COPD: exacerbation: non-invasive ventilation reduced intubation and death in patients with mild-moderate acidosis

Clinical bottom line (level 1b)

  1. Patients with an acute exacerbation of COPD and mild-moderate acidosis who received non-invasive ventilation compared with no ventilation were less likely to require intubation (NN T = 8 at 2 weeks) or die (NN T = 10 at 2 weeks) .
Plant et al: Lancet 2000; 355 : 1931-1935
Expires October 2003

The study

Double-blinded unconcealed randomised trial with intention-to-treat
Setting: medical wards, 14 acute hospitals, UK

236 patients (aged mean 69, 51% female) admitted with an acute exacerbation of COPD and
  • tachypnoea: rate 23 per minute or more
  • pH 7.25 to 7.35 with pCO2 6 kPa or higher
on arrival at respiratory ward (i.e following emergency department treatment)

Excluded if
  • pH < 7.25
  • Glasgow coma scale < 8
  • pneumothorax
  • active treatment deamed inappropriate

    Control Group: (n = 118, 118 analysed): standard therapy
    Experimental Group: (n = 118, 118 analysed): non-invasive ventilation: pressure support via face or nasal mask
    All patients received nebulised salbutamol (5 mg every 4 hours) or terbutaline; nebulised ipratropium (500 microgram every 6 hours); prednisolone 30 mg every day for at least 5 days, and an antibiotic. Aminophylline and doxapram could be given at the discretion of the medical staff.
    100% followed for 14 days
    Outcome notes:
    • need for intubation : any of: - pH < 7.20; pH 7.20 to 7. 25 on 2 occasions 1 hour apart; hypercapnic coma (GCS < 8 and pCO2 > 8 kPa); pO2 < 6 kPa despite maximum tolerated FiO2; cardiorespiratory arrest

    The evidence

    Outcome Time to outcome CER EER RRR
    (95% CI)    		 ARR
    (95% CI)    		 NN T
    (95% CI)
    need for intubation 14 days 32
    (27.1%)    		 18
    (15.3%)    		 44%
    (6% to 66%)    		 11.9%
    (1.55% to 22.2%)    		 8
    (5 to 65)
    death 14 days 24
    (20.3%)    		 12
    (10.2%)    		 50%
    (5% to 74%)    		 10.2%
    (1.09% to 19.3%)    		 10
    (5 to 92)

    Comments

    1. Patients assigned to non-invasive ventilation used it for a mean of 3 days
    2. Each ward team required around 8 hours of training to teach staff how to use the equipment.
    3. Once in use ventilation led to a 26 min increase in nursing workload in the first 8 hours of patient care - there was no difference after this time between the two groups.
    4. Patients in the two groups spent similar lengths of time in hospital - median of 10 days.

    Citation

    1. Plant PK, Owen JL, Elliott MW: early use of non-invasive ventilation for acute exacerbations of chronic obstructive pulmonary disease on general respiratory wards: a multicentre randomised controlled trial. Lancet 2000; 355 : 1931-1935
    Search Terms: from ACP Journal Club other articles noted
    Contributor: Chris Ball, October 2001
    Reviewer:

    Clinical Question.
    Patient COPD exacerbation with mild to moderate acidosis
    Intervention or Exposure non-invasive ventilation
    Comparison no ventilation
    Outcome need for intubation, death
    		•