2. TURP syndrome
A combination of fluid overload and hyponatremia
This syndrome is far less likely with the use of bipolar
resectoscopes and saline irrigation.
Laser enucleation has virtually eliminated the risk.
3. Irrigation fluid must be
Non-conductive: so that the diathermy current is concentrated
at the cutting point
Non-hemolytic: so that hemolysis does not occur if it enters the
circulation, and
Must have neutral visual density: so that the surgeon’s view is
not distorted.
For these reasons, it cannot contain electrolytes but
cannot be pure water.
5. The amount of absorption depends upon the
following factors:
Pressure of infusion—the bag must be kept as low as
possible to achieve an adequate flow of irrigant at minimum
pressure, usually 60–70cm above bladder, never >100cm.
Higher pressures increase absorption
CVP—more fluid is absorbed if the patient is hypovolemic or
hypotensive
Long duration of surgery and large prostate—surgery
lasting >1hr or with a prostate weighing >50g
Blood loss—large blood loss implies a large number of
open veins.
6. Do not increase the risks of fluid overload by
giving an unnecessarily large volume of IV fluid.
Ensure that the irrigation fluid is changed to
saline in recovery to prevent further absorption of
hypotonic glycine.
7. Signs of pulmonary edema, cerebral edema, and
hyponatremia are the usual presenting features.
They will be detected earlier in the awake patient.
Mortality is high, unless recognized and treated promptly.
Early symptoms include restlessness, headache, and
tachypnoea, and these may progress to respiratory
distress, hypoxia, arrhythmias, pulmonary edema,
N&V, visual disturbances, confusion, convulsions, and
coma.
8. In the anaesthetized patient, the only evidence may be
tachycardia and hypertension.
Rapid absorption of a large volume can lead to reflex
bradycardia.
Hypotension can also occur.
The diagnosis can be confirmed by low serum Na+.
an acute fall to <120mmol/L is always symptomatic.
9. If detected intraoperatively:
Bleeding points should be coagulated,
Surgery terminated as soon as possible, and
IV fluids stopped.
Give furosemide, and check serum Na+ and Hb.
Support respiration with O2 or intubation and ventilation,
if required.
Administer IV anticonvulsants, if fitting.
Treat with hypertonic saline (NaCl 1.8–3%) :If serum Na+ is
<120mmol/l and associated with neurological signs
until serum Na+ is >120mmol/L
10. Obtain 12 lead ECG, electrolytes, ABG, HGb, measured
serum osmolality
Consider invasive hemodynamic monitoring if severe
heart failure
Monitor electrolytes q1h
Consider hemodialysis in symptomatic patients with
poor urine output
11. The volume of 3% saline (in mL) which will raise serum
Na+ by 1mmol/L is twice theTBW (in L).
TBW in men is about 60% of body weight, i.e. for a
70kg man:
CalculateTBW = 70 × 0.6 = 42L
Therefore, 84mL of 3% saline will raise serum Na+ by
1mmol/L
a volume of 1008mL of 3% saline over 24hr will raise serum
Na+ by 12mmol/L.
12. In practice, give 1.2–2.4mL/kg/hr of 3% saline until
symptomatic improvement.
This should produce a rise in serum Na+ of 1–2mmol/L/hr.
Correction should ideally not be faster than
1.5–2mmol/L/hr for 3–4hr, then
1mmol/L/hr until symptomatic improvement or Na+
>125mmol/L.
Maximum rise should not exceed 12mmol/L in 24hr.
Admit to ICU/HDU for management, including regular
measurements of Na+
13. Both severe acute hyponatremia and over-rapid
correction of chronic hyponatremia can result in
permanent neurological damage (most commonly
central pontine myelinolysis).
14. Treatment with hypertonic saline has been associated
with development of demyelinating CNS lesions (central
pontine myelinolysis)
this approach should be reserved for patients with severe, life-
threatening symptoms.
The demyelination is the result of excessive shrinkage of
brain cells after rapid hydration with hyperosmolar
solution,
because the brain cells have extruded important osmoles
to compensate for the chronic hypotonicity.
