Surgical strategy to prevent cardiac injury during reoperation in infants

<p>Abstract</p> <p>Introduction</p> <p>Simplified Aortic Cannulation (SAC), wherein the innominate artery is used as the arterial inflow site rather than the ascending aorta, has proved to be a useful technique for arterial cannulation especially for small neonates undergoing complex cardiac operations. Since few technical options are available for re-entry cardiac injuries in small infants, we postulate that this technique may be equally helpful in those situations.</p> <p>Case Presentation</p> <p>We employed SAC in 4 infants undergoing reoperative cardiac surgery (prior Norwood, n = 2; prior arterial switch operation with suprasystemic pulmonary artery pressures after a Le Compte maneuver, n = 1; prior Ebstein's anomaly, n = 1). In all cases the innominate artery was exposed at the level of the supra-sternal notch, and a 3.5 mm expanded polytetrafluoroethylene (ePTFE) graft was anastomosed to the innominate artery (n = 3), and a 10 French cannula inserted into the graft for whole-body perfusion. Right atrial cannulation was obtained by dividing the anterior aspect of the diaphragm at the level of the xiphisternum, gaining easy access to the right atrial-inferior vena cava junction, without separating the sternal edges.</p> <p>Discussion and Evaluation</p> <p>All four infants successfully underwent their operations using SAC. In one case (2^ndstage palliation for hypoplastic left heart syndrome) a cardiac injury occurred upon sternal reentry, but utilizing SAC, this was repaired without consequence.</p> <p>Conclusion</p> <p>Simplified aortic cannulation and direct right atrial cannulation may be obtained without dividing the sternum in complex reoperative infant surgeries, without making additional incisions. This may be life-saving in reoperative cardiac injuries in small infants.</p

Simplified aortic cannulation (SAC) – a useful technique for neonates with small aortas

A simplified means of arterial cannulation for cardiopulmonary bypass in small neonates and those infants with diminutive aortas, or requiring reconstruction of the ascending aorta, is presented. It involves suturing a long 3.5 mm graft to the innominate artery and inserting the arterial cannula into the end of the graft. This technique improves exposure, thereby greatly simplifying many complex repairs, and may be used for initiation of ECMO or for hybrid procedures in the postoperative period

Cryopreserved homograft valves in the pulmonary position: Risk analysis for intermediate-term failure

AbstractObjective: The purpose of this study was to examine the durability of cryopreserved homografts used to replace the “pulmonary” valve and to identify factors associated with their late deterioration. Methods: We reviewed our entire experience (1985-1997) with 331 survivors in whom cryopreserved homograft valves (pulmonary, n = 304; aortic, n = 27) were used to reconstruct the pulmonary outflow tract. Median age was 14 years (range, 2 days–62 years). Operations included Ross operation (n = 259), tetralogy of Fallot (n = 41), truncus arteriosus (n = 14), Rastelli operation (n = 11), and others (n = 6). Median follow-up was 3.8 years (range, 0.2–11.2 years); late echographic follow-up was complete for 97% of patients. Homograft failure was defined as the need for explantation and valve-related death; homograft dysfunction was defined as a pulmonary insufficiency grade 3/4 or greater and a transvalvular gradient of 40 mm Hg or greater. Results: Homograft failure occurred in 9% (30 of 331 patients; Kaplan-Meier); freedom from failure was 82% ± 4% at 8 years. Homograft dysfunction occurred in 12% (39 of 331 patients), although freedom from dysfunction was 76% ± 4% at 8 years. For aortic homografts, this was 56% ± 11%, compared to 80% ± 4% for pulmonary homografts (P = .003). For patients aged less than 3 years (n = 38), this was 51% ± 12%, compared with 87% ± 4% for older patients (P = .0001). By multivariable analysis, younger age of homograft donors, non-Ross operation, and later year of operation were associated with homograft failure; younger age of homograft donors, later year of operation, and use of an aortic homograft were associated with homograft dysfunction. Conclusions: Homograft valves function satisfactorily in the pulmonary position at mid-term follow-up. The pulmonary homograft valve appears to be more durable than the aortic homograft valve in the pulmonary position. (J Thorac Cardiovasc Surg 1999;117:141-7

