Current evidence for the use of Ventilator Hyperinflation to aid secretion clearance and improve lung compliance in mechanically ventilated adult patients.
Date First Published:
June 8, 2018
Last Updated:
July 18, 2018
Report by:
Olivia Chapman, Senior Physiotherapist (University College Hospital)
Three-Part Question:
What is the current evidence for the [use of Ventilator Hyperinflation (VHI)] to [aid secretion clearance and improve lung compliance] in [mechanically ventilated adult patients]?
Clinical Scenario:
A 62-year-old male is admitted to the intensive care unit with sepsis and is intubated and mechanically ventilated. He develops a moderate secretion load with reduced lung volumes and requires respiratory physiotherapy. You wonder if there is evidence to support the use of VHI to aid secretion clearance and improve lung compliance in this case.
Search Strategy:
Cochrane, PubMed, Physiotherapy evidence database (PEDro) and NICE databases were searched using the term: ‘Ventilator Hyperinflation’.
Search Details:
Cochrane Library: 55 results, 6 relevant, 1 excluded as full text not available: 5 relevant
Pubmed: 239 results, 8 relevant, 1 excluded as not available in English: 7 relevant
PEDro: 52 results: 1 relevant
NICE: No results
Hand searching: Nil new relevant
After duplicates removed: 8 relevant
Pubmed: 239 results, 8 relevant, 1 excluded as not available in English: 7 relevant
PEDro: 52 results: 1 relevant
NICE: No results
Hand searching: Nil new relevant
After duplicates removed: 8 relevant
Outcome:
346 hits, 8 papers relevant.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Do Commonly Used Ventilator Settings for Mechanically Ventilated Adults Have the Potential to Embed Secretions or Promote Clearance? G. Ntoumenopoulos and E. Main 2011 United Kingdom | 20 intubated and ventilated adult patients. | Observational study. | Small sample size. Short ventilation observation period. No information on presence of airway secretions. Did not assess changes in PIF:PEF bias with changes in ventilator. |
||
| Ventilator hyperinflation: A survey of current physiotherapy practice in Australia and New Zealand K Hayes et al 2011 Australia and New Zealand | Senior physiotherapists working in ICU in Australia or New Zealand | Postal Survey | Not applicable – survey of current clinical practice amongst senior physiotherapists | 21% used VHI in practice. | Only requested one response per ICU. Further studies are required to define optimal parameters and promote standardised delivery. |
| Main barriers cited: lack of training and lack of medical approval. | |||||
| 91% of respondents used Manual Hyperinflation (MHI). | |||||
| Most commonly cited indication for VHI was sputum retention. | |||||
| Almost half of respondents used VHI did not have a protocol. | |||||
| A comparison of the effects of manual and ventilator hyperinflation on static lung compliance and sputum production in intubated and ventilated intensive care unit patients S. Berney and L Denehy 2002 Australia | 20 intubated and ventilated adult patients | MHI versus VHI in prospective, randomised, controlled crossover study | Sputum wet weight | No significant difference between the sputum production in either technique. | This is the first study to look at the effects of VHI on static lung compliance so results cannot be compared. |
| Static compliance | Both VHI and MHI significantly improved static lung compliance | ||||
| Comparison of the effectiveness of manual and ventilator hyperinflation at different levels of positive end expiratory pressure in intubated and ventilated intensive care unit patients C. Savian, J Paratx and A. Davies 2006 Australia | 14 intubated and ventilated adult patients | MHI versus VHI in single blind randomised crossover study. |
Sputum wet weight | No significant difference in: sputum production, improvements in pO2:Fio2, or levels of PEEP between the two techniques. | Arterial blood gases 30 minutes after treatment could not be obtained for ethical reasons. Patient group did not have a large secretion load. |
| Peak expiratory flow rate (PEFR) | Trend towards a lower PEF in patients on a PEEP of 10 using VHI. | ||||
| Static compliance | VHI improved static respiratory system compliance. | ||||
| Oxygenation | |||||
| Mean arterial pressure (MAP) and Heart Rate (HR) | |||||
| PaCO2 | |||||
| Ventilator versus manual hyperinflation in clearing sputum in ventilated intensive care unit patients D Dennis et al 2012 Australia | 48 intubated and ventilated adult patients who had atelectasis or consolidation on chest X Ray. | MHI versus VHI in crossover trial |
Sputum wet weight | No significant difference in sputum cleared between MHI and VHI. | Future studies needed to explore physiotherapy techniques combined with VHI for recruitment. |
| MHI resulted in a higher peak airway pressure | |||||
| No significant difference in measures of gas exchange, respiratory and hemodynamic status. | |||||
