Case 36 - TURP

Question 1

What is TURP Syndrome?

Answer 1

TURP = Transurethral Resection of Prostate

• Water intoxication, hyponatremia, hypoosmolality 2/2 excessive amounts of irrigating fluids absorbed through the opened prostatic venous sinusoids

Hyponatremia

• serum dilution secondary to irrigating solutions
• degree of hypo Na+ related to RATE OF ABSORPTION (not to absolute amount absorbed)

Question 2

What are the CNS effects of TURP syndrome?

Answer 2

Neurologic injury associated with rate of Na+ decrease rather than the degree of hyponatremia

• CNS effects secondary to cerebral edema with concomitant increase in ICP

CNS effects:

• h/a
• agitation / restlessness
• confusion
• seziures
• coma
• clonus
• papilledema

Question 3

What are the cardiovascular effects of TURP syndrome?

Answer 3

• CV effects are due to fluid overload and hyponatremia

Na+ < 120 meq/L

• negative inotropic effects
• hypotension
• pulm edema
• CHF

Na+ < 115 meq/L

• widened QRS
• ventric ectopy
• t-wave inversion

Na + < 110 meq/l

• cardiac and resp arrest

Question 4

How would you tx TURP syndrome?

Answer 4

• surgery should conclude ASAP
• ABC
• consider tracheal intubation and mech ventilation
• Tx - increase Na+ levels
  
  • fluid restrection
  • loop diuretics
  • severe cases/symptomatic hyponatremia may require hyper tonic saline solution (3% NaCl)
    
    • rapid correction of hyponatremia –> cerebral edema and cerebral pontine myelinolysis
• tx patient symptoms

Question 5

What are other complications of TURP?

Answer 5

Bladder Perforation

• extraperitoneal or intraperitoneal
• decrease return of irrigating fluids
• regional anes –> complain of abd pain, n/v

Bleeding

• related to size of gland and resection time
• prostate is vascular organ

Coagulopathy

• dilution of coag factors
• DIC

Transient bacteremia/septicemia

• prostate is rich in pathogens, can enter prostatic venous sinuoids into systemic circulation

Irrigating fluids toxicity

• hyponatremia
• fluid overload
• sorbitol and mannitol solutions –> lactic acidosis and hypergycemia

Hypothermia

• room temp irrigating fluids can cause this
• use warm fluids to decrease heat loss/shivering

Question 6

Anything you can do to minimize incidence of TURP Syndrome?

Answer 6

Main Goal: limit amount of irrigating fluids absorbed

• restrict height of irrigating fluid
  
  • will help decrease hydrostatic pressure driving fluid into sinuses
• limit resection to < 90 min
• restricting TURP to prostate glands < 45 g
• injeting intraprostatic vasopressin
  
  • vasoconstricts vessels and limits absorption of irrigant fluid

Question 7

What type of irrrigating solutions exist today?

Answer 7

• solutions include glycine and a mixture of sorbitol and mannitol

Question 8

What toxicities are associated with glycine?

Answer 8

Glycine toxicity

1) blindness

• inhibitor effect of glycine on CNS
  2) Hyperammonemia
• glycine is metabolized to ammonia
• symptoms: n/v, coma

3) myocardial depression

Question 9

Why may regional anesthesia be beneficial in a TURP patient?

Answer 9

1) early detection of TURP Syndrome
* allows to monitor mental status changes, irritability & h/a, early signs of hyponatremia

2) detection of bladder perf

• awake patient will complain of abdominal or shoulder pain despite sensory blockade

3) decrease blood loss

• decrease in BP in central and peripheral circulations

4) decrease incidence of DVT

• possibly due to decrease in stress response (promotes hypercoaguable state)
  5) post op analgesia

*GENA will hide s/sx of hyponatremia, bladder perf. bucking on tube will increase venous pressure leading to increase risk of bleeding*

Question 10

If regional anesthesia is selected, what level of anesthesia is required?

Answer 10

• level of anesthesia depends on anatomy and sensory of involved structures

T11 - L2

• bladder dome
• prostate

S2 - S4

• bladder neck
• prostate
• penis
• scrotum

Blockade to T10 level is sufficient.

epidural blockade may result in incomplete block of sacral nerve roots

Question 11

what is the sodium deficit equation?

Answer 11

Na+ deficit (mEq) = Total body water x (Na desired - Na observed)

Total body water = 0.6 x lean body weight (male)

total body water = 0.5 x lean body weight (female)

Question 12

What rate should you correct Na+ deficiency using hypertonic saline?

Answer 12

Na+ deficient:

• fluid restrict
• Lasix
• hypertonic saline (3% NaCl)

Hypertonic saline (3% NaCl)

• contains 513 mEq/L of Na+
• symptomatic hyponatremia: 3 mEq/L per hour to avoid cerebral pontine myelinolysis (CPM)

CPM

• sevre damage of myelin sheath of nerve cells in the Pons portion of brainstem
• can lead to acute paralysis, dysphagia, dysarthria