Impact of Preoperative Liver Function on Short-Term HeartMate 3 Outcomes.

Although left ventricular assist device (LVAD) therapy is associated with improved survival, the impact of preoperative liver function on short-term outcomes is unclear. We conducted a retrospective review of all primary HeartMate 3 LVAD implants at a single center. Composite metrics of hepatic function including the model for end-stage liver disease (MELD), the MELD with sodium, and the MELD excluding international normalized ratio (MELD-XI) were evaluated. Receiver operator characteristic curves were compared to determine which equation was most predictive of 1-year survival. Primary stratification was based on MELD-XI tertiles. Secondary stratification was based on hypoalbuminemia (<3.0 mg/100 ml). A total of 94 patients underwent primary LVAD implantation from 2017 to 2022. MELD-XI and hypoalbuminemia were most associated with 1-year outcomes. When stratified by MELD tertiles, higher MELD was strongly associated with decreased 30 days (100.00% vs 100.00% vs 90.32%, p = 0.04), 1-year (93.00% vs 93.32% vs 69.79%, p = 0.01), and 2-year survival (93.00% vs 83.21% vs 69.79%, p = 0.04). In addition, while hypoalbuminemia was associated with similar 30 days (97.87% vs 95.74%, p = 0.56) survival, it was associated with a significant decrease in 1-year (92.93% vs 77.92%, p = 0.03) and 2-year survival (92.93% vs 68.89%, p <0.01). These results persisted on multivariable analysis for both MELD-XI score (p = 0.04) and hypoalbuminemia (p = 0.04). In conclusion, this is the first study to demonstrate that preoperative MELD-XI score and serum albumin levels are associated with short-term HeartMate 3 outcomes.

Impact of sea level change on coastal soil organic matter, priming effects and prokaryotic community assembly.

Salt marshes are coastal areas storing high amounts of soil organic matter (SOM) while simultaneously being prone to tidal changes. Here, SOM-decomposition and accompanied priming effects (PE), which describe interactions between labile and old SOM, were studied under controlled flooding conditions. Soil samples from two Wadden Sea salt marsh zones, pioneer (Pio), flooded two times/day, and lower salt marsh (Low), flooded ∼eight times/month, were measured for 56 days concerning CO2-efflux and prokaryotic community shifts during three different inundation-treatments: total-drained (Drained), all-time-flooded (Waterlogged) or temporal-flooding (Tidal). Priming was induced by 14C-glucose addition. CO2-efflux from soil followed Low>Pio and Tidal>Drained>Waterlogged, likely due to O2-depletion and moisture maintenance, two key factors governed by tidal inundation with regard to SOM mineralisation. PEs in both zones were positive (Drained) or absent (Waterlogged, Tidal), presumably as a result of prokaryotes switching from production of extracellular enzymes to direct incorporation of labile C. A doubled amount of prokaryotic biomass in Low compared to Pio probably induced higher chances of cometabolic effects and higher PE. 16S-rRNA-gene-amplicon-based analysis revealed differences in bacterial and archaeal community composition between both zones, revealing temporal niche adaptation with flooding treatment. Strongest alterations were found in Drained, likely due to inundation-mediated changes in C-binding capacities.

Effects of Inundation, Nutrient Availability and Plant Species Diversity on Fine Root Mass and Morphology Across a Saltmarsh Flooding Gradient.

Saltmarsh plants are exposed to multiple stresses including tidal inundation, salinity, wave action and sediment anoxia, which require specific root system adaptations to secure sufficient resource capture and firm anchorage in a temporary toxic environment. It is well known that many saltmarsh species develop large below-ground biomass (roots and rhizomes) but relations between fine roots, in particular, and the abiotic conditions in salt marshes are widely unknown. We studied fine root mass (<2 mm in diameter), fine root depth distribution and fine root morphology in three typical communities (Spartina anglica-dominated pioneer zone, Atriplex portulacoides-dominated lower marsh, Elytrigia atherica-dominated upper marsh) across elevational gradients in two tidal salt marshes of the German North Sea coast [a mostly sandy marsh on a barrier island (Spiekeroog), and a silty-clayey marsh on the mainland coast (Westerhever)]. Fine root mass in the 0-40 cm profile ranged between 750 and 2,500 g m-2 in all plots with maxima at both sites in the lower marsh with intermediate inundation frequency and highest plant species richness indicating an effect of biodiversity on fine root mass. Fine root mass and, even more, total fine root surface area (maximum 340 m2 m-2) were high compared to terrestrial grasslands, and were greater in the nutrient-poorer Spiekeroog marsh. Fine root density showed only a slight or no decrease toward 40 cm depth. We conclude that the standing fine root mass and morphology of these salt marshes is mainly under control of species identity and nutrient availability, but species richness is especially influential. The plants of the pioneer zone and lower marsh possess well adapted fine roots and large standing root masses despite the often water-saturated sediment.

Steatorrhea and Hyperoxaluria in Severely Obese Patients Before and After Roux-en-Y Gastric Bypass.

