Page 77 - JSOM Fall 2022

Skeletal muscle destruction can be caused by vigorous exercise, of P waves, widening of the QRS complex, bradycardia, si­
seizures, crush or blast injuries, electrical injuries, heat injuries, nusoidal pattern, and ST depression. 8,34 Management involves
or limb ischemia from compartment syndrome or snake bites. cardiomyocyte membrane stabilization with calcium gluco­
Exam findings may be significant for tea colored urine and dif­ nate, intracellular shift of potassium with insulin plus dextrose
30
fuse muscle pain. and/or albuterol, and excretion of potassium with loop diuret­
ics. In severe cases or when refractory to the above treatments,
Classically, a urinalysis will be positive for blood on the dip­ renal replacement therapy (RRT) may be needed. Indications
34
stick but have no red blood cells detected on microscopy. Cre­ for RRT follow the mnemonic AEIOU: 11
atine kinase (CK) levels five times the upper limit of normal
are diagnostic for rhabdomyolysis with levels in the tens of – Acidosis (pH <7.1)
+
thousands not uncommon in severe cases. CK levels increase – Electrolyte abnormalities (K >6.5 refractory to treatment)
within 12 hours following injury and peak between 24–72 – Intoxication (salicylates, lithium, methanol, ethylene gly­
hours. 30,31 Return to baseline CK levels generally occurs within col, isopropanol)
31
5–10 days. Treatment consists of correction of electrolyte de­ – Overload of fluid (refractory to diuretics)
rangements and aggressive fluid hydration to a targeted urine – Uremia (pericarditis, altered mental status, uremic bleeding)
output of 300mL/h. 30,31 Urine alkalinization with sodium bi­
carbonate remains a controversial treatment without sufficient
research to support universal use. 30,31 Conclusion
AKI is a serious, often silent, medical condition with diverse
etiologies and complex pathophysiology. Treatment is preven­
Postrenal AKI
tion and supportive care with a focus on electrolyte repletion,
Postrenal AKI is caused by obstruction distal to the kidneys fluid correction, minimization of nephrotoxic exposures, and
causing backup of urine and filtration with subsequent de­ identification and treatment of the root cause.
creased urine output, renal venous congestion, and decreased
GFR. Causes to consider include an enlarged prostate, pelvic Disclosure
organ prolapse, urethral trauma, infection, ureteral stones, We have no conflicts to disclose.
bladder stones, spinal trauma, and obstructed Foley cathe­
32
ters. Physical exam findings suggestive of postrenal obstruc­ Disclaimer
tion include a tender, palpable bladder, a large prostate on a The viewpoints expressed in this paper reflect those solely of
digital rectal exam, pelvic organ prolapse on pelvic exam, and the authors and do not reflect the views of the US Department
blood at the urethral meatus in trauma patients. Urinary re­ of Defense or its components, to include the US Army and US
tention in the setting of spinal trauma can be caused by neuro­ Air Force, or the US Government.
genic bladder or acute compression of the spinal cord.
32
The first step in treatment of urinary obstruction is decom­ References
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