Methods & Devices
The ‘Malawi device’: a durable, reusable, low cost device from own materials for emergency ventilation during percutaneous tracheostomy
Tropical Doctor 2014, Vol. 44(4) 214–218 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0049475514541649 tdo.sagepub.com
Gregor Pollach1, Felix Namboya2 and Kai Jung3
Abstract The use of a tracheostomy is routine in current intensive care practice to facilitate weaning patients requiring prolonged respiratory support from mechanical ventilation. Percutaneous tracheostomy has become an established technique with an acceptable risk profile in appropriately selected patients, and has the advantage that it can be performed at the bedside without the need for an operating theatre. This is particularly relevant in a resource-poor setting. Ideally, percutaneous tracheostomy requires the presence of two skilled persons; one to perform the tracheostomy while the other controls the airway and withdraws the endo-tracheal tube at the appropriate time. This is not always possible in a resource poor setting with limited manpower. Without two operators, it is possible for the tracheal tube to become displaced before the completion of the tracheostomy with potentially disastrous consequences. We describe a method by which the airway and ventilation can be maintained if accidental tracheal extubation occurs before completion of a percutaneous tracheostomy. The ‘Malawi Device’, a cheap and simple modification of readily available equipment, enables a single operator to maintain the airway and ventilate the patient when the above scenario occurs.
Keywords Equipment, apparatus, device, percutaneous tracheostomy, emergency kit, emergency ventilation
Background Since its first description by Ciaglia1 percutaneous tracheostomy has become a standard procedure in intensive care units all over the world. Under bronchoscopic control2 a Seldinger wire is introduced into the tracheal lumen via a puncture between the cricoid and the first tracheal cartilage. Different types of dilators (multiple dilators,1 single ‘rhino’-dilators,3 dilatation forceps,4 ‘twisting’ dilatation5) are used to widen the opening until a tracheostomy tube can be placed.6 In Malawi’s largest healthcare facility, the Queen Elizabeth Central Hospital, suffering from a resourcepoor and staff depleted situation7 we frequently have to perform a percutaneous tracheostomy alone, dealing with tracheostomy and bronchoscopy at the same time. Alternatively we have to do the procedure without the help of a bronchoscope at all. Despite these difficulties, percutaneous tracheostomy remains an important tool to optimise the use of our precious ICU resources. When performed by the
intensivist, this means independence from the availability of a surgeon,8 as well as the advantage of early weaning from mechanical ventilation and thus earlier discharge from intensive care.1 This is extremely important because at any given moment there are several patients in our hospital in dire need of an intensive care bed.
1 Head of Department and Associate Professor, Department of Anaesthesia and Intensive Care, College of Medicine, University of Malawi, Malawi 2 Deputy Head of Department and Consultant, Department of Anaesthesia and Intensive Care, University of Malawi, Malawi 3 Lead Consultant in Intensive Care, Department of Anaesthesia and Intensive Care, University of Malawi, Malawi
Corresponding author: Gregor Pollach, Associate Professor, University of Malawi, Department of Anaesthesia and Intensive Care Blantyre 3, Chichiri, Blantyre, PO Box 360, Malawi, Africa. Email: [email protected]
Downloaded from tdo.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 24, 2015
Pollach et al.
215
Using the ‘Malawi device’ The challenge There are a number of recognised risks for the patient undergoing tracheostomy, namely injuries to the trachea, bleeding or infection.9,10 A highly hazardous scenario, arising if the tracheal tube is prematurely displaced before the airway is secured via the tracheostomy, results in ‘can’t intubate, can’t ventilate’. An inexperienced assistant (when available) may readily withdraw the tracheal tube too far while trying to make space for the insertion of the tracheostomy. This leaves the operator in the difficult position of having urgently to reestablish the airway either by endo-tracheal intubation or rapid tracheal dilatation. The first means re-scrubbing, and the second is fraught with danger. In our setting it is uncommon to have one experienced anaesthetist available, let alone two. Consequently, the one performing the tracheostomy has to struggle to effect an immediate re-intubation of a non-ventilated patient, who has a half-done tracheostomy.
