The Role of Laparoscopy/Thoracoscopy in Acute Care Surgery
Physiology of Laparoscopy
Laparoscopy in Emergency General Surgery
Laparoscopy in Trauma
Thoracoscopy in Acute Care Surgery
Laparoscopy and Thoracoscopy in Pediatric Acute Care Surgery
Minimally invasive approaches to the diagnosis and treatment of surgical conditions have been evolving over the past few decades. Whilst these approaches have become standard of care for a multitude of elective operations, their indications and usage are expanding in the emergency setting. Many conditions within the realm of acute care surgery are being approached by laparoscopy or thoracoscopy. The interface between this disruptive technology and optimum patient care often contests surgical dogma and there are a number of factors that make minimally invasive approaches in the acute care setting a challenge. In this chapter, we discuss the use of laparoscopy and thoracoscopy in acute care surgery. We will discuss the indications, advantages, and risks. We also provide evidence with respect to its safety, outcomes and costs.
Physiology of Laparoscopy
The physiological changes that accompany laparoscopy are due to the physical effects of the pneumoperitoneum as well as diffusion of Co2 used into the circulation. These systemic physiologic changes have implications for selection of patients for laparoscopy, as the patient must be able to tolerate them.
The induction of pneumoperitoneum leads to a rise in intra-abdominal pressure (IAP). Increased IAP can potentially reduce venous return to the heart, leading to diminution of preload and cardiac output. The cardiovascular system compensates by increasing the heart rate, systemic vascular resistance and mean arterial pressure [1-3]. These changes are generally tolerated by healthy patients but can represent significant problems in those with pre-existing cardiac diseases such as ischemic heart disease, valvular heart disease, and cardiac arrhythmias . Similar problems may arise in trauma and acute care surgical patients who may present with deranged physiology.
Displacement of the diaphragm superiorly during pneumoperitoneum induces a number of changes in respiratory mechanics. These include increased peak inspiratory pressure, increased respiratory rate, decreased respiratory compliance, and decreased tidal volume . These changes are generally well tolerated in the healthy patient but not so well in those with pre-existing pulmonary disease. Diffusion of carbon dioxide used for insufflation into the circulation may result in respiratory acidosis in patients with cardiopulmonary insufficiency .
The increased intra-abdominal pressure from pneumoperitoneum may lead to a decrease in renal blood flow . The subsequent activation of the rennin-angiotensin-aldosterone system clinically manifests as oliguria. This generally resolves with desufflation .
Portal venous flow may be decreased during pneumoperitoneum, resulting in hepatic hypoperfusion and transient elevation of liver enzymes . With this in mind, it is important during laparoscopy to minimize the use of anesthetic agents that are hepatotoxic. 
Laparoscopy in Emergency General Surgery (EGS)
Historical perspectives and evolution of laparoscopy in EGS
Since the early 1900s, there were multiple attempts by pioneer surgeons to use a camera to “look into the abdomen” . These early attempts at laparoscopy were mainly for diagnostic purposes, but gradually shifted to therapeutic uses as well in fields like gynecology . Once laparoscopy was shown to be safe and effective for common general surgical procedures such as cholecystectomy and appendectomy, their adoption into every day general surgical practice blossomed. Today, the indications for laparoscopy in general and acute care surgery continue to expand and this trend will likely continue into the future. The demand for minimally invasive surgery will continue to increase, chiefly because of the advantages it offers over traditional open surgery.
Advantages of laparoscopy over laparotomy in emergency general surgery
Majority of the advantages of laparoscopy stem from the small incisions and minimal dissections required to access the organ of interest. Laparoscopy avoids the morbidity of a laparotomy incision. The subsequent dissection tends to be focused, resulting in less tissue damage. This contributes to less postoperative pain and analgesic requirements.
Laparoscopy is also associated with lower rates of wound complications such as surgical site infections, wound dehiscence, and incisional hernias . Patients who have had laparoscopic surgery demonstrate earlier return to work and physical activities. Length of hospital stay is also shortened and overall hospitalization costs are lower, largely due to the decreased duration of hospitalization and need for narcotic pain medications. Cosmesis is also improved compared to laparotomy and overall patient satisfaction is higher. Advantages of laparoscopy over laparotomy for specific surgical indications are detailed in subsequent sections of this chapter.
Contraindications to use of laparoscopy in EGS
The contraindications to laparoscopy keep evolving and many previously absolute contraindications are now relative, while previously relative contraindications are no longer considered as such. For example, morbid obesity and pregnancy used to be considered contraindications to laparoscopy. These views have now been debunked, as bariatric surgical procedures are almost exclusively performed laparoscopically and obesity is no longer a deterrent to other minimally invasive procedures. Also, laparoscopic cholecystectomy and appendectomy are now safely performed during pregnancy when once they were contraindicated.
Contraindications to laparoscopy in the practice of emergency surgery include an inability to tolerated pneumoperitoneum, shock, uncorrectable coagulopathy, uncorrectable hypercapnia, clinical suspicion of abdominal compartment syndrome, abdominal wall infections, and extensive previous abdominal surgery with multiple scars .
Specific use of laparoscopy in EGS
Inflammatory conditions (appendicitis, cholecystitis, diverticulitis)
Acute abdominal pain is one of the most frequent reasons for presentation to the emergency room and the surgeon is frequently consulted to help either resolve the diagnosis or provide surgical care when a surgically correctable problem is identified. Inflammatory conditions such as acute appendicitis, acute cholecystitis and acute diverticulitis are leading causes of the acute surgical abdomen and can result in diffuse peritonitis, gangrene, perforation, sepsis, increased morbidity and mortality if there is a delay in diagnosis and treatment.
Acute appendicitis is second only to “non-specific abdominal pain” as the leading cause of the acute abdomen and is one of the most frequent acute surgical emergencies . Data from the Nationwide Inpatient Sample showed that in 2009, there were 207, 345 discharges with a principal diagnosis of acute appendicitis, with total hospital days of 362,000 and aggregate cost of $1,491,402,000 . It is estimated that in the United States, approximately 280,000 appendectomies are performed each year [13, 14]
The surgical treatment of acute appendicitis has a long, storied history and predated the antibiotic era. Ever since French-born surgeon Claudius Amyand successfully performed the first appendectomy [15, 16] and understanding of the disease process became clearer, open appendectomy was the treatment of choice for acute appendicitis for over 250 years. With the performance of the first laparoscopic appendectomy by Kurt Semm in the early1980s , laparoscopy rapidly became a safe and viable alternative to the open approach. Since then, multiple studies have compared the two techniques in a bid to decide which should be standard of care.
