Incidence and risk factors of bladder injuries during laparoscopic hysterectomy indicated for benign uterine pathologies: a 14.5 years experience in a continuous series of 1501 procedures
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Incidence and risk factors of bladder injuries during laparoscopic hysterectomy indicated for benign uterine pathologies: a 14.5 years experience in a continuous series of 1501 procedures
Marie-Christine Lafay Pillet 2
Franck Leonard 2
Nicolas Chopin 2
Jean-Marie Malaret 2
Bruno Borghese 0 1 2
Herve´ Foulot 2
Adolphe Fotso 2
Charles Chapron 0 1 2
0 INSERM, Unite ́ de Recherche U567 , Paris , France
1 Institut Cochin, Universite ́ Paris Descartes, CNRS (UMR 8104) , Paris , France
2 Universite ́ Paris Descartes, Faculte ́ de Me ́decine, Assistance Publique-Hoˆ pitaux de Paris (AP-HP), Groupe Hospitalier Universitaire (GHU) Ouest, Centre Hospitalier Universitaire (CHU) Cochin Saint Vincent de Paul, Service de Gyne ́cologie Obste ́trique II et Me ́decine de la Reproduction (Professor Chapron) , Paris , France
background: Laparoscopic hysterectomy is indicated as an alternative to laparotomy when the vaginal route is potentially difficult because of an immobile uterus and a poor vaginal accessibility. The aim of this study was to evaluate the rate, the risk factors for bladder injuries in a series of 1501 laparoscopic hysterectomies indicated for benign uterine pathologies. methods: This study was conducted retrospectively from January 1993 to 2000 and prospectively from 2001 to July 2007.The indications, patients' characteristics and complications were recorded. The overall rate of bladder injuries, the comparison of means (t test) and percentages (exact x2 test) between the cases and the population with no injury, the odd ratios (OR) and multivariate analysis were performed using the statistical package for the social sciences software. results: The rate of bladder injuries was 1% (15 patients). Risks factors were previous Caesarian section [OR: 4.33, 95% confidence interval (CI): 1.53 - 12.30] and previous laparotomy (OR: 4.69, 95% CI: 1.59 - 13.8). The rate of injury decreases with the surgeons' experience and reaches a plateau of 0.4% after 100 hysterectomies performed. conclusions: The rate of bladder injury during total laparoscopic hysterectomy is low and decreases with the surgeon's experience. Bladder injury is not linked to an increase of post-operative morbidity when recognized and repaired during the same laparoscopic procedure. The comparison with other routes of hysterectomies should take into account these risk factors.
total hysterectomy / operative laparoscopy / laparoscopic hysterectomy / complications / bladder injuries
Total hysterectomy for benign lesions is one of the more frequent
surgeries in women
(Merrill et al., 2008)
reported the first
case of total laparoscopic hysterectomy (TLH) in 1989. Laparoscopic
hysterectomy is indicated as an alternative to laparotomy when the
vaginal route is potentially difficult because of an immobile uterus or
a poor vaginal accessibility
(Chapron et al., 1995)
hysterectomies are done by laparotomy but the rate of hysterectomies
performed by laparoscopy is increasing regularly these last years
(Chapron et al., 1999; Farquhar and Steiner, 2002; David-Montefiore
et al., 2007; Istre et al., 2007)
. The benefit of laparoscopy compared
with laparotomy is actually well known
(Kovac, 2000; Garry et al.,
2004; Johnson et al., 2005; Falcone et al., 1999)
. Even if a meta-analysis
demonstrated that laparoscopy is not inherently dangerous
et al., 2002)
, one of the risks attributed to laparoscopic approach is
the increased risk of urologic complications
(Meikle et al., 1997;
Harkki-Siren et al., 1998; Garry et al., 2004; Johnson et al., 2005)
upon which bladder injuries are the most frequent (Makinen et al.,
2001). Incidence of bladder injuries is linked to anatomic
considerations as total hysterectomy needs vesico-uterin pouch dissection,
when a bladder injury may occur.
The aim of the study was to evaluate the rate of bladder injuries
during TLH on a large prospective monocentric observational study
and to analyse the risk factors of this complication.
