Early quantitative CT perfusion parameters variation for prediction of delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage.

OBJECTIVES: To prospectively evaluate the predictive value of cerebral perfusion-computerized tomography (CTP) parameters variation between day0 and day4 after aneurysmal subarachnoid haemorrhage (aSAH). METHODS: Mean transit time (MTT) and cerebral blood flow (CBF) values were compared between patients with delayed cerebral ischemia (DCI+ group) and patients without DCI (DCI- group) for previously published optimal cutoff values and for variations of MTT (ΔMTT) and of CBF (ΔCBF) values between day0 and day4. DCI+ was defined as a cerebral infarction on 3-months follow-up MRI. RESULTS: Among 47 included patients, 10 suffered DCI+. Published optimal cutoff values did not predict DCI, either at day0 or at day4. Conversely, ΔMTT and ΔCBF significantly differed between the DCI+ and DCI- groups, with optimal ΔMTT and ΔCBF values of 0.91 seconds (83.9 % sensitivity, 79.5 % specificity, AUC 0.84) and -7.6 mL/100 g/min (100 % sensitivity, 71.4 % specificity, AUC 0.86), respectively. In multivariate analysis, ΔCBF (OR = 1.91, IC95% 1.13-3.23 per each 20 % decrease of ΔCBF) and ΔMTT values (OR = 14.70, IC95% 4.85-44.52 per each 20 % increase of ΔMTT) were independent predictors of DCI. CONCLUSIONS: Assessment of MTT and CBF value variations between day0 and day4 may serve as an early imaging surrogate for prediction of DCI in aSAH. KEY POINTS: • CT perfusion values are an imaging surrogate for prediction of DCI. • Early variations (day0-day4) after aneurysmal subarachnoid haemorrhage predicted DCI. • A CBF decrease of 7.6 mL/min/100 g predicted DCI with 100 % sensitivity. • An MTT increase of 0.91 seconds predicted DCI with 83.9 % sensitivity. • DCI risk multiplied by 2 per 20 % ΔCBF decrease and by 15 per 20 % ΔMTT increase.

Normothermic cardiopulmonary bypass and myocardial cardioplegic protection for neonatal arterial switch operation.

OBJECTIVE: Hypothermic cardiopulmonary bypass (CPB) associated with cold myocardial protection is commonly used to perform neonatal cardiac surgery. Hypothermia is usually chosen to preserve the brain in case of failure of oxygen delivery whatever it may result from. Nowadays, there is a growing number of evidence demonstrating that hypothermia induces deleterious effects, which may culminate in organ dysfunctions. In 2001, we started a protocol where the heart and the body were no longer cooled, in all the procedures, including the arterial switch operation (ASO), except those with aortic arch reconstruction. METHODS: Because data on the neonatal arterial switch operation were prospectively gathered in our unit (and included fine biochemical analysis of myocardial damage), we have compared two consecutive populations of arterial switch operation to sort out the impact of normothermic CPB and normothermic cardioplegia. RESULTS: The results show that warm cardiopulmonary bypass associated with warm cardioplegia is feasible for ASO, and that most of the operative data are similar to hypothermic bypass, none are worse. Among the postoperative data, the cardiac troponin I (cTnI) time course showed significantly lower values in the normothermic group after 24 h (4.46 ng ml(-1) vs 6.17 ng ml(-1) (p = 0.027)), time to extubation is improved (32+/-26 h vs 70+/-69 h (p = 0.02)) and there is a trend to reduce the ICU length of stay (3.5+/-1.5 days vs 5.6+/-3.9 days (p = 0.08)), and consequently the cost of surgery. CONCLUSION: Normothermic cardiopulmonary bypass is feasible for ASO and seems to allow a faster recovery time.