Elevated Preoperative Serum Creatinine Research Articles

Morbidität und Mortalität nach NSCLC-Operationen bei älteren Patienten: Individualisierte Risikobewertung notwendig

Background: Reports from case series suggest that operative outcomes are comparable amongst different age groups following surgery with curative intent for non-small cell lung cancer (NSCLC). The purpose of this study was to compare morbidity and mortality after NSCLC surgery in older patients (≥ 75 years) versus younger patients (< 75 years) and identify independent predictive risk factors. Methods: We identified 2015 patients with postoperative stages IA to IIIA according to AJCC/UICC 7th edition who had undergone NSCLC surgery with curative intent at a single specialized lung cancer center from January 2010 to December 2015. A matched-pair analysis was performed on 227 older patients and corresponding 227 younger patients. Short-term surgical outcomes were postoperative morbidity, length of hospital stay, 30-day and 90-day mortality. Long-term operative outcomes were disease-free and overall survival. Results: 454 patients were included in the matched-pair analysis. 36% of younger patients developed postoperative complications versus 42% in older patients (p = 0.163). Age was not significantly associated with the occurrence of postoperative complications. Median length of hospital stay was 14 days in older patients and 13 days in younger patients (p = 0.185). 90-day mortality was 2.2% in younger patients compared to 4% in older patients (p = 0.424). In patients aged 75 and older impaired performance status (ECOG ≥ 1) was associated with decreased overall survival (HR = 2.15, CI 1.34–3.46), as were preoperative serum C-reactive protein / albumin ratio ≥ 0.3 (HR = 1.95, CI 1.23–3.11) and elevated preoperative serum creatinine levels ≥ 1.1 mg/dl (HR = 1.84, CI 1.15–2.95). In the younger cohort male sex (HR = 2.26, CI 1.17–4.36), postoperative stage III disease (HR 4.61, CI 2.23–9.54) and preoperative anemia (hemoglobin < 12 g/dl) (HR 2.09, CI 1.10–3.96) were associated with decreased overall survival.

Predicting prolonged length of stay following revision total knee arthroplasty: A national database analysis using machine learning models

BackgroundAs the number of revision total knee arthroplasty (TKA) continues to rise, close attention has been paid to factors influencing postoperative length of stay (LOS). The aim of this study is to develop generalizable machine learning (ML) algorithms to predict extended LOS following revision TKA using data from a national database. Methods23,656 patients undergoing revision TKA between 2013 and 2020 were identified using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Patients with missing data and those undergoing re-revision or conversion from unicompartmental knee arthroplasty were excluded. Four ML algorithms were applied and evaluated based on their (1) ability to distinguish between at-risk and not-at-risk patients, (2) accuracy, (3) calibration, and (4) clinical utility. ResultsAll four ML predictive algorithms demonstrated good accuracy, calibration, clinical utility, and discrimination, with all models achieving a similar area under the curve (AUC) (AUCLR=AUCRF=AUCHGB=0.75, AUCANN=0.74). The most important predictors of prolonged LOS were found to be operative time, preoperative diagnosis of sepsis, and body mass index (BMI). ConclusionsML models developed in this study demonstrated good performance in predicting extended LOS in patients undergoing revision TKA. Our findings highlight the importance of utilizing nationally representative patient data for model development. Prolonged operative time, preoperative sepsis, BMI, and elevated preoperative serum creatinine and BUN were noted to be significant predictors of prolonged LOS. Knowledge of these associations may aid with patient-specific preoperative planning, discharge planning, patient counseling, and cost containment with revision TKA.

Peri- and postoperative morbidity and mortality in older patients with non-small cell lung cancer: a matched-pair study

