- Clinical science
Laparoscopic surgery is a minimally invasive technique used to perform surgical procedures within the abdominal cavity, utilizing specialized instruments introduced through small incisions made on the abdominal wall. The abdominal cavity is first accessed using a trocar or a Veress needle, most commonly in the midline (peri-umbilical region). The peritoneal cavity is then insufflated with carbon dioxide (CO2). A fiber-optic instrument (laparoscope) is inserted into the first trocar to visualize the abdominal cavity and to allow for other ports to be created under direct vision. Laparoscopy is often the preferred diagnostic procedure for most elective gastrointestinal and gynecological surgeries. It is contraindicated in patients with shock, cardiac/pulmonary failure, and in cases of dilated bowel loops/perforation peritonitis. There are several advantages of laparoscopy over laparotomy as the incisions used are much smaller (e.g., less postoperative pain, fewer respiratory complications). However, the surgery is technically more challenging and complications (e.g., hemorrhage, bowel injury) are difficult to control laparoscopically. Complications unique to laparoscopy (secondary to CO2 insufflation of the peritoneal cavity) include hypercarbia, pneumothorax, pneumomediastinum, venous air embolism, and postoperative shoulder pain. Proper patient selection and good surgical technique minimize the risks and complications of laparoscopy.
- Nearly all elective abdominopelvic surgeries can be performed laparoscopically.
- A few examples include:
- Gastrointestinal surgery: e.g., cholecystectomy, appendectomy, hernia repair, bowel resection
- Gynecological surgery: e.g., hysterectomy, oophorectomy
- Urological surgery: e.g., nephrectomy, pyeloplasty
- Diagnostic laparoscopy: allows direct visualization of the abdominal cavity, as well as biopsy of suspicious areas (lymphadenopathy) or collection of peritoneal fluid (for culture or cytology) through small incisions in the abdominal wall. Commonly used to avoid laparotomy in the following situations →
- Absolute contraindications
- Cardiac failure
- Pulmonary failure Helium has been proposed as an alternative insufflating gas in patients with pulmonary failure. But it's safety profile is yet to be established
- Pregnancy/large pelvic masses
- Soft tissue infection at port sites
- Expected (extensive) adhesions from a previous abdominal surgery Open technique for trocar insertion is recommended in this group of patients if the surgeon decides to operate laparoscopically.
- (may be associated with increased risk of vascular rupture)
We list the most important contraindications. The selection is not exhaustive.
- Anesthesia: (most common), with/without may be used in some cases
Access to the peritoneal cavity (laparoscopic entry): A trocar/Veress needle is inserted through the abdominal wall (generally midline) into the peritoneal cavity.
- Open technique (Hassan technique): The trocar is inserted under direct vision.
- Closed technique: entry into the abdomen using a Veress needle
- Visual entry technique: Uses a transparent trocar, connected to a laparoscope, to directly visualize each layer of the abdominal wall as it is being advanced
Creating a pneumoperitoneum: The peritoneal cavity is insufflated with carbon dioxide (CO2). The safety profile of the other gasses is still under consideration and they each have their advantages and disadvantages. E.g., cautery cannot be used if NO is the insufflating gas since it is combustible. The risk of gas embolism, though rare, is higher with argon and helium since these gasses are insoluble in blood.
- Allows visualization of abdominal contents and creation of operative space
- Raises intra-abdominal pressure due to the insufflation of gas within a closed cavity
- Creation of other port sites
- Removal of instruments and trocars
- Evacuation of pneumoperitoneum
- Closure of the port sites: Fascia of port sites > 5 mm must be sutured at the end of the surgery.
Advantages of laparoscopy over laparotomy include:
- Less postoperative pain, which leads to:
- Shorter duration of postoperative ileus
- Better cosmetic outcome (smaller scars)
- Less intra-abdominal adhesion formation
Disadvantages of laparoscopy are mainly technical:
- The surgical field is converted to a two-dimensional image on a monitor.
- Technically more challenging than laparotomy
- Difficulty in controlling intra-operative hemorrhage
- Laparoscopy-specific complications (see below)
- More expensive than a laparotomy procedure
- Injury to adjacent organs (e.g., blood vessels, bowel, bladder, solid intra-abdominal organs)
- Aspiration of gastric contents
Intra-abdominal pressures > 20 mmHg should be avoided as it may potentially lead to:
- The diaphragm being pushed upwards → decreased total lung volume and increased airway pressure
- Compression of the IVC → decreased venous return to the heart → decreased cardiac output
- Increased systemic vascular resistance (compression of arteries) and release of catecholamines (adrenaline, noradrenaline) → tachycardia
- Compression of renal arteries → decreased glomerular filtration rate → decreased urine output
- Subcutaneous emphysema
- Hypercarbia and
- Postoperative complications
We list the most important complications. The selection is not exhaustive.