Chapter 5 Diagnostic Laparoscopy. Operative Techniques

 Chapter 5 Diagnostic Laparoscopy

GENERAL PRINCIPLES

Diagnostic laparoscopy is the surgical examination of the pelvis and abdomen

with the intent to diagnose various pathologies.

Differential Diagnosis

■ Ruptured ectopic pregnancy

■ Adnexal masses—benign versus malignant

■ Adnexal torsion

■ Endometriosis

Anatomic Considerations

■ Aorta

■ The aortic bifurcation is located cephalad to the umbilicus in 90% of

nonobese, supine patients.

■ In a patient with body mass index (BMI) <25 kg/m2, the abdominal

wall is approximately 2 to 3 cm thick. At a 90-degree angle, the distance

to the bifurcation is between 6 and 8 cm and directly correlates to the

patient’s BMI. Therefore, an entry angle of 45 degrees is recommended to

avoid vascular injury.

■ In a patient with BMI >25 and >30 kg/m2, the distance from the

umbilicus to the aortic bifurcation averages 10 and 13 cm, respectively.

■ Inferior epigastric vessels

■ See Figure 5.1.

■ The deep inferior epigastric vessels originate from external iliac vessels

and travel along the anterior abdominal wall on the inferior side of the

rectus abdominus.

■ Their path begins medial to the insertion of the round ligament into

the deep inguinal ring.

Figure 5.1. Laparoscopic view of the anterior abdominal wall: Inferior epigastrics

traveling through lateral umbilical fold.

■ At the level of pubic symphysis, the vessels are lateral to the rectus

abdominis.

■ At the level of the anterior superior iliac spine (ASIS), the vessels are

an average of 3.5 (2.6 to 5.5) cm from the midline.

■ During laparoscopy, the deep inferior epigastric vessels can be identified

in the lateral peritoneal umbilical folds bilaterally.

■ Iliohypogastric and ilioguinal nerves

■ The iliohyogastric nerve provides sensory innervation to the oblique

abdominal muscles and the suprapubic skin.

■ The ilioguinal nerve provides sensory to the transversus abdominis,

internal oblique, skin of medial thigh, and the vulva.

■ Classically, when a nerve has been injured or entrapped, patients report a

burning sensation near the incision sites that radiates toward the groin.

■ Both nerves originate from L1 vertebra, after emerging from the lateral

border of the psoas muscle. They wrap around the iliac crest to pierce

through the transversus abdominis and internal oblique.

■ The ilioinguinal nerves emerge 3.1 cm medial and 3.7 cm inferior to

the ASIS. The iliohypogastric emerges 2.1 cm medial and 1 cm inferior

to the ASIS.

■ Both nerves emerge near classic locations for lateral trocar placement.

IMAGING AND OTHER DIAGNOSTICS

■ Transvaginal pelvic ultrasound is the imaging modality of choice.

■ The primary entry site may be altered by a pelvic mass, an enlarged

uterus, or suspected adhesions revealed by ultrasound.

■ A visceral slide test performed with ultrasound can be used to

preoperatively identify dense subumbilical adhesions in a high-risk

patient. During this test, an echogenic area of bowel or omentum isidentified near the umbilicus on ultrasound. The patient then performs

exaggerated inhalation and exhalation. Longitudinal movement of this

location greater than 1 cm corresponds to a low risk of obliterating

subumbilical adhesions.

■ A urine pregnancy test is recommended for premenopausal patients who

have a uterus and have not undergone a sterilization procedure.

■ A positive pregnancy test does not contraindicate surgery, but

intrauterine procedures should not be performed.

PREOPERATIVE PLANNING

■ Obtain a surgical history. History of a prior laparotomy or multiple

surgeries is a significant risk factor for laparoscopic complications.

■ Obtain a medical history, especially note cardiovascular and pulmonary

diseases.

■ Trendelenburg position may be limited in a patient with poor

cardiopulmonary function or extreme obesity. It is important to

preoperatively counsel these patients about these inherent limitations and

the possibility of conversion to laparotomy.

SURGICAL MANAGEMENT

Positioning

■ Proper patient positioning is essential to ensure patient safety.