BackgroundReports from case series suggest that operative outcomes are comparable amongst different age groups following surgery with curative intent for non-small cell lung cancer (NSCLC). The purpose of this study was to compare morbidity and mortality after NSCLC surgery in older patients (≥ 75 years) versus younger patients (< 75 years) and identify independent predictive risk factors.MethodsWe identified 2015 patients with postoperative stages IA to IIIA according to AJCC/UICC 7th edition who had undergone NSCLC surgery with curative intent at a single specialized lung cancer center from January 2010 to December 2015. A matched-pair analysis was performed on 227 older patients and corresponding 227 younger patients. Short-term surgical outcomes were postoperative morbidity, length of hospital stay, 30-day and 90-day mortality. Long-term operative outcomes were disease-free and overall survival.Results454 patients were included in the matched-pair analysis. 36% of younger patients developed postoperative complications versus 42% in older patients (p = 0.163). Age was not significantly associated with the occurrence of postoperative complications. Median length of hospital stay was 14 days in older patients and 13 days in younger patients (p = 0.185). 90-day mortality was 2.2% in younger patients compared to 4% in older patients (p = 0.424). In patients aged 75 and older impaired performance status (ECOG ≥ 1) was associated with decreased overall survival (HR = 2.15, CI 1.34–3.46), as were preoperative serum C-reactive protein / albumin ratio ≥ 0.3 (HR = 1.95, CI 1.23–3.11) and elevated preoperative serum creatinine levels ≥ 1.1 mg/dl (HR = 1.84, CI 1.15–2.95). In the younger cohort male sex (HR = 2.26, CI 1.17–4.36), postoperative stage III disease (HR 4.61, CI 2.23–9.54) and preoperative anemia (hemoglobin < 12 g/dl) (HR 2.09, CI 1.10–3.96) were associated with decreased overall survival.ConclusionsLung resection for NSCLC in older patients is associated with postoperative morbidity and mortality comparable to those of younger patients. In older patients, physical activity, comorbidities and nutritional status are related to survival and should influence the indication for surgery rather than age alone.

The View Outside of the Box: Reporting Outcomes Following Radical Cystectomy Using Pentafecta From a Multicenter Retrospective Analysis.

We aimed at characterization of the patients undergoing radical cystectomy (RC) using the prognostic model (a modified pentafecta). In the multicenter retrospective study, we enrolled 304 patients with bladder cancer (pTis-4N0-2M0) who underwent RC between 2015 and 2020 in experienced centers. The definition of the pentafecta was as follows: no Clavien–Dindo grade III–V complications at 90 days and no long-term complications related to urinary diversion <12 months, negative surgical margins, ≥10 lymph nodes (LNs) resected, and no recurrence ≤12 months. RC-pentafecta achievement rate was 22% (n = 67), varying from 47% to 88% attainment rate for different pentafecta components, and was the lowest for sufficient LN yield. Both 12-month recurrence-free survival (RFS) and cancer-specific mortality were compromised in pentafecta failers compared with achievers (57.8% vs. 100% and 33.8% vs. 1.5%, respectively). The following were identified as crucial predictors of RC pentafecta achievement: modality of the surgery, type of urinary diversion, histological type of bladder cancer, advanced staging, and elevated preoperative serum creatinine. In conclusion, we found that the pentafecta achievement rate was low even in high-volume centers in patients undergoing cystectomy. The complexity of the procedure directly influenced the attainment rate, which in turn led to an increase in cancer-specific mortality rate among the pentafecta failers.

Risk factors of postoperative ileus following laparoscopic radical cystectomy and developing a points-based risk assessment scale.

BackgroundPostoperative ileus (POI) is one of the most common complications after laparoscopic radical cystectomy (LRC). Albeit its high incidence, its risk factors are obscure, and few studies have attempted to explore them. Meanwhile, risk-assessing tools for predicting its happening are lacking.MethodsClinical data of 197 patients who underwent LRC between March 2014 and October 2019 were retrospectively collected. All cases of POI were identified and double-checked. Data pertaining to the following categories were extracted as well: patients’ general characteristics, preoperative laboratory tests results and preparations, intraoperative and postoperative general items, pathological results. The correlation between candidate risk factors and ileus was analyzed by multivariable binary logistic regression. Clinical and pathophysiological explanations for those results were explored. Finally, a points-based prediction model was developed and validated for predicting the happening of POI.ResultsA total of 63 out of 197 patients (31.98%) suffered from POI. Multivariate logistic regression analysis showed chronic constipation, increased dosage of laxative, elevated preoperative serum creatinine level, delayed postoperative ambulation, intestine-related urine derivations were statistically significant for developing POI (P<0.05). No significant differences were found between POI and age, gender, body mass index (BMI), antibiotics, hypertension, diabetes, smoking, hard-drinking, preoperative hemoglobin level, preoperative albumin level, history of previous abdominal surgery, surgery time, intraoperative blood loss, blood transfusion, tumor size, lymph nodes yields, TNM staging and intensive care unit hospitalization. An external cohort had been used for testing the validation of the assessment scale, and the results were promising.ConclusionsEarly recognition is of great importance in protecting vulnerable patients from developing POI, knowing the above-mentioned risk factors and using the assessment scale should help to screen them better. Cases from diverse backgrounds might contribute to a more accurate and complete scale.

