Endoscopic surgery, including a large variety of thoracoscope and laparoscopic techniques, has become common in human medicine. For example, laparoscopic cholecystectomy has replaced open cholecystectomy as the gold standard for treatment of patients with uncomplicated gallbladder disease.1 In veterinary patients, laparoscopic surgery is becoming increasingly common but is typically restricted to specialty practices and teaching hospitals because of the specialty training and knowledge required to perform the procedures safely and the associated equipment costs. Nonetheless, in part because of client demand, many veterinarians in general practice are currently performing basic laparoscopic procedures in small animals (eg, OVE and prophylactic gastropexy). Several studies2–4 suggest that patients undergoing laparoscopic procedures may experience decreased signs of pain, fewer surgical site infections, and less soft tissue trauma, compared with traditional open surgeries, which is appealing to veterinarians and clients. However, as for endoscopic surgery in general, laparoscopic surgery has a relatively steep learning curve, which may increase surgery time, cost, and the risk of complications when performed by inexperienced practitioners. These factors may dissuade some veterinarians from performing these procedures.
Multiple studies in human surgery have demonstrated that adequate training and experience is critical to the safety of patients undergoing laparoscopic procedures. Laparoscopic surgery presents specific technical challenges, including the fulcrum effect created by the requirement for insertion of instruments through small portals in the body wall, the necessity of viewing the 3-D surgical field on a 2-D screen, and the need for the camera to be under an assistant's control. In particular, the unique surgical situation created by the absence of 3-D visualization can cause a loss of depth perception and alter hand-eye coordination.5 In human surgery, residents initially train via simulation on box trainers and by means of virtual reality, with various requirements to complete skills curricula as they progress to assisting in the operating room.6 In 1 study,7 second-year medical students showed significant improvement with use of a virtual reality trainer for minimally invasive surgical skills; however, their skill plateau was not reached until 21 to 29 repetitions and in some cases > 30 repetitions. For residents in human surgical residency training programs to be eligible for the general surgery board examination, they are required to complete the Fundamentals of Laparoscopic Surgery skills curriculum, which is a comprehensive laparoscopic training program with a certifying test at completion.8 Similar application of simulation-based skills training curricula is being investigated and developed in veterinary surgery.9,10 Fransson et al,9 for example, reported similar results when evaluating skill acquisition by veterinary students, residents, and board-certified surgeons using a low-fidelity laparoscopic trainer.
It has previously been reported that abdominal access is associated with a high rate of complications when performing laparoscopic surgery in human patients. In a study11 of 103,852 procedures, for instance, 82% of vascular injuries and 75% of visceral injuries occurred at the time of the first trocar insertion. In a recent retrospective study12 of 618 dogs undergoing laparoscopic OVE, splenic lacerations reportedly occurred in 6 (1%) patients. The same authors reported postoperative complications in 99 (16%) dogs, including incisional inflammation and infection requiring antimicrobial treatment, incisional seroma formation, and incisional herniation.12 Multiple studies in human patients have reported that the rate of complications in patients undergoing laparoscopic procedures is inversely correlated with surgeon experience.13–15 In a recent study14 evaluating the learning curve for a single surgeon performing urologic laparoscopic surgery, the complication rate plateaued after 601 procedures performed over 3 years.
In addition to technical challenges, the success of incorporating rigid endoscopy and laparoscopy in a general practice is contingent on economic viability.16 In veterinary medicine, there is an absence of economic and clinical data relevant to the implementation of endoscopy and laparoscopy in general practice; however, surgical training laboratories are taught at many professional conferences. Thus, reports on the basic training required for minimally acceptable proficiency, associated equipment and training costs, and acceptable surgery times and complications are needed. As such, the purpose of the study reported here was to evaluate the economic and clinical feasibility of introducing rigid endoscopy and laparoscopy to a single small animal general practice. Specifically, we wanted to compare investment costs with revenue generated during the first 12 months after introduction of rigid endoscopy and laparoscopy to the practice, to identify the training acquired by staff veterinarians and the procedures performed during those first 12 months, to record times for laparoscopic OVE and laparoscopic gastropexy and document any complications associated with these procedures, and to determine client satisfaction with endoscopic and laparoscopic procedures. Our hypotheses were that the introduction of basic rigid endoscopy and laparoscopy in this small animal general practice would be economically and clinically feasible and that client responses would be favorable.