■ Position the patient in low lithotomy position using adjustable stirrups.

These stirrups allow for quick and easy position changes and should

neutralize pressure points from the patient’s own leg weight.

■ See Figure 5.2.

■ Ideal low lithotomy position:

■ The hips are flexed with minimal internal or external rotation. Hip

flexion should not be less than 60 degrees and preferably set at 80 to 90

degrees in high lithotomy to avoid compression of the femoral nerve. The

hips should also not be extended beyond 170 degrees in low lithotomy as

this places strain on the lumbar spine.

■ Similarly, avoid excessive abduction of the legs. The angle between

thighs should be limited to 90 degrees.

Figure 5.2. Proper positioning in dorsal lithotomy using padded stirrups. A. The

patient’s elbow is tucked at her side with her hand in neutral position. Additional foam

padding is placed on the most lateral aspects of the elbows and hand prior to securing

or “tucking” the arm. B. Hip flexion: This angle can vary widely for laparoscopic and

vaginal surgeries. However, at its maximum limits should range from 60 to 170 degrees

with flexion preferably at 80–90s degrees in high lithotomy. C. Hip abduction: The angle

between the thighs should be less than 90 degrees. D. Hip rotation: Maintain minimal

rotation. E. Knee flexion: Thigh-to-calf angle should range between 90 and 120

degrees. Additional foam padding is placed on the lateral aspect of each knee to protect

the peroneal nerve. F. Note an egg crate or additional gel table padding is placed to

reduce patient slippage.

■ Knees should be flexed and padded with foam to avoid lateral

compression which can result in a peroneal nerve injury. Knee flexion

should be 90 to 120 degrees. Increased knee flexion can put strain on the

femoral nerve and promote venous stasis in the lower leg.

■ Use an egg crate or gel cover on the top of the surgical table and in

direct contact to the patient’s back to prevent the patient from slipping

while in the Trendelenburg position. Avoid using shoulder supports to

stabilize the patient as these supports can cause brachial plexus injury. A

padded chest strap or large Velcro strap can be placed across the patient’s

chest and secured to the surgical bedframe to prevent slippage in the

obese, but should also allow for maximum ventilation.

■ Tuck the arms to the patient’s side using disposable positioning systems,

sheets, foam, or a combination of the above. Place the wrist in a neutral

position with the thumb anterior. Place padding under the wrist and elbow

to avoid ulnar nerve compression. Take great care not to compress

peripheral intravenous access and to cushion the patient’s fingers from the

table joint. In obese patients, use low-profile surgical sleds or bed

extensions to provide extra support and space to accommodate increased

patient habitus.■ This position allows the surgeon closer proximity to the patient and

protects the patient’s hands, wrists, and joints.

■ Ensure the bed is level and the patient is lying flat.

■ Avoid Trendelenburg position initially as this position shifts the aortic

bifurcation closer to the umbilicus and increases the risk of aortic injury.

■ Confirm a nasogastric tube and Foley catheter are inserted as distention of

these organs increases the risk of injury during surgical entry.

■ Place a uterine manipulator to facilitate uterine mobility.

■ Complex manipulators have been designed to aid in more complicated

operative procedures. In the case of a diagnostic procedure, consider a

reusable low-cost option such as a cervical dilator secured to a tenaculum

or a Hulka tenaculum.

Approach

■ Entry into the peritoneal cavity and establishment of pneumoperitoneum is

the essential first step to all laparoscopies. It also carries the highest risk.

■ The primary entry site is typically at the umbilicus or Palmer’s point.

■ Palmer’s point is located 3 cm below the costal margin in the

midclavicular line. This site has significantly less adipose tissue compared

to the periumbilical area and typically has a smaller skin to peritoneum

distance. It may be preferable in obese patients.

■ Palmer’s point can be utilized when there is concern for adhesions

from prior laparotomy (including cesarean section), large fibroid

uterus, pelvic mass, or prior umbilical hernia repair with mesh.

■ The stomach and liver are the closest structures and are at increased

risk of injury.

■ Relative contraindications to Palmer’s point include splenomegaly,

hepatomegaly, and a known left upper quadrant mass. Adhesions from

prior upper abdominal surgery should also be considered.

