Improving survival in COPD using NPPV (Kohnlein 2014)

A prospective, randomised, controlled trial of NPPV in severe stable COPD¹

Thomas Köhnlein, Wolfram Windisch, Dieter Köhler, Anna Drabik, Jens Geiseler, Sylvia Hartl, Ortrud Karg, Gerhard Laier-Groeneveld, Stefano Nava, Bernd Schönhofer, Bernd Schucher, Karl Wegscheider, Carl P Criée, Tobias Welte

Introduction

Previous studies of the effect of noninvasive positive pressure ventilation (NPPV) in chronic obstructive pulmonary disease (COPD) have not demonstrated strong evidence of an improvement in survival.

This study investigated the effect of using long-term NPPV to reduce hypercapnia and increase survival.

Methods

195 patients with advanced, stable hypercapnic COPD were randomly assigned to either continue standard treatment or to receive additional NPPV for at least 12 months.

Primary endpoint

The primary endpoint was 1-year all-cause mortality.

Secondary endpoints

Secondary endpoints were arterial oxygen pressure (PaO₂), arterial oxygen saturation (SaO₂), pH, bicarbonate (HCO₃), forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), residual volume/total lung capacity, six-minute walk distance and three health-related quality of life summary measures.

Limitations

It would be recommended to set iBR to the patient’s spontaneous respiratory rate (i.e. 16 bpm) and re-evaluate Ti Max.
SpO₂ was not normalised despite pressure reaching Max PS. Therefore consider increasing Max PS and EPAP.

Conclusions

COPD patient who had nocturnal desaturations was treated on both S/T mode and iVAPS mode.
iVAPS mode improved patient comfort and ventilation.
However, care needs to be taken when adjusting settings from S/T mode to iVAPS mode.
By optimising settings, normalised gas exchange is expected to be achieved in this patient.

Results

Primary endpoint: all-cause mortality

67% of patients in the control group and 88% of patients in the intervention group were still alive 1 year after randomisation.

Secondary endpoints:

Continuous 1-year NPPV treatment was associated with significant improvements in PaO₂, pH, bicarbonate FEV₁ and health-related quality of life.

The authors commented:

"To our knowledge, this trial brings for the first time strong supporting evidence that NPPV targeted to greatly reduce PaCO₂ (decrease baseline PaCO₂ by ≥20% or achieve PaCO₂ <6.5kPa [48.1 mm Hg]) improves long-term survival."

Kohnlein T, et al. Non-invasive positive pressure ventilation for the treatment of severe stable chronic obstructive pulmonary disease: a prospective, multicentre, randomised, controlled clinical trial. Lancet Respir Med 2014 Sep;2(9):698-705.