Simple suturing technique

Basic suturing principles

Many varieties of suture material and needles are available to the cutaneous surgeon. The choice of sutures and needles is determined by the location of the lesion, the thickness of the skin in that location, and the amount of tension exerted on the wound. Regardless of the specific suture and needle chosen, the basic techniques of needle holding, needle driving, and knot placement remain the same.

• Needle construction

  • The needle has 3 sections. The point is the sharpest portion and is used to penetrate the tissue. The body represents the mid portion of the needle. The swage is the thickest portion of the needle and the portion to which the suture material is attached.
  • In cutaneous surgery, 2 main types of needles are used: cutting and reverse cutting. Both needles have a triangular body. A cutting needle has a sharp edge on the inner curve of the needle that is directed toward the wound edge. A reverse cutting needle has a sharp edge on the outer curve of the needle that is directed away from the wound edge, which reduces the risk of the suture pulling through the tissue. For this reason, the reverse cutting needle is used more often than the cutting needle in cutaneous surgery (see image below).
    Diagram of a needle.
    
• Suture placement

  • A needle holder is used to grasp the needle at the distal portion of the body, one half to three quarters of the distance from the tip of the needle, depending on the surgeon's preference. The needle holder is tightened by squeezing it until the first ratchet catches. The needle holder should not be tightened excessively because damage to both the needle and the needle holder may result. The needle is held vertically and longitudinally perpendicular to the needle holder (see image below).
    
     
    The needle is placed vertically and longitudinally perpendicular to the needle holder.
    
  • Incorrect placement of the needle in the needle holder may result in a bent needle, difficult penetration of the skin, and/or an undesirable angle of entry into the tissue. The needle holder is held by placing the thumb and the fourth finger into the loops and by placing the index finger on the fulcrum of the needle holder to provide stability (see first image below). Alternatively, the needle holder may be held in the palm to increase dexterity (see second image below).
    The needle holder is held through the loops between the thumb and the fourth finger, and the index finger rests on the fulcrum of the instrument.
    
    The needle holder is held in the palm, allowing greater dexterity.
    
  • The tissue must be stabilized to allow suture placement. Depending on the surgeon's preference, toothed or untoothed forceps or skin hooks may be used to gently grasp the tissue. Excessive trauma to the tissue being sutured should be avoided to reduce the possibility of tissue strangulation and necrosis. Forceps are necessary for grasping the needle as it exits the tissue after a pass. Prior to removing the needle holder, grasping and stabilizing the needle is important. This maneuver decreases the risk of losing the needle in the dermis or subcutaneous fat, and it is especially important if small needles are used in areas such as the back, where large needle bites are necessary for proper tissue approximation.
  • The needle should always penetrate the skin at a 90° angle, which minimizes the size of the entry wound and promotes eversion of the skin edges. The needle should be inserted 1-3 mm from the wound edge, depending on skin thickness. The depth and angle of the suture depends on the particular suturing technique. In general, the 2 sides of the suture should become mirror images, and the needle should also exit the skin perpendicular to the skin surface.
• Knot tying

  • Once the suture is satisfactorily placed, it must be secured with a knot. The instrument tie is used most commonly in cutaneous surgery. The square knot is traditionally used. First, the tip of the needle holder is rotated clockwise around the long end of the suture material for 2 complete turns. The tip of the needle holder is used to grasp the short end of the suture. The short end of the suture is pulled through the loops of the long end by crossing the hands, such that the 2 ends of the suture material are situated on opposite sides of the suture line. The needle holder is rotated counterclockwise once around the long end of the suture. The short end is grasped with the needle holder tip, and the short end is pulled through the loop again.
  • The suture should be tightened sufficiently to approximate the wound edges without constricting the tissue. Sometimes, leaving a small loop of suture after the second throw is helpful. This reserve loop allows the stitch to expand slightly and is helpful in preventing the strangulation of tissue because the tension exerted on the suture increases with increased wound edema. Depending on the surgeon's preference, 1-2 additional throws may be added.
  • Properly squaring successive ties is important. That is, each tie must be laid down perfectly parallel to the previous tie. This procedure is important in preventing the creation of a granny knot, which tends to slip and is inherently weaker than a properly squared knot. When the desired number of throws is completed, the suture material may be cut (if interrupted stitches are used), or the next suture may be placed (see image below).
    
    Knot tying.