Materials and Methods
Study setting and training
The study setting was a newly opened, privately owned small animal veterinary hospital located in a suburban coastal town in southern California. The hospital had < 350 clients at the outset of the study and was operated by a single veterinarian (BE) for the first 4 months, after which time an associate veterinarian was added for the remainder of the study period. Both veterinarians were general practitioners with internship training and 6 years of experience, but neither had previous endoscopic or laparoscopic experience or training. The laparoscopic equipment was obtained in May 2012, 6 months after the practice opened. The practice owner and primary veterinarian (BE) completed a 2-day, private one-on-one training course conducted in the practice and led by a board-certified surgeon with advanced skills in laparoscopic surgery (JBC). Didactic subject matter included information on patient preparation, anesthetic safety, equipment use and resterilization, and basic procedural instruction. Additionally, the surgeon performed and assisted the trainee with 4 laparoscopic procedures, which included 2 OVEs, 1 OVE and laparoscopic-assisted prophylactic gastropexy, and 1 laparoscopic cryptorchidectomy. The associate veterinarian underwent training via a 2-day continuing education course led by board-certified surgeons proficient in laparoscopya and conducted at a dedicated surgical training facility. The associate veterinarian was then assisted directly by the primary veterinarian while performing her first 5 procedures.
Patient selection
Patients that were examined between May 3, 2012, and May 8, 2013, and underwent laparoscopic OVE, laparoscopic cryptorchidectomy, laparoscopic-assisted gastropexy or visceral biopsy, or other endoscopic procedures (ie, otoscopy, rhinoscopy, vaginoscopy, or preputial exploration) were included in the study. Staff veterinarians recommended laparoscopy versus laparotomy following full discussion with clients on the risks versus potential benefits.
Medical records
Patient history, signalment, date of surgery, procedure performed, surgery time (recorded from the skin incision to completion of skin closure), and complications (if applicable) were recorded. Surgery times for laparoscopic OVE and for procedures performed by the practice owner only were recorded separately. Intraoperative complications were categorized as major or minor. Major complications were defined as complications necessitating conversion to an open procedure, blood transfusion, or reoperation. Minor complications were defined as any complications that did not require conversion or notable intervention such as blood transfusion. Postoperative complications were defined as inflammation, incisional infection, seroma formation, herniation, or documented presence of an ovarian remnant after laparoscopic OVE.
Assessment of client satisfaction
Clients were contacted in person at the time of patient follow-up examination or by telephone and asked whether they were satisfied with their animal's recovery from the procedure. A standardized questionnaire was not used to initiate these conversations.
Equipment
Reusable instrumentation was steam sterilized in the hospital autoclave, and disposable SUDs were ethylene oxide gas sterilized at a local specialty hospital.
Economic analysis
Endoscopic revenue was defined as the gross fees generated from the initial appointment and examination, the procedure (including anesthesia), hospitalization, analgesia, and related medications. Any treatments not necessary for the endoscopic procedure such as flea and heartworm medications, vaccines, and microchips were excluded.
Statistical analysis
Continuous data were evaluated for distribution characteristics with the Shapiro-Wilk test. Parametric continuous data are presented as mean ± SD, and non-parametric continuous data are presented as median and range. The effect of chronological order of surgery on surgery time for patients undergoing laparoscopic OVE was evaluated by means of simple linear regression. Because the practice owner performed laparoscopic OVEs throughout the entire study period and the associate veterinarian performed laparoscopic OVEs only during the last 7 months of the study period, only laparoscopic OVEs performed by the practice owner were included in the linear regression analysis. A value of P < 0.05 was considered significant. All analyses were performed with statistical software.b
Results
Seventy-three animals underwent endoscopic or laparoscopic procedures during the study period, including 71 dogs, 1 cat, and 1 rabbit. For dogs, there were 48 sexually intact females, 12 spayed females, 1 sexually intact male, and 10 castrated males. Median age for all dogs was 10 months (range, 35 to 132.7 months). For dogs undergoing laparoscopic OVE, median age was 7.4 months (range, 35 to 107.7 months). Median body weight for dogs undergoing laparoscopic OVE was 18.7 kg (41.1 lb) and ranged from 1.81 to 54.5 kg (4 to 120 lb). There were 47 breeds represented. The cat was a 5-month-old female domestic shorthair, and the rabbit was a 7-year-old neutered male Holland Lop.
