Trial Outcomes & Findings for Comparison of Airway Clearance Therapy in Cystic Fibrosis Using the Same VEST Therapy Device But With Different Settings (NCT NCT00685035)
NCT ID: NCT00685035
Last Updated: 2016-07-25
Results Overview
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
Recruitment status
COMPLETED
Study phase
PHASE4
Target enrollment
17 participants
Primary outcome timeframe
Produced during each airway clearance therapy session on days 1 and 4
Results posted on
2016-07-25
Participant Flow
Potentially eligible patients were identified by query of the Minnesota CF database based on age and FEV1. This list was then reviewed and patients who met additional eligibility requirements were contacted by phone or recruited during a clinic visit by one of the study investigators. Enrollment was completed between 6/1/08 and 10/31/08.
Participant milestones
| Measure |
Higher Pressure/Variable-freq, Then Lower Pressure/Mid-freq
HFCWC therapy first with a higher pressure/variable frequency protocol (1st Intervention). After a washout period of 2 days, this group subsequently crossed-over to the lower-pressure/mid-frequency HFCWC protocol (2nd Intervention).
|
Lower Pressure/Mid-freq, Then Higher Pressure/Variable-freq
HFCWC therapy first with a lower pressure/mid-frequency protocol (1st Intervention). After a washout period of 2 days, this group subsequently crossed-over to the higher-pressure/variable frequency HFCWC protocol (2nd Intervention).
|
|---|---|---|
|
Period 1: First Intervention: 30 Minutes
STARTED
|
9
|
8
|
|
Period 1: First Intervention: 30 Minutes
COMPLETED
|
8
|
8
|
|
Period 1: First Intervention: 30 Minutes
NOT COMPLETED
|
1
|
0
|
|
Period 2: 2-day Washout
STARTED
|
8
|
8
|
|
Period 2: 2-day Washout
COMPLETED
|
8
|
8
|
|
Period 2: 2-day Washout
NOT COMPLETED
|
0
|
0
|
|
Period 3: 2nd Intervention
STARTED
|
8
|
8
|
|
Period 3: 2nd Intervention
COMPLETED
|
8
|
8
|
|
Period 3: 2nd Intervention
NOT COMPLETED
|
0
|
0
|
Reasons for withdrawal
| Measure |
Higher Pressure/Variable-freq, Then Lower Pressure/Mid-freq
HFCWC therapy first with a higher pressure/variable frequency protocol (1st Intervention). After a washout period of 2 days, this group subsequently crossed-over to the lower-pressure/mid-frequency HFCWC protocol (2nd Intervention).
|
Lower Pressure/Mid-freq, Then Higher Pressure/Variable-freq
HFCWC therapy first with a lower pressure/mid-frequency protocol (1st Intervention). After a washout period of 2 days, this group subsequently crossed-over to the higher-pressure/variable frequency HFCWC protocol (2nd Intervention).
|
|---|---|---|
|
Period 1: First Intervention: 30 Minutes
Pulmonary lab plethysmography malfunctio
|
1
|
0
|
Baseline Characteristics
Comparison of Airway Clearance Therapy in Cystic Fibrosis Using the Same VEST Therapy Device But With Different Settings
Baseline characteristics by cohort
| Measure |
All Study Participants
n=17 Participants
Half patients randomly assigned to HFCWC therapy first with a higher-pressure/variable frequency protocol. This entailed performing a 30 minute session with pressure of 10 and 5 minutes each at frequencies of 8,9, and 10 Hz followed by pressure of 6 and 5 minutes each at frequencies of 18, 19, and 20 Hz. This group subsequently crossed-over to the lower-pressure/mid-frequency HFCWC protocol after a washout period of 2 days. This entailed performing a HFCWC session using a pressure of 5 and frequency of 12 Hz for the entire 30 minute session. The other half of subjects were randomly assigned to perform the lower-pressure/mid-frequency protocol first followed by the higher pressure/mixed-frequency after the 2 day washout period
VEST Airway Clearance System, Model 205 : Subjects will perform pulmonary function tests prior to and following each airway clearance therapy. All sputum produced during, and for 15 minutes following airway clearance therapy will be collected. Subjects
|
|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=5 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
17 Participants
n=5 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=5 Participants
|
|
Age, Continuous
|
33.3 years
STANDARD_DEVIATION 7.3 • n=5 Participants
|
|
Sex: Female, Male
Female
|
7 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
10 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
17 participants
n=5 Participants
|
PRIMARY outcome
Timeframe: Produced during each airway clearance therapy session on days 1 and 4Population: In a previous study with similar design,21 the standard deviation for the difference in the mean sputum wet weight between treatment arms was 4.6 g. Assuming the same standard deviation for the current study, enrollment of 16 subjects provided an 80% chance of detecting a 3.5-g difference in the sputum wet weights at a significance level of .05.
