Formal consent / assent may be appropriate for some procedures, such as tracheostomy, while consent / assent may be implied for minor or life-saving procedures. In any event, always explain to patients, even if apparently ‘unconscious’, what you intend to do and keep relatives informed. Document your intentions, and what has been said / agreed. (See Consent to treatment, p. 29.)

Paralysed and sedated patients in ICU may still feel pain from invasive procedures. Use local anaesthetic for all potentially painful procedures.

Contamination with blood or other body fluids imposes significant risk to staff from blood-borne infection, particularly hepatitis and HIV infection. Universal precautions should be adopted for all invasive procedures. These are intended to prevent the spread of infection, to protect you, your patients and colleagues. It is not always possible to know who has an infection; universal infection control precautions apply to everybody, all of the time:

Wash your hands thoroughly.

Cuts or grazes on the hands or forearms should be covered with a waterproof dressing while at work. Seek medical advice about any septic or weeping areas.

Single-use gloves should be worn for direct contact with blood or body fluid, broken skin or mucous membranes.

Full face visors should be worn to protect against blood or body fluids that may potentially splash the face / eyes.

Gowns or plastic aprons protect clothing from contamination.

Place all sharps directly into a sharps bin; do not manually resheath or break needles. Do not overfill sharps bins, and ensure that the bin is securely fastened before disposal.

Clinical waste should be discarded into colour-coded bags for incineration.

Blood or body fluid spills should be disinfected immediately according to local policies.

Always follow guidelines and safety information that apply to your department. If you need further information, talk in the first place to a senior member of nursing staff. Where necessary, further advice can be obtained from specialists in microbiology, infection control, occupational health, COSHH (Control of Substances Hazardous to Health), health & safety, etc.

ICU patients are generally severely debilitated and at increased risk of infection; therefore, when performing procedures, no matter how minor, good infection control procedures are important. For all invasive procedures strict aseptic technique is required:

Collect all necessary equipment before starting.

Ensure assistance is available to open packs, etc.

Wash hands with disinfectant (generally chlorhexidine or iodine).

Dry hands on towel provided in gown pack.

Put on gown.

Put on gloves using closed technique.

Prepare the equipment on the trolley.

Prepare the patient by washing with 2% chlorhexidine solution (see Epic 2: National Evidence-Based Guidelines for Preventing Healthcare-Associated Infections in NHS Hospitals in England. http://www.neli.org.uk/IntegratedCRD.nsf).

Place sterile towels around the proposed site to make a sterile field.

Remember to keep hands up to avoid contamination.

These are relative. Exercise caution in arteriopaths and do not recannulate an artery where previous vascular compromise has occurred. Where possible avoid areas of local sepsis and trauma, limbs with dialysis fistulae and end arteries such as the brachial artery.

Decide which artery to cannulate. The radial artery of the non-dominant hand is usually preferred in the first instance. Alternatives include the ulnar, dorsalis pedis and posterior tibial arteries. It is pointless, however, to persist with attempts at peripheral arterial cannulation in patients who are hypotensive and ‘shut down’. The femoral and brachial arteries are useful during resuscitation of profoundly shocked patients. Ultrasound guidance is potentially useful at all sites to aid arterial cannulation, particularly in hypotensive patients and those whose landmarks are obscured by oedema or obesity.

Arterial cannulation often results in blood spillage. Universal precautions should be used.

Clean the puncture site and establish a sterile field.

Gently palpate the artery and inject local anaesthetic to raise a small intradermal bleb at the puncture site 1 cm distal to the proposed cannulation site.

A Seldinger technique or a direct cannulation technique may be used.

Seldinger technique

Advance needle through the puncture site towards the artery at a shallow angle. As the vessel is punctured, a flashback of arterial blood is seen in the hub. Pass the guide wire through the needle into the artery. Withdraw the needle and pass the cannula over the guide wire. The guide wire is then discarded.

Direct cannulation

Either: advance the cannula and needle through the puncture site towards the artery at a shallow angle. As the vessel is punctured a flashback of arterial blood is seen in the hub. Holding the needle still, advance the cannula over the needle into the artery. This should be a single smooth movement without resistance.

Or: advance the cannula at a steeper angle and, after observing the flashback, continue through the artery to transfix it. Withdraw the needle slightly from the cannula and then pull the cannula back gently until the tip is in the artery and flashback is again observed. Advance the cannula into the artery.

Following cannulation

Attach extension tubing and three-way tap.

Aspirate blood from the line to confirm placement and to remove any air bubbles, then flush line with saline.

Secure in place and cover with occlusive dressing.

(If using stitches, do not place stitches too deeply. It is possible inadvertently to damage peripheral arteries.)

Attach the arterial catheter to a pressure transducer and flushing device.

Ensure catheter clearly labelled as ‘arterial’ to prevent inadvertent injection of drugs.

Complications of arterial cannulation are shown in Box 15.1.

Vascular compromise may occur at any stage. Inadvertent injection of drugs into an arterial catheter is an important avoidable cause of morbidity and all cannulae and lines should be clearly labelled. Risk of infection increases with time. Any manifestly infected catheter should be removed. After removal press firmly for at least 5 min.Occasionally, persistent bleeding may require a suture (5/0 nylon) to close the skin wound and then further pressure.

