Humidity Therapy for Spontaneously Breathing Tracheostomy Patients

Currently, there is no empirical evidence of the significant superior efficacy of particulate
water via large volume nebulizer (LVN), in providing humidity therapy to spontaneously
breathing tracheostomy patients over molecular water via heated humidifier. Large volume
nebulizers are a commonly used therapy in clinical practice for tracheostomy patients.
However, in terms of an optimal modality for providing humidification when the upper-airway
is bypassed, there is much controversy. Much of the available literature has looked into a
comparison between heated humidity (HH) and heat and moisture exchangers (HMEs) in intubated
patients in crossover studies and case studies. In addition, they have seen overall greater
outcomes in HH. Nonetheless, no recent studies have directly compared the use of HH and LVNs
during humidity therapy in spontaneously breathing tracheostomy patients. Although a couple
of past studies have directly compared the two humidity types in spontaneously breathing
patients with a bypassed upper airway, no research has been conducted as follow-up to these
past studies. Furthermore, these studies were restricted to outcomes of arterial oxygenation
and also had limitations due to the short duration of the studies and small sample sizes.

A tracheostomy is an artificial airway characterized by a surgically made incision that
passes through the anterior neck and into the trachea. A tube is placed inside the hole
created by the incision to provide a patent airway for an individual with impaired
respiratory function to breathe. Approximately 100,000 tracheostomy procedures are performed
annually in the United States. The burden of cost for tracheostomy patients in the United
States related to the duration of hospital stay for these patients is a major factor that has
contributed to the resurgence of interest in the management of tracheostomy patients.
According to data from the Agency for Healthcare Research and Quality (AHRQ), in 2009, the
average length of hospital stay for a tracheostomy patient was 29 days. In 2013, an analysis
of data on patients with acute respiratory failure from 90% of the non-profit academic
medical centers in the United States revealed high resource utilization and high morbidity
rates for tracheostomy patients. The analysis also revealed that tracheostomy patients with
acute respiratory failure had on average, a longer intensive care unit stay (24.3 days) than
non-tracheostomy patients with acute respiratory failure (6.6 days). Mean hospital stay was
also higher for tracheostomy patients (36.6 days) than non-tracheostomy patients (11.3 days).
Moreover, on average, the total hospital cost for tracheostomy patients was $285,509 and $
86,118 for non-tracheostomy patients.

Management of a tracheostomy is a complex undertaking and includes many components that span
several healthcare disciplines, including tube and stoma care, humidity therapy,
communication and swallowing strategies, emergency management, and weaning and decannulation.
In recent years, clinicians worldwide have demonstrated a renewed interest in the management
of tracheostomy patients due to recognition of preventable adverse outcomes for many of these
patients. The United Kingdom's 2014 report by the National Confidential Enquiry into Patient
Outcome and Death (NCEPOD) on the care received by tracheostomy patients concluded that
tracheostomy management is suboptimal. Since tracheostomy management is a complex,
multi-disciplinary endeavor, recent research has advocated the use of a multidisciplinary
tracheostomy team. One notable collective is the Global Tracheostomy Collaborative; this
collaboration consists of a multidisciplinary team of physicians, nurses, respiratory
therapists, speech therapists, and patients working together to find best practices and
improve the clinical outcomes centered on tracheostomy care. As part of their mission, they
state that, "through multidisciplinary care, a standardization of care, broad staff
educations, and patient and family involvement, these critical key drivers serve to continue
to bring about improvements in tracheostomy care." In an effort to improve the care of
tracheostomy patients, an expert panel convened by the American Academy of Otolaryngology -
Head and Neck Surgery developed a Clinical Consensus Statement on the management of these
patients. The authors of the consensus statement noted that current approaches to
tracheostomy care are inconsistent among clinicians and between different institutions.
Consequently, the primary goal of the consensus statement is to reduce variances in clinical
practice when managing tracheostomy patients, and minimizing complications. Aspects of
tracheostomy management that are addressed by the clinical consensus statement include
initial tube change, management of emergencies and complications, decannulation protocol,
management of tube cuffs and communication devices, and specific patient and caregiver needs.
With regard to humidification, the expert panel reached the following consensus: (i)
humidification should be used during the immediate postoperative period and as necessary
thereafter, (ii) humidification should be used if a patient requires mechanical ventilation,
and (iii) humidification should be used for patients with a history of thick secretions.