Foley catheter insertion (male and female)

Indications
By inserting a Foley catheter, you are gaining access to the bladder and its contents. Thus enabling you to:
 drain bladder contents,
decompress the bladder,
 obtain a specimen,
and introduce a passage into the GU tract.

This will allow you to treat urinary retention, and bladder outlet obstruction.

Urinary output is also a sensitive indicator of volume status and renal perfusion (and thus tissue perfusion also).

In the emergency department, catheters can be used to aid in the diagnosis of GU bleeding.

In some cases, as in urethral stricture or prostatic hypertrophy, insertion will be difficult and early consultation with urology is essential.

Contraindications
Foley catheters are contraindicated in the presence of urethral trauma.
 Urethral injuries may occur in patients with multisystem injuries and pelvic factures, as well as straddle impacts. If this is suspected, one must perform a genital and rectal exam first. If one finds blood at the meatus of the urethra, a scrotal hematoma, a pelvic fracture, or a high riding prostate then a high suspicion of urethral tear is present. One must then perform retrograde urethrography (injecting 20 cc of contrast into the urethra).

Nasogastric tube insertion

Indications
By inserting a nasogastric tube, you are gaining access to the stomach and its contents.
This enables you to:
 drain gastric contents,
 decompress the stomach,
 obtain a specimen of the gastric contents,
 or introduce a passage into the GI tract.

 This will allow you to treat gastric immobility, and bowel obstruction.

 It will also allow for drainage and/or lavage in drug overdosage or poisoning.

 In trauma settings, NG tubes can be used to aid in the prevention of vomiting and aspiration, as well as for assessment of GI bleeding.

 NG tubes can also be used for enteral feeding initially.

Contraindications
Nasogastric tubes are contraindicated in the presence of severe facial trauma
(cribriform plate disruption), due to the possibility of inserting the tube intracranially.
In this instance, an orogastric tube may be inserted.

Cannula and Peripheral IV line insertion

Contraindications

Absolute Contraindications: None

Relative Contraindications:

    Avoid extremities that have massive edema, burns, or injury; in these cases other IV sites need to be accessed.

    Avoid going through an area of cellulitis; the area of infection should not be punctured with a needle because of the risk of inoculating deeper tissue or the bloodstream with bacteria.

    Avoid extremities with an indwelling fistula; it is preferable to place the IV in another extremity because of changes in vascular flow secondary to the fistula.

    An upper extremity on the same side of a mastectomy should be avoided, particularly if an axillary node dissection was carried out, because of concerns of previous lymphatic system damage and adequate lymphatic flow.

    Very short procedures performed on pediatric patients, like placement of ear tubes

    Bleeding diathesis

    Medication administration that will take longer than 6 days (preference is then for a peripherally inserted central catheter)

    Type of fluid to be administered through peripheral IV is too caustic; hypertonic solutions and some therapeutic agents should not be infused in a peripheral IV.

Central line placement

Indications:

• Placement of venous access line when other peripheral sites are unavailable
• Placement of a large-bore venous catheter in an emergent situation to deliver a high flow of fluid or blood products (the flow rate is determined by the caliber and length of the catheter, shorter and greater caliber catheters delivering greater volumes over equivalent amounts of time)
• Central venous pressure measurement
• Administration of sclerosing agents such as chemotherapeutic agents, hyperalimentation fluids, etc.
• As an alternative to repetitive venous cannulations
• For placement of pulmonary wedge catheters
• For placement of trans venous pacemakers
• For performance of hemodialysis or plasmapheresis

Contraindications:

• Infection over the insertion site
• Distortion of landmarks from any reason
• Suspected injury to the superior vena cava (eg., SVC syndrome)
• Coagulopathies including anticoagulation therapy
• Pneumothorax or hemothorax on the contralateral side
• Inability to tolerate pneumothorax on the ipsilateral side
• Uncooperative patients
• Patients unable to tolerate a Trendelenberg position
• Prior injury to that vein (choose the one on the other side)
• Morbid obesity
• Recently discontinued subclavian catheter at the same location
• Planned mastectomy on the side of subclavian insertion
• Patients receiving ventilatory support with high end expiratory pressures (temporarily reduce the pressures)
• Patients with vigorous, ongoing cardiopulmonary resuscitation
• Children less than 2 years (higher complication rates)
• Fracture or suspected fracture of ipsilateral upper ribs or clavicle

Complications, Prevention and Management:

·        Pneumothroax

o       Prevention: Remove patient from ventilator before advancing the needle, choose the right side rather than left, avoid multiple attempts when possible

o       Management: Check postprocedure x-ray, if pneumothorax arrange for thorcostomy depending on the size of the pneumothorax

