Treatment Effect of Percutaneous Coronary Intervention in Dialysis Patients With ST-Elevation Myocardial Infarction.

RATIONALE & OBJECTIVE: Patients receiving maintenance dialysis have higher mortality after primary percutaneous coronary intervention (pPCI) than patients not receiving dialysis. Whether pPCI confers a benefit to patients receiving dialysis that is similar to that which occurs in lower-risk groups remains unknown. We compared the effect of pPCI on in-hospital outcomes among patients hospitalized for ST-elevation myocardial infarction (STEMI) and receiving maintenance dialysis with the effect among patients hospitalized for STEMI but not receiving dialysis. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: We used the National Inpatient Sample (2016-2018) and included all adult hospitalizations with a primary diagnosis of STEMI. PREDICTORS: Primary exposure was PCI. Confounders included dialysis status, demographics, insurance, household income, comorbidities, and the elective nature of the admission. OUTCOME: In-hospital mortality, stroke, acute kidney injury, new dialysis requirement, vascular complications, gastrointestinal bleeding, blood transfusion, mechanical ventilation, palliative care, and discharge destination. ANALYTICAL APPROACH: The average treatment effect (ATE) of pPCI was estimated using propensity score matching independently within the group receiving dialysis and the group not receiving dialysis to explore whether the effect is modified by dialysis status. Additionally, the average marginal effect (AME) was calculated accounting for the clustering within hospitals. RESULTS: Among hospitalizations, 4,220 (1.07%) out of 413,500 were for patients receiving dialysis. The dialysis cohort was older (65.2 ± 12.2 vs 63.4 ± 13.1, P < 0.001), had a higher proportion of women (42.4% vs 30.6%, P < 0.001) and more comorbidities, and had a lower proportion of White patients (41.1% vs 71.7%, P < 0.001). Patients receiving dialysis were less likely to undergo angiography (73.1% vs 85.4%, P < 0.001) or pPCI (57.5% vs 79.8%, P < 0.001). Primary PCI was associated with lower mortality in patients receiving dialysis (15.7% vs 27.1%, P < 0.001) as well as in those who were not (5.0% vs 17.4%, P < 0.001). The ATE on mortality did not differ significantly (P interaction = 0.9) between patients receiving dialysis (-8.6% [95% CI, -15.6% to -1.6%], P = 0.02) and those who were not (-8.2% [95% CI, -8.8% to -7.5%], P < 0.001). The AME method showed similar results among patients receiving dialysis (-9.4% [95% CI, -14.8% to -4.0%], P < 0.001) and those who were not (-7.9% [95% CI, -8.5% to -7.4%], P < 0.001) (P interaction = 0.6). Both the ATE and AME were comparable for other in-hospital outcomes in both groups. LIMITATIONS: Administrative data, lack of pharmacotherapy and long-term outcome data, and residual confounding. CONCLUSIONS: Compared with conservative management, pPCI for STEMI was associated with comparable reductions in short-term mortality among patients irrespective of their receipt of maintenance dialysis.

Initiation of maintenance hemodialysis through central venous catheters: study of patients' perceptions based on a structured questionnaire.

BACKGROUND: Despite well-publicized suggestions to utilize arteriovenous fistulae and grafts to initiate hemodialysis, too many patients in the United States start dialysis via central venous catheters despite their well-known association with increased morbidity, mortality, and cost. METHODS: To determine the reasons for this high rate of catheter use, and, ultimately, ways to reduce it, we developed a questionnaire designed to determine where in the process of patient care the process to fistula or graft placement was not completed, thus requiring the use of central venous catheters. The questionnaire was reviewed by several nephrologists not involved with the study. We administered the questionnaire to 52 consecutive hospitalized patients who started maintenance dialysis with catheters at a University-affiliated Hospital and referral center. The questionnaire asked each patient to provide details pertaining to pre-dialysis care, referrals, and follow-through on recommended referrals. If the patient did not see the physician to whom he/she was referred, we asked the reason(s) for such failure. RESULTS: Patient responses showed that there were two major lapses in the transition from diagnosis of advanced kidney disease to construction of appropriate dialysis access: failure by the patients to see a nephrologist and/or an access surgeon, and failure by physicians to refer patients to an access surgeon. Twenty percent of the patients failed to follow up with either a nephrologist or a surgeon. Only 38% (15/40) of those seen by a nephrologist had been referred to a surgeon. CONCLUSIONS: The quality of care was impaired by lack of referral to surgeons by nephrologists and by lack of follow-through by patients. Areas for improvement include improved communications between physicians and patients and more careful follow-up by both physicians and patients. Several methods of providing better patient care and communication between patients and nephrologists are recommended.

Hypokalemia associated with acute colonic pseudo-obstruction in an ESRD patient.

Ogilvie's syndrome, or acute colonic pseudo-obstruction, is characterized by massive dilation of the colon without mechanical obstruction. Water and electrolytes often can be sequestered in the dilated intestinal loops resulting in profuse and watery diarrhea as well as hypokalemia. We report an anuric, end-stage renal disease (ESRD) patient undergoing peritoneal dialysis (PD) who developed acute colonic pseudo-obstruction causing a prolonged hospitalization. He also developed severe hypokalemia with a serum potassium (K+) as low as 2.4 mEq/L and required 180 - 240 mEq of potassium chloride per day for more than a month to correct it. While PD K+ losses often contribute to hypokalemia, the PD K+ loss was estimated to be only 39 mEq/day. Therefore, PD could only contribute modestly to the recalcitrant hypokalemia observed during the episode of pseudo-obstruction. It has been shown, however, that patients with colonic pseudo-obstruction have enhanced colonic K+ secretion. In addition, experimental studies in patients with chronic kidney disease (CKD) have demonstrated that colonic K+ excretion can be up to 3 times greater than in individuals with normal renal function. This increase may involve an upregulation of the large conductance K+ channel (maxi-K), also known as the BK channel, in the apical border of the colonocytes. We suggest that ESRD may have placed our patient at a greater risk of developing hypokalemia as his colon may have already adapted to secrete more K+. Clinicians should be aware of this extrarenal K+ wasting etiology in patients with colonic pseudo-obstruction, particularly in those with CKD where such a severe K+ deficit is not anticipated and, therefore, may inhibit more rigorous K+ replacement.

