biliary leakage, intraabdominal infection, umbilical site infection, umbilical incision herniation, biliary duct or bowel injury, or mortality occurred.

CONCLUSIONS

Minilaparoscopic cholecystectomy using absorbable thread instead of clips and Harmonic scalpels offers a safe, effective, and economical surgical alternative for benign gallbladder patients.

Are we really doing better with Hem-o-lok in VATS?

BACKGROUND

  Due to advances in clip design, new types of surgical ligation clips are available that may reduce clip failure and improve function, but in the field of minimally invasive thoracic surgery, experience of using Hem-o-lok for pulmonary artery ligation is limited.

METHODS

  To assess risk factors and predictors of failure of the Hem-o-lok vascular clip, using vessels harvested from a porcine model.

RESULTS

  The Hem-o-lok clip had the worst holding strength compared to other clips. Its hemostatic ability for pulmonary vessels was far less stable compared with renal and hepatic vessels. The Hem-o-lok clip either leaked or burst when the vessel to which it was applied was cut flush. The clip became even more likely to fail if the vessel sleeve was mobilized too "clean."

CONCLUSION

  Our experiment proved that the use of Hem-o-lok clips in video-assisted thoracoscopic surgery (VATS) has some potential risk. We recommend that all possible care be taken when it is applied to pulmonary vessels during VATS. Leaving some tissues around vessels may increase the thickness of the vessel, which, in turn, may increase the holding strength.

Comparative study between ligature with thread or metallic clamping by means of laparoscopy with the purpose of experimental biliary obstruction in swines

PURPOSE

To induce a total extra-hepatic obstructive jaundice in swines, by ligation of the common bile duct by laparoscopic surgery.

METHODS

Eight swines of the Landrace race, 36-day-old, originated from the same matrix, distributed in two groups. Group A: was used titanium metal clip to the common bile duct ligation in three animals; group B: were ligated with 2-0 cotton thread in five animals.

RESULTS

The ligation of the biliary ducts was performed successfully in all animals, with easy identification of the common bile duct by laparoscopy. There weren't difficulties in the procedures, mainly due to the increased surgical field provided by the excellent quality of light and image of the appliance. The clinical signs of jaundice were evident in the animals in seven days. In group A, two animals showed bile duct perforation near the clip, probably due to ischemic necrosis, progressing to peritonitis and death. In group B, five animals showed obstructive jaundice without any amendment.

CONCLUSION

Under the conditions of this study, we therefore recommend the use of unabsorbed wires to experimental biliary obstruction, in order to avoid complications, such as ischemia and necrosis, followed by perforation of the wall of the bile ducts.

Clipless cholecystectomy: which sealer should be used?

BACKGROUND

The use of the Harmonic Scalpel (HS) for cystic duct ligation began with little data about its efficacy or safety. On the other hand, there is not any literature available about the use of PlasmaKinetic Sealer (PK) for closing the cystic duct in laparoscopic cholecystectomy (LC). Therefore, this study was designed to compare the efficacy and safety of HS and PK for achieving safe closure of the cystic ducts after LC.

METHODS

Ninety patients with symptomatic gallstone disease were enrolled in this prospective case control study. The patients were operated with laparoscopic technic and divided into three groups (n = 30) randomly. After the dissection of Calot's triangle, proximal cystic ducts on common bile ducts were sealed with single surgical clips (SC) in all groups, and in the first group, distal of the cystic ducts also was sealed with single SC and the gallbladders were removed with SC. In the second and third groups, distal of the cystic ducts were sealed with HS and PK, respectively. The gallbladders were removed as sealed cystic ducts with HS and PK. Then, gallbladders were connected to a transducer set and increasing pressure with saline was applied. The bursting pressures of gallbladders were measured and differences between the groups were calculated by using Student's t test. The value of P < 0.05 was accepted as significant.

RESULTS

In this study, the mean cystic duct bursting pressures were 332.46 ± 4.62 mmHg with SC, 326.56 ± 4.53 mmHg with PK, and 343.06 ± 4.28 mmHg with HS. Differences of the mean cystic duct bursting pressures between the groups were indicated the superior results of HS.

CONCLUSIONS

The results of this study indicated that HS is more effective than PK and as safe and effective as SC for cystic duct closure.

Day case laparoscopic cholecystectomy carried out using the harmonic scalpel: analysis of a standard procedure

INTRODUCTION

Our aim was to determine the efficiency and safety of laparoscopic cholecystectomy carried out using the harmonic scalpel as a day case procedure.

METHODS

A prospective study was done on patients presenting for Laparoscopic cholecystectomy. The harmonic scalpel was used with retrograde dissection. All patients were considered for discharge the same day unless considered medically unfit.

