Transurethral resection of the prostate, serum glycine levels, and ocular evoked potentials

Complications of transurethral resection of the prostate (TURP syndrome) when glycine is used as the irrigating fluid include cardiovascular and central nervous system abnormalities that occasionally include transient blindness. Serum sodium, glycine, potassium, chloride, ammonia, osmolality, carbonate, and blood urea nitrogen of 17 patients having TURP and 10 having cystoscopic examination were measured. Electroretinograms and visually evoked potentials (VEPs) were recorded in the preanesthetic preparatory area and in the recovery room immediately after surgery. Four patients reported visual aberrations coincident with increases in serum levels of glycine from a mean before surgery of 137.7 +/- 45.1 to 7,812.2 +/- 2,486.6 microM/l, mean +/- SD, after TURP. These patients also showed a reduction of serum sodium from 138 +/- 4.5 to 122 +/- 8.6 mEq/l that correlated significantly with serum levels of glycine (rho = -0.81). There were no statistically significant changes of serum ammonia and osmolality. Electroretinograms consistently demonstrated complete loss of oscillatory potentials. Thirty hertz flicker-following was also abolished. VEPs were more variably affected with prolongation of component "P100" latency found in both groups and probably resulting from sedative effects of diazepam. Patients experiencing the TURP syndrome showed abolishment of 30 Hz flicker-following in their VEPs. The elevated serum levels of glycine may contribute directly to visual aberrations resulting from glycine's role as an inhibitory transmitter in the retina.     

A comparison of the effect of 1.5% glycine and 5% glucose irrigants on plasma serum physiology and the incidence of transurethral resection syndrome during prostate resection

OBJECTIVE: To examine changes in the pathophysiology and frequency of the transurethral resection (TUR) syndrome with two irrigation fluids, as variable amounts of irrigation fluid are absorbed during TUR of the prostate (TURP), and although polar solutes are required to prevent an effect on diathermy, the solutes may have effects when absorbed. PATIENTS AND METHODS: Between December 2001 and March 2003, 250 patients were included in a prospective randomized trial comparing glycine 1.5% with 5% glucose irrigation fluids. We measured blood loss, fluid absorption, temperature change, biochemistry including a glycine assay, and peri-operative symptoms. Blood samples were taken immediately before and immediately, 5 and 24 h after TURP. Irrigating fluid absorption during TURP was measured with 1% ethanol as a marker and breath ethanol measurements. Operative details were recorded, including the type of anaesthesia (with or with no sedation), resection time and weight of resected tissue. Peri-operative symptoms were documented prospectively. TUR syndrome was defined as a serum sodium level of < or = 125 mmol/L with two or more associated symptoms or signs of TUR syndrome. RESULTS: Five (2%) patients had TUR syndrome; all five were irrigated with glycine, although this difference was not statistically significant (P = 0.06). Of the five men, three had hypotension, four were tired, one was nauseous, two had parasthesia, two had 'uneasiness', one had blurred vision and two were confused; none had chest pain. There was a large variation between the groups in the level of glycine assayed immediately after TURP; a high glycine level was associated with the TUR syndrome (P = 0.01). There was no difference between the groups in levels of sodium, potassium, urea, creatinine, osmolality, calcium, haematocrit, albumin serum levels or peri-operative blood loss (defined as a change from before to after TURP in haemoglobin level, accounting for transfusions). CONCLUSIONS: An increase in serum glycine was associated with TUR syndrome; there were large variations in the amounts of glycine absorbed, reaching levels many times the upper limit of normal. In other studies, glycine was reportedly toxic, and that the levels recorded were many times the upper limit of normal may have both immediate and long-term effects.     

Glycine solution as an irrigating agent during transurethral prostatic resection. Glycine concentrations in blood plasma

In 17 men undergoing transurethral resection of the prostate (TURP), an isosmotic solution of 2.2% glycine was used for irrigation. The plasma glycine concentration was determined before and immediately after TURP and 2, 6, 24 and 48 hours later. The serum concentrations of sodium, albumin and prostatic acid phosphatase protein (PAP) were used as indicators of fluid absorption. Calculation of the absorbed fluid volume was based on the plasma concentration of glycine, and the disappearance rate of glycine from plasma was estimated. The mean disappearance rate (T 1/2) was 85 min, which was midway between previously observed rates for sorbitol and mannitol. The observed plasma glycine increase after TURP correlated well with fall in serum sodium and rise in serum PAP, with the blood loss during and up to 15 min after TURP, and also with the weight of the resected tissue. The plasma glycine level, highest immediately after TURP, normalized 24-48 hours postoperatively. No signs of ammonia intoxication or marked serum urea increase were seen in these patients, although some had very high plasma glycine values after TURP (mean 10.2, maximum 23 mmol/l) as compared with the preoperative levels (mean 0.2 mmol/l). There was some increase of plasma serine (a normal metabolite of glycine) after TURP. The authors conclude that the irrigating fluid should have a minimal concentration of glycine, near to the level of haemolysis onset, to minimize the plasma dilution effects, including hyponatraemia, and the appearance of metabolites when the irrigating fluid is absorbed.     

