Exploratory laparotomy is the gold standard for the diagnosis and treatment of dogs with gastrointestinal disease. This procedure is typically performed by means of a large incision, which may extend from the xyphoid to the pubis.1 In humans, open gastrointestinal surgery has been associated with more postoperative pain and greater analgesic requirements ascribed to increased tissue trauma, a higher risk of incisional complications, and prolonged hospitalization due to ileus, compared with laparoscopic and laparoscopic-assisted gastrointestinal surgery.2–6 Laparoscopic-assisted gastrointestinal surgery is effective in managing many conditions in humans,7 although certain contraindications (eg, dense adhesions and pronounced distention) have been determined.8–10
Clinical reports have seldom been published regarding the use of a laparoscopic-assisted approach for treatment of dogs with gastrointestinal disease. In the existing reports,11,12 few complications were described for 14 of 16 dogs and cats discharged the day following surgery. Some evidence exists that laparoscopic gonadectomy and gastropexy and laparoscopic-assist-ed cystotomy in dogs result in less pain and a faster return to typical activity than traditional open-abdomen approaches. Presumably, a laparoscopic-assisted approach to gastrointestinal surgery may also provide similar benefits, compared with a traditional open approach.13–16 However, we are unaware of any reported studies in which a laparoscopy was compared with exploratory laparotomy for the diagnosis of gastrointestinal disease in dogs. Furthermore, a technique for laparoscopic diagnosis of gastrointestinal disease in dogs has not been thoroughly described, and the ability to identify gastrointestinal abnormalities and the rate of conversion from laparoscopy to exploratory laparotomy and open gastrointestinal surgery are also unknown. Consequently, surgeons may be reluctant to recommend laparoscopy to clients despite the potential benefits that may exist.
The purpose of the study reported here was to describe a repeatable technique for laparoscopy in dogs with suspected gastrointestinal obstruction, to compare the diagnoses and procedure durations of laparoscopy and exploratory laparotomy, and to determine when and how frequently conversion from laparoscopy to exploratory laparotomy would be required to obtain a diagnosis and provide treatment. We hypothesized that laparoscopy would be effective for diagnosing the cause of obstruction in dogs with suspected gastrointestinal obstruction and could be performed safely but with a longer procedure duration than gastrointestinal exploratory laparotomy. We also hypothesized that dogs with certain lesions (eg, linear foreign bodies and adhesions) would not be amenable to diagnosis or treatment via a laparoscopic-assisted approach.
Materials and Methods
Animals
Client-owned dogs examined for suspected gastrointestinal obstruction at the Small Animal Hospital of the University of Florida were prospectively enrolled in the study with owner consent between September 15, 2013, and December 15, 2014. Prior to enrollment, a clinical history was collected, and physical examination, CBC, serum biochemical analysis, and abdominal radiography were performed. Dogs with suspected gastrointestinal obstruction without clinically important comorbidities (eg, hypovolemic shock, sepsis, or aspiration pneumonia) were considered eligible. Dogs were excluded when they had a history of previous gastrointestinal surgery, septic peritonitis (diagnosed by peritoneal fluid analysis when applicable), known gastrointestinal adhesions, or evidence of intestinal plication on abdominal radiography.
The study protocol was approved by the University of Florida Institutional Animal Care and Use Committee (protocol No. 201307975). All dog owners were given the option for standard treatment independent of the study and were allowed to withdraw their dogs from the study at any point.
Following enrollment, abdominal ultrasonography and CT were performed for all dogs as a part of a parallel investigation involving comparison of imaging modalities.17 All images were reviewed prior to surgery by a board-certified radiologist and with both of the board-certified surgeons (JBC and MDJ) involved with each patient.
Sedation and anesthesia
Dogs were sedated and anesthetized routinely for exploratory surgery by the attending anesthesiologist, who used a protocol that most often consisted of premedication with an opioid in combination with an α2-adrenoceptor agonist and induction of anesthesia with propofol and maintenance with isoflurane in 100% oxygen.
Laparoscopy
Dogs were prepared for surgery in standard aseptic fashion. Each dog was placed on a rotating traya atop a tilting surgery table to facilitate alteration of patient position during laparoscopy. Patient position was altered as necessary to optimize visibility of all aspects of the gastrointestinal tract and peritoneal cavity. Laparoscopy was performed in all dogs by the same board-certified surgeon (JBC) with a surgical resident assistant.