RESULTS

Laparoscopic cholecystectomy using the harmonic scalpel was carried out on 100 patients. Major complications were as follows: conversion to open procedure -1%, common bile duct injury -1%, and bile leak from the cystic duct stump -1%. Our same day discharge rate was 65%, and age more than 65 was the only independent predictor of overnight admission (P=0.009).

CONCLUSIONS

Laparoscopic cholecystectomy using the harmonic scalpel is associated with a low complication rate and a high-same-day discharge rate when carried out as a day case procedure.

Verification of clipless closure of cystic duct by harmonic scalpel

INTRODUCTION

The excellent results of harmonic scalpel (HS) for closure of blood vessels encouraged surgeons to use these instruments for cystic ducts. The use of HS on tissues other than blood vessels was started with little data about its efficacy or safety. Therefore, this study was designed to verify the safety and efficacy of HS for achieving safe closure of the cystic ducts after laparoscopic cholecystectomy.

MATERIALS AND METHODS

Sixty patients with symptomatic gallstone disease were enrolled in this prospective case control study. The patients were operated with laparoscopic technic and divided into two groups (n = 30). After the dissection of Calot's triangle, proximal cystic ducts on common bile ducts were sealed with single surgical clips (SC) in both groups. In the first group, distal of the cystic ducts was sealed with single SC and the gallbladders were removed with SC. In the second group, distal of the cystic ducts was sealed with HS and the gallbladders were removed as sealed cystic ducts with HS. Twenty-gauge catheters were inserted into the fundus of gallbladders in vitro and connected to the arterial line transducer set. A gradually increasing pressure was applied through a sphygmomanometer. The bursting pressures of the gallbladders were measured, and differences between HS and single SC groups were calculated with independent samples t-test. The value of P < 0.05 was accepted as significant.

RESULTS

The mean cystic duct bursting pressures in single SC and HS groups were 332.46 +/- 4.62 and 343.06 +/-4.28 mmHg, respectively. The mean values between the groups were found significant and indicated the superior results of HS.

CONCLUSIONS

HS sealer could be an alternative method for cystic duct closure, especially for avoiding the clip displacement and migration of the clip. Results of this study indicated that HS sealer was as reliable as single SC and it could be accepted as a standard closure technic.

Laparoscopic cholecystectomy with Harmonic scalpel

BACKGROUND

Laparoscopic cholecystectomy is the "gold standard" in the treatment of symptomatic gallbladder lithiasis. Nevertheless, some pitfalls are associated with the use of the monopolar hook, such as the risk of thermal injuries and biliary complications. By contrast, the ultrasonically activated scalpel, ie, Harmonic (Ethicon Endo Surgery INC - Johnson & Johnson Medical SPA, Somerville, NJ) in laparoscopic cholecystectomies has been increasingly used for dissection of the gallbladder and for division of vessels and the cystic duct, because it reduces the risk of thermal injuries.

METHODS

During a 2-year period, in a personal series of 95 consecutive patients, the Harmonic scalpel was used as the sole instrument for both division and dissection of the cystic artery and duct. The average length of inpatient stay, procedure duration, and complications were compared with the data of a homogenous control group of patients who were treated using monopolar electrosurgery and clips.

RESULTS

Neither major complications nor bile duct injuries were detected in either group, and no statistically significant difference was found between the 2 in terms of the incidence of postoperative complications. However, the mean operative time was significantly shorter in patients treated with the Harmonic scalpel.

CONCLUSION

The Harmonic scalpel is not only a safe and effective instrument but also a reliable substitute for clips because it provides complete hemobiliary stasis. Even if the study revealed no differences with regard to postoperative complications, the Harmonic scalpel represents a viable alternative because of the shorter operation time and cost savings that are inherent in a procedure using it as a single instrument.

Clipless laparoscopic cholecystectomy using the Harmonic scalpel for cirrhotic patients: a prospective randomized study

BACKGROUND

Improved laparoscopic experiences have made laparoscopic cholecystectomy (LC) feasible options for cirrhotic patients. This study aimed to compare the traditional method for LC with LC using the Harmonic scalpel in terms of safety and efficacy for cirrhotic patients.

METHODS

In this study, group A (60 patients) underwent LC by the traditional method (TM) with clipping of both the cystic duct and artery and dissection of the gallbladder by diathermy, and group B (60 patients) had LC performed using Harmonic scalpel (HS) closure and division of both the cystic duct and artery with dissection of the gallbladder by the HS. The perioperative data were recorded.

RESULTS

The operation with the Harmonic scalpel was performed in less time than TM (45.17 ± 10.54 vs. 69.71 ± 13.01 min; p = 0.0001). The intraoperative blood loss was significantly more with TM (133 ± 131.13 l vs. 70.13 ± 80.79 ml; p = 0.002). The conversion rate was 5% with TM and 3.3% with HS (p = 0.65). The incidence of gallbladder peroration was lower in the HS group (10% vs. 18.3%; p = 0.03). Bile leak was encountered in 1.7% with HS and 3.3% with TM (p = 0.45). The visual analog scale (VAS) for pain with HS on postoperative day 1 was (3.07 ± 2.02 vs. 4.4 ± 2.11 (p = 0.001).