If the blood pressure displayed by the invasive arterial monitoring differs from that obtained by non-invasive methods this is usually the result of either damping or resonance in the invasive monitoring. In most cases the mean arterial pressures are usually in close agreement.

Check the arterial line is correctly sited and flush the lumen with heparinized saline.

Check that there are no air bubbles in the connecting tubing or transducer chamber.

Check zero on invasive monitoring.

Check that the transducer is at the level of the left atrium.

In some cases, peripheral vasospasm may be a cause of this error. If in doubt, resite the arterial line, or use the non-invasive measurements of blood pressure. In this case, the line can still be retained for arterial blood gas sampling.

Central venous access is almost universal in intensive care patients. Indications include:

monitoring of CVP

drug administration

total parenteral nutrition

fluid resuscitation

insertion of temporary pacing wires

insertion of pulmonary artery catheters

dialysis

lack of peripheral venous access.

These are relative, but include inability to identify landmarks, limited sites for access, previous difficulties or complications, severe coagulopathy, thrombocytopenia and local sepsis. In addition, if an awake patient is unable to lie flat, central venous cannulation may be impractical.

The use of ultrasound to guide central venous access procedures is recommended in all cases (NICE Guidance. Central venous catheters, ultrasound locating devices, Sept. 2002. www.nice.org.uk/guidance/TA49).

Ultrasound allows for:

direct visualization of the vessels (artery and vein) and their associated structures

identification of thrombosis, valve or anatomical abnormalities

identification of target vessel

first-pass cannulation in the midline of a vessel directly avoiding other vital structures

visualization of guide wire and cannula entering vein

reduction of puncture-related complications.

Use of ultrasound clearly requires understanding of the ultrasound appearances of the anatomy at the various sites of interest. Arteries can be distinguished from veins by their round cross-section, non-compressibility and their pulsatility. Veins, by contrast, show respiratory fluctuation and are easily compressible. When using ultrasound for vascular access you should:

Ensure you are familiar with the device available.

Ensure depth settings, gain and other settings are appropriate.

Place the monitor opposite you at eye level.

Ensure correct orientation of the probe (vessels should be in the anatomical orientation as it would appear from where you are standing.

Identify patent target vessel. (To exclude thrombus in a vein ensure it empties completely with pressure.)

Identify collateral structures to avoid artery, nerves, chest wall and pleura.

Use sterile ultrasound gel and a sterile sheath to maintain sterility.

Puncture the vessel of choice using real time guidance to direct the needle into the vein using longitudinal or transverse approaches.

Verify intravenous placement of the needle, guide wire and catheter with ultrasound.

Traditional approaches to the central veins are described below.

Right sided internal jugular vein cannulation is associated with a lower incidence of complications and higher incidence of correct line placement than other approaches. It is especially appropriate for patients with coagulopathy or those patients with lung disease in whom pneumothorax may be disastrous. It may be best avoided in those patients with carotid artery disease or those with raised intracranial pressure because of the risks of carotid puncture and of impaired cerebral venous drainage. Internal jugular cannulation is associated with a higher incidence of catheter infection than subclavian cannulation but both have a much lower infection rate than the femoral approach.

The internal jugular vein runs from the jugular foramen at the base of the skull (immediately behind the ear) to its termination behind the posterior border of the sternoclavicular joint, where it combines with the subclavian vein to become the brachiocephalic vein. Throughout its length it lies lateral, first to the internal and then common carotid arteries, within the carotid sheath, behind the sternomastoid muscle (Fig. 15.1A). Ultrasound demonstrates the close proximity of the vein to the carotid artery (Fig. 15.1B). Many approaches to the internal jugular vein have been described. A typical landmark approach is from the apex of the triangle formed by the two heads of the sternomastoid (Fig. 15.1).

Slightly extend the neck.

Turn the head slightly to the opposite side.

Palpate the carotid artery at the level of the cricoid cartilage.

Look for the internal jugular vein pulsation. If compressed, the internal jugular can usually be seen to empty and refill.

Introduce the needle from the apex of the triangle at an angle of 30° and aim towards the ipsilateral nipple.

Often when attempting to puncture the vein it collapses under the pressure of the needle and puncture is not recognized. The vessel may then be located by aspirating as the needle is slowly withdrawn. Blood is aspirated as the needle tip passes back into the vein, which refills once the pressure has been removed.

Typical catheter length required is 15 cm from the right and 20 cm from the left. The right side is preferred because left-sided catheters have to traverse two ‘corners’ to get to the SVC and are associated with a higher complication rate.

Fig. 15.1 (A) Approach to the internal jugular vein. (B) Ultrasound appearance of internal jugular vein. Right side viewed from the head of the patient. IJ internal jugular vein, C, carotid artery.

The external jugular vein lies superficially in the neck, running down from the region of the angle of the jaw, across the sternomastoid before passing deep to drain into the subclavian vein. It can be used to provide central venous access, particularly in emergency situations when a simple large-bore cannula can be used for the administration of drugs and resuscitation fluids. Longer central venous catheters can be sited via the external jugular but the angle of entry to the subclavian vein often leads to inability to pass guide wires centrally and results in a high failure rate.

