Introduction

The idea of looking inside the body is old but surgeons had to wait until 1806 (first cystoscopy by Bozini) to be able to perform it. Then, one had to wait until the early 20th century to take the risk of entering the abdomen (Kelling in Dresden, 1901). The first human laparoscopy was done only 12 years later. In 1987, Mouret and Dubois in Lyon, successfully performed the first laparoscopic cholecystectomy. This gave the real start to Mini-invasive surgery. Yet in human, mini-invasive surgery has become the gold standard for many operations. The development of new instruments allowed more sophisticated surgeries to be done. Nowadays, the use of Robots has become the rule for many surgeries and even tele-surgery could be performed. The advantages of mini-invasive surgery have been described and usually include smaller incisions, better visualization, less post-operative pain and infection, and shorter hospital stay.

Despite the advent of newer laboratory tests, imaging techniques and ultrasound guided fine needle aspiration capability, laparoscopy remains a valuable diagnostic tool. In the cancer patient, it can also provide staging information. Moreover, in the surgical patient, laparoscopy can be readily used therapeutically for drainage, partial or total organ removal. In the trauma patient, laparoscopy can be used as a rapid method to evaluate the extent of the damage. Despite this, laparoscopy may not always replace a complete abdominal exploratory as a complete exploration might not be possible.

Laparoscopic Exploration

Before trocar placement hollow organs, i.e., stomach or bladder should be decompressed to avoid injury and improve visualization. The key to obtain adequate exposure is the use of gravity. Bringing the head up helps inspecting the cranial abdomen. Bringing the head down (Trendelenburg) and looking caudally allows a better exploration of the pelvic organs. Tilting the patient 45 degrees to the left or right will greatly facilitate examination of the para-lumbar fossa. A full lateral recumbency can be used when exploring adrenal glands, ovaries, kidneys. Combining the tilt with the aforementioned head-up or head-down positions will further enable the operative team to visualize the target areas.

Although a quick abdominal exploration can be done with a one hole (operative laparoscope) technique, most often a laparoscopic exploratory will require the use of 3 ports, one for the camera and two ports for grasping and/or retracting instruments. Additional ports can be necessary to help with tissue retraction.

After gaining access to the abdomen, the peritoneal surfaces, the omentum, liver, diaphragm are inspected. Any redness, inflammation, fluid accumulation, adhesion, are noted. With the telescope in the abdominal cavity, careful examination of the contents is then performed. The site of entry for the second (accessory) portal is then selected. This location is determined by the ancillary procedures that are to be performed. For the placement of the second and the third cannulas, the trocar entry is controlled from inside the abdomen.

"Running the bowel" may seem difficult for the beginner. Moving the omentum cranially is helpful. This is accomplished by directing the scope to the right caudal quadrant and grasping and moving the omentum cranially. Due to the presence of the duodenocolic ligament and overlying jejunum, it is not usually possible to trace the entire ascending duodenum. The ileocecal fold, the antimesenteric ileal artery, and the duodenocolic ligament can then be used to verify if the evaluation has been fully completed.

Laparoscopic Biopsies

Several studies have been conducted to validate the superiority of laparoscopic-obtained biopsy samples compared to fine needle or ultra-sound guided biopsies. Liver, kidney, and spleen biopsies can be easily performed using a two or a one-hole laparoscopy. Laparoscopy is also used in oncology to stage the extent of primary or metastatic malignancy. Laparoscopy may reveal small (0.5 cm or less) metastatic lesions, peritoneal metastases, or other organ involvement not easily observed by other techniques. Unexplained abdominal effusion is an additional indication for laparoscopy when other diagnostics to determine the cause are unsuccessful. In these cases, peritoneal biopsies are usually indicated. Finally, biopsies from hollow viscus are best done by laparoscopic-assisted technique.

Contraindications for Laparoscopic Explorations

In general, a laparoscopic exploratory should not be attempted in an unstable patient as an emergency intervention. An open approach is then best advised, or a laparoscopic approach after the patient's status has improved. For example, one may consider laparoscopic techniques to evaluate blunt trauma patients or penetrating peritoneal wounds in stable patients following adequate resuscitation. In these cases, a laparoscopic exploratory can also be combined with a diagnostic peritoneal lavage. Ascites, abnormal clotting times and poor patient condition are relative contraindications. Severely distended bowel loops or extensive adhesions may also be a contraindication to a laparoscopic approach. In these patients, an open approach, or perhaps a hand-assisted laparoscopic approach, may be more appropriate. Generalized septic peritonitis or equivalent conditions where aggressive and prompt surgical interventions are requested are current contraindications. However, some patients that are at high risk for surgical exploratory actually may become good candidates for a less invasive laparoscopic procedure.

Laparoscopy: Is it For the Practitioner?

On many elective surgeries (ovariectomy, ovario-hysterectomy, cryptorchidectomy), as well as on some specific procedures (pericardectomy), pain scores and behavior scores have been shown to be in favor of mini-invasive approach. In other procedures, high levels of evidence are still lacking because of lack of sufficient number of cases. Nevertheless, the trend is that mini approaches, if not detrimental to the patient, reduce pain and morbidity.

For the owners, the idea of mini-invasive surgery as well as the idea of offering the « state of the art technology » is very positive. Owners easily compare human surgery with veterinary surgery and expect for their pet what they want for themselves. Placing a scope into a cavity has brought over the years a tremendous amount of information. The practitioner willing to start with mini-invasive surgery should start with rigid endoscopic examination: urethro-cystoscopy, otoscopy, rhinoscopy, laryngo-pharyngoscopy, bronchoscopy. Then, further progresses can be achieved by performing intra-abdominal biopsies: liver, lymph node, pancreas...Once this has been done, elective surgeries can be offered: ovariectomy, cryptorchidectomy.

Conclusion

Over the past twenty years, mini-invasive surgery has represented a major progress in the diagnosis and treatment of surgical diseases. In small animal surgery, practitioners shall benefit of it and shall offer it to their clients. Going step by step, getting trained in training centers, not being too ambitious when getting started are the keys for efficient progresses and successes.