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Endotracheal intubationEndotracheal intubation

Indications Indications

An artificial airway is necessary in the following An artificial airway is necessary in the following circumstances :circumstances :

Apnoea – The provision of mechanical ventilation, e.g. Apnoea – The provision of mechanical ventilation, e.g. unconsciousness, severe respiratory muscle weakness, self-unconsciousness, severe respiratory muscle weakness, self-poisoning.poisoning.

Respiratory failure – The provision of mechanical Respiratory failure – The provision of mechanical ventilation, e.g. ARDS, peumoniaventilation, e.g. ARDS, peumonia1111

Airway protection – Unconciousness, trauma, aspiration Airway protection – Unconciousness, trauma, aspiration risk, poisoning risk, poisoning

Airway obstruction – To maintain airway patency, e.g. Airway obstruction – To maintain airway patency, e.g. trauma, laryngeal oedema, tumour, burns trauma, laryngeal oedema, tumour, burns

Haemodynamic instability – To facilitate mechanical Haemodynamic instability – To facilitate mechanical ventilation, e.g. shock, cardiac arrest.ventilation, e.g. shock, cardiac arrest.

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Choice of endotracheal tube Choice of endotracheal tube

Most adults require a standard high volume, low Most adults require a standard high volume, low pressure cuffed endotracheal tube. pressure cuffed endotracheal tube.

The averge sized adult will require a size 9.0mm The averge sized adult will require a size 9.0mm id tube (size 8.0mm id for females) cut to length id tube (size 8.0mm id for females) cut to length of 23cm (21cm for females). of 23cm (21cm for females).

Obviously, different size patients may require Obviously, different size patients may require changes to these sizes and particular problems changes to these sizes and particular problems with the upper airway, e.g. trauma, oedema, may with the upper airway, e.g. trauma, oedema, may require a smaller tube.require a smaller tube.

In specific situations non-standard tubes may be In specific situations non-standard tubes may be used, e.g. jet ventilation, armoured tubes (where used, e.g. jet ventilation, armoured tubes (where head mobility is expected or for patients who are head mobility is expected or for patients who are to be positioned prone), double lumen tubes to to be positioned prone), double lumen tubes to isolate the right or left lung. isolate the right or left lung.

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Route of intubation Route of intubation

The usual routes of intubation are oro-tracheal and The usual routes of intubation are oro-tracheal and naso-tracheal. naso-tracheal.

Oro-tracheal intubation in preferred.Oro-tracheal intubation in preferred. The naso-tracheal route has the advantages of The naso-tracheal route has the advantages of

increased pateint comfort and the possibility of increased pateint comfort and the possibility of easier blind placement; it is also easier to secure easier blind placement; it is also easier to secure the tube. the tube.

However, there are several disadvantages. However, there are several disadvantages. The tube is usually smaller, there is a risk of The tube is usually smaller, there is a risk of

sinusitis and otitis media and the route is sinusitis and otitis media and the route is contrandicated in coagulopathy, CSF leak and nasal contrandicated in coagulopathy, CSF leak and nasal fractures.fractures.

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Difficult intubation Difficult intubation

If a difficult intubation is predicted is should not If a difficult intubation is predicted is should not be attempted by an inexperienced operator. be attempted by an inexperienced operator.

Difficulty may be predicted in the patient with a Difficulty may be predicted in the patient with a small mouth, high arched palate, large upper small mouth, high arched palate, large upper incisors, hypognathia, large tongue, anterior incisors, hypognathia, large tongue, anterior larynx, short neck, immobile temporomandibular larynx, short neck, immobile temporomandibular joints, immobile cervical joints or morbid obesity. joints, immobile cervical joints or morbid obesity.

If a difficult intubation present unexpectedly the If a difficult intubation present unexpectedly the use of a stylet, a straight bladed laryngoscope or use of a stylet, a straight bladed laryngoscope or a fibreoptic laryngoscope may help. a fibreoptic laryngoscope may help.

It is important not to persist for too long; revert to It is important not to persist for too long; revert to bag and mask ventilation to ensure adequate bag and mask ventilation to ensure adequate oxygenation. oxygenation.

