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Chapter 30

Laparoscopic Surgery

John L. Flowers

W. Bradford Carter

David D. Neal

James A. Warneke

I History

A Technical advances

The idea of visual inspection of the abdomen without open celiotomy was demonstrated by Kelling in 1901. He performed peritoneal “celioscopy” of a canine abdomen by using a cystoscope after air insufflation. In 1910, H. C. Jacobaeus used this technique on humans.

In the 1940s, Goetz, and later Veress, developed a spring-loaded obturator needle for safe insufflation. On penetration of the peritoneum, the obturator springs over the needle to prevent inadvertent perforation or laceration of the abdominal organs. Coupled with the gas -flow insufflator with continuous pressure monitoring designed by Semm in 1964, this advance allowed for the establishment and maintenance of a controlled pneumoperitoneum.

When fiberoptic light sources replaced incandescent lights in the 1960s, a new generation of laparoscopic exploration and procedures became possible. The addition of computer chip cameras greatly facilitated resolution of the video image, and fine detail and precise surgery became a reality.

B Operative milestones

In the 1960s, Semm replaced 75% of open gynecologic operations with laparoscopy , with an overall complication rate of 0.28%. This demonstrated the safety and cost effectiveness of laparoscopy.

Laparoscopic appendectomy was pioneered by DeKok (1977) and Semm (1982). Use of laparoscopy decreased removal of normal appendices by 50% in young female patients who presented with equivocal signs of appendicitis.

Laparoscopy in general surgery was first used for liver biopsy under direct vision.

Warshaw used laparoscopy to stage pancreatic cancer in 1986, with an accuracy of 93%.

Laparoscopic cholecystectomy was first performed in Europe; initially by Erich Muhe (1985) in Germany, then by Dubois, Mouret, and Perrisat (1987) in France. The procedure was introduced and popularized in the United States by McKernan and Saye (1988), and Reddick.

By the early 1990s, the technical feasibility of a laparoscopic approach was demonstrated for virtually all major open abdominal surgical procedures. Since that time, research has focused on the appropriate indications for laparoscopic procedures and documentation of complication rates and cost -effectiveness of the laparoscopic approach. Significant progress has been made in the areas of video technology, laparoscopic surgical instrumentation, and the physiology of laparoscopy as well.

II General Principles

A Differences between laparoscopy and laparotomy

A critical concept in understanding laparoscopy is that it is merely a different method of surgical access to the abdominal cavity. It is not a fundamentally superior technology and does not replace laparotomy. Like all other procedures, it has advantages and disadvantages when compared with standard laparotomy. The fundamental technical differences between laparoscopy and laparotomy are:

Most of the disadvantages of laparoscopy are the result of the technical and mechanical factors that, ironically, are also responsible for the advantages of laparoscopy. Cumbersome instruments that are small in diameter must be inserted at a fixed angle through the abdominal wall. The use of suction is limited by the need for a constant pneumoperitoneum in order to see the operative field. Other disadvantages are:

Tactile sensation is lost. This is the single biggest disadvantage of laparoscopy. The inability to place a hand in the abdomen and feel tissue makes it very difficult to locate masses and find correct tissue planes. It also decreases the safety of blunt dissection and increases operative time.

Depth perception is diminished. The use of a television monitor makes laparoscopy twodimensional. Tasks requiring fine motor skills, such as sewing and dissection around major blood vessels, are more difficult than during laparotomy.

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Hemostasis is difficult. Intraoperative bleeding during laparoscopy is harder to manage for two reasons. Sudden severe hemorrhage is nearly impossible to control, as a hand cannot be used to tamponade bleeding and the ability to suction is limited. Second, limited means are available to manage the constant low -level bleeding that may occur in a patient taking aspirin or in a patient with an acute inflammatory process such as acute cholecystitis.

Suturing is difficult. Several factors make laparoscopic suturing substantially more difficult and time consuming than suturing during open surgery. These include fixed angles of instrument insertion; long, cumbersome needle holders; loss of depth perception; and the need for a cooperative camera holder.

Laparoscopy is resource intensive. Compared with laparotomy, laparoscopy requires relatively delicate and expensive equipment that requires more knowledge and sophistication on the part of the operating room staff to operate and maintain.

Cost-effectiveness of laparoscopy is uncertain. In general, laparoscopic procedures use more expensive equipment and supplies and more disposable instrumentation than laparotomy, increasing the in -hospital costs associated with laparoscopy. This cost increase is amplified by longer operating times seen during the surgeon's learning curve. Theoretically, this cost increase will be offset by more rapid return to normal activity and lower complication rates, though this is difficult to objectively measure. The true cost -effectiveness of laparoscopy will only be determined by numerous outcome studies on a procedure -by-procedure basis.