Subclavian vein cannulation is associated with a higher incidence of complications, particularly pneumothorax, and a higher incidence of incorrect line placement than right internal jugular cannulation. It is, however, more comfortable for the patient long-term and is associated with a lower incidence of line infection than other sites of central venous cannulation.

The subclavian vein is a continuation of the axillary vein. It runs from the apex of the axilla behind the posterior border of the clavicle and across the first rib to join the internal jugular vein, forming the brachiocephalic vein behind the sternoclavicular joint. See Fig. 15.2.

Position the patient supine (some people advocate placing a sandbag between the patient’s shoulder blades, which allows the shoulders to drop back out of the way).

Identify the junction of medial third and outer two-thirds of the clavicle.

Introduce the needle just beneath the clavicle at this point, and aim towards the clavicle until contact with bone is made.

To locate the vein, redirect the needle closely behind the clavicle and towards the suprasternal notch.

Fig. 15.2 Approach to the subclavian vein.

Ultrasound can be used to guide cannulation of the subclavian vein using a more lateral approach. The axillary vein can be identified in the apex of the axilla at a depth of 3–4 cm in the average patient. Cannulation of the axillary vein is relatively straightforward under ultrasound control and minimizes the risk of pneumothorax owing to its position lateral to the pleura and chest wall. Longer catheters (20 cm left and 25 cm right) are required by this approach.

The femoral vein lies medial to the femoral artery immediately beneath the inguinal ligament. It is particularly useful for obtaining central access in small children and in patients with severe coagulopathy.

Palpate the femoral artery.

To locate the vein, introduce the needle 1 cm medial to the femoral artery close to the inguinal ligament. It is a common mistake to go too low where the superficial femoral artery overlies the vein. Long catheters, 24 cm plus, are required to get the tip of the catheter into the IVC, which may be required for good flows (e.g. for dialysis).

Ultrasound can be used to identify the vessels and ensure that the vein is punctured near the inguinal ligament where the artery and vein lie side by side. See Fig. 15.3.

Fig. 15.3 Ultrasound appearances of right femoral vein (FV) and femoral artery (FA), viewed from below, at the level of the inguinal ligament. Below this level the superficial femoral artery partially overlaps the vein and the long saphenous vein and other superficial veins join making access more difficult.

The catheter should lie along the long axis of the vessel and the distal segment and tip should be in the superior vena cava (SVC) or at the junction of the SVC and right atrium but ideally outside the pericardial reflection. Catheters below this level may perforate the heart and cause cardiac tamponade. The pericardial reflection lies below the level of the carina and this can therefore be used as a radiological marker. Catheters placed via subclavian veins of left internal jugular vein must not be allowed to lie with the tip abutting the wall of the superior vena cava. This may cause pain, perforation and accelerated thrombus formation. Either advance the catheter to lie in the long axis of the SVC or pull it back to lie in the brachiocephalic vein. See Fig. 15.4.

Fig. 15.4 Optimal position for tip of central catheters on chest X-ray.

Check position (ultrasound and / or landmarks) and try again. If unsuccessful do not persist with repeated passages of the needle in the hope of striking oil! You may have misinterpreted the landmarks, or the vein may be absent or occluded (e.g. with thrombus). Seek help.

Check needle position by drawing back on the syringe; good flow is essential. Adjust the angle of incidence of the needle to the vein to improve flow. Tip the patient further head down to further distend the vein. Try rotating the needle through 180° and draw back again. Remember, the wire must pass easily without force. If this doesn’t work, re-puncture the vein at a slightly different angle.

Occasionally, particularly if using a technique where the wire passes through the barrel of the syringe, it is difficult to know whether you have hit the artery or the vein. In this case it is important to avoid passing a large central venous catheter into the vessel which if arterial could result in vessel damage, stroke or TIA. Consider the following:

Remove the syringe from the needle and observe for pulsatile flow.

Connect a transducer directly to the needle in the vessel and look at the waveform.

Pass the wire into the vessel and remove the needle. Pass an 18-gauge i.v. cannula over the wire into the vessel and remove the wire. Attach a transducer or manometer set directly to the cannula. When venous placement is confirmed, pass the wire back through the i.v. cannula and continue as before.

Complications of central venous cannulation depend in part on the route used but include those in Box 15.2.

The management of pneumothorax depends upon the size of the pneumothorax and the patient’s condition, particularly whether they are ventilated or not. A small pneumothorax in an unventilated patient with good gas exchange may be observed, or aspirated using a small-bore cannula and syringe with three-way tap. Larger pneumothoraces, those that fail to resolve or those that cause any impairment of gas exchange and / or haemodynamics require a formal chest drain. Any significant haemothorax should be formally drained as soon as possible. Once blood has clotted in the chest, drainage is difficult. (See Chest drainage, p. 418.) Seek cardiothoracic / surgical opinion.

Bleeding around the puncture site can occasionally be a persistent problem. If this does not resolve with pressure, use a suture (5/0 nylon) to tie a purse string around the puncture site. This usually stops the bleeding.

Thrombus formation around central venous cannula is common and may lead to deep venous thrombosis and / or pulmonary embolus. Avoid insertion at sites where there is evidence of thrombus on ultrasound scanning. If thrombi are identified around an existing cannula, these should be removed and therapeutic anticoagulation commenced unless contraindicated.

