Hemostasis is the term that refers to the typical response of the vessel to injury by activation of the blood clotting mechanism to limit bleeding. It has been an essential goal in any surgery to maintain hemostasis by restricting the blood loss thus reducing the need for blood transfusion and its complications. Hemostasis is more prudent during laparoscopic surgery where the intervention is performed through small incisions using the camera and specialized instruments, as even minor bleeding may affect visualization, the safety and quality of the procedure, and patient outcome.
In laparoscopy, surgeons can attain a bloodless field with various available methods of hemostasis which requires the timely and appropriate use of technology. Having a sound understanding of each of the numerous forms of hemostasis will ensure proper usage and avoid complications. As a general rule, there are two available methods for hemostasis during laparoscopy, namely standard mechanical hemostasis (ligation, suturing, and electrocautery) and adjunct hemostasis (tissue adhesives and sealants) methods [1]. We provide a broad overview of these two available methods during laparoscopic surgical intervention.
Direct pressure is often possibly the first maneuver employed to achieve hemostasis in laparoscopic surgery. Direct application of blunt laparoscopic equipment, e.g., a 5 mm blunt tip atraumatic grasper to a bleeder point, temporarily stops the blood loss through local tamponade [2]. Direct pressure allows the surgeon time to adequately visualize the area of interest and formulate the next course of action for hemostasis. Applying the direct pressure against a gauze wick or sponge at the bleeding point, which is inserted through a 10 mm port can further enhance the effect of this method (Fig. 1).
Fig. 1Using tonsil swab for hemostasis
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With regards to physiology, such maneuver initiates the process of hemostasis through platelet aggregation and fibrin clot formation. Furthermore, it may well be all that is required to halt the bleeding depending on the size of the blood vessels and the patient’s coagulation status [2].
Electrosurgical tools are often the principal instrument for securing hemostasis after local tamponade. This tool delivers an energy source from an electrosurgical unit (ESU) to the tissue causing thermal destruction and consequently hemostasis. The energy can be achieved either by monopolar or bipolar electrocautery [2]. Details of the physics of ESU, its principle and complications are discussed in another chapter.
Monopolar Electrocautery
This form of electrosurgery involves current from an active electrode, predominantly hook, grasping forceps, or scissors that are attached to a monopolar generator, which passes through the patient and returns through a large grounding plate.
Bipolar Electrocautery
In this form of electrosurgery, the active electrode is intermittently opposed to the return electrode (usually in a forceps-type arrangement). The electrical current passes between the electrodes to complete the circuit, and the flow of current beyond the surgical field is minimal. The bipolar application thus minimizes the risk of damage to nearby tissue.
Argon Beam Coagulator
Argon beam coagulator is a monopolar electrocautery instrument that uses an ionized, argon jet to complete the circuit between the active electrode and the target tissue to “blow-off” the surgical field by surface proteins denaturation and shallow eschar formation. It is sufficient for minor capillary bleeding after dissection, especially that involves solid organ parenchyma. It is however unsuitable for control of significant bleeding or larger vessels and complications such as argon gas embolism and pneumothorax have been reported from its injudicious use.
Advanced Bipolar System
The LigaSure™ vessel sealing system (Valleylab, Boulder, CO) utilizes a form of bipolar current that is locally modified through a feedback control mechanism on the ESU. As the resistance of the tissue changes during desiccation, the generator adjusts the pulsed energy accordingly. Therefore, a high current with low voltages energy is used to melt the collagen and elastin thus creating a seal with a simultaneous hemostatic division of tissue. The LigaSure™ device is recommended for vessels sized <6 mm only [1].
Ultrasonic Energy
A piezoelectric harmonic scalpel (Harmonic®, Ethicon US, OH, USA) is a tool that simultaneously excises and coagulates tissue with high-frequency ultrasound. A frequency of 25 kHz induces mechanical vibration at the cellular level resulting in dissection and cavitation as seen in cavitational ultrasonic aspirator (CUSA Technologies, Salt Lake City, UT) [1, 2]. At a higher ultrasound frequency of >55 kHz, this piezoelectric ceramic element expands and contracts rapidly thus generating frictional energy that causes a hidden moving blade to oscillate. This results in mechanical energy that seals blood vessels and transects tissues without passing the current to, or through the patient.
The harmonic scalpel is known to cause less collateral damage, avoid carbonization of the tissue, and reduces local thermal injury. It has been used widely in laparoscopy for tissue dissection and control of local blood vessels. It has two modes of action; lower power causes slower tissue heating and more coagulation effect, while higher power setting causes rapid cutting but is relatively nonhemostatic. However, the use of the harmonic scalpel is limited to vessels of <4 mm in diameter (Fig. 2). Newer generation device may allow sealing of up to <7 mm diameter [1, 2].