Martin et al.  compared demographically similar patients who underwent laparoscopic appendectomy (LA) or open appendectomy (OA) in a prospective randomized fashion. There were no differences in the rates of post-operative complications, time to return to work or physical activity, or hospital cost between the groups. Laparoscopic appendectomy was associated with a shorter hospital length of stay (2.2 vs. 4.3 days, p=0.007) but with a longer operative time (102.2 vs. 81.7 minutes, p<0.01). For patients who had a perforated appendix, the length of stay (1.5 vs. 9.5 days, p<0.01) and duration of antibiotics (1.3 vs. 7.3 days, p<0.01) were significantly shorter after laparoscopic appendectomy compared to open. Long et al.  performed a well-powered prospective randomized controlled trial in which 198 patients pre-operatively diagnosed with acute appendicitis were randomized to receive either laparoscopic or open appendectomy. In that study, laparoscopic appendectomy was associated with earlier return to a regular diet (1.6 vs. 2.3 days, p<0.01), fewer days on parenteral analgesics (1.6 vs. 2.2 days, p<0.01), lower morphine-equivalent dose of parenteral narcotics (14 mg vs. 34 mg, p=0.001), shorter postoperative hospital days (2.6 vs. 3.4 days, p<0.01) and quicker return to physical activity (14 vs. 21 days p <0.02). As in the study by Martin et al. (12), operative time was longer for the laparoscopic group (107 vs. 91 minutes, p<0.01). The two groups had similar billed charges ($7711 vs. $7146) and direct costs ($5357 vs. $4945), but the laparoscopic group had lower total hospital costs ($11,577 vs. $13,965).
Pedersen et al , in an RCT of 583 patients showed that LA was associated with shorter time to return to normal activity, faster return to work, lower wound infection rate, and improved cosmesis compared to the open approach. The operative time was longer for the laparoscopic approach (60 minutes vs. 40 minutes) but length of hospital stay was similar between the groups.
In an RCT from Europe, Mantoglu et al  randomized 63 patients into laparoscopic vs. open appendectomy. They showed similar rates of wound infection, abscess formation and postoperative C-reactive protein levels between the two groups, but less post-operative pain and earlier return to normal activities for the laparoscopic group. The cost of the procedure was higher for the laparoscopic compared to the open group. Thomson et al  demonstrated the safety of laparoscopic appendectomy for complicated appendicitis in a randomized controlled trial in which 114 patients were prospectively randomized to either the laparoscopic or open approach. They showed no difference in operative duration, rate of wound sepsis, rate of re-operation, length of hospital stay or re-admission rates between the two groups.
In terms of results, the randomized controlled trials that have compared LA to OA seem to fall into two groups. The earlier studies tended to show equivalent clinical outcomes for both methods, with slightly higher operative times and costs for LA. The more recent studies, in general, showed lower complication rates, shorter length of hospital stay, earlier return to work or physical activities, equivalent operative times, and lower total hospital costs for LA. This dichotomy of results appeared to be related to the learning curve for laparoscopy as well as the availability of the technique. As laparoscopy became an inherent part of the general surgery residency curriculum, along with significant technological advances in terms of development of appropriate laparoscopic equipment, there has been an overall improvement of surgeon skills and clinical outcomes for laparoscopic procedures in general [23, 24].
When randomized controlled trials produce conflicting results, meta-analyses become particularly useful in pooling studies together and giving a clearer picture of the clinical problem. Dai and Shuai , in a meta-analysis of 33 studies conducted between January 1992 and March 2016 compared 1810 patients who underwent LA with 1832 patients who had OA. They showed that in adult patients, LA was associated with lower rates of wound infection, less postoperative complications, lower postoperative length of stay, and quicker return to normal activity. Although LA was associated with a longer operative time, the incidence of intra-abdominal abscess and re-operation between the two groups was similar. Wei et al. , in a meta-analysis of 25 RCTs with 4,694 patients (LA: 2,220; OA: 2,474), showed that LA patients had a lower rate of post-operative complications, earlier start of diet, shorter hospital length of stay, and earlier return to work or normal physical activity compared to OA. LA had a longer operative time than OA, but the overall hospital cost was similar. Findings from these two meta-analyses have been corroborated by others [27, 28].
The question of superiority of one approach for appendectomy over the other in patients with obesity has been an intensely studied topic in the surgical field, although there are hardly any randomized controlled studies specifically designed with obese patients as the population of interest. Clarke et al.  did a subset analysis of morbidly obese patients in a randomized controlled study comparing laparoscopic vs. open appendectomy. Of 37 patients with a BMI > 30 kg/m2, 23 patients had laparoscopic appendectomy while 14 had open appendectomy. The study found no differences in complication rates, duration of hospital stay, narcotic requirements, time to resumption of diet, and quality of life between the two groups. The authors concluded that laparoscopic appendectomy did not show a benefit over the open approach in obese patients diagnosed with appendicitis. This study has several important limitations that are also seen in many of the other RCTs that we have examined. Obese patients were not the primary population of interest and represent a subset analysis of a randomized controlled study. Also, the sample sizes are small, suggesting the possibility of an underpowered study prone to a type II error. In an analysis of data from the Nationwide Inpatient Sample, Masoomi et al.  studied 42,426 obese patients who underwent an appendectomy between 2006 and 2008. In those with a non-perforated appendix, laparoscopic appendectomy showed a lower overall complication rate (7.17% vs. 11.72%, p<0.01), mortality (0.09% vs. 0.23%, p<0.01), hospital charges ($25,193 vs. $26,380, p=0.04) and length of hospital stay (2.0 vs. 3.1 days, p<0.01). The findings were also similar for obese patients with perforated appendix, with the laparoscopic approach demonstrating a superior outcome. Mason et al.  corroborated these findings using data from the American College of Surgeons National Surgical Quality Improvement (NSQIP) Program database. In a sample of 13, 330 obese patients with a body mass index >=30 kg/m2 who underwent appendectomy between 2005 and 2009, they showed that laparoscopic appendectomy was associated with a 57% reduction in overall morbidity in all obese patients, and a 53% morbidity reduction after a 1:1 matching to reduce bias. After matching, laparoscopic appendectomy showed a reduction in length of stay by 1.2 days compared to open.
