BACKGROUND: Adequate cerebral perfusion is crucial for a positive neurological outcome in trauma; however, it is difficult to characterize in the acute setting with non-invasive methods. Intra-arterial computed tomography perfusion (IA-CTP) may offer a solution. The aim of this study is to develop an IA-CTP protocol for resuscitation research. METHODS: The study examined intra-arterial contrast administration for CTP acquisition. It consisted of 3 phases: IA contrast dose finding, evaluation of reproducibility, and evaluation during hypotension. Blood pressure and laser doppler flow data were collected. In phase 1, animals underwent CTPs using several IA contrast injection protocols. In phase 2, animals underwent two CTPs seven hours apart using the 2.5mL/s for 3 second protocol. In phase 3, animals underwent CTPs at several pressures following a computer-controlled bleed including euvolemia and at systolic pressures of 60, 40, and 20mmHg. Phase 1 CTPs were evaluated for contrast-to-noise ratio. In phase 2, CTPs were compared within each animal and with laser doppler flow using linear regression. Phase 3 CTPs were graphed against systolic pressure and fitted with a non-linear fit. RESULTS: The protocol utilizing 2.5mL/s for 3 seconds was optimal demonstrating a contrast-tonoise ratio of 40.1 as well as a superior arterial input function curve compared to the 1mL/s bolus. Cerebral blood flow demonstrated high concordance between baseline and end of study CTPs (R2=0.82, p<0.001). Cerebral blood flow also compared moderately well against laser doppler flow during euvolemia (R2=0.53, p=0.03); however laser doppler flow did not perform well during hypovolemia and the favorable concordance was not maintained (R2=0.45, p=0.06). Cerebral blood flow was graphed against systolic blood pressure and fitted with a non-linear fit (R2=0.95, p=0.003). CONCLUSIONS: CTP using intra-arterial contrast injection may offer a novel alternative to traditional CTP protocols that could prove a useful additional tool in the setting of resuscitation research. LEVELS OF EVIDENCE: This is a basic science paper and, therefore, does not require a level of evidence. STUDY TYPE: Basic Science.
BACKGROUND: Adequate cerebral perfusion is crucial for a positive neurological outcome in trauma; however, it is difficult to characterize in the acute setting with non-invasive methods. Intra-arterial computed tomography perfusion (IA-CTP) may offer a solution. The aim of this study is to develop an IA-CTP protocol for resuscitation research. METHODS: The study examined intra-arterial contrast administration for CTP acquisition. It consisted of 3 phases: IA contrast dose finding, evaluation of reproducibility, and evaluation during hypotension. Blood pressure and laser doppler flow data were collected. In phase 1, animals underwent CTPs using several IA contrast injection protocols. In phase 2, animals underwent two CTPs seven hours apart using the 2.5mL/s for 3 second protocol. In phase 3, animals underwent CTPs at several pressures following a computer-controlled bleed including euvolemia and at systolic pressures of 60, 40, and 20mmHg. Phase 1 CTPs were evaluated for contrast-to-noise ratio. In phase 2, CTPs were compared within each animal and with laser doppler flow using linear regression. Phase 3 CTPs were graphed against systolic pressure and fitted with a non-linear fit. RESULTS: The protocol utilizing 2.5mL/s for 3 seconds was optimal demonstrating a contrast-tonoise ratio of 40.1 as well as a superior arterial input function curve compared to the 1mL/s bolus. Cerebral blood flow demonstrated high concordance between baseline and end of study CTPs (R2=0.82, p<0.001). Cerebral blood flow also compared moderately well against laser doppler flow during euvolemia (R2=0.53, p=0.03); however laser doppler flow did not perform well during hypovolemia and the favorable concordance was not maintained (R2=0.45, p=0.06). Cerebral blood flow was graphed against systolic blood pressure and fitted with a non-linear fit (R2=0.95, p=0.003). CONCLUSIONS:CTP using intra-arterial contrast injection may offer a novel alternative to traditional CTP protocols that could prove a useful additional tool in the setting of resuscitation research. LEVELS OF EVIDENCE: This is a basic science paper and, therefore, does not require a level of evidence. STUDY TYPE: Basic Science.
Authors: Joseph Edwards; Hossam Abdou; Neerav Patel; Eric Lang; Michael J Richmond; Todd E Rasmussen; Thomas M Scalea; Jonathan J Morrison Journal: Eur J Trauma Emerg Surg Date: 2022-01-04 Impact factor: 3.693
Authors: David P Stonko; Neerav Patel; Joseph Edwards; Hossam Abdou; Eric Lang; Noha N Elansary; Rebecca Treffalls; Joseph White; Jonathan J Morrison Journal: JVS Vasc Sci Date: 2022-08-17
Authors: David P Stonko; Joseph Edwards; Hossam Abdou; Noha N Elansary; Eric Lang; Samuel G Savidge; Caitlin W Hicks; Jonathan J Morrison Journal: Front Physiol Date: 2022-05-09 Impact factor: 4.755
Authors: David P Stonko; Joseph Edwards; Hossam Abdou; Noha N Elansary; Eric Lang; Samuel G Savidge; Jonathan J Morrison Journal: JVS Vasc Sci Date: 2022-01-04
Authors: Neerav Patel; Joseph Edwards; Hossam Abdou; David P Stonko; Rebecca N Treffalls; Noha N Elansary; Thomas Ptak; Jonathan J Morrison Journal: Front Physiol Date: 2022-10-04 Impact factor: 4.755