Laparoscopic Hemostasis

Hemostasis in the closed environment imposed by minimal access surgery is one obstacle blocking progression to more complex intracorporeal techniques. The ability to maintain a clear surgical field allows complex tasks such as suturing to be performed (23).

Some of the instruments discussed in this chapter are essential components to the surgeon's hemostatic armamentaria. There are five basic modalities at the surgeon's disposal for the augmentation of local hemostasis (Table 1). These are in addition to the methods of systemically altering the physiologic clotting parameters that might facilitate hemostasis.

Vascular pedicles have been safely ligated and divided by autostaplers for two decades (24,25). The concern for arteriovenous fistula development is certainly worth consideration, especially if both structures are taken en bloc (26). The vascular autosta-pling devices are theoretically designed to separate the artery and the vein prior to fixing into the staple delivery mode. The laparoscopic autostaplers have little clinical data yet to support their widespread applicability. Laboratory studies indicate that it is crucial to anticipate the trajectory necessary for delivering the 12 mm device to the targeted pedicle vasculature. The wrong approach results in untoward tension on the vessels during the engagement process. During transperitoneal laparoscopic nephrectomies, anterior axillary line portals both cranially or caudad to the laparoscope portal were effective to autostaple the renal artery and vein (27). Clip application during pedicle dissection has been addressed in the general surgical literature (28,29).

There are proponents for loop ligation and for titanium clipping. Urologically, the laparoscopic nephrectomy animal model indicated that clips were associated with more blood loss than autostapling techniques (31).

One investigation of the two major manufacturers of laparoscopic clip appliers studied the pressures necessary to dislodge each type of clip in vitro and in vivo (2). In detailed measurements on both axial and horizontal displacement, the Ethicon clips held more effectively than the U.S. Surgical clips. Both types had an unusually high rate of distractibility during the in vivo studies (33). A second study quantifying the force necessary to dislodge the newer generation of U.S. Surgical clips, EndoClip II, found them to be much more difficult to dislodge (34). Each study was funded by the manufacturer whose clip was thought to be better, so conclusions must be weighed carefully. The surgeon should be aware that these clips can become dislodged during the course of subsequent dissection if either radial or horizontal traction is applied near or at the clip. Metallic clips, and automated staplers have been described to secure the renal pedicle during laparoscopic nephrectomy and nephroureterectomy (26). On comparing these two modalities to open suture ligation of the renal pedicle in a porcine animal model, all three methods were found to be equally efficacious in preventing arterial leakage at physiological pressures. At superphysiologic pressures (average 1364 mmHg), five of six pigs had leakage from renal arteries secured with an EndoGIA 30™ (26). This multifire vascular stapler cuts between two triple-staggered rows of 2.5-mm staples. Application of three 9-mm titanium clips and suture ligation with a 2-0 silk stitch as well as a 0-silk free tie prevented leakage even at renal artery burst pressures (average, 1821 mmHg). Moran similarly found renal artery branch vessel ligation with three clips transversely placed in opposing directions and linear stapling to be equally

Hemostasis in the closed environment imposed by minimal access surgery is one obstacle blocking progression to more complex intracorporeal techniques. The ability to maintain a clear surgical field allows complex tasks such as suturing to be performed.

TABLE 1 ■ Methods of Laparoscopic Hemostasis Excluding Augmenting Peripheral Clotting Parameters

Mechanical Pressure Clamping Thermal

Radiofrequency electrocautery Monopolar Bipolar Endothermal Argon beam coagulator Lasers Cryoprobes

Radiofrequency energy Microwave energy Chemical

Fibrin glue, calcium impregnated swabs, Endo-Avitene® Suture/ligation Stapling/clipping

There are proponents for loop ligation and for titanium clipping. Urologically, the laparoscopic nephrectomy animal model indicated that clips were associated with more blood loss than autostapling techniques.

aU.S. Surgical Corp., Norwalk, CT.

Current practice recommendations are to use 9-mm titanium clips to secure renal vessels. A total of five clips, three placed proximally and two on the specimen side, placed transversely in opposing directions prior to vessel division is recommended.

The ability of the laparoscopic surgeon to reconstruct the genitourinary tract is fundamentally the same in the closed versus the open abdomen.

TABLE 2 ■ The Five Methods of Tissue Reapproximation

Suturing Stapling Crimping

Thermal welding (laser) Gluing

Note: Each can be applied alone or in combination with the others.

Anastomosis and complex enteric-uroepithelial composite appositions are the rule for urologic reconstruction. A number of synthetic, autograft, and xenograft materials have been sought to further diminish the trauma of urologic reconstruction.

efficacious in a porcine animal model (27). En masse occlusion of the renal pedicle without separating the artery and vein, using a 12 mm vascular stapler has also been examined in animals. One of three animals followed for six months demonstrated an arteriovenous fistula on aortography (26). The true risk of arteriovenous fistula formation from en masse renal pedicle ligation may be even higher given previous studies documenting their formation 5 months to 40 years after surgery (32-34).

Current practice recommendations are to use 9-mm titanium clips to secure renal vessels. A total of five clips, three placed proximally and two on the specimen side, placed transversely in opposing directions prior to vessel division is recommended.

Finally, a case where a partial nephrectomy was performed utilizing a linear cutting stapler has been described (35). Despite the widespread application of clipping and stapling technologies, there still exists a role for the use of suture in the management of the vascular pedicles during laparoscopic surgery. The most tried and true method of hemo-stasis remains the surgical ligature; it is cost effective and almost always readily available.

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