Stump pressure as a guide to the safety of permanent occlusion of the internal carotid artery

Abstract

Does the absolute value of the stump pressure (post-occlusion back pressure) become a useful index of a good collateral circulation? The authors continuously monitored the mean arterial pressure before, during and after 20-minute balloon test occlusion in 24 patients. The stump pressure was then compared with the results of 99mTc-hexa-methyl propyleneamine (99mTc-HMPAO) single photon emission computed tomography (SPECT) performed after 20 minutes of test occlusion. Patients who failed to tolerate even brief periods of carotid occlusion and showed asymmetric decreases in cerebral blood flow (CBF) on SPECT were divided into high and moderate risk groups. Those with no significant change in CBF on the occluded side formed the minimum risk group. Mean stump pressure was over 50 mmHg in three of a total of 13 patients in the high and moderate risk groups, and below 50 mmHg in two of the 11 patients in the minimum risk group. The ratios of the initial mean stump pressure to the pre-occlusion mean arterial pressure (%) and of the final mean stump pressure at the end of occlusion to the post-opening mean arterial pressure (%) did not exceed 58% in any patient in the high and moderate risk groups, and were at least 60% in all patients of the minimum risk group. Maintenance of a mean stump pressure of 60% or more of the mean systemic pressure during test occlusion may be a more useful index of a good collateral circulation than the absolute value of mean stump pressure.

Predictors of Carotid Occlusion Intolerance During Proximal Protected Carotid Artery Stenting

“…Proximal occlusion devices stop or reverse flow by occluding the carotid artery, much in the same way that a carotid endarterectomy accomplishes neuro-protection. An OP #40 mm Hg after occlusion of the CCA has been suggested to be a predictor of OI(12,13) during proximal protected CAS, and our study provides the definitive proof of this hypothesis.Measuring blood pressure (stump pressure) in the distal ICA during occlusion of the ICA is reported to be a reliable safety index to predict ischemia after permanent occlusion of the ICA (carotid sacrifice) performed for the management of complex cerebral aneurysms(14). Of note, the OP threshold of 40 mm Hg that we found associated with the development of OI corresponds to the literature regarding balloon test occlusion for carotid sacrifice used by cerebral angiographers(14).…”

“…An OP #40 mm Hg after occlusion of the CCA has been suggested to be a predictor of OI(12,13) during proximal protected CAS, and our study provides the definitive proof of this hypothesis.Measuring blood pressure (stump pressure) in the distal ICA during occlusion of the ICA is reported to be a reliable safety index to predict ischemia after permanent occlusion of the ICA (carotid sacrifice) performed for the management of complex cerebral aneurysms(14). Of note, the OP threshold of 40 mm Hg that we found associated with the development of OI corresponds to the literature regarding balloon test occlusion for carotid sacrifice used by cerebral angiographers(14). Even if other studies demonstrated in a different clinical setting that such low pressure is associated with the development of neurological symptoms, this is the first study to confirm this finding in the setting of proximal protected CAS.…”

Multimodal Assessment for Balloon Test Occlusion of the Internal Carotid Artery

“…Also, the stump pressure at the occluded stump of the ICA is measured. [6][7][8] For the measurement of the cerebral blood flow, various devices including SPECT, 6,16) perfusion CT, [17][18][19] transcranial Dop pler, 20) and PETCT 21) are used. This conversely means that a universal device to measure the cerebral blood flow for the evaluation of ischemic tolerance has not been established.…”

“…[6][7][8] Whether or not the ICA was sufficiently occluded was confirmed according to the change in the stump pressure between before and after ICA occlusion.…”

Preoperative Tumor Embolization

“…Balloon test occlusion is generally performed in a preoperative setting when it is anticipated that one of the vessels supplying the brain will be sacrifi ced. Adjunctive maneuvers including hypotensive challenge [ 28 ], neuropsychological testing [ 29 ], somatosensory-evoked potentials [ 30 ], cerebral oximetry [ 31 ], and electroencephalography [ 32 ] may be considered to reduce the incidence of a false-negative result. In addition, the hemodynamic effects of occlusion can be assessed by measuring the stump pressure [ 69 ], angiographic control runs [ 33 ], transcranial Doppler [ 34 ], xenon 133 imaging [ 35 ], xenon CT [ 36 ], CT perfusion [ 37 ], PET [ 38 ], SPECT [ 39 ], and MR perfusion [ 40 ].…”