The solution In order to help this colleague and to deal with this situation we have constructed a simple and cheap device: the ‘Malawi device’. This is available in a prepared kit at the bedside so that it is available for immediate use if required during percutaneous tracheostomy. In the following paragraphs we use as an example the Ciaglia type of tracheostomy. In principle, our idea is applicable to different types of percutaneous tracheostomy sets. If another system, e.g. the ‘twisting dilatation’5 is used, it must be adjusted before its first use. This is not difficult and would mean connecting the dilation device to a ventilation tube for example, instead of an endotracheal tube with the Ambu bag.
Description of the device The device permits emergency ventilation through the dilator in the event that the airway is lost during the early stages of the percutaneous tracheostomy (Figure 1). It consists of a re-sterilised dilator of the size F 21, a shortened tracheal tube size 6.0 (which fits snugly over the F 21 dilator, owing to the flexibility of the material and so ensuring no air leak), a 90 swivel connector with a plug to close the Bronchoscopy port, a curved re-sterilised guide wire and an Ambu bag. The whole set costs less than E1; the self-inflating bag is available in any anaesthesia department. At first glance our set may seem a little complicated and cumbersome, but it is not. It is slim, lightweight, easy to assemble and simple to clean, and it can be assembled with a maximum length of around 50 cm.
The index case. A 48-year-old man was ventilated after he sustained a head injury 3 weeks previously. Weaning was difficult and three extubations failed despite a quite low pressure support and the ability of the patient to survive several hours on a T-piece with 40% oxygen. The patient was known to be difficult to intubate and there was only one anaesthesiologist in the department at that time. The anaesthetic clinical officers were not trained to perform a bronchoscopy on their own. Nevertheless, our ICU, which caters for a 1400-bed hospital with only four to five beds, was full. Referral to another centre was not possible and two young mothers were in dire need of an ICU bed due to peripartum sepsis. The only possibility of admitting at least one of the women was to fashion a tracheostomy on the aforementioned patient and continue his further management in a High Dependency Unit. Unfortunately no experienced surgeon was available to help with a tracheostomy. The anaesthesiologist performed a bronchoscopy on the patient and then started the percutaneous tracheostomy. Owing to the inexperience of the anaesthetic clinical officer responsible for the airway, the endo-tracheal tube was dislodged with the bronchoscope shortly after the percutaneous guide wire was introduced and the first dilations were done. The anaesthesiologist was confronted with an unventilated patient, known to be difficult to intubate, with a dilator in his trachea. The anaesthesiologist followed the prepared plan as described in the text, started to ventilate the patient, and when that proved successful, handed over surveillance of ventilation to the anaesthetic clinical officer. The patient was subsequently re-intubated not without difficulty. The percutaneous tracheostomy could then be re-commenced (Figure 2). Following this episode, it was decided to establish a backup for the lonely anaesthesiologist doing a percutaneous tracheostomy in these less than optimal conditions.
The procedure If the orotracheal airway is lost during the procedure, the device can rapidly be assembled from the pre-prepared and sterilised kit by an assistant. If the Seldinger wire is still located in the trachea and can be seen coming through the dilator, the additional one from the kit can be spared. The shortened tube size 6.0 is advanced over the Seldinger wire and then placed over the dilator size F 21 until it engages with the proximal end of the dilator so as to produce a tight fit. The swivel angle piece adaptor is attached to the 15 mm connector on the 6.0 mm tube allowing the Seldinger wire to protrude from the bronchoscopy port.
Downloaded from tdo.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 24, 2015
216
Tropical Doctor 44(4)
Figure 1. (a) The parts of the ‘Malawi device’: the dilator, the tracheal tube, the swivel connector with opening and plug, the guide wire and the Ambu bag (a paediatric Ambu bag is shown for better visibility in the picture). (b) An important detail – the guide wire fits through the swivel connector and can be fixed through the plug. (c) The set with five ingredient parts, which need to be connected together.
