Hemostasis in surgery complete Techniques of hemostasis used during surgical procedures

Complete methods of hemostasis in surgery and the importance of hemostasis during surgical procedures how hemostasis affect the anesthesia and surgery time and how much it is important for patient life

1. Hemostasis

2. Hemostasis Hemostasis , the arrest of a flow of blood or hemorrhage, is essential to successful wound management. The mechanism is coagulation , or the formation of a blood clot. The clotting of blood takes place in several stages by enzyme reaction . Hemostasis is also a necessary component of good surgical technique. Pooling of blood and serum in the wound in the postsurgical period can increase the risk of infection.

3. Uncontrolled oozing or insecure hemostasis can lead to a hematoma. This is a collection of blood that may need to be surgically removed , especially if the clot impinges on regional nerves and vessels.

4. Bleeding During a Surgical Procedure Two types of bleeding occur during surgical procedures: Pulsating arterial bleeding and venous oozing from denuded or cut surfaces. Although the need to control gross bleeding is obvious, insidious but continuous loss of blood from small veins and capillaries can become significant if oozing is uncontrolled. Complete hemostasis , gentle tissue handling, elimination of dead space , precise wound closure, and a protective wound dressing are essential to minimize trauma to tissue and to enhance healing.

5. Incomplete hemostasis may cause the formation of a hematoma. A hematoma is a collection of extravasated blood in a body cavity, space , or tissue caused by uncontrolled bleeding or oozing. It may be painful and firm to the touch. Some hematomas require evacuation to prevent infection; others reabsorb with time.

6. METHODS OF HEMOSTASIS Numerous agents, devices, and sophisticated pieces of equipment are used to achieve hemostasis and wound closure. These various methods can be classified as chemical, mechanical, or thermal. During surgery, many techniques are used to control bleeding and prevent uncontrolled hemorrhage that would overwhelm the body’s compensatory mechanisms. These techniques include: • Clamping and ligating the bleeding vessel • Sutures that bring tissue edges in close approximation and promote coagulation

7. • Use of electrosurgery to seal a vessel • Use of hemostatic agents , which promote coagulation when directly applied to the bleeding tissue. Blood replacement is a separate process. This may be performed using a blood product during transfusion or by autotransfusion when the patient’s own blood is returned to the body during surgery.

8. Chemical Methods of Hemostasis Chemical forms of topical hemostasis interact with blood to form a clot. Some materials reabsorb during the healing process. Hemostatic materials should not be packed into closed spaces, as in the spinal canal, where they might swell and cause pressure on nerves or other tissues. The material can be applied in confined areas until hemostasis is achieved but removed before closure.

9. Absorbable Gelatn : Absorbable gelatin is a dry sponge or film material derived from porcine tissue. When applied to tissue , it absorbs blood quickly and enhances clot formation. The clot is the result of mechanical rather than chemical action of the material.

10. Absorbable gelatin is most commonly supplied under the proprietary names Gelfoam , Gelfilm , and Surgifoam . These are available in squares, which are cut to size as needed. The usual size used during surgery is 1/4 to 1inch square or rectangular pieces. Absorbable hemostatic agents are not left in place over neural or bone tissue, because tissue injury can result.

11. The scrubbed surgical technologist prepares gelatin sponge on the surgical field. If thrombin is used as a soaking agent for gelatin, the circulator dispenses injectable saline diluent (liquid ) and dry thrombin powder mix to the scrubbed technologist , using aseptic technique. The liquid drug is immediately labeled and used during the case to soak hemostatic gelatin. Gelatin sponge is dispensed in 2- or 3-inch squares for cutting into smaller patches as requested by the surgeon. The pieces are placed in liquid topical thrombin or isotonic saline, or they may be used in dry form.

12. After soaking, gelatin should swell and become soft. If this does not occur, the pieces can be removed from solution and compressed to remove the air. They then are returned to the solution and kept there until use. The technologist can dispense the sponge pieces to the surgeon in a small basin. All gelatin sponge squares are removed from the surgical wound after use. The technologist should collect these and remove them from the sterile field so they do not fall back into the wound.