CONCLUSION

For cirrhotic patients, LC still is more complicated and difficult than for patients without cirrhosis. The Harmonic scalpel provides complete hemobiliary stasis and is a safe alternative to the standard clipping of the cystic duct and artery for cirrhotic patients. It offers a shorter operative duration and less blood loss.

Comparative study between clipless laparoscopic cholecystectomy by harmonic scalpel versus conventional method: a prospective randomized study

BACKGROUND

This study was planned to compare the traditional method of laparoscopic cholecystectomy (LC) versus LC using harmonic as regard the safety and efficacy.

MATERIAL AND METHODS

This study included group A (70 patients) in whom LC was conducted using the traditional method (TM) by clipping both cystic duct and artery and dissection of gallbladder from liver bed by diathermy, and group B (70 patients) LC was conducted using harmonic scalpel (HS) closure and division of both cystic duct and artery and dissection of gallbladder from liver bed by HS. The intraoperative and postoperative parameters were collected including duration of operation, postoperative pain, and complications.

RESULTS

HS provides a shorter operative duration than TM (33.21 + 9.6 vs. 51.7 + 13.79, respectively, p = 0.001), with a significant less incidence of gallbladder peroration (7.1% vs. 18.6, p = 0.04) and less rate of conversion to open cholecystectomy but not reach a statistical significance. The amount of postoperative drainage is significantly less in HS (29 + 30 vs. 47.7 + 31, p = 0.001). No postoperative bile leak was encountered in HS, but it occurred in 2.9% of patients in TM. VAS in HS at 12 h postoperative was 3.25 + 1.84 vs 5.01 + 1.2 (p = 0.001) and at 24 h postoperative was 3.12 + 1.64 vs. 4.48 + 1.89 (p = 0.001).

CONCLUSION

HS provides a complete hemobiliary stasis and is a safe alternative to stander clip of cystic duct and artery. It provides a shorter operative duration, less incidence of gallbladder perforation, less postoperative pain, and less rate of conversion to open cholecystectomy.

Clipless laparoscopic cholecystectomy by ultrasonic dissection

BACKGROUND

Ultrasonically activated devices have been used in gallbladder dissection in the laparoscopic cholecystectomy with encouraging results. The aim of this study was to compare between the safety and efficacy of the harmonic shears and the commonly used clip and cautery technique in achieving safe closure and division of the cystic duct in the laparoscopic cholecystectomy.

METHODS

In this prospective study, 120 patients with symptomatic gallstone disease were randomly assigned to either the harmonic scalpel laparoscopic cholecystectomy group (HS group=60 patients) where closure and division of the cystic duct was achieved solely by the harmonic shears or the clip and cautery laparoscopic cholecystectomy group (C&C group=60 patients).

RESULTS

Neither minor nor major bile leaks were encountered in either group. Similarly, no bile-duct injuries were encountered in the present study. The incidence of gallbladder perforation was statistically significantly higher in the C&C group, compared to the HS group (30 vs. 10%, respectively; P=0.002). The median operative time was statistically significantly shorter in the HS group than in the C&C group (32 vs. 40 minutes, respectively; P=0.000). No statistically significant difference was found in the incidence of postoperative complications between both groups.

CONCLUSIONS

The harmonic shears are as safe and effective as the commonly used clip and cautery technique in achieving safe closure and division of the cystic duct in the laparoscopic cholecystectomy. Further, it provides a superior alternative to the currently used high-frequency monopolar technology in terms of shorter operative time and lower incidence of gallbladder perforation.

Multidetector computed tomographic characteristics of nonabsorbable polymer versus titanium ligature clips in a vascular model

OBJECTIVE

Multidetector cardiac computed tomography is commonly performed to evaluate coronary bypass grafts, but titanium clips result in significant image artifact. Multidetector cardiac computed tomographic characteristics of newly developed nonabsorbable polymer clips are unknown. This study was undertaken to compare the image characteristics of polymer clips and titanium clips applied to a vascular model.

METHODS

A vascular model was created with two porcine internal thoracic arteries. Branches were ligated with 5 titanium clips on one vessel and 6 polymer clips on the other. Vessels were imaged under pressure with normal saline solution in a 16-detector computed tomographic scanner. Image intensity was quantified in absolute Hounsfield units for clips and adjacent lumen and then normalized to the average lumen intensity.

