Ventilator hyperinflation determined by peak airway pressure delivered: A randomized crossover trial.

AIM: The aim of this study was to see if a more sophisticated ventilator hyperinflation protocol might result in more sputum clearance compared to manual hyperinflation. BACKGROUND: Hyperinflation has been used to mobilize lung secretions in mechanically ventilated patients in the intensive care unit setting for almost 50 years. In the past decade, rather than using a bag external to the ventilator circuit to deliver hyperinflation (known as "bagging" or "manual hyperinflation"), a new technique has evolved using existing ventilator circuitry (known as "ventilator hyperinflation"). One conservative ventilator hyperinflation protocol has demonstrated equivalence with manual hyperinflation in sputum clearance. DESIGN: A randomized crossover study. METHOD: Patients received manual hyperinflation and ventilator hyperinflation in two randomly ordered treatments on the same day by the same physiotherapist, using a ventilator hyperinflation protocol involving titration of hyperinflation according to airway pressure. RESULTS: Between 2013 and 2018, 48 patients were enrolled in the study. Physiotherapy treatment using ventilator hyperinflation yielded significantly more wet weight sputum (median 2.84 g, IQR 1.81, 4.22) than treatment using manual hyperinflation (median 1.5 g, IQR 0.73, 2.31, P < .001), without significant differences in secondary measures. CONCLUSIONS: A more sophisticated approach to the titration of the volume delivered using ventilator hyperinflation relative to the airway pressure resulted in greater wet weight sputum cleared during physiotherapy treatment. RELEVANCE TO CLINICAL PRACTICE: The results presented in this paper demonstrate that the application of ventilator hyperinflation using peak airway pressure rather than tidal volume may be superior in facilitating sputum clearance and improved oxygenation without patient harm.

Performance of manual hyperinflation: consistency and modification of the technique by intensive care unit nurses during physiotherapy.

AIMS AND OBJECTIVES: To assess the consistency and safety of manual hyperinflation delivery by nurses of variable clinical experience using a resuscitator bag during physiotherapy treatment. BACKGROUND: Manual hyperinflation involves the delivery of larger than normal gas volumes to intubated patients and is routinely used by nurses in collaboration with physiotherapists for the management of retained sputum. The aim is to deliver slow deep breaths with an inspiratory hold without unsafe airway pressures, lung volumes or haemodynamic changes. In addition, nursing staff should be able to 'feel' differences in resistance and adjust their technique accordingly. DESIGN: Prospective observational study utilising the simulation of a mechanically ventilated patient. METHODS: Thirty-three nurses delivered manual hyperinflation to a SimMan3G mannequin who had three distinct lung scenarios applied (normal; asthma; Acute Respiratory Distress Syndrome) in randomised order during simulated physiotherapy treatment. Respiratory rate, tidal volume (Vt ), mean inspiratory flow rate (Vt /Ti), and peak airway pressure data were generated. RESULTS: Over all scenarios, mean respiratory rate = 12·3 breaths/minute, mean Vt  = 638·6 mls, mean inflation time = 1·3 seconds and peak airway pressure exceeded 40 cm H2 O in 41% of breaths, although only in 10% of breaths during the 'normal' lung scenario. CONCLUSIONS: Experienced nurses were able to manually hyperinflate 'normal' patients in a simulated setting safely. Despite their knowledge of barotrauma, unsafe airway pressures were delivered in some scenarios. RELEVANCE TO CLINICAL PRACTICE: Training with regard to safe airway pressures, breath hold and adequate volumes is recommended for all nurses undertaking the procedure. Nurses and physiotherapists must closely monitor the patient's condition during manual hyperinflation thereby recognising changes with regard to lung compliance and airway resistance, with nurses responding by altering their technique. The addition of a pressure manometer in the circuit may improve patient safety when performing manual hyperinflation.

Ventilator versus manual hyperinflation in clearing sputum in ventilated intensive care unit patients.

The aim of hyperinflation in the ventilated intensive care unit patient is to increase oxygenation, reverse lung collapse and clear sputum. The efficacy and consistency of manual hyperventilation is well supported in the literature, but there is limited published evidence supporting hyperventilation utilising a ventilator. Despite this, a recent survey established that almost 40% of Australian tertiary intensive care units utilise ventilator hyperinflation. The aim of this non-inferiority cross-over study was to determine whether ventilator hyperinflation was as effective as manual hyperinflation in clearing sputum from patients receiving mechanical ventilation using a prescriptive ventilator hyperinflation protocol. Forty-six patients received two randomly ordered physiotherapy treatments on the same day by the same physiotherapist. The efficacy of the hyperinflation modes was measured by sputum wet weight. Secondary measures included compliance, tidal volume, airway pressure and PaO2/FiO2 ratio. There was no difference in wet weight of sputum cleared using ventilator hyperinflation or manual hyperinflation (mean 3.2 g, P=0.989). Further, no difference in compliance (P=0.823), tidal volume (P=0.219), heart rate (P=0.579), respiratory rate (P=0.929) or mean arterial pressure (P=0.593) was detected. A statistically significant difference was seen in mean airway pressure (P=0.002) between techniques. The effect of techniques on the PaO2/FiO2 response ratio was dependent on time (interaction P=0.024). Physiotherapy using ventilator hyperinflation cleared a comparable amount of sputum and was as safe as manual hyperinflation. This research describes a ventilator hyperinflation protocol that will serve as a platform for continued discussion, research and development of its application in ventilated patients.

A survey of the use of ventilator hyperinflation in Australian tertiary intensive care units.

OBJECTIVE: To ascertain the prevalence of use of ventilator hyperinflation (VHI) by physiotherapists practising in tertiary Australian intensive care units in the management of artificially ventilated patients, and whether standard protocols are in place in these facilities. DESIGN, SETTING AND PARTICIPANTS: A prospective, multicentre prevalence survey of 64 Australian hospitals with tertiary ICU facilities and physiotherapists. The cohort was compiled from details provided by the Australian and New Zealand Intensive Care Society Centre for Outcome and Resource Evaluation. Senior physiotherapists at participating sites completed a telephone questionnaire regarding the implementation of VHI at their facility. RESULTS: The response rate was 100%. Twenty-five facilities reported using VHI. There was broad agreement on the indications and contraindications for the technique and little difference in the dosage of VHI for the purpose of either sputum clearance or respiratory recruitment manoeuvre. The most common position used for treatment (71% of patients) was side lying with the affected side uppermost. CONCLUSIONS: Our survey provides information on the nature and the extent of VHI utilisation by physiotherapists in Australian tertiary ICUs. These data can now be pooled to develop standardised evidence-based VHI protocols for both spontaneous and controlled ventilation modes.