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
Outcome measures
| Measure |
Sputum Wet Weight Higher Pressure/Variable Frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Wet Weight Lower Pressure/Mid-frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Dry Weight Higher Pressure/Variable Frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
Sputum Dry Weight Lower Pressure/Mid-frequency
n=15 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
G" Loss Modulus 1 Rad/Sec Higher Pressure/Variable Frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 1 Rad/Sec Lower Pressure/Mid-frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Higher Pressure/Variable Frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Lower Pressure/Mid-frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
|---|---|---|---|---|---|---|---|---|
|
Sputum Wet and Dry Weight
|
6.4 grams
Interval 0.49 to 22.0
|
4.8 grams
Interval 0.24 to 15.0
|
0.20 grams
Interval 0.009 to 0.62
|
0.12 grams
Interval 0.0001 to 1.0
|
—
|
—
|
—
|
—
|
SECONDARY outcome
Timeframe: Prior to and following each airway clearance therapy session on days 1 and 4Population: Power calculation not performed for secondary outcomes.
Spirometry was performed prior to, and immediately following, all HCWC sessions on Day 1. Spirometry was performed immediately prior to, and immediately following, all HFCWC sessions on Day 4. Spirometry was performed according to American Thoracic Society/European Respiratory Society standards.
Outcome measures
| Measure |
Sputum Wet Weight Higher Pressure/Variable Frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Wet Weight Lower Pressure/Mid-frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Dry Weight Higher Pressure/Variable Frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
Sputum Dry Weight Lower Pressure/Mid-frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
G" Loss Modulus 1 Rad/Sec Higher Pressure/Variable Frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 1 Rad/Sec Lower Pressure/Mid-frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Higher Pressure/Variable Frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Lower Pressure/Mid-frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
|---|---|---|---|---|---|---|---|---|
|
Pre vs. Post Therapy Spirometry
|
70 ml
Standard Deviation 90
|
90 ml
Standard Deviation 120
|
80 ml
Standard Deviation 160
|
80 ml
Standard Deviation 230
|
—
|
—
|
—
|
—
|
SECONDARY outcome
Timeframe: Sputum produced during the 15 minutes immediately following airway clearance therapy sessions on day 1 and day 4Population: power calculation not performed for secondary outcomes
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
Outcome measures
| Measure |
Sputum Wet Weight Higher Pressure/Variable Frequency
n=12 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Wet Weight Lower Pressure/Mid-frequency
n=12 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Dry Weight Higher Pressure/Variable Frequency
n=12 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
Sputum Dry Weight Lower Pressure/Mid-frequency
n=12 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
G" Loss Modulus 1 Rad/Sec Higher Pressure/Variable Frequency
n=12 Participants
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 1 Rad/Sec Lower Pressure/Mid-frequency
n=12 Participants
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Higher Pressure/Variable Frequency
n=12 Participants
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Lower Pressure/Mid-frequency
n=12 Participants
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
|---|---|---|---|---|---|---|---|---|
|
Rheology and in Vitro Cough Transportability of Sputum Produced Immediately Following Airway Clearance Therapy Session
|
4.43 dynes/cm^2
Interval 0.0 to 162.0
|
4.61 dynes/cm^2
Interval 0.0 to 119.0
|
107.3 dynes/cm^2
Interval 11.2 to
|
130.7 dynes/cm^2
Interval 34.0 to
|
10.7 dynes/cm^2
Interval 0.4 to 205.0
|
7.4 dynes/cm^2
Interval 0.93 to 144.0
|
1,224 dynes/cm^2
Interval 383.0 to
|
862 dynes/cm^2
Interval 0.0 to
|
SECONDARY outcome
Timeframe: Immediately following each airway clearance therapy on day 1 and day 4Population: power calculation not performed for secondary outcomes
Following each HFCWC session on day 1 and day 4, subjects completed a questionnaire that rated the comfort and efficacy of each HFCWC session using a 5-point scale. The questionnaire was entitled "Post-Therapy Questionnaire". Scale range for comfort ranged from 1 (very uncomfortable) to 3 (neutral) to 5 (very comfortable). Scale range for how "effective" the HFCWC session was ranged from 1 (minimally effective) to 3 (neutral) to 5 (very effective).