If new central venous catheters are required these should usually be placed at a clean site. Occasionally it may be necessary to change a catheter over a guide wire using an existing site. The technique is similar to that described above for placing any central venous catheter. The main problem is avoiding contamination of the new catheter.

Cut sutures and remove the dressing from the old line before scrubbing.

Use universal precautions, aseptic technique, gown and gloves.

Clean and prepare area (including old catheter).

Pass the wire down the central lumen of the old central venous catheter. (Make sure that the new wire is longer than the old CVP line.)

Remove the old catheter, leaving the wire in place, and send the tip of the old catheter for culture.

Clean the puncture site with antiseptic solution.

Use the wire to site the new line as required.

Removal of central venous catheters can precipitate air embolism, pneumothorax, haemothorax, embolization of thrombus and bacteraemia / sepsis.

Before removing central lines ensure that all drugs and infusions have been stopped or relocated to other lines. Lay the patient down to reduce the risk of air embolism and remove the line smoothly, applying pressure to the puncture site. Apply an occlusive dressing, then sit the patient up. If infection is suspected, send the tip of the line in a dry specimen pot for culture. (See Catheter-related sepsis, p. 340.)

Introducer sheaths are available in a number of sizes for different applications, including insertion of pulmonary artery catheters and temporary pacing wires. In adults, 7.5 or 8.5 Fr are generally used. They may be used as large-bore access for volume resuscitation. Smaller sheaths may be used for introducing specialized monitoring such as jugular bulb oximetery. Large-bore double lumen dialysis catheters are used for haemodialysis, haemofiltration, plasma exchange and rapid transfusion.

See Central venous cannulation above.

All these devices are inserted using a Seldinger technique and a large stiff dilator is used to dilate the initial needle track sufficiently to allow the large-bore catheter to be passed easily into the vessel. These dilators do not pass around tight bends easily and can readily damage or perforate vessels. The left internal jugular vein is best avoided. Introducer sheaths can usually be sited safely at all other sites. Dialysis catheters may be best placed by the right internal jugular or femoral routes. The femoral route may be particularly appropriate in patients with chronic renal failure, to preserve the venous drainage of the arm for subsequent AV fistula formation.

Universal precautions.

Aseptic technique, sterile gown and gloves.

Enter vein with needle, as for central venous line, and pass Seldinger wire.

Make small nick in the skin with a blade.

Either: Pass the sheath mounted on the introducer / dilator over the wire into the vein. The dilator is generally longer than needed and does not need to be passed right up to the hub. When the dilator has entered the vein, slide the sheath forward without advancing the dilator any further.

Or for dialysis catheters, pass the dilator over the wire into the vein then remove dilator and introduce catheter over the wire.

Remove wire and dilator.

Draw back and flush catheter with (heparinized) saline. (For dialysis catheters use heparin 1000 units/mL and flush to the volume of the catheter printed on the hub.)

When in situ and not in use the sheath port should be occluded with an obturator.

Get CXR to check position and complications.

You should ensure that the line used is of an adequate length. It is best if the tip of the line lies freely within a great vein so that the risk of obstruction due to it abutting the vessel wall or being trapped in a ‘collapsing’ vein is minimized. A line longer than 24 cm is often needed to pass from the femoral vein to the lower IVC.

This may be due to a dilated RV or low CO. Do not persist if unsuccessful:

Remove completely, check direction of curvature of catheter and try again.

To enter RV place patient head down and left side up.

To enter PA place patient head up and supine.

PA catheterization is not without risk and is certainly not a therapeutic manoeuvre in its own right! If patients are to benefit then regular collection and interpretation of haemodynamic and oxygen delivery variables, together with the appropriate therapeutic response, is required.

Potential complications of pulmonary artery catheterization are shown in Table 15.1.

TABLE 15.1 Complications of pulmonary artery catheterization

Cardiac tamponade.

Large pericardial effusions.

To obtain diagnostic pericardial fluid.

Small localized effusions, not causing haemodynamic compromise and without diastolic collapse on echocardiogram, do not require pericardiocentesis. Seek senior advice. A cardiology opinion should be sought where available. Use ultrasound guidance in all cases where possible to guide safe drainage, avoiding the liver and other structures. (See Cardiac tamponade, p. 108.)

Performed carefully, complications are few. They include pneumothorax, ventricular tachycardia, myocardial puncture and damage to the coronary arteries. A repeat CXR and echocardiogram should be performed after the procedure to confirm adequate placement and drainage and to identify any problems.

Insertion of a pericardial drain should only be considered a temporary measure. Seek cardiothoracic surgical advice regarding repair of the underlying problem and / or creation of a pericardial window.

Ensure the patient is adequately sedated / anaesthetized. This may require supplementation of existing sedation / analgesia with a small bolus dose of midazolam, opioid or other similar agent. Conscious patients will require anaesthesia, usually with a cardiostable drug (e.g. etomidate) or volatile agent Seek anaesthetic support.

Place conducting gel pads over the patient’s apex and sternum,

Select the appropriate mode (asynchronous or synchronous) and select required energy levels (see relevant algorithms) before removing the paddles from the defibrillator.

Take paddles from the defibrillator and place immediately on to gel pads on the patient. Only charge the paddles once they are in contact with the patient.

