Cerebral vasoreactivity to acetazolamide is not impaired in patients with severe sepsis.
BACKGROUND
The pathophysiology of sepsis-associated encephalopathy (SAE) is not entirely clear, but one of the possible underlying mechanisms is the alteration of the cerebral microvascular function. The aim of the present work was to test whether cerebral vasomotor reactivity is impaired in patients with severe sepsis.


METHODS
Patients fulfilling the criteria of clinical sepsis and showing at least 2 organ dysfunctions were included (n = 16). Nonseptic healthy persons without previous diseases affecting cerebral vasoreactivity served as controls (n = 16). Transcranial Doppler blood flow velocities were measured at rest and at 5, 10, 15, and 20 minutes after intravenous administration of 15 mg/kg acetazolamide. The time course of the acetazolamide effect on cerebral blood flow velocity (cerebrovascular reactivity [CVR]) and the maximal vasodilatory effect of acetazolemide (cerebrovascular reserve capacity [CRC]) were compared among the groups.


RESULTS
Absolute blood flow velocities after administration of the vasodilator drug did not differ between control and septic patients. Assessment of the time course of the vasomotor reaction showed that patients with sepsis reacted in a similar fashion to the vasodilatory stimulus than control persons. When assessing the maximal vasodilatory ability of the cerebral arterioles to acetazolamide during vasomotor testing, we found that there was no difference in vasodilatory ability between septic and healthy subjects (CRC controls, 54.8% ± 11.1%; CRC sepsis-associated encephalopathy, 61.1% ± 34.4%; P = .49).


CONCLUSIONS
We conclude that cerebrovascular reactivity is not impaired in patients with severe sepsis. It is conceivable that cerebral vasoreactivity may be differently involved at different severity stages of the septic process.
Department of Anaesthesiology and Intensive Care, Neurology, University of Debrecen, Health and Medical Science Centre, Debrecen, Hungary. fulesdi@dote.hu
Béla
B
Fülesdi
Szilárd
S
Szatmári
Csaba
C
Antek
Zoltán
Z
Fülep
Péter
P
Sárkány
László
L
Csiba
Csilla
C
Molnár
D000086:Acetazolamide / Q000494:pharmacology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D001927:Brain Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018805:Sepsis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017585:Ultrasonography, Doppler, Transcranial; D014665:Vasodilator Agents / Q000494:pharmacology*
D014665:Vasodilator Agents; D000086:Acetazolamide