Cardiovascular death and progression to end-stage renal disease after major surgery in elderly patients.

BACKGROUND: Reliable estimates for risk of cardiovascular-specific mortality and progression to end-stage renal disease (ESRD) among elderly patients undergoing major surgery are not available. This study aimed to develop simple risk scores to predict these events. METHODS: In a single-centre cohort of elderly patients undergoing major surgery requiring hospital stay longer than 24 h, progression to ESRD and long-term cardiovascular-specific mortality were modelled using multivariable subdistribution hazard models, adjusting for co-morbidity, frailty and type of surgery. RESULTS: Before surgery, 2·9 and 11·9 per cent of 16 655 patients had ESRD and chronic kidney disease (CKD) respectively. During the hospital stay, 46·9 per cent of patients developed acute kidney injury (AKI). Patients with kidney disease had a significantly higher risk of cardiovascular-specific (CV) mortality compared with patients without kidney disease (adjusted hazard ratio (HR) for CKD without AKI 1·60, 95 per cent c.i. 1·25 to 2·01; AKI without CKD 1·70, 1·52 to 1·87; AKI with CKD 2·80, 2·50 to 3·20; ESRD 5·21, 4·32 to 6·27), as well as increased progression to ESRD (AKI without CKD 5·40, 3·44 to 8·35; CKD without AKI 8·80, 4·60 to 17·00; AKI with CKD 31·60, 19·90 to 49·90). CV Death and ESRD Risk scores were developed to predict CV mortality and progression to ESRD. Calculated CV Death and ESRD Risk scores performed well with c-statistics: 0·77 (95 per cent c.i. 0·76 to 0·78) and 0·82 (0·78 to 0·86) respectively at 1 year. CONCLUSION: Kidney disease in elderly patients undergoing major surgery is associated with a high risk of CV mortality and progression to ESRD. Risk scores can augment the shared decision-making process of informed consent and identify patients requiring postoperative renal-protective strategies.

ANTECEDENTES: No se dispone de estimaciones fiables acerca del riesgo de mortalidad cardiovascular y de progresión a insuficiencia renal terminal (end-stage renal disease, ESRD) en pacientes longevos a los que se realiza cirugía mayor. Este estudio tiene como objetivo desarrollar un sistema de puntuación simple de riesgos para predecir estos eventos. MÉTODOS: En una cohorte de un solo centro de 16.655 pacientes longevos a los que se realizó cirugía mayor con hospitalización de más de 24 horas, se estimó la progresión a ESRD y la mortalidad cardiovascular a largo plazo utilizando modelos multivariables de subdistribucion de riesgos ajustados por comorbilidades, fragilidad y tipo de cirugía. RESULTADOS: Antes de la cirugía, presentaron ESRD y enfermedad renal crónica (chronic kidney Disease, CKD) un 2,9% y un 12,3% de los pacientes, respectivamente. Durante la hospitalización, el 46,9% de los pacientes desarrollaron insuficiencia renal aguda (acute kidney injury, AKI). Los pacientes con enfermedad renal tenían un riesgo significativamente mayor de mortalidad cardiovascular (CV) en comparación con los pacientes sin enfermedad renal para presentar AKI (cociente de riesgos instantáneos, hazard ratio, HR ajustado) 1,6 (i.c. del 95% 1,3-2,0), AKI sin CKD 1,7 (1,5-1,9), AKI en presencia de CKD 2,8 (2,5-3,2) y ESRD 5,2 (4,3-6,3), así como una mayor progresión a ESRD (AKI sin CKD 5,4 (3,4-8,4), CKD sin AKI 8,8 (4,6-17), y AKI en presencia de CKD 31,6 (19,9-49,9)). Se desarrollaron las escalas CV Death y ESRD Risk para predecir la mortalidad cardiovascular y la progresión a ESRD. Ambas escalas funcionaron bien a 1 año con un coeficiente de concordancia de 0,77 (i.c. del 95% 0,76-0,78) y 0,82 (0,78-0,86) respectivamente. CONCLUSIÓN: La enfermedad renal en pacientes longevos tras cirugía mayor se asocia con un elevado riesgo de mortalidad cardiovascular y de progresión a ESRD. Las escalas de riesgo pueden facilitar la toma de decisiones en el momento del consentimiento informado e identificar los pacientes que requieren estrategias de protección renal postoperatorias.

Acute kidney injury in major gynaecological surgery: an observational study.

