SAJA ALDULAIJAN

PERCUTANEOUS TRACHEOSTOMY

Tracheostomy is a common surgical procedure performed on critically ill intensive care patients.

procedures are rapidly transforming many areas of surgical practice. Percutaneous tracheostomy, a minimally invasive alternative to conventional tracheostomy.

Two new methods suitable for elective percutaneous tracheostomy at the bedside have been introduced based on the Seldinger technique.

The Ciaglia method, developed by Ciaglia et al in 1985, uses graded dilators and is currently the most popular method.

Another technique, described by Griggs et al in 1990, is a one-stage dilation technique using a modified Howard-Kelly forceps as the tracheal dilator.

Percutaneous tracheostomy can be performed by an anaesthetist at the bedside in a controlled setting (ICU) with the assistance of nursing personnel without the need to transfer the critically ill patient to the operating theatre.

INDICATIONS FOR TRACHEOSTOMY

1. Facilitate weaning from positive pressure ventilation and sedation

2. Bypass an obstruction of the upper respiratory tract.

3. Prevent aspiration from the pharynx or gastrointestinal tract.

4. Facilitate removal of secretion by aspiration.5. Facilitate long-term airway management

Why percutaneous tracheostomy not open surgical tracheostomy

It is a relatively simple technique suitable for trained staff in the critical care setting.

It does not require an operating theatre and the procedure is usually performed under local anaesthetic, sedation and neuromuscular blockade as appropriate.

Forms a stoma between tracheal rings, resulting in reduced blood loss as there is usually no disruption of blood vessels. Moreover, the tracheostomy tube is fitted snugly in the stoma thereby minimising any tendency to bleeding after the procedure.

Infection rates for percutaneous tracheostomy range from 0 to 3.3%, whereas those for open tracheostomy have been reported to be as high as 36%.

Stenosis rates for percutaneous tracheostomy range from 0 to 9%. The reported incidence of late complications resulting from open tracheostomy such as tracheal stenosis, tracheomalacia, fistula and scarring varies widely.

Small and neat stoma of dilatational tracheostomy generally results in a more cosmetic scar.

Conditions in which surgical tracheostomy may be safer than percutaneous tracheostomy:

Emergency tracheostomy tube placementDifficult to palpate the anatomical landmarks:

very obese patients short or bull neck enlarged thyroid nonpalpable cricoid cartilage gross deviation of trachea

Infection at or near the intended site for tracheostomy. In paediatric age group (controversial). Children have

a more compliant trachea than adults leading to a tendency to collapse when pressure is exerted with dilators.

Previous neck surgery may distort the anatomy.

In unstable cervical spine fracture. Required PEEP > 15 cm H 2 O, as

oxygenation may becompromised during the procedure.

Malignancy at the site of tracheostomy.Uncontrolled coagulopathy, considered as a

relative contraindication

DESCRIPTION OF TECHNIQUES

Equipment

The percutaneous trachesotomy set illustrated is manufactured by Cook Critical Care, although other sets are available. It consists of a Seldinger type needle & wire, over which a guide and then series of dilators are passed. In addition to the equipment given, one also needs :

1. Sterile field & cleaning fluid 2. Lubricating jelly (plenty of) 3. Local anaesthetic with adrenaline 4. Tracheal dilator 5. Fibreoptic laryngoscope/bronchoscope 6. Catheter mount to accept scope 7. Intravenous anaesthesia

Airway Management

Although inhalation anaesthesia is possible, a total intravenous technique provides much smoother anaesthesia and better conditions for performing the bronchoscopy and tracheostomy. Full monitoring is instituted, and ventilatory parameters altered during the bronchoscopy to maintain adequate oxygenation and end-tidal CO2 levels.