Results of day-case ureterorenoscopy (DC-URS) for stone disease: prospective outcomes over 4.5\xa0years

PurposeTo investigate the prospective outcomes of day-case ureterorenoscopy (DC-URS) for stone disease. With the rising prevalence of stone disease in the face of finite resources, there is increasing pressure to undertake procedures as a day case avoiding in-patient stay. There are a limited number of studies reporting on the feasibility of ureteroscopy as a day-case procedure. This study aimed to investigate the prospective outcomes and predictors precluding to DC-URS for stone disease in patients treated in our university teaching hospital.Materials and methodsBetween March 2012 and July 2016, consecutive cases of adult stone ureteroscopy performed or supervised by a single surgeon were recorded in a prospective database. Patients underwent pre-operative counselling in a specialist stone clinic and were admitted to a dedicated ‘Surgical day unit’ on the day of surgery. A standardised anaesthetic protocol was adhered to in all cases. Data on patient demographics, stone parameters, pre-operative assessment, operative details, length of stay, stone-free rate and complication rates were collected and analysed.ResultsA total of 544 consecutive adult ureteroscopy for stone disease were conducted over the study period with a day-case rate of 77.7%. Thirty-nine percent of failed day-case ureteroscopy were due to late completion of ureteroscopy and due to associated social circumstances of patients. The mean stone size, operating time duration and post-operative stent insertion rates for DC-URS patients were 14 mm, 46 min and 96.5%, respectively. Post-operatively, the mean stone-free rate (SFR), unplanned re-admissions and complications for DC-URS patients were 95, 4 and 4%, respectively. A higher failure of DC-URS was related to patient’s age (p = 0.003), positive pre-operative urine culture (p < 0.001), elevated pre-operative serum creatinine (p < 0.001) and higher mean operating time (p < 0.02).ConclusionBased on our results, a day-case ureteroscopy rate of nearly 78% can be achieved. With its acceptable complication rate, and low re-admission rates, DC-URS is a safe and feasible option in a majority of patients with stone disease.

Invited Commentary

Invited Commentary

Acute Renal Failure Secondary to Rhabdomyolysis as a Complication of Major Urological Surgery: The Experience of a High-Volume Urological Center

Objective: The aim of this study was to determine the incidence of acute renal failure secondary to rhabdomyolysis (ARFSR) as a complication of major urological surgery (MUS), as well as to describe the clinical characteristics and identify possible risk and protective factors. Subjects and Methods: Cases of ARFSR due to MUS between January 1997 and August 2011 were identified using the institutional database. The incidence was estimated and the clinical characteristics were analyzed using simple scatterplot graphs to identify possible risk and protective factors. Results: In this period, 14,337 MUS procedures were performed, in which 4 cases suffered from ARFSR (the incidence rate was 0.03%). The incidence rates after radical cystectomy and urethroplasty were 0.26% (3/1,175 cases) and 0.15% (1/651 cases), respectively. No case of rhabdomyolysis was reported among the patients who underwent other major surgical procedures. Two patients required dialysis, and all 4 patients recovered to their baseline renal function at an average of 11 days (7-17) with the appropriate treatment. Male gender, younger age, lower ASA score, prolonged operative time, high body mass index, elevated preoperative serum creatinine and estimated blood loss were possible risk factors for developing ARFSR due to MUS. We found that a higher intraoperative administered volume was a possible protective factor. The operative position and type of surgery seemed to play minor roles. Early diagnosis and treatment possibly leads to an improved outcome. Conclusion: In our study, ARFSR due to MUS was a rare entity and had a good prognosis. It was more frequent as a complication of radical cystectomy. Further studies are required to confirm our findings.

