Holmium laser prostatic resection for patients presenting with acute urinary retention

Authors


Kevin T. McVary, Department of Urology, Northwestern University Feinberg School of Medicine, Tarry 16-749, 303 E. Chicago Ave, Chicago, IL 60611, USA.
e-mail: k-mcvary@northwestern.edu

Abstract

OBJECTIVE

To compare the outcomes of patients presenting with and without acute urinary retention (AUR) who were treated with 100-W holmium laser resection of the prostate (HoLRP), as laser therapies, including HoLRP, have been used for treating lower urinary tract symptoms secondary to benign prostatic hyperplasia (BPH), but the effectiveness of HoLRP for patients with AUR has not been fully elucidated.

PATIENTS AND METHODS

The medical records of 87 patients who had HoLRP were reviewed, and prospective questionnaires aimed at determining patients’ American Urologic Association Symptom Index (AUA-SI) and Quality-of-Life (QoL) scores and medication usage were also obtained. Statistical analyses were used to compare the clinical characteristics and outcomes between patients with and with no AUR for up to 2 years after HoLRP.

RESULTS

All patients had the catheter removed successfully by 1 month after surgery; those presenting with AUR tended to have a greater improvement in clinical outcomes than those with no AUR, including a mean AUA-SI score decrease by ≈13 and ≈8 points, and a QoL score decrease by ≈2 and ≈1.4 points, respectively. These decreases were maintained throughout the study period. Patients with AUR had significantly greater decreases in their postvoid residual urine volume than those with no AUR. Serum prostate-specific antigen levels also had a modest but sustained decrease (14%) in both groups. There were no significant decreases in the reported use of BPH-related medications after surgery in either group.

CONCLUSIONS

HoLRP (100 W) is a safe and effective surgical therapy for patients presenting with AUR. The present results suggest that the short- and long-term outcomes of these patients are similar between men presenting with and with no AUR.

Abbreviations
HoLRP

holmium laser resection of the prostate

AUR

acute urinary retention

SI

Symptom Index

PVR

postvoid residual urine volume

QoL

quality of life

Qmax

peak urinary flow rate.

INTRODUCTION

BPH is a common problem among older men, with an estimated histological prevalence of 70% of men in their 60s, and a prevalence of clinical symptoms secondary to BOO in half of men aged >50 years and >70% by 80 years old [1,2]. The associated LUTS cause significant morbidity among men with BPH and often drive them to seek treatment [3–5]. While these LUTS can significantly affect the quality of life (QoL) of a man, BOO can also lead to more severe sequelae, such as acute urinary retention (AUR), renal failure, bladder stones, haematuria, urinary incontinence, UTI, and bladder decompensation [6].

AUR is one of the most feared complications of BPH and is considered a urological emergency. Both AUR and moderate to severe LUTS can seriously compromise the QoL of affected men [7,8]. While the overall occurrence of AUR is decreasing secondary to medical therapies, it has been reported that AUR is the indication for 25–30% of men undergoing TURP [9,10]. While AUR is surgically treatable, operative morbidity and mortality are greater for patients who present in AUR than for those who undergo elective prostate surgery secondary to LUTS alone [11]. TURP has long been considered the reference standard surgical technique used for LUTS and AUR in men with moderately sized prostates, but has been associated with significant postoperative morbidity. Morbidity after TURP has been reported in up to 18% of men, and includes bleeding requiring a transfusion (0.4–7.1%) and TUR syndrome (0–1.1%) [10,12].

Several minimally invasive techniques have been subsequently developed to treat LUTS related to BPH, and are not associated with the morbidity of TURP. Overall, laser therapies have been associated with less morbidity than traditional TURP, including a shorter duration of catheterization, shorter hospital stay and less bleeding [13]. Because of its ablative and haemostatic abilities, and rapid immediate relief of symptoms, the Ho:YAG laser is an effective surgical tool that can be used cystoscopically to remove obstructing adenomatous tissue [13–15]. This method uses isotonic saline and therefore reduces the incidence of TUR syndrome. Furthermore, holmium laser resection of the prostate (HoLRP) is as effective as traditional TURP [16,17]. The use of a lower powered (80-W) HoLRP was previously suggested as effective in treating patients presenting with AUR secondary to BPH [18]; however, the outcomes of these patients, compared with those with BPH but not in AUR, remain unknown. The purpose of the present study was to compare the outcomes of patients both with and without AUR who were treated with high-powered (100-W) HoLRP.