Following induction of anaesthesia, the patient is prepped and draped. The bronchoscope is passed through a tracheal tube and the anatomy of the airway visualised. The aim of the fibreoptic scope is to ensure correct initial placement of the introducer needle, in the midline and through the second or third tracheal rings. Subsequent to this, it will monitor dilation of the trachea, and ensure the introducer is not remains in the trachea

Although not necessary for the procedure, information from bronchoscopy is very useful and it should always be used when learning the technique

Landmarks

The patient is positioned with the neck extended, with a intravenous fluid bag between the shoulder blades and the head in a head ring. This brings as much of the trachea as possible into the neck. The important landmarks have been drawn on the patient in the picture at left.

The larynx (hatched) and cricoid cartilage with the intervening cricothyroid membrane are identified. The suprasternal notch has also been marked. From the cricoid, moving caudally, the tracheal rings are identified. The tracheostomy should ideally pass between the second and third tracheal rings, although a space one higher or lower may be employed. Placing the airway higher, next to the cricoid can cause tracheal erosion and long term problems.

Seldinger Method

Local anaesthetic with adrenaline is infiltrated subcutaneously, and a 1cm incision made horizontally with a scalpel. Keeping in the midline at all times, the introducer needle and syringe are advanced, at 45 degrees to the skin, until air is aspirated from the trachea.

The guidewire is passed through the needle, then the small dilator (green) is passed. this is then removed and the white introducer passed into the trachea. The guidewire is removed. Now only the white introducer is left in the trachea.

Dilation

Over this the tracheal dilators (blue) are passed in order, gradually dilating the incision to accommodate the appropriately sized tracheostomy tube. Plenty of lubricating jelly is applied to each dilator, and they are passed down the tract with a twisting motion. Only moderate downward force is applied. If the dilator does not pass easily, return to the previous smaller dilator and ensure it passes freely and easily. Often it is the skin that impedes progress, and the incision has to be slightly widened with the scalpel

Each size of tracheostomy tube has a corresponding dilator size (see the manufacturers instructions), and this should pass freely and easily into the trachea before attempting to insert the tracheostomy tube.

Tube placement

Once the tracheostomy will easily accept the final dilator, the tracheostomy tube (cuff already checked) is loaded onto the dilator one size lower. The tracheal tube is wathdrawn, under direct vision, into the larynx, and the tracheostomy tube is passed over the introducer into the trachea. Once again, undue force should not be necessary. Use plenty of jelly and if required return to the previous dilator.

The use of the tracheal dilator instruments is rarely necessary, and may be hazardous. However, if the introducer is inadvertently pulled out of the trachea, or some other mishap occurs, they may be useful in relocating the tract for replacement.

Finished

With the tracheostomy tube in place, the tracheal tube is removed and the ventilator is connected to the tracheostomy. The chest is auscultated for adequate ventilation and the ventilator checked for appropriate tidal volumes and airway pressures. The tube is secured with tapes or ties.

COMPLICATIONS OF INSERTION

During the procedure, the patient may develop hypoxia due to failure of ventilation. Furthermore, ventilation of the patient may also be difficult if the cuff of the endotracheal tube is inadvertently punctured. If any difficulties are encountered on insertion of the tracheostomy tube, the existing endotracheal tube should be advanced beyond the incision in the trachea and ventilation recommenced until the patient is stable enough to resume the procedure.

The patient may develop pneumothorax, pneumomediastinum or creation of a false passage and subcutaneous emphysema due to the placement of the tracheostomy tube in the paratracheal space.

Damage or injury to the posterior tracheal wall may lead to tracheo-oesophageal fistula.

Major bleeding is unusual. Minor bleeding can usually be controlled by pressure or occasionally a suture. Haemorrhage into the airway is potentially dangerous as it may result in a blood clot obstructing the airway.

Needle puncture on the lateral wall of trachea may subsequently lead to stenosis. 21

Dislodgement of the tracheostomy tube soon after the procedure may be hazardous as the entry to the trachea is small and deep, hence replacement of the tube may be impossible. The percutaneous tracheostomy tube should not be pushed blindly back in but replaced after proper dilation of the track following orotracheal reintubation.

Secondary haemorrhage may occur either from infection or erosion of vessels.