Clinical application of induced mild hypercapnia as a preoperative test predicting results of STA-MCA bypass surgery in patients with ischemic cerebrovascular disease--in relation to induced hypertension method
Ohtsuka, K.; Nakagawa, Y.; Tsuru, M.; Takei, H.; Itoh, K.
No Shinkei Geka. Neurological Surgery 10(2): 167-174
1982
ISSN/ISBN: 0301-2603 PMID: 6801534 Document Number: 193133
The clinical usefulness of induced mild hypercapnia as a new preoperative test was evaluated. Regional cerebral blood flow (rCBF) was measured with 133Xe intracarotid injection and somatosensory evoked potentials (SEP) were recorded under normocapnia and normotension, mild hypercapnia ranging from 43-55 mm Hg PaCO2 [arterial CO2 partial pressure] with normotension, and mild hypertension of an increase of mean systemic arterial pressure by 30-40 mm Hg with normocapnia in 8 stroke patients with neurologic deficits. Five cases were operated on and followed up for 6-9 mo. In patients with completed stroke and minor neurological deficits, whose rCBF in the parietal region was reduced by 25.4% in mean value compared to control, SEP (V1) was definitely restored by induced mild hypercapnia. In patients with completed stroke and moderate neurological deficits whose parietal rCBF decreased by 32.1% in mean value compared to control level, SEP (V1) was restored more obviously by induced hypertension than by induced hypercapnia. Four surgically treated cases, whose SEP (V1) responded well by induced mild hypercapnia, showed excellent recovery suggesting an effectiveness of induced mild hypercapnia as a preoperative prediction of functional recovery following bypass surgery.