Many of the disadvantages of laparoscopy can be offset to some degree by the use of additional technologies, such as intraoperative endoscopy and laparoscopic ultrasound during laparoscopy. As newer technologies are developed, their usefulness in overcoming current disadvantages of laparoscopy will be evaluated.

D Patient preparation

Preoperative preparation for laparoscopic surgery is essentially the same as for laparotomy. Before surgery, the patient's overall physical condition is assessed , and special attention is paid to:

Optimal stabilization of underlying medical problems

Assessment of fluid and electrolyte balance

Assessment of coagulation status

General anesthesia is employed in nearly all advanced laparoscopic procedures. Pneumoperitoneum is poorly tolerated in awake patients because of the discomfort of abdominal distention and the resulting sensation of dyspnea as well as shoulder pain caused by diaphragmatic irritation. Local anesthesia may be used with success in properly selected patients:

Diagnostic laparoscopy, especially short procedures limited to the pelvis

Conscious pain mapping for chronic abdominal pain

Some types of extraperitoneal inguinal hernia repair

Intraoperative conduct

The abdomen is prepped and draped widely in all cases so that an urgent laparotomy can be performed if necessary.

An orogastric or nasogastric tube and urinary catheter are inserted to decompress the stomach and bladder in order to avoid injury to these structures during creation of the pneumoperitoneum.

Antithromboembolic pumps are applied to the lower extremities to minimize the possibility of deep venous thrombosis (DVT). Physiologic changes occur during laparoscopy that create the potential for increased risk of postoperative DVT, but the true incidence of DVT and pulmonary embolism following most laparoscopic operations is unknown. All patients undergoing laparoscopic surgery should be considered at “moderate risk” for postoperative DVT. At the present time, the same general recommendations that are widely used for DVT prophylaxis during open surgery should be used during laparoscopic procedures.

Appropriate anesthetic monitoring is necessary, especially end -tidal CO2 monitoring. Patients with underlying cardiopulmonary diseases are at risk for acidosis, and a lower threshold

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for use of more invasive devices such as arterial lines and pulmonary artery catheters is necessary in this group.

E General operative technique

Though every surgical procedure is different, all laparoscopic procedures share several common steps:

Room setup. Attention to detail is critical. Patient position, placement of television monitors, location of the operating team, and preoperative testing of the video system to ensure proper function can all make the difference between a failed or successful procedure.

Establishment of intra -abdominal access. Though laparoscopy may be performed by using one of several specialized mechanical abdominal wall lifting devices, virtually all laparoscopic procedures performed today use a pressurized carbon dioxide (CO2 ) pneumoperitoneum to elevate the abdominal wall and allow visualization of the peritoneal cavity.

CO2 is used because it is readily available, inexpensive, and does not support combustion. It also is

absorbed readily by the peritoneal cavity, has a high diffusion coefficient, and is rapidly excreted by respiration. Nitrous oxide and inert gases such as argon have also been used but are not widely popular today. Filtered CO2 is insufflated into the peritoneal cavity at a pressure of 12–15 mm Hg in

adults. Higher pressures may impede venous return and cardiac output.

Safe, airtight entry into the peritoneal cavity is necessary to create a pneumoperitoneum. Any of three common methods may be used:

Closed pneumoperitoneum method. An umbilical incision is made, and a spring-loaded obturator needle (Verres needle) is inserted through the abdominal wall into the peritoneal cavity. CO2 is insufflated through the needle until the desired pressure is achieved. The Verres

needle is removed, and an appropriate-sized operating port is placed through the incision into the abdomen.

Laparoscopic -assisted method. A specialized disposable operating port with a transparent plastic cutting tip is necessary. A laparoscope is placed in the operating port while the port is advanced under laparoscopic guidance directly through the abdominal wall. Gas is then insufflated directly through the operating port into the peritoneal cavity.

Open pneumoperitoneum method. A 10 - to 20 -mm incision is made at the umbilicus, and standard surgical instruments are used to dissect directly through the abdominal wall under direct vision into the peritoneal cavity. A specialized operating port with a blunt obturator and cork-shaped attachment (Hasson cannula) is used to prevent bowel injury and gas leakage around the site, which tends to be less airtight.

Exploratory laparoscopy. After establishment of pneumoperitoneum, a few minutes are taken to perform diagnostic laparoscopy. The posterior aspect of the anterior abdominal wall and the surfaces of organs are carefully inspected for abnormalities. Special attention is paid to the area of the initial puncture into the abdomen to check for entry trauma. Visualization of these structures is often superior to that allowed with standard abdominal incisions.

