ICU · Respiratory / ventilation

Acute Severe COPD Exacerbation: NIV and Invasive Ventilation — Comprehensive ICU Management

Also known as AECOPD · Acute exacerbation of COPD · COPD type 2 respiratory failure · Bilevel NIV in COPD · Plant trial NIV · Permissive hypercapnia · Auto-PEEP ventilation · Anthonisen criteria · Controlled oxygen COPD

An acute severe exacerbation of COPD (AECOPD) causing hypercapnic (type 2) respiratory failure is an ICU emergency built on three pillars: titrated controlled oxygen (SpO2 88-92 per cent — the range recommended by respiratory and ambulance guidelines; titrated oxygen reduced mortality, hypercapnia and acidosis versus high-flow oxygen in the prehospital RCT, and SpO2 under 88% or over 96% each about doubles the risk of a serious adverse outcome), a medical bundle (air-driven nebulised salbutamol with ipratropium, prednisolone 40 mg daily for 5 days — the REDUCE trial — and antibiotics when Anthonisen criteria are met), and escalating respiratory support driven by the arterial pH. Bilevel non-invasive ventilation, inspiratory pressure titrated toward a tidal volume of about 6-10 mL/kg predicted body weight (HAPPEN), is first-line for the acidotic patient (pH <7.35) — the Plant trial (Lancet 2000) and the Lightowler Cochrane meta-analysis (BMJ 2003) prove it cuts intubation, mortality, and length of stay. Intubate when NIV fails (worsening acidosis despite an adequate trial, falling GCS, peri-arrest) and ventilate with a low rate, low tidal volume and long expiratory time, keeping external PEEP below intrinsic PEEP — hyperinflation rose when rate, minute ventilation or tidal volume rose (Tuxen), and auto-PEEP can severely depress cardiac output (Pepe and Marini).