Patients and Methods
All patients having a TLH performed between January 1993 and July
2007 for any pathology except cancer, genital prolapse and urinary
incontinence have been included in the study. All hysterectomies have
been performed according to a previously described procedure
(Chapron et al., 1994)
: the first step is the bipolar coagulation then
the section of adnexal pedicules followed by the dissection of the
uterovesical pouch, the bipolar coagulation of uterine pedicules, the
coagulation of the cervico-vaginal vessels, the bipolar coagulation then
section of utero-sacral ligaments. Then the last step is the opening of
the vagina on the anterior circumference and once the peritoneum
had dropped, the patient is placed in the gynecologic position, the
vaginal incision is terminated and the uterus extracted. The main
characteristics of hysterectomy were as follows: (i) in all cases hysterectomy
was total (subtotal hysterectomies were excluded) indicated for a
benign pathology; (ii) hemostasis was performed using bipolar
coagulation and (iii) all procedures were done using conventional disposable
instruments (Karl Storz Endoskope, Tutlingen, Germany).
During the study period, medical, operative and pathological reports
were collected for each patient. Between January 1993 and December
2000, data were collected retrospectively (711 cases). Since January
2001 to July 2007, the same data collection was performed prospectively
(790 cases). For each patient the following criteria were analysed and
collected into a data base
(Leonard et al., 2007)
: (i) patients’ characteristics:
age, height, weight, BMI, gravidity, parity, menopausal status, pre-operative
transvaginal ultrasonographic uterus measures, indication for total
hysterectomy, previous history of vaginal delivery, Cesarean section (CS) and
adhesiogenous abdomino-pelvic surgery
(Leonard et al., 2005)
operative and post-operative results: operative time, hospital stay, uterine
weight, associated surgical procedures (adhesiolysis, uterine
morcellation, adnexectomy and endometriosis), conversion, complications,
re-hospitalization and (iii)bladder injuries: cases, diagnosis modality,
treatment modalities and sequels.
The comparison of prospective and retrospective data showed no
significant statistical differences for the general characteristics of the two
populations (age, parity, menopausal status, uterine weight, etc.) except a
higher BMI in the prospective part (Table I). Despite an expected
nonsignificant underestimation of some parameters in the retrospective data
and under-reporting of some minor post-operative complications
compared with the prospective data (Table II), they did not affect the
significant variables, so data were pooled and analysed together.
The overall rate of bladder injuries was computed. The means of the
two populations with and with no bladder injury have been compared
using t test and analysis of variance and percentages using exact x2 test
or Fisher’s exact test when the assumptions for x2 distribution were
violated. The Kruskall – Wallis test was used to compare several groups of
non-parametrical data; for predictive variables the odd ratios (OR) were
calculated. A P-value of less than 0.05 was considered as statistically
significant. A discriminant analysis was used when applicable with a stepwise
technique introducing significant variables to identify those contributing
to the model. All the statistics were done using the statistical package
for the social sciences statistical analysis program system [SPSS for
windows release 14.0.1 (7 December 2005) Chicago SPSS Inc.].
During the study period, 1501 patients underwent a laparoscopic
Patients’ characteristics and indications for surgery are detailed in
Table I for the total population, the retrospective and prospective part.
The rate of bladder injuries was 1% (15 cases).
The pre-operative patients’ characteristics according to the existence
or non-existence of a bladder injury are reported in Table III. There was
no association with menopausal status, BMI, gravidity, parity, uterus size,
uterus weight and patients with bladder injuries were statistically
younger (44 + 2.8 versus 48 + 6.8 years). The pre-operative factors
significantly associated with bladder injury are the following: previous
laparotomy [446 (30%) versus 10 patients (67%); OR: 4.69, 95%
confidence interval (CI): 1.59 – 13.8]; previous adhesiogenous
abdominopelvic surgery [375 (25%) versus 8 patients (53%); OR: 3.4, 95% CI:
1.23– 9.45]; previous CS [199 (13%) versus 6 patients (40%); OR:
4.33, 95% CI: 1.53– 12.30); mean number of previous CS (0.19 +
0.55 versus 0.73 + 1, P , 0.0001) and no previous vaginal delivery
[550 (37%) versus 10 patients (67%); OR: 3.43, 95% CI: 1.16 – 10].
The discriminant analysis with step-by-step introduction of the
significant variables shows that previous CS is the most important factor
influencing the onset of a bladder injury followed by previous laparotomy.
No previous vaginal delivery and previous adhesiogenous
abdominopelvic surgery did not contribute significantly to the model.
For patients who had one CS, the percentage of bladder injuries is
1.4%, and for those who had more than one is 7%. The
nonparametric Kruskall – Wallis test comparing the incidence of bladder
injury between groups of patients having one, two or three or more
CS is statistically significant (P , 0.001) indicating that the risk
increases with the number of previous CS.
