February 2006, Vol 28, No. 2
Update Articles

Hysterectomy revisited

Eric T C Lee 李達財

HK Pract 2006;28:86-93

Summary

As gynaecology develops and grows, so does the range of operative techniques for hysterectomy. The continuing improvement of care to patients has been reflected by better surgical outcome and increase in patient satisfaction. Hysterectomy is the treatment of choice for certain gynaecological conditions. It has traditionally been performed using either the abdominal or the vaginal approach. Laparoscopic hysterectomy, a new approach with all its variants, has recently been developed as a worthy alternative. Media publicity, public awareness, and patient preference for minimally invasive surgery have increased the demand for laparoscopic hysterectomy. In the era of evidence based medicine, family doctors should be confident in discussing the indications and various available approaches for hysterectomy with patients before making appropriate referrals to specialists for further management.

摘要

隨著科技的進步,子宮切除術的技術亦在不斷發展。在醫療成果上的改善可見於更好的外科手術成效和病人的滿意程度。子宮切除術是治療多種婦科病的一種選擇。傳統上須由腹部或陰道進行,但經腹腔鏡子宮切除術近來已被確定為另一種有用的手術方式。傳媒的廣泛報導,公眾的關注,以及病人對微創外科手術的認同,己經增加了對腹腔鏡子宮切除術的需求。在以實證醫學為基礎的時代,當作出合適的專科轉介之前,家庭醫生應有充分準備和信心跟病人討論子宮切除術的適應症和各種手術方法。


Introduction

The origins of vaginal and abdominal hysterectomy can be traced to the 19th century. In the first half of the 20th century, subtotal abdominal hysterectomy was the norm but by the 1950's it was replaced by total abdominal hysterectomy. The stated reason for this shift was to lower the death rate from cervical cancer. Nowadays, most hysterectomy operations are performed through the conventional abdominal approach. In the UK, 88% of all hysterectomies were performed abdominally before 1992;1 whereas in the USA, over two-thirds of all hysterectomies were performed by laparotomy.2 Only a small proportion of hysterectomies were performed vaginally around that time.3 Dr H Reich reported the first case of laparoscopic hysterectomy (LH) in 1989.4 Initially, there were numerous publications proclaiming a place for LH in the surgical repertoire of gynaecologists. However, the enthusiasm for this technique was not shared by most gynaecologists. This is caused by factors such as prolonged operative time, higher equipment and consumable costs, slow learning curve and concerns about medico-legal issues.

In Hong Kong, the development of LH followed a similar pattern as that in the West. LH was first introduced locally in 1993. The first Territory-wide audit on endoscopic gynaecological surgery was conducted in 1997 and it reported a total of 209 cases of LH5 [96% of these cases were in fact documented as laparoscopic assisted vaginal hysterectomy (LAVH)]. Two years later, the 1999 Territory-wide O&G audit reported a total of 287 cases of LH,6 which represented only 5% of all hysterectomies performed for benign gynaecological conditions in 1999. The evidence showed a slow deployment of LH by local gynaecologists at the time, as reflected by the modest increase of only 78 cases of LH in the two-year interval. However, the momentum clearly shifted subsequently as shown in the 2002 Territory-wide audit on endoscopic gynaecological surgery.7 It reported an almost 2-fold increase (492 Vs 287) in the number of LH compared with that in 1999. By 2002, a study reported 13% of hysterectomies for benign gynaecological conditions were performed laparoscopically in the public sector.8 The results of the above audits indicated that the number of LH was rising and that LH was becoming more widely accepted. Indeed, in the past 10 years, there have been great advances in minimally invasive surgical techniques coupled with increase interests in laparoscopic approach to hysterectomy. The trend leads one to anticipate further rise in the use of laparoscopic access in performing hysterectomy.