RESULTS

No difference in absolute intensity was found between polymer clips and adjacent lumen (polymer clip 1021.2 +/- 19.0 absolute Hounsfield units, adjacent lumen 1001.7 +/- 15.7 absolute Hounsfield units, P = .095). A statistically significant difference was noted between titanium clips and adjacent lumen (titanium clips 3408.8 +/- 177.3 absolute Hounsfield units, adjacent lumen 1072.7 +/- 52.1 absolute Hounsfield units, P < .0001). A statistically significant difference was also noted between titanium and polymer clips (P < .0001).

CONCLUSION

The use of polymer clips in coronary bypass grafts should result in significantly improved multidetector cardiac computed tomographic image quality.

Are titanium clips for control of the renal hilar vessels as unsafe as generally presumed?

Controlled ligation and division of renal vessels is a critical step during any nephrectomy procedure. It is generally been presumed that titanium clip ligation of renal vessels is risky and insecure. We report our experience over 5 years with ligaclips 10-mm titanium clips for secure ligation of renal hilum during laparoscopic nephrectomy. Titanium clips of 10 mm were used to secure renal vessels in 86 patients. We managed to get across the entire width of renal vein with a 10-mm titanium clip by crimpling the vein with the help of the clip applicator before firing the clips. In all except 2 cases ligaclips alone were enough to ensure secure occlusion of renal hilum. There was no incidence of slippage or dislodgement of clips applied on renal vessels. On cost analysis, it was found that the Hem-o-lok clip and gastrointestinal anastomosis stapling device were approximately 6-fold and 12-fold costlier than ligaclips. We also reviewed literature on different modalities available for renal hilar control during laparoscopic nephrectomy.

Thoracoscopic Thoracic Duct Sealing with LigaSure in Two Children with Refractory Postoperative Chylothorax

PURPOSE

Chylothorax is an uncommon complication of cardiac surgery. We report two cases of the thoracoscopic management of persistent postoperative chylothorax by thoracic duct thermofusion and section with the LigaSure device.

MATERIALS AND METHODS

A 6-year-old boy and a 3-year-old girl developed persistent chylothorax following an aortic coarctation repair and a Fontan procedure, respectively. The former presented with a left chylothorax due to direct surgical injury, and the latter, a right chylothorax due to indirect lymphatic rupture secondary to increased venous pressure. In both patients, voluminous chylous drainage persisted for more than 3 weeks despite maximal medical treatment. Ultimately, a right thoracoscopic coagulation and section of the thoracic duct with the 5-mm LigaSure device was performed. The LigaSure is a computer-controlled bipolar diathermy system designed to seal blood vessels up to 7 mm in diameter, with no specific recommendations regarding the lymphatics.

RESULTS

The lymph leakage ceased within 2 days in the first patient and immediately in the second one, with no recurrence after oral intake resumption on day 5. Both patients are free of recurrence at 1 year.

CONCLUSION

Thoracoscopic coagulation and section of the thoracic duct above the diaphragm with the LigaSure device appears to be a simple, effective, and safe therapeutic option for treatment of refractory postoperative chylothorax in children.

Comparison of Holding Strength of Suture Anchors for Hepatic and Renal Parenchyma

BACKGROUND AND PURPOSE

Various laparoscopic devices have been described for suture anchoring during solidorgan parenchymal closure. Application of these devices expedites the closure of parenchymal defects and minimizes ischemia time. We compared different technologies as suture anchors for parenchymal closure.

MATERIALS AND METHODS

A tensometer was used to determine the amount of tension necessary to dislodge each of five different clips from Vicryl suture alone or against two different substrates (fresh pig kidney and liver) with and without an intervening pledget. The clips investigated were the Lapra-Ty (Ethicon), Endoclip II (US Surgical), small Horizon Ligating Clips (Weck), Hem-o-lok Medium Polymer Clips (Week), and a novel Suture-clip (Applied Medical). ANOVA and two-sided Fisher's exact test provided statistical analysis.

RESULTS

The force required to dislodge the Lapra-Ty clip from bare suture for both 0 and 1 Vicryl (7.0 N) was approximately fourfold the force required to dislodge the Endoclips or the 5-mm or 10-mm Hem-o-lok clips (p<0.01). When clips were applied to suture running through renal or liver parenchyma, the novel Suture-clip required the greatest tension to dislodge (P<0.01), followed by the Horizon and Lapra-Ty clips. There were no statistically significant differences in the tension required to dislodge a given clip from the two parenchymal substrates or in the presence or absence of a pledget.

CONCLUSIONS

In our experimental model, the Suture-clip, Lapra-Ty, and Horizon clips required significantly greater tension to dislodge than the Hem-o-lok and Endoclip clips. The addition of a pledget did not improve tension resistance.

Comparison of Nonabsorbable Polymer Ligating and Standard Titanium Clips with and without a Vascular Cuff

PURPOSE

To compare the efficacy of nonabsorbable polymer ligating (NPL) and titanium clips applied with and without a 1-mm vascular cuff at physiologic and supraphysiologic pressures.