PATIENTS AND METHODS

In all, 87 patients were treated with 100-W HoLRP between April 2005 and June 2007 by six different attending urologists at the Northwestern Memorial Hospital. The study was approved by the institutional review board and written informed consent was obtained from all 87 patients before HoLRP.

The surgical indications for HoLRP included moderate to severe LUTS (with or without AUR) and patient and surgeon preference. Patients were evaluated before surgery by a history and physical examination, and completed the AUA Symptom Index (SI) and QoL questionnaire forms, which they also completed at follow-up visits or by mailed questionnaires for up to 2 years after surgery. Serum PSA levels were measured before and at regular intervals up to 1 year after surgery. TRUS was used to assess prostate size, using the ellipsoid formula, and additional TRUS-guided biopsy was used to exclude prostate cancer, when appropriate. Patients with biopsy-confirmed prostate cancer were excluded from the study. When feasible, suprapubic ultrasonography was used to determine the postvoid residual urine volume (PVR). Furthermore, patient medical records, mailed questionnaires related to current health status, current medications and further medical and surgical treatments for BPH were recorded. Particular attention was paid to the use of medical therapy with α-blockers and 5α-reductase inhibitors before and after HoLRP. Some patients were assessed by urodynamic testing before HoLRP; the decision for urodynamic testing varied based on physician preference, and was often used to help distinguish obstructive and overactive components of the LUTS.

The HoLRP procedure was performed as previously described, under general endotracheal anaesthesia [19]. At our institution, the same 100-W holmium device (Lumenis, VersaPulse PowerSuite, Santa Clara, CA, USA) was used for all procedures. Similar to other reports, it is our practice to use the laser to remove wedges of prostate tissue for routine pathological analysis and confirmation of BPH, and it was reported that an effective histological diagnosis can be made from HoLRP surgical specimens [20]. Patients with incidentally discovered prostate cancer on histological analysis were excluded from the study.

All patients received antibiotic prophylaxis with ampicillin and gentamicin or a second-generation cephalosporin, and placed on 3–7 days of oral antibiotics on discharge. Depending on physician preference, patients were usually de-catheterized at 1–2 days after surgery and then given a spontaneous voiding trial. Patients who failed the voiding trial were re-catheterized and given an additional voiding trial, usually 3 days afterwards. If patients failed a second voiding trial, subsequent trials were at weekly intervals (for up to 1 month) or until patients were successful. 5α-reductase inhibitors decrease serum PSA levels [21], and therefore when indicated, PSA levels were corrected for the use of finasteride by doubling the value both before and after surgery.

When warranted, Student’s t-test with Bonferroni correction was used to compare values between groups.

RESULTS

Data were obtained from the 87 patients who had HoLRP; 31 of these men (36%) presented in AUR, while 56 (64%) were treated for moderate to severe LUTS alone. The mean (sd) patient age was 65.6 (10.9) years, and was not significantly different between the groups (Table 1); other baseline medical comorbidities are shown in Table 1.

Table 1.  The characteristics of the patients both with and with no AUR before, during and after HoLRP, and the changes in AUA-SI, QoL and PVR
VariableNo AURAURP
No. of men  56  31 
Comorbidities, n (%)
 Hypertension  13 (23)   6 (19) 
 Heart disease   9 (16)   4 (13) 
 Diabetes   6 (11)   2 (6) 
 Hyperlipidaemia   7 (13)   1 (3) 
 GERD   2 (4)   0 
 Vascular disease   3 (5)   2 (6) 
 Malignancy   1 (2)   8 (26) 
 CNS injury   3 (5)   2 (7) 
Mean (sd) {n} or n (%):
Age  66.0 (10.61) {56}  64.7 (11.56) {31}0.58
Prostate size, mL  51.4 (24.71) {33}  64.4 (28.63) {17}0.10
PSA level, ng/mL   2.14 (1.94) {53}   2.16 (2.01) {21}0.98
PSA (corrected)   2.65 (2.4) {53}   3.18 (3.86) {21}0.47
AUA-SI  20.7 (8.06) {44}  22.7 (8.41) {15}0.42
QoL   3.83 (1.19) {39}   4.14 (1.61) {14}0.43
PVR, mL 169.0 (163.0) {45} 570.8 (724.3) {25}<0.001
No. of BPH medications used   1.43 (0.66) {54}   1.52 (0.70) {27}0.60
N (%) on 5α-reductase inhibitor  21 (40) {53}   9 (41) {22}0.87
N (%) on α-antagonist  47 (87) {54}  24 (89) {27}0.98
Operative
 Total energy, kJ  111.2 (57.19) {37} 156.5 (66.45) {13}0.02
 No. of fibres   1.56 (0.78) {41}   2.18 (1.94) {27}0.07
 Operative duration, min   71.9 (36.8) {55}  98.6 (39.78) {30}0.003
 Hospital stay, nights    1.31 (0.76) {51}   1.62 (1.04) {13}0.25
 Change in haemoglobin, g/dL  +0.54 (0.77) {33}  +0.13 (1) {15}0.11
 Change in sodium, mmol/L  +0.42 (2.89) {27}  +0.88 (1.65) {17}0.46
Complications and medication use, n (%)
 Persistent LUTS  18 (32)   1 (3)0.001
 AUR   2 (4)   4 (13)0.10
 Retrograde ejaculation   1 (2)   00.46
 Incontinence   1 (2)   2 (7)0.26
 Urethral stricture   0   1 (3)0.18
 No. of BPH medications used   1.33 (0.72)   1.5 (0.66)0.25
Changes in AUA-SI, QoL and PVR at first visit
 AUA-SI  −8.02 (8.61) {38} −12.7 (10.20) {12}0.13
 QoL  −1.42 (1.62) {33}  −2.18 (2.18) {11}0.23
 PVR, mL−102.8 (125.0) {38}−475.4 (721.4) {21}0.003

