Renal Syndromes & Drugs Flashcards
What is Uremic Syndrome?
-Extreme form of chronic renal failure with surviving nephron population and GFR dropping to < 10%
-Reflects kidneys inability to perform functions of water and electrolyte balance
-BUN indicator of severity (Serum creatinine poorly correlates with S/Sx)
What are S/Sx of Uremic Syndrome?
Anorexia
nausea/vomiting
pruritus
anemia
fatigue
coagulopathy
What is the treatment for Uremic Syndrome?
Dietary protein restriction based on presumption that low protein diet results in decreased protein catabolism and urea production
What are complications of Uremic Syndrome?
Hyponatremia
Hyperkalemia
Metabolic acidosis
Heart failure
HTN
Myocardial dysfunction
Pulmonary edema
Central hyperventilation
Anemia
Delayed gastric emptying
Encephalopathy
Seizures
What is Nephrolithiasis?
Stone formation
-Pathogenesis poorly understood
-Most are Calcium Oxalate
-Stones in renal pelvis = painless
-Stones in ureters = painful
-Hematuria is common during passage of stone
-Ureteral obstruction leads to S/Sx of renal failure.
-Risk of sepsis due to buildup of waste products due to urine obstruction.
What is an S-Wall procedure?
Breaks up a kidney stone.
-Special OR table that beats against back, sending US wave into kidney to break up stone.
-Can cause irritation to heart. Leads to arrhythmias. Risk of R on T.
-Can synch this with the EKG.
What is TURP Syndrome?
TURP = Transurethral Resection of the Prostate.
-Syndrome occurs when patient absorbed too much of the irrigation fluids during the procedure.
-Intravascular fluid volume shifts and plasma solute effects
-Solute changes may alter neurological function independent of volume related effects
-Mild to severe
What are the S/Sx of TURP Syndrome? (general)
Related to water intoxication:
-Mild: Restlessness, nausea, shortness of breath, dizziness
-Severe: Seizures, coma, HTN, bradycardia, CV collapse
What are the disadvantages of the Glycine 1.5% solution used for TURP?
Hyperglycinemia
Hyperammonemia
-These cause the TURP Syndrome S/Sx
What are the Cardiovascular S/Sx of TURP Syndrome?
-Hypertension
-Reflex bradycardia
-Pulmonary edema
-Cardiovascular collapse
-ECG changes (wide QRS, elevated ST segment, ventricular arrhythmias)
What are the causes of the CV S/Sx in TURP Syndrome?
-Rapid fluid absorption
-Reflex bradycardia (secondary to hypertension or increased ICP)
-Third-spacing secondary to hyponatremia and hypo-osmolality
What are the Respiratory S/Sx of TURP Syndrome?
-Tachypnea
-Hypoxemia
-Cheyne-Stokes breathing
Caused by Pulmonary Edema
What are the Hematologic S/Sx of TURP Syndrome?
-Disseminated intravascular coagulation
-Hemolysis
Caused by Hyponatremia and Hypo-osmolality
What are the Neurological S/Sx of TURP Syndrome?
Nausea
Restlessness
Visual disturbances
Confusion
Somnolence
Seizure
Coma
Death
What are the causes of Neurological symptoms with TURP Syndrome?
-Hyponatremia and hypo-osmolality causing cerebral edema and increased ICP,
-Hyperglycinemia (glycine is an inhibitory neurotransmitter that potentiates NMDA receptor activity)
-Hyperammonemia
What are the Renal effects of TURP Syndrome?
Renal Failure.
Caused by Hypotension and Hyperoxaluria (Oxalate is a metabolite of glycine)
What are the Metabolic effects of TURP Syndrome?
Acidosis.
Caused by deamination of glycine to glyoxylic acid and ammonia.
What are factors that affect the Absorption of the fluids during TURP?
-Number and size of open venous sinuses (resection of prostate opens venous sinuses)
-Duration of resection
-Hydrostatic pressure of the irrigating fluid (height of bag on IV pole)
-Venous pressure at the irrigant-blood interface.
Rate of absorption determines whether or not we see syndrome.
How do you avoid absorption of the fluid during TURP?
-Resection time < 1hr
-Bag no > 30cm from bed at beginning and 15 cm during final stages of resection
-Avoid hypotonic solutions
-Treat Regional Anesthesia induced HOTN (use spinals with these)
What is the treatment for TURP Syndrome?
-Ensure oxygenation and circulatory support.
-Notify surgeon and terminate procedure as soon as possible.
-Consider insertion of invasive monitors if cardiovascular instability occurs.
-Send blood to laboratory for evaluation of electrolytes, creatinine, glucose, and arterial blood gases.
-Obtain 12-lead electrocardiogram.
-Treat mild symptoms (with serum Na+ concentration >120 mEq/L) with fluid restriction and loop diuretic (furosemide).
-Treat severe symptoms (if serum Na+ <120 mEq/L) with 3% sodium chloride IV at a rate <100 mL/hr.
-Discontinue 3% sodium chloride when serum Na+ >120 mEq/L.
What are the advantages to using Neuraxial Anesthesia for TURP?
-Ability to assess the patient’s level of consciousness for TURP syndrome
-Ability to assess chest pain, SOB caused by myocardial ischemia and volume overload
-Ability to assess abdominal pain caused by bladder perforation
-Decreased vascular resistance will less possibility of hypervolemia
-Controversial if neuraxial blockade decreases blood loss during TURP
What are the disadvantages to using Neuraxial Anesthesia for TURP?
