Table 1

Clinical findings on attendance at hospital

Patient characteristics	1	2	3
Smoker	+	+	+
Past respiratory disease	None	None	Asthma
Symptoms
Breathlessness	+	++	++
Chest tightness	+	++	++
Headache	+	+	+
Haemoptysis	_	+	_
Rigors	+	+	+
Nausea	_	_	+
Wheeze	_	_	_
Investigations
Temperature (°C)	38.9	38.4	38.7
Pulse (beats/minute)	140	110	100
% O₂ saturation (on high flow oxygen)	91	94	92
MetHb%	0.6	0.5	0.9
Exhaled CO (parts per million)	1.4	1.6	1.2
White cell count	21.6	18.4	12.7
Liver function tests	Normal	Not done	Increased γGT
FEV₁ (l) (%pred)	3.89 (89)	1.51 (40)	2.25 (51)
FVC (l) (pred)	5.45 (105)	1.77 (39)	2.52 (48)
Chest x ray infiltrates	+	++	++