Fluid absorption during transurethral resection.

Abstract

During transurethral prostatectomy 1-5% glycine in water is commonly used to irrigate the bladder. Absorption of small quantities of this solution is inconsequential. Occasionally, however, large amounts may be absorbed, leading to severe hyponatraemia. Such severe sodium depletion is associated with electrocardiogram (ECG) changes that include a widened and increased amplitude of QRS complex, T wave inversion," and bradycardia. We report on three patients in whom absorption of irrigation fluid during transurethral resection of the prostate led to the death of one and cardiovascular collapse in the other two. Case reportsThree patients aged 76, 62, and 75 admitted with acute retention of urine were treated initially by urethral catheterisation. They were otherwise fit patients, but in one (case 3) the ECG showed ST depression in V4-6 compatible with myocardial ischaemia. All underwent transurethral resection of benign prostate with the Travenol Intermittent Irrigation System using 1-5% glycine solution.Case 1-After roughly 30 minutes of resection under general anaesthesia, during which 18 g of prostatic tissue was removed, the patient's pulse rate fell to 35/min and systolic blood pressure to 60 mm Hg. Myocardial infarction was diagnosed and 1 mg intravenous atropine and 2 units of blood were given without effect, and asystole followed. Cardiac resuscitation failed. Necropsy examination did not show the cause of death. A venous blood sample taken during bradycardia had a sodium concentration of 86 mmol(mEq)/l (normal range 132-144 mmol/l(mEq)/l). Plasma glycine concentration was 80 mmol/l (600 mg/100 ml) (normal range 0-162-0-335 mmol/l; 1-22-2-52 mg/100 ml).Case 2-Under spinal anaesthesia 60 g of prostatic tissue was resected in one hour, and during this the patient became confused and disorientated. The pulse fell to 50/min, and systolic blood pressure fell to 80 mm Hg. A clinical diagnosis of hyponatraemia was made and a blood sample taken for immediate electrolyte analysis. A total of 300 ml of 8-4% sodium bicarbonate was given followed by 1 5 litres of Hartmann's solution. Frusemide 40 mg was given intravenously when the systolic blood pressure had risen to 100 mm Hg. The patient's mental state improved rapidly with this treatment. Blood taken at the time of the diagnosis of hyponatraemia and three hours later showed sodium concentration of 107 and 130 mmol(mEq)/l respectively.The plasma glycine concentration was 50 mmol/l (375 mg/ 100 ml) in the initial blood sample. The total bicarbonate concentration was 32 mmol(mEq)/l (normal range 23-32 mmol (mEq)/l) in the second sample.Case 3-Under general anaesthesia a total of 35 g of prostatic tissue was resected in one hour. The patient was then sent to the recovery room and roughly 10 minutes later had a respiratory arrest, with a bradycardia of 50/min. He was intubated and resuscitated with 200 ml of 8-4% sodium bicarbonate and 2 units of blood. An ECG tracing at this time showed ventricular ectopics, right bundle-branch block, and deep T wave inversion in V4-6...

Hyponatraemia

“…Postoperative hyponatraemia is a frequent and potentially dangerous complication in adults (Ayus et al, 1992), and is usually secondary to inappropriate hypotonic¯uid replacement, though plasma vasopressin concentration may also be increased in the postoperative period (Chung et al, 1986). Irrigation of the bladder with hypotonic glycine solutions during transurethral resection of the prostate can lead to direct absorption of water from the bladder into the venous circulation, producing dilutional hyponatraemia (Osborne et al, 1980). Hypothyroidism is associated with increased total body sodium (Surveyor, 1963), and although hyponatraemia is reported in up to 10% of hypothyroid patients with normal renal function (Montengro et al, 1996), symptomatic hyponatraemia is rarely seen in clinical practice.…”

The syndrome of inappropriate antidiuretic hormone: prevalence, causes and consequences

“…SIADH needs to be distinguished from other causes of euvolaemic hyponatraemia, such as inappropriate hypotonic fluid replacement, particularly in patients following surgery. Hyponatraemia has also been reported to occur as a direct result of surgical procedures; for example, bladder irrigation with hypotonic solutions during transurethral resection of the prostate gland can lead to direct absorption of water from the bladder, producing euvolaemic dilutional hyponatraemia (17,18). Euvolaemic hyponatraemia may also occur due to inappropriate fluid replacement after exercise (19) or diarrhoeal illness.…”

The Pathophysiology, Diagnosis and Therapy of the Transurethral Resection of the Prostate Syndrome

“…However, in the presence of prostatic capsula perforation, the critical pressure for irrigating fluid absorption is less than the pressure required for intravascular system absorption [14]. The risk of TURP-S is higher when the endoscopic procedure lasts for more than 60 min [15,16]. This reinforces the need for a correct indication to perform a TURP, in terms of the size of the adenoma, as therapy for benign prostatic hyperplasia.…”