Tracheostomy Prevention and Alternatives
In the vast majority of cases endotracheal intubation precedes tracheostomy tube placement. The trach is generally opted for in the course of ventilation support when the patient is unable to be extubated within a period that varies from institution to institution and specialist to specialist but is usually from as quickly as 3 to as long as 30 days depending on the clinical situation and practice of the physician or institution. Endotracheal intubation carries a great many risks and complications similar to tracheostomy. It is an invasive, but not a surgically invasive procedure. Avoiding intubation is the most basic way to avoid a tracheostomy. In some cases every means to avoid intubation fail or where the patient’s rapidity and severity of deterioration prevent attempts at alternatives to intubation then intubation must be performed. When intubation is the only alternative, then successful extubation or removal of the endotracheal tube becomes the goal as soon as clinically safe and reasonable. Extubation readiness is achieved by decreasing, then eliminating the patient’s dependence on invasive ventilation. This is accomplished by medical support and time bringing about adequate improvement of the patient’s condition such that they may be sustained without invasive ventilator support and extubation can be accomplished successfully. Intubations should be avoided if possible and if not possible extubation should be given every possible chance of succeeding by employing non-invasive ventilation (NIV) modalities. This is the basic strategy for prevention of tracheostomy. The modalities that offer the greatest potential of either preventing intubation or supporting success post extubation are a triad that when utilized individually or in combination on a patient specific basis will offer the greatest chance of preventing tracheostomies. These interventions can be considered like the proverbial three legged stool. Efforts at avoiding tracheostomy are only maximized for all patients when skill with these interventions is developed, and attempts with these interventions either individually if successful individually or in combination are brought to bear. Tracheostomy, unless emergently placed generally should not be opted for until all efforts with the NIV triad have been attempted. There are advantages of each of the alternative forms of NIV. These modalities can be employed to potentially and ideally prevent intubation, facilitate weaning from invasive positive pressure ventilation, extubation and provide support during trach decannulation trials. Used aggressively towards these end points NIV interventions can greatly increase the chance of trach prevention.
NIV modalities that have shown good success in preventing intubation fall into three categories, Heated Humidified High Flow Nasal Cannula, Non-Invasive Positive Pressure Ventilation and Biphasic Cuirass Ventilation.
Endotracheal intubation will generally precede tracheostomy placement and may be avoided or terminated through individual or combined use of this triad of NIV techniques. We will therefore begin with a discussion of endotracheal intubation and follow with each of the NIV techniques in that triad.
If a patient requires ventilatory assistance which cannot be adequately managed with NIV interventions, typically physicians will move to invasive ventilation (endotracheal intubation). Due to the many well known side effects of invasive mechanical ventilation, all options should be exhausted to prevent the patient from requiring this level of support.
Once the patient is intubated, all efforts should be placed toward supporting resolution of the underlying illness and on removal of the endotracheal (ET) tube as quickly, while as safely, as possible. Many complications from intubation can arise, including but not limited to:
- Aspiration – Entry of material (such as secretions, food or drink, or stomach contents) from the mouth or other areas, into the airways. Consequences of pulmonary aspiration range from no injury at all, to pneumonia, to death within minutes from suffocation. This can happen in more than 3% of intubated patients (11).
- Esophageal intubation – While performing intubation, sometimes the placement of the tube can be incorrectly directed into the esophagus (to the stomach). Known as esophageal intubation, since the esophagus and stomach play no role in gas exchange this, obviously, leads to many problems, and in some situations may result in death within minutes if not immediately corrected.
- Injury – Placement of the tube can sometimes cause damage to the teeth, soft tissue at the back of the throat, or vocal cords, when difficulty is encountered or done incorrectly.
- Pneumothorax – Placement of the tube too deep can result in only one lung receiving ventilation and being over ventilated, which can result in a pneumothorax (collection of free air in the chest cavity that causes the lung to collapse) as well as inadequate ventilation.
- Toxic effects of lung over-inflation (volutrauma) include pneumothorax and acute lung injury
- Ventilator-associated pneumonia (VAP) develops at a rate of approximately 1% per day and has an attributable mortality rate as high as 20–50% (13).
- Cardiac output may be increased or decreased based on the preload- and afterload-reducing effects of positive pressure ventilation. Decreased cardiac output can have detrimental effects on the patient’s condition health.
Intubation should be taken very seriously. In situations where the patient or their loved ones are asked to decide for intubation a patient should fully understand the risks and complications involved in the placement of an endotracheal tube. In large part because prolonged intubation may lead to tracheostomy. , before intubation, it should be ensured that all other forms of NIV ventilation have been attempted and failed if at all possible and Once intubation has occurred these same techniques should be aggressively employed to remove the ET tube as soon as possible before trach is considered.
