Dieresis: What is it? Stages in Surgery, Surgical Instruments, General Principles and Types of Incisions

This tissue incision is made using sharp instruments.

The umlaut are all the instrumental practices that are performed in a surgical intervention to open and forge an access path between the tissues, which are underlying the area or tissue to be addressed.

In a surgical intervention there are three steps of basic surgical techniques such as: umlaut, hemostasis and synthesis.

In surgical practice there are two essential elements that the surgeon must take into account: extensive knowledge of human anatomy, because all interventions require a detailed description of the organ in which the surgery is to be performed and of the region adjacent to it. organ.

On the other hand, when a surgical intervention is carried out, the acts must be carried out in a systematic way, that is to say; They must keep an order, to make the cuts, separate, extirpate, repair those tissues and organs, so that these actions are as least invasive as possible and avoid serious repercussions on their components or structures.

These serious repercussions can be: altering the anatomy, tissue damage, wound infections, even the unnecessary loss of an organ.

Stages in surgery

In the times in surgery, the moments in which the patient is treated are described and are divided into: preoperative, intraoperative and postoperative.

The phases into which the intraoperative time is divided are five, as stated below:

Dieresis, cut or incision: in this phase a pathway is created to access the tissues, to excise them or to separate them.

These tissues can be: normal (such as skin, subcutaneous tissue, fasciae, muscles, among others), or tissues united in an abnormal way (such as fibrosis, scars, adhesions, among others).

It is the first step, after the preoperative care and the mandatory asepsis and antisepsis measures are carried out. This cut must comply with a defined methodology that can guarantee access control and integrity of the tissues that are sectioned.

The access route achieved with the incision should be the ideal one according to the site and the procedure to be performed. For this there are a variety of specific surgical instruments to perform each incision.

Hemostasis: these are all technical procedures used to control bleeding that occurs during surgery. The immediate response to tissue section incisions is bleeding of the involved capillaries, veins, and arteries.

The ways to contain the hemorrhages that are used range from a simple digital compression or with the help of compresses in the sectioned tissue. This compression lasts for a few minutes, until it is stopped by the action of a vasospasm and by the formation of a clot in the hemorrhage.

The compression procedure is effective when the vessel that has been sectioned has a small caliber.

In the case of more important hemorrhages, another type of hemostasis should be used. The structure that is bleeding is usually clamped with forcipress forceps, Kocher-Halsted type, Bertola type, among others.

Then the conclusive hemostasis is performed, which is performed by ligating the pressed pedicle, and then removing the clamp. Another procedure used is electrocoagulation with the help of an electro-scalpel.

Exposure (separation, aspiration, traction): in this phase, the organ or tissue is separated, retracted and exposed. This phase is carried out after performing a correct hemostasis.

Surgical instruments such as forceps and retractors are used for tissue separation maneuvers.

This separation procedure can be classified as active (if it is the first assistant who performs the separation with an instrument, adapting it to the surgeon’s requirements) or passive (if the instrument is fixed and there is no need to move it frequently).

Aspiration of the blood remains from the tissue incision is necessary in order to obtain a clearer visual field.

Dissection: this consists in dividing or separating the structures, freeing them from the connective tissue that surrounds them in order to achieve a minimum exposure to have optimal access to the section to be intervened.

This dissection can be with blunt, blunt or sharp instruments such as scissors or a scalpel.

Synthesis of tissues or suture: this is the surgical time whose objective is to join the edges of the wound that were previously incised. For this, sutures are used and depending on the place, resorbable materials or not, single or double stitches, continuous or roundtrip, will be used.

Each one can be performed alternately, the incision is made and hemostasis is made, it can even be continued with another incision for which an exposure of the adjacent anatomical planes is made, and thus, the exposure and dissection during the intervention is continued. , until culminating with the synthesis of the tissues.

Surgical instruments for umlauts

In the procedure to perform a surgical intervention, adequate instruments are required for the execution, such as scalpels and scissors, hemostatic forceps, separators, aspirators, traction instruments, needle holders and suture materials, among others.

Instruments such as:


The scalpel has a handle numbered according to its size numbered from 3 to 9, the most used being numbers 3 and 4.

The scalpel uses blades numbered from 10 to 24.

To use the number 3 handle, leaves from number 13 to number 18 are normally recommended. For the number 4 handle, leaves from number 22 onwards are recommended.

To make the cut there are also techniques, to hold the scalpel it must be placed between the thumb and the middle finger, placing the index finger on the spine of the blade.

The pressure to make the cut must be uniform and very discreet on the skin, using the rounded area of ​​the blade, and never with the tip of the scalpel.

The incision should be deepened by planes and hemostasis should be performed frequently.

It is handled with three points of support: the scalpel socket as a violin bow, for superficial and extensive cuts, the scalpel socket as a table knife, for regular and deep cuts and the scalpel socket as a pencil, for small cuts.