92 Transcatheter Aortic Valve Implantation in Patients with Pre-existing Chronic Kidney Disease

<h3>Introduction</h3> Transcatheter aortic valve implantation (TAVI) for symptomatic severe aortic stenosis is being increasingly undertaken in a more complex cohort of patients with multiple co-morbidities. Whilst it is a safe alternative to surgical aortic valve replacement in the high-risk population, these co-morbidities are often excluded from large trials. We sought to investigate the effect of chronic kidney disease (CKD) on morbidity and mortality following TAVI including patients on haemodialysis. <h3>Methods</h3> We performed a <i>post hoc</i> analysis of a prospectively collected registry of all patients undergoing TAVI at our centre between 2008–12. Patients were grouped into a ‘CKD’ or a ‘No-CKD’ group (with CKD defined as patients with a baseline estimated glomerular filtration rate (eGFR) &lt;60 mL/min/1.73 m²). Patients requiring prior haemodialysis were included in the mortality and morbidity analysis but excluded from acute kidney injury (AKI) analysis. AKI was defined as set out in the recently updated Valve Academic Research Consortium (VARC-2) criteria. The TAVI procedure was performed using Medtronic CoreValve and Edward LifeSciences Sapien valves and implanted using the femoral (percutaneous and surgical cut-down), axillary, subclavian, transapical and transaortic routes. <h3>Results</h3> 118 consecutive patients underwent TAVI with 63 considered to have significant pre-existing ‘CKD’ whilst 55 did not (‘No-CKD’). 4 patients required either chronic or acute renal replacement therapy (RRT) prior to the procedure. The mean age of the population was 81.3 ± 7.7 years (mean±SD), 57.6% were males, 22.0% diabetic and the mean Logistic EuroSCORE was 20.9 ± 14.9%. The baseline eGFR was 46.8 ± 8.7 and 77.9 ± 16.5 µmol/L in the CKD and No-CKD groups respectively. Other than renal parameters, no significant baseline differences existed between the two groups. TAVI implantation predominantly involved the Medtronic CoreValve (90%) and the percutaneous transfemoral route (76%). CKD patients received less contrast than No-CKD patients (151.6 ± 62.4 vs. 195.0 ± 56.8 mL, <i>p &lt; 0</i>.001). Following TAVI, in CKD and No-CKD patients respectively; AKI occurred in 23.7% and 14.5% (<i>p = 0</i>.455) and RRT was necessary in 8.5% and 3.6% (relative risk [95% CI] = 2.33 [0.47–11.5], <i>p = 0</i>.440); 30-day mortality rates were 6.3% and 1.8% (<i>p = 0</i>.370) and 1-year mortality rates were 17.5% and 18.2% (<i>p = 0</i>.919). Patients who developed AKI had a significantly increased risk of 30-day (12.5% vs. 1.1%, <i>p = 0</i>.029) mortality. We found the presence of diabetes (odds ratio (OR) [95% CI] = 4.58 [1.58–13.3], <i>p = 0</i>.005) and elevated baseline serum creatinine (OR [95% CI] = 1.02 [1.00–1.03], <i>p = 0</i>.026) to independently predict AKI by multivariate analysis. <h3>Conclusions</h3> TAVI is a safe, acceptable treatment for patients with pre-existing CKD, however caution must be exercised, particularly in patients with pre-existing diabetes mellitus and elevated pre-operative serum creatinine levels as this confers a greater risk of AKI development.

Transcatheter aortic valve implantation in patients with pre-existing chronic kidney disease

BackgroundWe investigated the effect of chronic kidney disease (CKD) on morbidity and mortality following transcatheter aortic valve implantation (TAVI) including patients on haemodialysis, often excluded from randomised trials. Methods and resultsWe performed a retrospective post hoc analysis of all patients undergoing TAVI at our centre between 2008 and 2012. 118 consecutive patients underwent TAVI; 63 were considered as having (CKD) and 55 not having (No-CKD) significant pre-existing CKD, (defined as estimated glomerular filtration rate (eGFR)<60mL/min/1.73m2). Chronic haemodialysis patients (n=4) were excluded from acute kidney injury (AKI) analysis. Following TAVI, in CKD and No-CKD patients respectively, AKI occurred in 23.7% and 14.5% (p=0.455) and renal replacement therapy (RRT) was necessary in 8.5% and 3.6% (relative risk (RR) [95% CI]=2.33 [0.47–11.5], p=0.440); 30-day mortality rates were 6.3% and 1.8% (p=0.370); and 1-year mortality rates were 17.5% and 18.2% (p=0.919). Patients who developed AKI had a significantly increased risk of 30-day (12.5% vs. 1.1%, p=0.029) mortality. We found the presence of diabetes (odds ratio (OR) [95% CI]=4.58 [1.58–13.3], p=0.005) and elevated baseline serum creatinine (OR [95% CI]=1.02 [1.00–1.03], p=0.026) to independently predict AKI to statistical significance by multivariate analysis. ConclusionTAVI is a safe, acceptable treatment for patients with pre-existing CKD, however caution must be exercised, particularly in patients with pre-existing diabetes mellitus and elevated pre-operative serum creatinine levels as this confers a greater risk of AKI development, which is associated with increased short-term post-operative mortality.

Acute kidney injury based on KDIGO (Kidney Disease Improving Global Outcomes) criteria in patients with elevated baseline serum creatinine undergoing cardiac surgery.