Per and post-operative patient’s characteristics according to the
occurrence or not of bladder injury are reported in Table IV: in case of bladder
injury, the mean time in the operating room is 78 min longer [131 + 44
(35 – 350) versus 209 + 84 (90 – 420), P , 0.003] and the mean length
of uncomplicated surgery is 124 + 39 min (range 35 – 350). The rate of
laparo conversion is significantly higher as three laparotomies have been
done to repair bladder injuries. The diagnosis of bladder injury is done
peroperatively in all cases; no bladder injury was unknown at the time of
surgery. Another surgical-associated procedure such as adnexectomy,
adhesiolysis, myomectomy or endometriosis does not increase the risk.
The length of hospital stay increased significantly from a mean of 3.5 +
1 to 5.7 + 2 days. There was no increase of urinary infection, and no
significant decrease in hemoglobin level. There was one hematoma, one
fever above 388C, one vesico-vaginal fistula, which needed a bladder
catheter for 1 month.
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P .. N 0 N 0 N N N N N 0 N 0 0 N
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Among the 15 patients with a bladder injury, 11 patients had at least
two risks factors, 2 had at least one risk factor and 2 had none but
were operated by a junior surgeon and had an oversized uterus. All
bladder injuries were diagnosed during surgery and only three were
treated by laparotomy at the beginning of the surgeons’ experience.
Neither severe post-operative complications nor sequels were
noticed after management of bladder injuries.
We looked at the learning curve concerning bladder injury: 19
surgeons participated in the study, 7 have done more than 30
procedures, 4 more than 50, 3 more than 100 and 2 more than 200.
The rate of bladder injures was 1.9% during the first 40 procedures
of all surgeons, 1.5% on the following 60 procedures and 0.4% after
100 procedures performed showing a decrease of the percentage of
bladder injuries as the number of hysterectomies performed by each
surgeon increases (Fig. 1).
The rate of bladder injuries on the series of 1501 TLH is 1%. These
results are in agreement with those of most other series (Table V).
Some authors claimed that urinary tract injuries, especially bladder
injuries, appear to be more frequent by laparoscopy
et al., 1998; Makinen et al., 2001)
. Johnson published a meta-analysis
of prospective randomized trials including 16 trials comparing abdominal
and laparoscopic routes, 4 comparing vaginal and laparoscopic routes, 1
laparoscopic-assisted vaginal hysterectomy with TLH, 1 laparoscopic
with vaginal and abdominal and 3 comparing the three routes of
hysterectomies. The rate of urinary complications looks higher with
laparoscopy even if the difference in rate of bladder and ureter injuries alone
was not statistically significant (Johnson et al., 2005). Garry et al.
Figure 1 Cumulative number and percentage of bladder injuries
according to the total number of hysterectomies per surgeon.
(2004) in a randomized prospective trial compared in one arm the
vaginal and the laparoscopic routes and in the other arm laparotomy
and laparoscopy excluding the learning phase (more than 25
procedures) and large uteri (more than 12 weeks’ gestation size). He
found 1% rate of bladder injuries for laparotomy compared with 2.1%
for laparoscopy and in the second arm a 1.2% rate for vaginal route
compared with 0.9% for laparoscopy, but he noticed that in the first arm
there were significantly more nulliparous, past history of CS and
endometriosis and unfortunately the number of hysterectomies in the
second arm was too small to conclude
(Garry et al., 2004)
However, the comparison of complication rate between the
different routes of hysterectomy needs to take into account the bladder
injury risk factors. The incidence of risks factors is not regularly
distributed in the different routes of surgery. Previous laparotomies and
previous deliveries by CS influence the surgeon’s choice for the route of
hysterectomy: this is a bias of selection which can obviously influences
the results. In particular, this could explain why there are more risk
factors for the laparoscopic approach than for the vaginal route.
In our series the main risk factors are previous CS and previous
laparotomy. No previous vaginal delivery and adhesiogenous surgery
can also increase the risk if associated.
Risk factor, such as previous CS, has already been shown for the
(Mathevet et al., 2001; Boukerrou et al., 2004)
laparotomy (Carley et al., 2002). Pelvic adhesions (OR of 1.7) and previous
CS (OR of 1.9) have been shown to be significant risk factors for
bladder injury during hysterectomy when the route of hysterectomy
have been considered as feasible by vaginal, abdominal or laparoscopic
(Davies et al., 2002)
Rooney et al. (2005)
analysed 51 bladder
injuries in a case – control study where each case was matched for age,
type of hysterectomy, adhesiolysis, prolapse surgery, incontinence
surgery, adhesiolysis to three patients having hysterectomy and no
bladder injury: the cystostomy OR for CS was 2.04 (95% CI: 1.2 –
3.5). All these results show that risk factors exist independently of
the route of hysterectomies, but in most series they are not equally
distributed in the three modes of hysterectomies. The comparison
is then impossible unless the risk factors are previously controlled.