■ A supraumbilical site can also be used for the same preoperative risks.

This site is located 3 to 5 cm above the umbilicus in the midline.

■ Adhesions in the infraumbilical area can be as high as 50% after prior

low transverse laparotomy and up to 90% after prior midline laparotomy.

■ Entry techniques in laparoscopy are typically classified as closed or open

entry. Open entry refers to a mini-laparotomy or Hasson approach. Closed

entry is the blind insertion of an instrument into the peritoneal cavity. The

most common methods of both types of techniques will be described below.

■ Multiple studies have affirmed that over 50% of major complications,

specifically bowel and vascular injury, occur at initial entry.

■ No method has been proven to be superior at preventing injuries. We

recommend perfecting one technique to acquire mastery and proficiency,then gradually adding other techniques to your surgical repertoire.

■ Consistency, experience, and good technique lead to safe entry, no

matter the approach.Procedures and Techniques (Video 5.1)

Veress needle

The Veress needle is a thin long needle with a spring-loaded blunt tip that is used

for closed entry. Once this needle is passed into the peritoneal cavity, it is then

used to insufflate the abdomen prior to trocar insertion.

■ To insert the Veress needle, grasp and elevate the abdominal wall. A small skin

incision may be made.

■ With the valve open and the needle at a 45-degree angle, apply gentle inward

pressure to pass the needle through the abdominal wall.

■ A double-click sensation will be felt as the blunt tip passes through the rectus

fascia and then the peritoneum.

■ Confirm entry into the peritoneal cavity prior to initiating insufflation.

■ Aspiration test—Attach a 5-mL syringe with normal saline to the Veress

needle. Aspirate to ensure no blood or fecal matter returns.

■ Hanging drop test—Remove the syringe leaving a drop of saline at the Veress

hub. With the Veress needle valve open, the saline should freely flow into the

needle confirming its placement in the low-pressure peritoneal cavity.

■ Initial opening pressures should measure ≤9 mm Hg (up to 10 mm Hg in

obese patients).

■ A prospective study of 348 cases evaluated the first four mentioned methods

and found a low sensitivity and low positive predictive value for all tests, but

they noted initial pressures were the best at evaluating for extraperitoneal

location. The aspiration test, while not sensitive, still has merit as any finding of

fecal matter or blood allows for rapid recognition of an injury.

■ Following Veress placement into the peritoneal cavity, the abdominal cavity is

then insufflated to 15 to 20 mm Hg. Following insufflation, the initial trocar is

placed.

Primary direct trocar placement

■ Similar to the Veress needle for closed entry, a trocar can be directly inserted

into the abdominal cavity without establishing pneumoperitoneum.

■ Make a small incision at the entry site. Grasp and elevate the abdominal wall and

insert the trocar at 45 degrees.

■ If a noncutting trocar is used, advance the trocar by applying a twisting motion

with simultaneous inward pressure. There will be two distinct losses of resistance

that correlate to traversing the fascia and the peritoneal layers.

■ Remove the obturator and insert the laparoscope to visually confirm peritoneal

entry.■ Multiple studies have shown equivalent or lower rates of injury and complications

for direct trocar compared to Veress needle entry making it a safe alternative.

■ An optical trocar may also be used for direct entry.

■ The optical trocar tip is made of clear, hydrophobic plastic and allows for

visualization of each abdominal layer as opposed to tactile confirmation.

■ The rates of blind versus optical entry injury are equivalent.

■ However, the optical method allows for faster recognition of penetrating

injuries.

Angle of insertion for closed entry

■ The instrument must be inserted at a trajectory that guides it into a safe

anatomical location to avoid puncture injury but also is short enough that the

instrument penetrates the peritoneum.

■ A 45-degree angle of insertion at the umbilicus aims the trocar toward the hollow

of the lumbar and sacral spine. This area carries minimal risk of major vessel

injury. At this angle, failed peritoneal entry is also uncommon in nonobese

patients.