The plug can be inserted into the port both to immobilize the Seldinger wire and produce an airtight seal, allowing manual ventilation via the device using a selfinflating bag. The 6.0 tube connects with the 15 mm connector to the swivel connector via a Seldinger wire which measures approximately 45 cm. Lastly the Ambu bag with oxygen is attached and ventilation can commence. Although the tube and dilator are partially obstructed by the Seldinger wire, oxygenation and adequate ventilation can usually be achieved. Nevertheless the effectiveness of this method must be tested with the particular model of percutaneous tracheostomy available before using the ‘Malawi device’ for the first time on a patient. Once oxygenation of the patient is secure, an assistant can then take over manual ventilation using the self-inflating bag, while the operator can deal with reintubation in a controlled manner.
The diameter of the narrowest point is not specified by the manufacturer. Depending on the size of the Seldinger wire ventilation is possible with a lumen which measures the size of G 12 (purely for the air flow, excluding the Seldinger wire, which is larger than the G 14 size which is in use in emergencies to puncture the cricoid and proceed with jet-ventilation). The G 12 opening can be enlarged when preparing the kit with a very thin Seldinger wire. With this method a tidal volume of 300–400 mL can be achieved. When using 100% oxygen, this is sufficient for oxygenation. Carbon dioxide elimination occurs in the normal way back through trachea. Pressures were actually difficult to measure because ventilation was performed manually with an Ambu bag (and the pressure at the end of the needle does not represent the true ventilation pressure in the bronchi). The creation of a side-hole in the dilator, as suggested in the discussion, greatly improves ventilation parameters.
Downloaded from tdo.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 24, 2015
Pollach et al.
217 Taking out the Seldinger wire is not an option either because then the dilator would slip out of the trachea, considering already the short length the dilator lies in the tracheal lumen. The consequence would be to lose the airway during the manipulations necessary to ventilate the patient. The ‘Malawi device’ overcomes the problem of the presence of the long Seldinger wire, which would otherwise prevent the connection of airway equipment, by allowing the end to leave via the bronchoscopy port of the angle piece where it is anchored by insertion of the sealing plug. The sealing plug prevents migration of the wire and produces an airtight seal. Our solution demonstrates several advantages:
Figure 2. The fully assembled device ready for emergency ventilation. (Registrars were able to assemble it at the mannequin in
The ‘Malawi device’: a durable, reusable, low cost device from own materials for emergency ventilation during percutaneous tracheostomy
Tropical Doctor 2014, Vol. 44(4) 214–218 ! The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0049475514541649 tdo.sagepub.com
Gregor Pollach1, Felix Namboya2 and Kai Jung3
Abstract The use of a tracheostomy is routine in current intensive care practice to facilitate weaning patients requiring prolonged respiratory support from mechanical ventilation. Percutaneous tracheostomy has become an established technique with an acceptable risk profile in appropriately selected patients, and has the advantage that it can be performed at the bedside without the need for an operating theatre. This is particularly relevant in a resource-poor setting. Ideally, percutaneous tracheostomy requires the presence of two skilled persons; one to perform the tracheostomy while the other controls the airway and withdraws the endo-tracheal tube at the appropriate time. This is not always possible in a resource poor setting with limited manpower. Without two operators, it is possible for the tracheal tube to become displaced before the completion of the tracheostomy with potentially disastrous consequences. We describe a method by which the airway and ventilation can be maintained if accidental tracheal extubation occurs before completion of a percutaneous tracheostomy. The ‘Malawi Device’, a cheap and simple modification of readily available equipment, enables a single operator to maintain the airway and ventilate the patient when the above scenario occurs.
Keywords Equipment, apparatus, device, percutaneous tracheostomy, emergency kit, emergency ventilation
Background Since its first description by Ciaglia1 percutaneous tracheostomy has become a standard procedure in intensive care units all over the world. Under bronchoscopic control2 a Seldinger wire is introduced into the tracheal lumen via a puncture between the cricoid and the first tracheal cartilage. Different types of dilators (multiple dilators,1 single ‘rhino’-dilators,3 dilatation forceps,4 ‘twisting’ dilatation5) are used to widen the opening until a tracheostomy tube can be placed.6 In Malawi’s largest healthcare facility, the Queen Elizabeth Central Hospital, suffering from a resourcepoor and staff depleted situation7 we frequently have to perform a percutaneous tracheostomy alone, dealing with tracheostomy and bronchoscopy at the same time. Alternatively we have to do the procedure without the help of a bronchoscope at all. Despite these difficulties, percutaneous tracheostomy remains an important tool to optimise the use of our precious ICU resources. When performed by the
intensivist, this means independence from the availability of a surgeon,8 as well as the advantage of early weaning from mechanical ventilation and thus earlier discharge from intensive care.1 This is extremely important because at any given moment there are several patients in our hospital in dire need of an intensive care bed.
