Blood loss in transurethral prostatectomy: epidural versus general anaesthesia

[Anaesthesia and prostate surgery]

OBJECTIVES

To review the current data about anaesthetic management in prostate surgery with special regards on analysis and prevention of specific risks, appropriate anaesthetic procedure keeping with surgery and patient, recognition and treatment of adverse events.

DATA SOURCES AND EXTRACTION

The Pubmed database was searched for articles (1990-2004) combined with references analysis of major articles on the field.

DATA SYNTHESIS

It is strongly recommended to settle germfree urine in the preoperative period. The thromboembolic risk of radical retropubic prostatectomy for cancer parallels lower abdomen oncologic surgery and is prolonged. Preoperative evaluation of cardiovascular, respiratory, neurological and metabolic comorbidity is a source of prognostic information and an essential tool in the management of elderly patients with prostate disease. Extreme patient positioning applied in prostate surgery induces haemodynamic and respiratory changes and are associated with severe muscular and nervous injuries. The laparoscopic access for radical prostatectomy is a growing alternative to the open surgical procedure. Acute normovolaemic haemodilution is a consistent and cost-effective blood conservation strategy in reducing allogenic blood transfusion for radical retropubic prostatectomy. Whether open transvesical or transurethral prostatectomy for treatment of benign hypertrophy depends on the size of the gland: transurethral resection is safe up to 80 g. Intrathecal anaesthesia with a T9 cephalad spread of sensory block, produces adequate conditions for transurethral prostatectomy and allows a rapid diagnosis of irrigating fluid absorption syndrome. In spite of recommended preoperative antibiotic prophylaxis, bacteriemias are frequent during transurethral prostate resection.

[Modified technique for transurethral resection of the prostate with suprapubic drainage and local anesthesia]

PURPOSE

To establish a technique for transurethral resection of the prostate (TURP), combining the use of local anaesthesia with an Amplatz suprapubic tube, in patients at high surgical risk.

MATERIALS AND METHOD

A study was carried out in 32 patients who underwent TURP with a 30 F Amplatz suprapubic tube following local anaesthesia. This technique was indicated where surgery presented a general risk, in elderly patients, and for patients refusing to undergo spinal intradural or general anaesthesia. The mean age of the patients was 70 years (61-82 years). The risk of surgery was assessed according to the ASA classification.

RESULTS

According to the ASA classification, 7 patients were ASA III (21.9%), and 25 patients were ASA IV (78.1%). In 31 of the 32 patients the operation was completed in one session. When questioned about the pain they felt, 11 patients reported no pain, 12 slight discomfort and 3 occasional pain. In the latter three patients, intravenous sedation was enhanced with 0.1 mg etomidate per kg body weight. The volume of the resected fragments ranged from 18 to 120 ml, with a mean of 47 ml, except in one patient with 205 ml who required two treatment sessions.

CONCLUSIONS

Large prostate resection in patients at high surgical risk was performed comfortably using a combination of local anaesthesia and an Amplatz suprapubic tube. This procedure is one possible option to be considered as an alternative to other treatments.

Reduction of postoperative mortality and morbidity with epidural or spinal anaesthesia: results from overview of randomised trials

OBJECTIVES

To obtain reliable estimates of the effects of neuraxial blockade with epidural or spinal anaesthesia on postoperative morbidity and mortality.

DESIGN

Systematic review of all trials with randomisation to intraoperative neuraxial blockade or not.

STUDIES

141 trials including 9559 patients for which data were available before 1 January 1997. Trials were eligible irrespective of their primary aims, concomitant use of general anaesthesia, publication status, or language. Trials were identified by extensive search methods, and substantial amounts of data were obtained or confirmed by correspondence with trialists.

MAIN OUTCOME MEASURES

All cause mortality, deep vein thrombosis, pulmonary embolism, myocardial infarction, transfusion requirements, pneumonia, other infections, respiratory depression, and renal failure.

RESULTS

Overall mortality was reduced by about a third in patients allocated to neuraxial blockade (103 deaths/4871 patients versus 144/4688 patients, odds ratio=0.70, 95% confidence interval 0.54 to 0.90, P=0. 006). Neuraxial blockade reduced the odds of deep vein thrombosis by 44%, pulmonary embolism by 55%, transfusion requirements by 50%, pneumonia by 39%, and respiratory depression by 59% (all P<0.001). There were also reductions in myocardial infarction and renal failure. Although there was limited power to assess subgroup effects, the proportional reductions in mortality did not clearly differ by surgical group, type of blockade (epidural or spinal), or in those trials in which neuraxial blockade was combined with general anaesthesia compared with trials in which neuraxial blockade was used alone.