13. OXIDIZED CELLULOSE: Oxidized cellulose is available in mesh and powder form. It is always applied to tissue in dry form. On contact with blood, it rapidly forms a clot, which is absorbed by the body during the healing process. Oxidized cellulose is manufactured as Surgicel .

14. It must be kept dry until it is used on tissue. If allowed to become wet, it is difficult to handle and loses its shape . It is available in small strips or squares, which may need to be cut with suture scissors. The pieces can then be dispensed to the surgeon in a small basin or container. Any discarded material should be cleared from the surgical site so that it does not enter (or reenter) the wound accidentally.

15. COLLAGEN ABSORBABLE HEMOSTAT: Collagen absorbable hemostat is manufactured from bovine collagen and supplied in dry form as powder, sheets, and sponges. A vitene is approved for use in all surgery and is also supplied in preloaded applicators for endoscopic use. In powder form, it is applied directly to capillary surfaces. The strips may be wrapped around the anastomosis connecting two vessels or hollow structures to form a hemostatic seal. This product is not approved for all surgical tissue. Preparation and use of collagen absorbable hemostat is the same as for oxidized cellulose. It must be kept dry before use.

16. BONE HEMOSTAT: Hemostasis in bone is achieved by applying a waxy substance, commonly called bone wax , into the surface of a bleeding bone. This material, traditionally made from a combination of beeswax and other additives, has been replaced by more biocompatible agents. The current formulation of bone putty is derived from ethylene oxide and propylene oxide ( Ostene ). Bone hemostatic materials must be warmed slightly before use. This is done by kneading small pieces between the gloved fingers. They are dispensed by mounting them on the edge of a small basin or container that can be placed on the sterile field.

17. Flowable Hemostats and Adhesives: Flowable hemostats are composed of porcine or bovine gelatin. They have a viscous quality (approximately the same as honey) and are used in areas that are difficult to access. Some products such as FloSeal (Baxter) and Surgiflow (Johnson & Johnson) also contain pooled human thrombin.

18. Fibrin Sealants: Fibrin sealants are applied to the surface of tissues to bind them together or to prevent air or blood leakage. A few sealants such as natural fibrin have been marketed for some time. Newer combination products and synthetic polymers are now formulated for use as sealants .

19. Uses of sealants : In surgery of the respiratory system, they are used to close air leaks in on lung surfaces and to close bronchial tubes following anastomosis. Hemostatic sealant is used on liver and spleen surfaces that cannot be sutured easily. In vascular surgery, sealants or coagulants are used to bind together vessels in conjunction with sutures that connect blood vessels together (anastomosis).

20. Other uses under experimentation are for use in the esophagus for bleeding esophageal varices, and in endoscopic surgery for hemostasis . Collagen-based adhesives are used for sealing anastomosies in vascular surgery and dura mater leaks.

21. Mechanical Methods of Hemostasis Tourniquets: A tourniquet is a device used to provide hemostasis by constricting the flow of blood in an extremity. It is frequently used on the proximal aspect of an extremity to keep the distal surgical site free of blood. A bloodless field makes dissection easier and less traumatic to tissues and reduces surgical time. Bleeding must be controlled before pressure is released.

22. Precautions for tourniquet application and use are observed. A tourniquet should not be used when circulation in an extremity is impaired or when an arteriovenous access fistula for dialysis is present. A tourniquet can cause tissue, nerve, and vascular injury. Paralysis may result from excessive pressure on nerves. Prolonged ischemia can cause loss of innervation and circulation in the extremity. Tourniquet time should be kept to a minimum

23. Metabolic changes may be irreversible after 1 to 1 ½ hours of tourniquet ischemia. Consideration for latex sensitivity may be an issue for some devices used as tourniquets. Rubber materials should be latex-free if the patient is sensitive to latex products. A tourniquet is dangerous to apply, to leave on, and to remove. A tourniquet may be applied by the surgeon, first assistant, or the circulating nurse on the surgeon’s orders.