持续中心静脉压监测在早期诊断前列腺电切综合征的临床意义

目的 观察经尿道前列腺电切术(transurethral resection of prostate,TURP)中中心静脉压(CVP)的变化情况,结合各时间点的电解质,渗透压及不良事件发生情况,探讨CVP监测在前列腺电切综合征(transurethral resection of prostate syndrome,T...     

The role of ammonia toxicity in the post transurethral prostatectomy syndrome

To investigate the aetiology of altered mental status following transurethral prostatectomy (TURP), serum electrolyte and blood ammonia levels were measured in 33 patients before and immediately after TURP. The irrigating fluid was 3% sorbitol in 12 patients and 1.5% glycine in 21. Serum electrolyte changes were similar in both groups. Elevated blood ammonia levels were observed in eight of the 21 patients receiving glycine irrigation. Three of these eight patients demonstrated clinical signs of encephalopathy. Absorption of glycine during transurethral prostatectomy appears to produce hyerammonaemia in some patients and may contribute to the encephalopathy.     

Spinal versus epidural anesthesia during transurethral resection of the prostate.

The operative superiority of epidural anesthesia during transurethral resection of the prostate (TURP) stimulated this study. Twenty patients scheduled for TURP were randomly allocated to receive either spinal anesthesia (n = 10) with 8 ml bupivacaine 0.5%+ 5ml lignocaine 2%. During and after the operative procedure, PR, BP, ECG, and pulse oximetry were monitored, and blood Hb and Hct, plasma free Hb, and serum sodium and potassium levels were measured. Both techniques resulted in similar PR and BP changes. TURP with spinal anesthesia resulted in more prolonged period of hyponatremia and more increased duration of raised plasma free Hb.     

Osmotic and metabolic sequelae of volumetric overload in relation to the TUR syndrome

In an attempt to understand the pathophysiology of the transurethral resection syndrome this prospective metabolic study was conducted on 100 consecutive patients undergoing transurethral resection of the prostate (TURP). The volume of glycine absorbed, intravenous fluid given and blood loss were calculated, and serum osmolality, sodium and glycine were measured before, during and after operation. The mean volume of glycine absorbed, fluid gain and blood loss were 0.6, 1.57 and 0.356 litres respectively. The mean weight of prostate resected was 30.8 g and resection time was 56.5 min. The mean serum osmolality dropped from 291 to 286 mOsm/l, sodium dropped from 138 to 132 mmol/l and glycine concentration increased from 293 to 3599 mumol/l post-operatively. Ten patients developed signs suggestive of the TURP syndrome. Multiple regression analysis showed that the most consistent statistically significant factors in relation to the syndrome were volumetric gain and hypo-osmolality. The latter proved to be the only significant factor later post-operatively. The increase in serum glycine and drop in serum sodium concentrations were the best serological markers, reaching significance only after excluding volumetric gain and osmolality from the analysis.     

Fluid and electrolyte dynamics during development of the TURP syndrome

Signs and symptoms, circulatory changes and the diffusion of fluid and electrolytes were examined over 10-min periods in the course of 12 transurethral resections of the prostate (TURP) during which more than 1 litre of glycine solution was absorbed. Signs of the TURP syndrome were seen in 10 patients. During the first 20 min of absorption there was hypervolaemia, a marked diffusion of electrolytes from the interstitial space to the plasma, and elevation of central venous pressure. Patients who developed hypertension (n = 6) and chest pains (n = 3) had a smaller blood loss than those who did not. After 20 min of irrigant absorption there was an increased flow of fluid from the plasma to the interstitial space coupled with only a small diffusion of sodium. This promoted hypovolaemia and hypotension.     