Before charging paddles give an ‘all clear’ warning to ensure that no-one is touching the patient and check that everyone is clear.

Before delivering the shock, give a second all clear warning; check that everyone is clear and that any oxygen source is temporarily removed from the patient. Ensure that you yourself are not inadvertently in contact with the patient.

Deliver shock.

After delivery of the shock, several seconds may pass before monitors yield an ECG trace. Keep paddles in contact with the patient if you may wish to deliver a further shock, or return them to the safe position on the defibrillator.

If normal rhythm is not restored seek expert help. Consider:

Higher energy shock.

Alternative paddle position (e.g. cardiac long axis, anteroposterior).

Use of antidysrhythmic drug before repeat attempts.

Many patients on ICU develop atrial fibrillation that does not return to sinus rhythm for more than a very short period after DC cardioversion, until their underlying condition has improved.

These fall broadly into three groups: relieving airway obstruction, protection of the airway from aspiration and facilitation of artificial ventilation of the lungs. Typical indications are given in Box 15.4.

Patients requiring intubation in ICU frequently have limited physiological reserve and are liable to haemodynamic collapse. Drugs used to facilitate intubation must therefore be used judiciously. In some cases patients may already have a markedly obtunded conscious level and small doses of benzodiazepines (e.g. diazepam 5–10 mg) may be all that is required. In other patients, low doses of i.v. anaesthetic agents may be appropriate (e.g. propofol 1–2 mg/kg or etomidate 0.1–0.2 mg/kg); however, these may be associated with cardiovascular collapse.

Muscle relaxants will usually be required to facilitate intubation. Suxamethonium (1–2 mg/kg) is rapid in onset and relatively short-acting in most patients. It is the drug of choice for rapid sequence induction. It has a number of side-effects, however, which limit its use. Atracurium (0.5 mg/kg) is an alternative, but is slower in onset and has a longer duration of action.

The bougie or airway exchange catheter is probably the most useful, simple aid for intubation, In cases of ‘poor view’ the bougie can be passed through the glottis allowing almost blind passage of the endotracheal tube. (railroad tube over the bougie) .Use of a bougie requires relatively little training and can be a lifesaver. You should familiarize yourself with this device. The bougie can also be used for change of an endotracheal tube. Pass bougie down existing tube, then exchange over the bougie.

Potential complications of endotracheal intubation are shown in Box 15.5.

The commonest and most immediately life-threatening complication is oesophageal intubation. Always confirm endotracheal intubation by the presence of expired carbon dioxide using a capnograph or end tidal CO₂ detector device (colour change in presence of CO₂). Note that hypoxia is a late sign of oesophageal misplacement particularly following preoxygenation. If you are in any doubt about the position of the tube, remove it, ventilate by facemask, and start again.

Nasal intubation may provoke epistaxis or predispose to mucosal injury (e.g. submucosal positioning of the tube). In the longer term, nasal intubation may occlude the maxillary antrum and give rise to sinusitis. It is nevertheless better tolerated than oral intubation, particularly during weaning from ventilation. Long-term complications include erosion and stenosis of local tissues, particularly of the larynx and trachea. This may present as airway obstruction and stridor after extubation (see p. 138).

More comfortable than naso- / orotracheal tubes, which allows significant reductions in muscle relaxants, sedative and analgesic drugs. This promotes return of GI tract function.

Patients easily switched from IPPV / assist modes / CPAP / T-piece without the need for extubation and reintubation.

Easier clearance of tracheal secretions by suction.

Speech is possible with cuff deflation or speaking tube.

There may be a lower risk of airway problems after prolonged tracheostomy than after prolonged translaryngeal intubation.

Despite these potential advantages, the large UK TracMan study failed to show significant benefit from early tracheostomy.

These are relative and include:

coagulopathy

distorted or abnormal anatomy

FiO₂ > 0.6

significant haemodynamic instability.

There remains some debate about the relative benefits of percutaneous versus open surgical tracheostomy. Generally percutaneous techniques are associated with less bleeding complications, a lower risk of surgical site infection and better cosmetic result. Otherwise there is little evidence to suggest one is better than the other. Percutaneous techniques are appropriate for most patients on intensive care. Occasional patients with anatomical problems may benefit from an open surgical approach.

There is a wide range of tracheostomy tubes commercially available. Check what is available in your unit and seek advice on the appropriate choice for different clinical situations. Soft and flexible tubes provide maximum patient comfort, minimizing trauma to trachea and associated structures. More rigid tubes may be preferred in the longer term as they better maintain stoma patency and are easier to change. Cuffed tubes provide airway protection and facilitate intermittent positive pressure ventilation. Disadvantages include the risk of excessive cuff pressure, difficulty in swallowing and communication. Cuff pressure should not exceed 25 cm H₂O (18 mmHg) to reduce the risk of mucosal damage, and subsequent tracheal stenosis. Conventional length tracheostomy tubes may occasionally be too short and tubes with adjustable length flanges are available.

Explain to the patient (and relatives) what you are going to do. Get written or verbal consent. Check the patient’s coagulation status. Position the patient flat with the head and neck extended over a pillow. The majority of patients are already intubated and ventilated and are given either an intravenous or volatile anaesthetic. This is supplemented by infiltration of the surgical area with 10 mL of local anaesthetic plus adrenaline (epinephrine), which helps reduces skin edge bleeding.

