Exploratory Laparotomy

By definition, an exploratory laparotomy is a laparotomy performed with the objective of obtaining information that is not available via clinical diagnostic methods. It is usually performed in patients with acute or unexplained abdominal pain, in patients who have sustained abdominal trauma, and occasionally for staging in patients with a malignancy.

Once the underlying pathology has been determined, an exploratory laparotomy may continue as a therapeutic procedure; sometimes, it may serve as a means of confirming a diagnosis (as in the case of laparotomy and biopsy for intra-abdominal masses that are considered inoperable). These applications are distinct from laparotomy performed for specific treatment, in which Dr. B C shah plans and executes a therapeutic procedure.

With the increasing availability of sophisticated imaging modalities and other investigative techniques, the indications for and scope of exploratory laparotomy have shrunk over time. The increasing availability of laparoscopy as a minimally invasive means of inspecting the abdomen has further reduced the applications of exploratory laparotomy. Nevertheless, the importance of exploratory laparotomy as a rapid and cost-effective means of managing acute abdominal conditions and trauma cannot be overemphasized.

Indications

Four primary indications for an exploratory laparotomy are noted, as follows.

Acute-onset abdominal pain and clinical findings suggestive of intra-abdominal pathology requiring emergency surgery

In these conditions, exploratory laparotomy is carried out both to diagnose the condition and to perform the necessary therapeutic procedure.

Peritonitis

Patients with clinical features of peritonitis may have pneumoperitoneum on erect chest and abdominal radiographs. They usually have a perforated viscus, most commonly the duodenum, stomach, small intestine, cecum, or sigmoid colon. Exploratory laparotomy is done first to determine the exact cause of pneumoperitoneum, followed by the therapeutic procedure. In the absence of pneumoperitoneum, appendicular perforation and intestinal ischemia are possible diagnoses; a high index of suspicion for possible intestinal ischemia should be maintained.

Intestinal obstruction

Patients with vomiting, obstipation, and abdominal distention are likely to have intestinal obstruction. Abdominal radiographs in these patients may reveal dilated intestinal loops and air-fluid levels. Hernia, especially an incarcerated inguinal hernia, should be ruled out as a possible cause of the obstruction.

Intra-abdominal collections

Patients with pain in the abdomen and fever may have intra-abdominal collections. These are usually detected by means of ultrasonography or computed tomography (CT) and can often be managed percutaneously. A persistently high aspirate or the presence of enteric contents may suggest perforation, and laparotomy may be required to control the source.

Abdominal trauma with hemoperitoneum and hemodynamic instability

Hemodynamically unstable trauma patients with hemoperitoneum should undergo exploratory laparotomy without any delay. They are likely to have intraperitoneal bleeding after injury to the liver, spleen, or mesentery. They may also have associated intestinal perforations that call for emergency repair.

Chronic abdominal pain

Availability of good imaging facilities have restricted the use of exploratory laparotomy in these conditions; however, when limited facilities are available, exploratory laparotomy becomes an important diagnostic tool. These patients may have intra-abdominal adhesions, tuberculosis, or tubo-ovarian pathology.

Staging of ovarian malignancy and Hodgkin disease

The role of surgical staging in Hodgkin disease is controversial, and recommendations are restricted to patients who may be considered for primary radiotherapy as the sole modality of treatment.

Contraindications

The primary contraindication for exploratory laparotomy is unfitness for general anesthesia. Peritonitis with severe sepsis, advanced malignancy, and other comorbid conditions may render patients unfit for general anesthesia.

Technical Considerations

Exploratory laparotomy is sometimes a good diagnostic tool. However, anticipation of the diagnosis is necessary, and a hasty exploration should be avoided if the center is not well equipped to perform the therapeutic procedure that will be necessary if the suspected condition is confirmed.

Nontherapeutic laparotomy is associated with significant long-term morbidity, including adhesive intestinal obstruction and incisional hernia. Consequently, exploratory laparotomy should be performed in accordance with standard protocols and guidelines for laparotomy.

