Colovaginal fistulas are uncommon but can have significant morbidity with abdominal abscesses, sepsis and even death. The most frequent causes are diverticular disease followed by colorectal and gynaecological cancer. It usually presents with passage of stool and/or gas through the vagina, but abdominal pain and fever may also be present. Although an early diagnosis is crucial for good outcome, diagnosis may be delayed since there is no gold standard diagnostic tool.
Because of its rarity there are a lack of prospective studies evaluating the best treatment option: multi-stage or single-stage repair; laparotomy or laparoscopy.
"The American Journal of Surgery" published this year a retrospective study from the University Hospitals Cleveland Medical Centre, Cleveland Clinic, with the objective of evaluate the outcomes from different surgical treatment options. Yuxiang Wen et al. included 27 patients with colovaginal fistula treated between 2006 and 2015. Etiology was similar to literature data, with diverticular disease accounting for 89% of cases. An important data is that 74% of patients had a prior hysterectomy, which represents a risk factor for fistula mainly in inflammatory cases like diverticulitis, because there is no uterus for protection.
There aren't studies about the use of laparoscopy in this setting, even though, the authors used this approach in 19 patients (70%), leaving the open surgery for the remaining 8 (30%). Decision for laparoscopy was solely a surgeon's option. Conversion rate was 42%. Surgical options were:
one-stage surgery in 11 patients (9 laparoscopy / 2 open)
two-stage surgery with diverting loop ileostomy in 8 patients (7 laparoscopy / 1 open)
two-stage surgery with Hartmann's like procedure in 8 patients (3 laparoscopy / 5 open)
From this first analysis it is easy to conclude that several surgical options are possible, and that the authors have experience in all, allowing for a good comparison.
According to Yuxiang et al. data, patients submitted to "straight laparoscopy" had shorter length of stay, increasing in cases of "conversion laparoscopy" and open surgery. 30-day complications rate was 32% and 63% for laparoscopy and open surgery respectively (p=0,1). An interesting data from this study is that there were only two cases of post-operative ileus and two cases of re-operation, all in the laparoscopic group. However the authors do not say if those cases occurred in "straight laparoscopy" or "conversion laparoscopy" group. Did the post-operative ileus occurred after conversion? We do not know... but is a possibility.
From this paper two important ideas emerge. First there are several surgical options to treat colovaginal fistulas (one-stage or multi-stage surgery) with similar outcomes, secondly laparoscopy is a valid option but the authors present a huge conversion rate. Why?
In worldwide literature a conversion rate of 5.5% to 29% is reported. According to the authors there are two reasons for the 42% conversion rate: adhesions and small sample size. The last reason is a contrasense from the authors, since Yuxiang state since the beginning that this is one of the largest series in the literature. But other reason exists that the authors present with this sentence: "...with increasing experience and proper patient selection, the conversion rates can be decrease...".
I believe increasing experience will also lead to a proper selection of patients, and this proper selection is the key to reduce conversion rate. Surgeons worldwide are trying to use laparoscopy in all cases, some of them forgetting that open surgery exists. Indications for laparoscopy have increased since its beginning due to an extreme enthusiasm, but open surgery still has clear indications. Knowing whose patients can benefit from laparoscopy or open surgery is crucial to have low conversion rates. A good surgeon must decide properly and not be blinded by his laparoscopic ego. Why begin laparoscopic when open surgery is the known end? Even though, Yuxiang et al. say that laparoscopy can facilitate splenic flexure mobilisation which will limit the extent of incision when conversion is decided. We shall think on this...
A final word about the one-stage and the multi-stage surgical options. Although they have similar outcomes, the decision to perform a one-stage surgery with resection and anastomosis will depend on patient's clinical condition at time of surgery. Hemodynamic instability and associated peritonitis are factors that should indicate a multi-stage surgery, a Hartmann's like procedure, I think. Do not use the same surgery in all patients... Adapt!
Link to PubMed:
Dr. Carlos Eduardo Costa Almeida
General Surgeon