Procedures
During the study period, 78 endoscopic procedures were performed on the 73 animals. All procedures were performed by the 2 practice veterinarians. Laparoscopic OVE (n = 44) and laparoscopic OVE with prophylactic gastropexy (5) were the most commonly performed laparoscopic procedures. Laparoscopic OVE was performed by the practice owner in 34 cases and by the associate veterinarian in 10 cases. Other laparoscopic procedures performed were as follows: ovariohysterectomy (n = 1), cryptorchidectomy (1), gastropexy (1), liver biopsy (1), and intestinal biopsy (1). The most common nonlaparoscopic procedure was video otoscopy (n = 19). Vaginoscopy (n = 2), preputial exploration (2), and rhinoscopy (1) were also performed.
Costs and revenue
The primary equipment,c including telescopes, video camera, light source, recording device, light cable, and video cart, was financed via a 5-year lease at a total cost of $57,50770; $889.60/mo or $10,675.20/y. Sterile camera sleeve covers,c 2 hand pieces for the vessel sealing device,d a CO2 tank and refill, and various other disposable items were purchased separately at a total cost of $994.51 for 12 months. The cost for training was $3,140.00. Therefore, we calculated the total cost for the 12-month study period at $14,80971 (ie, 1 year lease payment, training cost, and disposable items cost).
Total revenue associated with endoscopic and laparoscopic procedures during the 12-month study period was $50,423.63. Mean ± SD total client cost per procedure was $742.60 ± $294.12 for all endoscopic and laparoscopic procedures (n = 78). For the 44 OVE procedures, mean ± SD cost was $708.72 ± $252.84.
Surgery time
Mean ± SD surgery time was 637 ± 197 minutes for all 44 laparoscopic OVE procedures and was 58.6 ± 16.5 minutes for the 34 laparoscopic OVE procedures performed by the practice owner (Figure 1). Mean ± SD surgery time was 73.0 ± 335 minutes for the 5 laparoscopic OVE with prophylactic gastropexy procedures and was 42.2 ± 23.9 minutes for the 19 video-otoscopic procedures.
Scatterplot of surgery time (time from initial skin incision to completion of skin closure) versus surgery date for 34 laparoscopic OVE procedures performed during a 12-month period by a single veterinarian in a small animal general practice in southern California. The solid line represents the linear regression line.
Citation: Journal of the American Veterinary Medical Association 250, 7; 10.2460/javma.250.7.795
Scatterplot of surgery time (time from initial skin incision to completion of skin closure) versus surgery date for 34 laparoscopic OVE procedures performed during a 12-month period by a single veterinarian in a small animal general practice in southern California. The solid line represents the linear regression line.
Citation: Journal of the American Veterinary Medical Association 250, 7; 10.2460/javma.250.7.795
Scatterplot of surgery time (time from initial skin incision to completion of skin closure) versus surgery date for 34 laparoscopic OVE procedures performed during a 12-month period by a single veterinarian in a small animal general practice in southern California. The solid line represents the linear regression line.
Citation: Journal of the American Veterinary Medical Association 250, 7; 10.2460/javma.250.7.795
Complications
For the 54 laparoscopic surgical procedures, there were 12 minor intraoperative complications. Complications included splenic laceration by the Veress needle (n = 3), mild ovarian pedicle hemorrhage (3), breach of asepsis (2), loss of pneumoperitoneum because of excessive port incision length (2), and dropped ovary (2). There were no major intraoperative complications, and no cases required conversion to laparotomy. No postoperative complications were reported.
Client satisfaction
Twenty-four of 73 clients were lost to follow-up; the remaining 49 clients were satisfied with their animal's recovery from the endoscopic or laparoscopic procedure.