A review of the NSQIP database by Tuggle et al.  comparing LA versus OA for complicated appendicitis showed that superficial surgical site was 70% less likely and wound dehiscence was 78% less likely to occur with LA. The likelihood of organ space infection occurring was two-fold more likely with laparoscopy. LA was also associated with a shorter length of hospital stay.
In summary, laparoscopic appendectomy confers tangible clinical advantages over open appendectomy at equivalent costs for both complicated and uncomplicated appendicitis and has become the standard of care. The open technique is still a valuable skill set in the armamentarium of the modern day acute care surgeon and should be employed without hesitation when there are contraindications to the laparoscopic approach.
Acute cholecystitis and other gallstone-related complications
The first laparoscopic cholecystectomy (LC) was performed by German Surgeon Erich Mühe on September 12, 1985 . Prior to that, open cholecystectomy (OC) was the procedure of choice for surgical management of symptomatic cholelithiasis and other acute gallbladder pathologies. With increasing availability of laparoscopic cholecystectomy, several randomized controlled trials were carried out to compare the two approaches. Unlike the case of laparoscopic versus open appendectomy where the early results were conflicting, the case for laparoscopic cholecystectomy to become the standard of care was quickly unequivocal.
Kiviluoto et al.  randomized 63 patients with acute cholecystitis and similar demographic, physical and clinical characteristic to receive either LC or OC. They found a significantly lower postoperative complication rate, shorter postoperative hospital stay and lower mean length of stay in the LC group. El-Awadi et al. , in a randomized controlled study, evaluated 110 cirrhotic patients with symptomatic cholelithiasis. They demonstrated a longer operative time (96.13 vs. 76.13 minutes, p<0.05), higher rate of intra-operative bleeding necessitating blood transfusion, longer time to resume diet (47.84 vs. 18.36 hours, p<0.005), longer length of hospital stay (6.00 vs. 1.87 days, p<0.01) and higher postoperative morbidity in the OC group compared to LC. Ji et al. performed an RCT in 80 patients with symptomatic gallbladder disease and portal hypertension from cirrhosis in a bid to compare LC vs. OC. LC demonstrated superior outcomes over OC with lower intra-operative blood loss, shorter time to resume diet, fewer post-operative complications and shorter length of hospital stay.
In terms of costs, multiple studies have demonstrated a net cost-effectiveness profile that favors laparoscopic cholecystectomy, with some others showing equivalent costs. While initial studies demonstrated a higher operating room costs for LC, these were offset by lower overall hospital costs due to shorter hospital length of stay. McIntyre et al.  reported a mean hospital charge of $6471 for LC vs. $8896 for OC.
As with laparoscopic appendectomy, there are still clear indications for open cholecystectomy. These include failure to safely gain access to induce pneumoperitoneum, failure to progress during a laparoscopic cholecystectomy, failure to visualize the cystic duct laparoscopically despite significant time spent on dissection, inability of the patient to tolerate pneumoperitoneum, bleeding, and hemodynamic instability. In these cases, there should be no hesitation to either employ the open approach ab initio or convert to the open method. The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) recommends open cholecystectomy for patients with selective gallbladder mucosal calcifications . While laparoscopic cholecystectomy is curative for gallbladder cancers limited to the mucosa, i.e. T1a, higher stages required more extensive resections via the open technique .
Laparoscopic cholecystectomy is the standard of care for surgical removal of the patients with acute cholecystitis, symptomatic cholelithiasis, biliary dyskinesia, gallstone pancreatitis, and gallbladder polyps. It is safe, effective, and is associated with lower overall costs. However, the open approach should be employed if there is a contraindication to laparoscopy
Acute diverticulitis is one of the most common diseases accounting for hospital visitations in the United States. In 2009, diverticulitis without hemorrhage was the 3rd most common discharge diagnosis among all patients with a principal gastrointestinal or hepatologic disease, accounting for 1,099,000 total hospital days and an aggregate cost of $2,115,989,000 . It is estimated that 2.5 million people in the U.S. are affected by diverticulitis .
While multiple classification systems exist, the Hinchey classification or its various modifications still have widespread utility worldwide and helps to stratify patients for appropriate operative or non-operative management . In general, stage I diverticulitis can be managed non-operatively with bowel rest and antibiotics, while stage II with large abscesses are managed with CT-guided percutaneous drainage and antibiotics, either as primary therapy or as a bridge to elective colonic resection [40, 41]. Stages III and IV typically present with an acute abdomen and require emergent or urgent surgical intervention. At any time, the surgical procedure performed for diverticulitis and its timing depends on whether it is uncomplicated or complicated, the latter referring to diverticulitis with free perforation, large intra-abdominal or pelvic abscesses, obstruction, fistula, or stricture .