We show in our series that the incidence of bladder injury decreases
with the surgeon’s experience. The analysis of a large retrospective data
(Wattiez et al., 2002)
shows that the rate of bladder injury
decreases from 2.3% on the first 952 cases to 0.9% on the following
695 cases. Also, a large prospective study of 10 110 hysterectomies
in 1996 in Norway gives a higher percentage of bladder injuries for
laparoscopic hysterectomies, which reaches 1.3%, but decreases from
2% for the first 30 procedures to 0.8% after the first 30 procedures
(Makinen et al., 2001)
. These results are in agreement with our rate
of almost 2% in the first 40 procedures of all surgeons and the rate
of 0.4% for the hysterectomies performed after 100 cases of the
surgeons’ experience. This could also explain why data including the
learning phase of surgeons show a higher incidence than the more classical
approaches, and these rates should decrease with the experience of
the surgeons. Data on 929 TLH show a decrease in overall
complications from 4% in the first 40 cases to 0.5% in the next 30 cases
(Altgassen et al., 2004)
Kreiker et al. (2004)
show that the duration
of surgery decreases significantly after 80 procedures. In Table V, one
can see that most reports of large cohorts of procedures performed
between 1989 and 2000 give a rate of injuries above 1.5% as more
recent cohorts after 2000 show a rate of less than 1%; this rate is
similar and sometimes lower than vaginal and abdominal hysterectomies
(Vakili et al., 2005; David-Montefiore et al., 2007; Garry et al., 2004)
is too early to conclude that the laparoscopic approach could decrease
the rate of this specific complication, but this is a reasonable hypothesis
which could be validated soon. We can already conclude that the rate
of bladder injuries when the learning curve is excluded and when the
risk factors are controlled does not look higher for TLH.
The diagnosis of bladder injury in our cases has always been made
during the procedure. It is important that the diagnosis should be done
per-operatively to avoid re-intervention and re-admission, which
increase the cost and the morbidity. Cases of unknown complications
at the time of surgery have been reported as high as 42%
et al., 1998)
(Ostrzenski and Ostrzenska, 1998)
Vakili et al.
gives a rate of only 35% of diagnosis before cystoscopy done
systematically at the end of the procedure and conclude that it
should be performed more widely. A review of articles found that
the rate of bladder injuries reported after hysterectomies is higher if
a cystoscopy is systematically performed at the end of surgery
(Gilmour et al., 2006)
To prevent bladder injures we perform a very careful dissection of
the vesico-vaginal pouch and use a simple uterine canulation; we don
not use, as other teams do, a specific uterine manipulator
et al., 2002)
. Uterine canulation associated with a vaginal packing of
the anterior cul de sac allows the assistant pushing the uterus in the
direction of the promontory to facilitate the dissection between the
anterior wall of the vagina and the bladder. In case of difficult
dissection, such as previous surgery (CS, endometriosis, conization, etc.), it
is possible to visualize the limits of the bladder by filling it through the
catheter with a methylene blue dye solution. This should be done
systematically at the end of the procedure to avoid unknown injury.
Hemostasis by bipolar coagulation in the vesico-vaginal space should
be done carefully. Some bladder injuries have been described when
introducing trocards, the safety rules of introduction have to be
followed, in particular avoiding the Pfannenstiel scar in case of previous
Vaginal hysterectomy is still a first choice for most surgeons and we
do not discuss that point here. This study is not a comparison with the
vaginal route but the data show that we have to re-evaluate the
laparoscopic technique as our experience increases especially for
parameters like operative time, urinary tract complications and the
decreasing percentage of hysterectomies done by laprotomy so that
the comparison with vaginal route could be more accurate.
The strength of present study lies in the large number of unselected
cases with the same technique used by all surgeons. Further large
prospective studies are necessary to confirm the risk factors and achieve
the comparison with other routes of hysterectomy.
The rate of bladder injuries is low and decreases with the surgeon’s
experience. This complication has a low morbidity especially if the
diagnosis is performed at the time of surgery and the bladder
repaired laparoscopically. Better knowledge of risk factors as we
showed in this study, in particular previous CS and previous
laparotomy, can avoid some bladder injuries as the surgeon is more careful
in the dissection of the vesico-vaginal pouch and performs a blue
methylene dye instillation test for diagnosis and repair of the injury
during the surgical procedure. These risk factors are shared with
all types of hysterectomies. When risks factors are controlled the
rate of bladder injury during TLH is not increased. Urologic
complications, which have been considered by many authors as more
frequent in TLH, have to be re-evaluated on the basis of new
prospective studies taking into account the learning curve and the
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Submitted on June 30 , 2008 ; resubmitted on November 15, 2008 ; accepted on November 24, 2008