CONCLUSIONS

Neuraxial blockade reduces postoperative mortality and other serious complications. The size of some of these benefits remains uncertain, and further research is required to determine whether these effects are due solely to benefits of neuraxial blockade or partly to avoidance of general anaesthesia. Nevertheless, these findings support more widespread use of neuraxial blockade.

Transurethral resection of the prostate

Transuretheral resection of prostate (TURP) is a common operation in most hospitals. The patients are elderly and usually have concomitant diseases such as diabetes, hypertension, cardiac and respiratory ailments that increase their perioperative risk. Perioperative morbidity and mortality approaches 20% and 1% respectively. Regional anesthesia, notably spinal anesthesia, offers many advantages over general anesthesia for TURP with some evidence of lower morbidity even though similar mortality rates and overall outcomes are reported for both groups. Procedure-specific complications include TURP syndrome, bladder perforation, primary fibrinolysis, bacteremia, and septicemia. All are associated with significant morbidity and mortality but amenable to early and aggressive therapeutic intervention.

Total fluid balance during transurethral resection of the prostate

All fluids given and recovered during and for 24 hours following transurethral resections of the prostate (TURP) in 35 elderly men were recorded and compared with the health status of the patient. The results show that irrigating fluid absorption and the choice of a crystalloid or a colloid solution for intravenous fluid supplementation were the most important factors governing the total fluid balance at the end of TURP as well as 2 hours later. At 24 hours after the operation, the absorption of irrigating fluid during TURP and the presence of cardiac disease promoted retention of fluid. Impaired kidney function and serum cortisol concentration did not, however, correlate with the fluid balance.

Coagulopathies in patients after transurethral resection of the prostate: spinal versus general anesthesia

This prospective, randomized study evaluated the effects of spinal versus general anesthetic technique on perioperative blood loss and the development of postoperative coagulopathies in 50 patients undergoing transurethral resection of the prostate (TURP). Preoperative hematologic measurements included hemoglobin, platelet count, electrolytes, prothrombin time, partial thromboplastin time, fibrinogen, factor V, plasminogen, antithrombin III, and fibrinogen degradation product (FDP) levels. All hematologic blood samples wre repeated postoperatively at 1, 6, and 24 h. Intraoperative blood loss was not significantly different between the spinal and general anesthesia groups. The total blood loss after TURP was significantly correlated (r = 0.76; P < 0.0001) with the prostatic tissue weight. When the tissue weight resected exceeded 35 g, blood loss was in excess of the linear correlation shown with the weight of resected prostatic tissue. Platelet count decreased and prothrombin time increased in the spinal group at all postoperative time intervals compared to preoperative value (P < 0.05). There was no significant difference in measured coagulation variables (fibrinogen, factor V, plasminogen, antithrombin III, and FDP) between the spinal and general anesthesia groups, but there were significant decreases in postoperative fibrinogen and Factor V levels compared to preoperative values in both spinal and general anesthesia groups. Three patients (6%) had increased FDP levels 1 h postoperatively. The prostatic tissue weight and the surgical duration was significantly higher in these patients. We conclude that perioperative blood loss in TURP patients is not affected by the anesthetic technique. However, 6% of TURP patients developed subclinical intravascular coagulopathies which correlated with mass of resected prostate tissue.

Blood loss during transurethral resection of the prostate as measured by the HemoCue photometer

Blood loss was measured with the portable HemoCue photometer and the absorption of irrigating fluid was assessed by the ethanol method during 700 transurethral resections of the prostate. The blood loss ranged between 10 and 3,825 ml (median 300 ml). The weight of the resected prostatic tissue and the operating time were independent predictors of the amount of blood lost. General anaesthesia (n = 82) and malignant histology (n = 114) were associated with a smaller blood loss. In the patients who were given regional anaesthesia (n = 618), an mean systolic blood pressure of 100 mmHg or less resulted in a smaller bleed. Large-scale irrigating fluid absorption was typically associated with a blood loss of medium size and ranged between 500 and 1,000 ml. The incidence of such absorption was negligible in the patients in whom the blood loss per gram of resectate was less than 10 ml/g. Blood loss was also measured every 10 min during the course of another 110 operations, from which 20 patients with operating times in excess of 60 min were selected. Our analysis showed that no excessive blood loss occurred after 60 min of surgery.

Is planned continuous irrigation indicated for haemorrhage following transurethral resection of the prostate?

A prospective audit was carried out of this unit's policy of non-irrigation following transurethral prostatectomy (TURP). Over an 11-month period 121 TURPs were performed. Only 29 patients required intervention to maintain bladder drainage post-operatively, 23 of these requiring bladder washout alone. In the remaining 6 patients catheter change and continuous irrigation were required. The weight of tissue resected was the only factor investigated which bore a significant relationship to the necessity for further intervention in bladder drainage post-operatively. Despite this, patients requiring continuous irrigation post-operatively could not be easily identified prior to or during surgery.