The American Society of Colon and Rectal Surgeons (ASCRS), in their 2014 clinical practice guidelines for the treatment of sigmoid diverticulitis, recommend individualizing the decision to offer elective sigmoid colectomy following recovery from uncomplicated acute diverticulitis . They also made a strong recommendation for considering elective sigmoid colectomy after recovery from an episode of complicated acute diverticulitis. In the elective setting, surgical treatment after resolution of acute uncomplicated diverticulitis general involves resection of the sigmoid colon . Historically, open sigmoid colectomy with colorectal anastomosis or creation of ostomy has been the procedure of choice for elective surgical management of diverticulitis. With the advent of laparoscopy, laparoscopic sigmoid colectomy is being increasingly used in this clinical scenario and multiple studies have been done to see if patients derive the laparoscopic advantages. Klarenbeek et al.  performed a multi-center, randomized controlled trial in which 104 patients with symptomatic sigmoid diverticulitis with comparable age, gender, body mass index, comorbidities, American Society of Anesthesiologists (ASA) class, history of previous abdominal surgery and indications for colectomy were assigned to undergo either laparoscopic sigmoid resection or open sigmoid resection. Initial short-term results from this “Sigma Trial” showed that the laparoscopic group had a 15.4% reduction in the rate of major complications, less postoperative pain, shorter hospital stay, and higher quality of life scores compared to the open sigmoid colectomy group. However, the laparoscopic approach took longer to perform but was associated with a lower estimated blood loss. Follow up results from the Sigma Trial showed equivalent late clinical outcomes between open and laparoscopic sigmoid colectomies between 30 days and 6 months post-surgery . Overall, there was a 27% reduction in total (early plus late) postoperative morbidity after the laparoscopic approach. Gervaz et al.  randomized 113 patients scheduled for elective sigmoid colectomy for diverticulitis to receive either a laparoscopic or an open approach. The laparoscopic group had earlier return of bowel function and shorter hospital stay compared to the open colectomy group.
The findings from these randomized controlled trials were corroborated by Masooni et al  who examined data from the Nationwide Inpatient Sample in which they compared the laparoscopic versus the open approach in 124, 734 patients requiring elective surgery for diverticulitis. The open group had a higher intra-operative complication rate as well as a higher incidence of all postoperative complications including ileus, bowel obstruction, leak, wound infection, abdominal abscess, pneumonia, urinary tract infection, respiratory failure and venous thromboembolism. Hospital length of stay, mortality and total hospital charges were also higher in the open group. A review of the NSQIP database showed that compared to open colectomy, laparoscopic colectomy with primary anastomosis for diverticulitis was associated with decreased postoperative morbidity . Other investigators have also demonstrated the cost-effectiveness of laparoscopic sigmoid colectomy for diverticular disease . In light of the available evidence, the American Society of Colon and Rectal Surgeons recommend the laparoscopic approach for elective sigmoid colectomy over the open technique when expertise for the former is available .
For complicated diverticulitis, there is ample support for laparoscopic colectomy, albeit mostly from non-randomized studies. Jones et al  demonstrated the safety and effectiveness of laparoscopy for complicated diverticular disease. They examined data on 500 patients who had laparoscopic resection of complicated and uncomplicated diverticular disease and found no significant difference in operating time, conversion to open technique, duration of hospital stay, morbidity, and mortality between the two groups. A separate study comparing laparoscopic sigmoid resections for recurrent diverticulitis versus complicated diverticulitis showed longer operative time, higher intra-operative blood loss, and longer hospital length of stay for the complicated group, but no difference in conversion rates, operative complications, or major postoperative complications between the groups . Laparoscopic colectomy for complicated diverticulitis is technically more challenging, and whether it is applied or not depends to a large extent on the experience of the surgeon and the condition of the patient .
The use of laparoscopy for surgical management of diverticulitis continues to evolve and recently, laparoscopic lavage is being examined as either a bridge to elective colonic resection or as primary therapy in patients with Hinchey classes III diverticulitis.
The DILALA trial [“Diverticulitis – LAparoscopic LAvage vs resection (Hartman procedure) for acute diverticulitis with peritonitis” (DILALA)] randomized 83 patients with laparoscopically confirmed perforated diverticulitis with purulent peritonitis to receive either laparoscopic lavage or open Hartmann’s procedure . The results showed no significant difference in morbidity and mortality between the two procedures. However, laparoscopic lavage was associated with shorter operative time, stay in the recovery unit and hospital length of stay. After a median follow up of 372 days for the laparoscopic lavage group and 378 days for the Hartmann group, the reoperation rate within 12 months was 27.9% for patients in the laparoscopic lavage group compared to 62.5% for the Hartmann group. There was no difference in mortality or severe adverse events between groups . Three patients in the lavage group and 11 patients in the Hartmann group had a stoma after 12 months of follow up. The authors suggested that laparoscopic lavage could be a primary treatment modality for Hinchey III diverticulitis.
The SCANDIV trial, examining the same question, concluded that laparoscopic lavage did not reduce severe post-operative complications and was associated with worse secondary outcomes . However, this study had a major methodological flaw, in that patients were randomized before their Hinchey stage was determined, leading to the potential inclusion of stages other than Hinchey III . The LADIES trial also examined a similar research question, with patients only randomized after they were confirmed to have Hinchey class III on initial diagnostic laparoscopy . However, the laparoscopic lavage arm was prematurely terminated due to safety concerns.
A recent meta-analysis of these three studies showed that laparoscopic lavage was associated with fewer re-operations, but with no difference in morbidity and mortality between the groups . Cost analyses of both the LADIES and the DILALA trials favor laparoscopic lavage [57, 58]. Additional randomized controlled trials with well defined patient populations and unequivocal results will need to be done before laparoscopic lavage can be considered as first line recommendation.
Perforated peptic ulcer
The recognition of the role of Helicobacter pylori in the pathogenesis of peptic ulcer disease (PUD) and the introduction of effective triple therapy regimens have fundamentally modified the role of surgery in the management of this disease . Surgery is now mostly indicated for complications of PUD, including perforation, bleeding or obstruction. With few exceptions, perforated peptic ulcer (PPU) typically presents as an acute abdomen and is a condition the acute care surgeon will be commonly called upon to manage. Approximately 4 million people worldwide are affected by peptic ulcer disease, with 2-14% of these cases progressing to perforation . Of the common indications for surgery in patients with peptic ulcer disease, perforation has the highest mortality accounting for up to 40% of all deaths  and a morbidity of about 50% .
Since Roscoe Reid Graham in 1937 described the omental patch repair of perforated peptic ulcer, the technique has been modified and is now extensively employed in current day surgical management of perforated peptic ulcer. Given the success of the omental patch repair when coupled with effective anti-H pylori medications, there has been a reduced indication for more extensive anti-ulcer operations . Perforated PUD is now most commonly treated by omental patch repair followed by triple therapy for H. pylori, unless there are compelling indications to perform a more extensive acid-reducing procedure.
