I. Schindler et al., MODERATE INDUCED HYPOTENSION PROVIDES SATISFACTORY OPERATING-CONDITIONS IN MAXILLOFACIAL SURGERY, Acta anaesthesiologica Scandinavica, 38(4), 1994, pp. 384-387
Patients scheduled for maxillofacial surgery were randomly assigned to
receive isoflurane (n = 22) or nitroglycerin (n = 18) in order to ind
uce hypotension. Surgeons, blinded for the actual level of blood press
ure and the technique used for inducing hypotension, were asked to rat
e operating conditions on a scale from 1 to 5. Systolic arterial press
ure (SAP) and mean arterial pressure (MAP) were reduced by 26% for bot
h groups. Although blood pressure levels showed little variation throu
ghout the induced hypotension period, scores of 2 to 5 were given sign
ificantly more often at incision and at 30 min compared to the followi
ng measuring points (P < 0.01). In total, the surgical field was rated
significantly more often with a score of 1 and 2 than with a score of
3 to 5 (P < 0.01). A relation between score and SAP and/or MAP could
not be found. There was also no relation between scores and the techni
que used for hypotension. Our data suggest that, with the exception of
the first half hour of surgery, on average a SAP of 89 mmHg and a MAP
of 65 mmHg were sufficient to produce satisfactory operating conditio
ns.