-Moderate to severe HOTN can occur and potentiated in patients taking alpha-adrenergic antagonists for BPH
-Placement can be difficult due to arthritic changes in aging population
-Decreasing venous resistance increases amount of irrigant that is absorbed through open venous sinuses
-Dysphoria from benzos, narcotics or other CNS depressants given
What is the difference between Extraperitoneal and Intraperitoneal Bladder Rupture?
-Extraperitoneal is most common type (80% of cases) - usually secondary to adjacent pelvic fracture or avulsion tear
-Intraperitoneal usually iatrogenic or secondary to penetrating injury.
-Blunt trauma more likely to result in intraperitoneal rupture in children than in adults
-Intraperitoneal rupture requires surgical repair and extraperitoneal rupture can be treated conservatively
-Intraperitoneal rupture can develop chemical peritonitis
What are the S/Sx of Extraperitoneal Bladder Rupture?
Discomfort:
-Periumbilical
-Inguinal
-Suprapubic
Periumbilical/inguinal tissue distension
What are the S/Sx of Intraperitoneal Bladder Rupture?
Discomfort:
-Chest
-Upper abdomen
-Shoulder tip (diaphragmatic irritation)
Nausea and vomiting
Abdominal rigidity (if peritonitis develops)
Shortness of breath
Diaphoresis
Hiccups
Definitely requires surgical repair
What is the effect of Volatiles on Renal Function?
-Methoxyflurane & enflurane: Only volatiles to directly cause renal dysfunction
-Indirect effects combined with hypovolemia, shock, nephrotoxin exposure produce renal dysfunction
-Iso & Des have no impact
-Sevo is questionable with Compound A (not rly based in literature). Keep to 2 MAC hours.
Which is better for kidney function, GA or RA?
No studies show improved outcome/protection with either.
What is the effect of Thiopental when used in a patient with renal failure?
-Historic agent (Barbiturate)
-Free fraction of an induction dose of thiopental is almost doubled in patients with renal failure
-Severe hypotension
What is the effect of Ketamine when used in a patient with renal failure?
-Less extensively protein-bound than thiopental, and renal failure appears to have less influence on its free fraction
-Don’t use for induction of GA with renal patients
-However, can be used in pain mgmt of renal patients. 30-50 mg, or small drip of it for short period of time is helpful. Subclinical doses so don’t get hallucinogenic effects
-Provides dissociative amnesia and patient keeps breathing.
What is the effect of Etomidate when used in a patient with renal failure?
-75% protein-bound in normal patients, has a larger free fraction in patients with ESRD.
-Cardiac protective drug.
-Good to use with ESRD due to maintaining cardiac stability.
What is the effect of Propofol when used in a patient with renal failure?
-Rapid hepatic biotransformation to inactive metabolites that are renal excreted
-Dose dependent: can use it, but maybe lower dose
-Patients will respond like a hypovolemic state. Labile VS
What is the effect of Benzos when used in a patient with renal failure?
-CKD increases the free fraction of benzodiazepines in the plasma, and this potentiates their clinical effect
-Decrease the dose
What is the effect of Dexmedetomidine when used in a patient with renal failure?
-Primarily metabolized in the liver
-Pretty safe in renal patients
-effects may last longer (prolonged)
What is the effect of Morphine when used in a patient with renal failure?
-Single-dose studies demonstrate no alteration in its disposition
-Chronic administration results in accumulation of its metabolite, leading to potent analgesia and sedation.
What is the effect of Meperidine when used in a patient with renal failure?
Not recommended for use in patients with poor renal function.
-Metabolites can accumulate
What is the effect of Codeine when used in a patient with renal failure?
Can be used short-term, but not prolonged use.
-Potential for causing prolonged narcosis
What is the effect of Fentanyl when used in a patient with renal failure?
Better choice of opioid for use in ESRD because of its lack of active metabolites, unchanged free fraction, and short redistribution phase.
What is the effect of Alfentanil when used in a patient with renal failure?
No change in its elimination half-life or clearance in ESRD and is extensively metabolized to inactive compounds.
What is the effect of Remifentanil when used in a patient with renal failure?
Renal failure has no effect on the clearance of remifentanil, but elimination of the principal metabolite, remifentanil acid, is markedly reduced.
What is the effect of Muscle Relaxants when used in a patient with renal failure?
-Most likely to produce prolonged effects
-Most are dependent on renal excretion
-Except: succinylcholine, atracurium, cis-atracurium, and mivacurium appear to have minimal renal excretion of the unchanged parent compound
Other factors:
-coexisting acidosis and electrolyte disturbances, as well as drug therapy
Succ:
-Be sure to check serum potassium levels
What is the effect of Long-acting Muscle Relaxants (Ex: Pancuronium) when used in a patient with renal failure?
Increased elimination half-life, reduced plasma clearance, and prolonged duration of effect.
-Avoid in Renal patients
What is the effect of Intermediate acting Muscle Relaxants when used in a patient with renal failure?
-Atracurium and cisat undergo Hoffman degradation (might be better choice)
-Vec duration of action prolonged
-Roc single dose study has reported conflicting reports
However, if using Vec or Roc can decrease dose or increase interval. Adequately monitor TOF. Patients will have abnormal rxns.
What is the effect of Short-Acting Muscle relaxants when used in a patient with renal failure?
Mivacurium is eliminated by plasma pseudocholinesterase at a rate slower than succ.
