Korean J Anesthesiol.  2002 Oct;43(4):462-467. 10.4097/kjae.2002.43.4.462.

Effect of Combined Hyperventilation and Mannitol on Cerebral Blood Flow and Cerebral O2 Metabolism during a Craniectomy

• Kim JH
• Kim KS
• Moon BK
• Cho KG
• Shin YS
• Lee YJ
• Kim JS

• KMID: 2033620
• DOI: http://doi.org/10.4097/kjae.2002.43.4.462

Abstract

BACKGROUND: There are therapies to lower intracranial pressure (ICP) including head elevation, hyperventilation, diuretics injection, intravenous mannitol, hypothermia, cerebrospinal fluid drainage, and cerebral resection in neurosurgical patients. However in recent reports, hyperventilation followed by mannitol administration may lead to cerebral ischemia. Therefore, we investigated the effect of 0.5-1.0 g/kg mannitol administration on jugular venous oxygen saturation (SjVO2) and cerebral arterial- jugular venous oxygen content difference (AVDO2) at PaCO2 25-30 mmHg and 35-40 mmHg in patients undergoing neurosurgery.
METHODS
We studied 17 patients undergoing neurosurgery in the Ajou University Hospital. Anesthesia was induced with fentanyl, midazolam, thiopental, and vecuronium, and maintained with O2-Air-Isoflorane, a continuous infusion of fentanyl, and vecuronium. Patients were divided into two groups. Group 1 (n = 10) which is PaCO2 25-30 mmHg and Group 2 (n = 7) which is PaCO2 35-40 mmHg by controlling ventilator. Measurements of SjVO2 and AVDO2 in following time intervals: I = preinjection of mannitol, II = postinjection 20 minutes of mannitol, III = postinjection 40 minutes of mannitol were obtained for each group. 0.5-1.0 g/kg mannitol was administered intravenously just at duramater opening.
RESULTS
Hemodynamics and hematologics were not significantly different among the two groups. SjVO2 of each group are as follows; Group 1; I (70.3+/-8.1%), II (66.3+/-6.9%), III (69.1+/-7.9%) and Group 2; I (78.6+/-7.4%), II (75.1+/-8.1%), III (76.0+/-11.2%). Hyperventilation significantly decreased SjVO2. AVDO2 was not significantly different but SjVO2 in II was significantly decreased compared with I and III in Group 1 (20% patients).
CONCLUSIONS
Mannitol produced a change of SjVO2 and AVDO2 during hyperventilation. Therefore, intravenous mannitol during hyperventilation should be given cautiously according to the patients status because it may cause cerebral ischemia in critical patients.

Keyword

Cerebral arterial-jugular venous oxygen content difference; hyperventilation; jugular venous oxygen saturation; mannitol

MeSH Terms

Anesthesia
Brain Ischemia
Cerebrospinal Fluid
Diuretics
Drainage
Fentanyl
Head
Hemodynamics
Humans
Hyperventilation*
Hypothermia
Injections, Intravenous
Intracranial Pressure
Mannitol*
Metabolism*
Midazolam
Neurosurgery
Oxygen
Thiopental
Vecuronium Bromide
Ventilators, Mechanical
Diuretics
Fentanyl
Mannitol
Midazolam
Oxygen
Thiopental
Vecuronium Bromide