Effects of transurethral prostatectomy on nonelectrolyte components of serum

The total serum protein, serum albumin, serum globulin, and serum cholesterol were measured in 220 patients having transurethral prostate resection. The measurements were made before surgery, at the termination of the operative procedure, and on the first postoperative day. The changes observed showed a decrease in each parameter and were compared with serum sodium measurements made at the same time intervals. The per cent change that occurred intraoperatively in total serum protein was -14.5 per cent, serum albumin -14.5 per cent, cholesterol -14.4 per cent, globulin -12.9 per cent, while serum sodium was -2.6 per cent. On postoperative day 1, only serum sodium and serum globulin showed a significant change from the immediate postoperative value. Since plasma sodium readily equilibrates with the interstitial fluid while plasma proteins do not, plasma dilution may be reflected more accurately in measurement of changes in plasma proteins and cholesterol than measurement of serum sodium.     

ECG and cardiac enzymes after glycine absorption in transurethral prostatic resection

The electrocardiogram (ECG) was recorded and the serum levels of creatine kinase (CK), aspartate transaminase (ASAT) and prostatic acid phosphatase (PAP) were measured in 22 patients undergoing transurethral resection of the prostate (TURP) under spinal or epidural anaesthesia. The irrigating fluid consisted of 1.5% glycine and 1 % ethanol, and absorption of the fluid was monitored by detection of alcohol in the expired breath. The results show that nine of the 11 patients (82%) who absorbed more than 1, 000 ml of irrigating fluid had developed ECG changes 24 h after the operations. The most common alteration was depression of the T wave. This sign was only seen in one (9%) of the patients who absorbed none or very small amounts of irrigating fluid ( P < 0.001). The serum activity of CK and ASAT increased in five patients who also developed ECG changes, and the highest values were recorded 24 h after TURP. The CK–MB isoenzyme was detected in 85% of the samples with elevated total CK, but the criteria for myocardial infarction were never fulfilled. In contrast, PAP increased in all patients and the highest level occurred at the end of TURP. The activity–time profiles suggest that CK and ASAT entered the circulation by a mechanism different from that of PAP. We conclude that absorption of glycine solution during TURP is frequently followed by nonspecific ECG signs of altered cardiac function and also that the serum activities of CK and ASAT increase is some of these patients.     

Does intraprostatic vasopressin prevent the transurethral resection syndrome?

OBJECTIVE: To determine whether intraprostatic vasopressin (IPVP) prevents the transurethral resection (TUR) syndrome during prostatectomy. PATIENTS AND METHODS: The study comprised 36 consecutive patients (mean age 68 years) with prostates clinically assessed as >/= 20 g who underwent standard transurethral prostatectomy (TURP). Ten units of vasopressin in 0.5 mL were diluted with 9.5 mL isotonic saline and injected into the prostate transrectally before TURP. Blood samples were taken before and immediately after TURP to measure serum sodium concentration and free haemoglobin levels. The TURP irrigant used was cooled, boiled water maintained at 70-80 cmH2O pressure during resection. Twenty patients had alcohol added to the irrigant and their breath alcohol assessed at 10-min intervals during TURP. All patients had their pulse rate, blood pressure and sensorium monitored continuously. Extreme care was taken to avoid and/or identify capsular damage during resection. RESULTS: The mean weight of tissue resected was 36 g and the mean resection time 24 min. There was no significant change in clinical variables during TURP. In 19 patients the breath alcohol changes were insignificant. Changes in free haemoglobin were not significant, but the levels decreased after TURP in four patients, caused by the dilution consequent on the infusion of 800-1000 mL isotonic saline during surgery. Serum sodium concentrations showed only insignificant decreases, except in one patient whose breath alcohol suggested the absorption of 500 mL of irrigant. This patient's serum sodium concentration decreased by 9 mmol/L; 1 L of 5% dextrose was infused during the procedure and capsular damage was recognized early during TURP. CONCLUSION: Insignificant volumes of irrigant entered the circulation of the patients during TURP with water irrigation and IPVP. The greatest risk factor for fluid entry during TURP is capsular damage. IPVP decreases bleeding and therefore improves visibility, so allowing the early identification of capsular damage. IPVP seems therefore to be of help during TURP by decreasing bleeding and allowing insignificant volumes of irrigant to enter the vasoconstricted vessels; it appears to prevent the TUR syndrome.     

Transurethral resection syndrome. A prospective study.