Laparoscopic omental patch repair has emerged as a safe, effective, and cost-effective alternative. Siu et al.  randomized 130 patients clinically diagnosed with perforated peptic ulcer to receive either laparoscopic or open omental patch repair with peritoneal lavage. The two groups were comparable in terms of age, gender, site and size of perforations, and ASA class. They showed that laparoscopic omental patch repair was associated with shorter operative time, less postoperative pain and requirement for analgesics, fewer pulmonary complications, shorter hospitalization days and earlier return to normal activities compared to the open approach. Another recently published randomized controlled study assigned 119 patients into laparoscopic or open repair of perforated peptic ulcers . In this study, the two approaches demonstrated comparable operative duration, postoperative complications, and total hospital costs. However, the laparoscopic group had a shorter hospital length of stay and less postoperative pain. The LAMA trial, a multi-center, randomized controlled study of laparoscopic versus open repair of PPU showed a significantly longer operating time and more postoperative pain in the open group . However, complications and hospital length of stay were comparable between the two groups. Overall, current evidence supports the laparoscopic omental patch repair as a safe, effective and cost-effective management strategy for perforated peptic ulcer with distinct advantages over the open approach [66-69].
Internal hernia after laparoscopic Roux-en-y gastric bypass
For patients with morbid obesity and its associated co-morbidities, bariatric surgical procedures represent the most effective and consistent means of sustainable weight loss and resolution of these co-morbidities . Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy are two of the most commonly performed bariatric procedures. However, LRYGB has its unique acute surgical complications. One of the most feared complications of this procedure is the development of internal hernia. With an incidence ranging from 0.2 to 8.6%, internal hernia occurs when a loop of bowel herniates through any of three potential mesenteric defects : between the Roux limb and the transverse mesocolon (Peterson’s defect), between biliopancreatic limb and Roux limb at the jejunojenunostomy, and in the transverse mesocolon after a retrocolic approach. This can result in small bowel obstruction and twisting of the bowel mesentery leading to bowel ischemia, gangrene and perforation .
Patients with internal hernia may present with either non-specific symptoms or those suggestive of small bowel obstruction: intermittent colicky abdominal pain, nausea, vomiting, and bloating . Physical examination may reveal abdominal tenderness, or may be benign. The diagnosis may be missed on CT scan of the abdomen, given its variable sensitivity . Recent studies have identified certain CT scan findings that appear to be accurate pointers to the presence of an internal hernia. These include “swirled appearance of mesenteric fat or vessels, mushroom shape of hernia, tubular distal mesenteric fat surrounded by bowel loops, small-bowel obstruction, clustered loops of small bowel, small bowel other than duodenum posterior to the superior mesenteric artery, and right-sided location of the distal jejunal anastomosis”  Mesenteric swirling or the “swirl sign”, has a sensitivity and specificity of 86-89% and 86-90% is the most consistent radiologic predictor of internal herniation . The CT scan may not show any abnormalities in about 26% of patients .
In patients who have had LRYGB and present with intermittent abdominal pain, a diagnostic laparoscopy to rule out internal hernia, even in the absence of suggestive CT scan findings is recommended . Delay in diagnosis and treatment can be fatal. The diagnosis can be confirmed during laparoscopy and reduction of the hernia performed. Closure of the mesenteric defect after reduction of the hernia is recommended .
Incarcerated and strangulated abdominal wall hernias
Abdominal wall hernias include ventral (epigastric, umbilical, Spigelian, incisional, lumbar) and groin (inguinal and femoral) hernias . The majority of these hernias are repaired electively. However, in the setting of incarceration or strangulation, urgent or emergent repair is indicated.
In the elective setting, laparoscopy has found increased use in repair of all types of abdominal wall hernias, with preservation of the laparoscopic advantages including less postoperative pain, earlier return to normal activities and lower rates of surgical site infections. Overall recurrence rates appear to be equivalent between the laparoscopic and open approaches [78, 79].
While there are multiple randomized controlled studies that demonstrate superior outcomes of laparoscopic abdominal wall hernia repair compared to the open technique, the majority of these studies included mainly elective cases. The data on laparoscopic herniorraphy for incarcerated and strangulated abdominal wall hernias are derived from retrospective analyses. Several retrospective studies have established the safety and effectiveness of laparoscopic repair of incarcerated ventral or incisional hernias with low complication rates and recurrence rates comparable to the open approach [80-82]. Laparoscopic repair has also been safely and effectively used for incarcerated and strangulated inguinal hernias [83-85], including bowel resection where indicated. Yang et al. , examined data on 188 patients with strangulated groin hernias who underwent either laparoscopic repair (n=57) or open repair (n=131). The mean operative times were similar between the groups. The laparoscopic group had a lower wound infection rate and hospital length of stay. The open repair group had a laparotomy rate of 14.5% compared to zero in the laparoscopic repair group. The authors concluded that laparoscopic repair was feasible for strangulated groin hernias and was associated with lower morbidity. Thus, laparoscopic repair of abdominal wall hernias in the acute setting appears safe and effective. In view of the strength of current evidence, we suggest that the laparoscopic approach should be considered for complicated abdominal wall hernias.
Laparoscopic-assisted intra-abdominal foreign body removal
Foreign body ingestion is predominantly a pediatric problem but can also occur in adults for a variety of reasons. The majority of gastrointestinal foreign bodies will pass spontaneously after ingestion. However, depending on size and configuration, some can be entrapped in the stomach or small bowel, especially at the gastro-esophageal junction, pylorus, ileocecal valve and rectosigmoid junction . Such trapped foreign bodies may cause obstruction or perforation of the gut and should be removed.
Upper gastrointestinal endoscopy (esophagogastroduodenoscopy, EGD) is the procedure of choice for removal of foreign bodies in the stomach. However, in certain clinical scenarios, laparoscopy can be used to facilitate the removal of gastric foreign bodies. These include failure of endoscopic therapy, perforation, or obstruction . These gastric foreign bodies can be removed by performing laparoscopic gastrotomy, retrieval of the foreign body and intracorporeal suture repair of the gastrotomy . In practice, this surgical retrieval can be performed through either a laparotomy or laparoscopy. The advantages of the laparoscopic approach include smaller incisions, less postoperative pain and earlier return to normal physical activity . Laparoscopic removal of intra-gastric foreign bodies can be facilitated by endoscopic assistance [90, 91].