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Complications of intubation Complications of intubation

Early complications Early complications Trauma, e.g. haemorrhage, mediastinal perforation Trauma, e.g. haemorrhage, mediastinal perforation Haemodynamic collapse, e.g. positive pressure Haemodynamic collapse, e.g. positive pressure

ventilation, vasodilation, arrhythmias or rapid ventilation, vasodilation, arrhythmias or rapid correction of hypercapnia.correction of hypercapnia.

Tube malposition, e.g. failed or endobronchial Tube malposition, e.g. failed or endobronchial intubation. intubation.

Later complications Later complications Infection including maxillary sinusitis if nasally Infection including maxillary sinusitis if nasally

intubated intubated Cuff pressure trauma (maintain cuff pressure Cuff pressure trauma (maintain cuff pressure

<25cmH2O)<25cmH2O) Mouth /Lip traumaMouth /Lip trauma

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Equipment required Equipment required

Suction (Yankauer tip)Suction (Yankauer tip) Oxyen, rebreathing bag and maskOxyen, rebreathing bag and mask Laryngoscope (two curved blades and straight Laryngoscope (two curved blades and straight

blade)blade) Stylet / bougieStylet / bougie Endotracheal tubes (preferred size and smaller)Endotracheal tubes (preferred size and smaller) Magill forcepsMagill forceps Drugs (Induction agent, muscle relaxant, sedative, Drugs (Induction agent, muscle relaxant, sedative,

anticholinergic)anticholinergic) Syringe for cuff inflationSyringe for cuff inflation Tape to secure tubeTape to secure tube

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TracheostomyTracheostomy

Indications Indications To provide an artificial airway where oro-or naso-To provide an artificial airway where oro-or naso-

tracheal intubation is to be avoided. tracheal intubation is to be avoided. This may be to provide better patient comfort, to This may be to provide better patient comfort, to

avoid mouth or nasal trauma or, in an avoid mouth or nasal trauma or, in an emergency, where there is acute upper airway emergency, where there is acute upper airway obstruction. obstruction.

Converting an oro-or naso-tracheal tube to a Converting an oro-or naso-tracheal tube to a tracheostomy should be considered early in cases tracheostomy should be considered early in cases of difficult intubation to avoid the risks of repeat of difficult intubation to avoid the risks of repeat intubation, or later in caes of prolonged intubation, or later in caes of prolonged intubation to avoid laryngela trauma. intubation to avoid laryngela trauma.

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The exact time that one should consider The exact time that one should consider performing a tracheostomy in caes of prolonged performing a tracheostomy in caes of prolonged intubation is not known although current practice intubation is not known although current practice is at about 10-16days. is at about 10-16days.

High volume, low pressure cuffs on modern High volume, low pressure cuffs on modern endoracheal tubes do not cause more tracheal endoracheal tubes do not cause more tracheal damage than the equivalent cuffs of a damage than the equivalent cuffs of a tracheostomy tube, but avoiding the risks of tracheostomy tube, but avoiding the risks of laryngeal and vocal cord damage may provide laryngeal and vocal cord damage may provide some advantage for tracheostomy. some advantage for tracheostomy.

The reduced need for sedation is a definite The reduced need for sedation is a definite advantage. advantage.

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Percutaneous tracheostomyPercutaneous tracheostomy

A more rapid procedure with less tissue trauma and scarring A more rapid procedure with less tissue trauma and scarring than the standard open surgical technique. than the standard open surgical technique.

Can be performed in the intensive care unit avoiding the need Can be performed in the intensive care unit avoiding the need to transfer patients to theatre. to transfer patients to theatre.

The technique involves infiltration of the subcutaneous tissues The technique involves infiltration of the subcutaneous tissues with lignocaine and adrenaline. with lignocaine and adrenaline.

A1-1.5cm skin crease incision is made in the midline. A1-1.5cm skin crease incision is made in the midline. Subcutaneous tissue is blunt dissected to the anterior tracheal Subcutaneous tissue is blunt dissected to the anterior tracheal wall. wall.

The trachea is punctured with a 14G needle between the 1The trachea is punctured with a 14G needle between the 1stst and 2and 2ndnd tracheal cartilages and a guide wire is inserted into the tracheal cartilages and a guide wire is inserted into the trachea. trachea.