OBJECTIVE: To assess the prevalence, outcomes and cost associated with acute kidney injury (AKI) defined by consensus risk, injury, failure, loss, and end-stage kidney (RIFLE) criteria after gynaecologic surgery. DESIGN: Retrospective single-centre cohort study. SETTING: Academic medical centre. SAMPLE: Two thousand three hundred and forty-one adult women undergoing major inpatient gynaecologic surgery between January 2000 and November 2010. METHODS: AKI was defined by RIFLE criteria as an increase in serum creatinine greater than or equal to 50% from the reference creatinine. We used multivariable regression analyses to determine the association between perioperative factors, AKI, mortality and cost. MAIN OUTCOME MEASURES: AKI, combined major adverse events (hospital mortality, sepsis or mechanical ventilation), 90-day mortality and hospital cost. RESULTS: Overall prevalence of AKI was 13%. The prevalence of AKI was associated with the primary diagnosis. Of women with benign tumour surgeries, 5% (43/801) experienced AKI compared with 18% (211/1159) of women with malignant disease (P < 0.001). Only 1.3% of the whole cohort had evidence of urologic mechanical injury. In a multivariable logistic regression analysis, AKI patients had nine times the odds of a major adverse event compared to patients without AKI (adjusted odds ratio 8.95, 95% confidence interval 5.27-15.22). We have identified several readily available perioperative factors that can be used to identify patients at high risk for AKI after in-hospital gynaecologic surgery. CONCLUSIONS: AKI is a common complication after major inpatient gynaecologic surgery associated with an increase in resource utilisation and hospital cost, morbidity and mortality.

QT dispersion in hemodialysis and CAPD patients.

Prolongation of repolarization dispersion (QT interval dispersion) measured from the 12-lead surface ECG has been associated with sudden cardiac death and ventricular tachyarrhythmias in a variety of cardiac disorders. The aim of our study was to assess the effects of hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD) on QT dispersion in end-stage renal disease patients. 20 chronic HD patients (mean age 57.75 +/- 13.79 years) and 20 CAPD patients (mean age 50.79 +/- 14.94 years) who had no complaints and symptoms of cardiac arrhythmias as well as 20 healthy volunteers (mean age 48.74 +/- 10.88 years) underwent ECG testing. All HD patients were on bicarbonate three times weekly with cuprophane capillaries. 12-lead ECGs were recorded on the day after HD. The CAPD patients were on a standard CAPD program (four times daily with 2,000 cm(3) peritoneal fluid). ECGs were recorded when the patients were receiving their regular standard CAPD program. All ECGs were analyzed manually by one observer. There were no statistically significant differences in dialysis duration, blood urea nitrogen, creatinine, sodium, calcium, and parathormone values between the HD and CAPD patients. The serum potassium values were significantly higher in HD patients when compared to CAPD patients. There was no difference in the mean of maximal QT among all three groups. The rate of QT interval dispersions was significantly higher in HD and CAPD patients as compared with healthy controls (p < 0.05). There was no statistically significant difference in the QT dispersion rates between HD and CAPD patients. In conclusion, there is a tendency to cardiac arrhythmias in HD patients during the postdialysis period. Although CAPD patients are receiving dialysis daily, they also have higher rates of QT dispersions and accordingly a tendency to arrhythmias.

Technical survival of CAPD catheters: comparison between percutaneous and conventional surgical placement techniques.

BACKGROUND: Percutaneous peritoneal dialysis catheter (PDC) placement is a well-tolerated, rapidly performed bedside procedure that allows a rapid initiation of CAPD. We compared the technical survival of PDCs while comparing the mode of insertion. METHODS: We retrospectively reviewed 215 PDCs inserted over a 60-month period in 191 patients on CAPD therapy. Of these, 133 were placed percutaneously by nephrology staff (group P) and 82 were placed using conventional surgical techniques by surgical staff (group S). The total experience accumulated was 4000 patient-months: 2260 patient-months in group P and 1740 patient-months in group S. RESULTS: The incidence of complications in PDCs did not differ between the groups (1 episode/33 patient-months in group P and 1 episode/29 patient-months in group S). Two episodes of early leakage and 9 episodes of late leakage were observed in group P compared with one early leakage and 4 episodes of late leakage in group S. Of the mechanical complications in group P, 8.86% were due to catheter malfunction, including catheter tip migration and obstruction, compared with 12.63% in group S. The incidence of catheter infections was 1 episode/73 patient-months in group P and 1 episode/62 patient-months in group S. Significantly more catheters were removed in group S compared with group P (40% vs 16%, P<0.001). One-year and 2-year technical survivals were 90% and 82% in group P, and 73% and 60% in group S (P=0.0032), respectively. CONCLUSIONS: Percutaneous bedside placement of PDCs by nephrologists provides a safe and reliable access for peritoneal dialysis.

The impact of the earthquake in northwestern Turkey on the continuous ambulatory peritoneal dialysis patients who were living in the earthquake zone.