A 3-cm ventral midline incision was made just caudal to the umbilicus, and a single-incision laparoscopy portb was inserted into the incision as described elsewhere.12,18 Three 5-mm inner cannulas were placed into the port, and the abdomen was insufflated to a pressure of 8 to 10 mm Hg. A 30°, 5-mm laparoscopec was used to visually examine the abdominal viscera. A blunt probe, laparoscopic fan retractor, and laparoscopic grasping forceps were used to manipulate abdominal organs.
With the dog in dorsal recumbency, the blunt probe and fan retractor were used to palpate and elevate liver lobes and to examine their visceral and parietal surfaces. The gallbladder and biliary tree were examined by retraction of the gallbladder ventrally with the aid of the fan retractor or blunt probe. The blunt probe was used to palpate the stomach from fundus to pylorus. The dog was then tilted 45° to the right. The spleen was retracted, and the tip of the left limb of the pancreas and gastric fundus were examined. The descending and transverse colon were elevated with a blunt probe and examined. The dog was then tilted 45° to the left. The pylorus was identified and elevated with a blunt probe to expose the duodenum and the right limb of the pancreas. Both the visceral and parietal surfaces of the duodenum and right pancreatic limb were evaluated and palpated by use of the probe. Laparoscopic still images and video recordings were obtained of gastrointestinal and non-gastrointestinal organs (ie, spleen, adrenal glands, kidneys, and urinary bladder).
Following laparoscopic examination, the abdomen was decompressed, and the laparoscopic port was removed. The incision was enlarged by approximately 1 to 2 cm, depending on the size of the dog, and a 3.5-inch Gelpi retractor (initial 13 dogs) or wound retractord (final 3 dogs) was placed in the surgical wound. A loop of jejunum was retrieved from within the abdominal cavity, and the intestine was traced extracorporeally to the ileocecocolic junction and to the caudal duodenal flexure. The abdominal viscera were replaced in the abdominal cavity, and the abdominal retractor was removed. The incision length was measured with a sterile metric ruler.
Each major gastrointestinal region (liver, stomach, duodenum, jejunum, ileocecocolic junction, and colon) was assessed for accessibility (yes or no), gross appearance (normal or abnormal), and apparent condition (eg, distended or erythematous). A final surgical diagnosis (eg, foreign body or adhesions) and whether (yes or no) conversion to an open surgical approach would be required for treatment were recorded.
Exploratory laparotomy
Following laparoscopy, a second board-certified surgeon (MDJ for all but 2 dogs), who was blinded to the laparoscopic findings, performed an exploratory laparotomy in each dog. Briefly, the initial skin incision was extended cranially and caudally as needed, and Balfour retractors were placed. The abdominal viscera were again assessed for accessibility, gross appearance, and apparent condition. The gastrointestinal tract was systematically evaluated. A final surgical diagnosis was determined, and the incision length was measured with a sterile metric ruler. When exploratory laparotomy was finished, the primary surgeon in care of the patient performed definitive treatment of the underlying condition in accordance with the standard of care. Following surgery, dogs recovered in the hospital and were managed in accordance with the standard of care.
Data collection
Various characteristics of the surgical procedures were recorded. Duration of laparoscopy was defined as the interval from the start of the initial skin incision to completion of the extracorporeal evaluation. Duration of exploratory laparotomy was defined as the interval from the start of extension of the abdominal incision to the completion of the procedure. The time required for any surgical treatment was not included. Complications were recorded and defined as major or minor. Major complications included problems such as major hemorrhage requiring transfusion, the need for emergent conversion to an open surgical approach, iatrogenic full-thickness injury to intestine or other hollow viscera, or intraoperative death. Minor complications included problems such as trivial hemorrhage, nonpenetrating injury to a hollow organ, or other visceral injury not requiring any specific treatment.
Statistical analysis
Commercially available statistical softwaree was used for data analysis. Age and body weight of dogs are reported as median (interquartile range). Values of other normally distributed continuous variables (procedure durations and incision lengths) are reported as mean (95% CI). The matched-pairs t test was used to compare data between surgical approaches. Simple linear regression was performed to evaluate the effect of procedure experience on procedure duration. The McNemar test was used to compare the frequency of minor complications between groups. Values of P ≤ 0.05 were considered significant.