Temporal Trends in the Outcomes of Dialysis Patients Admitted With Acute Ischemic Stroke.

BACKGROUND: There is a paucity of contemporary data on the characteristics and outcomes of acute ischemic stroke (AIS) in patients on maintenance dialysis. METHODS AND RESULTS: We used the nationwide inpatient sample to examine contemporary trends in the incidence, management patterns, and outcomes of AIS in dialysis patients. A total of 930 010 patients were admitted with AIS between 2003 and 2014, of whom 13 642 (1.5%) were on dialysis. Overall, the incidence of AIS among dialysis patients decreased significantly (Ptrend<0.001), while it remained stable in non-dialysis patients (Ptrend=0.78). Compared with non-dialysis patients, those on dialysis were younger (67±13 years versus 71±15 years, P<0.001), and had higher prevalence of major comorbidities. Black patients constituted 35.2% of dialysis patients admitted with AIS compared with 16.7% of patients in the non-dialysis group (P<0.001). After propensity score matching, in-hospital mortality was higher in the dialysis group (7.6% versus 5.2%, P<0.001), but this mortality gap narrowed overtime (Ptrend<0.001). Hemorrhagic conversion and gastrointestinal bleeding rates were similar, but blood transfusion was more common in the dialysis group. Rates of severe disability surrogates (tracheostomy, gastrostomy, mechanical ventilation and non-home discharge) were also similar in both groups. However, dialysis patients had longer hospitalizations, and accrued a 25% higher total cost of acute care. CONCLUSIONS: Dialysis patients have 8-folds higher incidence of AIS compared withnon-dialysis patients. They also have higher risk-adjusted in-hospital mortality, sepsis and blood transfusion, longer hospitalizations, and higher cost. There is a need to identify preventative strategies to reduce the risk of AIS in the dialysis population.

Trends and Outcomes of Aortic Valve Replacement in Patients With End-Stage Renal Disease on Hemodialysis.

Hemodialysis (HD) patients with aortic stenosis are less likely to undergo aortic valve replacement (AVR) due to their excess perioperative mortality. We aimed to evaluate contemporary utilization and outcomes of combined and isolated AVR in HD patients. The Nationwide Inpatient Sample was used to identify 142,046 patients who underwent AVR in 2005 to 2014, of whom 2,264 (1.6%) were on HD. Crude and adjusted in-hospital outcomes and costs were assessed in unmatched and propensity-matched cohorts of HD and non-HD patients, respectively. The utilization of AVR in HD patients increased significantly (p = 0.047), with a significant decrease in mortality (p = 0.013). Compared with patients not on HD, crude in-hospital mortality in HD patients was twice higher (11.8% vs 6.2%, p <0.0001). HD patients had more blood transfusion and a trend toward more strokes. Lengths of stay and hospital charges, and rates of nonhome discharges were also higher in the HD group. In the propensity-matched cohorts of HD versus non-HD patients, in-hospital mortality rates after AVR remained twofold higher in the HD group (8.1% vs 3.9%, p <0.001). Rates of blood transfusion, cardiac tamponade, length of stay, hospital charges, and nonhome discharges were also higher in HD patients. In conclusion, AVR utilization in HD patients increased and its associated mortality decreased over the last decade. However, AVR mortality in HD patients remained twofold higher compared with non-HD patients. Also, AVR in HD patients was associated with higher cost, longer hospitalizations, and more frequent nonhome discharges.

Outcomes of Transcatheter and Surgical Aortic Valve Replacement in Patients on Maintenance Dialysis.

BACKGROUND: The introduction of transcatheter aortic valve replacement (TAVR) expanded definitive therapy of aortic stenosis to many high-risk patients, but it has not been fully evaluated in the dialysis population. We aimed to evaluate the current trend and in-hospital outcome of surgical aortic valve replacement (SAVR) and TAVR in the dialysis population. METHODS: Severe aortic stenosis patients on maintenance dialysis who underwent SAVR or TAVR in the Nationwide Inpatient Sample database from January 1, 2005, through December 31, 2014, were included in our comparative analysis. The trends of SAVR and TAVR were assessed. In-hospital mortality, rates of major adverse events, hospital length of stay, cost of care, and intermediate care facility utilization were compared between the 2 groups using both unadjusted and propensity-matched data. RESULTS: Utilization of aortic valve replacement in dialysis patients increased 3-fold; a total of 2531 dialysis patients who underwent either SAVR (n = 2264) or TAVR (n = 267) between 2005 and 2014 were identified. Propensity score matching yielded 197 matched pairs. After matching, a 2-fold increase in in-hospital mortality was found with SAVR compared with TAVR (13.7% vs 6.1%, P = .021). Patients who underwent TAVR had more permanent pacemaker implantation (13.2% vs 5.6%, P = .012) but less blood transfusion (43.7% vs 56.8%, P = .02). Rates of other key morbidities were similar. Hospital length of stay (19 ± 16 vs 11 ± 11 days, P <.001) and non-home discharges (44.7% vs 31.5%, P = .002) were significantly higher with SAVR. Cost of hospitalization was 25% less with TAVR. CONCLUSION: In patients on maintenance dialysis, TAVR is associated with lower hospital mortality, resource utilization, and cost in comparison with SAVR.