Flow measurements: Can several “Wrongs” make a “Right”?

AIMS: Although measurement of maximum flow rate (Qmax) is a standard and straightforward test, it is often difficult to obtain reliable readings. We obtained multiple measurements using a simple home uroflow device which categorizes Qmax into ranges. We hypothesize that the average of a series of relatively coarse measurements of Qmax would be more repeatable and therefore more representative of an individual's voiding function than a single, albeit more precise measurement. METHODS: We studied 22 male volunteers with a wide range of Qmax. They were asked to record flow category (<10 ml/sec; 10-15 ml/sec; 15-20 ml/sec; >20 ml/sec) and voided volume twice daily for 12 days using the home flow device. In addition, a clinic-based flow recording using a spinning-disc uroflowmeter was obtained at both the start and the end of the 12-day period. RESULTS: Good agreement between mean home flow and mean clinic flow was seen with mean (SD) difference of 1.3 (5) ml/sec. The mean for consecutive halves of an individual's home flow data showed excellent agreement (-0.2 (1.3) ml/sec). The two clinic readings showed poorer agreement (2.3 (6.8) ml/sec) than the home readings, and poorer agreement even than between clinic and home flows. CONCLUSIONS: Although simple in design, the home flowmeter actually shows greater accuracy than might be expected when used repeatedly to study the flow rates of men. Simple flow devices such as this could be used in conjunction with voiding diaries to give a more representative picture of patients' day-to-day voiding function.     

Rotary Blood Pumps for Cardiac Assistance: A “Must”?

Ventricular Assist Devices (VADs) were developed following the observation that most end-stage heart failure patients only required left heart support for survival. The trend toward left VAD implantation instead of a TAH has actually contributed to the development of nonpulsatile rotational devices. This article intends to evaluate the current and future technology of continuous flow pumps. Various issues pertaining to the long-term effects of continuous blood flow, biocompatibility of axial flow pumps, and the safety and reliability of such devices need to be addressed. Some of the advantages of rotary blood pumps include their small size, ease of implantation, and encouraging low infection rates. Certain issues such as automatic flow control, device components durability, and hemocompatibility remain unresolved. The quest for an ideal device combining optimal efficiency, ease of anatomical fit, and perfect bioacceptance, continues. Rotary blood pumps are not yet a "must."     

Use of SARS‐CoV‐2‐infected deceased organ donors: Should we always “just say no?”

In the context of a rapidly evolving pandemic, multiple organizations have released guidelines stating that all organs from potential deceased donors with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection should be deferred, including from otherwise medically eligible donors found to have mild or asymptomatic SARS‐CoV‐2 discovered on routine donor screening. In this article, we critically examine the available data on the risk of transmission of SARS‐CoV‐2 through organ transplantation. The isolation of SARS‐CoV‐2 from nonlung clinical specimens, the detection of SARS‐CoV‐2 in autopsy specimens, previous experience with the related coronaviruses SARS‐CoV and MERS‐CoV, and the vast experience with other common RNA respiratory viruses are all addressed. Taken together, these data provide little evidence to suggest the presence of intact transmissible SARS‐CoV in organs that can potentially be transplanted, specifically liver and heart. Other considerations including ethical, financial, societal, and logistical concerns are also addressed. We conclude that, for selected patients with high waitlist mortality, transplant programs should consider accepting heart or liver transplants from deceased donors with SARS‐CoV‐2 infection.     

“Turn downs” in aortic emergencies: Reassurance or uncertainty?

“Turn‐down” rate has been reported to have a significant influence on outcomes, and being turned down for an operation is associated with significant short‐term mortality risk. A study examining the impact of the pandemic on the “turn‐down” rates of acute aortic syndromes in the United Kingdom reported an overall “turn‐down” rate of  7.3% in the early part of the pandemic. This review examines the significance of “turn‐downs” in this setting and scrutinizes the adequacy of reporting this complex variable.     

Intensive Hemodialysis: Normalizing the “Unphysiology” of Conventional Hemodialysis?

Interest in intensified hemodialysis (HD) regimens is increasing internationally, as there is growing evidence that they are associated with improved outcomes. Appreciation that conventional hemodialysis (CHD), delivered as 4-hour sessions three times a week, is not providing optimal physiological replacement of renal function has led to the development of intensified dialysis therapies. These include long intermittent hemodialysis typically lasting 6-8 hours and delivered three times a week, short daily hemodialysis, providing more frequent sessions 4-7 days a week lasting 2-3.5 hours, and nocturnal hemodialysis, performed 5-7 days a week for 6-8 hours. Studies evaluating outcomes from these programs have indicated superior results to those achieved with CHD, including favorable modifications of cardiovascular risk factors and improvements in a variety of clinical measures. The objective of this review is to present available evidence supporting the hypothesis that in an attempt to provide a "more normal physiology," intensified HD regimens achieve outcomes superior to those historically achieved with CHD.     

Ethical Issues in DialysisAlan Spital,Series Editor: Do Not Resuscitate Orders and Iatrogenic Arrest During Dialysis: Should “No” Mean “No”?

An iatrogenic arrest is a cardiopulmonary arrest induced by a therapeutic effort. Frequently cardiopulmonary arrests during hemodialysis (HD) are iatrogenic. In this article I consider the question of what to do when a cardiopulmonary arrest occurs during HD in a patient with a do not resuscitate (DNR) order. I consider and reject four arguments to override the DNR order: the principle of nonmaleficence, the efficacy of resuscitation, proximate cause, and physician error. Instead, I argue that respect for patient autonomy and patient goals means that DNR orders must be respected unless there is compelling evidence that overriding the DNR would be consistent with the patient's goals. If such evidence is lacking, the physician has no moral choice but to follow the DNR order literally. As such, nephrologists need better communication with their patients regarding advance care planning and better documentation of their communication once it has occurred.