Safety outcomes of apixaban in patients with nonvalvular atrial fibrillation and severe renal impairment.

Apixaban is prescribed for stroke prevention in nonvalvular atrial fibrillation (NVAF) in patients with varying degrees of renal dysfunction. While pharmacokinetic data support apixaban in severe renal impairment, clinical safety outcomes data are limited. This retrospective cohort analysis was conducted to evaluate the safety of apixaban in patients with NVAF and renal impairment. A total of 340 patients with NVAF receiving apixaban 5 mg or 2.5 mg twice daily were included for analysis; 287 preserved renal function (pRF: CrCl ≥ 25 ml/min and SCr ≤ 2.5 mg/dl) and 53 impaired renal function (iRF: CrCl < 25 ml/min and/or SCr > 2.5 mg/dl). The primary endpoint was major bleeding in patients taking apixaban 5 mg. Secondary endpoints included major bleeding with apixaban 2.5 mg and minor bleeding in both groups. There was no difference in major bleeding events in the 5 mg pRF group (4.41%) versus iRF group (3.57%) (P = 0.66). Similar rates occurred between the 2.5 mg pRF and iRF groups. Minor bleeding events were similar regardless of renal function. The incidence of bleeding in the 5 mg group was 11.45% with pRF versus 10.71% with iRF (P = 0.6). In the 2.5 mg group, bleeding incidence was 10% with pRF versus 16% with iRF (P = 0.47). There were no observed differences in bleeding between groups with pRF or iRF, regardless of apixaban dose. Because patients with severe renal impairment were excluded from original trials, this study contributes clinical safety outcomes to the limited data for use of apixaban in this patient population.

"Awakenings": electrocardiographic findings in central sleep apnea.

Central sleep apnea is an important but frequently missed clinical diagnosis. The purpose of this clinical case series is to demonstrate that in a subset of patients with central sleep apnea, inpatient telemetry ECG recordings may reveal a consistent relationship between changes in sinus rate, AV conduction, and the presence and rate of respiratory artifact that should raise the clinical suspicion of central sleep apnea. In the three presented cases, marked sinus bradycardia or AV block was followed by the simultaneous occurrence of abrupt acceleration of heart rate and the appearance of rapid micro-oscillations consistent with respiratory artifact. These changes suggested central sleep apnea characterized by bradycardia during the apneic spells followed by awakening of the breathing center and postvagal tachycardia. In each case, central sleep apnea was confirmed by visual observation of the patient, documentation of arterial desaturations during episodes of bradycardia, and in two, by a subsequent sleep study. Physicians should be aware of the potential and significance of these electrocardiographic disturbances in patients with central sleep apnea.

Vancomycin-Associated Acute Kidney Injury with a Steep Rise in Serum Creatinine.

BACKGROUND: Vancomycin-associated (VA) acute kidney injury (AKI) is being increasingly recognized. A distinct pattern of rapid rise in serum creatinine (sCr) during VA-AKI has occasionally been observed. However, such scenarios remain underreported. METHODS: We conducted an online survey at the American Society of Nephrology Communities forum and reviewed publications of VA-AKI via PubMed or Google searching for cases of precipitous AKI (those with rise in sCr ≥1.5 mg/dL/day) attributable to vancomycin. RESULTS: We identified 12 original cases compiled from 6 different hospitals and 4 published cases (n = 16; 38% women, age 43.5 ± 16 years, weight 108 ± 23 kg, body mass index 35 ± 7 kg/m2) of precipitous AKI observed shortly after large cumulative doses of VA (8.8 ± 5 g). The median steepest 24-h rise in sCr was 2.6 mg/dL (range 1.5-3.5 mg/dL) and the slope of the initial 48-h sCr rise was greater than that of a control AKI (non-VA, n = 48) group (2.03 ± 0.1 vs. 0.62 ± 0.0 mg/dL/day; p < 0.0001). The steep rise in sCr in the VA-AKI was not accompanied by anuria. Overt rhabdomyolysis was absent in all cases. Further, in 3 precipitous VA-AKI cases, simultaneous serum cystatin C values did not rise precipitously, suggesting that the reductions in glomerular filtration rate were overestimated by the sCr increase. CONCLUSIONS: VA-AKI can manifest with a precipitous rise in sCr shortly after a high cumulative dose of vancomycin. True toxic tubular injury overrepresented by the sCr rise is postulated.

A 40-day water-only fast by a Pentecostal woman: clinical and religious observations.

A 57-year-old woman presented to the hospital after a 40-day acaloric (water-only) fast, which was motivated by her Christian beliefs and Pentecostal affiliation. She exhibited hyponatremia on admission, and developed hypokalemia, hypophosphatemia and hypomagnesemia during refeeding. The authors are unaware of other published case reports describing medical and religious aspects of prolonged fasting by Christians for spiritual reasons. Nevertheless, this practice is advocated by some Pentecostal and non-Pentecostal sources, and may be more common than is widely recognized.