IntroductionPreoperatively elevated serum creatinine (SCr) is considered an independent risk factor for morbidity and mortality after cardiac surgery. The aim of this study was to apply the Kidney Disease Improving Global Outcomes classification for acute kidney injury in a population of patients with preoperatively elevated serum creatinine who underwent cardiac surgery (coronary artery bypass grafting or cardiac valve surgery) and to evaluate the acute worsening of renal function as a predictor of 30-day mortality.MethodsThis was a single-center retrospective study that included patients from the Postoperative Cardiac Surgery Intensive Care Unit of the Hospital de Base, São José do Rio Preto Medical School. Demographics, type of surgery, laboratory data and pre, peri and postoperative data were obtained from a prospectively collected database. From January 2003 to June 2013, 2,878 patients underwent cardiac surgery, either coronary artery bypass grafting or cardiac valve surgery, at the Hospital de Base of São José do Rio Preto Medical School. Out of those, 918 showed elevated preoperative serum creatinine, with SCr > 1.30 mg/dL for men and > 1.00 mg/dL for women. Five hundred and forty nine patients (60%) undergoing coronary artery bypass grafting and 369 patients (40%) undergoing cardiac valve surgery. A Multivariate Cox Proportional Hazard Model (stepwise) was used to assess the relationship between AKI and mortality at 30 days.ResultsOut of the 918 patients studied, 391 (43%) had postoperative AKI: 318 (35%) had Kidney Disease Improving Global Outcomes stage 1, 27 (2.9%) had Kidney Disease Improving Global Outcomes stage 2, and 46 (5.0%) had Kidney Disease Improving Global Outcomes stage 3. Patients in every stage of acute kidney injury showed progressive increase in EuroSCORE values, 30-day mortality ratescardiopulmonary bypass duration, and intensive care length of stay. Among patients classified as Kidney Disease Improving Global Outcomes stage 3, 76% required dialysis with a 30-day mortality of 66%. The Cox proportional hazards model showed that the hazard ratio for 30-day mortality was 4.8 for Kidney Disease Improving Global Outcomes stage 1 patients, 13.5 for Kidney Disease Improving Global Outcomes stage 2 patients, and 20.8 for Kidney Disease Improving Global Outcomes stage 3 patients (P<0.001 for all). Subgroup analyses (coronary artery bypass grafting and cardiac valve surgery) had similar results.ConclusionIn this population, acute kidney injury based on the Kidney Disease Improving Global Outcomes criteria was a powerful predictor of 30-day mortality in patients with elevated preoperative serum creatinine who underwent cardiac surgery (coronary artery bypass grafting or cardiac valve surgery).

The Risk of Perioperative Bleeding in Patients With Chronic Kidney Disease

Worldwide, millions of patients with chronic kidney disease undergo surgery each year. Although chronic kidney disease increases the risk of bleeding in nonoperative settings, the risk of perioperative bleeding is less clear. We conducted a systematic review and meta-analysis to summarize existing information and quantify the risk of perioperative bleeding from chronic kidney disease. We screened 9376 citations from multiple databases for cohort studies published between 1990 and 2011. Studies that met our inclusion criteria included patients undergoing any major surgery, with a sample size of at least 100 patients with chronic kidney disease (as defined by the primary study authors with an elevated preoperative serum creatinine value or a low estimated glomerular filtration rate). Their outcomes had to be compared with a reference group of at least 100 patients without chronic kidney disease. Our primary outcomes were (1) receipt of perioperative blood transfusions and (2) need for reoperation for reasons of bleeding. Twenty-three studies met our criteria for review (20 cardiac surgery, 3 non-cardiac surgery). Chronic kidney disease was associated with a greater risk of requiring blood transfusion (7 studies in cardiac surgery, totaling 22,718 patients) and weighted incidence in patients with normal kidney function was 53% and in chronic kidney disease was 73%; pooled odds ratio, 2.7 (95% confidence interval, 2.1-3.4). After adjustment for relevant factors, the association remained statistically significant in 4 studies. Chronic kidney disease was associated with more reoperation for reasons of bleeding (14 studies in cardiac surgery, totaling 569,715 patients) and weighted incidence in patients with normal kidney function was 2.4% and in chronic kidney disease was 2.7%; pooled odds ratio, 1.6 (95% confidence interval, 1.3-1.8). However, after adjustment for relevant factors (as done in 5 studies), the association was no longer statistically significant. Chronic kidney disease is associated with perioperative bleeding but not bleeding that required reoperation. Further studies should stage chronic kidney disease with the modern system, better define bleeding outcomes, and guide intervention to improve the safety of surgery in this at-risk population.