Preoperatively, TRUS prostate volume, PSA values, AUA-SI and QoL scores were determined. There were no statistical differences in any of these preoperative parameters between groups (Table 1). We also analyzed the irritative (urgency, frequency, nocturia) and obstructive (hesitancy, weak stream, sensation of residual urine, straining) domains in the preoperative AUA-SI questionnaires independently without finding any significant differences between groups (data not shown). There were no statistical differences in the frequency of preoperative medical therapies for the treatment of LUTS/BPH between groups (Table 1). We did detect a significant difference (P = 0.0007) in preoperative PVR volumes in men who presented with AUR (570.8 ± 724.3 mL) compared with non-AUR patients (169.0 ± 163.0 mL; Table 1). It is important to note that the PVR values were obtained at a median time of 83 days preoperatively in the AUR group. When limited to patients who had values taken when able to void spontaneously (17/24), the men who developed AUR still had significantly higher preoperative PVRs when compared to the non-AUR group (254.8 mL vs. 169 mL; = 0.01).

The mean preoperative PSA value (uncorrected for 5α-reductase inhibitors) for all patients was 2.1 (1.9) ng/mL, and there were no significant differences between the groups (= 0.98). This trend was reinforced even after correcting for 5α-reductase inhibitor use (Table 1). As PSA level has been used as a proxy for prostate volume, it was not surprising that there was no significant difference in the TRUS-estimated prostate volume between the groups (Table 1) [22].

We analysed urodynamic variables before HoLRP (data not shown); no patient was in AUR at the time of urodynamic examination. Twenty-eight men (50%) subsequently categorized as not having AUR were tested ≥12 weeks before, compared to only nine men (29%) who were put in the AUR group. There were no significant differences between groups in any of the urodynamic variables. The volume at detrusor contraction in the no-AUR and AUR groups, respectively, were 318.6 (180.0) mL and 291.9 (187.0) mL (P = 0.72), and the maximum detrusor pressure on contraction was 93.6 (42.57) and 93.7 (39.63) cmH2O (P = 0.33), with no significant difference between groups. The maximum urinary flow rate (Qmax) in both groups was consistent with BOO, at 7.3 (5.6) and 8.2 (4.9) mL/s (P = 0.63) in the AUR and no-AUR groups, respectively. The volume at first sensation, first desire to urinate and strong urge to urinate were also not significantly different between the groups.

There were no complications during HoLRP in either group, although two patients in the no-AUR group required the use of a bipolar TURP to aid in resecting the apex. However, there were two significant differences between the groups (Table 1); men who presented in AUR had a higher total amount of energy used and the surgery took longer. There were no differences in estimated blood loss, change in sodium levels or length of hospital stay between the groups (Table 1).

The median duration of catheterization for the no-AUR group was 1 day, while it was ≈6 days in the AUR group (= 0.01). However, most (54%) patients in both groups had successful voiding trials on the first attempt, 72% by 3 days and ≈90% of patients were de-catheterized by 1 week. The complication rate after HoLRP was 13% (Table 1), not including a 22% prevalence of persistent LUTS typically seen in the no-AUR group. Notably, all four patients in the AUR group with recurrent AUR were not ambulatory and had significant medical illnesses, compared with the two patients in the no-AUR group with recurrent AUR.