| Comparison of effects of manual versus ventilator hyperinflation on respiratory compliance and arterial blood gases in patients undergoing mitral valve replacement F Ahmed et al 2010 India | 30 post-operative patients, who had undergone mitral valve replacement for rheumatic heart disease. | MHI vs VHI in paralysed patients. Randomised, 2 group intervention study |
Static compliance | VHI is as effective as MHI in improving pulmonary compliance. | Oesophageal balloon was not used in the measurement of compliance. Both methods were volume dependent. Specific brand of MHI bag used. Clinical significance on patient outcomes are unclear, further research is needed. |
| Dynamic compliance | VHI maintained improvements in static lung compliance above baseline for a longer duration compared to MHI. | ||||
| Oxygenation | Improved Pa02:Fi02 ratio in MHI. | ||||
| pH | |||||
| paCO2 | |||||
| Effects of ventilator vs manual hyperinflation in adults receiving mechanical ventilation: a systematic review of randomised clinical trials A Anderson et al 2015 United Kingdom | 4 Randomised Controlled Trials | MHI versus VHI: Systematic Review |
Sputum wet weight | 3 studies found no difference in sputum weight. | Publication Bias. Only included studies from a 20-year period. Lack of long term follow up (past 30 minutes) in all four studies. Co-intervention bias |
| Dynamic and static pulmonary compliance | 3 studies found no significant difference in static lung compliance. | ||||
| Oxygenation | Nil reported adverse events. | ||||
| Cardiovascular stability | |||||
| Hyperinflation using pressure support ventilation improves secretion clearance and respiratory mechanics in ventilated patients with pulmonary infection: a randomised crossover trial D Lemes et al 2009 Brazil | 30 mechanically ventilated patients with pulmonary infection. | VHI in side lying versus side-lying alone in randomised crossover trial |
Sputum volume | VHI more efficient in secretion clearance.VHI more efficient in secretion clearance. | Assessor not blinded. Clinically relevant outcomes were not considered. Different VHI protocols should be compared to establish most advantageous procedure. |
| Static compliance | Respiratory compliance increased in VHI group. | ||||
| Total resistance of respiratory system | No significant difference in the change in respiratory resistance between the two interventions. | ||||
| No adverse effects noted in either group | |||||
| Do Commonly used ventilator Settings for Mechanically Ventilated Adults have the potential to embed secretions or promote clearance? G. Ntoumenopoulos and E. Main 2011 United Kingdom | 20 intubated and ventilated adult patients. | Observational | Peak inspiratory flow (PIF) and peak expiratory flow (PEF) on baseline vPeak inspiratory flow (PIF) and peak expiratory flow (PEF) on baseline ventilation settings. entilation settings. | At baseline settings, all patients had an inspiratory flow bias. | Small sample size. Short ventilation observation period. No information on presence of airway secretions. Did not assess changes in PIF:PEF bias with changes in ventilator. |
Author Commentary:
The current evidence base for VHI is poor. High quality randomised controlled trials are needed to allow for standardised guidelines to be set for clinical practice.
Bottom Line:
Current evidence shows that Ventilator Hyperinflation has similar effects to Manual Hyperinflation in secretion clearance, however is used less frequently in practice. The evidence also demonstrates there are similar improvements in lung compliance indicated by improved lung volumes post treatment using Ventilator Hyperinflation and Manual Hyperinflation. This conclusion is based on limited evidence base and further clinical studies are needed.
References:
- G. Ntoumenopoulos and E. Main . Do Commonly Used Ventilator Settings for Mechanically Ventilated Adults Have the Potential to Embed Secretions or Promote Clearance?
- K Hayes et al. Ventilator hyperinflation: A survey of current physiotherapy practice in Australia and New Zealand
- S. Berney and L Denehy. A comparison of the effects of manual and ventilator hyperinflation on static lung compliance and sputum production in intubated and ventilated intensive care unit patients
- C. Savian, J Paratx and A. Davies . Comparison of the effectiveness of manual and ventilator hyperinflation at different levels of positive end expiratory pressure in intubated and ventilated intensive care unit patients
- D Dennis et al . Ventilator versus manual hyperinflation in clearing sputum in ventilated intensive care unit patients
- F Ahmed et al . Comparison of effects of manual versus ventilator hyperinflation on respiratory compliance and arterial blood gases in patients undergoing mitral valve replacement
- A Anderson et al . Effects of ventilator vs manual hyperinflation in adults receiving mechanical ventilation: a systematic review of randomised clinical trials
- D Lemes et al . Hyperinflation using pressure support ventilation improves secretion clearance and respiratory mechanics in ventilated patients with pulmonary infection: a randomised crossover trial
- G. Ntoumenopoulos and E. Main . Do Commonly used ventilator Settings for Mechanically Ventilated Adults have the potential to embed secretions or promote clearance?