Nelson, James A.

BACKGROUND AND OBJECTIVES: Venous air embolism (VAE) can cause significant morbidity and mortality. Prevention and management of VAE include cessation of air entrainment, positioning changes, and hemodynamic support. The degree to which position change and cardiac output (CO) moderate resolution of intracardiac air has not been rigorously studied using contemporary transesophageal echocardiography (TEE). METHODS: This observational cohort-type study aimed to identify the effect of supine vs sitting positioning on the movement and resolution of intracardiac air. In 20 patients undergoing seated neurosurgery, central venous air aspiration catheters were placed through the median basilic vein. TEE was used to estimate the time required for clearance of agitated microbubbles from the right atrium and ventricle in both the supine and sitting position. Estimates of CO were also obtained echocardiographically in each position. RESULTS: Average clearance time was faster in the sitting vs the supine position with no significant difference in CO. A negative correlation between CO and right atrial clearance time across all patients was demonstrated with a Pearson coefficient of −0.4 (95% CI −0.07, −0.65) with P = .02. CONCLUSION: During VAE, both patient position and CO can significantly affect how bubbles move through intracardiac chambers. However, augmenting CO during VAE may be clinically more feasible, efficient, and productive than changing positioning—especially during crises unless the changing in position is intended to halt the entrainment of air. Further TEE studies of intravascular air movement affected by other position changes (lateral, reverse Trendelenburg) and vasopressors should be considered.

Background and objectives Few cadaveric studies have evaluated the dye spread with superficial parasternal intercostal plane (SPIP) blocks. In this study, we examined the dye spread of an ultrasound-guided SPIP block in a human cadaveric model with single and double injection techniques. Methods Seven single and four double ultrasound-guided SPIP blocks were performed in seven unembalmed human cadavers using an in-plane approach with the transducer oriented parasagitally 1 cm lateral to the sternum. For the single SPIP, 20 mL of 0.166% methylene blue was injected in the second or third intercostal space into the plane between the Pec major muscle and internal intercostal muscles. For the double SPIP, 10 mL of 0.166% methylene blue was injected in the SPIP at one intercostal space with an additional 10 mL injected in the SPIP two intercostal spaces caudally. The extent of dye spread was documented. Results For all SPIP injections, there was consistent mediolateral spread from the sternum to the mid-clavicular line, with many extending laterally to the anterior axillary line. There was craniocaudal spread to a median of 2 intercostal muscles with a single SPIP and 3 intercostal muscles with a double SPIP. There was a median spread to 1 intercostal nerve for the single SPIP and 1.5 intercostal nerves with the double SPIP. Conclusions The SPIP block demonstrated limited spread in this cadaver study. A single injection of this block may be of limited value and multiple SPIP injections may be needed to have adequate spread for anterior thoracic procedures.

Abstract Background Fabry’s disease, an X-linked lysosomal storage disorder, shares cardiac manifestations with hypertrophic cardiomyopathy (HCM). We underscore the importance of considering Fabry’s disease as a differential diagnosis in HCM patients, highlighting genetic testing’s role in cardiomyopathy evaluation. Case summary Three male patients with left ventricular hypertrophy were initially diagnosed with HCM but were later found to have Fabry’s disease through genetic testing. Atypical features such as renal dysfunction and conduction abnormalities raised suspicion. Genetic testing confirmed diagnosis, guiding tailored management. Discussion Fabry’s disease poses diagnostic challenges due to its resemblance to HCM. Genetic testing enables precise diagnosis and personalized management, especially in cases with atypical presentations. Early recognition and intervention, facilitated by genetic testing, can improve patient outcomes in Fabry’s disease.

Background: Fabry's disease (FD), an X-linked lysosomal storage disorder, can present with cardiac manifestations similar to HCM. We aim to emphasize considering FD as a differential diagnosis in patients with HCM while highlighting the role of genetic testing in evaluating left ventricular hypertrophy (LVH). Cases Presentation: We present a case series of 3 patients with LVH. Despite initial clinical suspicion of primary HCM, genetic testing confirmed the diagnosis of FD. Patient 1: A 38-year-old male with no prior medical history presented with presyncope, lightheadedness, and chest tightness. EKG, Echo, and cardiac MRI suggested apical HCM. Genetic testing indicated FD. Patient 2: A 62-year-old male sought a second opinion regarding his diffuse HCM. EKG suggested RBBB. Echo showed a binary appearance of the myocardium, concentric LVH. Genetic testing confirmed FD. Patient 3: A 64-year-old male with a history of hypertension and renal disease underwent evaluation for kidney transplantation. Echo showed severely increased concentric LVH and Valsalva-induced intracavitary gradient/obstruction. Alpha-galactosidase level returned very low, suggesting FD, which was confirmed by genetic testing. Discussion: FD can be challenging to diagnose due to overlapping clinical and imaging features with HCM, leading to misdiagnosis and delayed management. Therefore, Genetic testing should be offered to all patients with suspected HCM to exclude phenocopies. Particularly, those with progressive HCM and atypical clinical features (renal disease and family history predominantly in males) and imaging features (conduction abnormalities on EKG, binary appearance on Echo). Early identification of FD enables appropriate management, including enzyme replacement therapy, potentially improving clinical outcomes. Conclusions: FD should be considered as a differential diagnosis in patients with HCM. Genetic testing plays a vital role in evaluating patients with HCM.

AbstractCoagulopathy is common during left ventricular assist device (LVAD) implantation, treatment of which can be challenging given the often‐limited ability for the right ventricle to accommodate volume transfusion after device initiation with 20% to 40% of patients developing right ventricular failure (RVF). Transfusion of plasma late on cardiopulmonary bypass (CPB) combined with ultrafiltration may replace clotting factors while reducing volume administration. We compared outcomes in patients undergoing LVAD implantation receiving plasma on CPB and ultrafiltration with traditional transfusion practices. Co‐primary outcomes needed for blood product transfusion in the first 6 and 24 hours after CPB. Secondary outcomes included metrics of morbidity and mortality. 396 patients were analyzed (59 plasma on CPB). Patients receiving plasma on CPB had a greater volume of blood products transfused (3764 vs. 2741 mL first 6 hours; 6059 vs. 4305 mL first 24 hours) in unadjusted analysis. In adjusted analysis, plasma transfusion on CPB with ultrafiltration had no significant effect on the primary outcomes of blood products given in the first 6 hours (estimated effect size 982 [−428, 2392] mL, P = .17) and 24 hours (estimated effect size 1076 [−904, 3057] mL, P = .29). Patients receiving plasma on CPB were more likely on either vasopressors or inotropes at 24 hours after ICU admission (P = .01), however, indices of coagulopathy and RVF were similar between groups. While prospective studies would be necessary to definitively evaluate the clinical utility of this strategy, no signal for benefit was observed suggesting plasma should not be used for this purpose.

Hydroxocobalamin (vitamin B12a) is an emerging treatment for vasoplegic syndrome (VS) associated with cardiopulmonary bypass (CPB). Given its cost and scarcity, an institutional guideline for its use as a rescue treatment in cases of suspected VS was developed. Hemodynamic variables and vasopressor requirements were reviewed for a series of 24 post-CPB patients who received B12a. Favorable changes in hemodynamic parameters and vasopressor requirements were seen after B12a administration although guideline criteria for VS were inconsistently met. These findings support the continued study of B12a in patients with CPB-associated VS.