Impact of postoperative acute kidney injury in patients undergoing major gastrointestinal surgery on 1-year survival and renal outcomes: a national multicentre cohort study

Intraoperative fluid management is not predictive of AKI in major pancreatic surgery: a retrospective cohort study

BACKGROUND

Pancreatic surgery is associated with a significant risk for acute kidney injury (AKI) and clinically relevant postoperative pancreatic fistula (CR-POPF). This investigation evaluated the impact of intraoperative volume administration, vasopressor therapy, and blood pressure management on the primary outcome of AKI and the secondary outcome of a CR-POPF after pancreatic surgery.

METHODS

This retrospective single-center cohort investigated 200 consecutive pancreatic surgeries (January 2018-December 2021). Patients were categorized for the presence/absence of AKI (Kidney Disease Improving Global Outcomes) and CR-POPF. After univariate analysis, multivariable models were constructed to control for the univariate cofactor differences in the primary and secondary outcomes.

RESULTS

AKI was identified in 20 patients (10%) with significant univariate differences in demographics (body mass index and gender), comorbidities, indices of chronic renal insufficiency, and an increased AKI Risk score. Surgical characteristics, intraoperative fluid, vasopressor, and blood pressure management were similar in patients with and without AKI. Patients with AKI had increased blood loss, lower urine output, and packed red blood cell administration. After multivariate analysis, male gender (OR = 7.9, 95% C.I. 1.8-35.1) and the AKI Risk score (OR = 6.3, 95% C.I. 2.4-16.4) were associated with the development of AKI (p < 0.001). Intraoperative and postoperative volume, vasopressor administration, and intraoperative hypotension had no significant impact in the multivariate analysis. CR-POPF occurred in 23 patients (11.9%) with no significant contributing factors in the multivariate analysis. Patients who developed AKI or a CR-POPF had an increase in surgical complications, length of stay, discharge to a skilled nursing facility, and mortality.

CONCLUSION

In this analysis, intraoperative volume administration, vasopressor therapy, and a blood pressure < 55 mmHg for more than 10 min were not associated with an increased risk of AKI. After multivariate analysis, male gender and an elevated AKI Risk score were associated with an increased likelihood of AKI.

Heterogeneity in the definition of major adverse kidney events: a scoping review

Acute kidney injury (AKI) is associated with persistent renal dysfunction, the receipt of dialysis, dialysis dependence, and mortality. Accordingly, the concept of major adverse kidney events (MAKE) has been adopted as an endpoint for assessing the impact of AKI. However, applied criteria or observation periods for operationalizing MAKE appear to vary across studies. To evaluate this heterogeneity for MAKE evaluation, we performed a systematic scoping review of studies that employed MAKE as an AKI endpoint. Four major academic databases were searched, and we identified 122 studies with increasing numbers over time. We found marked heterogeneity in applied criteria and observation periods for MAKE across these studies, with some even lacking a description of criteria. Moreover, 13 different observation periods were employed, with 30 days and 90 days as the most common. Persistent renal dysfunction was evaluated by estimated glomerular filtration rate (34%) or serum creatinine concentration (48%); however, 37 different definitions for this component were employed in terms of parameters, cut-off criteria, and assessment periods. The definition for the dialysis component also showed significant heterogeneity regarding assessment periods and duration of dialysis requirement (chronic vs temporary). Finally, MAKE rates could vary by 7% [interquartile range: 1.7-16.7%] with different observation periods or by 36.4% with different dialysis component definitions. Our findings revealed marked heterogeneity in MAKE definitions, particularly regarding component assessment and observation periods. Dedicated discussion is needed to establish uniform and acceptable standards to operationalize MAKE in terms of selection and applied criteria of components, observation period, and reporting criteria for future trials on AKI and related conditions.

Preoperative geriatric nutritional risk index and neutrophil-to-lymphocyte ratio relate to postoperative acute kidney injury in elderly patients undergoing laparoscopic abdominal surgery

Background

Acute kidney injury (AKI) poses a significant concern in elderly patients undergoing laparoscopic abdominal surgery due to increased vulnerability arising from aging, comorbidities, and surgery-related factors. Early detection and intervention are crucial for mitigating short- and long-term consequences. This study aims to investigate the correlation between preoperative Geriatric Nutritional Risk Index (GNRI), neutrophil-to-lymphocyte ratio (NLR), and the occurrence of postoperative AKI in elderly patients undergoing laparoscopic abdominal surgery, as well as to assess the predictive value of their combined detection for postoperative AKI.