The stoma is created either by progressive dilation to 36Fr The stoma is created either by progressive dilation to 36Fr (Ciaglia technique) or by use of single stage guided dilating tool (Ciaglia technique) or by use of single stage guided dilating tool (Schachner-Ovill technique). (Schachner-Ovill technique).

In the former case the tracheostomy tube is introduced over an In the former case the tracheostomy tube is introduced over an appropriate size dilator and in the latter through the open appropriate size dilator and in the latter through the open dilating tool. dilating tool.

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ComplicationsComplications

The main early complication is haemorrhage, either from trauma The main early complication is haemorrhage, either from trauma to the thyroid isthmus or aberrant superior thyroid vessels. to the thyroid isthmus or aberrant superior thyroid vessels.

Although most early haemorrhage is easily controlled, coagulation Although most early haemorrhage is easily controlled, coagulation disorder in critically ill patients may created additional problems.disorder in critically ill patients may created additional problems.

Tracheal stenos is is related to creation of the tracheal stoma and Tracheal stenos is is related to creation of the tracheal stoma and subsequent low grade infection.subsequent low grade infection.

This is thought to be a greater problem with open surgical This is thought to be a greater problem with open surgical tracheostomies than percutaneous tracheostomies. tracheostomies than percutaneous tracheostomies.

The presence of a foreign body in the trachea, bypassing the The presence of a foreign body in the trachea, bypassing the normal upper airway defence mechanisms, together with an open normal upper airway defence mechanisms, together with an open neck wound, presents an obvious infection risk. neck wound, presents an obvious infection risk.

Subglottic infection is more likely after trans-laryngeal intubation. Subglottic infection is more likely after trans-laryngeal intubation. Tracheo-oesophageal fistula is a rare complication due to trauma Tracheo-oesophageal fistula is a rare complication due to trauma

or pressure necrosis of the posterior wall of the trachea. or pressure necrosis of the posterior wall of the trachea.

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Maintenance of a tracheostomyMaintenance of a tracheostomy

Since the upper air passages have been bypassed Since the upper air passages have been bypassed artificial humidification is required. artificial humidification is required.

Cough is less effective without a functioninglarynx Cough is less effective without a functioninglarynx so regular tracheal suction will be necessary.so regular tracheal suction will be necessary.

Furthermore, the larynx provides a small amount of Furthermore, the larynx provides a small amount of natural PEEP which is lost with a tracheostomy. natural PEEP which is lost with a tracheostomy.

The risk of basal atelectasis can be overcome with The risk of basal atelectasis can be overcome with CPAP or attention to respiratory exercises which CPAP or attention to respiratory exercises which promote deep breathing. promote deep breathing.

A safe fistula forms within 3 days allowing A safe fistula forms within 3 days allowing replacement of the tracheostomy tube. replacement of the tracheostomy tube.

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Tracheostomy tubesTracheostomy tubes

Standard high volume, low pressure cuffStandard high volume, low pressure cuff

Fenestrated with or without cuffFenestrated with or without cuff Useful where airway protection is not a primary Useful where airway protection is not a primary

concern. concern. May be closed during normal breathing while May be closed during normal breathing while

providing intermittent suction access.providing intermittent suction access.

Fenestrated with inner tubeFenestrated with inner tube As above but with an inner tube to facilitate As above but with an inner tube to facilitate

closure of the fenestration during intermittent closure of the fenestration during intermittent mechanical ventilation. mechanical ventilation.

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Fenestrated with speaking valveFenestrated with speaking valve Inspiration allowed through the tracheostomy to reduce Inspiration allowed through the tracheostomy to reduce

dead space and inspiratory resistance. dead space and inspiratory resistance. Expiration through the larynx, via the fenestration, allowing Expiration through the larynx, via the fenestration, allowing

speech and the advantages of laryngeal PEEP.speech and the advantages of laryngeal PEEP.Adjustable flangeAdjustable flange Accommodates extreme variations in skin to trachea depth Accommodates extreme variations in skin to trachea depth

while ensuring the cuff remains central in the trachea.while ensuring the cuff remains central in the trachea.Pitt speaking tube Pitt speaking tube A non fenestrated, cuffed tube for continuous mechanical A non fenestrated, cuffed tube for continuous mechanical

ventilation and airway protection with a port to direct ventilation and airway protection with a port to direct airflow above the cuff to the larynx. airflow above the cuff to the larynx.