Patients were assessed on each of their return visits with the AUA-SI questionnaire, and measurements of PSA level and PVR. Within each group, there were significant reductions in AUA-SI total score, QoL score, and PVR from before HoLRP to 4 months afterward. This improvement was maintained at all sample times up to 1 year (Figs 1,2), and in the 10 patients with available data at 2 years. Interestingly, there were no significant decreases in the reported use of medications (5α-reductase inhibitors or α-adrenergic antagonists) after surgery in either group up to 2 years after HolRP (Table 1). Indeed, most patients (≈55%) were maintained on dual therapy.

Figure 1.

AUA-SI trends before and at intervals after HoLRP in men with and with no AUR. There were no significant differences between groups at any interval. Values were significantly lower than before HoLRP at each interval, except at 6 months. *statistically significant.

Figure 2.

QoL trends before and at intervals after HoLRP in men with and with no AUR. The mean scores were significantly different between groups only at 1–2 years. Values were significantly lower than before HoLRP at each interval, except at 6 months. *statistically significant.

PSA levels were analysed at regular intervals after HoLRP (Fig. 3); the mean change in corrected PSA values for both groups was a modest 0.4 ng/mL (14%) decrease at 3 months. At presentation, the overall mean corrected PSA for both groups was 2.8 (2.9) ng/mL, which decreased to 2.4 (2.0) ng/mL by 3 months. This decrease was maintained throughout the follow-up, up to 1 year. There were no significant differences between the groups at any interval, as computed with a Bonferroni correction.

Figure 3.


The mean corrected PSA levels for both groups before and at intervals after HoLRP. There were no significant differences in mean combined PSA level before and after HoLRP at any interval.

The AUA-SI and QoL values were determined before and at 1, 4, 6, 12 and 24 months after HoLRP. The mean preoperative AUA-SI and QoL scores for both groups were 21.2 (8.1) and 3.91 (1.30), respectively, while the mean scores at 4 months were 11.4 (7.5) (46% decrease) and 2.27 (1.44) (42% decrease), respectively. Table 1 also lists the mean decreases in AUA-SI and QoL scores at the first follow-up visit (1–3 months). There were no significant differences between groups, but there were significant differences after HoLRP at several, but not all, sample times (Figs 1,2). When analysed at the sampling intervals, there was a trend for lower AUA-SI scores in men with AUR than in men with no AUR; this trend continued for up to 2 years (Fig. 1). Similarly, the QoL score for men with AUR was lower at every interval and only significantly lower at 1–2 years (Fig. 2). At the end of the study period, 63% of patients with an AUA-SI evaluation before and after HoLRP in the no-AUR group had a decrease of at least half in their AUA-SI scores, vs 92% in the AUR group.

The PVR was determined before and at 1, 4 and 6 months after HoLRP; there was a significant and sustained decrease in PVR in both groups (data not shown). The mean PVR was not significantly different between the groups after HoLRP and, as expected, the mean decrease was significantly greater in the AUR group (Table 1). At the 1- and 4-month assessment there were no significant differences in mean PVR between the groups and the mean PVR remained low (<40 mL).

DISCUSSION

The present results show that 100-W HoLRP is a successful treatment for LUTS related to BPH, and for patients presenting with AUR. Both groups had an immediate and sustained improvement in their AUA-SI, QoL scores and PVR. These results show a 45–48% improvement in AUA-SI and a 46–49% improvement in QoL by 4 months after HoLRP, which are slightly less than in previous reports [16,17,23]. We also report a 12.6% complication rate, which is consistent with previous studies [16,17,23]. The present results were also similar to those reported by Kabalin et al.[18], who described 80-W HoLRP in 36 men presenting with AUR. They reported decreased AUA-SI scores over the first 6 months (6.8, 6.5 and 5.7 at 1, 3 and 6 months) and no intraoperative complications. Similarly, other holmium laser-based therapies for treating BOO secondary to BPH were reported, e.g. holmium laser enucleation of the prostate (HoLEP). While HoLEP is a highly effective therapy and many proclaim this method as the new reference standard for laser prostate surgery, it has never been studied specifically in patients with AUR [24]. Furthermore, it is difficult to learn and requires considerable experience, and it has not been shown to be better than HoLRP [25].