Methods

A retrospective study involving 347 elderly patients (aged 60 years or older) undergoing laparoscopic abdominal surgery explored the relationship between preoperative GNRI, NLR, and postoperative AKI. GNRI was calculated based on serum albumin and body weight ratios, while NLR was derived from preoperative blood tests.

Results

The combined GNRI and NLR test demonstrated superior predictive value (area under the curve [AUC] = 0.87) compared to individual markers. Multivariate logistic analysis identified age, American Society of Anesthesiologists (ASA) grade, comorbidities, preoperative GNRI, and NLR as independent risk factors for AKI. Correlation analysis affirmed a negative correlation between preoperative GNRI and AKI severity, and a positive correlation between preoperative NLR and AKI severity.

Conclusion

The preoperative GNRI and NLR have clinical values in predicting postoperative AKI in elderly patients undergoing laparoscopic abdominal surgery.

Preoperative urine neutrophil gelatinase-associated lipocalin predicts mortality in colorectal cancer patients after laparoscopic surgery: A single-center study

Purpose

To determine the rate of acute kidney injury (AKI) after laparoscopic colorectal cancer (CRC) surgery and the predictive value of urine neutrophil gelatinase-associated lipocalin (uNGAL) for postoperative AKI and mortality during 3 years of follow-up.

Methods

A total of 216 CRC patients who had undergone laparoscopic surgery were included in our study. We divided all patients into two groups, including group 1 (n = 31) with postoperative AKI and group 2 (n = 185) without postoperative AKI. Urine NGAL was measured using the ELISA technique. Clinical and laboratory data were collected the day before surgery. Postoperative AKI included events occurring within 7 days of the index operation, and mortality was obtained during 3 years of follow-up.

Results

The ratio of postoperative AKI was 14.35% (31/216 patients). The urine NGAL level in group 1 was significantly higher than in group 2, p < 0.001. At cut-off value = 14.94 ng/mL, uNGAL has a predictive value for AKI (area under the curve [AUC] = 0.858, p < 0.001). After 3 years of follow-up, the total mortality rate was 7.9%. The mortality rate in group 1 (45.2%) was significantly higher than in group 2 (1.6%) with p < 0.001). At cut-off value = 19.85 ng/mL, uNGAL has a predictive value for mortality (AUC = 0.941, p < 0.001).

Conclusions

The rate of acute kidney injury after laparoscopic CRC surgery was 14.35%. Preoperative urine NGAL has a good predictive value for postoperative acute kidney injury and mortality during 3 years of follow-up.

Long-term healthcare use after postoperative complications: an analysis of linked primary and secondary care routine data

Background

Postoperative complications are associated with reduced long-term survival. We characterise healthcare use changes after sentinel postoperative complications.

Methods

We linked primary and secondary care records of patients undergoing elective surgery at four East London hospitals (2012-7) with at least 90 days follow-up. Complication codes (wound infection, urinary tract infection, pneumonia, new stroke, and new myocardial infarction) recorded within 90 days of surgery were identified from primary or secondary care. Outcomes were change in healthcare contact days in the 2 yr before and after surgery, and 2 yr mortality. We report rate ratios (RaR) with 95% confidence intervals and adjusted for baseline healthcare use and confounders using negative binomial regression.

Results

We included 49 913 patients (median age 49 yr [inter-quartile range {IQR}: 34-64]), 27 958 (56.0%) were female. Amongst 3883 (7.8%) patients with complications (median age 58 [IQR: 43-72]), there were 18.4 days per year in contact with healthcare before surgery and 25.3 days after surgery (RaR: 1.38 [1.37-1.39]). Patients without complications (median age 48 [IQR: 33-63]) had 12.3 days per year in contact with healthcare before surgery and 14.0 days after surgery (RaR: 1.14 [1.14-1.15]). The adjusted incidence rate ratio of days in contact with healthcare associated with complications was 1.67 (1.49-1.87). More patients (391; 10.1%) with complications died within 2 yr than those without (1428; 3.1%).