1 Head of Department and Associate Professor, Department of Anaesthesia and Intensive Care, College of Medicine, University of Malawi, Malawi 2 Deputy Head of Department and Consultant, Department of Anaesthesia and Intensive Care, University of Malawi, Malawi 3 Lead Consultant in Intensive Care, Department of Anaesthesia and Intensive Care, University of Malawi, Malawi
Corresponding author: Gregor Pollach, Associate Professor, University of Malawi, Department of Anaesthesia and Intensive Care Blantyre 3, Chichiri, Blantyre, PO Box 360, Malawi, Africa. Email: [email protected]
Downloaded from tdo.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 24, 2015
Pollach et al.
215
Using the ‘Malawi device’ The challenge There are a number of recognised risks for the patient undergoing tracheostomy, namely injuries to the trachea, bleeding or infection.9,10 A highly hazardous scenario, arising if the tracheal tube is prematurely displaced before the airway is secured via the tracheostomy, results in ‘can’t intubate, can’t ventilate’. An inexperienced assistant (when available) may readily withdraw the tracheal tube too far while trying to make space for the insertion of the tracheostomy. This leaves the operator in the difficult position of having urgently to reestablish the airway either by endo-tracheal intubation or rapid tracheal dilatation. The first means re-scrubbing, and the second is fraught with danger. In our setting it is uncommon to have one experienced anaesthetist available, let alone two. Consequently, the one performing the tracheostomy has to struggle to effect an immediate re-intubation of a non-ventilated patient, who has a half-done tracheostomy.
The solution In order to help this colleague and to deal with this situation we have constructed a simple and cheap device: the ‘Malawi device’. This is available in a prepared kit at the bedside so that it is available for immediate use if required during percutaneous tracheostomy. In the following paragraphs we use as an example the Ciaglia type of tracheostomy. In principle, our idea is applicable to different types of percutaneous tracheostomy sets. If another system, e.g. the ‘twisting dilatation’5 is used, it must be adjusted before its first use. This is not difficult and would mean connecting the dilation device to a ventilation tube for example, instead of an endotracheal tube with the Ambu bag.
Description of the device The device permits emergency ventilation through the dilator in the event that the airway is lost during the early stages of the percutaneous tracheostomy (Figure 1). It consists of a re-sterilised dilator of the size F 21, a shortened tracheal tube size 6.0 (which fits snugly over the F 21 dilator, owing to the flexibility of the material and so ensuring no air leak), a 90 swivel connector with a plug to close the Bronchoscopy port, a curved re-sterilised guide wire and an Ambu bag. The whole set costs less than E1; the self-inflating bag is available in any anaesthesia department. At first glance our set may seem a little complicated and cumbersome, but it is not. It is slim, lightweight, easy to assemble and simple to clean, and it can be assembled with a maximum length of around 50 cm.
The index case. A 48-year-old man was ventilated after he sustained a head injury 3 weeks previously. Weaning was difficult and three extubations failed despite a quite low pressure support and the ability of the patient to survive several hours on a T-piece with 40% oxygen. The patient was known to be difficult to intubate and there was only one anaesthesiologist in the department at that time. The anaesthetic clinical officers were not trained to perform a bronchoscopy on their own. Nevertheless, our ICU, which caters for a 1400-bed hospital with only four to five beds, was full. Referral to another centre was not possible and two young mothers were in dire need of an ICU bed due to peripartum sepsis. The only possibility of admitting at least one of the women was to fashion a tracheostomy on the aforementioned patient and continue his further management in a High Dependency Unit. Unfortunately no experienced surgeon was available to help with a tracheostomy. The anaesthesiologist performed a bronchoscopy on the patient and then started the percutaneous tracheostomy. Owing to the inexperience of the anaesthetic clinical officer responsible for the airway, the endo-tracheal tube was dislodged with the bronchoscope shortly after the percutaneous guide wire was introduced and the first dilations were done. The anaesthesiologist was confronted with an unventilated patient, known to be difficult to intubate, with a dilator in his trachea. The anaesthesiologist followed the prepared plan as described in the text, started to ventilate the patient, and when that proved successful, handed over surveillance of ventilation to the anaesthetic clinical officer. The patient was subsequently re-intubated not without difficulty. The percutaneous tracheostomy could then be re-commenced (Figure 2). Following this episode, it was decided to establish a backup for the lonely anaesthesiologist doing a percutaneous tracheostomy in these less than optimal conditions.