Significant hyponatraemia has been reported following transurethral prostatectomy (TURP) in 11-41% of cases. The majority of previous studies have been performed retrospectively. A prospective study was undertaken of 100 patients undergoing TURP. In all, a 24-Charr sheath with non-irrigating, resectoscope and 1.5% glycine as irrigant was used. Volume of irrigant used, weight of prostate and length of procedure were recorded. Serum electrolytes were measured at anaesthetic induction and immediately on transfer to the recovery room. In none of the 100 patients was there a statistically significant fall in serum sodium following resection. No clinical changes of transurethral resection (TUR) syndrome occurred. This study confirms that TUR syndrome and a significant fall in serum sodium can be virtually prevented in TURP and the use of an irrigating resectoscope or a trocar in the average case is not necessary.     

PlasmaKinetic Superpulse transurethral resection versus conventional transurethral resection of prostate

PURPOSE: To compare the efficacy and safety of the PlasmaKinetic (PK) Superpulse system with that of conventional transurethral resection of the prostate (TURP) in terms of restoration of urinary flow and early postoperative course. PATIENTS AND METHODS: One hundred five men older than 45 years with lower-urinary tract symptoms associated with benign prostatic hyperplasia (BPH) were randomized, 51 undergoing standard TURP with glycine as the irrigation fluid and 53 TURP with the PK Superpulse system with normal saline as irrigant. The operative time, intraoperative blood loss, catheter time, change in serum electrolytes (particularly sodium), and uroflowmetry and American Urological Association (AUA) Symptom Scores were compared. RESULTS: The blood loss as well as the catheter time observed in the PK Superpulse arm were significantly less than those in the conventional-TURP arm. The mortality rate was 0 in both the arms. The mean operative time was less in the PK Superpulse arm, although not significantly so. Hyponatremia was statistically insignificant. Significant changes were observed in the AUA Scores in both arms. CONCLUSION: The PK Superpulse system provides faster removal of tissue in a bloodless field with better views and a safer environment of saline irrigation with efficacy comparable to that of conventional TURP. However, further randomized trials with extended follow-up may be needed to better define the role of the PK Superpulse system in treating patients with symptomatic BPH.     

Effects of distilled water and mixture of sorbitol-mannitol irrigation fluids on fluid-electrolyte balance in patients undergoing transurethral prostatectomy

This study aimed to compare two various irrigation fluids used in transurethral prostatectomy (TURP) with respect to changes in fluid-electrolyte balance and to evaluate the blood loss during TURP. TURP was performed in 50 patients using distilled water and in 42 patients using a mixture of sorbitol and mannitol solution (2.7% sorbitol and 0.54% mannitol) as irrigation fluid. Fluid-electrolyte changes and blood loss were evaluated. None of the patients had transurethral resection syndrome. Decline in serum sodium level was more significant in patients who were operated on with the sorbitol plus mannitol irrigation fluid in contrast to its clinical insignificance (p<0.05). Decrease in serum sodium concentration in patients with more than 15 g of tissue resected was greater than in patients with less than 15 g of tissue resected (p<0.05). Blood loss was, greater in the distilled water group (p<0.05). Blood loss was 145.5±3.4 ml in patients given a, blood transfusion. In conclusion, a fluid containing mainly sorbitol must be the irrigation fluid preferred over distilled water because of its non-haemolytic nature, but although not important clinically, it can cause hyponatraemia more than distilled water. Furthermore, it is useful to determine blood loss during TURP before deciding to give a blood transfusion.     

No evidence of fluid absorption during continuous low-pressure transurethral resection of the prostate: assessment by measuring expiratory breath ethanol concentrations.

OBJECTIVE: Measurement of the ethanol concentration in expired breath during transurethral resection of the prostate (TURP). METHODS: TURP is a noninvasive method to estimate the amount of irrigant absorbed. The expiratory breath ethanol concentrations (EBEC) were measured with a standard alcohol breath analyzer in 35 patients in the course of TURP. All interventions were performed with a 27-french continuous flow resectoscope using a solution of 1. 5% glycine + 1% ethanol as irrigating fluid. Serum sodium and osmolality were measured pre- and postoperatively. No patient developed signs of transurethral resection syndrome; no significant changes in serum sodium, osmolality and EBEC were found throughout the operation. CONCLUSION: Absorption of irrigant fluid during TURP with continuous low-pressure irrigation seems to be extremely slight (if not absent) as measured by expired breath ethanol method.     