Multifaceted Blood Conservation Stratergy Reduces Periopertative Transfusion Requirement in Cardiac Surgery

Fig. 1. Surgical progression of patient cohort. Discussion: Surgical outcomes of single ventricle palliation seem poor in patients with dextrocardia. Aggressive management of congenital AVVR could improve longterm prognosis (Fig. 1). http://dx.doi.org/10.1016/j.hlc.2013.03.053 2012 Poster Presentation/Panel 28 Multifaceted Blood Conservation Stratergy Reduces Periopertative Transfusion Requirement in Cardiac Surgery Benjamin M. Robinson1,4,∗, Waleed A. Ahmed1, William O’Regan2, Manish Jain1, Ajay Hirikannawar1, Hugh D. Wolfenden1, Bruce G. French1, Rebecca Dignan1,3 1Department of Cardiothoracic Surgery, Liverpool Hospital, Sydney, Australia 2 Department of Anaesthesia, Liverpool Hospital, Sydney, Australia A B S T R A C T S Heart, Lung and Circulation 481 2013;22:455–489 2012 ANZSCTS Annual Scientific Meeting 3 University of New South Wales Clinical School, Liverpool, Australia 4 The Baird Institute for Applied Heart and Lung Surgical Research, Sydney, Australia Introduction: This study aimed to evaluate the effect of a multifaceted blood conservation strategy on blood product transfusion rates in cardiac surgery. This strategy involved acute normovolaemic haemodilution, also known as autologous operative donation, low volume pump priming, retrograde autologous pump priming (RAPP) and theuse of the antifibrinolytic, tranexamic acid. Risk factors for transfusion were also evaluated. Methods: A retrospective analysis of 1582 consecutive cardiac surgery patients at Liverpool Hospital between January 2008 and June 2012 was performed. 473 patients made up the blood conservation group, commencing June 2011. Using propensity score methods, a matched cohort of historical controls was assembled. Multivariate logistic regression was used to determine the independence of risk factors for transfusion. Results:Themean age of patientswas 64.4. Themajority had coronary artery bypass grafting alone (63.1%) or single valve procedures (17.5%), while 39.6% of cases were non-elective. Increased age, prolonged cardiopulmonary bypass, elevated preoperative serum creatinine, previous cardiac surgery, low body surface area, urgent or emergency surgery and preoperative anti-platelet agent administration were independent risk factors for transfusion. The crude transfusion rates in theblood conservation groupand the remainder of the cohortwere 33.8% (95%CI; 29.5–38.1) and62.7% (95%CI; 59.9–65.6) respectively. There was a 27.4% (95% CI; 22.2–35.2) reduction in transfusion rate for the blood conservation cohort when compared to propensity score matched controls. Conclusions: A multifaceted blood conservation strategy combining antifibrinolytic use with changes in perfusion practice reduces perioperative blood product transfusion in cardiac surgery. http://dx.doi.org/10.1016/j.hlc.2013.03.054 2012 Poster Presentation/Panel 29 Management of the Empty Pleural Space with Balanced Chest Drainage to Prevent Post-Pneumonectomy Pul-

RR7. Improving Patient Selection for Limb Salvage versus Early BKA

Objectives: Advances in prosthetic technology have allowed below knee amputees an efficient and functional return to their pre-injury level of activity. Below knee amputation (BKA) can be a more functional option to limb salvage in select patients. Difficulty remains in patient selection. In order to improve patient selection for limb salvage versus early BKA, we reviewed our experience with BKAs and limb salvage to determine predictive variables for treatment success and ambulation. Methods: We performed a retrospective, institutional review boardapproved review of below knee amputations performed by the senior author between 2004 and 2011 in patients who ambulated pre-operatively. Results: 286 BKAs on 262 patients. Mean age 59.5 years. 69% were male. Mean follow-up 18.4 months. 4.9% of the BKAs were performed on patients with traumatic lower extremity injuries. 86% had diabetes. 25% were on dialysis. Ambulation rate was 77% after BKA, with 78% and 61% of unilateral and bilateral amputees ambulating, respectively. Pre-amputation variables found to be positively associated with post-amputation ambulation included female gender (P .002). Pre-amputation variables that approached significance for being negatively associatedwith post-amputation ambulation included elevated pre-operative serum creatinine level (P .053). 23% (n 67) of BKA patients required at least one operative revision with most being due to falls postoperatively. Conclusions: Following below knee amputation, regardless of etiology, most patients will go on to ambulate with a prosthesis. Additionally, our review indicated that women are even more likely to ambulate following a BKA. Given these successful outcomes following BKA, we believe BKA should be considered as a viable option for patients in whom a limb salvage effort will lead to a biomechanically compromised limb.