MATERIALS AND METHODS

An in vitro equine-vessel model was created to test clip occlusion strength. Ten-millimeter NPL and standard Ti clips were applied to veins (10 mm) and arteries (10, 6, and 5 mm) with and without a 1-mm cuff and tested until they held a pressure of 300 mm Hg (veins) or 760 mm Hg (arteries) for 2 minutes or leaked.

RESULTS

The NPL clip was statistically more secure on 10-mm veins with and without a cuff, 10-mm arteries with and without a cuff, and 6-mm arteries with a cuff than was the Ti clip. Leaving a 1-mm cuff resulted in a statistically higher leak point in all vessels tested except the 6-mm arteries secured with the Ti clip.

CONCLUSIONS

The NPL clip was more secure than the Ti clip on larger arteries and veins. A 1-mm vascular cuff enhances the security of both NPL and Ti clips in vessels of all sizes. The NPL clip is secure and reliable in securing both arteries and veins.

Control of the Renal Artery and Vein with the Nonabsorbable Polymer Ligating Clip in Hand-Assisted Laparoscopic Donor Nephrectomy

BACKGROUND

The large and variable size of the renal vein has prompted most surgeons to select linear stapling devices to secure the vein during laparoscopic donor nephrectomy. Although effective, these stapling devices have a potential for misfire. Use of the nonabsorbable polymer ligating (NPL) clip during laparoscopic donor nephrectomy provides increased graft vessel length compared with the stapling device, and the NPL clip has a locking mechanism which may increase security compared with standard titanium clips. The objective of this study was to evaluate the safety and efficacy of the NPL clip for control of the renal artery and vein during hand-assisted laparoscopic donor nephrectomy (HALDN).

METHODS

A retrospective chart review of 50 consecutive HALDN patients was conducted where two parallel NPL clips were used to control both the renal artery and vein. Information collected included demographic data, operative and postoperative data, and complications.

RESULTS

Mean donor age was 33.4 years and body mass index was 25.8 kg/m2. Mean operative time was 266.0 min, mean hospital stay was 3.2 days, and mean warm ischemia time was 123.3 seconds. There were no transfusions, open conversions, or complications related to use of the NPL clip. A US 16,300 dollars disposable cost savings was seen during this 1-year period alone.

CONCLUSIONS

The NPL clip was 100% safe and effective in controlling the renal artery and vein during HALDN, allowed for additional vessel length, and resulted in a disposable cost savings of US 362 dollars per patient.

Matching supraclavicular fields to the extent of axillary surgery in women prescribed radiotherapy for early stage carcinoma of the breast

AIMS

To determine (1) if the lower border of a standard anterior radiotherapy field to the supraclavicular fossa matches the upper limit of level II/III axillary dissection; and (2) whether standard lung blocks in patients prescribed axillary radiotherapy shield target axillary tissue in women with breast cancer.

MATERIALS AND METHODS

Between 1999 and 2001, 30 women with breast cancer undergoing level II/III axillary dissection had titanium clips placed to define the upper and medial limits of surgery. At radiotherapy planning, a supraclavicular fossa field similar to that described in the UK START trial protocol was simulated, with head twist applied to position the inferior field border (50% isodose) 1 cm below and parallel to the lower border of the clavicle. The field position was recorded on X-ray film. The location of the most superior axillary clip was measured in relation to this inferior field border on the X-ray film. The location of the most medial clip was measured in relation to the lung/chest wall interface.

RESULTS

The median distance between the most superior clip and the inferior border of the supraclavicular field was 3.6 cm (0.8-6.9 cm), representing significant underlap in all cases. In addition, five out of 30 (17%) patients had surgical clips over 2.0 cm medial to the lung/chest wall interface, suggesting that medial lymph nodes in an undissected axilla would be shielded by standard lung blocks in patients prescribed axillary radiotherapy.

CONCLUSION

Current standard radiation fields to the supraclavicular fossa, as applied in this study, leave apical axillary lymph nodes untreated in a high proportion of patients. Standard lung shielding, as applied in this study to patients simulated for axillary radiotherapy, protect medial axillary lymph nodes in a few patients. A change in practice is recommended.

Surgical clip found in duodenal ulcer after laparoscopic cholecystectomy

The wide use of surgical clips in laparoscopic surgery has led to a variety of complications. We describe two cases in which a surgical clip was incorporated into a duodenal ulcer after laparoscopic cholecystectomy. The presenting symptom was acute gastrointestinal bleeding. Both patients were treated endoscopically, and the bleeding stopped after the clip was removed from the ulcer base. Although the mechanism by which a surgical clip migrates into the duodenum is unclear, we recommend meticulous Calot's triangle dissection and removal of any wandering or misplaced clips. Endoscopic removal is recommended when a surgical clip is discovered in a bleeding ulcer.