When airflow is direct through the larynx some patients are When airflow is direct through the larynx some patients are able to vocalise.able to vocalise.

Sliver tubeSliver tube An uncuffed tube which is used occasionally in ENT practice An uncuffed tube which is used occasionally in ENT practice

to maintain a tracheostomy fistula.to maintain a tracheostomy fistula.

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Defibrillation Defibrillation

Electrical conversion of a tachyarrhythmia to Electrical conversion of a tachyarrhythmia to restore normal sinus rhythm. restore normal sinus rhythm.

This may be an emergency procedure (when the This may be an emergency procedure (when the circulation is absent or severely comporomised), circulation is absent or severely comporomised), semi elective (when the circulation is semi elective (when the circulation is compromised to a lasser degree), or elective compromised to a lasser degree), or elective (when synchronised cardioversion is performed to (when synchronised cardioversion is performed to restore sinus rhythm for a non-restore sinus rhythm for a non-compromisingsupra-ventricular tachycardia).compromisingsupra-ventricular tachycardia).

Synchronisation requires initial connection of ECG Synchronisation requires initial connection of ECG leads from the patient to the defibrillator so that leads from the patient to the defibrillator so that the shock is delivered on the R wave to minimize the shock is delivered on the R wave to minimize the risk of ventricular fibrillation. the risk of ventricular fibrillation.

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Indications Indications Compromised circulation, e.g. VF, VTCompromised circulation, e.g. VF, VT Restoration of sinus rhythm and more effective Restoration of sinus rhythm and more effective

cardiac outputcardiac output Lessens risk of cardiac thrombus formation Lessens risk of cardiac thrombus formation Contraindications / cautionsContraindications / cautions Aware patientAware patient Severe coagulopathySevere coagulopathy Caution with recent thrombolysisCaution with recent thrombolysis Digoxin levels in toxic rangeDigoxin levels in toxic rangeComplicationsComplications Surface burnSurface burn Pericardial tamponadePericardial tamponade Electrocution of bystandersElectrocution of bystanders

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TechniqueTechnique

The chances of maintaining sinus rhythm are The chances of maintaining sinus rhythm are increased in elective cardioversion if increased in elective cardioversion if KK++>4.5mmol/L and plasma Mg>4.5mmol/L and plasma Mg2+2+ levels are normal. levels are normal.

Prior to defibrillation, ensure self and onlookers are Prior to defibrillation, ensure self and onlookers are not in contact with patient or bed frame.not in contact with patient or bed frame.

To reduce the risk of superficial burns, replace To reduce the risk of superficial burns, replace gel/gelled pads after every 3 shocks.gel/gelled pads after every 3 shocks.

Consider resisting paddle position (e.g. antero-Consider resisting paddle position (e.g. antero-posterior) if defibrillation fails.posterior) if defibrillation fails.

The risk of intractable VF following defibrillation in The risk of intractable VF following defibrillation in a patient receiving digoxin is small unless the a patient receiving digoxin is small unless the plasma digoxin levels are in the toxic range or the plasma digoxin levels are in the toxic range or the patient is hypovolaemic.patient is hypovolaemic.

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Temporary internal pacing Temporary internal pacing

When the heart’s intrinsic pacemaking ability When the heart’s intrinsic pacemaking ability fails, temporary internal pacing can be instituted. fails, temporary internal pacing can be instituted.

Electrodes can be endocardial (inserted via a Electrodes can be endocardial (inserted via a cental vein) or epicardial (placed on the external cental vein) or epicardial (placed on the external surface of the heart at thoracotomy). surface of the heart at thoracotomy).

The endocardial wire may be placed under The endocardial wire may be placed under fluoroscopic control or ‘blind’ using a balloon fluoroscopic control or ‘blind’ using a balloon flotation catheter. flotation catheter.