Conclusions

Patients with postoperative complications are older with greater healthcare use before surgery. However, their absolute and relative increases in healthcare use after surgery are greater than patients without complications.

The effect of prehabilitation on the postoperative outcomes of patients undergoing colorectal surgery: A systematic review and meta-analysis

Study objective

Prehabilitation is analogous to marathon training and includes preoperative preparation for exercise, as well as nutrition and psychology. However, evidence-based recommendations to guide prehabilitation before colorectal surgery are limited. We aimed to evaluate the effect of prehabilitation on the postoperative outcomes of patients undergoing colorectal surgery.

Design

This study is a systematic review and meta-analysis.

Methods

The PubMed, Embase, and Cochrane databases were searched for studies reporting the effect of prehabilitation strategies versus standard care or rehabilitation in patients undergoing colorectal surgery. The primary outcomes were overall postoperative complications and length of hospital stay (LOS), and the secondary outcome was functional capacity (measured using the 6-min walk test [6MWT]) at 4 and 8 weeks after surgery.

Main results

Fifteen studies with 1,306 participants were included in this meta-analysis. The results showed no significant reduction in the number of overall postoperative complications (risk ratio = 1.02; 95% confidence interval [CI] = 0.79-1.31; p = 0.878) or LOS (standardized mean difference = 0.04; 95% CI = -0.11 to 0.20; p = 0.589) in patients who underwent colorectal surgery with or without prehabilitation strategy. Additionally, there were no significant differences in the functional capacity estimated using the 6MWT at 4 and 8 weeks postoperatively.

Conclusions

Prehabilitation did not significantly affect the number of postoperative complications, LOS, or functional capacity of patients undergoing colorectal surgery. Whether prehabilitation should be recommended deserves further consideration.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=290108, identifier CRD42021290108.

Validation of the OAKS prognostic model for acute kidney injury after gastrointestinal surgery

Background

Postoperative acute kidney injury (AKI) is a common complication of major gastrointestinal surgery with an impact on short- and long-term survival. No validated system for risk stratification exists for this patient group. This study aimed to validate externally a prognostic model for AKI after major gastrointestinal surgery in two multicentre cohort studies.

Methods

The Outcomes After Kidney injury in Surgery (OAKS) prognostic model was developed to predict risk of AKI in the 7 days after surgery using six routine datapoints (age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker). Validation was performed within two independent cohorts: a prospective multicentre, international study (‘IMAGINE’) of patients undergoing elective colorectal surgery (2018); and a retrospective regional cohort study (‘Tayside’) in major abdominal surgery (2011–2015). Multivariable logistic regression was used to predict risk of AKI, with multiple imputation used to account for data missing at random. Prognostic accuracy was assessed for patients at high risk (greater than 20 per cent) of postoperative AKI.

Results

In the validation cohorts, 12.9 per cent of patients (661 of 5106) in IMAGINE and 14.7 per cent (106 of 719 patients) in Tayside developed 7-day postoperative AKI. Using the OAKS model, 558 patients (9.6 per cent) were classified as high risk. Less than 10 per cent of patients classified as low-risk developed AKI in either cohort (negative predictive value greater than 0.9). Upon external validation, the OAKS model retained an area under the receiver operating characteristic (AUC) curve of range 0.655–0.681 (Tayside 95 per cent c.i. 0.596 to 0.714; IMAGINE 95 per cent c.i. 0.659 to 0.703), sensitivity values range 0.323–0.352 (IMAGINE 95 per cent c.i. 0.281 to 0.368; Tayside 95 per cent c.i. 0.253 to 0.461), and specificity range 0.881–0.890 (Tayside 95 per cent c.i. 0.853 to 0.905; IMAGINE 95 per cent c.i. 0.881 to 0.899).

Conclusion

The OAKS prognostic model can identify patients who are not at high risk of postoperative AKI after gastrointestinal surgery with high specificity.

Presented to Association of Surgeons in Training (ASiT) International Conference 2018 (Edinburgh, UK), European Society of Coloproctology (ESCP) International Conference 2018 (Nice, France), SARS (Society of Academic and Research Surgery) 2020 (Virtual, UK).