Results
Sixteen dogs were enrolled in the study. Median age was 3 years (interquartile range, 1.2 to 6.3 years), and median body weight was 21.1 kg (46.4 lb; interquartile range, 9.9 to 25.3 kg [21.8 to 55.7 lb]). Five dogs were mixed breeds, and the remainder included 1 each of Australian Shepherd, Golden Retriever, Chihuahua, Border Collie, Mastiff, pit bull–type dog, Basset Hound, Doberman, English Bulldog, Springer Spaniel, and Beagle.
All dogs had various signs of gastrointestinal illness at the time of enrolment, the most common of which was acute or chronic vomiting (n = 14). Other initial signs and historic data included anorexia (n = 6), foreign material ingestion (3), diarrhea (3), abdominal pain (1), and weight loss (1). Physical examination findings most commonly included signs of a tense or painful abdomen (n = 13), dehydration (5), tachycardia (3), muscle atrophy (2), and mucoid feces (2). Findings on abdominal radiography, which was performed prior to enrolment for all dogs, were supportive of gastrointestinal disease in all dogs. Findings of ultrasonographic and CT examination for gastrointestinal obstruction were in agreement for all but 1 dog. In this dog, ultrasonography resulted in the incorrect diagnosis of a mechanical obstruction, which was not visible on CT or at surgery.17
Laparoscopy
For 13 of the 16 dogs, the laparoscopic examination was successfully completed. For 3 of 16 dogs, complete laparoscopic examination was not possible. Adhesions prevented access to the aborad portion of the jejunum, ileocecocolic junction, and colon in one dog and to the ileocecocolic region alone in a second dog. Jejunocolic intussusception in a third dog prevented extracorporeal evaluation of the affected intestinal segments.
Accessibility of organs
Laparoscopy provided access to and visibility of the liver, pancreas, stomach, and duodenum in all dogs; the jejunum and ileum in 14 dogs; the cecum in 13 dogs; and the colon in 15 dogs. In comparison, exploratory laparotomy provided access to and visibility of all listed organs in all dogs, except the cecum and colon, which could be accessed in only 15 dogs.
Procedure characteristics
Mean incision length was 4.9 cm (95% CI, 3.9 to 5.9 cm) for laparoscopy and 16.4 cm (95% CI, 14.0 to 18.7 cm) for exploratory laparotomy (P < 0.001). Mean duration of laparoscopy was 36.8 minutes (95% CI, 31.6 to 41.2 minutes), which was significantly (P < 0.001) longer than the mean duration of exploratory laparotomy (12.8 minutes; 95% CI, 11.4 to 14.3 minutes). A significant (P = 0.001) negative association (r2 = 0.53) was identified between duration of laparoscopy and chronological order of patients, indicating that increased surgeon experience resulted in a briefer procedure. No such association was identified for exploratory laparotomy (r2 = 0.02; P = 0.570; Figure 1).
Scatterplots and linear regression lines for procedure duration versus dog number for laparoscopy (A) and subsequent exploratory laparotomy (B) in 16 dogs with suspected obstructive gastrointestinal disease. Dog number coincides with the order in which dogs were evaluated. For laparoscopy, procedure duration was significantly (P = 0.001) and negatively associated (r2 = 0.53) with dog number, suggesting an effect of surgeon experience. For exploratory laparotomy, no such association was identified (r2 = 0.2; P = 0.57).
Citation: Journal of the American Veterinary Medical Association 251, 3; 10.2460/javma.251.3.307
Scatterplots and linear regression lines for procedure duration versus dog number for laparoscopy (A) and subsequent exploratory laparotomy (B) in 16 dogs with suspected obstructive gastrointestinal disease. Dog number coincides with the order in which dogs were evaluated. For laparoscopy, procedure duration was significantly (P = 0.001) and negatively associated (r2 = 0.53) with dog number, suggesting an effect of surgeon experience. For exploratory laparotomy, no such association was identified (r2 = 0.2; P = 0.57).