Vessel Sealing Using a Pulsed Bipolar System and Open Forceps

We evaluated the vessel-sealing ability of one application of a pulsed plasma kinetic (PK) electrosurgical device on skeletonized vessels up to 7 mm in diameter to withstand sustained pressure of 300 mm Hg using bench and animal models. Forty-six porcine specimens and 66 abattoir vessels (112 total) were pressure tested after sealing with a pulsed PK system. Of these, 108 (96%) met the criterion of 300 mm Hg pressure held for 10 seconds without leaking. The PK system open forceps effectively closes vessels and maintains closure at a pressure level sufficient for clinical use. The device is more effective than clips, sutures, and staples.

The relationship between five kinds of laparoscopic knots and five types of suture materials and histological findings in tissues: an experimental study on rabbits

The aim of the current study was to examine the slipping and the tightening of laparoscopic knots with various kinds of sutures, as well as the histologic alterations in tissues. Fifty rabbits and five kinds of sutures were used-silk, polyglactine-910 (Vicryl), Polydioxanone (PDS), Polyglycol (Dexon), and cat-gut chromic-and five laparoscopic knots were used-Tayside, Roeder, Melzer, Cross, and Blood. The knots were performed extracorporeally and were used to ligate a part of the omentum. Sliding and tightening of the knots were evaluated. The omentum, the suture, and the knots were checked 10 days and 1 month after operation. Histologic examination was performed 1 month after surgery. Polyglactine-910 (Vicryl) and silk were the most qualitative sutures used in Tayside, Roeder, and Blood knots and the least harmful for the tissues. Catgut chromic and Polydioxanone (PDS) were the most defective sutures. The most efficient laparoscopic slipknots are Tayside, Roeder, and Blood, especially when constructed with silk and polyglactine-910 (Vicryl).

Ligadura com algodão e com grampos de titânio em artérias de cães: estudo experimental em máquina simuladora de pressão

O desenvolvimento da cirurgia video-laparoscópica trouxe a necessidade de tornar convencional a ligadura artérial com grampos de titânio para a diminuição do tempo operatório. Com o objetivo de investigar e comparar a ligadura artérial com algodão zero e com um, dois e três grampos de titânio, foram utilizadas 80 artérias de 20 cães da espécie Canis Familiaris. De cada cão, utilizaram-se as artérias axilares direita e esquerda e femorais direita e esquerda, que foram distribuídas em quatro grupos, mediante sorteio prévio e rodízio. Após a dissecção artérial e ligadura, as artérias foram submetidas a uma pressão de 100 mmHg e de 300 mmHg, e a uma pulsação de 70 batimentos por minuto, conseguida por meio de uma máquina simuladora da pressão artérial. Houve extravasamento em três artérias, todas pertencentes ao grupo de ligadura com um grampo de titânio. Este extravasamento é estatisticamente significante e ocorreu em até 15 minutos após o início de funcionamento da máquina. Com os resultados, conclui-se que a ligadura artérial com um grampo de titânio tem maior probabilidade de extravasar do que a ligadura com dois ou três grampos de titânio, e a ligadura com fio de algodão zero, em cães. Não há diferença entre a ligadura artérial com fio de algodão e com dois ou três grampos de titânio, quando submetidas a pressão de 300 mmHg e pulsação de 70 batimentos por minuto, em cães.

Use of a computer-controlled bipolar diathermy system in radical prostatectomies and other open urological surgery

BACKGROUND

Ligasure is a computer-controlled bipolar diathermy system, designed to optimally seal vessels < or = 7 mm in diameter. The aim of the present study was to evaluate its application to open urological surgery.

METHODS

The Ligasure device was used in 32 consecutive open surgical cases, including 25 radical prostatectomies, five radical nephrectomies, one partial nephrectomy and one nephro-ureterectomy. All procedures were performed using standard surgical techniques, with the exception that the Ligasure device was used for haemostasis. This included pelvic lymphatics and prostatic, adrenal, gonadal and aberrant obturator vessels, as well as vessels associated with the ureter, vasa, seminal vesicles, peri-renal fat, peritoneum and peri-adrenal tissues. Vessels > 7 mm in diameter, such as the renal artery, were ligated. In no patients were haemostatic clips used.

RESULTS

In all procedures, vessels and other structures < 7 mm were successfully sealed using the Ligasure device. For some structures, such as the prostatic pedicles and the seminal vesicles, the Ligasure device was much easier to apply than haemostatic clips. Use of the Ligasure device reduced the operating time (mean: 113 min vs 135.5 min; P < 0.001) and blood loss (mean: 529 mL vs 642 mL; P < 0.02) for radical prostatectomies. No intraoperative or postoperative blood transfusions were required. There were no postoperative haemorrhages, lymph leakage or lymphocoeles. Median inpatient hospital stay was 7 days (range: 6-9 days) and no patients required readmission.