Face Mask Positive Airway Pressure or Non-Invasive Positive Pressure Ventilators (PAP or NIPPV)
This NIV technique utilizes a soft seal type of face mask. These masks are made in one of a multitude of configurations designed to maximize patient comfort and facial seal. The mask is connected to a ventilatory support device such as standard ventilator set to provide non-invasive support or a device specifically designed to provide non-invasive support called a BiPhasic Positive Airway Pressure (BiPAP) device. The mask is connected to the support device via a length of tubing and strapped to the patient’s face either over the nose or mouth and nose. These devices provide a pulmonary support intervention that is in general referred to as PAP for Positive Airway Pressure or NIPPV for Non-invasive Positive Pressure Ventilation. Their function includes the ability to assist with breathing by providing positive pressure on inhalation to help patients with larger breaths and can control breathing and increase total ventilation by increasing rate as well as depth of breaths. They can also provide supplemental levels of oxygen along with the support of breathing. NIPPV has been used successfully for preventing intubation in many patients. It has known drawbacks some of which can be overcome with use combined with one of the other NIV interventions.
Non-invasive mask ventilation candidates typically include the following patients:
- Nose, mouth, and upper airway are intact and free of defects that would interfere with ventilation by mask
- Ventilation is less than 24 hours per day, intermittent, or short-term
- Patient has a mild to moderate need for ventilatory support
- Patient has a low risk for aspiration
- Patient is adequately alert, able and willing to keep a mask on the face
Non-invasive mask ventilation can be attempted for patients who meet the above criteria in order to prevent the need for intubation and following extubation to enhance success and prevent tracheotomy surgery.
- Although regarded as a safer and much less invasive means of support than invasive ventilation, non-invasive face-mask ventilation still has concerns and precautions which much be observed:
- Claustrophobia can be a great concern for some patients whom cannot tolerate a face mask.
- Claustrophobia involves the inability to begin or continually use mask ventilation, which can occur in 5% to 20% of patients.(8)Misshaped facial structure can make finding a mask that does not leak very difficult
- Facial features such as a deviated septum can make breathing exclusively through the nose very difficult.
- Ventilation with a face mask may worsen sinus problems or cause severe abdominal distension (swelling of abdomen), as seen in up to 16% of patient side effects (9).
- Facial weakness reduces necessary jaw closure and ability to use a mouthpiece.
- Patients may not comply with usage because of discomfort
- For patients with significant pulmonary secretions NIPPV may prevent cough and clearance of the airways during use
- Oral intake of nutrition difficult or impossible during use
- Masks applied with inadequate humidification will result in thick oral and pulmonary secretions that can lead to airway blockages
- Patients may experience facial ulcers at pressure points under the mask which can preclude use
- Prolonged use in growing pediatric patients may create alteration in facial bone structure
- Gas flow from leaks at the nasal bridge area passing over the eyes can cause significant drying and discomfort
1/3 of NIPPV failure is due to mask intolerance
NIPPV or PAP has been use successfully as a means to prevent intubation, as a tool to prevent reintubation for patients that have difficulty following extubation. PAP devices have also been combined successfully with BCV increasing the potential of being able to avoid tracheostomy.
Until a trial of NIPPV has been attempted and allowed an opportunity to prevent intubation or re-intubation either alone or combined with BCV criteria for non-emergent tracheostomy is not fully met.
Heated and Humidified High Flow Nasal Cannula
Although grouped here with other techniques which support of ventilation by directly increasing air movement in and out of the lungs. he HHNC does not directly augment ventilation. The potential benefits can improve gas exchange and work of breathing indicators and has been documented to benefit in preventing intubation, increasing chances of success in the post extubation phase and as a tool to facilitate decannulation. Nasal oxygen administration with the standard cannula is limited as to flows applied depending on institutional policy at 6 up to 15 liters per minute (lpm). This limitation is due to the drying effect of the oxygen. Even with the standard bubble humidifier the oxygen is delivered with a humidity deficit when inhaled and brought to body temperature. This results in a drying effect to the mucosa with resultant discomfort and complications. When oxygen is conditioned to 100% humidified at or near body temperature there is no humidity deficit and the previously dry gas can be delivered via a nasal cannula at much higher flows without the complications and due to the high humidity and flows with therapeutic effects. These therapeutic effects include:
- Thinning effect on pulmonary secretions enhancing mucocilliary clearance
- A very consistent delivery of the required oxygen mixture to the lungs by nearly meeting or exceeding the patient’s inspiratory flow. There is very little room air admixture into the delivered gas thus
- fraction of inspired O2 does not vary significantly
- The high flow creates a washout effect on the anatomical dead space thus potentially clearing more CO2 without greater respiratory effort required
- The high flows can generate a slight positive airway pressure that provides an airway opening, lung recruitment and work of breathing benefit
HHNC has been used with success as a means to prevent intubation, to enhance success post extubation and to assist with decannulation trials. Lung recruitment and secretion modification benefits may last for a period beyond use. Although HHNC does not provide direct support of increased alveolar minute ventilation potential for improved CO2 clearance can be a benefit. In cases where increase alveolar minute ventilation is required, greater recruitment effect or attenuation of elevated work of breathing is needed, HHNC can readily be combined with BCV for an effect superior to what either therapy alone can provide.