A bronchoscope can be passed into the larynx during the procedure (through the endotracheal tube or laryngeal mask). This allows the anaesthetist to ensure that the endotracheal tube is withdrawn to a safe position and allows the operator to visualize the needle puncture of the trachea and the correct placement of guide wire, dilator and tracheostomy tube. A camera system and monitor make this much easier.

Tracheostomy may be safely performed through the cricothyroid membrane or in the subcricoid region. In the UK it is recommended that the tracheostomy stoma should be between the 2nd and 4th tracheal rings. At higher levels there may be an increased risk of laryngeal/tracheal stenosis, which may ultimately necessitate tracheal resection. (Resection may not be possible where the lesion is very high at the level of the first ring.) At lower levels there is an increased risk of haemorrhage from major vessels in the thoracic inlet and subsequent tube changes may be more difficult.

There are a number of different percutaneous tracheostomy kits available. Most require that the trachea is punctured by a needle and a guide wire passed through the needle into the lumen of the trachea. This is then used to guide a tracheal dilator, which creates the tracheostomy, allowing the insertion of a tracheostomy tube. The following notes are a guide only; the exact details of the method of insertion will depend upon the system used.

Check that all necessary equipment is available and prepared.

Position patient flat with the neck extended over a pillow.

Examine the neck and ascertain the position of the trachea. Look for anatomical abnormalities, large veins or palpable arterial pulsation. (Ultrasound gives good images of deeper vessels that may be at risk during the procedure.)

Clean the skin.

Palpate the cricothyroid membrane and sternal notch. Infiltrate the skin with 1% lidocaine (lignocaine) and adrenaline (epinephrine), midway between the two.

Make a 2-cm superficial incision horizontally across the midline.

Use blunt forceps and a finger to dissect the pretracheal tissue until you can feel the tracheal rings and identify the level. If necessary, tie off the anterior jugular veins, which occasionally bleed.

Ask the anaesthetist to withdraw the endotracheal tube until the tip is just within the larynx.

Puncture the trachea with the introducer needle below the level of the first tracheal ring and in the midline. Using a saline-filled syringe, confirm the position of the needle by aspiration of air/mucus from the trachea. A bronchoscope passed through the endotracheal tube can also be used to confirm the correct position of the needle tip within the tracheal lumen. A green seeker needle may be helpful if difficulties are encountered in cannulating the trachea.

Pass the guide wire through the needle into the trachea and remove the needle.

Dilate the trachea according to the manufacturer’s instructions supplied with the tracheostomy kit used and insert the tracheostomy tube, again according to instructions.

Remove the introducer and guide wire.

Suck out any blood from the trachea. Blood clot in the airway may produce total airway obstruction or act as a ball valve, allowing gas in but not out.

Inflate the cuff and ventilate the patient through the tracheostomy.

Correct placement of the tube may be confirmed by bronchoscopy or capnography. (Bronchoscopy has the advantage of being able to confirm the position of the tracheal tube in relation to the carina.)

Check that chest expansion is symmetrical and that there are bilateral breath sounds, and that oxygen saturations are maintained.

Tie the tracheostomy tube in place using tracheostomy tapes. In addition, it is advisable to place two stay sutures through the wings of the tracheostomy tube to prevent early accidental decannulation.

Obtain a chest X-ray to confirm position and exclude any complications.

Heavy bleeding from the wound may sometimes occur, particularly if an anterior jugular vein is damaged. If possible place a clip on the bleeding vessel and tie off. Otherwise pack the wound with gauze, apply pressure and wait. If you are near the end of the procedure insert the tracheostomy tube, as this will often tamponade the bleeding. If bleeding does not stop, consider removing the tracheostomy tube (reintubate the patient via the oral route and pass the endotracheal tube beyond the stoma), pack the wound and seek surgical assistance.

This usually means that the tracheostomy tube has been misplaced. Do not persist as this may produce a tension pneumothorax! Remove the tracheostomy tube and reintubate the patient by the oral route.

The potential complications of percutaneous tracheostomy are shown in Box 15.6.

Air emphysema is common but, unless accompanied by a pneumothorax, is usually unimportant and will resolve over time. Pneumothorax is generally the result of attempting to ventilate the patient through a misplaced tube, resulting in air tracking down into the mediastinum and pleural cavities.

Patients with tracheostomy tubes should receive adequate humidification of inspired gases to prevent drying, and regular suction to remove secretions. Spare tracheostomy tubes of the same size and one size smaller should be kept at the bedside, together with a pair of tracheal dilators.

Tracheostomy tubes with changeable inner tubes can remain in place up to 30 days. A disadvantage is that the diameter of the inner lumen will be reduced by 1–2 mm, increasing work of breathing. Fenestrated tubes allow airflow through the vocal cords when the tube is occluded or a speaking valve is attached, but increase the potential for aspiration of gastric contents. They are unsuitable for use in ventilated patients.

Tracheostomy tubes can be changed at any time if necessary, but it is more difficult if the tract is not well established. Administer 100% oxygen and position as for performing a tracheostomy. Pass a large-bore suction catheter (with the end cut off) or gum elastic bougie through the old tracheostomy tube before removing it and use this as a guide to insert the new tube. Facilities for ventilating the patient with a bag and mask and for reintubation should be available in case of difficulty.