The notion of sustaining just minor trauma for major surgery as provided by minimally invasive procedure such as LH and vaginal hysterectomy (VH) is a popular one. Today, with the improvement in surgical techniques associated with better instrumentation, doctors can now offer an additional method of care which has been shown to give better patient satisfaction and surgical outcome.9 With LH, post-operative pain is less. Shorter hospital stay is also possible with improvement in process and logistics for "day case surgery"10 and the end-result is that surgery is less stressful and anxiety level is lowered .11

Indications

Clinical guidelines and indications for hysterectomy were laid by the Society of Obstetricians and Gynaecologists of Canada in 2002.12

Recommendations
1) Benign diseases
  a) Leiomyomas: For symptomatic fibroids, hysterectomy provides a permanent solution to menorrhagia and the pressure symptoms related to an enlarged uterus.
  b) Abnormal uterine bleeding: Endometrial lesions must be excluded and medical alternatives should be considered as a first line of therapy.
  c) Endometriosis: Hysterectomy is often indicated in the presence of severe symptoms after other treatments have failed and when fertility is no longer desired.
  d) Pelvic relaxation: A surgical solution usually involves vaginal hysterectomy, which must include pelvic supporting procedures.
  e) Pelvic pain: A multidisciplinary approach is recommended as there is little evidence that hysterectomy will cure chronic pelvic pain. When the pain is confined to dysmenorrhoea or associated with significant pelvic disease, hysterectomy may offer relief.
2) Pre-invasive disease
  a) Hysterectomy is usually indicated for endometrial hyperplasia with atypia.
  b) Cervical intraepithelial neoplasia in itself is not an indication for hysterectomy.
  c) Simple hysterectomy is an option for the treatment of adenocarcinoma-in-situ of the cervix when invasive disease has been excluded.
3) Invasive disease
  Hysterectomy is an accepted treatment or staging procedure for endometrial carcinoma. It may play a role in the staging or treatment of cervical, epithelial ovarian and fallopian tube carcinoma.
4) Acute conditions
  a) Hysterectomy is indicated for intractable postpartum haemorrhage when conservative therapy has failed to control bleeding.
  b) Tubo-ovarian abscesses that have ruptured or do not respond to antibiotics may be treated with hysterectomy and bilateral salpingo-oophorectomy in selected cases.
  c) Hysterectomy may be required for cases of acute menorrhagia refractory to medical or conservative surgical treatment.

Controversies

There have been many debates on which is the best method of performing a hysterectomy. Many studies have been conducted to compare the outcomes of different approaches to hysterectomy as well as the variations in LH techniques. It is very difficult to conclude which LH surgical technique is superior. Any conclusion based on assessing a number of different procedures with their varying degree of complexity and performed by different surgeons with diverse levels of skills and experience for a variety of indications in a study with complex case-mix can be misleading. Future good studies should delineate the exact amount of dissection during each phase of the procedure to compare outcomes and to provide information that will enable detection of faulty techniques. Furthermore, the challenge to accumulate data, critically analyse each technique and select the most appropriate procedure for any individual patient holds the greatest promise for patient satisfaction and favourable outcome.

Classification
 
1) Abdominal approach
  Abdominal hysterectomy is more commonly used as compared to other approaches.13 The mortality risk related to hysterectomy has been best studied in USA by several authors, and has been found to be significantly higher in the abdominal group. Excluding pregnancy and cancer related cases, the mortality rate for abdominal hysterectomy was 8.6 per 10,000 women having hysterectomy.14 Abdominal hysterectomy necessitates laparotomy which usually is associated with increase in blood loss, increase in post-operative pain and ileus, increase in thromboembolic complications, prolonged hospital stay, delay in recovery, delay in returning to work and normal activities, wound complications like infection, abscess formation, haematoma, dehiscence, hernia formation, poor cosmesis, increase in abdominal adhesion and tissue trauma. The average convalescence period after abdominal hysterectomy is around 6 weeks. Hospital expenses for abdominal hysterectomy are somewhat similar to those using other approaches but the longer hospitalisation and convalescence period can result in considerable increase in direct and indirect costs. In general, a minimally invasive procedure should be preferred if it can be accomplished safely. The abdominal approach should not be disregarded nevertheless, as it can be useful in special situations.
2) Vaginal approach
  a) Vaginal hysterectomy
   

Throughout much of the nineties, the rate of VH remains pretty much unchanged. In the USA in 1990, 24.4% of American women having hysterectomy had a vaginal procedure, while in 1997 it was 23.3%.13 In the last few years, there appeared to be a renaissance of the vaginal approach despite emergence of arguments against this approach.15,16