Discussion
In the present study evaluating the introduction of basic rigid endoscopy and laparoscopy to a 2-veterinarian small animal general practice in southern California over a 1-year period (2012 to 2013), results suggested that these modalities were clinically and economically feasible. Although considerable initial investment costs and training were required, the surgery times and complications were considered to be acceptable and client satisfaction was high when elective abdominal procedures, including laparoscopic OVE and prophylactic gastropexy, were performed in carefully selected patients.
We suggest that the animals included in the present study were typical of patients examined at a small animal private practice. The median body weight (18.7 kg; range, 1.81 to 54.5 kg) and age (7.4 months; range, 3.5 to 107.7 months) of dogs undergoing laparoscopic OVE were similar to data reported previously for small animal patients undergoing laparoscopic OVE and gastropexy.2,12,17–19 A single domestic shorthair cat underwent laparoscopic OVE, and a single Holland Lop rabbit (Oryctolagus cuniculis) underwent a video-otoscopic procedure during the study period; however, the most commonly performed procedure was laparoscopic OVE in dogs. This was not unexpected in a general small animal practice, because gonadectomy is one of the most common surgical procedures performed.20 Laparoscopic-assisted gastropexy was performed in 6 dogs in this study, a finding that we suggest was also consistent with typical procedures that may be performed in a general small animal practice.21 The most common endoscopic procedure performed was video-otoscopy. In a previous study22 of private practices, otitis externa was the third most common condition in dogs (13% of 31,484 dogs); as such, video otoscopy may be a valuable application of rigid endoscopy in small animal general practice.
A significant negative association between surgery time and experience was documented for patients undergoing laparoscopic OVE in the present study. This was consistent with results of previous reports in which increased laparoscopic surgical experience was associated with decreased surgery time.4,12,23 Although the mean surgery time of approximately 1 hour (mean ± SD, 63.7 ± 19.7 minutes) for laparoscopic OVE in the present study was thought to be reasonable, this was 2 to 3 times as long as the mean surgery time reported for laparoscopic OVE performed by board-certified surgeons.17,19,24 It is likely that the longer times for laparoscopic OVE in the present study were attributable to decreased experience and proficiency when compared with OVE performed by surgical specialists with extensive experience in laparoscopic surgery.
Complications occurred in 12 of the 54 basic laparoscopic procedures in the present study, and all were considered minor. The incidence and types of minor complications were consistent with previous reports,2,17,24,25 and none resulted in adverse outcomes for affected patients. Previously reported complications associated with laparoscopic OVE and laparoscopic-assisted gastropexy include organ laceration and hemorrhage (notably from the spleen and ovarian pedicles), incisional dehiscence, and, less commonly, subcutaneous emphysema.2,3,11,12,23,25–27 Splenic laceration occurred in 3 dogs that underwent OVE in the present study, but no intervention was required in any case, which is also consistent with previous reports.12,18,21 For small animal patients undergoing OVE, open or laparoscopic, the most common complication is hemorrhage from the ovarian pedicle. Previous studies2,12,24–26 have documented minor hemorrhage from the ovarian pedicles in 0% to 43% of patients, which was consistent with findings in the present study (mild hemorrhage in 3 of 54 patients). For patients undergoing laparoscopic-assisted gastropexy, seroma formation and iatrogenic full-thickness perforation of the stomach can occur. The risk for these complications can be minimized with proper surgical technique, including gentle tissue handling, and minimal use of stay sutures because these may increase the risk of full-thickness penetration of the stomach.28 In the present study, no complications occurred in any patients during laparoscopic gastropexy.
The present study also documented the economic feasibility of introducing rigid endoscopy and laparoscopy in this small animal practice, with endoscopy- and laparoscopy-derived revenues during the 12-month study period more than 3 times the direct costs associated with laparoscopic equipment rental and purchase and staff training. The largest cost of introducing endoscopy in this practice was the lease cost of the equipment, which, over the full 5-year lease period, was approximately $54,000. Upkeep of instrumentation was not included in our calculation, but our findings suggested that a positive profit margin resulted from the investment in and use of rigid endoscopy and laparoscopy in this practice.
