Association between Enterocyte Injury and Mortality in Patients on Hemodialysis Who Underwent Cardiac Surgery: An Exploratory Study

Predicting outcomes of mesenteric ischemia postcardiac surgery: A systematic review

OBJECTIVE

This systematic review aims to identify predictors of outcomes of mesenteric ischemia in patients following cardiac surgery.

METHODS

A comprehensive literature search was done on EMBASE, PubMed, Ovid MEDLINE, and SCOPUS using keywords relating to bowel ischemia and cardiac surgery. Database search results were screened by at least two authors and 32 articles were selected for inclusion in this review.

RESULTS

Data on 1907 patients were analyzed. The mean age was 70.0 ± 2.99 years and the prevalence of bowel ischemia was 1.74%. Advanced age was a significant risk factor. 63.16% of patients reported were men, and 58.4% of patients died in hospital. There was heterogeneity in the reported significance of the following preoperative risk factors: hypertension, smoking status, type 2 diabetes mellitus, end-stage renal disease, preoperative left ventricular ejection fraction <35%. Cardiopulmonary bypass (CPB) time, preoperative/operative intra-aortic balloon pump (IABP) support, and inotrope usage were significantly associated with the development of mesenteric ischemia; however, other intraoperative factors including the type of cardiac surgery and duration of aortic cross-clamping had varying levels of reported significance. There were discrepancies in the reported significance of leukocytosis and metabolic acidosis (pH <7.3) as postoperative markers. Postoperative vasopressor use, prolonged ventilation time, and elevation in lactate, transaminases, creatinine, and intestinal fatty acid-binding protein (IFABP) levels were found to be strongly associated with bowel ischemia.

CONCLUSION

This systematic review found the strongest associations of mesenteric ischemia postcardiac surgery to be advanced age, CPB time, rise in lactate, transaminases, creatinine, and IFABP. IABP support, vasopressor, and inotrope use as well as prolonged ventilation were strongly linked too.

Association between enterocyte injury and fluid balance in patients with septic shock: a post hoc exploratory analysis of a prospective observational study

Background

The required fluid volume differs among patients with septic shock. Enterocyte injury caused by shock may increase the need for fluid by triggering a systematic inflammatory response or an ischemia-reperfusion injury in the presence of intestinal ischemia/necrosis. This study aimed to evaluate the association between enterocyte injury and positive fluid balance in patients with septic shock.

Methods

This study was a post hoc exploratory analysis of a prospective observational study that assessed the association between serum intestinal fatty acid-binding protein, a biomarker of enterocyte injury, and mortality in patients with septic shock. Intestinal fatty acid-binding protein levels were recorded on intensive care unit admission, and fluid balance was monitored from intensive care unit admission to Day 7. The association between intestinal fatty acid-binding protein levels at admission and the infusion balance during the early period after intensive care unit admission was evaluated. Multiple linear regression analysis, with adjustments for severity score and renal function, was performed.

Results

Overall, data of 57 patients were analyzed. Logarithmically transformed intestinal fatty acid-binding protein levels were significantly associated with cumulative fluid balance per body weight at 24 and 72 h post-intensive care unit admission both before (Pearson’s r = 0.490 [95% confidence interval: 0.263–0.666]; P < 0.001 and r = 0.479 [95% confidence interval: 0.240–0.664]; P < 0.001, respectively) and after (estimate, 14.4 [95% confidence interval: 4.1–24.7]; P = 0.007 and estimate, 26.9 [95% confidence interval: 11.0–42.7]; P = 0.001, respectively) adjusting for severity score and renal function.

Conclusions

Enterocyte injury was significantly associated with cumulative fluid balance at 24 and 72 h post-intensive care unit admission. Enterocyte injury in patients with septic shock may be related to excessive fluid accumulation during the early period after intensive care unit admission.

Enteral nutrition and dynamics of citrulline and intestinal fatty acid-binding protein in adult ICU patients

BACKGROUND AND AIMS

Plasma citrulline and intestinal fatty acid binding protein (I-FABP) are biomarkers reflecting enterocyte function and intestinal mucosal injury. The aim was to describe daily dynamics of citrulline and I-FABP concentrations in association with enteral nutrition (EN) in adult ICU patients. We hypothesized that success or failure of EN is reflected by differences in citrulline and I-FABP levels at admission, as well as in daily dynamics over the first week.