Citation: Journal of the American Veterinary Medical Association 251, 3; 10.2460/javma.251.3.307
Scatterplots and linear regression lines for procedure duration versus dog number for laparoscopy (A) and subsequent exploratory laparotomy (B) in 16 dogs with suspected obstructive gastrointestinal disease. Dog number coincides with the order in which dogs were evaluated. For laparoscopy, procedure duration was significantly (P = 0.001) and negatively associated (r2 = 0.53) with dog number, suggesting an effect of surgeon experience. For exploratory laparotomy, no such association was identified (r2 = 0.2; P = 0.57).
Citation: Journal of the American Veterinary Medical Association 251, 3; 10.2460/javma.251.3.307
Diagnoses
Primary diagnoses included discrete foreign body (n = 8), linear foreign body (3), adhesions (2), intussusception (1), pseudo-obstructive gastroenteropathy (1), and hepatopathy (1). These primary diagnoses were consistent between laparoscopy and exploratory laparotomy in all 16 dogs. However, given the inability to perform a complete laparoscopic examination in 3 dogs, conversion to exploratory laparotomy would have ultimately been required. Additionally, given the involvement of the stomach, duodenum, or ileocecocolic region in 4 other dogs, incisional extension or conversion to exploratory laparotomy would have been required to surgically treat the identified lesion. Therefore, laparoscopy alone was perceived as inadequate in 7 dogs, yielding a rate of potential conversion to exploratory laparotomy of 7 of 16.
Organ appearance
For 11 dogs, the liver was judged as grossly normal by both the surgeon performing the laparoscopy and the surgeon performing the exploratory laparotomy. In 3 dogs, the liver was judged by both surgeons as abnormal with adhesions, dark parenchymal depressions consistent with infarction, and solitary nodules. In 2 dogs, liver nodules were detected via laparoscopy only; in 1 of these dogs, a diagnosis of metastatic carcinoma was made on histologic evaluation of biopsy specimens.
The stomach appeared grossly normal in 7 dogs and grossly abnormal in 7 other dogs by both diagnostic techniques. Abnormalities included distention (n = 3) and presence of a foreign body (3). In 1 dog with a jejunal foreign body, the stomach appeared mildly distended via laparoscopy but grossly normal by exploratory laparotomy. Additionally, in 1 dog, the stomach appeared grossly normal via laparoscopy but mildly distended by exploratory laparotomy. No apparent gastric foreign body was detected by either exploratory method in that dog. However, during the therapeutic surgical procedure (ie, gastrotomy), a fine linear foreign body was identified, extending from the pylorus to the colon.
The duodenum appeared grossly normal in 6 dogs by both laparoscopy and exploratory laparotomy. In 6 other dogs, both diagnostic procedures revealed a grossly abnormal duodenum. Abnormalities included distention (n = 4), plication (2), adhesions (1), and presence of a linear foreign body (3). In 2 dogs, laparoscopy revealed a mildly distended and hyperemic duodenum, whereas exploratory laparotomy revealed a grossly normal duodenum. A diagnosis of jejunocolic intussusception was made in one of these dogs, and a diagnosis of nonobstructive gastroenteropathy was made in the other. In 2 dogs, laparoscopy revealed a grossly normal duodenum, whereas exploratory laparotomy revealed mild distention (n = 2) and a thickened mesentery (1). A diagnosis of jejunal foreign body was made in the first dog, and a diagnosis of linear foreign body extending from the pylorus to the colon was made in the other dog (the same dog in which both diagnostic procedures failed to reveal the pyloric portion of the linear foreign body).
The jejunum appeared grossly normal in 2 dogs and grossly abnormal in 14 dogs by both diagnostic techniques. Abnormalities included distention (n = 8), erythematous to purple appearance (10), serosal tearing (2), plication (2), adhesions (2), presence of both discrete (6) and linear (2) foreign bodies, and intussusception (1).
The ileocecocolic region appeared grossly normal in 11 dogs and grossly abnormal in 3 dogs by both diagnostic techniques. Abnormalities included distention (n = 3), intussusception (1), and presence of a linear foreign body (1). In 2 dogs, the ileocecocolic junction could not be completely assessed via laparoscopy because exteriorization was not possible without enlargement of the incision. These 2 cases were considered laparoscopic failures, and reasons for the inability to explore the ileocecocolic region were jejunocolic intussusception (n = 1) and mesenteric adhesions (1). Both of these conditions prevented extracorporeal evaluation of the intestine.