Fig. 2Application of endoscopic clip system for ligation of cystic artery and use of ultrasonic energy device for transection of the artery
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Similar to open surgery, tissue approximation by suturing will result in immediate hemostasis if done correctly. Suturing can be achieved either by extracorporeal or intracorporeal methods depending on the surgeon’s preference or experience. Although suturing is the most basic in open surgery, it is the most challenging skill required of a laparoscopic surgeon.
Extracorporeal Suturing
The surgeon creates the knot outside the body using a series of half-hitch knots that are advanced into the abdomen through a port by using a knot pusher. The suture lengths are usually longer than 70 cm. Care must be exercised during extracorporeal suturing as excessive traction during passing and redelivery of the suture may lead to “sawing” of the tissue.
Intracorporeal Suturing
This technique requires skill to manipulate the needle, to pass it from one needle driver to the next, and to execute a series of knots. The required suture length for this type of suturing is usually between 12–17 cm.
Occluding the bleeding vessel by suture ligation is an effective way of hemostasis in surgery; however, as for suturing, it may not be handy in laparoscopic surgery for many.
Simple Ligature
Again both extracorporeal and intracorporeal methods can be used to execute the ligature.
Pretied Suture Loops
Ready-to-use pretied suture loops (Endo-loops) may be particularly useful for surgeons unfamiliar with laparoscopic suturing. Its use however requires the division of a bleeding vessel or vascular pedicle in order to loop the vessel of interest hence its suboptimal choice where the vessels are still intact.
An endoscopic clip is another method preferred by most surgeons to seal a blood vessel. Both 5 and 10 mm reusable clips and appliers, as well as their disposable counterparts, are available. The only difference is that reusable clips are reloaded after each firing which may potentially delay clipping of a targeted vessel.
Titanium Clips
Most mechanical clips using reusable clip applier are made from titanium. However, they tend to slip off during dissection; therefore, multiple applications of at least 2–5 clips seem to be necessary for safe control of vessels (Fig. 2).
Polymer Ligation Clip System (Hem-o-lock™ clips, Weck, USA).
This clip system comprises of a self-sealing, hook-like mechanism that “lock” when applied correctly with fewer tendencies to slip off as compared to titanium clips. It is a safer alternative to control even significantly large vessels such as renal vein or artery as it comes in various sizes from the medium, large, and extra-large.
The preferred method of clip system largely depends on the surgeon and also on the anticipated size of the vessels. Before the clip application, it is crucial to visualize both sides of the clip to ensure adequate tissue uptake and prevent inadvertent clipping of nontarget structure. Ischaemic necrosis, perforation, and laceration of surrounding tissues are common complications resulting from inadequate meticulous dissection before clipping a structure and incorrect clip application.
This device sometimes referred to as vascular endo stapler (Endo-GIA, Covidien, US; Endopath Flex, Ethicon, US) is ideal in situations where mechanical clips are not large enough to seal large caliber vessels [3]. Stapler height of 2.0–2.5 mm can safely occlude major vessels or vascular pedicles as a newer device utilizes three lines of staples for simultaneous vascular sealing and cutting. However, modern endo staplers are bulky instruments that require 12–18 mm access port to work in a limited space and equipped with a rotating or angulating system hence costly [1]. The firing of stapler requires some training beforehand to avoid stapler “malfunction” as the improper technique may cause insufficient sealing of vessel resulting in life-threatening bleeding.
Topical hemostatic agents and tissue sealants or adhesives are available as an adjunct to manage bleeding during open surgery or laparoscopy when conventional hemostatic techniques (mechanical, thermal, and chemical) are inadequate or impractical [1, 4]. Topical hemostats and sealants have become essential tools of laparoscopic surgery due to their ability to reduce bleeding complications. These are especially convenient for diffuse bleeding from the nonanatomic region, bleeding near sensitive structures, e.g., nerve, and bleeding in patients with coagulopathy.
The two main categories of topical hemostatic agents are physical agents, which promote hemostasis using a passive substrate, and biologically active agents, which enhance the coagulation process at the bleeding site [4]. Examples of the commonly used hemostatic agents in laparoscopy are;
Dry physical agents produce a matrix that activates the coagulation cascade and acts as a scaffold for thrombus to form and build up. These agents are easy to use; however, they are less effective if bleeding is brisk.
Oxidized Regenerated Cellulose
Oxidized regenerated cellulose (ORC) is a dry, absorbable sterile mesh (Surgicel™) that is derived from cotton cellulose which can be applied directly to an area of bleeding (Fig. 3). Results are optimal if bleeding is minimal (i.e., oozing). ORC is commonly used to control bleeding at vascular anastomotic sites, the cut surfaces of solid organs (Fig. 3), and retroperitoneal or pelvic surfaces after lymphadenectomy [4]. Apart from mechanical effects, cellulosic acid helps hemostasis by blood protein denaturation. Because ORC is pliable, it can be rolled and passed easily through laparoscopic trocars. A single-layer sheet is fully absorbed in approximately 14 days.
