Anesthesia for Carotid Endarterectomy, Angioplasty, and Stent

Effect of clinically uneventful carotid endarterectomy on pentraxin 3 concentration: relationships between cognitive functions, local inflammation, and duration of brain ischemia

INTRODUCTION

The pentraxins are a superfamily of proteins characterized by the presence of a pentraxin domain at the C-terminal. One of them is pentraxin 3 (PTX3), which is of great interest to scientists, primarily due to its function as an endogenous modulator of the inflammatory response. Local inflammation is a common phenomenon during various types of surgery and procedures, and its causes, among others, are local ischemia or tissue irritation. One such procedure is carotid plaque removal by carotid endarterectomy (CEA), which is performed to reduce the risk of stroke.

MATERIAL AND METHODS

The purpose of this study was to investigate the effect of CEA on PTX3 concentration and the relationship between cognitive functions and the duration of brain ischemia in patients. We evaluated the relationships using blood collected from patients undergoing CEA, the Mini-Mental State Examination (MMSE) questionnaire, and commercially available ELISA tests.

RESULTS

Results: We found that the concentration of PTX3 increased after surgery (from 0.59 ± 0.11 to 1.29 ± 0.29 ng mL-1; P < 0.01). Also, a decrease in the MMSE score was observed 24 hours after the procedure (P < 0.01). However, just one month after the procedure, it significantly increased compared to the day of admission to the hospital (P < 0.01). Our results did not demonstrate any interactions between the tested parameters. It can be concluded that neither the changes in PTX3 concentration following the procedure nor the timing of these changes directly contribute to the temporary deterioration of cognitive functions observed after CEA.

CONCLUSIONS

PTX3 increases independently of the duration of cerebral hypoxemia/ hypercapnia after clamping the carotid artery. This rise is an inflammatory marker that occurs independently within the central nervous system.

Raising Systemic Blood Pressure to Delay Irreversible Intestinal Ischemia in a Swine Model of Proximal Superior Mesenteric ArteryOcclusion

INTRODUCTION

Acute proximal superior mesenteric artery (SMA) occlusion is highly lethal, and adjuncts are needed to mitigate ischemic injury until definitive therapy. We hypothesized that raising mean arterial pressure (MAP) >90 mmHg with norepinephrine may delay irreversible bowel ischemia by increasing gastroduodenal artery (GDA) flow despite possible pressor-induced vasospasm.

METHODS

12 anesthetized swine underwent laparotomy, GDA flow probe placement, and proximal SMA exposure and clamping. Animals were randomized between conventional therapy (CT) versus targeted MAP >90 mmHg (MAP push; MP) where norepinephrine was titrated after 45 min of SMA occlusion. Animals were followed until bowel death or 4 h. Kaplan-Meier bowel survival, mean normalized GDA flow, and histology were compared.

RESULTS

12 swine (mean 57.8 ± 7.6 kgs) were included, six per group. Baseline weight, HR, MAP and GDA flows were not different. Within 5 min following SMA clamping, all 12 animals had an increase in MAP without other intervention from 81.7 to 105.5 mmHg (29.1%, P < 0.01) with a concomitant 74.9% increase in GDA flow as compared to baseline (P < 0.01). Beyond 45 min postclamp, MAP was greater in the MP group as intended, as were GDA flows. Median time to irreversibly ischemic bowel was 31% longer for MAP push animals (CT: 178 versus MP: 233 min, P = 0.006), Hazard Ratio of CT 8.85 (95% CI: 1.86-42.06); 3/6 MP animals versus 0/6 CT animals with bowel survived to predetermined end point.

CONCLUSIONS

In this swine model of acute complete proximal SMA occlusion, increasing MAP >90 mmHg with norepinephrine was associated with an increase in macrovascular blood flow through the GDA and bowel survival. Norepinephrine was not associated with worse bowel survival and a MAP push may increase the time window where ischemic bowel can be salvaged.