The anecdotal argument often goes like this:-

  1. vaginal hysterectomy is technically more difficult and hence best avoided,
  2. hysterectomy can be more easily performed via a wide, open abdominal incision,
  3. lack of training in vaginal surgery and uterine morcellation techniques,
  4. absence of clear guidelines for appropriate patient selection,
  5. incompatibility with physician practice style and habits,
  6. lack of patient knowledge about surgical options,
  7. inappropriate decision making.
    Yet there are advantages to VH. It can be performed more quickly at lower cost and avoids the necessity of an abdominal incision. The absence of abdominal incision helps to reduce the depth and the length of anaesthesia and therefore the procedure is better tolerated by elderly patients and those with complicating medical conditions. Without the inevitable incisions for the insertion of laparoscopic trocars, trocar related complications will not happen. VH is almost entirely performed extraperitoneally with minimal manipulation of the intestines and hence less chance of post-operative ileus. Patients are able to ambulate earlier and hence can be discharged from the hospital sooner. The average convalescence period after vaginal hysterectomy is around 3 weeks. Combining shorter hospitalisation, convalescence and operative times, VH is undoubtedly the least costly intervention. Patients also appreciate having no surgical scar for both aesthetic and functional reasons.
    There are, however, relative contraindications to VH.17 These include decreased accessibility and mobility of the uterus and the adnexa, uterine size of more than 12 weeks (approximately 280 grams), pelvic adhesions as a result of previous pelvic surgery, endometriosis and chronic pelvic inflammatory disease, requirement for the removal of ovary and nulliparity. Some surgeons experienced in vaginal surgery can claim a success rate, even without case selection, of more than 90% for cases requiring hysterectomy using the vaginal approach alone.18,19 They advocate trial VH even in the presence of the relative contraindications, by first performing examination under general anaesthesia with or without laparoscopic assessment and then proceeding to VH as necessary.20 For cases with relative contraindications, the clinical examination which is carried out after induction of anaesthesia just before the start of the operation will help one to appreciate the degree of uterine mobility or "relaxation", the extent of descent of the uterus as assessed by traction on the cervix, and the uterine volume as compared with the vaginal access. As a rule, a uterus without surrounding pathology would descend when traction is applied under anaesthesia even in a nulliparous woman. The size of the uterus that can be removed vaginally increases with the experience of the surgeon who may use a variety of techniques such as enucleation of fibroids, bisection, morcellation and coring. Full explanations should of course be given to the patient and she should be informed of a possible change in the surgical route depending on intra-operative findings.
    VH can be regarded as a "blind" procedure. The uterus is removed from the pelvis without the opportunity to determine if there are any lesions such as endometriosis or adhesions, nor their correction. Without a chance to re-inspect the pelvis following hysterectomy, VH can be associated with post-operative complications related to vault bleeding and results in post-operative interventions, increased rate of blood transfusion, ultrasound evidence of post-surgical haematoma and febrile morbidity.16,21-23
  b) Painless hysterectomy
    "Painless hysterectomy" has been used to describe a new technique to VH using bicoagulation forceps. The newly developed BiClamp bicoagulation forceps (Erbe, Tubingen, Germany), using technologies originally developed for endoscopy, is specially designed for vaginal surgery and corresponds to the traditional Heaney forceps. The forceps are non-locking and in order to avoid irregular currents and accidental thermal injuries, they are covered with insulation material except for the areas specifically designed for coagulation. The electrical current passed is regulated and bipolar, and is automatically controlled by the attached VIO-Erbe electrosurgical system. The BiClamp forceps serves to provide an almost perfect haemostatic surgery by achieving good haemostasis with regard to the lateral pelvic sidewall, but also to avoid retrograde bleeding from the uterus. The term "painless" is associated with this technique because there is objective evidence of less post-operative pain compared with conventional VH.24 It is believed that coagulation destroys pain-sensitive nerve fibres as opposed to these being snared in sutured pedicles where tension and stretching lead to an increased pain sensation felt by the patient. There is also minimal devitalised tissue produced and thus reducing in the amount of inflammatory reaction.
3) Laparoscopic approach
  a) Laparoscopic hysterectomy
    The origin of laparoscopic hysterectomy (LH) has its root in "laparoscopy facilitated VH". That is to say laparoscopy was meant to convert what would have been an abdominal hysterectomy into a VH and a difficult VH into a safer and easier one. The goal of all minimally invasive procedures, including LH should be to accomplish a surgical task in an efficient manner while lowering the morbidity and mortality for the patient. With the development and progress of minimally invasive surgery, there has been an increase in number of methods available for performing LH. Various combinations of laparoscopic and vaginal techniques have been devised. However, there is, as yet no general agreement on the best method for performing a LH.