The authors have found that in equivocal cases of acute abdomen, diagnostic peritoneal lavage (DPL) is often helpful in determining the need for exploratory laparotomy. If DPL findings are positive, then an exploratory laparotomy is performed; if DPL findings are negative, the patient is closely monitored.

Periprocedural Care

Preprocedural Planning

The patient's physiologic status at laparotomy is an important determinant of outcome. Accordingly, whenever possible, efforts should be made to optimize the patient's general condition. This includes correction of fluid and electrolyte imbalances, blood transfusions, and bronchodilator nebulizations as required.

Before the procedure, a nasogastric tube and an indwelling urinary catheter are inserted to decompress the stomach and the urinary bladder. Decompression of the stomach reduces the risk of aspiration of gastric contents during induction of anesthesia. The risk of such aspiration is high in these patients because of the emergency nature of the procedure and because of paralytic ileus. Decompression of the bladder reduces the risk that the bladder may be injured as the midline incision is extended inferiorly for better exposure.

Equipment

Exploratory laparotomy is performed in an operating room (OR). The OR should contain anesthetic equipment, overhead lights, electrodiathermy equipment, and suctioning systems. A standard laparotomy tray is usually sufficient for an exploratory laparotomy.

If vascular intervention is anticipated, vascular instruments may be required. If major abdominal organ resection may be needed, appropriate instruments, facilities, and expertise should be available. Similarly, abdominal trauma necessitates major abdominal surgery, for which appropriate infrastructure and expertise are required.

Patient Preparation

Patient preparation includes adequate anesthesia and appropriate patient positioning.

Anesthesia

Exploratory laparotomy is performed with the patient under general anesthesia. Patients who are anesthetized for emergency surgery are at higher risk for aspiration of gastric contents. Adequate care must be taken to empty the stomach before induction. Rapid-sequence induction considerably reduces the risk of aspiration.

Positioning

The patient is placed in the supine position, with the arms abducted at right angles to the body. The lithotomy position may be employed instead when a pelvic pathology is suspected and a simultaneous vaginal or rectal intervention is necessary.

Technique

Exploratory Laparotomy

After appropriate preparation (see Periprocedural Care), exploratory laparotomy is performed as follows.

Midline incision and opening of peritoneum

A vertical midline incision is the best choice: it affords a rapid entry into the peritoneum and is relatively bloodless and safe.The incision may be made in the upper, middle, or lower midline, depending on the anticipated pathology, and may be extended in either direction if necessary. Exposure of the peritoneum should never be compromised in an attempt to keep the incision small.

The skin is incised with a surgical knife. The incision is then deepened through the subcutaneous fat. Electrodiathermy in coagulation mode provides a bloodless access through this layer. The linea alba is identified as a glistening layer deep to the subcutaneous tissues.

Upper midline incision. Incision is deepened through subcutaneous tissue to expose linea alba.

The orientation of the fibers on the linea alba is appreciated; these fibers are directed medially and inferiorly from either side, and the midline is identified as the axis where they criss-cross. This is opened carefully by means of electrodiathermy or heavy Mayo scissors .

Linea alba is divided to reveal preperitoneal fat.

Abdominal incision is completed to reveal intra-abdominal organs.

Every effort must be made to avoid injury to the intraperitoneal contents. This can be done by lifting the peritoneum in 2 straight artery forceps placed close to each other at right angles to the incision. Use careful palpation to ensure that no bowel or omentum is picked up in the artery forceps. In reoperations, extreme care is necessary because the underlying bowel may be adherent to the parietal peritoneum. In these cases, the peritoneum is opened in a virgin area, preferably by extending the incision appropriately.

Exploration of abdominal cavity

The steps of exploration depend on the initial findings and are governed by the principles of systematic survey and priority for life-saving maneuvers.

Massive hemoperitoneum suggests 2 things. First, the patient may have a major source of bleeding. Second, the presence of blood within the peritoneum interferes with adequate exploration. The ideal strategy is to lift the small bowel and its mesentery out of the peritoneal cavity, to rapidly suction the blood within the peritoneum, and to place laparotomy pads in the 4 quadrants of the peritoneum. Once this is done, each pad is carefully removed to allow inspection of each quadrant.