Predictors of Duration of Unconsciousness in Patients With Coma After Cardiac Surgery

To describe clinical and brain imaging characteristics of patients who recovered and did not recover consciousness from a coma after cardiac surgery and to investigate predictors of the duration of unconsciousness in those patients who ultimately recovered consciousness. A retrospective analysis from a cohort of patients who developed coma after cardiac surgery. A single university hospital. One hundred twelve patients with postoperative stroke, encephalopathy, and/or seizures who remained in coma longer than 24 hours after cardiac surgery. None. The authors analyzed the patients' perioperative and intraoperative characteristics, laboratory values, noncontrast head computed tomography (CT) scans, and outcomes. Patients who did not recover consciousness (n = 16) were more likely to have been classified preoperatively as New York Heart Association class III/IV (p = 0.037). In patients who recovered consciousness (n = 96), only increased preoperative serum creatinine was an independent predictor of a longer duration of unconsciousness (p = 0.011). In patients who eventually recovered consciousness and had no acute findings on brain imaging, preoperative creatinine (p = 0.014), the lowest postoperative hemoglobin (p = 0.039), and surgical emergency (p = 0.045) were independent predictors of the duration of unconsciousness (p = 0.002). In patients who regained consciousness but had acute findings on brain imaging, cardiogenic shock (p = 0.012) and the insertion of an intra-aortic balloon pump before or during surgery (p = 0.025) predicted longer durations of unconsciousness (p < 0.001). In patients who ultimately recovered consciousness after being in a coma for at least 24 hours after cardiac surgery and have no abnormality on a brain CT scan, elevated preoperative serum creatinine, urgent cardiac surgery, and lower postoperative hemoglobin were correlated with an increased duration of unconsciousness.

Occult renal dysfunction: a mortality and morbidity risk factor in coronary artery bypass grafting surgery

Elevated preoperative serum creatinine is considered an independent risk factor for postoperative mortality and morbidity in patients undergoing coronary artery bypass grafting. However, the impact of occult renal dysfunction, defined as an impairment of glomerular filtration rate with normal serum creatinine, is still unknown. The aim of this study was to analyze the effects of occult renal dysfunction on early outcomes after coronary artery bypass grafting. This was a retrospective, observational, cohort study of prospectively collected data on 9159 consecutive patients with normal serum creatinine levels undergoing coronary artery bypass grafting between April 1996 and February 2009. Patients were divided into two groups based on preoperative creatinine clearance estimated with the Cockcroft-Gault equation: 5484 patients with a creatinine clearance ≥ 60 mL/min and 3675 patients with a creatinine clearance < 60 mL/min (occult renal dysfunction group). Overall in-hospital mortality was 1%. Occult renal dysfunction was associated with a doubling in the risk of operative mortality (1.4% vs 0.7%; P = .001), postoperative renal dysfunction (5.1% vs 2.5%; P < .0001), and need for dialysis (0.8% vs 0.4%; P = .014). Moreover, occult renal dysfunction increased the risk of stroke (1% vs 0.3%; P < .0001), arrhythmia (28.5% vs 21.2%; P < .0001), and hospital stay > 7 days (36.45 vs 24.5%; P < .0001). In a multivariable analysis adjusting for preoperative risk factors, occult renal dysfunction was confirmed to be an independent predictor of mortality (odds ratio, 1.72), postoperative renal dysfunction (odds ratio, 1.9), dialysis (odds ratio, 1.82), stroke (odds ratio, 2.6) arrhythmia (odds ratio, 1.42), and hospital stay > 7 days (odds ratio, 1.65). Occult renal dysfunction is an independent risk factor for early mortality and morbidity in patients undergoing coronary artery bypass grafting.

Renal Impairment Following Total Joint Arthroplasty: Who Is at Risk?

Postoperative renal impairment is a serious complication of major surgeries that leads to increased morbidity and mortality. The objective of our study was to identify the risk factors for renal impairment following total joint arthroplasty. Among 17 938 total joint arthroplasties performed between 2000 and 2007, patients developing renal complications were identified. For performing univariate and multivariate analyses, patients with renal impairment were matched in a 1:2 ratio with control group who did not develop renal impairment. Ninety-eight (0.55%) patients developed either acute renal failure or acute renal injury. We identified the following as independent risk factors: elevated body mass index; elevated preoperative serum creatinine; and history of chronic obstructive pulmonary disease, liver disease, congestive heart failure, hypertension, and underlying heart disease. Renal impairment was significantly associated with increased duration of hospital stay and with in-hospital and 1-year all-cause mortality. In high-risk patients, preoperative optimization might be considered in an attempt to reduce the incidence of such a complication.