Insertion of accessory operating ports. Anywhere from three to six total ports are necessary to accomplish most advanced laparoscopic procedures. Their position varies according to procedure and the patient's body habitus. In general, placement of ports on the arc of a circle with the target organ at its center will allow a successful result.

Hand-assisted laparoscopic surgery (HALS), also known as “handoscopy,” is a hybrid alternative to conventional laparoscopy. After starting a typical laparoscopic procedure, a small laparotomy incision (6–8 cm) is made that allows the surgeon to introduce his hand into the abdomen. This allows exposure and dissection maneuvers with the surgeon's hand while under videoendoscopic control. HALS requires the use of a specialized baglike device that provides an airtight seal around the incision and the surgeon's wrist and forearm while maximizing freedom of movement.

Advantages of HALS. Restores tactile sensation; improves traction, dissection, and tissue exposure; improves control of bleeding; aids handling and extraction of large or bulky specimens.

Disadvantages of HALS. Requires additional incision that increases surgical trauma; alters port placement and operative strategy; presence of surgeon's hand minimizes free space in abdomen; induces hand and back fatigue in surgeon; increased costs due to pneumatic sleeve

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At the present time, HALS has not been widely adopted as an alternative to traditional laparoscopy. It is used mainly to prevent conversion of difficult laparoscopic cases to laparotomy and may have a role in training laparoscopic surgeons in new procedures.

F

Relative contraindications are factors that increase the risk of complications or exacerbate comorbid conditions. They apply generally to most laparoscopic surgical procedures.

Severe cardiopulmonary disease. The increased abdominal pressure associated with pneumoperitoneum will decrease venous return and worsen pulmonary compliance, causing complications such as acidosis, hypotension, and arrhythmia in these patients.

Generalized peritonitis is usually best treated with laparotomy, although diagnostic laparoscopy is useful in equivocal cases.

Prior abdominal operations and adhesion formation increase the technical difficulty and potential danger of laparoscopy. Severe adhesions may make it difficult to place operating ports in proper position and limit the potential working space in the abdomen. They can also increase operating time and increase the likelihood of injury to abdominal organs. Unfortunately, it is not possible to predict the number or severity of intra -abdominal adhesions prior to surgery. Ultimately, the surgeon's judgment is needed to decide whether persisting with a laparoscopic approach or converting to laparotomy is the best choice when faced with significant adhesions.

The risk of hemorrhage in severe coagulopathic states is a contraindication for laparoscopy. These patients should be treated with open techniques that allow direct intervention at potential bleeding sites.

Morbidly obese patients have a very thick abdominal wall, which can hinder operating port placement and free movement of laparoscopic instruments. Excessive intra -abdominal pressure (>20 mm Hg) may be necessary in some patients to elevate the abdominal wall and achieve adequate visualization of the peritoneal contents. The emergence of laparoscopic bariatric surgery over the past several years has led to increased use of laparoscopy in this patient population.

The enlarging uterus of advanced pregnancy may preclude sufficient intraperitoneal space to perform laparoscopic procedures. Most surgeons do not recommend the use of laparoscopy past the 20th week of gestation.

However, laparoscopic appendectomies and cholecystectomies have been performed successfully during the second trimester and even in the early third trimester.

Laparoscopy does not appear to add additional risk to the fetus greater than that experienced during open abdominal procedures.

Portal hypertension , especially when associated with varices, significantly increases the risk of hemorrhage and is best approached with traditional open surgical techniques.

G Physiologic changes associated with pneumoperitoneum

Carbon dioxide insufflation and absorption through the peritoneum produces hypercarbia and acidosis , although this quickly resolves postinsufflation.

The pneumoperitoneum produced by pressure insufflation will decrease venous return by compression of major retroperitoneal veins, thus decreasing cardiac output. Decreased flow rates and velocities are also seen in major veins of the legs and pelvis. This is one of the factors that may predispose patients to postoperative DVT.

The pneumoperitoneum also increases systemic vascular resistance and increases mean arterial pressure.

Respiratory function is compromised by decreased pulmonary compliance, due to the elevation of the diaphragm that occurs during pneumoperitoneum.

H Immunologic and metabolic effects of laparoscopic surgery

Numerous studies in both animals and humans have shown that a laparoscopic surgical procedure results in significantly less surgical trauma and physiologic stress than an equivalent open surgical procedure. One area where these differences can be objectively measured is in the metabolic and immune response of the host. Potential advantages of laparoscopy include:

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