Outcome measures
| Measure |
Sputum Wet Weight Higher Pressure/Variable Frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Wet Weight Lower Pressure/Mid-frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The sputum "wet weight" was calculated after re-weighing the container with the sputum pellet.
|
Sputum Dry Weight Higher Pressure/Variable Frequency
n=16 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
Sputum Dry Weight Lower Pressure/Mid-frequency
n=12 Participants
All sputum expectorated during all HFCWC sessions was collected in a pre-weighed specimen container and immediately sealed. Half the subjects used higher pressure/mixed frequency on day 1 followed by lower pressure/mid-frequency on day 4. Half the patients performed lower pressure/mid-frequency on day 1 followed by higher pressure/mixed frequency on day 4. All specimens were immediately centrifuged at 21,150 g for 15 min at 4°C, and the supernatant was completely removed to eliminate saliva. The container was then left open in an oven with the temperature set at 65°C for a minimum of 3 days to allow for complete desiccation. The sputum "dry weight" was calculated after re-weighing the container.
|
G" Loss Modulus 1 Rad/Sec Higher Pressure/Variable Frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 1 Rad/Sec Lower Pressure/Mid-frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Higher Pressure/Variable Frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
G" Loss Modulus 100 Rad/Sec Lower Pressure/Mid-frequency
Sputum was collected during the 15 minutes immediately following HFCWC sessions on day 1 and day 4. Half the subjects performed higher-pressure/mixed frequency HFCWC on Day 1 followed by lower pressure/mid-frequency HFCWC on Day 4. The other half of subjects performed lower pressure/mid-frequency on Day 1 followed by higer pressure/mixed-frequency on Day 4. Samples were studied with a rheometer (AR1000, TA Instruments, New Castle, Delaware) to assess the dynamic frequency range of stress-strain of a 20 microliter sputum sample over driving frequencies of 1-100 rad/s. Shear storage modulus (G') and shear loss modulus (G") were determined from these curves after nondestructive creep transformation. G' (or dynamic elasticity) measures stored energy and is a property of ideal solids. G" is directly proportional to viscosity (viscosity x frequency) and is a property of ideal liquids.
|
|---|---|---|---|---|---|---|---|---|
|
Patients' Perceived Comfort Using the Different Settings for the Vest Device
|
4.5 units on a scale
Interval 1.0 to 5.0
|
5 units on a scale
Interval 1.0 to 5.0
|
4 units on a scale
Interval 3.0 to 5.0
|
4 units on a scale
Interval 3.0 to 5.0
|
—
|
—
|
—
|
—
|
Adverse Events
Lower Pressure/Mid-frequency
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Higher Pressure/Variable Frequency
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Dr. Robert Kempainen
University of Minnesota School of Medicine
Phone: 612-873-6413
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place