CONCLUSION

The Ligasure, device was safe and easy to use in major urological procedures.

Chief resident experience with laparoscopic cholecystectomy

Resident competence in both open and laparoscopic cholecystectomy (LC) has been a concern among general surgeons. Laparoscopic surgery was late in coming at many surgical residency programs in the United States, and many residents have graduated with limited experience in LC. We are chief residents who were fortunate enough to start our training when LC was first introduced at our institution in 1990. This report summarizes our experience with LC in our chief year, during which we performed LC on 147 patients. The average operating time was 37 minutes (range, 12-82 minutes). Six patients (4%) required conversion to an open procedure. There were three complications (2 postoperative cystic duct leaks and 1 intraoperative common bile duct injury) for an overall complication rate of 2%. There was no mortality. It is our conclusion that graduating chief residents with 5 years' exposure to LC may perform the procedure with a complication rate comparable to that reported in the current literature. Insuring that graduating chief residents have adequate training in open cholecystectomy may become a more pressing issue in the near future.

Safety evaluation of laparoscopically applied clips

We have evaluated in vitro, the security of laparoscopically applied clips, through two commercially available clip appliers: the Endo Clip II (US Surgical) and the Ligaclip (Ethicon). The clip performance was tested with respect to dislodgment and leakage. Dislodgment was attempted both transversely and at 45 degrees with respect to the main axis of the tubular structures tested. The mean maximum force (N = 24) necessary to dislodge a clip applied to silicone tubing (2.1, 2.4, 3.2 mm o.d.) and porcine vascular tissue was measured. The maximum force needed to transversely dislodge a clip applied to silicone tubing, ranged from 262 +/- 9 g (2.1 mm) to 315 +/- 11 g (3.2 mm) for the Endo Clip II applier, while the values for the Ligaclip were 220 +/- 28 g (2.1 mm) and 273 +/- 11 g (3.2 mm), respectively. To achieve dislodgment at 45 degrees pull, corresponding forces of 294 +/- 8 g (2.1 mm) and 369 +/- 14 g (3.2 mm) for the Endo Clip II, and 254 +/- 14 g (2.1 mm) and 297 +/- 13 g (3.2 mm) for the Ligaclip (N = 24) were required. Transverse dislodgment forces, for clips applied to tissue, were 556 +/- 146 g for the Endo Clip II and 356 +/- 170 for the Ligaclip (N = 6). Leakage tests were also performed under pulsatile blood circulation at mean pressure of approximately 800 mm Hg. No tested clips applied to either silicone tubing or tissue allowed for any blood leakage. The dislodgment test showed that the Endo Clip II exhibits superior performance compared to the Ligaclip, based on the fact that it requires more force for transverse and semiaxial dislodgment. In the leakage test, both clip appliers performed equivalently.

Bile duct injury and bile leakage in laparoscopic cholecystectomy

The introduction of laparoscopic cholecystectomy has been associated with an increased incidence of bile duct injury. This review presents the incidence of bile duct injury in reported series and examines the role of the learning curve and other contributing factors. There is good evidence to suggest that, with adequate training and experience, the incidence of biliary injury can be reduced to a level comparable to that of open cholecystectomy. Continued audit is required to ensure that the low complication rates achieved in selected centres with wide experience are reproduced by the surgical community in general.

Complications of therapeutic laparoscopy

Laparoscopic surgery holds great promise as a technique for reducing hospital stay and convalescence. Although advantages in hospital cost cannot be shown for all such procedures, improvements in technique and operator experience will undoubtedly improve the situation. Analysis of the pertinent physiologic aspects and complication rates indicates that laparoscopy is not minimally invasive, but rather exposes the patient to many of the risks normally incurred by open procedures. Enthusiasm for the use of these techniques must be tempered by good judgment and scientific evidence supporting equivalent or better long-term results at equal or lower rates of morbidity and mortality.

A new minimally invasive technique for cholecystectomy. Subxiphoid "minimal stress triangle": microceliotomy

OBJECTIVE

The authors devised a minimally invasive technique for cholecystectomy via microceliotomy that provides safety attainable with the open conventional approach and postoperative results comparable to laparoscopic cholecystectomy.

SUMMARY BACKGROUND DATA

Laparoscopic cholecystectomy has evolved as a minimally invasive outpatient procedure. Patients can return rapidly to preoperative status with minimal postoperative morbidity and pain, and the small scar size is cosmetically desirable. Unfortunately, there are reports of serious intraoperative complications, including injury to blood vessels, bowel, and the bile ducts, caused by failure to identify structures properly. The conventional cholecystectomy technique currently is relegated to patients on whom the laparoscopic procedure cannot be performed.