TURP对BPH患者血清PSA水平的影响

目的:通过经尿道前列腺电切术(TURP)的BPH患者血清前列腺特异抗原(PSA)的近、远期变化,探讨TURP前后PSA变化的价值及PSA变化与切除程度的相关性。方法:前瞻性队列研究209例接受TURP的BPH患者术前、术后5天、术后1个月、术后3个月、术后半年的血清PSA水平变化及PSA变化与切除程度的相关性。结果:术前PSA水平为(9.82±9.60)μg/L,术后5天为(5.40±4.04)μg/L,术后1个月为(3.5±3.15)μg/L,术后3个月为(2.56±1.13)μg/L,术后半年为(3.47±1.04)μg/L。术后5天与术前相比,PSA下降约(4.42±8.78)μg/L,术后1个月降至术前的35%,5段时间PSA水平互相对比,差异均有统计学意义(P0.01)。PSA4μg/L组PSA下降后仍高于PSA≤4μg/L组。TURP的实际切除质量与应该切除质量相减的均数±标准差,总样本为(-0.941±9.56)μg/L,PSA≤4μg/L组为(0.13±10.53)μg/L,PSA4μg/L组为(-3.83±5.41)μg/L。PSA的变化与切除程度呈正相关(P0.01,R=0.91),并且PSA≤4μg/L组与PSA4μg/L组PSA的变化均与切除程度呈正相关(P0.01,1=0.986,R2=0.924),两组间差别无统计学意义。结论:PSA在TURP后呈下降趋势,于1个月左右降至正常水平,并且TURP切除的范围越足够,PSA下降的幅度越大。术后长期随访BPH患者TURP后血清PSA水平,能减少前列腺癌的误诊及漏诊。对于监测术前PSA4μg/L的BPH患者应以其术后自身PSA基线为准,衡量其前列腺穿刺活检的指征及前列腺癌的诊断。     

双极经尿道手术中葡萄糖作为冲洗液的吸收标记物

背景过去,血清钠离子浓度的降低是诊断经尿道前列腺切除术（transurethralresectionoftheprostate,TURP）冲洗液（不含电解质）吸收的诊断标准。在使用双极的TURP中,冲洗液包含了电解质,所以不能依赖血钠浓度来判断冲洗液是否吸收。在本研究中,我们观察了在使用双极的TURP手术中葡萄糖能否成为冲洗液吸收的诊断标准。方法选取250例使用单极行TURP手术的患者,术中膀胱冲洗液为1．5％的甘氨酸或5％的葡萄糖溶液,检测血糖和血钠浓度。选取10名志愿者,持续输注含1％葡萄糖的醋酸林格液（20ml／kg）30分钟,进行葡萄糖代谢动力学分析。计算机通过采集的数据模拟出不同的吸收模式,以列线图总结出葡萄糖浓度和输注液体容量的关系。结果在TURP中5％葡萄糖灌洗液冲洗后,血钠降低,血糖升高,呈明显的负线性关系（r2=0．80）。在冲洗过程中血糖逐渐升高,从4．6（标准差0．4）mmol／L升高至8．3（0．9）mmol／L。无论何种吸收模式均显示体内摄取1L含1％葡萄糖的冲洗液血糖相应的升高3．7（SD1．6）mmol／L,摄取2L冲洗液血糖升高6．9（1．7）mmol／L。结论在使用单极的TURP中,通过检测血钠浓度来观察冲洗液吸收情况,与之相比较,在使用双极的TURP中,含有电解质的冲洗液中加入1％的葡萄糖,可以成为检测冲洗液吸收情况的标记物。     

Serum amino acids as indicators of cerebrospinal neuronal activity in patients with micturition disorders

OBJECTIVE: Our previous study showed that the spinal glycine level in rats was changed by spinal injury or bladder outlet obstruction, and this change was reflected by serum glycine levels. Therefore, we measured the serum glutamate and glycine levels in healthy volunteers and patients with cerebrospinal damage or benign prostatic hyperplasia (BPH) to confirm whether the change of serum amino acid levels was obtained from these patients as well as the animal experiment. METHODS: We measured the serum glutamate and glycine levels in 170 healthy controls, 57 patients with cerebrovascular disease (CVD), 68 patients with spinal cord injury (SCI), and 70 patients with BPH. Amino acid levels were compared between the controls and patients, according to gender, level of spinal injury and the type of bladder activity. RESULTS: In the healthy controls, glutamate levels were higher and glycine levels were lower in men than in women. On group comparison of each gender, there were no differences of glutamate levels. However, glycine levels were lower in male and female SCI patients and BPH patients than in controls. According to the level of spinal injury or the pattern of bladder activity and amino acid levels, there were no relationships among them. CONCLUSIONS: Serum glutamate and glycine levels were not related to the spinal injury level or bladder activity. However, serum glycine levels changed in patients with SCI or BPH patients, so it may be possible to use it as an indicator of spinal glycinergic neuronal activity.     