Laparoscopy can also be employed in lieu of laparotomy for removal of retained small intestinal foreign bodies [87, 92]. This involves a laparoscopic enterotomy, extraction of the foreign body, and intracorporeal suturing of the enterotomy. If there is significant damage to the bowel such that primary repair would be tenuous, then resection of the damaged segment followed by anastomosis can be performed. If the foreign body exits the lumen and makes its way into the peritoneal cavity, laparoscopic retrieval can be performed as well, with careful search for the perforated viscus and primary repair [93, 94]. Again, the minimal invasive nature of laparoscopy with less postoperative pain and earlier return to work and normal physical activities makes it an attractive approach compared to laparotomy for this indication .
Adhesive small bowel obstruction
The initial management of uncomplicated small bowel obstruction remains non-operative, with bowel rest, nasogastric tube suction and intravenous fluid resuscitation as the cornerstone of that approach. The majority of cases will resolve. Failure of resolution of small bowel obstruction or the development of peritoneal signs mandates surgical exploration. Since most cases of small bowel obstruction are due to adhesions from previous abdominal surgery, the classic surgical approach is exploratory laparotomy and lysis of adhesions, plus or minus enterectomy and anastomosis. With the advent of minimally invasive surgery, laparoscopy is being used increasingly for surgical management of small bowel obstruction. There is no published randomized controlled trial with results comparing laparoscopic versus open surgery for adhesive small bowel obstruction (ASBO). The results of an ongoing RCT for this purpose are set to be available in 2018 . However, several retrospective studies have demonstrated the safety and effectiveness of laparoscopy for ASBO in carefully selected patients and current recommendations on the use of laparoscopy in adhesive small bowel obstruction are based on the results of these studies.
Wang et al.  performed laparoscopic adhesiolysis in 46 patients with recurrent small bowel obstruction, with a mean postoperative follow-up of 46.5 months. Laparoscopic adhesiolysis was successfully completed in 91.3% of patients and 93.5% were asymptomatic postoperatively. Hackenberg et al.  used a propensity score matching analysis to compare patients who underwent laparoscopic versus open surgery for acute ASOB, adjusting for disparities between the two patient populations. They showed that laparoscopy was associated with a shorter hospital length of stay but a similar complications profile as the open approach. In a meta-analysis of four retrospective studies with a total of 334 patients, Li et al.  demonstrated an association between laparoscopic adhesiolysis and reduced overall complication rate, shorter duration of postoperative ileus, and less pulmonary complication rate compared to open surgery. There were no statistically significant differences in the rates of intra-operative bowel injuries, wound infection rates, or mortality.
One of the most recent clinical guidelines on laparoscopic management of small bowel obstruction comes from the World Society of Emergency Surgery ASOB working group, the “Bologna guidelines for diagnosis and management of adhesive small bowel obstruction” . These guidelines suggested that open surgery should be the preferred approach for cases of ASOB where there is strangulation and after failed conservative management, but that laparoscopy using the open access technique can be used in highly selected patients namely, patients with a first episode of small bowel obstruction or anticipated single adhesive band. They also suggested conversion to laparoscopic-assisted adhesiolysis or laparotomy for patients with dense or pelvic adhesions.
Potential benefits of laparoscopic adhesiolysis when compared to open adhesiolysis include reduced postoperative pain, lower rates of surgical site infection, earlier return to physical activities, shorter length of hospital stay and lower incidence of postoperative adhesion formation [99-101].
Thus, there is a role for laparoscopy in the surgical management of adhesive small bowel obstruction. This requires careful clinical judgment and patient selection as well as availability of laparoscopic expertise.
Large bowel obstruction
The use of minimally invasive techniques for large bowel obstruction depends on the etiology of the obstruction, degree of distension of the bowel, the patient’s hemodynamic status, presence or absence of strangulation, bowel ischemia, necrosis, perforation or peritonitis. In a hemodynamically unstable or septic patient with large bowel obstruction and a presumed abdominal source of sepsis, rapid access to the abdomen is best achieved through a laparotomy. In the more clinically stable patient, laparoscopy may have a role. There is a growing body of data to support the use of laparoscopy for the surgical management of large bowel obstruction due to diverticulitis, colonic malignancy and volvulus. Large bowel obstruction secondary to diverticular disease can be safely and effectively treated surgically with laparoscopic colon resection. The role of laparoscopy in the management of diverticulitis has been discussed in an earlier section of this chapter.
Laparoscopic colectomy is being routinely utilized to manage large bowel obstruction due to colonic malignancy. This typically follows fluid resuscitation, nasogastric decompression, antibiotic therapy, and in some cases placement of a colonic stent to relieve the obstruction . These options are consistent with the American Society of Colon and Rectal Surgeons’ Practice Parameters for The Management of Colon Cancers . The use of colonic stents as a bridge to surgical resection in obstructing colonic lesions has been shown to reduce morbidity and mortality rates when compared to urgent surgical intervention . Relief of colonic obstruction with stents may make laparoscopic resection much easier and safer. Cheung et al.  randomized 48 clinically matched patients with an obstructing left-sided colon cancer to receive either self-expanding endoluminal stenting followed by laparoscopic resection or emergency open surgery. The endolaparoscopic group had significantly lower estimated blood loss, post-operative pain, rate of anastomotic leak, and incidence of wound infection. There was more successful one-stage operation in the endolaparoscopic group compared to the open group (66.7% vs. 37.5%, p=0.04), and zero incidence of permanent ostomy in the endolaparoscopic group compared to 25% in the emergency open group (p=0.03). A similar randomized controlled study by Cui et al.  replicated these findings: patients with obstructing left-sided colon cancer who had self-expanding metal stents followed by laparoscopic colon resection had less intra-operative blood loss, lower rate of permanent stoma, less postoperative pain, lower rates of postoperative complications, and a higher rate of one-stage operation compared to those who underwent emergent open surgery. The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Guidelines for Laparoscopic Resection of Curable Colon and Rectal Cancer recommends that a right or extended right colectomy be performed for patients with an obstructing right or transverse colon cancer and that the choice of procedure be individualized for those with an obstructing left-sided colon cancer . The SAGES guidelines suggest that for the latter situation, colonic stenting may increase the likelihood of completing a one-stage procedure and reduce the chance of an end colostomy, consistent with the results of the two randomized controlled trials cited earlier.
