Renal Flashcards
During a TURP procedure under spinal anesthesia, a patient develops sudden pain in his left shoulder. He begins sweating then complains of nausea. Of the following options, which is the most likely?
When TURP procedures are done under spinal anesthesia up to T10 level and not deeply sedated, bladder perforation can be recognized by abdominal pain (and TURP syndrome can be recognized by CNS symptoms).
Which of the following crystalloid solutions MOST closely matches the composition below?
The described crystalloid is dextrose 5% in 1/2 normal saline (D5 1/2NS) solution; has an osmolarity of 406 mEq/L; and contains 77 mEq/L sodium, 77 mEq/L chloride, and 50 g/L glucose
Which of the following statements about succinylcholine administration and chronic renal insufficiency is TRUE?
Succinylcholine can be safely administered to normokalemic patients with renal failure as the rise in serum potassium is similar to that of normal healthy patients. The typical rise in serum potassium after administration of succinylcholine is 0.5 mEq/L. This generally normalizes within 10-15 minutes.
A 78-year-old man with chronic renal insufficiency and no other medical history presents to the hospital with chest pain. A diverse differential diagnosis is considered, including pulmonary embolism. Vital signs are within normal limits. An assistant asks you about a computed tomography scan to evaluate for pulmonary embolism. If the primary goal is to reduce the risk of contrast-induced nephropathy in this patient, which is likely the MOST important?
Prevention of contrast-induced nephropathy starts with proper patient selection and avoidance of contrast agents in high-risk patients. In those who still require the study and contrast administration, intravenous fluids hydration with normal saline and/or sodium bicarbonate is the most appropriate method. Additionally, the use of the smallest amount of contrast will be beneficial.
Which of the following MOST likely places a patient at risk for bradycardia following succinylcholine administration?
Repeat administration (e.g. an additional dose given within five minutes of an initial dose) and young age are the greatest risk factors for bradycardia with succinylcholine use. Bradycardia with repeat administration is a result of myocardium being sensitized by metabolic products of succinylcholine.
TrueLearn Insight : Patients with renal failure are not susceptible to exaggerated release of potassium, and succinylcholine can be safely administered to these patients, assuming that they do not have uremic neuropathy or critically elevated serum potassium levels.
Ketorolac is potentially nephrotoxic due to which of the following mechanisms?
Prostaglandins typically vasodilate afferent glomerular arterioles leading to increased glomerular capillary perfusion pressure. Nonsteroidal anti-inflammatory drugs are potentially nephrotoxic because they inhibit the production of prostaglandins. The nephrotoxic effects of NSAIDs may be exaggerated in hypovolemic patients.
A 72-year-old male is in the ICU on postoperative day 8 following sigmoidectomy with end colostomy for acute diverticulitis. Arterial blood gas on room air shows: 7.28/32/93. Lab values include:
Plasma sodium: 140 mEq/L
Plasma chloride: 114 mEq/L
Plasma bicarbonate: 16 mEq/L
Which of the following is the LEAST likely cause of the patient’s laboratory abnormalities?
Calculating the anion gap can help narrow down the etiology of a metabolic acidosis. Anion gap = serum sodium – (serum chloride + serum bicarbonate). Nonanion gap metabolic acidosis (where the anion gap is normal at 8-12 mEq/L) is typically caused by chloride-containing acid administration, increased HCO3- loss or loss of HCO3- precursors, or decreased renal acid excretion.
Bowel ischemia, especially in the setting of liver and/or renal failure, can cause a significantly increased serum lactate leading to a high anion gap acidosis.
Which of the following is NOT an effect of fenoldopam?
Fenoldopam is a selective D1 receptor agonist with direct natriuretic and diuretic properties. Fenoldopam promotes an increase in creatinine clearance and has been employed as a renal protector when renal vasoconstriction is anticipated.
Which of the following is the typical increase in serum potassium levels following succinylcholine administration in a patient with end-stage renal failure?
Serum potassium levels increase approximately 0.5 mEq/L after succinylcholine administration and normalize within 10-15 minutes in normal individuals. The same is seen in patients with chronic renal failure. This rise may be larger, and lethal, in patients with denervation injuries, muscular dystrophies, stroke, burns, or trauma due to diffuse up-regulation of extrajunctional acetylcholine receptors.
In the setting of acute hypoperfusion of the juxtaglomerular apparatus, which of the following BEST estimates the time before significant levels of angiotensin II are present?
Angiotensin II (A2)-mediated vasoconstriction is produced within 20 minutes after the onset of acute hypotension or hypovolemia. The release of A2 is modulated by the renin-angiotensin-aldosterone system (RAAS). Blockade of the RAAS by angiotensin-converting enzyme inhibitors or angiotensin receptor blockers may cause profound and refractory perioperative hypotension, particularly after induction of general anesthesia.
A 60-year-old female is being seen preoperatively prior to right total knee arthroplasty. She endorses symptoms of dyspnea on exertion, orthopnea, and fatigue. You order an echocardiogram which shows dilated cardiomyopathy with global hypokinesis of the left ventricle, EF of 30%, and mild central mitral regurgitation. The cardiologist plans to place her on low dose lisinopril. Which of the following changes are MOST likely to occur with lisinopril?
Angiotensin II results in increased inotropy, chronotropy, catecholamine release, catecholamine sensitivity, aldosterone levels, vasopressin levels, and cardiac remodeling through AT1 receptors. ACE inhibitors and ARBs help to prevent the remodeling that occurs secondary to angiotensin II and are beneficial in congestive heart failure.
A 71-year-old man with end-stage renal disease undergoes hemodialysis prior to an elective surgery. Which of the following is MOST likely to occur as a result of the dialysis?
The semipermeable membrane used in hemodialysis permits only small molecules including water, electrolytes, minerals, and salts to cross, according to their concentration gradients. The composition of the dialysate determines which substances move from blood to the dialysate, and vice versa.
A 58-year-old female with type 2 diabetes undergoes a robotic-assisted laparoscopic hysterectomy, complicated by mild hypotension. During the first six hours postoperatively, she is oliguric with urine output 0.2 mL/kg/hr. Serum chemistry shows sodium 140 mEq/L, potassium 4.5 mEq/L, BUN 42 mg/dL, and creatinine 2 mg/dL. Random urine chemistry shows sodium 20 mEq/L, creatinine 60 mg/dL. Which of the following is the MOST LIKELY etiology of the patient’s oliguria?
Causes of oliguria and AKI are organized into three categories: prerenal, intrinsic renal, and postrenal. See the above table for laboratory tests that can differentiate between the causes. Know how to calculate FENa: [(PCr x UNa ) / (PNa x UCr)] x 100.
A 70-year-old man presents for a left-arm arteriovenous fistula in anticipation of dialysis for end-stage renal disease. In addition to the risk of hyperkalemia, which of the following is most expected in a patient with end-stage renal disease?
Changes seen in end-stage renal disease include the following: Anemia Hypocalcemia Hyperkalemia Hypermagnesemia Hyperlipidemia Hypertension Hyperphosphatemia Secondary hyperparathyroidism Uremic bleeding diathesis
Which of the following crystalloid solutions MOST closely matches the composition below?
3% Hypertonic saline has an osmolarity of 1026 mEq/L and contains 513 mEq/L sodium and 513 mEq/L chloride.