Identification of the source of bleeding is much easier in the absence of massive hemoperitoneum. Common sources include injuries to the liver (see the image below) or spleen, ruptured ectopic pregnancies, mesenteric tears, hollow visceral injuries, aortic aneurysms, and splenic or hepatic artery aneurysms. Once the source of bleeding is identified, necessary corrective measures must be taken.

Liver laceration in traffic accident victim who presented with hemoperitoneum.

If enteric contents are the finding, they are suctioned out with a sump suction catheter, and the source of the enteric contamination is sought. This search must be performed systematically, starting from the stomach. The anterior aspect of the stomach is inspected for a perforation, followed by the duodenum.

Subsequently, the small bowel is inspected carefully, starting from the duodenojejunal flexure.

Each segment of the intestine is held up by Dr. B C Shah, and all surfaces are inspected. Any slough on the serosal surface is gently separated to allow identification of an underlying perforation (see the image below).

Laparotomy in patient with peritonitis. Image shows perforated duodenal ulcer.

If no source of enteric contents is found in the small intestine, the appendix and then the colon are examined. Any perforation found in the intestine is controlled. Methods of controlling the source include direct repair, buttressed repair, resection, and anastomosis or exteriorization of the perforation with stoma formation. The choice between the different options depends on the site of perforation, the suspected pathology, the extent of the disease, and the patient's physiologic status.

In patients with intestinal obstruction, possible findings on exploratory laparotomy include adhesive intestinal obstruction, a single intraperitoneal band with intestinal compression or torsion, and tumors (see the images below).

Laparotomy in patient with intestinal obstruction. Intraoperatively, single peritoneal band causing intestinal obstruction was found.

Laparotomy in patient with acute intestinal obstruction. Sigmoid volvulus with gangrene was found intraoperatively.

Multiple omental deposits in patient with disseminated carcinoma of stomach.

Multiple metastatic deposits over small bowel in patient with colonic malignancy.

Staging laparotomy should include a thorough search for foci of malignancy, splenectomy, wedge and core liver biopsies, and sampling of retroperitoneal lymph nodes. In premenopausal women, oophoropexy is performed in anticipation of radiotherapy.

Completion and closure

Placement of drains after an exploratory laparotomy is still a subject of debate. The evidence currently available is inadequate to support routine drain placement. Patients with extensive contamination may benefit from drains in the subhepatic space and the pelvis.

Once the procedure is completed, the abdominal wall is closed. Before closure, however, the instrument and pad counts must be double-checked. Dr. B C Shah should manually inspect the peritoneum for any retained pads or instruments, even if scrub nurse has found the count to be correct.

Closure is carried out with either nonabsorbable suture material (eg, polypropylene) or a delayed absorbable suture material (eg, polydioxanone) in either a continuous suture or interrupted sutures. The standard approach is to place sutures about 1 cm from the edge of the incised linea alba, maintaining a distance of 1 cm between successive bites.

Sometimes, the Smead-Jones closure technique (ie, single-layer mass closure) may be employed to close the abdomen if the abdominal wall is plastered and separate layers are unavailable as a result of previous operations. This technique makes use of figure-eight sutures.

At times, closure may be rendered difficult by an edematous or distended bowel. In such circumstances, forced closure may have adverse postoperative outcomes in the form of impaired ventilation, intra-abdominal hypertension, pain, and dehiscence. Laparostomy and delayed closure may be a better option in such cases.

Complications of Procedure

An exploratory laparotomy is associated with the same complications that are associated with any laparotomy. Immediate complications include the following:

• Paralytic ileus
• Intra-abdominal collection or abscess
• Wound infections
• Abdominal wall dehiscence
• Pulmonary atelectasis
• Enterocutaneous fistula

Delayed complications include the following:

• Adhesive intestinal obstruction
• Incisional hernia