Plaque Characteristics on CT Angiography Do Not Improve the Ability to Predict Hemodynamic Instability During and After Carotid Angioplasty and Stenting.

BACKGROUND: Hemodynamic instability is commonly seen during carotid angioplasty and stenting. Although prophylactic treatment with anticholinergics is beneficial, selected use in high-risk patients is desirable. This study examines whether plaque characteristics on computed tomography angiography in addition to demographic factors improve predictive capability. METHODS: We retrospectively collected information from 298 carotid angioplasty procedures between January 2013 and December 2018. Nine individuals were excluded due to a previous ipsilateral endarterectomy. Our primary outcome was a decrease of 20% or more in heart rate or blood pressure at angioplasty. Data were analyzed using χ2 tests and regression statistics. RESULTS: Of the 289 patients included for analysis, 57 had intraoperative instability and 26 had postoperative instability. Radiologist interpretation was found to have a risk ratio of 1.63 (95% confidence interval: 1.00-2.65) for intraoperative instability (P=0.080). Intraoperative instability was significantly associated with subsequent postoperative instability (P=0.005). Our regression model included previous endarterectomy and diabetes as predictive factors with a sensitivity of 11.3% and a specificity of 100.0%. Anticholinergic usage was associated with hypotension without coexisting bradycardia with a risk ratio of 2.36 (95% confidence interval: 1.06-5.26; P=0.047). CONCLUSIONS: Individuals without a previous contralateral endarterectomy and/or history of diabetes are at lower risk of hemodynamic instability. The addition of computed tomography angiographic variables does not improve this prediction. Future prospective, randomized work is required to improve our ability to identify and treat individuals at high risk of instability during carotid angioplasty and stenting.

Anesthetic management and outcome in patients during endovascular therapy for acute stroke.

BACKGROUND: Studies of endovascular treatment for acute ischemic stroke have identified general anesthesia as a predictor for poor outcome in comparison with local anesthesia/sedation. This retrospective study attempts to identify modifiable factors associated with poor outcome, while adjusting for baseline stroke severity, in patients receiving general anesthesia. METHODS: We reviewed charts of 129 patients treated between January 2003 and September 2009. The primary outcome was the modified Rankin Score of 0-2 for 3 months poststroke. Predictors of neurologic outcome included baseline National Institutes of Health Stroke Scale score, blood glucose concentration, and age. Additional risk factors evaluated were prolonged stroke onset-treatment interval and systolic blood pressure less than 140 mmHg. Choice of local anesthesia or general anesthesia was recorded. RESULTS: The study group was 96 out of 129 patients for whom modified Rankin Scale scores were available; 48 patients received general anesthesia and 48 local anesthesia. The proportion of patients with "good" outcomes were 15% and 60% in the general anesthesia group and local anesthesia group, respectively (P < 0.001). Lowest systolic blood pressure and general anesthesia were correlated (r = -0.7, P < 0.001). Independent predictors for good neurologic outcome were local anesthesia, systolic blood pressure greater than 140 mmHg, and low baseline stroke scores. CONCLUSIONS: Adjusted for stroke severity, patients who received general anesthesia for treatment are less likely to have a good outcome than those managed with local anesthesia. This may be due to preintervention risk not included in the stroke severity measures. Hypotension, more frequent in the general anesthesia patients, may also contribute.

Levetiracetam reduces anesthetic-induced hyperalgesia in rats.

BACKGROUND: As part of an increase in excitability, small doses of pentobarbital, propofol, and midazolam induce an increased sensitivity to pain. Specific therapy to prevent or reduce this excitability may offer advantages over current clinical management with analgesics and sedatives. The pharmacological profile of the novel antiepileptic drug, levetiracetam, suggests that it may reduce the intensity of the excitatory stages of anesthesia. METHODS: We examined the influence of levetiracetam on the reduction of the nociceptive reflex threshold in rats by sedative doses of pentobarbital, propofol, and midazolam. Measurements of nociceptive reflex threshold to pressure and heat were made and then repeated after intraperitoneal injection of saline or one of three doses of levetiracetam (100, 200, 500 mg/kg). Pentobarbital (30 mg/kg), propofol (30 mg/kg), or midazolam (1.9 mg/kg) were then administered. The reflex threshold was measured every 10 min, starting at 5 min after the sedative injection, until 65 min had elapsed. RESULTS: Levetiracetam did not alter nociceptive reflex threshold in nonsedated animals (P = 0.11) or influence the degree or duration of sedation. The three anesthetic/sedative drugs reduced the nociceptive reflex threshold by 20%-30% of control values. Levetiracetam reduced the hyperreflexia associated with pentobarbital and midazolam (P < 0.05), but not propofol. CONCLUSIONS: These findings support further investigation into the role of levetiracetam in the prevention of anesthetic-induced excitability.