Until a trial of HFNC has been attempted and allowed an opportunity to prevent intubation or re-intubation either alone or combined with BCV criteria for non-emergent tracheostomy is not fully met.
Biphasic Cuirass Ventilation
Biphasic Cuirass Ventilation (BCV) combines a cuirass (chest shell) and flexible foam seal that covers the chest and upper abdomen with a power unit. The power unit connects with the cuirass via a pressure delivery hose and a pressure sensing tube. BCV works very similarly to the way the body creates respirations naturally.
The cuirass creates an air chamber over the chest and abdomen while the power unit controls the pressure within the cuirass. This affects the dimensions of the thoracic cavity and thus inflation and deflation of the lungs. Inhalation occurs due to the power unit creating a negative pressure within the cuirass. Inspiration with the RTX is supported by natural expansion of the chest wall and descent of the diaphragm. The resulting negative pressure gradient pulls gas into compromised alveoli as well as healthy ones. This natural support of lung inflation in comparison to positive pressure ventilation results in:
- Better distribution of tidal volumes
- Little or no chance of alveolar over distension as volume exchange is distributed across a larger portion of the lungs
- A lung protective effect due to improved compliance with negative lung inflation and better volume exchange for less trans-pulmonary pressure difference.
In modes that provide ventilation, the power unit will switch the pressure in the cuirass from negative to positive. This active positive expiratory phase creates the opposite effect on the thorax facilitating lung deflation. This unique feature will decrease the patient’s work of breathing by mimicking the active use of expiratory accessory muscles and increasing minute ventilation of an individual experiencing cardiopulmonary illness.
BCV provides a safe means of lung recruitment. It can increase minute ventilation, and can function as a secretion clearance device with assisted cough. Many of the benefits of BCV will persist for some time following use. In some cases use of only short periods at intervals provides significant results. These capabilities enable the RTX to benefit many patients with cardio-pulmonary compromise and respiratory distress. It produces effective ventilation in both normal and injured lungs, in clinical conditions marked by increases in pulmonary shunt and/or increased dead space ventilation. BCV has been demonstrated to improve oxygenation, CO2 clearance, cardiac output and organ system perfusion. When combined with PPV it can help lower mean intrathoracic pressures and lessen potential side effects of PPV. It can be used adjunctively with all modes of positive pressure ventilation (PPV), NIPPV and HHNC to improve ventilation, offering a means of avoiding intubation, facilitating ventilator weaning. BCV can assisting the PPV weaning process from even prior to extubation since BCV can be used in conjunction with PPV and as a tool to enhance potential for successful extubation.
BCV due to the fact that the patient’s face is not covered as with NIPPV may be better tolerated and accepted. Negative lung inflation used by BCV creates a different lung inflation pattern than positive pressure resulting in a greater number of gas exchange units being brought into function throughout the respiratory cycle.
BCV has been found useful in patients with multiple forms of respiratory compromise and can be used in most cases where PPV or NIPPV would be considered.
Until a trial of BCV has been attempted and allowed an opportunity to prevent intubation or re-intubation either alone or combined with HFNC or NIPPV criteria for non-emergent tracheostomy is not fully met.
If determined that a patient will require ventilatory support long term while intubated, a trach may be considered, but all options to prevent the patient needing the tracheostomy have not been exhausted until ventilator weaning is attempted using HFNC, NIPPV and or BCV to assist the weaning process and as a means to meet the patient’s ongoing needs for support non-invasively. Use of these methods offers a greater likelihood that the ET tube can be successfully removed and a trach procedure prevented. Until a trial of the use of this triad or tracheostomy preventing interventions have been attempted and allowed an opportunity to prevent intubation or re-intubation either alone or combined criteria for non-emergent tracheostomy is not fully met.rgent tracheostomy is not fully met.