Recently, ORC has been manufactured into a powder form (Surgicel® Powder) that can penetrate the blood to stop bleeding at the source. It comes with a unique endoscopic applicator for use in laparoscopy.
Gelatin Matrix
Gelatin (e.g., Gelfoam, Surgifoam™) is a hydrocolloid made from partial acid hydrolysis of porcine-derived collagen that is whipped into foam and then dried. It is available in sponge or powder form. Gelatin sponge absorbs blood or fluid up to 40 times its weight, and when saturated with blood, it expands up to 200% in its dimensions [4].
The dry sponge is rigid and firm when dry, but became soft and pliable after moistening thus able to be molded into any shape for easy passage through laparoscopic ports. Hemostasis occurs when the sponge is pressed for several minutes at the intended area and left in place. It is completely absorbed after 4–6 weeks.
Hemostasis by application of oxidized regenerated cellulose (Surgicel™) to liver parenchymal surface
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These agents are commonly referred to as tissue adhesives or glues promote tissue sealing and support by reproducing the different phases of coagulation. They are suitable for managing diffuse bleeding from oozing surfaces but not from major vascular bleeding. The lack of adequate adhesion strength enables any forceful bleeder to displace the products away from the bleeding tissue. Some of these agents are;
1.
Topical Thrombin
Topical thrombin that is reconstituted from a lyophilized powder is a bovine-derived thrombin component. It can be applied using a sprayer onto an oozing surface or applied with a needle and syringe directly to a specific area of bleeding [3]. Topical thrombin can also be used in conjunction with a bovine gelatin matrix agent (sponge or granules) that provides the thrombin with an immediate scaffold for clot formation (Floseal™, Surgiflo™).
Recently, human thrombin and recombinant thrombin are available for use and have primarily replaced bovine thrombin.
2.
Fibrin Sealant
Fibrin sealants or glues are typically a mixture of a two-component system; a solution of concentrated fibrinogen and factor XII, and a solution of thrombin and calcium. When the components are mixed immediately before use, a solid fibrin matrix or clot forms [3]. Owing to their liquid nature, they are readily used in laparoscopy which is then applied using a long applicator needle and a dual-lumen adapter.
Fibrin sealant can control bleeding at vascular anastomotic sites. Use of fibrin glue in conjunction with a gelatin sponge (Tisseel™) is useful to control bleeding from superficial cut surfaces but not from severe vascular bleeding. Human-derived fibrin glue (Crosseal™) meanwhile has a shorter operative time but higher complication rate [1].
3.
TachoComb™ or Tachosil™
Made from dry, equine collagen bovine thrombin, bovine aprotinin, and human fibrinogen, this fleece (TachoComb™, NycomedLinz, Austria) works by mimicking the final steps of the human coagulation process [1, 3]. As the fleece comes in contact with blood or body fluids, it immediately activated and forms a patch and hemostasis ensued. It must be applied correctly to prevent premature activation of the patch. Hence, for laparoscopy, the pre-rolled TachoSil™ is delivered by a special clamp. TachoSil™ (human fibrinogen and equine collagen) forms a dense tissue-like sealant at the surface of the parenchymal lesion or defect within 3–5 min, following constant compression and moisturizing with normal saline, and will be replaced by vital tissue. Therefore, it can be applied even when bleeding is absent and in patients with coagulopathy. After proper application, it is possible to subject the sealed surface to further bipolar coagulation, or suturing without jeopardizing the sealant effect. TachoSil™ has an anti-adhesive property that separates the sealant tissues from other structures nearby.
With various types of topical hemostatic agents available, the choice of which to use will depend on the character, amount, and location of bleeding; surgeon preference and cost considerations. Dry matrix agents are less effective when bleeding is brisk; however, fibrin sealant is a more appropriate choice when moderate bleeding is uncontrolled by other measures.
1.
Visualize and identify all structures before division.
2.
Avoid blunt avulsion or stripping of adhesions and fat tissues.
3.
Safely apply energy to the area to be divided.
4.
Preemptive clipping of a structure or dissect generous enough if unsure about its vascularity to allow prompt control if bleeding occurred after division.
1.
Avoid panic situation.
2.
Avoid random application of energy or clips towards the presumed bleeding point.
3.
Visually identify the bleeding without taking away necessary retraction.
4.
Suction the area with a suitable suction device and avoid too much irrigation. If possible, insert a gauze through a 10 mm port site to achieve temporary tamponade (Fig. 1).
5.
Apply gentle pressure with an atraumatic grasper to the bleeding point where identified.
6.
If the bleeding does not stop with direct identification and pressure, convert to an open procedure.
7.
If the bleeding stops with the above measures, ensure that there are enough port sites for adequate instrumentation. Insert extra ports for better visualization and retraction, and possibly for optimal triangulation if suturing is required.
8.
Place a mechanical clip on both sides of the area being grasped (Fig. 2).
9.
Irrigate and evaluate.
10.
If necessary, apply electrical and ultrasonic energy judiciously.
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