Inadequate humidification for tracheostomized patients can result in an assortment of adverse
complications, which ultimately negatively impact the epithelial integrity of the airway.
This is the case in situations where patients breathe the cold, dry air delivered by the gas
supply systems of hospitals. According to the American Association for Respiratory Care
(AARC) clinical practice guidelines for humidification, adequate humidification requirements
when the upper airway is bypassed entails a humidity output of 33-44 mg H2O/L, with a 100%
relative humidity at 34-41°C. Several types of devices may be used in the clinical setting to
provide humidity therapy. Thus, awareness of the type of humidity therapy they provide is
just as important as understanding their principles of operation, application, as well as
their potential hazards. The use of large volume jet nebulizers (LVNs) is very common in
respiratory care practice as a modality for humidification therapy. These devices are
pneumatically powered, and deliver cool/bland aerosol by using a variable oxygen diluter and
water passing through a jet nozzle. The aerosols provided by LVNs are usually unheated, cool
and bland. Thus, one would expect to see complications arise from the wide use of LVNs in the
clinical setting. However, superior efficacy of a device still remains questionable and as
evident, there exists huge inadequacies in studies on humidification of spontaneously
breathing tracheostomy patients and overall tracheostomy care. Heated humidifiers entail the
use of active humidity, which use energy and water external to the body (e.g. a wick
humidifier or passover humidifier) for conditioning inspired gases. Passive heated
humidifiers on the other hand, rely on body temperature and the humidity gradient between the
body and external environment. One of the most widely used types of passive humidifiers is
the heat and moisture exchanger (HME), which contains a condenser element designed to enhance
capturing the exhaled moisture (in the form of water vapor) from the patient's breath, then
transfer and release this moisture back into the inspired air on the next breath.

Kuo et al. compared bland aerosol and heated humidity in spontaneously breathing patients
with nasal endotracheal tubes and normal lungs and found a detrimental effect on patient's
oxygenation status when using a heated jet nebulizer for short-term use. It is interesting to
note that these effects were improved by exchanging therapy to heated humidity. However,
contradictory results were observed by Rozsasi et, al. in which tracheal humidity remained at
higher levels after use of particulate aerosol spray (300µL H2O/L air at 26°C, 90% relative
humidity) in comparison to molecular water vapor (32µL H2O/L air at 32°C, 100% relative
humidity). Studies have in addition compared the use of heat and moisture exchangers (HMEs),
a type of passive humidification, in comparison to HH in mechanically ventilated patients and
have shown mixed results regarding the superior efficacy of one over the other. However, a
recent systematic review found no difference in adverse clinical events such as artificial
airway occlusion, mortality, pneumonia, or respiratory complications between HH and HME.

The goal of the proposed study is to help bridge the knowledge gap regarding the management
of patients with tracheostomy tubes and to improve patient care by contributing to the
development of clinical practice guidelines relevant to humidity therapy for spontaneously
breathing tracheostomy patients.

Methodology Study Design and Population The proposed study will be conducted at Rush
University Medical Center (RUMC) in Chicago, Illinois. Using the medical center's electronic
medical database (Epic), a current list of tracheostomy patients will be acquired as the
accessible population. From this patient list, a sample of those that fit the inclusion and
exclusion criteria will be used as the study sample. Patients from the intensive care unit
(ICU) as well as various acute care floors will be included in the study. Participants will
be approached individually to request consent for participation in the proposed study, and
their cooperation will be emphasized as being strictly voluntary.

Consecutive sampling will be employed as the sampling technique to include every available
tracheostomy patient who meets the inclusion criteria, in order to attain results as close to
the target population of spontaneously breathing tracheostomy patients as possible. This is
the most robust nonprobability sampling strategy because since the complete accessible
population is studied, the chance of observing a representative subset of the population is
increased.

Using the design of a prospective randomized control trial (RCT), patients will be randomly
assigned to either of two groups: (A) humidity therapy with aerosol using a large volume
nebulizer, or (B) humidity therapy with molecular water vapor using heated humidity. A sample
size greater than 100 participants will be the target, as the proposed study intends to
address the small sample size limitations of previous studies. Furthermore, the study period
of approximately 60 days is desired to observe the long-term outcomes that may result.

Inclusion Criteria

- Greater than eighteen years old

- Tracheotomized less than or equal to two weeks before entry into the study

- Spontaneously breathing

Exclusion Criteria

- Less than eighteen years old

- Tracheotomy performed more than two weeks prior to enrolment in the study

- Mechanically ventilated