METHODS

The present study was a planned sub-study of the iSOFA study (ClinicalTrials.gov Identifier: NCT02613000). With delayed informed consent we included adult (18 years or older) patients admitted for unlimited care to 5 ICUs in Europe. Citrulline and I-FABP were assessed and nutritional data recorded daily during the first week of the patients' ICU stay.

RESULTS

The study included 224 patients with 693 plasma samples analyzed for citrulline and 695 for I-FABP. The median ICU stay was 2 (IQR 1-4) days and 35 patients (15.6 %) stayed in the ICU for ≥ 7 days. The majority of patients (184/224; 82.1 %) received EN or oral nutrition (ON) during their ICU stay, in 164 patients (73.2 %) nutrition was started within 48 h of admission (early enteral or oral nutrition, EEN/ON). Median biomarker concentrations on admission were: citrulline 24.5 (IQR 18.1-31.7) μmol/L and I-FABP 2763 (1326-4805) pg/mL. Reference range for citrulline was 17-46 μmol/L and for I-FABP 377-2049 pg/mL. Patients with EEN/ON demonstrated an increase in citrulline concentrations over the first week in ICU unlike those not receiving EEN/ON (P = 0.049 for the mean log-citrulline values over time between groups) as well as higher average citrulline concentrations. Success of EEN/ON (80 % of caloric target achieved by day 4) was associated with citrulline values increasing from day 4, whereas a slight decrease was observed with unsuccessful EEN/ON. However, these dynamics over time were not statistically significantly different (P = 0.654). Patients with EEN/ON unexpectedly had I-FABP values higher than those without (average values for all days P = 0.004). Median I-FABP values on day 3 were higher with successful EEN/ON (646 (IQR 313-1116) vs 278 (IQR 190-701) pg/mL, P = 0.022).

CONCLUSIONS

EEN/ON was associated with higher values and different dynamics of citrulline over the first week in ICU. No clear difference of measured biomarkers was seen when patients were compared according to success of EEN/ON. Our study does not allow suggesting certain thresholds of citrulline nor I-FABP that could be used for bedside decision-making with regard to EN. This study was a planned sub-study of the iSOFA study (ClinicalTrials.gov Identifier: NCT02613000).

Intestinal fatty acid-binding protein and acute gastrointestinal injury grade in postoperative cardiac surgery patients

BACKGROUND AND AIM

Gastrointestinal complications post cardiac surgery are infrequent but difficult to diagnose and carry a high mortality. Plasma intestinal fatty acid-binding protein (I-FABP) concentrations and the relationship between I-FABP, gastrointestinal dysfunction, and postoperative outcomes were investigated in patients who developed gastrointestinal dysfunction (acute gastrointestinal injury [AGI] grade ≥2) and those with normal gastrointestinal function.

METHODS

Patients with (AGI 2 group, n = 11) and without (matched controls, AGI 0 group, n = 22) early postoperative gastrointestinal dysfunction were extracted from a larger single-center prospective observational study, including adults undergoing elective cardiac surgery with extracorporeal circulation, and investigated in this nested case-control analysis.

RESULTS

Both groups displayed variations in I-FABP concentrations with higher I-FABP on postoperative Day 1 compared to baseline and postoperative Days 2 and 3 (p < .001 and p = .005, respectively). The AGI 2 group had higher I-FABP concentrations on Day 2 compared to the AGI 0 group (p = .024). I-FABP on Day 2 correlated positively with AGI grade over the first 3 days (p = .036, p = .021 and p = .018, respectively). High I-FABP (defined as fourth quartile concentrations) on Day 1 was associated with more prolonged surgical procedures (p < .05). Furthermore, fourth quartile I-FABP on Day 1 and early gastrointestinal dysfunction were associated with higher frequencies of postoperative organ dysfunction (p < .05) and gastrointestinal complications (p < .05), and higher 365-day mortality.

CONCLUSION

The present study indicates an association between intraoperative gastrointestinal injury, postoperative gastrointestinal dysfunction and gastrointestinal complications. A high-powered study is needed to further explore this relationship and the interpretation of I-FABP concentrations in individual cardiac surgery patients.