Size: 1 MB - TURP - anaesthetic concerns

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ANAESTHETIC MANAGEMENT OF TURP
Dr. S. Parthasarathy
MD., DA., DNB, MD (Acu),
Dip. Diab. DCA, Dip. Software statistics
Ph.D. (physiology)
Mahatma Gandhi medical college and research institute
, puducherry – India
HOW COMMON ??
• Approximately 40 000 transurethral resections
• of the prostate (TURP) are performed annually
• in the UK.
• In pondicherry
• 60 – 70 / month
PROSTATE NERVE SUPPLY
• The prostate and
prostatic urethra receive
sympathetic and
parasympathetic supply
from the prostatic plexus
arising from the pelvic
parasympathetic plexus,
which is joined by the
hypogastric plexus
NERVE AND BLOOD
• Pain from prostate – sacral nerves S2 –S4
• But bladder distension – sympathetic – T11 – L 2
• It has a rich blood supply and venous drainage
is via the large, thin-walled sinuses adjacent to
the capsule.
PROCEDURE
• The operation is performed through
a modified cystoscope
• • Prostatic tissue is resected using
an electrically energized wire loop.
• • Bleeding controlled coagulation
current.
• • Continuous irrigation is
necessary to distend the bladder
and to wash away blood and
dissected prostatic tissue.
PREOP - SYSTEMIC ILLNESS
•
•
•
•
•
Age – 69
Diabetes, musculo skeletal ,
Neuro, renal
CVS
GI ,COPD , airway
• Occasionly patients are dehydrated and depleted of
essential electrolytes (long-term diuretic therapy and
restricted fluid intake).
PREOP EVALUATION
• Lab investigations , ECG ,CxR
• Urine analysis – infection
• Antibiotic prophylaxis
• Blood gases, echo if needed
• Blood grouping – remember 6 %
• Anemia large glands > 40 G
DRUGS
• antihypertensive and antianginal drugs
should be continued until the day of
surgery.
• Beta blockers
• ACE inhibitors
• Bronchodilators
• Anti diabetic drugs
• Warfarin
PREMEDICATION
• Antibiotics,drugs and benzodiazepines
• Anesthesia
• Regional / GA
ANESTHESIA
• Spinal anaesthesia is regarded as the technique
of choice for TURP
• 2.5–3.0 ml of 0.5% plain or hyperbaric
bupivacaine may be used.
• Level T 10
• Why ??- bladder, capsular sign !!
• Why spinal ??
FOR SPINAL
• for patients with significant respiratory disease.
• good postoperative analgesia , blood loss less
• may reduce the stress response to surgery.
• spinal anaesthesia allows the anaesthetist to
monitor the patient’s level of consciousness, which
makes it easier to detect the early signs of TURP
syndrome.
• Early recognition of capsular tears and bladder
perforation is also possible
TIPS ABOUT SPINAL
• Intraoperative fluid overload less
• DVT less
• Use vasopressors for hypotension – add fentanyl.
• Technically easy than epidural
• Sacral sparing – no
• USE NS than RL – more osmolar and more sodium
• Warm IVF
•
GENERAL ANAESTHESIA
• Contraindication to spinal
• Cant lie down for longer times
• Cough during lying down.
• ETT or proseal LMA
• Dilutional hyponatremia – prolong NM blockers
• Post op caudal
• Rarely done under LA
LITHOTOMY
• Significant amount of intravascular volume is added to
the central circulation.
• Perfusion pressure of lower extremities = 10 – 15
mmHg – compression – compartment syndrome
• Nerve compressions
• Respiratory changes
POSITION – LITHOTOMY
IT CAN HAPPEN !!
• Under light planes of general anesthesia, penile
erection may interfere with surgery.
• It can usually be managed by deepening
anesthesia.
• Spinal anesthesia does not always prevent this
complication.
Irrigation fluid
THE IDEAL IRRIGATION FLUID
• is transparent (for good visibility),
• electrically non-conductive (to prevent dispersion of the
diathermy current),
• isotonic, non-toxic
• non-haemolytic when absorbed,
• easy to sterilize, inexpensive.
• However, no solution fulfils all of these criteria.
SOLUTIONS- OSM. ADV. AND DISADV.
• Distilled water 0 visible but hemolysis
• Glycine (1.5% - 2%) 200 visual
• Sorbitol (3%)
• Mannitol (5%)
165
275
• Glucose( 2.5%) 140
• Urea ( 1%)
167
hyperglycemia, diuresis
diuresis, overload
hyperglycemia
TURP SYNDROME
DEFINITION
• Constellation of some symptoms , signs
• excessive absorption of irrigating solution
• Direct intravascular access
• Thro perivascular spaces
• Changes in volume, electrolytes, osmolarily
•
Asymptomatic hyponatremia has been
• observed in 50% of patients undergoing
TURP
HOW MUCH AND WHEN
• 1–8%
• 15 minutes to after 24 hours
• Direct vascular or bladder rupture and absorption
• Mortality around 0.2% - 0.8%
CLINICAL FEATURES
• Acute fluid overload --- hypertension and reflex
bradycardia
• Later on equilibration from ECF, hypotension and
hypovolumia
• Sympathetic block of spinal
• Can precipitate pulmonary edema
CLINICAL FEATURES
• When glycine 1.5% is used as the irrigation fluid, early
features restlessness, headache, and tachypnoea,
• or a burning sensation in the face and hands.