The cut should be made from the furthest to the closest point and the incision started at a 90 ° angle, always placing the scalpel in a position that is perpendicular to the surface or plane of the skin.

To carry out the displacement, it must be held at an angle of 45º, while it is moving through the tissue, and is thus maintained millimeters prior to the completion of the umlaut.

And when the cut is finished, the scalpel is repositioned at the 90º anterior angle.


Scissors are instruments used to perform tissue sections starting from the aponeurotic plane until reaching depth.

Scissors are used to section tissues, to reveal the tissue planes and for muscle and fat tissues.

It should not be used on the toughest tissues or where an exact cut is possible.

The scissors blades will vary according to their objective, angled, straight (they offer a better mechanical advantage when sectioning the most resistant tissues) and curved (these offer better handling and visibility).

The most commonly used scissors are:

  • Mayo scissors, used for fasciae, tendons. They are strong and multipurpose. The shape of these scissors are partially straight or curved and the tips are blunt or blunt-sharp.
  • Metzenbaum scissors, used for fine tissues, to dissect planes and to open ducts or viscera. The relationship between the handle and the leaves is 2: 1 or 3: 1.
  • The Sims Scissors – Used on firm fabrics. They have a shorter cutting branch, are straight or curved and with blunt tips.
  • The Iris scissors: these scissors are small, with sharp and fine tips, they are generally used in ophthalmological interventions.
  • Littauer scissors for removing sutures. These have a concavity in one of their leaves that prevent the suture from rising excessively during removal.
  • Potts scissors are used in cardiovascular surgeries. They are straight or curved, and special for very delicate planes such as veins and arteries.

Electrosurgical unit

The electrosurgical unit is an electronic device that is capable of using electrical energy and converting it into heat energy in order to cut and coagulate soft tissue.

Electric currents develop frequencies that oscillate around 200,000Hz, since these do not interfere with nervous processes.

  • They are used to perform the umlaut and for hemostasis of the bleeding vessels at the same time.
  • Prevents neoplastic cells from entering the bloodstream.
  • Healing is slow.
  • It is contraindicated when there are a large number of vessels and nerves.


Dermatomes are surgical equipment used to cut fragments in the skin predestined for skin grafts.

Grooved probe

It is used for the delicate separation of tissues. It is indicated as a guide in the incision of cavities, especially of the abdomen. This probe prevents internal injuries and facilitates drainage of wounds.

There are also instruments incisions in hard tissue (bone incision): such as the shear, which is an articulated instrument that is used to make incisions, reduce bones or resect cartilaginous surfaces.

General principles of the Dieresis

General rules or principles should be observed before performing an umlaut such as:

  • The incision should be made flat to plane.
  • The incision should be perpendicular to the plane of the tissues.
  • The incisions should preferably be rectilinear.
  • Funnels should be avoided.
  • The size must be appropriate and the direction appropriate.
  • The lines of tension of the skin should be respected as much as possible.

Types of incisions

Incisions can be classified according to:

The axis of the body

  • Longitudinal and vertical incisions.
  • Transverse and horizontal incisions.
  • Oblique incisions.
  • Compound incisions.

The shape

  • Straight incisions.
  • Curved incisions.
  • Mixed incisions.
  • Spindle incisions.
  • Semicircular or arcuate incisions with an “L” or “J” shape.

Depth in:

  • Superficial incisions: These affect the skin, the subcutaneous cellular tissue, and sometimes the fasciae, such as the incisions for thydeidectomies, tracheostomies, or for hernioplasties.
  • Deep incisions: are those that penetrate the serous cavity such as the abdominal cavity, the space in a joint or affect significant muscle groups, such as: a thoracotomy incision, arthrotomy or those practiced in compound fractures, laparoscopies ( which are small incisions where a cavity is penetrated).
  • Open incisions: used when there is contamination in the wound to promote drainage and reduce infections. They are generally used in wounds contaminated by gastric or gallbladder intestinal contents.
  • Closed incisions: they are closed with or without the cannulation of catheters or drains.
  • Middle incisions: these are the so-called supraumbilical or infraumbilical incisions, depending on whether they are located below or above the umbilical scar.

Specific incisions:

  • Rocky-Davis and Mc Burney performed in the appendectomy.
  • Pfannenstiel runs in gynecological surgeries.
  • Lumbotomy to address the retroperitoneum.
  • Kocher which is performed frequently in the bile ducts, the liver.
  • Pribram is practiced to approach the spleen.

The anatomical region

  • The face: semilunar or circular.
  • Neck: transversal, semicircular and longitudinal.
  • Abdomen: in the landmarks.
  • At dawn or the white line.
  • In the xiphoid appendix.
  • On the left and right costal ridges.
  • To the right and left of the anterior superior iliac spine.
  • In the pubis.
  • To the right and left of the inguinal lines.