Chronic obstructive pulmonary disease: noninvasive ventilation reduced need for intubation.

Clinical bottom line (level 1b)

Patients with acute exacerbations of chronic obstructive pulmonary disease who were given noninvasive ventilation were less likely to need endotracheal intubation than those given standard therapy alone (NNT = 2 at unknown) .
Patients given noninvasive ventilation were less likely to die in-hospital than those given standard therapy alone (NNT = 5 at unknown) .

Brochard et al: The New England Journal of Medicine 1995; 333 (13): 817-822

Expires November 2003

The study

Unblinded concealed randomised trial with intention-to-treat
Setting: five hospitals, France

85 patients (aged mean 70 years, ?% male) acute exacerbations of chronic obstructive pulmonary disease

Excluded if

respiratory rate <12 breaths per minute or the need for immediate intubation

tracheotomy or endotracheal intubation performed before admission

administration of sedatives within the previous 12 hours

central nervous system disorder unrelated to hypercapnic encephalopathy or hypoxemia

cardiac arrest within previous 5 days

cardiogenic pulmonary oedema

kyphoscoliosis as the cause of chronic respiratory failure or a neuromuscular disorder

upper airway obstruction or asthma

clear cause of decompensation requiring specific treatment (eg. peritonitis, septic shock, acute MI, pulmonary thromboembolism, pneumothorax, haemoptysis, severe pneumonia or recent surgery or trauma)

facial deformity

enrolment in other investigative protocols

refusal to undergo endotracheal intubation

Control Group: (n = 42, 42 analysed): standard treatment- oxygen limited to a maximal flow rate of 5 litres per minute, with nasal prongs, in order to achieve an arterial oxygen saturation above 90%. Drugs used included subcutaneous heparin, antibiotics and bronchodilators, with the correction of electrolyte abnormalities.
Experimental Group: (n = 43, 43 analysed): standard treatment plus pressure-support ventilation through a face mask. Pressure support was initially adjusted to give an arterial oxygen saturation of 90%. Patients underwent at least 6 hours of noninvasive ventilation per day.

100% followed for ? endotracheal intubation and mortality
Outcome notes:

required endotracheal intubation : This was determined by the use of criteria set out before the trial. These included respiratory arrest, respiratory pauses with loss of consciousness or gasping for air, psychomotor agitation requiring sedation, heart rate <50 beats per minute, haemodynamic instability with systolic blood pressure <70 mmHg. Others included respiratory rate >35, arterial pH <7.30 or paO2 <45 mm Hg despite O2 treatment

The evidence

Outcome	Time to outcome	CER	EER	RRR (95% CI)	ARR (95% CI)	NNT (95% CI)
required endotracheal intubation	days	31 (73.8%)	11 (25.8%)	65.0% (40.0% to 80.0%)	48.23% (29.6% to 66.85%)	2 (1 to 3)
in-hospital mortality	days	12 (28.6%)	4 (9.30%)	67.0% (7.00% to 89.0%)	19.27% (3.08% to 35.46%)	5 (3 to 32)

The authors used the Mantel-Haenszel test to adjust for endotracheal intubation when comparing mortality rates. They found no significant difference which suggests that the number of patients requiring intubation was the main factor explaining the difference in mortality.

Citation

Brochard L, Mancebo J, Wysocki M, et al: Noninvasive ventilation for acute exacerbations of chronic obstructive pulmonary disease. The New England Journal of Medicine 1995; 333 (13): 817-822

Search Terms: chronic obstructive pulmonary disease, COPD and therapy in PubMed and Cochrane
Contributor: Clare Wotton and Musab Hayatli, November 1999
Reviewer: Gerard Ryan

_{Clinical Question.}

_Patient	_{acute exacerbations of COPD}
_{Intervention or Exposure}	_{noninvasive ventilation}
_Comparison	_{standard ventilation}
_Outcome	_{in-hospital mortality and the need for intubation}