The economic feasibility of introducing endoscopy and laparoscopy into this small animal practice was reliant on effective marketing, client communication, appropriate pricing, and, most importantly, frequent and regular use of the equipment. Marketing and communication to clients were of paramount importance because endoscopic and laparoscopic procedures are more expensive, compared with traditional alternatives. Thus, the potential benefits of minimally invasive versus traditional open surgery need to be communicated effectively to clients, as was the case for this practice. Communication regarding the procedures was carried out by the practice staff and attending veterinarians, and all staff members were well versed on the potential benefits of endoscopic and laparoscopic procedures. There is some evidence from research in marketing suggesting that individuals may perceive a positive relationship between the quality of a product or procedure and its cost.29 Although endoscopic and laparoscopic procedures are more expensive, pricing should be directed at balancing profitability with affordability so as to ensure regular and frequent use. If equipment is purchased or leased but not used regularly, profit cannot be generated, the veterinarian will not become efficient, and there will be no potential benefit for patients. It has been previously recommended that veterinarians carefully monitor the number of minimally invasive procedures being performed per week and adjust cost as needed to ensure regular use.16 Of course, demographic characteristics play an important role in the feasibility of rigid endoscopy and laparoscopy in small animal practice, and the specific economic circumstances of individual practices will certainly vary.
The need for sterilization and reprocessing of equipment is an important consideration with endoscopic and laparoscopic procedures, with the potential to add considerable expense. These costs are typically factored into the procedure costs and, with the exception of SUDs, are similar to such costs for standard surgical instruments and procedures. Single-use surgical instruments, such as the vessel-sealing device hand pieces purchased in the present study, are usually cost prohibitive in veterinary medicine if not processed for reuse. In this study, the vessel-sealing device SUDs were reprocessed by a nearby specialty hospital free of charge until an ethylene oxide sterilizer was purchased after the conclusion of the study for $6,000. The cost of the ethylene oxide sterilizer unit was not included in the analyses because it was purchased following conclusion of the study but is an acknowledged limitation of the present study. Because SUDs such as the vessel-sealing device hand pieces are important to ensure effective and efficient hemostasis and tissue ligation,30 we suggest that a practice considering investing in and implementing endoscopic and laparoscopic procedures should ensure access to or plan to purchase an ethylene oxide or gas plasma sterilization unit to facilitate device reuse. However, it is also important to note that although reuse of these types of devices is common in some veterinary hospitals, adequate evaluation of the safety and efficacy of reuse has not yet been demonstrated.31–33
Overall client perceptions were positive for patients treated in the present study; however, 24 of 73 clients were unable to be reached for follow-up. Thus, conclusions about client satisfaction for these patients cannot be made. Although no direct comparison with patients undergoing open OVE or gastropexy was performed in the present study, we speculate that less postoperative pain and thus decreased analgesic requirements could have contributed to this outcome.2,26,34
The present study had several limitations. First, the investigation was completed at a single veterinary practice located in a relatively affluent region of southern California; therefore, results do not translate to all veterinary practices and locations. Further, a single veterinarian was responsible for most of the procedures performed. Because of the considerable variability in psychomotor skills among individuals, more extensive training and experience will be required for some individuals.35–37 A single product vendor provided all equipment, and service and instrument quality from other vendors may vary. Furthermore, 24 of 73 clients were lost to follow-up and it is possible that complications, including surgical site infection, client dissatisfaction, or both, were missed. Caution is recommended when considering the implementation of basic endoscopic and laparoscopic procedures in general veterinary practice; adequate initial and ongoing training is essential, and the safety of the patient must be the most important consideration. Clients should be fully informed of the potential risks versus benefits, and complications associated with inexperience, lack of training, or inadequate equipment should not be considered acceptable.
Acknowledgments
This manuscript represents a research project submitted by Dr. Jones to the University of Florida College of Veterinary Medicine as partial fulfillment for the Business Certificate.
Presented in abstract form at the 10th Annual Veterinary Endoscopy Society Scientific Meeting, Key Largo, Fla, May 2013.
ABBREVIATIONS
| OVE | Ovariectomy |
| SUD | Single-use device |
Footnotes
Oquendo Training Center, Las Vegas, Nev.
JMP, version 9.0.2, SAS Institute Inc, Raleigh, NC.
Karl Storz Veterinary Endoscopy-America Inc, Goleta, Calf.
Ligasure Atlas, Covidien Inc, Mansfield, Mass.
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