Acute kidney injury after open ventral hernia repair: an analysis of the 2005-2012 ACS-NSQIP datasets

Optimizing Perioperative Fluid Management in Complex Abdominal Wall Reconstruction to Prevent Postoperative Acute Kidney Injury

BACKGROUND

Acute kidney injury (AKI) is a serious postoperative complication of abdominal wall reconstruction that can significantly impact outcomes of these patients. This study examines AKI following abdominal wall hernia repair to determine incidence and risk factors and outline potential mitigation strategies.

METHODS

Using a single institution IRB-approved prospective database, patients undergoing complex abdominal wall reconstruction from 2013 to 2021 were identified. Patients with AKI were compared to controls and preoperative and intraoperative characteristics were evaluated. Multivariate analysis was utilized to identify factors associated with development of AKI.

RESULTS

297 patients were reviewed, 21.2 % (n = 63 patients) had AKI. Patients with AKI had a greater decrease in postoperative GFR to preoperative GFR (40.5% vs 18.3%, p <0.0001). Factors associated with AKI included ASA score >2 (odds ratio (OR) = 2.10, [1.50; 5.12], p = 0.02), HTN (OR = 2.05, [1.05; 4.0], p = 0.04), higher baseline Cr (OR = 5.98, [2.56; 13.98], p <0.0001), and diabetes (OR = 0.135, [0.0275; 0.666], p = 0.01). Operative time was longer in patients who developed AKI [average 400 min (range: 278-510 min) vs 310 min (range: 260-374 min), p = 0.04] and was an independent predictor of developing AKI (OR = 319.59, [137.25; 744.65], p <0.0001).

DISCUSSION

Preoperative identification of patients with medical comorbidities undergoing elective complex abdominal wall reconstruction continues to be imperative to improve outcomes. This study demonstrates that perioperative management for high risk patients requires flexibility, including potential adjustments to enhanced recovery after surgery protocols in order to adequately address the risks for AKI.

Acute Kidney Injury After Large Ventral Hernia Repair Requiring Transversus Abdominis Release

BACKGROUND

Acute kidney injury (AKI) is a known postoperative complication of open ventral hernia repair contributing to increased costs, hospital length of stay, and mortality. The aim of this study was to identify whether the muscle injury that occurs in a posterior separation of components via transversus abdominis release (TAR) contributes to a higher incidence of postoperative AKI.

METHODS

A retrospective cohort study of patients who underwent open retrorectus ventral hernia repair with and without TAR at a single institution between 2012 and 2019 was performed. Patients who underwent a separation of components via either unilateral or bilateral transversus abdominis release were compared to those who did not undergo TAR as part of their hernia repair (non-TAR). The outcome of interest was the development of postoperative AKI. Acute kidney injury was defined as an increase in creatinine of greater than 50% of the preoperative baseline. Univariate and multivariate analyses were performed to determine the influence of TAR on the development of AKI.

RESULTS

There were 523 patients who met inclusion criteria, of which 159 (30.4%) had a TAR as part of their retrorectus hernia repair. No differences were found in preoperative characteristics between the TAR and non-TAR group including age, gender, history of kidney disease, or history of diabetes. By contrast, the TAR group had significantly greater median estimated blood loss (100 mL vs 75 mL, P < .01), mean positive intraoperative fluid balance (2255 mL vs 1887 mL, P < .01), and operative duration (321 min vs 269 min, P < .001). The rate of AKI in the TAR group was 11% (n = 18) vs 6% (n = 23, P = .0503) in the non-TAR group. On multivariate analysis controlling for patient characteristics and intraoperative factors, TAR was the only factor with a significantly increased odds of AKI (OR 1.97, 95% CI 0.994-3.905, P = .0521).

CONCLUSIONS

In patients with large ventral hernias requiring retrorectus repair, performing a TAR is associated with a nearly 2-fold increase in the development of postoperative AKI. These findings suggest that these patients should be optimized perioperatively with emphasis on fluid resuscitation, limiting nephrotoxic medications and monitoring urine output.

RvD1 Attenuated Susceptibility to Ischemic AKI in Diabetes by Downregulating Nuclear Factor-κ B Signal and Inhibiting Apoptosis

Background

Acute kidney injury (AKI), when occurring in diabetic kidney disease (DKD), is known to be more severe and difficult to recover from. Inflammation and apoptosis may contribute to the heightened sensitivity of, and non-recovery from, AKI in patients with DKD. Resolvin D1 (RvD1) is a potent lipid mediator which can inhibit the inflammatory response and apoptosis in many diseases. However, it has been reported that the RvD1 levels were decreased in diabetes, which may explain why DKD is more susceptible to AKI.