The procedure If the orotracheal airway is lost during the procedure, the device can rapidly be assembled from the pre-prepared and sterilised kit by an assistant. If the Seldinger wire is still located in the trachea and can be seen coming through the dilator, the additional one from the kit can be spared. The shortened tube size 6.0 is advanced over the Seldinger wire and then placed over the dilator size F 21 until it engages with the proximal end of the dilator so as to produce a tight fit. The swivel angle piece adaptor is attached to the 15 mm connector on the 6.0 mm tube allowing the Seldinger wire to protrude from the bronchoscopy port.
Downloaded from tdo.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 24, 2015
216
Tropical Doctor 44(4)
Figure 1. (a) The parts of the ‘Malawi device’: the dilator, the tracheal tube, the swivel connector with opening and plug, the guide wire and the Ambu bag (a paediatric Ambu bag is shown for better visibility in the picture). (b) An important detail – the guide wire fits through the swivel connector and can be fixed through the plug. (c) The set with five ingredient parts, which need to be connected together.
The plug can be inserted into the port both to immobilize the Seldinger wire and produce an airtight seal, allowing manual ventilation via the device using a selfinflating bag. The 6.0 tube connects with the 15 mm connector to the swivel connector via a Seldinger wire which measures approximately 45 cm. Lastly the Ambu bag with oxygen is attached and ventilation can commence. Although the tube and dilator are partially obstructed by the Seldinger wire, oxygenation and adequate ventilation can usually be achieved. Nevertheless the effectiveness of this method must be tested with the particular model of percutaneous tracheostomy available before using the ‘Malawi device’ for the first time on a patient. Once oxygenation of the patient is secure, an assistant can then take over manual ventilation using the self-inflating bag, while the operator can deal with reintubation in a controlled manner.
The diameter of the narrowest point is not specified by the manufacturer. Depending on the size of the Seldinger wire ventilation is possible with a lumen which measures the size of G 12 (purely for the air flow, excluding the Seldinger wire, which is larger than the G 14 size which is in use in emergencies to puncture the cricoid and proceed with jet-ventilation). The G 12 opening can be enlarged when preparing the kit with a very thin Seldinger wire. With this method a tidal volume of 300–400 mL can be achieved. When using 100% oxygen, this is sufficient for oxygenation. Carbon dioxide elimination occurs in the normal way back through trachea. Pressures were actually difficult to measure because ventilation was performed manually with an Ambu bag (and the pressure at the end of the needle does not represent the true ventilation pressure in the bronchi). The creation of a side-hole in the dilator, as suggested in the discussion, greatly improves ventilation parameters.
Downloaded from tdo.sagepub.com at Kungl Tekniska Hogskolan / Royal Institute of Technology on July 24, 2015
Pollach et al.
217 Taking out the Seldinger wire is not an option either because then the dilator would slip out of the trachea, considering already the short length the dilator lies in the tracheal lumen. The consequence would be to lose the airway during the manipulations necessary to ventilate the patient. The ‘Malawi device’ overcomes the problem of the presence of the long Seldinger wire, which would otherwise prevent the connection of airway equipment, by allowing the end to leave via the bronchoscopy port of the angle piece where it is anchored by insertion of the sealing plug. The sealing plug prevents migration of the wire and produces an airtight seal. Our solution demonstrates several advantages:
Figure 2. The fully assembled device ready for emergency ventilation. (Registrars were able to assemble it at the mannequin in
