The value of BURP (=backwards-upwards-rightwards-pressure of the laryn
x) was tested as a improvement of the visualisation of the larynx. Sim
ultaneously we wanted to assess the value of different predictive test
s of a difficult intubation, which are easy to perform as bedside test
s. Patients and material: 1993 patients of all different surgical clin
ics in a tertiary care hospital in Switzerland were tested, the comple
te anaesthesiological staff was involved. We registered the original M
allampati classes, the thyromental distances of Patil and Frerk and th
e difference of the jugulomental distances in maximally reclined and n
eutral head position according to Chow. Every anaesthetist also noted
his personal,subjective opinion of a possible difficult intubation. Un
der optimal conditions for intubation we assessed the grade of laryngo
scopy according to Wilson and applied BURP if the grade was 3 or highe
r. Both laryngoscopic grades and the difficulty of intubation were not
ed. Results: In our study we found 12.5% awkward (Wilson G3-G5) and 4.
7% difficult (Wilson G4-G5) laryngoscopies. These could be changed wit
h BURP into 5.0% and 1.9% respectively. With BURP we found 1.8% of dif
ficult intubations. During our study we did not find any patients, who
m we could not intubate either with a mandrin inside the tube or with
help of the fiberoptic. The relation between sensitivity and specifici
ty was in ail single predictors and in two combinations very low. Our
personal subjective predictions proofed to be better, but the rate of
false negatives was too high for clinical use. Conclusion: BURP is a v
aluable method for rendering the majority of difficult laryngoscopies
into easy ones. It is very easy to learn and does not need any additio
nal equipment. Three commonly used and recommended predictive tests of
the difficult intubation proofed to be of little use in clinical prac
tice.