• Hemothorax - as above
• Bilateral Iatrogenic complications

o       Prevention: If attempted catheterization is unsuccessful, try the ipsilateral internal jugular or subclavicular approach before trying contralateral subclavian catheterization

• Catheter embolization

o       Prevention: Never withdraw a catheter past a needle bevel which might shear off the catheter

o       Management: x-ray the patient and contact specialist who can remove the embolized catheter

• Infection

o       Prevention: Never choose an insertion site that goes through infected tissue; use antimicrobial-impregnated catheters; avoid the use of antibiotic ointments (increase of fungal contamination and antibiotic resistant bacteria)

• Cardiac dysrhythmia

o       Prevention: if available, have someone watch monitor for dysrhythmia while the catheter is advanced (this comes from direct contact of the catheter tip with the myocardium of the right atrium)

o       Management: reposition the catheter; treat dysrhythmia according to ACLS protocols.

• Air embolism

o       Prevention: Maintain a Trendelenberg position, ask the patient to exhale while you are advancing the catheter, maintain a "closed system

o       Management: Place the patient in a left lateral decubitis, head down position to minimize the chances of an air embolism to the brain.

Digital block

Digital nerve blocks are important tools for the emergency medicine clinician. Injuries or infections of the digits are extremely common. Adequate analgesia is essential to properly address the presenting condition and to minimize the patient's discomfort. Digital blocks are useful in many scenarios in which local infiltration of an anesthetic would require several injections into the already painful site of injury. Furthermore, local infiltration around the wound may create increased swelling, making the repair more difficult. Several techniques are available for performing digital blocks.

Indications

Digital blocks are indicated for any minor surgery or procedure of the digits. These include, but are not limited to, the following:

    Large irregular lacerations
    Lacerations involving the nail or the nail bed
    Ingrown nails
    Felon or paronychia
    Trephination of subungual hematoma
    Digit dislocations or fractures

Contraindications

    Compromised digit circulation
    Infected injection site
    Known allergy to anesthetic

Arterial Blood Gas Sampling

ABG sampling provides valuable information on the acid-base balance at a specific point in the course of a patient's illness. It is the only reliable determination of ventilation success as evidenced by CO2 content. It constitutes a more precise measure of successful gas exchange and oxygenation. ABG sampling is the only way of accurately determining the alveolar-arterial oxygen gradient (see the A-a Gradient calculator).

Indications

Indications for ABG sampling include the following:

    Identification of respiratory, metabolic, and mixed acid-base disorders, with or without physiologic compensation, by means of pH ([H+]) and CO2 levels (partial pressure of CO2)

    Measurement of the partial pressures of respiratory gases involved in oxygenation and ventilation

    Monitoring of acid-base status, as in patient with diabetic ketoacidosis (DKA) on insulin infusion; ABG and venous blood gas (VBG) could be obtained simultaneously for comparison, with VBG sampling subsequently used for further monitoring
    Assessment of the response to therapeutic interventions such as mechanical ventilation in a patient with respiratory failure
    Determination of arterial respiratory gases during diagnostic evaluations[2, 3] (eg, assessment of the need for home oxygen therapy in patients with advanced chronic pulmonary disease)
    Quantification of oxyhemoglobin, which, combined with measurement of arterial oxygen tension (PaO2), provides useful information about the oxygen-carrying capacity of the patient
    Quantification of the levels of dyshemoglobins (eg, carboxyhemoglobin and methemoglobin)
    Procurement of a blood sample in an acute emergency setting when venous sampling is not feasible (many blood chemistry tests could be performed from an arterial sample[4] )

Contraindications

Absolute contraindications for ABG sampling include the following:

    An abnormal modified Allen test (see below), in which case consideration should be given to attempting puncture at a different site

    Local infection or distorted anatomy at the potential puncture site (eg, from previous surgical interventions, congenital or acquired malformations, or burns)

    The presence of arteriovenous fistulas or vascular grafts, in which case arterial vascular puncture should not be attempted

    Known or suspected severe peripheral vascular disease of the limb involved

Relative contraindications include the following:

    Severe coagulopathy

    Anticoagulation therapy with warfarin, heparin and derivatives, direct thrombin inhibitors, or factor X inhibitors; aspirin is not a contraindication for arterial vascular sampling in most cases

    Use of thrombolytic agents, such as streptokinase or tissue plasminogen activator