METHODS

Cholecystectomy was performed through a 3-cm transverse high subxiphoid incision in the "minimal stress triangle." The location, anterior to Calot's triangle, was critical in providing a direct vertical view of the biliary ducts during dissection. Direct view cholecystectomy was performed using endoscopic instruments without pneumoperitoneum. Postoperative data were compared with both laparoscopic and open cholecystectomy results.

RESULTS

Using the microceliotomy technique in the ambulatory setting, cholecystectomy was performed successfully in 99.3% (N = 143) of cases. Biliary leakage beyond the third postoperative day was caused by failure of clips or obstruction to bile flow. The postoperative morbidity, acceptability of scar, and analgesic requirements compare favorably with other techniques. Microceliotomy is cost effective. Portal hypertension is a contraindication for this procedure.

CONCLUSIONS

The microceliotomy approach offers a viable, safe, and cost-effective alternative to the laparoscopic technique for cholecystectomy, especially when facilities for laparoscopy are not available or when the laparoscopic procedure cannot be performed.

Comparative study of the holding strength of slipknots using absorbable and nonabsorbable ligature materials

The holding and tensile characteristics of five extracorporeal slipknots in relation to absorbable and nonabsorbable ligature materials have been evaluated in a standardized in vitro test rig. The knots studied: Tayside, Roeder, Melzer (modified Roeder), Cross square, and Blood knots were tied with the following materials: silk, polyamide, Dacron, polydioxanone (PDS), and lactomer (Polysorb). Following construction and slippage (run down) to a fixed-diameter loop around a cylinder, the knots were locked (tightened) using a standardized force after which they were removed from the test rig and subjected to holding strength (force required to induce reverse slippage) and other tensile characteristics (stress, strain, elasticity) by a tensiometer. Analysis of the data has demonstrated the following: (1) The safest slip knots (resist slippage) are the Tayside, Melzer, and Roeder knots tied with lactomer and Dacron. (2) The holding strengths of the Cross square and Blood knots are weak with all ligature materials tested. (3) Polydioxanone is a safe ligature material for the Melzer and Tayside but not the Roeder knot. (4) Extracorporeal slipknots tied with silk and polyamide are less secure than the equivalent knots tied with Dacron, lactomer, and polydioxanone.

Extracorporeal knot tying using an atraumatic Babcock clamp

Extracorporeal knot tying is a method of avoiding the difficult and time-consuming skill of intracorporeal knot tying and can be equally effective. An endoscopic Babcock clamp can be used instead of the usual knot-pusher devices so that the suture material does not become dislodged. The Babcock clamp lays the knot flat and applies equal traction on each end of the suture.

Quantitation of force to dislodge endoscopic ligation clips: EndoClip II vs. Ligaclip ERCA

The mean forces required to dislodge two types of endoscopic ligation clips from both porcine cystic ducts and silicone tubing were quantitated. The two types of endoscopic clips were EndoClip II and Ligaclip ERCA. Following application of the clips, the force required to dislodge the clips in both a perpendicular direction and a longitudinal direction was determined. The mean levels of force required to dislodge the EndoClip II clips in both directions were significantly (p < or = 0.01) greater than those required to dislodge the Ligaclip ERCA clips.

Comparison of titanium and absorbable polymeric surgical clips for use in laparoscopic cholecystectomy

The use of hemostatic surgical clips is crucial in laparoscopic surgery. Metal clips can cause significant interference with computerized tomography, may have poor holding power, and may erode into important anatomic structures. Polymeric absorbable clips, which have advantages over metallic clips, are evaluated in this study. In vitro and in vivo studies were undertaken to evaluate the hold force, rate of degradation, tissue reactivity and safety of absorbable polymeric clips. Absorbable and titanium clips were applied across excised canine cystic ducts and both axial and transverse pull-off forces were measured. In the second phase, absorbable clips were implanted subcutaneously into male rats and the strength remaining within the clips was measured after 7, 10, 14, or 21 days. In phase 3, 30 pigs were randomized into six groups and each animal underwent a laparoscopic cholecystectomy. The cystic duct and artery were ligated with absorbable polymeric clips (experimental group) or titanium clips (control group). Animals were sacrificed at 7, 14, or 28 days and a celiotomy was performed. Intraabdominal adhesions were assessed and scored. The force required to dislodge the absorbable clip was significantly greater than for metallic clips for both axial and transverse forces. Absorbable clip strength retention decreased over time as expected with a retention of 11% original strength by the 21st day. Adhesions were highest when bile spillage occurred, but did not differ significantly between either clip type. Absorbable polymeric clips were hemostatically effective in this laparoscopic model and may offer advantages over metallic clips.

Laparoscopic gastrojejunostomy: a case presentation

Laparoscopic gastrojejunostomy is demonstrated as an alternative to open gastric bypass procedures. We performed the operative procedure safely and with reasonable anesthesia time, using stapling devices. It is hoped that further patient benefit will be obtained from this laparoscopic procedure in the future.