Means of Promoting Wound Hemostasis
Wound hemostasis can be obtained in five ways. The first is by assisting natural hemostatic mechanisms. This is usually accomplished by either using a fabric sponge to place pressure on bleeding vessels or placing a hemostat on a vessel. Both methods cause stasis of blood in vessels which promotes coagulation. A few small vessels generally require pressure for only 20 to 30 seconds, whereas larger vessels require 5 to 10 minutes of continuous pressure. The surgeon assistants should dab rather than wipe the wound with sponges to remove extra vasated blood. Wiping is more likely to reopen vessels that are already plugged by clotted blood.
A’second means of obtaining hemostasis is by the use of heat to cause the ends of cut vessels to fuse closed tthermal coagulation). Heat is usually applied through an electrical current that the surgeon concentrates on the
bleeding vessel by holding the vessel with a metal instrument, such as a hemostat, or by touching the vessel directly witfi an electrocauteryztjp, Three conditions should be created for proper use of thermal coagulation.
First, the patient must be grounded, to allow the current to enter the body. Second, the cautery tip and any metal instrument the cautery tip contacts cannot touch the patient at any point other than the site of the bleeding
vessel. -Otherwise the current may follow an undesirable path and create a burn. The third necessity for thermal coagulation is the removal of any blood or fluid that has accumulated around the vessel to be cauterized. Fluid acts as an energy sump and thus prevents a sufficient amount
of heat from reaching the vessel to cause closure.
The third means of providing surgical hemostasis is by suture ligation. If a sizable vessel is already severed, each end is grasped with a hemostat. The surgeon then ties a nonabsorbable suture around the vessel. If a vessel can be dissected free of surrounding connective tissue before it is cut, two hemostats can be placed on the vessel, with enough .space left between them to cut the vessel. Once the vessel is severed, sutures are tied around each end and the hemostats removed.
The fourth means of gaining hemostasis is by placement, of a pressure dressing over the wound. This creates pressure on the small vessels that were cut, promoting coagula
tion. Care must be taken not to apply so much pressure as to compromise wound vascularity. Most bleeding from dentoalveolar surgery can be controlled by this means. The fifth method of promoting hemostasis is by placing vasoconstrictive substances, such as epinephrine, in’
the wound or by applying procoagulants, such as commercial thrombin or collagen, on the wound. Epinephrine serves as a vasoconstrictor most effectively when placed in the site of desired vasoconstriction at lease 7
minutes before surgery begins .