When the patient’s condition has improved, the question of when to remove the tracheostomy tube inevitably arises. Consideration should be given to the following:

respiratory effort

volume of tracheal secretions and ability to cough effectively

laryngeal competence and ability to swallow pharyngeal secretions

general condition and strength (can they hold their head up?)

conscious level.

The ability to cough sputum forcibly out of the tracheostomy tube is probably the most useful indicator of likely successful decannulation. There is a general tendency to leave tracheostomy tubes in the convalescent patient for too long. There is no difficulty in a trial of decannulation, providing the track is well formed (5–7 days after insertion). If decannulation fails, reinsert the tracheostomy tube.

It is not routine practice to suture stomas: they are usually left to granulate on their own. A simple occlusive dressing should be applied over the stoma. Ideally, patients should be seen in an ICU follow-up clinic. If tracheal stenosis or other problems develop, appropriate referral (ENT or thoracic surgery) should be made.

Explain to the patient what you are going to do. Get written or verbal consent if appropriate. Check the patient’s coagulation status. Position the patient comfortably with the head and neck extended over a pillow. Then:

Palpate anatomy to identify the cricothyroid membrane.

Clean the neck with antiseptic solution.

Infiltrate over the cricothyroid membrane with 2–3 mL of local anaesthetic.

Warn the patient that you are going to make him or her cough and perform cricothyroid puncture with a green 21-gauge needle. Aspirate air to confirm the tracheal position of the needle and rapidly inject 2 mL of lidocaine (lignocaine). Wait for coughing to subside.

Perform a superficial skin incision.

Pass the introducing needle into the trachea and aspirate air.

Pass the guide wire through the needle and then remove the needle.

Pass the introducer over the guide wire and then slide the cricothyroidotomy / minitracheostomy tube off the introducer. Remove the introducer and guide wire together, leaving the cricothyroidotomy / minitracheostomy in place. Suction to remove any blood.

Confirm correct placement by detection of CO₂.

Obtain CXR to verify the position.

The complications of minitracheostomy are the same as for formal tracheostomy. Misplacement and bleeding are particular problems.

These are relative. Patients with high airway pressures, critical oxygenation, cardiovascular instability or raised intracranial pressure may not tolerate bronchoscopy.

The bronchoscope should be leak-tested and sterilized before use. This generally takes about 20 minutes. Most hospitals will have automatic washers for this.

Before commencing the procedure, check that the size of the patient’s endotracheal tube is adequate to allow bronchoscopy. Tubes smaller than 8 mm internal diameter may be significantly occluded by the bronchoscope, making ventilation and oxygenation of the patient difficult. There are smaller diameter fibreoptic scopes available specifically to aid fibreoptic intubation that may be useful in this situation.

Attach the swivel connector to the patient’s endotracheal or tracheostomy tube.

Ventilate the patient on 100% oxygen prior to and during the bronchoscopy.

Adequately sedate the patient and then give a small dose of muscle relaxant (such as atracurium) to prevent the patient biting or coughing on the bronchoscope. Instil 3–5 mL of local anaesthetic (e.g. 1% lidocaine (lignocaine)) down the trachea. It is sensible to have an assistant to look after patient sedation and ventilation while you perform the bronchoscopy.

Bronchoscopy should be a clean procedure to avoid contaminating the patient’s airway.

Lubricate the scope with a small amount of lubricant jelly. Avoid getting it over the lens.

Pass the bronchoscope through the bung on the swivel connector and into the endotracheal or tracheostomy tube. Continue forward under direct vision.

Pass the scope forward to the carina. Then explore each side of the bronchial tree in turn. Identify and enter each lobar and segmental bronchus (Fig. 15.8). Take note of any abnormal anatomy and remove any secretions.

If there are thick secretions that cannot be sucked up the scope, try instilling 10–20 mL of sterile saline down the suction port of the bronchoscope. This may help to loosen them. Large plugs and blood clots may be dragged out on the end of the scope.

To obtain microbiology specimens place a sputum trap in between the bronchoscope and the wall suction. Use a separate trap for each side. Be careful to keep the sputum trap upright to prevent the secretions disappearing down the suction tubing. Also remove sputum traps before removing the scope from the patient to prevent specimens being contaminated with upper airway flora.

Trainees in intensive care should not perform bronchial biopsy. If you see a suspicious lesion that you think is a tumour or something else, leave it. Call for help to ascertain how to diagnose/manage the problem. Note that clotted blood over time becomes white and can mimic tumour appearances to the uninitiated.

Following bronchoscopy, perform a CXR to exclude pneumothorax and look for improvement in lung expansion where large sputum plugs have been removed.

Ensure the scope is washed and sterilized according to your hospital policy.

Fig. 15.8 Anatomy of the bronchial tree.

BAL may be used to obtain specimens in any patient with pneumonia. It is of particular value in investigating pneumonia in the immunocompromised patient. In addition to conventional pathogens such as Streptococcus pneumoniae and Haemophilus influenzae, other likely pathogens in these patients are Pneumocystis carinii, either alone or with a co-pathogen, Mycobacterium species including tuberculosis, cytomegalovirus and fungi. Discuss the clinical situation with a microbiologist before performing the BAL. He or she will advise on appropriate specimens and tests (see below).