24. PNEUMATIC TOURNIQUET: The pneumatic tourniquetis used in limb surgery to create a bloodless surgical site. The tourniquet cuff is a nonlatex air bladder encased in a nylon cuff, much like a blood pressure cuff. Tourniquet cuffs are manufactured in a variety of sizes and widths. Before the tourniquet is placed on the limb, the area where the tourniquet is to be wrapped is padded with flat cotton bandaging material ( Webril or Soft Roll ) that conforms to the shape of the leg or arm as it is wrapped. The tourniquet is then applied over the cotton material (but not yet inflated).

25. To produce a bloodless surgical site, a flexible latex bandage ( Esmarch bandage) is wrapped sequentially around the limb from distal to proximal up to the level of the tourniquet. This exsanguinates the limb, pushing the blood proximally away from the surgical site. The pneumatic tourniquet is inflated with the Esmarch bandage in place. This prevents blood from flowing back into the vessels. Once the tourniquet reaches the designated pressure, the Esmarch bandage is removed. Misuse of a pneumatic tourniquet is associated with tissue necrosis and vascular and nerve damage.

26. Tourniquets are applied and managed only by trained personnel, who observe the following safety precautions to prevent injury to the patient : When the pneumatic tourniquet is inflated, the period from cuff inflation to deflation is called tourniquet time and is measured precisely. Both inflation and deflation times are documented in the patient’s intraoperative chart.

27. The tourniquet may remain inflated for up to 1 hour on an upper extremity and 1.5 to 2 hours on a lower extremity. After that period, the patient is at risk for nerve and vascular damage and tissue necrosis related to ischemia. For an adult patient, the tourniquet pressure must not exceed 50 to 75mm Hg above the patient’s systolic blood pressure for an upper extremity or 100 to 150mm Hg above the systolic pressure for a lower extremity. For a pediatric patient, the upper limit is 100mm Hg above the patient’s systolic pressure.

28. Strict policies regarding the use of tourniquets are enforce in all facilities. Prep solutions and moisture must be prevented from seeping under the tourniquet cuff, because this can cause burns. The pressure gauge must be tested before the cuff is inflated. If surgery continues beyond the recommended inflation time , the tourniquet is deflated for 10 minutes and then reinflated . As soon as it is deflated, the field will fill with blood , and hemostasis must be maintained.

29. The surgical technologist should always roll the Esmarch bandage after it is removed, because it may be needed again during the surgical procedure. The nurse circulator assesses the site for the tourniquet before it is applied. The site is assessed a second time and charted when the tourniquet is removed.

30. Pressure Dressings: Pressure on the wound in the immediate postoperative period can minimize the accumulation of intercellular fluid and decrease bleeding by eliminating dead space. Pressure dressings are used on some extensive wounds to decrease edema and potential hematoma or seroma formation. They may be used as an adjunct to wound drainage to distribute pressure evenly over the wound.

31. Packing: Packing is used with or without pressure to achieve hemostasis and to eliminate dead space in an area where mucosal tissues need support, such as the vagina, rectum, or nose. Packing impregnated with an antiseptic agent, such as iodoform gauze, used to ensure closure of an incision from the wound base toward the outside, as in a large abscess cavity. It is usually removed in 24 to 48 hours. The intraoperative record and patient’s chart should reflect the type , amount, and location of packing.

32. Hemostatic Clamps: Clamps for occluding vessels are used to compress blood vessels and to grasp or hold a small amount of tissue. Ligating Clips: When placed on a blood vessel and pinched shut , clips occlude the lumen and stop the bleeding from the vessel. Metallic clips, such as stainless steel or titanium clips, are small pieces of thin serrated wire that are bent in the center to an oblique angle. Absorbable polymer clips are similar in configuration. Clips are most frequently used on large vessels or those in anatomic locations difficult to ligate by other means. A specific forceps is required for the application of each type available