Role of seminal osmolarity in the reduction of human sperm motility

Mammalian sperm at ejaculation are suspended in the seminal plasma, a heterogeneous mixture deriving from the testicular/epididymal fluid and from secretions of seminal vesicles, prostate and bulbourethral glands. Biochemical characteristics of seminal fluid change along the male reproductive tract when considering its inorganic and organic composition and pH but it is known that in each region of the male genital tract seminal osmolarity is higher than that of serum. It has been previously demonstrated that in invertebrate and vertebrate sperm, seminal plasma osmolarity influences sperm motility and activity, and human sperm have been shown to possess osmosensitive calcium entry pathway that controls important functions such as acrosome reaction and oocyte penetration. In the present study, we have determined seminal plasma osmolarity in a large number of normozoospermic fertile and asthenozoospermic infertile subjects correlating it with sperm motility percentages and kinematic characteristics determined utilizing a computerized motion analysis system. Our results confirm that seminal plasma osmolarity is higher than that of serum (336.1 +/- 20.2 vs. 291.1 +/- 6.9 mOsm/L, respectively). Normozoospermic subjects show seminal osmolarity values that are significantly lower with respect to asthenozoospermic patients (317.8 +/- 12.2 vs. 345.2 +/- 22.6 mOsm/L, p<0.001), irrespective of the cause of asthenozoospermia. Seminal plasma osmolarity negatively correlates with sperm progressive motility percentages and kinetic characteristics (curvilinear velocity, linear velocity, linear coefficient and lateral displacements of sperm head). Furthermore, when sperm from fertile subjects were suspended in medium with an osmolarity increasing from 300 to 600 mOsm, sperm motility percentages and kinetics characteristics were progressively reduced and nearly abolished when medium osmolarity was 600 mOsm. On the contrary, when sperm from asthenozoospermic subjects with high semen osmolarity were resuspended in medium with lower osmolarity, sperm motility parameters improved significantly. Sperm motility parameters did not correlate with seminal plasma concentrations of sodium, potassium, chloride with a weak correlation only with seminal calcium concentration. No correlations are present between seminal plasma osmolarity and ionic composition.In conclusion, the present study confirms and extends the knowledge that, in human, seminal plasma osmolarity is higher than that of serum and demonstrates that seminal osmolarity influences sperm motility characteristics and then it may contribute to the pathogenesis of some forms of asthenozoospermia and male infertility.     

Plasma haemoglobin concentrations and other influx variables in blood in connection with transurethral resection of the prostate using distilled water as an irrigating fluid

Eight patients undergoing transurethral resection of the prostate (TURP) using sterile distilled water as an irrigating fluid were studied. The concentrations of plasma haemoglobin, serum sodium, serum prostatic acid phosphatase protein (PAP) and plasma osmolality were determined as possible indicators of absorption of irrigating fluid. In 3 patients there was a marked increase in plasma haemoglobin immediately postoperatively with a maximum of 3.3 g haemoglobin/l plasma. In the remaining 5 patients the plasma haemoglobin level did not exceed 0.7 g/l immediately postoperatively. In all cases there was a fairly rapid return of the elevated plasma haemoglobin level to preoperative values. There was also a postoperative increase in the serum PAP level which was not correlated with the simultaneous increase in plasma haemoglobin concentration. There was no significant change in the sodium, potassium or albumin concentration in serum nor in plasma osmolality postoperatively. There was some decrease in the postoperative serum creatinine and uric acid levels. The preoperative serum creatinine concentration was within reference limits in 7 patients and borderline high in 1 patient. The haemoglobin binding plasma protein haptoglobin showed a slight non-significant increase immediately postoperatively and a significant decrease in concentration 2 hours postoperatively. The mean plasma haemoglobin concentration immediately postoperatively did not exceed the mean preoperative haemoglobin binding capacity of serum. The mean preoperative haemoglobin binding capacity was 1.2 g/l and the mean plasma haemoglobin level was 1.2 g/l immediately postoperatively. Two hours later the mean plasma haemoglobin level was 0.8 g/l. The mean serum haptoglobin concentration was 2.4 g/l preoperatively, 2.6 g/l immediately postoperatively and 2.0 g/l 2 hours later.(ABSTRACT TRUNCATED AT 250 WORDS)