BACKGROUND AND AIMS: Hyperoxaluria after Roux-en-Y gastric bypass (RYGB) is generally attributed to fat malabsorption. If hyperoxaluria is indeed caused by fat malabsorption, magnitudes of hyperoxaluria and steatorrhea should correlate. Severely obese patients, prior to bypass, ingest excess dietary fat that can produce hyperphagic steatorrhea. The primary objective of the study was to determine whether urine oxalate excretion correlates with elements of fat balance in severely obese patients before and after RYGB. METHODS: Fat balance and urine oxalate excretion were measured simultaneously in 26 severely obese patients before and 1 year after RYGB, while patients consumed their usual diet. At these time points, stool and urine samples were collected. Steatorrhea and hyperoxaluria were defined as fecal fat >7 g/day and urine oxalate >40 mg/day. Differences were evaluated using paired 2-tailed t tests. RESULTS: Prior to RYGB, 12 of 26 patients had mild to moderate steatorrhea. Average urine oxalate excretion was 61 mg/day; there was no correlation between fecal fat and urine oxalate excretion. After RYGB, 24 of 26 patients had steatorrhea and urine oxalate excretion averaged 69 mg/day, with a positive correlation between fecal fat and urine oxalate excretions (r = 0.71, P < .001). For each 10 g/day increase in fecal fat output, fecal water excretion increased only 46 mL/day. CONCLUSIONS: Steatorrhea and hyperoxaluria were common in obese patients before bypass, but hyperoxaluria was not caused by excess unabsorbed fatty acids. Hyperphagia, obesity, or metabolic syndrome could have produced this previously unrecognized hyperoxaluric state by stimulating absorption or endogenous synthesis of oxalate. Hyperoxaluria after RYGB correlated with steatorrhea and was presumably caused by excess fatty acids in the intestinal lumen. Because post-bypass steatorrhea caused little increase in fecal water excretion, most patients with steatorrhea did not consider themselves to have diarrhea. Before and after RYGB, high oxalate intake contributed to the severity of hyperoxaluria.

Intestinal perforation caused by insertion of a nasogastric tube late after gastric bypass.

A 57-year-old woman, who had undergone Roux-en-Y gastric bypass surgery 9 years earlier, was admitted to the intensive care unit because of pneumonia. Despite antibiotic therapy, she died 40 days later, apparently because of sepsis and organ failure related to the pneumonia. However, the patient's family requested an autopsy, which revealed that her death was due to perforation of the Roux limb of her gastric bypass, which had resulted in severe peritonitis. The perforation was caused by a nasogastric tube inserted for enteral nutrition. We discuss ways nasogastric tubes might be inserted more safely after gastric bypass, the response of Baylor University Medical Center at Dallas to this complication, and the role of autopsy in improving the quality of hospital care.

Disseminated aspergillosis following infliximab therapy in an immunosuppressed patient with Crohn's disease and chronic hepatitis C: a case study and review of the literature.

A 55-year-old white woman with a greater than 25-year history of Crohn's disease developed disseminated aspergillosis following combination therapy with Methylprednisolone, azathioprine, and infliximab. The patient was hospitalized 11 days after initiation of infliximab for respiratory symptoms and developed respiratory failure, coma, and died. Postmortem examination revealed disseminated Aspergillus fumigatus involving multiple organs. This case demonstrates that combined treatment with infliximab, methylprednisone, and azathioprine may induce severe immunosuppression and depressed cellular immunity, leading to severe opportunistic infections. Given the increasing use of antitumor necrosis factor agents, physicians should be aware of the risk of opportunistic infections and be vigilant about diagnosing and aggressively treating these infections to reduce the risk of disseminated disease.

Stimulated active potassium secretion in a patient with colonic pseudo-obstruction: a new mechanism of secretory diarrhea.

BACKGROUND & AIMS: Secretory diarrhea is caused by inhibition of intestinal active sodium absorption and stimulation of active chloride secretion. The resulting increase in fecal sodium salts causes an isotonic increase in fecal water output. Abnormalities in potassium transport are not known to be a cause of secretory diarrhea. The aim of our report is to describe a patient with secretory diarrhea that was mediated by excess intestinal secretion of potassium. METHODS: A 78-year-old woman developed colonic pseudo-obstruction, complicated by severe diarrhea and hypokalemia. Her stools were collected quantitatively on 11 occasions and analyzed for electrolyte concentrations. Rectosigmoid potential difference was measured. RESULTS: The diarrheal fluid had a very high potassium concentration (130-170 mEq/L) and a very low sodium concentration (4-15 mEq/L). Stool potassium losses were as high as 256 mEq/day (normal, 9 mEq/day), and fecal sodium losses were never higher than 13 mEq/day. Potential difference between colonic lumen and a peripheral reference electrode was -14 mV (lumen side negative). CONCLUSIONS: Fecal potassium salts were the exclusive driving force for severe secretory diarrhea in a patient with colonic pseudo-obstruction. The high fecal output of potassium was due to stimulation of active colonic potassium secretion, possibly because of changes in autonomic nervous system activity and distention of the colon in association with colonic pseudo-obstruction. The extremely low fecal excretion of sodium indicates that active sodium absorption was not inhibited. This case study reveals an ion transport mechanism of secretory diarrhea that has not been previously appreciated.