Pulsatile Flow Improves Cerebral Blood Flow in Pediatric Cardiopulmonary Bypass

Abstract

The objective of this study was to evaluate the effect of pulsatile flow on cerebral blood flow (CBF) in infants with the use of a mild hypothermic cardiopulmonary bypass (CPB). Thirty infants scheduled for open heart surgery were randomized to the pulsatile group (Group P, n = 15) and nonpulsatile group (Group NP, n = 15). In Group P, pulsatile perfusion was applied during the aortic cross-clamping period, whereas nonpulsatile perfusion was used in Group NP. The systolic peak velocity (Vs), the end of diastolic velocity (Vd), the mean velocity (Vm), and the pulsatility index (PI) and the resistance index (RI) of the middle cerebral artery were measured by a transcranial Doppler (TCD) ultrasound after anesthesia (T1; baseline), at the beginning of CPB (T2), 10 min after aortic cross-clamping (T3), 3 min after declamping (T4), at the cessation of CPB (T5), and at the end of the operation (T6). During T3 and T4, the Vs in Group P was significantly higher than in Group NP. However, there were no statistically significant differences between Vd and Vm. The PI and RI in Group P were also higher than those in Group NP (both P < 0.05). During T5, Vd and Vm were higher in Group P (P < 0.05), whereas there was no difference in Vs. Additionally, PI and RI in Group P were significantly lower than those in Group NP (P < 0.05). However, there was no difference during T6. Pulsatile perfusion may increase CBF and decrease cerebral vascular resistance in the early period after mild hypothermic CPB.

Development of a physiologic ex vivo vessel perfusion system.

“…Studies conducted on the liver show that pulsatile flow sustains total hepatic blood flow more effectively than continuous flow, due to the specific preservation of hepatic arterial and portal venous blood flow (attributed to prevention of hepatic arterial vasoconstriction) 24 . Similar impact was reported in the neurological system, in that lower vascular resistance and higher flow rates were associated with pulsatile versus nonpulsatile flow 23,25 . Studies conducted on the gastrointestinal (GI) system are concerning, where data has shown that continuous flow is significantly more likely to cause GI bleeding than pulsatile flow, with a near ten-fold incidence difference in some cases 26 .…”

Selective head cooling for the treatment of neurologic complications of acute liver failure in a newborn with disseminated herpes infection

“…We used TCDs as a measure of increased ICP in this patient, as invasive monitoring of ICP is often impractical in coagulopathic patients with ALF, and the benefit of such monitoring is not proven. Recently, TCDs have been studied in pediatric traumatic brain injury (TBI) (Melo et al 2011 ), neonatal sepsis (Basu et al 2012 ), cardiopulmonary bypass (Wang et al 2010 ) and extracorporeal membrane oxygenation (O’Brien & Hall 2013 ) as a surrogate for cerebral blood flow. Our patient initially exhibited absent diastolic MCA flow, which improved with another day of head cooling, and correlated with an improved clinical exam.…”

Impact of a Unique International Conference on Pediatric Mechanical Circulatory Support and Pediatric Cardiopulmonary Perfusion Research

“…Not only the quantity, but also the quality of these articles generated by this event based on high‐impact factors (average impact factor is greater than 2.7 annually) are also very impressive. Only during the last 2 years' events, topics covered show the clear evidence of the uniqueness and importance of this conference (Table ) .…”