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IndicationsIndications Third degree heart block Third degree heart block Mobitz Type II second – degree heart block when Mobitz Type II second – degree heart block when

the circulation is compromised or an operation is the circulation is compromised or an operation is plannedplanned

Overpacing (rarely)Overpacing (rarely) Asystole (although external pacing is more useful Asystole (although external pacing is more useful

initially)initially)ComplicationsComplications As for central venous catheter insertion As for central venous catheter insertion ArrhythmiasArrhythmias Infection (including endocarditis)Infection (including endocarditis) Myocardial perforation (rare)Myocardial perforation (rare)Contraindications/cautionsContraindications/cautions As for central venous catheter insertion As for central venous catheter insertion

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TroubleshootingTroubleshooting

Failure to pace may be due to :Failure to pace may be due to : No pacemaker output (no spikes seen) – check No pacemaker output (no spikes seen) – check

connections, battery connections, battery No capture (pacing spikes seen but no QRS No capture (pacing spikes seen but no QRS

complex following) – poor complex following) – poor positioning/dislodgement of wire. positioning/dislodgement of wire.

Temporarily increase output as this may regain Temporarily increase output as this may regain capture. Reposition / replace wire.capture. Reposition / replace wire.

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GeneralGeneral

1.1. Check threshold daily as it will rise slowly over 48-96h, Check threshold daily as it will rise slowly over 48-96h, probably due to fibrosis occurring around the electrodes.probably due to fibrosis occurring around the electrodes.

2.2. Overpacing is occasionally indicated for a tachycardia Overpacing is occasionally indicated for a tachycardia not responding to antiarrhythmic therapy or not responding to antiarrhythmic therapy or cardioversion. For SVT, pacing is usually attempted with cardioversion. For SVT, pacing is usually attempted with the wire sited in the right atrium. Pace at rate 20-30bpm the wire sited in the right atrium. Pace at rate 20-30bpm above patient’s heart rate for 10-15sec then either above patient’s heart rate for 10-15sec then either decrease rate immediately to 80 bpm or slowly, by 20 decrease rate immediately to 80 bpm or slowly, by 20 bpm every 5-10sec.bpm every 5-10sec.

3.3. If overpacing fails, underpacing may be attempted with If overpacing fails, underpacing may be attempted with the wire situated in either atrium (for SVT) or, usually, the wire situated in either atrium (for SVT) or, usually, ventricle (for either SVT or VT). A paced rate of 80-100 ventricle (for either SVT or VT). A paced rate of 80-100 bpm may produce a refractory period sufficient to bpm may produce a refractory period sufficient to suppress the intrinsic tachycardia.suppress the intrinsic tachycardia.

4.4. Epicardial pacing performed during cardiac surgery Epicardial pacing performed during cardiac surgery requires sitting of either two epicardial electrodes or one requires sitting of either two epicardial electrodes or one epicardial and one skin electrode (usually a hypodermic epicardial and one skin electrode (usually a hypodermic needle). The pacing threshold of epicardial wires rises needle). The pacing threshold of epicardial wires rises quickly and may become ineffective after 1-2 days.quickly and may become ineffective after 1-2 days.

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Technique (for endocardial electrode Technique (for endocardial electrode placement)placement)

1.1. If using fluoroscopy, move patient to X-ray suite If using fluoroscopy, move patient to X-ray suite or place lead shields around bed area. Place or place lead shields around bed area. Place patient on screening table. Staff should wear patient on screening table. Staff should wear lead aprons.lead aprons.

2.2. Use aseptic technique throughout. Insert 6Fr Use aseptic technique throughout. Insert 6Fr sheath in internal jugular or subclavian vein. sheath in internal jugular or subclavian vein. Suture in position.Suture in position.

3.3. Connect pacing wire electrodes to pacing box Connect pacing wire electrodes to pacing box (black = negative polarity = distal, red = (black = negative polarity = distal, red = positive polarity = proximal). Set pace maker to positive polarity = proximal). Set pace maker to demand. Check box is working and battery demand. Check box is working and battery charge adequate. Turn pacing rate to > 30 bpm charge adequate. Turn pacing rate to > 30 bpm above patient’s intrinsic rhythm. Set voltage 4V.above patient’s intrinsic rhythm. Set voltage 4V.