The colon appeared grossly normal in 13 dogs and grossly abnormal in the other 3 dogs by both diagnostic techniques. Abnormalities included adhesions (n = 1), thickening (1), and intussusception (1).
Complications
No major complications developed during laparoscopy or exploratory laparotomy. Three of the 16 dogs had minor complications during laparoscopy, and 1 dog had a minor complication during exploratory laparotomy (P = 0.59). The minor laparoscopic complications involved gastrointestinal serosal bruising and tearing as a result of laparoscopic instrument manipulation of the viscera. The minor complication during exploratory laparotomy consisted of mild hemorrhage following manipulation of a mesenteric adhesion.
Discussion
Results of the present study suggested that laparoscopy was a feasible, safe, and clinically applicable minimally invasive approach to diagnosis and evaluation of appropriately selected dogs with suspected gastrointestinal obstruction. Careful patient selection and liberal criteria for conversion to an open surgical approach are recommended if this diagnostic technique is considered. On the basis of our findings, contraindications or reasons for elective conversion include the presence of gastrointestinal adhesions, ileocecocolic intussusception, gastroduodenal involvement, and linear foreign bodies.
The signalment, clinical signs, and physical examination findings reported here are consistent with previously reported data,19–22 suggesting that the included dogs may accurately reflect the canine patient population evaluated in emergency and surgical practices. For most dogs with suspected gastrointestinal obstruction, survey abdominal radiography is performed as the initial diagnostic imaging test.23–25 All 16 dogs in the present study had abdominal radiography performed, and in 3 dogs, nonobstructive gastrointestinal disease was ultimately diagnosed. Abdominal radiography is less accurate than ultrasonography in the diagnosis of obstruction, and the relative diagnostic value of CT in dogs with suspected gastrointestinal obstruction is unknown.23–25
In humans, preoperative CT has been proposed as the gold standard for diagnosis of gastrointestinal obstruction because it can provide accurate information regarding the etiology and anatomic location of an obstruction and reveal potential contraindications (eg, adhesions or gastric involvement) for a laparoscopic surgical approach.26–28 As such, we also evaluated the diagnostic usefulness of abdominal CT for dogs included in the present study, and these findings are reported elsewhere.17
Accessibility of the gastrointestinal tract is perhaps the biggest concern regarding diagnostic laparoscopy in dogs. This concern is not unfounded given that the gastrointestinal tract is complex and vast and extends throughout the entire abdominal cavity. Further, when considering the clinical consequences of a potentially missed lesion, many surgeons may not be willing to consider laparoscopy as an option for their patients. The dilemma is similar for surgeons performing minimally invasive procedures in humans, and it has not been until the past decade that laparoscopic-assisted surgery has become accepted and preferred in many gastrointestinal procedures.7
Laparoscopic gastrointestinal procedures performed in humans include diagnostic exploration, gastrectomy, adhesiolysis, enterectomy, enterotomy, appendectomy, and colectomy, to name a few.7 Initial apprehension regarding such procedures has been overcome for 2 main reasons. First is the development of new technology, such as endoscopic staplers and enteroscopes, which allow surgeons to perform complicated procedures reliably through the small access points characteristic of minimally invasive surgery. Second is the growing experience of surgeons with minimally invasive surgery and, consequently, appropriate patient selection and accurate surgical performance.
In the study reported here, exclusion of dogs that were systemically ill, had peritonitis, or had radiographic evidence of intestinal plication allowed laparoscopic access to all organs of interest in 13 of 16 dogs. We consider this to be a reasonable success rate, and it is consistent with the experience in humans.7,8 Causes attributed to an inability to access some gastrointestinal organs via laparoscopy included intestinal adhesions (n = 2) and a jejunocolic intussusception that precluded exteriorization of the ileocecocolic junction through the assist incision (1). Severe or dense adhesions are a known contraindication to laparoscopic-assisted small intestinal surgery in humans and have been speculated to be so in veterinary studies.7,8,11,12,29 Intestinal adhesions prevent exteriorization of the small intestine and the ileocecocolic junction, which is necessary to perform the procedure as described here. Consequently, known adhesions are a contraindication for laparoscopic examination of the gastrointestinal tract and should be considered an indication for elective conversion until a safe method of adhesiolysis has been demonstrated in dogs.