This has the advantage that the operator can be highly selective in the area for lavage in the case of localized disease. It is, however, more invasive and operator-dependent.

During bronchoscopy advance the bronchoscope into a subsegmental bronchus until it wedges.

Instil 100 mL of saline down the suction channel.

Aspirate and collect into a sputum trap.

Repeat from left / right lung and or different segments as required.

BAL catheters consist of a protective outer sleeve and an inner suction catheter. The suction catheter can be connected via a three-way tap to suction and a syringe for instilling saline. This should be a clean procedure and you should wear apron, gloves and goggles.

Preoxygenate the patient with 100% oxygen.

Pass the catheter, with inner tube protected, into the airway, beyond the endotracheal tube.

Advance the inner protected suction catheter forwards until it meets resistance. Do not use undue force.

Perform BAL according to local protocol. Generally 80–100 mL of saline are instilled down the suction catheter, and then aspirated into two or three sputum traps. Not all the saline may be aspirated. This does not matter, it will be absorbed.

Withdraw the inner suction catheter into the protective sleeve before removing from the patient.

Having performed a BAL, telephone the laboratory and then send samples immediately with full diagnostic information and appropriate requests (Box 15.7).

Chest drains are indicated for the drainage of air (pneumothorax), blood (haemothorax), fluid (pleural effusion), pus (empyema) and lymph (chylothorax) from the pleural cavity. In critically ill patients pleural fluid is a common finding on chest X-rays.

Ultrasound is the best method of assessing pleural effusions at the bedside. Pleural fluid is seen as a black echo-poor medium between the two layers of the pleura. In most cases unless the effusion is large or ventilation is clearly compromised there is no need to drain this fluid. The effusion will resolve as the patient’s condition improves. Collections greater than 1–2 cm in depth over a large proportion of the chest, are likely to be significant and may require drainage. Smaller effusions may be tapped / drained for diagnostic purposes, e.g. to identify infection / tumour.

Blood in the pleural cavity should be drained as soon as possible. Once it becomes clotted it will not drain readily and thoracotomy may be required to remove the clot and allow the lung to re-expand.

Chest drains are of two types. Traditionally large-bore tubes, particularly suitable for draining blood or pus, have been placed manually through an incision made in the chest wall directly into the pleural cavity. More recently, Seldinger versions have become available. Seldinger drains should only be used ‘blindly’ to drain obvious large collections because of the risk that the introducer needle may damage the lung. For smaller collections, Seldinger drains should be placed under ultrasound guidance to reduce the risks of needle damage.

This is partly dictated by the position of the collection clinically and radiographically. In the case of long-standing collections, which may be loculated, ultrasound guidance may be helpful. In all other cases the drain should be sited in the 5th intercostal space, just anterior to the midaxillary line, and can be directed cephalad for air and caudally for fluid or blood. All drains should be placed immediately above the rib to avoid damage to the neurovascular bundle, which lies underneath.

The stiff non-compliant lung full of secretions and fluid may not re-expand immediately but should do so over time.

Reassess diagnosis and position of tube.

Is tube ‘swinging’ or is it blocked/kinked? Is the effusion loculated?

Consider low-pressure suction (wall suction or pump 10–20 mmHg).

Increase tidal volume or add 10 cm of PEEP.

Consider the need for CT scan and surgical referral (see below).

The combination of persistent air leak and non-compliant lungs (e.g. ARDS) may make adequate ventilation and gas exchange impossible. Urgent thoracic surgical opinion may be required (Box 15.8).

Chest drains can be removed when they are no longer needed. In practice, this means that if the clinical and CXR findings that required a chest drain have resolved, and the drain is no longer bubbling or draining fluid, it can be removed.

Clean the site with antiseptic solution.

Cut the retaining suture, remove the drain and occlude by pressing.

On removing the drain, ask the patient (if breathing spontaneously) to hold their breath.

Close the wound with a suture. If this is already in situ it can be tied as the drain is removed to reduce any air entrainment. (Avoid purse strings, as above.)

Cover with sterile occlusive dressing.

Obtain a CXR.

Nasoduodenal / nasojejunal feeding tubes are fine-bore soft tubes designed for long-term use. They are usually provided with the feeding tube mounted on a wire insert, which stiffens the tube during placement and helps X-ray determination of position. This is removed once the tube is in place.

The main difficulty in passing these feeding tubes is getting them to pass through the pylorus. The simplest approach is to pass a reasonable length of tube into the stomach (as for NG tube above) and leave for a few hours before getting an abdominal X-ray. Some tubes will simply migrate into the duodenum/jejunum. Alternatively, transpyloric tubes can be placed using X-ray screening, ultrasound or with endoscopic guidance. Seek advice.

After 24 h the traction should be removed and the oesophageal balloon deflated to assess for bleeding. If bleeding recurs, the balloon can be reinflated for a further period of 24 h; however, the need for intervention becomes increasingly likely. If there is no bleeding the tube is usually left in situ (deflated) for 24 h in case bleeding recurs. After this time the tube can be removed. Endoscopy and sclerosis or banding of varices will usually be required.