The initial treatment of sigmoid volvulus in the absence of bowel ischemia or perforation is endoscopic decompression . Due to the high recurrence rate without surgery, endoscopic decompression is typically followed by elective sigmoid colectomy. This can be performed laparoscopically. There are retrospective studies describing the feasibility of laparoscopic colonic resection for sigmoid volvulus after endoscopic decompression [108-110]. Several head-to-head comparative studies between the laparoscopic and the open approach still need to be conducted.
Evaluation of non-specific abdominal pain
Non-specific abdominal pain (NSAP) is defined as “acute abdominal pain of less than 7 days duration where the diagnosis remains uncertain after baseline examination and diagnostic tests” . The theoretical advantages of using diagnostic laparoscopy (DL) to evaluate patients with non-specific abdominal pain include early identification and treatment of potentially serious intra-abdominal pathologies, prevention of treatment delay and its complications, and reducing the negative laparotomy rate . The literature provides conflicting results on the benefits of diagnostic laparoscopy for this purpose. Some studies show that early diagnostic laparoscopy increased diagnostic accuracy, improved quality of life and reduced length of hospital stay in patients with NSAP compared to active clinical observation [111-113], with others showing that DL failed to demonstrate any reduction in morbidity and mortality . The SAGES Guidelines for Diagnostic Laparoscopy suggests considering DL in patients without a clear diagnosis after appropriate clinical examination and radiologic studies and that when laparoscopic expertise is available, DL may be preferable to exploratory laparotomy in appropriately selected patients with an indication for surgery 
Laparoscopy in Trauma
Historical perspectives and evolution of laparoscopy in trauma
Although accounts vary, one of the earliest uses of laparoscopy in trauma was by Lamy and Sarles who, in 1956, described the use of “peritoneoscopy” for evaluation of two cases of splenic injury [114, 115]. Heselson in 1970 described the use of laparoscopy in 68 patients with penetrating or blunt trauma, laying out some criteria for laparotomy based on the laparoscopic findings [115, 116]. These early uses of laparoscopy in trauma seemed to have preceded the adoption of the minimally invasive technique in emergency general surgery. However, the adoption of laparoscopy for emergency general surgery has outpaced that in the trauma setting. Lim et al.  speculated that the complexity of laparoscopic suturing may act as a barrier to the adoption of minimally invasive surgery. In the trauma population, the unique physiologic derangements of injured patients and their inability to tolerate additional physiologic changes induced by pneumoperitoneum may represent further barriers. Careful selection of patients is essential to successful utilization of laparoscopy in trauma.
The high negative laparotomy rates, associated morbidities and costs following a laparotomy for trauma remain a source of concern for trauma surgeons and other stakeholders. In the 1980s, the negative laparotomy rates for penetrating abdominal trauma were as high as 30% for stab wounds, 16% for gunshot wounds, and 19% for blunt abdominal trauma . Over the last two decades, with improvements in trauma imaging and other technologies, there has been a significant reduction of the negative laparotomy rate to about 3.9%, depending on the experience of the trauma center . However, the complication rate after negative laparotomy still remains high, at about 14.5% as reported by Schnüriger et al. , 10.1% of which were related directly to the surgery. As a result, laparoscopy has emerged as a viable means of reducing this negative laparotomy rate and associated morbidities.
Successful use of laparoscopy for trauma requires competent intracorporeal suturing skills, ability to comfortably run the bowel, and overall comfort with the laparoscopic technique. Proper patient selection is also paramount.
Advantages of laparoscopy over laparotomy in trauma
One of the major advantages of laparoscopy over laparotomy for trauma is reduction of the negative laparotomy rate. Simon et al. showed that as the rate of laparoscopy after penetrating injury increased, there was a corresponding decrease in the negative laparotomy rate . Ahmed et al.  examined data on 52 patients who suffered stab or gunshot abdominal wounds, had stable vital signs, had no contraindications to laparoscopy, and met criteria for exploratory laparotomy. They showed that with prior diagnostic laparoscopy, exploratory laparotomy was avoided in 77% of patients. There was a reduction of hospitalization by 55%. They concluded that with well-defined conditions, laparoscopy for trauma was safe and effectively reduced non-therapeutic laparotomy.
Laparoscopy has also been shown to demonstrate the usual advantages of a minimally invasive technique in the trauma population. In a study where 38 abdominal trauma patients were matched 1 to 1 for age, gender, body mass index, ASA class, hemodynamic stability, and mechanism of injury, laparoscopy was associated with shorter operative time, lower intra-operative blood loss, earlier return to normal diet, and shorter length of hospital stay compared to exploratory laparotomy . Thirty-day mortality was similar between the two groups. Marks and co-authors  showed variable costs, total costs, and length of hospital stay were significantly lower in patients with penetrating abdominal or flank trauma who were hemodynamically stable and had no other injuries requiring emergent intervention if these patients underwent laparoscopy rather than laparotomy, with a net savings of $1,059 per laparoscopy performed. These and other studies demonstrate the safety, effectiveness and cost-effectiveness of trauma laparoscopy in carefully selected patients.
Contraindications to use of laparoscopy in trauma
Laparoscopy is contraindicated in trauma patients who are hemodynamically unstable. According to the SAGES Guidelines on Diagnostic Laparoscopy for Trauma, other contraindications for the use of laparoscopy in trauma include known intra-abdominal injuries and posterior penetrating trauma with a high chance of bowel injury, and limited laparoscopic skills . The latter are not necessarily absolute contraindications, as bowel injuries, depending on the extent, may be repaired successfully in stable patients via the laparoscopic approach.