    A classification of the various types of LH can be made on the basis of the amount of surgery performed by the laparoscopic route.25 If every step of the procedure is performed laparoscopically, the operation is termed total laparoscopic hysterectomy (TLH). This operation is the laparoscopic analogy of total abdominal hysterectomy. If all the major vascular pedicles including the uterine vessels are secured by laparoscopic techniques but the vaginal vault and supporting ligaments are secured vaginally, the procedure is called a laparoscopic hysterectomy (LHa). When only the adnexa and upper uterine pedicles with or without the bladder flap are dealt with laparoscopically, the procedure is termed a laparoscopically assisted vaginal hysterectomy (LAVH). It is noted that the operative time of the surgery increases as the extent of the surgery performed laparoscopically increases, particularly when the uterine arteries are divided laparoscopically and laparoscopic approaches require greater surgical expertise.26 However, laparoscopic division of uterine arteries as performed in TLH and LHa is associated with reduced blood loss compared with LAVH.27 TLH and LHa can be difficult with an enlarged uterus as it reduces the operative field, diminishes accessibility which in turn may increase surgical difficulties and complications. In the presence of a large uterus, it is easier to ligate the uterine vessels vaginally as in LAVH.
    LH is associated with small incisions and less scarring, less blood loss, less post-operative pain, shorter hospital stay, faster recovery with an earlier return to work and full activity with its remarkable economic savings, fewer post-operative adhesion formation and less tissue trauma.26,28 LH allows for better visualisation of the pelvic pathology through magnification with targeted lighting. LH also allows for different viewing angles through uterine manipulation. Not all of these LH advantages are available to the abdominal or vaginal approach. Furthermore, it enables surgeons to accomplish immediate and precise haemostasis and to operate with accuracy and less devitalised tissue.
    The perceived disadvantages of LH are increase in operating time, increase in operative cost, the longer time-scale required to develop proficiency and increase in the risk of urinary tract injury.26,29
  b) Laparoscopic supracervical hysterectomy
    Laparoscopic supracervical hysterectomy (LSH) in which the cervix is left behind can be the procedure of choice for some surgeons. Its most positive attributes include decreased overall morbidity, applicability to uterus of virtually any size, probable improvement of overall pelvic floor support secondary to the intact pericervical ring and preservation of the neurovascular supply to the vagina and bladder. Furthermore the possibility of maintaining the procedure as a totally laparoscopic procedure offered a potential simplification to the average operation. LSH seems to be a procedure that is suitable to most benign lesions and it does not require the surgeon to be an advanced vaginal surgeon or an advanced laparoscopist. There are however, relative contraindications for the procedure. These include significant pelvic floor laxity and any patient who cannot be relied upon to continue with cervical cytologic surveillance.30 The risk of cervical disease following LSH is no greater than in patients with intact uterus but patients should be counselled to continue with periodic PAP smears. The discussion prior to surgery should include an explanation of not only the potential benefits of retention of the cervix but also the potential liabilities of keeping the cervix intact.
    A different type of supracervical hysterectomy called Classic Intrafascial Semm Hysterectomy (CISH)31 has also been in use efficiently while sparing the need for an extensive vaginal procedure. The CISH procedure has some integral differences from LSH. It includes the complete coring of the whole cervical canal as part of the whole procedure, resulting in fusion of the rest of the cervix and the extirpation of the endocervical epithelium together with the cervical transformation zone, thus minimizing the chance of cervical cancer and future bleeding.
  c) Day case hysterectomy
    There has been an increasing tendency for some centres to provide "day case surgery" or "overnight stay" for patients who require hysterectomy. Their aim is to offer a low-cost option for a procedure with a low complication rate for socio-economic reason. Laparoscopic approach allows for precise dissection, good haemostasis and inspection of the vaginal vault at the end of the hysterectomy and therefore it can minimise complications and avoid repeat operation. Laparoscopic approach also facilitates early mobilisation by avoiding the discomfort of a large abdominal incision and thus allows for early discharge from the hospital. This in turn minimises the burden on patients themselves, their employers and their families by allowing early resumption of routine activities. Length of hospital stay is one of the main clinical indicators and measures of efficiency and is a major determinant of the resources needed to run a service. There have been studies on the feasibility of out-patient LH. This out-patient approach is found to be well tolerated, safe and can be performed cost effectively in ambulatory surgery centres, even in rural areas.10 It has been suggested that development of a protocol incorporating patient selection, pre-operative and post-operative patient counselling, a caring family environment, and a round-the-clock medical telephone back up are pre-requisites.32
  d) Learning curve of laparoscopic hysterectomy
    Doctors who offer LH to their patients should be competent to ensure good results. The learning process for any new procedure consists of mastering the theory, surgical technique and the careful adherence to a step-by-step approach. The same process applies to the learning of LH. One should go for didactic training from post-graduate courses and video demonstrations, receive hands-on training, which includes assisting in LH procedures and then operating under supervision. The acquisition of laparoscopic experience is a process that can be evaluated by learning curve. This curve describes the ability to adopt a new technique based on a scale of time and quality, and it is used to evaluate the evolution of training in a new surgical practice. The impact of the learning curve of LH on the duration of surgery is gradual.33 A training period is necessary to standardise the operating procedure, to put in place methods of avoiding complication and to reach a plateau of surgical skill. It has been suggested that at least 20 cases of LH performed under supervision are necessary to allow for the encounter of a wide enough variation in pelvic pathologies to capture both the basic surgical technique and other modifications.34 The experience of performing 80 cases of LH is needed to allow the learning process to stabilise and the time curve to reach a plateau.35,36

