Moyamoya disease in children and its anesthetic implications: A review.

Moyamoya disease is a rare, progressive cerebral vasculopathy which most commonly presents in the first and fourth decades of life. The mainstay of treatment is surgical revascularization; without treatment, most patients experience ischemic or hemorrhagic strokes. This report reviews moyamoya disease, its associated conditions, surgical treatment techniques, and anesthetic management of patients with moyamoya disease.

Rapid Blood Transfusion: The Importance of Hemodilution and Needleless Connectors.

INTRODUCTION:  Large-bore cannulas are critical to administering IV fluids and blood products during resuscitation and treatment of hemorrhage. Although catheter flow rates for crystalloid solutions are well defined, rapid administration of blood products is poorly characterized. In this in vitro study, we examined the effects of hemodilution and needleless connectors on red blood cell (RBC) flow rates. METHODS:  To determine RBC flow rates through large-bore cannulae, a crystalloid solution (Normosol®, Hospira, Lake Forest, IL) or RBC units were warmed and delivered under pressure (360 mmHg) using a Level 1 H-1200 Fast Flow Fluid Warmer (Smiths Medical, St. Paul, MN). Flow rates for crystalloid, packed RBCs and diluted RBCs were determined using a stopwatch. Additionally, the effect of the MaxPlus® clear needleless connector (CareFusion, San Diego, CA) was measured in all three infusion groups. RESULTS:  Flow rates for undiluted RBC units were 53% slower than crystalloid solution (220 mL/min vs. 463 mL/min; p=0.0003), however, when RBC units were diluted to a hematocrit of ~30% flow rate improved to 369 mL/min (p=0.005). The addition of the MaxPlus® needleless connector reduced flow of crystalloid solution by 47% (245 mL/min; p=0.0001), undiluted RBCs by 64% (78 mL/min; p=0.01), and diluted RBCs by 51% (180 mL/min; p=0.00003). Compared to undiluted RBC units, hemodilution increased RBC delivery rate through a MaxPlus® connector by 130% (p=0.004) and by 68% (p=0.02) when the catheter was directly connected to the Level 1 tubing (MaxPlus® excluded). CONCLUSION:  In settings requiring rapid transfusion of RBC units, needleless connectors should not be used and hemodilution should be considered in order to decrease the time required to deliver an equivalent red cell mass.

Management of brain tumors presenting in pregnancy: a case series and systematic review.

Patients who present with brain tumors during pregnancy require unique imaging and neurosurgical, obstetrical, and anesthetic considerations. Here, we review the literature and discuss the management of patients who present with brain tumors during pregnancy. Between 2009 and 2019, 9 patients were diagnosed at our institution with brain tumors during pregnancy. Clinical information was extracted from the electronic medical records. The median age at presentation was 29 years (range, 25-38 years). The most common symptoms at presentation included headache (n=5), visual changes (n=4), hemiparesis (n=3), and seizures (n=3). The median gestational age at presentation was 20.5 weeks (range, 11-37 weeks). Of note, 8 patients (89%) delivered healthy newborns, and 1 patient terminated her pregnancy. In addition, 5 patients (56%) required neurosurgical procedures during pregnancy (gestational ages, 14-37 weeks) because of disease progression (n=2) or neurologic instability (n=3). There was 1 episode of postneurosurgery morbidity (pulmonary embolism [PE]) and no surgical maternal mortality. The median length of follow-up was 15 months (range, 6-45 months). In cases demonstrating unstable or progressive neurosurgical status past the point of fetal viability, neurosurgical intervention should be considered. The physiological and pharmacodynamic changes of pregnancy substantially affect anesthetic management. Pregnancy termination should be discussed and offered to the patient when aggressive disease necessitates immediate treatment and the fetal gestational age remains previable, although neurologically stable patients may be able to continue the pregnancy to term. Ultimately, pregnant patients with brain tumors require an individualized approach to their care under the guidance of a multidisciplinary team.

Acetaminophen Does Not Reduce Postoperative Opiate Consumption in Patients Undergoing Craniotomy for Cerebral Revascularization: A Randomized Control Trial.

Background Postoperative management in patients undergoing craniotomy is unique and challenging. We utilized a population of patients who underwent bilateral extracranial-to-intracranial (EC-IC bypass) revascularization procedures for moyamoya disease and hypothesized that 1 gram (gm) of intravenous (IV) acetaminophen given immediately after intubation and again 45 minutes prior to the end of craniotomy may be more effective than saline in minimizing opiate consumption and decreasing pain scores. Methods In a double-blind, randomized, placebo-controlled crossover pilot study, 40 craniotomies in 20 patients were studied. A random number generator assigned patients to receive either 1 gram of IV acetaminophen or an equal volume of normal saline immediately after intubation and again 45 minutes prior to the end of their first operation. For the second surgery, patients received the study drug (IV acetaminophen or normal saline) that they did not receive during their first surgery. Results In the IV acetaminophen group, the average 24-hour postoperative fentanyl equivalent consumption was decreased but the difference was not statistically significant: 228 micrograms compared to 312 micrograms in the placebo group (Figure 1; p = 0.09). Pain scores did not significantly differ between the IV acetaminophen group and the placebo group in postoperative hours 0-12 (Figure 2; p = 0.44) or 24 (Figure 3; p = 0.77). Conclusion Our study demonstrates that in patients receiving bilateral craniotomies for moyamoya disease, IV acetaminophen when given immediately after intubation and again 45 minutes prior to closure does not significantly decrease 12- or 24-hour postoperative opiate consumption.

Relational congruence facilitates neural mapping of spatial and temporal magnitudes in preverbal infants.

Mental representations of space, time, and number are fundamental to our understanding of the world around us. It should come as no surprise that representations of each are functional early in human development, appear to share a common format, and may be maintained by overlapping cortical structures. The consequences of these similarities for early learning and behavior are poorly understood. We investigated this issue by assessing neurophysiological processing of audio-visual temporal and spatial magnitude pairs using event-related potentials (ERPs) with young infants. We observed differential early processing and later enhanced attentional processing for pairings of spatial and temporal magnitudes that were relationally congruent (short visual character paired with a short auditory tone or long visual character paired with a long auditory tone) compared to the same stimuli paired in a relationally incongruent manner (short visual character with the long auditory tone or long visual character with a short tone). Unlike previous studies, these results were not dependent on a redundancy of information between the senses or an alignment of congruent magnitude properties within a single sense modality. Rather, these results demonstrate that mental representations of space and time interact to bias learning before formal instruction or the acquisition of spatial language.