The AUR group required significantly more laser energy and longer surgery for their prostate resection than the no-AUR group, despite having similar prostate volumes. Reasons for this might be related to increased surgeon attentiveness to complete resection, or subtle anatomical differences in patients with AUR, e.g. larger median lobes, longer prostates, or increased fibrotic tissue. The mean prostate volume before HoLRP (64.4 vs 51.39 mL, P = 0.10) and mean PSA levels (3.2 vs 2.6 ng/mL, = 0.47) for men in AUR was larger than in men with no AUR, which might have accounted for the increase in intraoperative variables, and might have been significant if more men with AUR had preoperative TRUS measurements.

The present data show that many patients with elevated PVR later presented in AUR. While this might be biased because some of the measurements were taken during the retentive episode, many PVRs (71%) were recorded several months before HoLRP, when the patients were able to void spontaneously. Although still controversial, these data support previously described notions that a high PVR predicts progression of BPH [26]. In the present patients the PVR was the only significant predictor of AUR, as the preoperative AUA-SI score, QoL score and TRUS volume would not have helped to identify those who would progress to AUR.

The AUA-SI scores and urodynamic testing data showed no quantitative differences between the groups. While we hypothesized that the no-AUR group would have more irritative baseline symptoms, while the AUR group would have more obstructive components, we were unable to detect statistically significant differences. However, there was a trend for lower AUA-SI and QoL scores after HoLRP amongst patients with AUR, suggesting they might have had a slightly better outcome secondary to the paucity of preoperative irritative symptoms. The lack of any differences could be related to the fact that most patients (22/31) who presented with AUR had no preoperative urodynamic testing, probably because of the acuteness of their disease. However, interestingly, many men (18/56) in the no-AUR group had persistent irritative voiding symptoms that were responsive to anticholinergics, vs only one of 31 in the AUR group. This is highly suggestive that men in the no-AUR group had more irritative baseline symptoms.

There was a 14% decline in the corrected mean PSA levels after HoLRP, which is less than previously reported [16]. As serum PSA levels approximate prostate volume, this probably reflects residual transitional zone tissue. However, all of the patients enrolled in the present study reported significant improvements in symptoms, and therefore we are confident that most BOO contributing to LUTS was resected. To date, there have been no further surgical treatments for BPH required by patients in either group. However, it remains a concern that the PSA levels after HoLRP might reflect a significant residual adenoma. In studies analysing open prostatectomy for treating BPH, PSA levels have been shown to reach a nadir soon after surgery and remain very low for up to 36 months, indicating nearly complete resection of the adenoma [27]. The presence of residual adenoma raises the question about the durability of the HoLRP procedure and whether patients treated are at risk of future symptomatic recurrence of their BPH.

When examining postoperative medication usage, there was no significant decrease in the use of either α-antagonists or 5α-reductase inhibitors in either group. There continued to be relatively many patients (≈80%) who continued to use at least one medication, which is probably related to residual adenoma (Table 1). Overall, almost all patients used these medications in the short term, and there was a decrease in the reported medication use in some in the long term. However, the exact duration of medication use was not always well documented, and prolonged use of BPH medications after surgery is not evidence-based.

There was a low rate of complications after HoLRP, the most frequent being a 7% rate of recurrent AUR and 3% stress urinary incontinence. However, there was a modest rate of sustained LUTS, as noted, which we attribute to the unmasking of preoperative irritative symptoms and not to a complication of the procedure. While there was a significantly longer duration of catheterization in the AUR group, importantly these patients often had more serious comorbidities, e.g. metastatic cancer (Table 1), that might have limited their mobility.

For many patients the primary goal of BPH management is a subjective improvement in LUTS; this is particularly true for patients who present with AUR. The present results show that 100-W HoLRP can be used in patients with or without AUR, and is associated with a significant and lasting decrease in LUTS, as shown by the AUA-SI and QoL scores, improved by 1 month and maintained throughout the follow-up. Taken together, our results suggest that HoLRP relieves LUTS secondary to BPH and can be effectively used in patients presenting with AUR.

In conclusion, 100-W HoLRP is effective for treating LUTS related to BPH in patients with or with no AUR. Its effects are immediate and sustained for up to 2 years. While HoLRP is associated with significant residual adenoma and does not eliminate the need for BPH medication after treatment, it significantly improves patients’ AUA-SI and QoL scores, and PVR. Detailed multicentre data involving a large population are needed to further address the long-term effectiveness of HoLRP in patients with AUR.

CONFLICT OF INTEREST

None declared.

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