Lesions involving the ileocecocolic junction, such as the jejunocolic intussusception identified in 1 dog in the present study, are also a contraindication for laparoscopy or an indication for elective conversion in dogs. Lesions involving the ileocecocolic junction are problematic for 2 reasons. First, the affected intestinal segment must be small enough to be exteriorized via the assist incision, and second, the affected intestinal segment must be mobile enough to allow exteriorization from the abdominal cavity. The ileocecocolic junction is tethered dorsally with a short mesenteric ligament, which reduces its ability to be exteriorized relative to the jejunum. Therefore, it is logical that dogs with large affected segments in this region would not be good candidates for laparoscopic examination.
In addition to similar organ accessibility, we found that laparoscopy and exploratory laparotomy were comparable in gross appearance and apparent condition of the primary organs evaluated. With respect to the liver, it was interesting that laparoscopy appeared to offer advantages in 2 dogs in which lesions were not identified by exploratory laparotomy. In one of these dogs, metastatic carcinoma was diagnosed on the basis of histopathologic findings. Although the liver is not a part of the tubular gastrointestinal tract, it was included as a primary organ of interest in our study because some dogs with hepatopathy may have clinical signs similar to those with gastrointestinal obstruction. A small number of dogs were therefore anticipated to have negative results of both diagnostic techniques when the study was designed. Whether laparoscopic liver evaluation offers advantages over gross assessment in the staging of certain neoplastic diseases deserves consideration and investigation.
Findings for the stomach and duodenum were also consistent between diagnostic techniques for 15 of the 16 dogs in the present study. In 1 dog, thickening of the duodenal mesentery was palpable via exploratory laparotomy but not during laparoscopy. In this same dog, a fine linear foreign body was identified extending from the pylorus to the colon. Neither diagnostic technique allowed detection of the pyloric anchor in this dog. Although the linear foreign body was detected by means of palpation of the small intestine via both techniques, thereby enabling diagnosis, we suggest that this case illustrated an important limitation of laparoscopic examination, whereby surgeons are unable to palpate the stomach and descending duodenum with their fingers. Whereas in 2 other dogs, palpation with a blunt probe and laparoscopic examination facilitated correct identification of gastroduodenal foreign bodies, we recommend that the stomach and duodenum be assessed carefully and conversion to an open surgical approach be performed if there is any question about the status of these organs.
One of the authors (JBC) has successfully used intraoperative gastroduodenoscopy in conjunction with laparoscopy in a dog since the study was completed to rule out gastroduodenal involvement, and this approach may be a suitable alternative to an open surgical approach for that purpose. Concurrent intraoperative flexible endoscopic evaluation of the upper gastrointestinal tract is commonly performed in human laparoscopic-assisted gastrointestinal surgery,7 and this approach deserves consideration and future study in veterinary minimally invasive gastrointestinal surgery as well.7 Prudent use of preoperative advanced imaging (eg, ultrasonography or CT) may also assist with assessment of gastric involvement in suspected obstructive gastrointestinal disease.17,23,24
In contrast to the stomach and descending duodenum, the jejunum and ileum are relatively mobile because of the long mesenteric root to which they are attached. This anatomic feature makes them easily accessible during laparoscopy unless abdominal adhesions are present, which was the situation in 2 dogs of the present study. Although the intestinal adhesions were diagnosed intracorporeally via laparoscopy, we were unable to exteriorize and assess the jejunum and ileum completely in both of these dogs. In the 14 remaining dogs, results of gross examination were similar between diagnostic techniques. This was not surprising given that the laparoscopic technique involved extracorporeal examination, similar to exploratory laparotomy. Therefore, dogs with foreign bodies in or diseases affecting the jejunum and ileum that are not adhesive in nature appear to be good candidates for laparoscopy. Seven of the study dogs with discrete foreign bodies between the ascending duodenum and ileum were deemed treatable via laparoscopy. Successful laparoscopic-assisted gastrointestinal surgery has been performed in both dogs and cats with similarly locally confined disease.11,12
The colon was involved in only 3 dogs in the present study: 1 dog with a jejunocolic intussusception, a second dog with mesenteric adhesions, and a third dog with a linear foreign body. Regardless, the colon was readily accessible and assessable by means of the surgical techniques described.