■ However, obesity increases the distance for peritoneal entry, therefore, making

preperitoneal insufflation a more common complication. Hurd et al. preformed an

anatomic analysis using CT and MRI scans of the abdomen. He measured from

the umbilicus to anterior peritoneum and great vessels. Based on his findings, he

proposed 90-degree angle of instrument insertion in obese patients. In their

analysis, they found that due to a significant increase in the abdominal wall width,

the retroperitoneal vessels were at a safe distance from the trocar insertion at 90

degrees, but this angle avoided preperitoneal placement of the entry instrument.

■ This has been the traditional teaching for many years; however, it was recently

challenged by Stanhiser et al. Preforming similar measurements using CT scans,

they purposed that using standard trocars (10 cm) and standard Veress needle

(12 cm), a 45-degree angle could be used up to a BMI of 65. This angle in the

very obese would allow for increased safety from vascular puncture in a patient

population where emergent laparotomy carries increased difficulty and risk.

Open entry (Hasson technique)

■ Make a vertical or horizontal small incision at the umbilicus to accommodate the

diameter of a trocar.

■ Grasp the base of the umbilical fascia stalk with a Kocher clamp.

■ Bluntly dissect the subcutaneous fat from the fascia. Then regrasp the more

caudal fascia with a second Kocher clamp.

■ Elevate the clamps, pulling the abdominal wall away from the intra-abdominal

contents.

■ Make a 10- to 12-mm horizontal fascial incision with a scalpel.■ Place two separate absorbable sutures though the cephalad and caudad

aspects of the fascial incision, respectively.

■ Using S-retractors, bluntly retract the preperitoneal adipose tissue to visualize the

peritoneal tissue. Enter the peritoneum either bluntly or sharply with hemostats

and Metzenbaum scissors.

■ Once entry into the peritoneal cavity is confirmed visually, assess for signs of

accidental injury and digitally palpate the surroundings for adhesions.

■ Finally, place the Hasson trocar with a blunt obturator and secure it to the fascia

using the two fascial sutures.

Placement of secondary trocars

■ See Tech Figure 5.1.

■ The number and placement of additional trocars are determined by the needs of

the procedure. For diagnostic procedures, a single secondary trocar may be

sufficient to manipulate the viscera and adequately visualize all structures.

■ Use a scalpel to make a small stab skin incision large enough to accommodate

the trocar diameter. Holding the trocar in the surgeon’s dominant hand, engage

the fascia at a 90-degree angle to allow for maximum mobility of the port site.

■ Advance the trocar into the peritoneal cavity with a gentle downward twisting

motion, while keeping the tip always in view and in control to prevent accidental

puncture. After the fascia is punctured, aim the trocar toward the pelvis while

completing insertion.

■ The ASIS is an often used reference point. Placing accessory trocars

approximately 3 cm superior and medial to this anatomical point on the

insufflated abdomen decreases injury to ilioinguinal and iliohypogastric nerves

and the inferior epigastric vessels.

■ Two cadaver studies by Whiteside and Rahn mapped the course of these

nerves before and after insufflation. Both studies recommend accessory trocar

placement 6 cm above the pubic symphysis or above the ASIS.

■ The superficial epigastric vessels can be transilluminated and avoided, although

obesity may limit visualization of these structures.

■ Visualize the inferior epigastric vessels laparoscopically by identifying the lateral

umbilical folds. If the vessels are obscured by adipose tissue, identify the

vessels medial to their insertion of the round ligament and trace their cephalad

path.

■ Ports should be placed so that all instruments have at least a 60-degree angle of

intersection in the pelvis.

■ Port sites should be placed at least 5 cm apart. A fist width can be used to

estimate the needed distance between trocars. Instruments can be placed on

the abdominal wall at the proposed trocar sites and aimed at the pelvic target

to aid in optimal site selection to prevent collision of instruments in theoperative field.

Tech Figure 5.1. Accessory port placement. Left side: Anatomy of the pelvic vessels,

ilioinguinal nerve, and iliohypogastric nerve in relation to port placement. Right side:

Ports must be place at least 5 cm apart on the abdominal wall to allow mobility of each

instrument in the pelvis.

Pelvic survey

■ Inspect the pelvis in a systematic manner. Begin with the area of primary entry

and the area just posterior to the abdominal wall entry, regardless of the entry

method. Assess for any evidence of injury.