Renal insufficiency after cardiac surgery: a challenging clinical problem

Acute renal insufficiency (ARI) after cardiac surgery is a complex and frequent clinical problem. It increases short- and long-term mortality, the incidence of post-operative complications such as respiratory infections, sepsis, and gastrointestinal bleeding, and intensive care unit (ICU) and hospital lengths of stay.1,2 Identified risk factors for post-operative ARI in cardiac surgical patients include pre-operative renal insufficiency, advanced age, history of congestive heart failure, diabetes mellitus, recent exposure to nephrotoxic agents such as contrast dye, intra-aortic balloon pump, emergency operation, prolonged cardiopulmonary bypass (CPB) time, low urinary output during CPB, and need for deep hypothermic circulatory arrest ( Figure 1 ).2,3 Figure 1 Risk factors for acute renal insufficiency after cardiac surgery. Analysing the pre-operative risk factor trends in cardiac surgery during the 1990–1999 decade in the large, voluntary, nationwide STS database, Ferguson et al. 4 showed that the incidence of pre-operative renal insufficiency increased from 3.0 to 4.6%. Recently, Swaminathan et al. 5 showed that, among coronary artery bypass grafting (CABG) patients, the incidence of acute renal failure increased significantly from 1.1 to 4.1%. While the proportion of a diagnosis of acute renal failure cases requiring haemodialysis decreased from 15.8 to 8.7%, the percentage of survivors with post-operative special care requirements increased from 35.5 to 64.5%.5 Over the last few years, the prognostic importance of mildly elevated pre-operative serum creatinine levels or small increases in post-operative creatinine values became apparent, leading to a shift in our understanding of the importance of even small degrees of acute kidney injury. Antunes et al. 6 reported, among 2122 patients with pre-operative creatinine serum levels <2.0 mg/dL having CABG and an … *Corresponding author. Tel: +32 4 366 7163, Fax: +32 4 221 31 58, Email: philippe.kolh{at}chu.ulg.ac.be

The Outcome of Endovascular Repair of Small Abdominal Aortic Aneurysms

To assess the outcome of endovascular repair (EVAR) of small abdominal aortic aneurysms (AAA, <or=5.5 mm maximum diameter) in Australia. Randomized trials have suggested that small AAAs should not be treated by open surgery. EVAR is associated with less perioperative mortality than open surgery for large AAAs. We assessed the outcome of EVAR of small AAAs as part of a national audit. ASERNIP-S carried out a prospective audit of EVAR performed between November 1999 and May 2001 in Australia. A total of 478 of the 961 patients entered underwent treatment of a small AAA. Data were collected regarding preoperative characteristics, procedural outcome, and intermediate success. Median follow-up was 3.2 years. Data were analyzed using Kaplan-Meier and Cox proportional hazard analyses. The 30-day mortality and technical success rates were 1.1% and 98%, respectively. Postoperative complications occurred in 29%. Survival was 84% and 52% at 3 and 5 years, respectively. Primary, assisted primary, and secondary clinical success rates were 72%, 79%, and 82%, respectively, at 3 years. Reintervention rate was 11% at 3 years; however, 15% of patients continued to have significant aortic sac enlargement. Survival was reduced in patients considered unfit for general anesthesia (odds ratio = 2.6; 95% confidence interval, 1.4-4.8, P = 0.002) or those who had elevated preoperative serum creatinine (odds ratio = 2.0; 95% confidence interval, 1.3-3.0, P = 0.001). EVAR can be carried with good perioperative outcome in patients with small AAA; however, intermediate success is hampered by the need for reintervention and continued aortic sac enlargement. At present, widespread treatment of small AAAs by EVAR would appear inappropriate.

Percutaneous endopyelotomy for secondary ureteropelvic junction obstruction: Prognostic factors affecting late recurrence

To determine prognostic variables which influence late recurrence after initially successful percutaneous endopyelotomy for secondary ureteropelvic junction obstruction (UPJO). Between July 1987 and March 2002, 67 patients with secondary UPJO were treated with percutaneous endopyelotomy at our center. Long-term follow-up data were available for 50 patients with initially successful results (42 after a single treatment and eight after repeated endopyelotomy). Follow-up excretory urography and diuretic renal scans were performed for objective evaluation. Late recurrence was diagnosed if obstruction developed after > 1 year of follow-up. Univariate (Kaplan-Meier method) and multivariate (Cox regression model) analyses of pre-, peri- and postoperative factors were carried out for detection of significant variables affecting the late recurrence rate. The follow-up period ranged from 1.27 to 13.85 years (mean 6 +/- 4.3 years). Late recurrence of UPJO was observed in seven cases (14%): 4/42 initially successful cases (9.5%) and 3/8 cases of repeated endopyelotomy (37.5%). In univariate analysis, the significant factors were severity of stenosis at the UPJ (p = 0.04), preoperative serum creatinine (p = 0.04), repetition of endopyelotomy (p = 0.03) and development of postoperative complications (p = 0.02). In multivariate analysis, all of the above factors, with the exception of severity of stenosis at the UPJ, were independent significant factors affecting late recurrence. As late recurrence was observed in 14% of cases after percutaneous endopyelotomy, long-term follow-up is needed, especially in patients with elevated preoperative serum creatinine, those in whom postoperative complications developed and those in whom a first attempt at endopyelotomy failed.