"Nested" cryptic diversity in a widespread marine ecosystem engineer: a challenge for detecting biological invasions

<p>Abstract</p> <p>Background</p> <p>Ecosystem engineers facilitate habitat formation and enhance biodiversity, but when they become invasive, they present a critical threat to native communities because they can drastically alter the receiving habitat. Management of such species thus needs to be a priority, but the poorly resolved taxonomy of many ecosystem engineers represents a major obstacle to correctly identifying them as being either native or introduced. We address this dilemma by studying the sea squirt <it>Pyura stolonifera</it>, an important ecosystem engineer that dominates coastal communities particularly in the southern hemisphere. Using DNA sequence data from four independently evolving loci, we aimed to determine levels of cryptic diversity, the invasive or native status of each regional population, and the most appropriate sampling design for identifying the geographic ranges of each evolutionary unit.</p> <p>Results</p> <p>Extensive sampling in Africa, Australasia and South America revealed the existence of "nested" levels of cryptic diversity, in which at least five distinct species can be further subdivided into smaller-scale genetic lineages. The ranges of several evolutionary units are limited by well-documented biogeographic disjunctions. Evidence for both cryptic native diversity and the existence of invasive populations allows us to considerably refine our view of the native versus introduced status of the evolutionary units within <it>Pyura stolonifera </it>in the different coastal communities they dominate.</p> <p>Conclusions</p> <p>This study illustrates the degree of taxonomic complexity that can exist within widespread species for which there is little taxonomic expertise, and it highlights the challenges involved in distinguishing between indigenous and introduced populations. The fact that multiple genetic lineages can be native to a single geographic region indicates that it is imperative to obtain samples from as many different habitat types and biotic zones as possible when attempting to identify the source region of a putative invader. "Nested" cryptic diversity, and the difficulties in correctly identifying invasive species that arise from it, represent a major challenge for managing biodiversity.</p

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

Genomic Dissection of Bipolar Disorder and Schizophrenia, Including 28 Subphenotypes

publisher: Elsevier articletitle: Genomic Dissection of Bipolar Disorder and Schizophrenia, Including 28 Subphenotypes journaltitle: Cell articlelink: https://doi.org/10.1016/j.cell.2018.05.046 content_type: article copyright: © 2018 Elsevier Inc

Bloodless Surgery in a Pediatric Jehovah’s Witness

Pediatric cardiac surgery in Jehovah’s Witness patients who refuse the use of blood products remains a challenge because of the extreme hemodilution caused by priming the circuit and subsequent cardiopulmonary bypass. We report our successful strategy for reducing the prime volume for a 2-year-old Jehovah’s Witness patient who required open heart surgery. We modified our conventional bypass circuit requirements for this size child by incorporating a lower prime oxygenator and reducing the size of the venous line and circuit, which decreased the circuit prime volume. We managed to reduce our initial sanguineous prime volume from 315 to 210 mL. The prime was further reduced to 160 mL by minimizing circuit length at the field and with venous prime sequestration prebypass. The postbypass hematocrit was 31%. Bloodless pediatric cardiac surgery in Jehovah’s Witness patients can be performed safely. Incorporating a lower prime oxygenator into a revised circuit alleviated the need for blood transfusion and allowed us to achieve our calculated flow rate of 2.6 L/min/m2 while maintaining a hematocrit of 31%

Mycotic Pseudoaneurysm Complicating Stent Placement for Native Aortic Coarctation in a Child

Mycotic aneurysms of the aorta are uncommon life-threatening lesions. Sporadic cases have been reported in adults after surgical intervention for native and recurrent coarctation of the aorta. We report a case of a rapidly progressive, large mycotic pseudoaneurysm in a 13-year-old boy 3 months after a bare-metal stent was used to treat native coarctation. The boy presented with slurred speech, bacteremia, and systemic septic embolization. During an emergency operation, the pseudoaneurysm was resected, and the infected aorta was replaced with an interposition graft. This rare complication may occur early or late after stent placement for coarctation of the aorta