■ Evaluate the upper abdomen: the liver, gallbladder, diaphragm, stomach, and

bowel. Take particular note of perihepatic adhesions, masses, or enlarged

structures.

■ Place the patient in Trendelenburg position to maximize exposure of the pelvis.

■ Globally survey the pelvis to assess for abnormalities or adhesions.

■ If adhesions are present, address only those that require adhesiolysis in order

to complete the pelvic survey.

■ The systematic survey of all pelvic structures includes pelvic and abdominal

walls. The pelvis is divided into zones based on anatomical boundaries to

prevent exclusion of important structures.■ See Tech Figures 5.2 and 5.3.

■ Using the same systematic approach, the findings for each area should be

described in the operative report.

■ Zone 1: anterior abdominal and pelvic structures with round ligaments limiting the

lateral borders.

■ Evaluate the uterine dome and anterior uterine surface, anterior surface of the

broad ligament, bladder dome, internal ring of the inguinal canals, and the

inferior epigastric vessels.

■ Evaluate the uterus for size and lesions such as fibroids or endometriosis.

■ Retroflexing the uterus may improve visualization of these structures.

■ Zone 2: midline posterior structures located between the uterosacral ligaments.

■ Antevert the uterus with the manipulator and evaluate the posterior surface of

the uterus, posterior cul-de-sac, rectovaginal septum, sigmoid colon, and

presacral peritoneum.

■ The posterior cul-de-sac should be inspected for endometriosis lesions and

peritoneal windows.

■ The entire depth and breadth of the cul-de-sac should be evaluated with a

wide view and also with a zoomed, close-up examination of the tissues, for

adhesions and obliterating endometriosis.

■ Zone 3: the area between the uterosacral ligaments inferiorly and extending

superiorly to the lateral pelvic side walls including the ovaries, fallopian tubes, and

infundibular pelvic ligaments.

■ Evaluate the fallopian tubes, posterior surface of the broad ligament, ovaries,

and adnexal vessels, and ureters.

■ The ovaries should be evaluated on all sides for abnormalities or adhesions.

Place a blunt probe inferior to the infundibular pelvic ligament to flip the ovary

over to evaluate its inferior aspect.

■ Evaluate the fallopian tubes for nodularity or sclerosis. Do not grasp these

fragile structures. Instead, use blunt manipulation. If absolutely necessary, use

a Babcock to grasp only the mesosalpinx and limit traumatic manipulation.

■ Zone 4: pelvic side walls superior to the adnexa.

■ The appendix should be identified and inspected, especially if the patient

suffers from undiagnosed pelvic pain.

■ The survey should be completed before an operative procedure is initiated

since manipulation of the tissues can cause bleeding and obscure initial

findings.

Tech Figure 5.2. Zones of the pelvis.

Tech Figure 5.3. Zones of the pelvis.

Port removal and closure

■ Ports larger than 8 mm require fascial closure with either a suture closure device,

such as a Carter Thomason device, or with direct closure using S retractors,

Kocher clamps, and a delayed, absorbable suture. Always begin with the larger

port sites and remember to switch the insufflation tubing to the smaller caliber

ports to maintain pneumoperitoneum.

■ Following completion of the laparoscopy, remove the ports under direct

visualization to ensure no structures are inadvertently incorporated.

■ To optimally evacuate the pneumoperitoneum, turn off the insufflation, and eithersuction the remaining intraperitoneal gas while the suction device is placed over a

safe viscous or ask the anesthesiologist to have the patient take several deep

breaths while the abdominal wall is compressed. Place the laparoscope in the

final remaining port site and withdraw both the scope and port simultaneously,

ensuring no bowel is entrapped within the abdominal wall.

■ Reapproximate the skin with a small caliber, absorbable suture, or dermal glue.PEARLS AND PITFALLS

Place an intrabladder Foley catheter to gravity drainage and a nasogastric tube to suction

before every procedure. Decrease the potential for puncture injuries by ensuring viscous

structures are decompressed prior to surgical entry.

Proper patient positioning to avoid neuropathic and crush injuries and awareness of light cord

contacts that can cause burn injuries and fire are integral aspects of laparoscopic surgery.