Methods

For animal experiments, diabetic nephropathy (DN) mice were induced by streptozotocin (STZ) injection intraperitoneally. Renal ischemia–reperfusion was used to induce AKI. Blood urea nitrogen (BUN) and serum creatinine were determined using commercial kits to indicate renal function. Renal apoptosis was examined by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. Real-time polymerase chain reaction (PCR) was used to detect the marker of inflammatory response. Western blot was used to detect the expression of nuclear factor-κB (NF-κB)-related proteins. For clinical study, 12 cases diagnosed with DKD were enrolled in this study, and an equal number of non-diabetic renal disease patients (NDKD) were recruited as a control group. The serum RvD1 in DKD or NDKD patients were detected through an ELISA kit.

Results

In clinical study, we found that the serum RvD1 levels were decreased in DKD patients compared to those in NDKD patients. Decreased serum RvD1 levels were responsible for the susceptibility to ischemic AKI in DKD patients. In animal experiments, both the serum RvD1 and renal ALX levels were downregulated. RvD1 treatment could ameliorate renal function and histological damage after ischemic injury in DN mice. RvD1 treatment also could inhibit the inflammatory response. Di-tert-butyl dicarbonate (BOC-2) treatment could deteriorate renal function and histological damage after ischemic injury in non-diabetic mice. RvD1 could inhibit the NF-κB activation and suppress inflammatory response mainly by inhibiting NF-κB signaling.

Conclusion

RvD1 attenuated susceptibility to ischemic AKI in diabetes by downregulating NF-κB signaling and inhibiting apoptosis. Downregulated serum RvD1 levels could be the crucial factor for susceptibility to ischemic AKI in diabetes.

AKI on CKD: heightened injury, suppressed repair, and the underlying mechanisms

Acute kidney injury (AKI) and chronic kidney disease (CKD) are interconnected. Although AKI-to-CKD transition has been intensively studied, the information of AKI on CKD is very limited. Nonetheless, AKI, when occurring in patients with CKD, is known to be more severe and difficult to recover. CKD is associated with significant changes in cell signaling in kidney tissues, including the activation of transforming growth factor-β, p53, hypoxia-inducible factor, and major developmental pathways. At the cellular level, CKD is characterized by mitochondrial dysfunction, oxidative stress, and aberrant autophagy. At the tissue level, CKD is characterized by chronic inflammation and vascular dysfunction. These pathologic changes may contribute to the heightened sensitivity of, and nonrecovery from, AKI in patients with CKD.

Causal relationship between hypoalbuminemia and acute kidney injury

Our meta-analysis published in 2010 provided evidence that low levels of serum albumin (hypoalbuminemia) are a significant independent predictor of acute kidney injury (AKI) and death following AKI. Since then, a large volume of additional data from observational clinical studies has been published further evaluating the relationship between serum albumin and AKI occurrence. This is an updated review of the literature to re-evaluate the hypothesis that hypoalbuminemia is independently associated with increased AKI risk. Eligible studies published from September 2009 to December 2016 were sought in PubMed (MEDLINE) and forty-three were retained, the great majority being retrospective observational cohort studies. These included a total of about 68000 subjects across a diverse range of settings, predominantly cardiac surgery and acute coronary interventions, infectious diseases, transplant surgery, and cancer. Appraisal of this latest data set served to conclusively corroborate and confirm our earlier hypothesis that lower serum albumin is an independent predictor both of AKI and death after AKI, across a range of clinical scenarios. The body of evidence indicates that hypoalbuminemia may causally contribute to development of AKI. Furthermore, administration of human albumin solution has the potential to prevent AKI; a randomized, controlled study provides evidence that correcting hypoalbuminemia may be renal-protective. Therefore, measurement of serum albumin to diagnose hypoalbuminemia may help identify high-risk patients who may benefit from treatment with exogenous human albumin. Multi-center, prospective, randomized, interventional studies are warranted, along with basic research to define the mechanisms through which albumin affords nephroprotection.

A BMI >35 does not protect patients undergoing cardiac bypass surgery from red blood cell transfusion

The effect of obesity on allogeneic intraoperative blood product transfusion in patients undergoing coronary artery bypass graft surgery (CABG) is poorly understood. We analyzed the influence of obesity on the risk of intraoperative red blood cell (RBC) transfusion among 45,200 consecutive non-reoperative CABG procedures from a multi-institutional perfusion database. A body mass index (BMI) in obese I category was associated with a 9.9% decrease in transfusion risk (p<0.05). Compared to patients with a normal BMI, obese I and obese III patients do not have any change in the relative risk of RBC transfusion. Overweight and mild obesity have a protective role in reducing intraoperative blood transfusion during cardiopulmonary bypass (CPB) surgery. However, logistic regression analysis showed that much of the observed reduction in transfusion rates for obese patients can be accounted for by other known confounds. The lack of a linear effect of increasing BMI on blood transfusion risk is a novel finding and warrants further investigation.