• Visual disturbance including transient blindness
• increasing severity include respiratory distress,
hypoxia, pulmonary oedema, nausea, vomiting,
confusion, convulsions, and coma.
HYPOOSMOLALITY
• Hypoosmolality is more important than
hyponatremia
• 2[Na+] + [Glucose]/18 + [ BUN ]/2.8
• Effective pore size of BBB is 8 A – permeable to
water than sodium
HOW MUCH FLUID
• 8 L of irrigation solution can be absorbed by the patient
during TURP.
• The average rate of absorption is 20 mL per minute may
reach 200 mL per minute;
• the average weight gain by the end of surgery is 2 kg
• Ethanol 1%, electrolytes (Mg).CVP etc – volume absorbed
FACTORS
• Hypotensive, hypovolumic – more
• Capsule perforation – more
• Resection time
• Fluid bag , 30 cm from operating table height
• Blood loss
• Large prostate (>50 G)
IN A STUDY OF 117 CASES.
GLYCINE
• Nonessential amino acid
• NMDA receptor activity is potentiated by glycine
• Metabolized to gly oxalic acid and ammonia
• Ammonia – transient blindness
• Oxalate – precipitation of renal failure
• Redistributed in 6 min
• Half life 40 min to a few hours.
• Normal plasma levels 13- 17 mg/l.
WHAT MEANS TURP SYNDROME IN GA ??
• in the anaesthetized patient the only clue may be
tachycardia and hypertension.
• • diagnosis can be confirmed by finding a low serum
sodium.
• An acute fall to < 120 mEq/L is always symptomatic.
• Osmolarity more important than sodium
SERUM SODIUM
• 120 - confusion – wide QRS
• 115 – somnolence , nausea – st elevation +
T inv.
• 110 seizures , coma – V tach
INDICATORS OF VOLUME GAIN
• Ethanol 1% added to fluid and measurement of breath
alcohol level.
• Weight gain
• Serum sodium
• CVP trend etc.
HYPER AMMONEMIA
• Possible CNS symptoms
• 4 gm of l arginine infused in 3 minutes
decreases ammonia
• l arginine – 950 mosm / Kg
MANAGEMENT OF TURP SYNDROME
• Stop surgery
• Oxygen,
ventilation,
inotropes
anticonvulsants
diuretics
• Invasive monitors in selected cases.
• exerts a negative control on the NMDA receptor and also
having a membrane-stabilizing effect, and magnesium
therapy should be considered as part of the therapy for
seizures in TURP syndrome.
INVESTIGATIONS
• Blood , BUN, glucose , ABG , electrolytes
• CXR, ECG, Hematocrit
• Severe cases of symptomatic hyponatremia
• 3 % hypertonic saline 2 * 0.6 * Weight
• 2 *42 = 84 ml of 3% hypertonic saline – I meq. / l
• I F we correct fast –
• Osmotic demyelination syndrome.
INTRAOPERATIVE
• Myocardial ischaemia - can occur in up to 25% of
patients during TURP, with myocardial infarction
occurring in 1-3%
• Hypothermia.. Warmed irrigation fluid has NOT been
shown to increase blood loss by local vasodilation.
• warm i.v. fluids, active patient warming
devices.
• • Perforation of prostatic capsule, urethra or bladder with
the resectoscope.
• • Bleeding
BLOOD LOSS
• blood loss should lie within the range of 7-20 ml
per gram of resected tissue.
• Or
• 2 - 5 ml / minute
FACTORS - 1 %
• Large gland
• Time , Infection
• Pre op catheter
• TRANEXAMIC ACID 15 MG / KG - useful
• Prostate can release thromboplastin to cause
fibrinolysis. -- EACA
BLADDER PERFORATION
• Peri umbilical pain
• Hypotension sweating restlessness
• Hiccups
• Rarely shoulder pain
• Spinal identifies
POST OPERATIVE PROBLEMS
• Pain – not severe .- rare use opioids
• Bladder spasm
• Clot retention –
• precipitate bradycardia
• TURP syndrome
• Cognition impairment
DVT AND PE
• compression stockings are usually adequate as
prophylaxis.
• Low-molecular-weight heparin should be considered in
patients at higher risk
• (poor mobility, malignancy, inter current illness, and
obesity).
SUMMARY - TURP
• High number
• Preop disease , antibiotics
• spinal , level, Position ( GA / LA)
• TURP syndrome – irrigation fluid 20 ml/ min., factors
• Hypoosmolarity – NS , inotropes, stop surgery
• Blood loss, perforation bladder
• Pain ??
THANK YOU ALL
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