Conclusion

Hysterectomy is the treatment of choice for certain gynaecological conditions. The predicted advantages must be carefully weighed against the possible risks of the surgery and other treatment alternatives. In the properly selected patient, the result from surgery should be an improvement in the quality of life. The choice of approach for hysterectomy should be based on the surgical indication, the patient's anatomic condition, data that support the selected approach, patient's informed preference, and the surgeon's training and experience. The vaginal approach which is associated with fewer complications and shorter hospital stay and recovery periods should be emphasised and the training for such approach to gynaecological surgeons should be provided in university teaching hospitals. On the other hand, LH, as a means of avoiding the need for laparotomy, permits the surgeon to undertake more precise and accurate surgery and thus improves surgical outcome. Complications in performing hysterectomy should be avoided if at all possible. Management of complications by itself carries financial commitment and possible legal implications. Therefore, one must attain a very high standard of medical practice with respect to suitability of the surgery, operative techniques, and the post-operative management. Surgeons nowadays have to be capable of performing open, vaginal and laparoscopic surgical techniques in order to offer to the patient the best treatment option according to the pathology to be treated and her anatomical status. The final factor is patient choice. Today's "typical" patient is an intelligent and well-informed consumer who is prepared to seek as many opinions as necessary until she is satisfied with the recommendation. Treatment alternatives should be fully discussed and made available. Surgeons who do well are the ones willing to discuss these options and offer these options to the patients as appropriate.

Key messages

  1. Hysterectomy is a common gynaecological operation performed for various indications.
  2. Hysterectomy has traditionally been performed by either the vaginal or abdominal approach. Laparoscopic approach has recently developed as a third alternative.
  3. Family doctors should be aware of available treatment options and their relative merits and be able to communicate these confidently to their patients.
  4. The trend is towards minimal trauma and faster recovery.
  5. The goal is improvement in surgical outcome and patient satisfaction.

Eric T C Lee, MBBS(HK), FRCOG, FHKCOG, FHKAM(O&G)
Specialist in Obstetrics & Gynaecology in Private Practice

Correspondence to: Dr Eric T C Lee, 1501 Prince's Building, Central, Hong Kong.


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