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4.4. Insert pacing wire through sheath into central Insert pacing wire through sheath into central vein. If using balloon catheter, insert to 15-20cm vein. If using balloon catheter, insert to 15-20cm depth then inflate ballon. Advance catheter, depth then inflate ballon. Advance catheter, viewing ECG monitor for change in ECG viewing ECG monitor for change in ECG morphology and capture of pacing rate. If using morphology and capture of pacing rate. If using screening direct wire toward the apex of the right screening direct wire toward the apex of the right ventricle. Approximate insertion depth from a ventricle. Approximate insertion depth from a neck vein is 35-40 cm.neck vein is 35-40 cm.

5.5. If pacing impulses not captured, (deflate balloon), If pacing impulses not captured, (deflate balloon), withdraw wire to 15 cm insertion depth then withdraw wire to 15 cm insertion depth then repeat step 4.repeat step 4.

6.6. Once pacing captured, decrease voltage by Once pacing captured, decrease voltage by decrements to determine threshold at which decrements to determine threshold at which pacing is no longer captured. Ideal position pacing is no longer captured. Ideal position determined by a threshold <0.4V. If not achieved, determined by a threshold <0.4V. If not achieved, re-position wire. re-position wire.

7.7. If possible, ask patient to cough to check that the If possible, ask patient to cough to check that the wire does not dislodge.wire does not dislodge.

8.8. Set voltage at 3X threshold and set desired heart Set voltage at 3X threshold and set desired heart rate on demand mode. Tape wire securely to rate on demand mode. Tape wire securely to patient prevent dislodgement.patient prevent dislodgement.

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External pacingExternal pacing

External pacing can be rapidly performed by External pacing can be rapidly performed by placement of two electrodes on the fron and rear placement of two electrodes on the fron and rear chest wall when asystole or third degree heart block chest wall when asystole or third degree heart block has produced acute haemodynamic compromise.has produced acute haemodynamic compromise.

It is often used as a bridge to temporary internal It is often used as a bridge to temporary internal pacing. It can also be used as a prophylactic pacing. It can also be used as a prophylactic measure e.g. for Mobitz Type II second degree heart measure e.g. for Mobitz Type II second degree heart block.block.

Indications Indications Asystole (in conjunction with cardiopulmonary Asystole (in conjunction with cardiopulmonary

resuscitation)resuscitation) Third degree heart blockThird degree heart block Prophylactic Prophylactic Complications Complications Discomfort Discomfort

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Technique Technique 1.1. Connect pacing wire gelled electrodes to pacemaker. Place Connect pacing wire gelled electrodes to pacemaker. Place

black (=negative polarity) electrode on the anterior chest wall black (=negative polarity) electrode on the anterior chest wall to the left of the lower sternum and ed (= positive polarity) to the left of the lower sternum and ed (= positive polarity) electrode to the corresponding position on the posterior electrode to the corresponding position on the posterior hemithorax.hemithorax.

2.2. Connect ECG electrodes from ECG monitor to external Connect ECG electrodes from ECG monitor to external pacemaker and another set of electrodes from pacemaker to pacemaker and another set of electrodes from pacemaker to patient.patient.

3.3. Set pacemaker to demand. Turn pacing rate to >30 bpm Set pacemaker to demand. Turn pacing rate to >30 bpm above patient’s intrinsic rhythm. Set current to 70mA.above patient’s intrinsic rhythm. Set current to 70mA.

4.4. Start pacing. Increase current (by 5mA increments) until Start pacing. Increase current (by 5mA increments) until pacing rate captured on monitor.pacing rate captured on monitor.

5.5. If pacing rate not captured at current of 120-130mA, re-site If pacing rate not captured at current of 120-130mA, re-site electrodes and repeat steps 3-4.electrodes and repeat steps 3-4.

6.6. Once pacing captured, set current at 5-10mA above threshold.Once pacing captured, set current at 5-10mA above threshold.GeneralGeneral In asystole, even though an electrical rhythm is produced by In asystole, even though an electrical rhythm is produced by

the external pacing, this does not guarantee an adequate the external pacing, this does not guarantee an adequate output is being generated.output is being generated.

Although the patient may complain of discomfort, external Although the patient may complain of discomfort, external chest wall pacing is better tolerated and more reliable than chest wall pacing is better tolerated and more reliable than other forms or external pacing e.g. oesophageal.other forms or external pacing e.g. oesophageal.