In August 1999, an earthquake of magnitude 7.8 on the Richter scale hit northwestern Turkey. The epicenter was in Izmit, an industrial town about 60 km from Istanbul. This paper presents data about the fate of CAPD patients who were living in that region at the time of the earthquake. A total of 42 continuous ambulatory peritoneal dialysis (CAPD) patients (14 females, 28 males; 37 adult patients, 5 pediatric patients) were permanent residents of the earthquake region. They were followed in the CAPD units of Marmara University Hospital (n = 6), Gata Military Hospital (n = 2), and Goztepe SSK Hospital (n = 10, including the 5 pediatric patients) in Istanbul, and in Uludag University Hospital in Bursa (n = 6) and Kocaeli University Hospital in Izmit (n = 18). Two CAPD patients, together with their families, died under the rubble in the city of Golcuk. One CAPD nurse from Kocaeli University Hospital in Izmit also died a victim of the earthquake. One patient who lived in Golcuk was under the rubble for 3 hours; she was rescued with no crush injuries and was able to continue with CAPD 24 hours after her rescue. Eight patients reported that their homes were completely destroyed during the earthquake, while nine patients reported serious damage to their houses. Ten patients had to move to other towns to live with relatives because their homes were no longer suitable for habitation, and twelve patients had to stay permanently in tents provided by the Red Cross. All of the patients were able to continue their CAPD therapy and had no interruption in the supply of their CAPD solutions. Four patients on continuous cycling peritoneal dialysis (CCPD) therapy continued to use their HomeChoice machines (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.) even while living in a tent. CAPD patients from the Kocaeli University Hospital had to be temporarily referred to other CAPD centers in Istanbul and Bursa because the Kocaeli University Hospital was seriously damaged in the earthquake. We expect that these major changes in quality of life circumstances will have an important impact on the morbidity of these patients, especially in regard to the rate of peritonitis and the adequacy of dialysis.

Severe hyperkalemia in two renal transplant recipients treated with standard dose of trimethoprim-sulfamethoxazole.

Hyperkalemia is a serious electrolyte disorder and is a frequent finding in renal transplant recipients. Trimethoprim-induced hyperkalemia has been increasingly reported in recent years. We describe two renal transplant recipients who developed end-stage renal disease secondary to familial Mediterranean fever and presented with severe hyperkalemia secondary to the use of standard dose of trimethoprim. One of the patients had potential underlying adrenal insufficiency, which might be a contributing factor for the development of hyperkalemia. We concluded that renal transplant patients receiving even the standard dose of trimethoprim should be monitored closely for the development of hyperkalemia. They should be recognized as a group with increased risk in regard to their concurrent renal insufficiency, concomitant use of cyclosporine, and associated tubulointerstitial disease. Patients with secondary amyloidosis are at even greater risk, and subclinical adrenal insufficiency may be an underlying risk factor for the development of severe, life-threatening hyperkalemia among this group of patients.

Association between salt sensitivity and target organ damage in essential hypertension.

Cardiovascular events occur more frequently in sodium-sensitive patients with essential hypertension; recently, sodium sensitivity was shown to be a cardiovascular risk factor independently of other classic factors such as blood pressure and cigarette smoking This study examined the relationship between salt sensitivity status and target organ damage in hypertensive patients. Ninety-six patients (35 men, 61 women) with moderate essential hypertension were studied for salt sensitivity status and the presence of target organ damage, including hypertensive retinopathy, serum creatinine, creatinine clearance, and urinary albumin excretion (UAE). Four different patterns of left ventricular anatomic adaptation were identified by categorizing patients according to the values of left ventricular mass index and relative wall thickness by the means of echocardiography. Forty-five (47%) patients were shown to be salt-sensitive, in contrast to 51 (53%) salt-resistant subjects. Serum creatinine and UAE were significantly higher in the group of salt-sensitive hypertensives (P < .05 and P < .001, respectively). Left ventricular mass index (LVMI), relative wall thickness (RWT), and left atrial index (LAI) were all significantly higher in the group of salt-sensitive hypertensive patients. Concentric hypertrophy was significantly more prevalent in the salt-sensitive group (37.8% v 11.8%; P < .01). The prevalence of hypertensive retinopathy in the salt-sensitive group was 84.4%, in contrast to 59.6% in the salt-resistant group (P < .01). Multivariate regression analysis revealed salt sensitivity as a significant predictor of LVMI, RWT, and UAE, independently of age, body mass index, and mean blood pressure. In conclusion, salt-sensitive hypertensive patients are more prone to develop severe hypertensive target organ damage that may enhance their risk of renal and cardiovascular morbidity.

Tetracycline-induced acute interstitial nephritis as a cause of acute renal failure.

Acute interstitial nephritis with severe acute renal failure is reported following tetracycline treatment in a 22-year-old male medical student. Acute renal failure developed within 48 h of a single repeated tetracycline dose and presented 2 days after taking the drug when there was oliguria, nausea, vomiting and bilateral loin pain without rash and fever. The serum creatinine concentration was 8.6 mg/dl and blood urea nitrogen 84 mg/dl. Examination of the urinary sediment revealed 15-20 RBCs per high-power field, and occasional granular and hyaline casts. Percutaneous renal biopsy performed immediately after admission revealed acute interstitial nephritis with immune complexes along the tubular basement membrane and intact glomeruli and was consistent with type 2 interstitial nephritis. Within 4 days of commencement of steroid treatment and hemodialysis, the urine output started to increase with improvement in serum creatinine and BUN levels and after 2 weeks of therapy hemodialysis was discontinued. He remains well 1 year following his illness with complete normalization of his renal function. Although a number of renal side effects of tetracycline antibiotics have been reported, acute interstitial nephritis is rarely caused by tetracycline treatment having been reported just twice following systemic use of minocycline.