Specific use of laparoscopy in trauma
Diagnostic indications in blunt and penetrating trauma
Evaluation of the diaphragm in thoracoabdominal trauma
Diagnostic laparoscopy is particularly useful for evaluation of blunt and penetrating trauma to the thoracoabdominal region. Radiologic imaging is notorious for its low sensitivity in detecting diaphragmatic injury from thoracoabdominal injuries. In a single series of 55 patients who suffered left-sided penetrating abdominal trauma, Mjoli et al.  showed that diaphragmatic injury was present in 40% of these patients and radiologic findings were unreliable in predicting the presence of diaphragmatic injury. In the patients with diaphragmatic injuries, these injuries were successfully repaired laparoscopically. McQuay and Britt  used diagnostic laparoscopy to evaluate 80 patients with penetrating thoracoabdominal injuries and found that 27.5% had a diaphragmatic injury. Importantly, diagnostic laparoscopy was negative in 72.5% of these patients, saving them an exploratory laparotomy. The patients who had diaphragmatic injuries on laparoscopy underwent a laparotomy to rule out associated intra-abdominal injury and 77.2% of this cohort had a positive exploration that required surgery. Murray et al.  corroborated these findings when they used laparoscopy to evaluate 110 hemodynamically stable patients with penetrating injuries to the lower chest and who had no indications for exploratory laparotomy. They found a diaphragmatic injury rate of 24%. Of note, these injuries produced no clinical or radiologic findings and would have been missed if laparoscopy was not performed. The authors suggested performing laparoscopy to rule out occult diaphragmatic injury in patients with penetrating injuries to the lower chest that have no other indications for laparotomy. Friese et al.  reported a specificity, sensitivity, and negative predictive value of 100%, 87.5%, and 96.8%, respectively for laparoscopy in ruling out occult diaphragmatic injury and concluded that laparoscopy was sufficient to exclude this injury in asymptomatic and hemodynamically normal patients.
Exclusion of intra-abdominal injuries
As part of its diagnostic use, laparoscopy can be used to exclude intra-abdominal injuries, with a view to lowering the negative laparotomy rate. Taner et al.  examined 28 patients with blunt abdominal trauma and 71 with penetrating abdominal trauma who underwent diagnostic laparoscopy prior to laparotomy. All patients were hemodynamically stable. They showed that the use of diagnostic laparoscopy reduced the rate of unnecessary laparotomies from 60.7% to 0 in the patients with blunt abdominal trauma and from 78.9% to 16.9% in those with penetrating abdominal trauma.
Evaluation of peritoneal violation following penetrating abdominal wounds
Laparoscopy is useful in evaluating patients with penetrating abdominal wounds if there is uncertainty about whether or not there is violation of the abdominal fascia. This is particular true for tangential abdominal gunshot or stab wounds and may reduce the negative laparotomy rate . In a prospective analysis of 182 patients who were hemodynamically stable and had equivocal evidence of intra-abdominal injury, Fabian et al.  found that in 55% of these patients, there was no peritoneal violation. Weinberg and colleagues  performed diagnostic laparoscopy under local anesthesia in the emergency room in 15 patients with equivocal evidence of penetrating abdominal wound and found no evidence of peritoneal violation in 73.3% of them, allowing early discharge and a cost savings of $2227 per patient with negative findings compared to performing the same procedure with similar results in the operating room. The SAGES guideline on diagnostic laparoscopy supports its use for this indication .
Diagnosis of bowel and mesenteric injuries
Diagnostic laparoscopy is effective for the diagnosis of small bowel injuries following penetrating abdominal trauma. Kawahara et al.  showed that the accuracy, sensitivity and specificity of laparoscopy for detection of small bowel injuries after penetrating abdominal trauma were 98.66%, 97.61%, and 100% respectively. In blunt abdominal trauma, the ability of laparoscopy to detect bowel injury has been shown to be just as high. Mathonnet et al  reported a sensitivity and specificity of 100% respectively, for the detection of blunt small bowel trauma when laparoscopy was performed, compared to 83.3% and 22.2% respectively, for abdominal CT scan.
Therapeutic indications in blunt and penetrating trauma
The indications for laparoscopy in trauma have expanded beyond just diagnosis to include therapy for specific injuries. Zafar et al  examined the National Trauma Data Bank (NTDB) datasets 2007-2010, identifying 4755 patients who underwent a diagnostic laparoscopy at 467 trauma centers. Of these patients, 19.3% underwent therapeutic laparoscopy, including diaphragmatic repair, bowel resection or repair, and splenectomy. Laparoscopy in this study was associated with a reduced length of hospital stay. Other investigators have documented therapeutic uses of laparoscopy in hemodynamically stable trauma patients.
Repair of diaphragmatic injuries
Laparoscopy has been successfully used for the repair of diaphragmatic injuries. It provides a great exposure and allows suture repair of these injuries. In their series, Mjoli et al.  successfully repaired left-sided diaphragmatic injuries laparoscopically after penetrating thoracoabdominal trauma in 21 out of 22 patients (95.5%). The Eastern Association of Trauma (EAST) Practice Management Guidelines on Selective Non-operative Management of Penetrating Abdominal Trauma supports the use of laparoscopy for evaluation and potential repair of diaphragmatic injuries .
Repair of hollow viscus injuries
Several studies have demonstrated the safety and effectiveness of laparoscopy in the treatment of bowel injuries [133, 134]. Omori et al.  compared laparoscopy vs. laparotomy for management of isolated bowel rupture following blunt abdominal trauma and showed that laparoscopic intervention was associated with less blood loss. Intra-operative and postoperative complications, length of hospital stay, and mortality were similar between the groups. Chol et al.  successfully employed laparoscopy for gastric repair, small bowel repair, resection and anastomosis of small bowel, ligation of bleeding omental and mesenteric blood vessels, and sigmoid colon repair in hemodynamically stable patients after abdominal trauma.
Treatment of complications from non-operative management of solid organ injuries
In appropriately selected hemodynamically stable patients, non-operative management has become a key cornerstone of treatment of intra-abdominal solid organ injuries. This strategy may result in complications such as biliary peritonitis, abscess formation and retained hemoperitoneum . Laparoscopy can be used to evacuate these collections several days after the initial injury, especially when percutaneous drainage has not been successful . Laparoscopy has also been used to evacuate hemoperitoneum after non-operative management of hepatic injuries in a bid to prevent biliary peritonitis . The EAST guideline on non-operative management of blunt hepatic injury recommends laparoscopy as one of the adjuncts for this purpose .