Nephrologist Expert Witness

Nephrology is a field of internal medicine; it emphasizes the study of the kidney. Nephrologists diagnose and treat kidney diseases. They use a variety of techniques to do so, including dialysis and renal transplants.

One of AME’s nephrology expert witnesses has written two exclusive medical malpractice articles that we have provided, for your interest, below. Mild Hyponatremia: new risk of memory changes, gait disturbances and death

Hyponatremia: Hyponatremia is defined as a lower than normal serum sodium concentration using routine laboratory testing of serum electrolytes. Although chronic hyponatremia below 120 mEq almost universally prompts medical investigation, milder forms are usually overlooked or disregarded as being of little clinical significance. Recently, mild-moderate hyponatremia (i.e., a serum sodium concentration >125-135 mEq/L) has been associated with distinct symptoms as well as with increased mortality after hospitalization.

What causes hyponatremia? Many conditions are associated with chronic hyponatremia, the single most common electrolyte abnormality. These include inflammation in the brain or lung, cancers, thyroid disease, kidney disease, heart failure, and several categories of medications such as oral hypoglycemics (used in patents with diabetes mellitus), narcotics, diuretics, and antidepressants, particularly those agents referred to as selective serotonin receptor inhibitors (SSRI agents).

What are the consequences of mild hyponatremia? Recent epidemiologic evidence associates mild hyponatremia (average 131 mEq/L) with impairment of short-term memory as well as an abnormal gait. While both deficits are concerning, the risk of fall is significant (more than double compared to patients with a normal serum sodium), especially in the elder population at greatest risk for hip and femoral fractures.

Standard of Care: Serum sodium should be evaluated in all patients receiving routine laboratory testing for serum electrolytes, glucose and kidney function. The finding of a serum sodium concentration below 135 mEq/L should prompt inquiry for associated changes in short-term memory, as well as an evaluation of gait. If either are implied, a search for the cause of hyponatremia is important in normalizing these parameters, thereby potentially reducing the risk of short-term memory loss, the likelihood of falling due to an unsteady gait, and decreasing the risk of mortality, particularly in patients with underlying chronic disease conditions.

References: (1-3)

  1. Hufschmidt A, Shabarin V, Zimmer T. Drug-induced confusional states: the usual suspects? Acta Neurol Scand. 2009;120(6):436-8.
  2. Sandhu HS, Gilles E, DeVita MV, Panagopoulos G, Michelis MF. Hyponatremia associated with large-bone fracture in elderly patients. Int Urol Nephrol. 2009;41(3):733-7.
  3. Waikar SS, Mount DB, Curhan GC. Mortality after hospitalization with mild, moderate, and severe hyponatremia. Am J Med. 2009;122(9):857-65.

About this Expert:

The Nephrologist Expert who wrote this article is an Associate Professor of Medicine and an attending physician in the Renal Section. His interests include education of medical students and house staff, basic research on the cellular mechanisms of ischemic acute renal failure and the care of patients with both general medical and renal diseases. This Expert is the senior author of numerous publications in the area of the cellular stress response to acute renal ischemia and has been a Principal Investigator for the National Institutes of Health for almost 20 years. He also received several awards for excellence in teaching from medical students, house staff and colleagues. Most recently, he was a finalist for the Metcalf Teaching Award for full-time faculty and received the Grant V. Rodkey award from the Medical Society for significant contributions to medical student education and mentoring. This expert has been involved in the care of complex internal medicine and nephrology patients for more than 25 years in both private practice and university hospital settings.

Dialysis Unit Communication – Real Time or Real Problem

Dialysis Unit Communication: At present there are more than 6500 dialysis centers in the Untied States that provide life saving care for patients with end stage renal disease (ESRD) requiring in renal replacement therapy. This often thrice-weekly form of treatment has become commonplace in virtually every major city and suburb in the US. Dialysis care is almost universally provided by Nephrologists (physicians specializing in the diagnosis and treatment of kidney diseases) in close collaboration with a team of health care providers that includes specially trained dialysis nurses technicians, social workers and dieticians. Dialysis care is now considered sufficiently routine that the Nephrologists need not be present during each treatment.

Potential Consequences of Dialysis:

Potential Consequences of Dialysis: As with any procedure, hemodialysis carrels a small but significant risk of complication including infection, low blood pressure, and bleeding. The risk of choric blood loss is real, even under ideal conditions; however, blood los may also be acute, especially in patients with plastic dialysis catheters that are susceptible to accidental disconnection during or after the dialysis procedure.

Standard of Care: Recent evidence suggests that hemodialysis units widely vary in standardizing communication when untoward vents occur in the absence of the Nephrologist. While some units report any unit ward event, others elect not to inform the Nephrologist, potentially causing these events to be unaddressed, thereby increasing the risk of recurrence, complications and even death. Partly as a result to this variability in practice, it is necessary for physician to review the “event threshold” that mandates communication between the Dialysis Unit and Nephrologist in order to prevent or minimize or the risk of dialysis related complications that jeopardize the patients’ well being. It is also clear that the absence of documentation that communication has in fact occurred increases liability in cases of these unfortunate complications.

References: (4-6)

  1. Di Benedetto A, Pelliccia F, Moretti M, d’Orsi W, Starace F, Scatizzi L, et al. What causes an improved safety climate among the staff of a dialysis unit? Report of an evaluation in a large network. J Nephrol.
  2. Spiegel B, Bolus R, Desai AA, Zagar P, Parker T, Moran J, et al. Dialysis practices that distinguish facilities with below- versus above-expected mortality. Clin J Am Soc Nephrol.5(11):2024-33.
  3. Harwood L, Ridley J, Lawrence-Murphy JA, White S, Spence-Laschinger HK, Bevan J, et al. Nurses’ perceptions of the impact of a renal nursing professional practice model on nursing outcomes, characteristics of practice environments and empowerment–Part II. CANNT J. 2007;17(2):35-43.

About this Expert:

The Nephrologist Expert who wrote this article is an Associate Professor of Medicine at Boston University and an attending physician in the Renal Section at Boston Medical Center. His interests include education of medical students and house staff, basic research on the cellular mechanisms of ischemic acute renal failure and the care of patients with both general medical and renal diseases. This Expert is the senior author of numerous publications in the area of the cellular stress response to acute renal ischemia and has been a Principal Investigator for the National Institutes of Health for almost 20 years. He also received several awards for excellence in teaching from medical students, house staff and colleagues at Boston Medical Center. Most recently, he was a finalist for the Metcalf Teaching Award at Boston University for full-time faculty and received the Grant V. Rodkey award from the Massachusetts Medical Society for significant contributions to medical student education and mentoring. This expert has been involved in the care of complex internal medicine and nephrology patients for more than 25 years in both private practice and university hospital settings.