Palmer’s point is an excellent alternative primary entry site. Consider this when there is a failed

entry at umbilicus, in obese patients, or when there are suspected dense periumbilical

adhesions.

Do not initially position the patient in Trendelenburg position since it increases the risk of

vascular injury upon initial entry.

Laparoscopic direct entry with optical trocar is the fastest method of entry and does not

increase puncture risks.

Improves identification of abdominal wall layers particularly with thickened adipose layers.

Puncture injuries are typically recognized faster during this procedure; however, it does not

improve incidence of missed injuries.

When a difficult entry is encountered, immediately turn the insufflation valve to the “off” position

or disconnect the gas from the needle or trocar. Accidental insufflation of a preperitoneal

space will obscure normal anatomic planes and increase the morbidity of the procedure.

Factors that increase complications: number of attempts for surgical entry

Case complexity

Prior abdominal surgery: specifically, history of prior laparotomy

Various entry techniques each have their own advantages but complete mastery of one

technique is the safest and most important skill set to achieve instead of a diverse repertoire.

POSTOPERATIVE CARE

■ Uncomplicated diagnostic surgery is safely performed as an outpatient

procedure.

■ Right upper quadrant pain from residual pneumoperitoneum is common for a few

days and up to a week after surgery. Prescribe nonsteroidal anti-inflammatory and

narcotic medications for incisional analgesia. Depending on the size of port sites,

activity is not significantly limited following surgery and patients are instructed to

resume their normal activities as tolerated.

If the patient is not improving on a daily basis, she should be evaluated in person.

COMPLICATIONS

■ The majority of diagnostic laparoscopy complications occur during initial entry.

■ Entry complications comprise 50% of all laparoscopy complications but theirincidence of 0.3% to 1% still makes these complications rare.

■ Injuries are mostly vascular and bowel punctures, but also include gas

embolism, bladder injury, extraperitoneal insufflation, and failed entry.

■ An open technique avoids the element of blind insertion and therefore was once

thought to be the ideal method to prevent accidental puncture injuries. This has

not been supported by literature. Many studies have shown a lower rate of

vascular injuries, and gas embolism becomes nearly absent with open technique.

Bowel injuries are equivalent or increased with an open technique. The increased

incidence could be due to selection bias as surveys have shown surgeons favor

an open technique for patients with a history of prior surgery when there are

anticipated adhesions.

■ A Cochrane review concluded that there is no evidence that supports the

superiority of any method as the safest form of entry.

■ Experience decreases the rate of complications; therefore, the current

recommendation is to use the techniques that are most experienced and

comfortable in performing.

■ Vascular punctures to major vessels carry the highest mortality risk.

■ 75% of punctures are arterial and, of them, 25% were aortic and 20% were

common right iliac artery injuries.

■ The instrument angle must be maintained in the midline during entry as a slight

deviation can result in peritoneal entry many centimeters laterally and risks

injury to the iliac vessels.

■ Bowel injuries are more common than vascular injuries, and occur in

approximately 0.4% of laparoscopic surgery.

■ Regardless of entry technique, studies estimate 30% to 50% of bowel injuries

go unrecognized during the procedure. The resulting peritonitis and sepsis

from delayed recognition has a mortality rate of 2.5% to 5%.

■ Optical trocars have not mitigated this risk and have a similar rate of missed

bowel injury diagnosis.

■ Obese patients are at an increased risk for failed entry.

■ An open technique can be more challenging due to an increased thickness of

the abdominal wall, preperitoneal adipose tissue, and peritoneal layer.

■ A direct optical trocar entry can be helpful as well as a left upper quadrant

entry.

■ Obese patient may also be limited in their Trendelenburg positioning due to

ventilation challenges.

■ Risk factors that are associated with an increased complication rate:

■ The number of attempts needed to successfully complete the primary entry is

associated with an increase in accidental puncture.

■ Case complexity was a significant risk factor for major complications, minor

complications, as well as conversion to laparotomy.■ Prior abdominal surgery was the only other factor that increased the rate of

major complications (defined as visceral punctures, serious bleeding, death).

■ Obesity does not always prove to be a risk factor in studies; however,

increased rates of failed entry would suggest otherwise.