Although some variability existed between surgeons in the terminology used to describe viscera between laparoscopy and exploratory laparotomy, the surgical diagnosis was consistent between techniques. Even in the 3 dogs in which laparoscopic examinations could not be completed, an accurate diagnosis was determined. Therefore, we suggest that the laparoscopic technique described here be considered a viable option for diagnostic exploration of the gastrointestinal tract in appropriately selected dogs with suspected obstructive or nonobstructive gastrointestinal disease.
As with many minimally invasive techniques, laparoscopic examination required significantly more time to perform than did exploratory laparotomy in the present study. We suggest that this is an important consideration when deciding on the appropriateness of laparoscopy for a given patient. Specifically, on the basis of study findings, we suggest that systemically ill and unstable dogs should not be considered suitable candidates for laparoscopic examination (and were excluded from the study for this reason). Prolonged anesthesia in an unstable dog has the potential to result in major anesthetic-related complications, such as aspiration pneumonia, incisional dehiscence, and death.30–34
Interestingly, we found that the time required to perform the laparoscopic examinations decreased over the study period, suggesting an effect of surgeon experience with the technique. As indicated by results of linear regression analysis, approximately half of the improvement in the duration of laparoscopy (r2 = 0.53; P = 0.001) was attributable to this acquired experience, whereas for exploratory laparotomy, no such association was identified. It should be noted that laparoscopic still images and video recordings were obtained during laparoscopy of all dogs, whereas no images were obtained during exploratory laparotomy. The time required to obtain these visual records likely added time to the laparoscopic examinations. However, incision length was more than 3-fold as long with exploratory laparotomy versus laparoscopy in the present study. So considering together the experience effect of laparotomy, time required for laparoscopic image acquisition, and time required to close the laparoscopy and laparotomy incisions, some of the additional time needed to complete a laparoscopic examination should be offset.
Because laparoscopy was immediately followed by exploratory laparotomy in the dogs of the present study, differences between diagnostic techniques in the degree of postoperative pain or the risk of surgical site complications could not be evaluated. However, in 2 studies11,12 of dogs and cats undergoing laparoscopic-assisted gastrointestinal surgery, all cats (7/7) and 5 of 7 of dogs were discharged from the hospital the day following surgery, and all had good clinical outcomes. Some evidence also exists to suggest that minimally invasive surgery in dogs may be associated with a lower rate of surgical site infection than an open surgical approach.15 To definitively determine whether laparoscopic-assisted gastrointestinal surgery causes less pain, decreases the risk of surgical site infection, or both, relative to an open surgical approach, a prospective controlled study is required.
Important limitations of the present study included a small sample size and potential bias introduced by the requirement that dogs needed to have had preoperative imaging performed to be included in the study. The prospective controlled nature of this study precluded attainment of a large sample size, and preoperative imaging is recommended prior to surgical intervention in dogs with suspected gastrointestinal disease. As such, we believe that our approach and results should be reflective of a typical clinical situation.
In the study reported here, laparoscopy was found to be a feasible, clinically applicable, and minimally invasive method for diagnostic exploration of the gastrointestinal system in selected dogs with suspected gastrointestinal obstruction. Liberal criteria for conversion to an open surgical approach are recommended when laparoscopy is considered for the diagnosis of gastrointestinal lesions in dogs. Contraindications include presence of intestinal adhesions, linear foreign body, ileocecocolic lesions, and disease affecting the gastroduodenal region. Additional research is needed to determine whether gastroduodenoscopy is indicated to improve assessment of the upper gastrointestinal tract and to determine whether significant benefits exist of laparoscopy versus exploratory laparotomy for dogs with gastrointestinal disease.
Acknowledgments
Supported by a seed grant from the American Kennel Club Canine Health Foundation.
ABBREVIATIONS
| CI | Confidence interval |
Footnotes
TT endoscopic positioner, Apexx Veterinary Equipment Inc, Englewood, Colo.
SILS port, Covidien, Mansfield, Mass.
HOPKINS II, Karl Storz GMBH & Co KG, Tuttlingen, Germany.
Alexis, Applied Medical Inc, Rancho Santa Margarita, Calif.
JMP, version 9.0.2, SAS Institute Inc, Raleigh, NC.
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