The Association of Propofol Usage With Postoperative Wound Infection Rate in Clean Wounds: A Retrospective Study

OBJECTIVE: To determine if the use of propofol influences the postoperative infection rate of clean surgical wounds in dogs and cats. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: 863 dogs and cats undergoing clean surgical procedures. METHODS: Medical and anesthetic records of surgical cases used as part of a previously described epidemiologic study on postoperative wound infection rates were reviewed. The records of all animals with clean surgical wounds were reviewed to determine if propofol had been used for anesthetic induction or maintenance during the procedure. To determine the effect of propofol use on wound infection rate, data were analyzed using Fisher's exact test, followed by multiple logistic regression to adjust for various factors, including surgery time, time from clipping to surgery, antibiotic usage, coexisting distant infection, endocrine disease, and the use of immunosuppressive drugs in the perioperative period. RESULTS AND CONCLUSIONS: Of 863 dogs and cats with clean surgical wounds, 46 received propofol as part of the anesthetic protocol. A total of 6 of 46 animals (13%) receiving propofol developed postoperative wound infections, compared with 33 of 817 animals (4%) not receiving propofol (P = .014; % difference = 9%; 95% CI = 0.5% to 24%). Adjusting for all other factors evaluated, animals receiving propofol were 3.8 times more likely to develop postoperative wound infections compared to animals not given propofol (95% CI = 1.5-9.9). CLINICAL IMPLICATIONS: Propofol is a lipid-based emulsion capable of supporting microbial growth. Administration of a potentially contaminated solution may contribute to surgical wound infection or other patient morbidity or mortality. Strict aseptic technique in the preparation of the solution and prompt disposal of unused drug are imperative to curtail the potential for extrinsic contamination.     

Comparison of Computed Tomographic and Radiographic Popliteal Lymphangiography in Normal Dogs

Objective: To (1) describe computed tomographic (CT) popliteal lymphangiography; (2) compare the number of thoracic duct (TD) branches detected by CT and by radiography after popliteal lymphangiography; and (3) to compare the number of branches detected after left and right popliteal lymphangiography. Study Design: Experimental study. Animals: Adult dogs (n=6). Methods: A randomly selected popliteal lymph node was percutaneously injected with 12 mL iodinated contrast medium through a 25‐g butterfly catheter over 4–5 minutes. Lateral and ventrodorsal (VD) thoracic radiograph projections and thoracic CT were performed. The procedure was repeated using the contralateral lymph node after a 48–72 hours washout period. Results: One dog had TD branches visible on CT but not on radiographs. A significantly greater number of TD branches were observed with CT popliteal lymphangiography compared with lateral and VD radiographic popliteal lymphangiography (P=.003 and P<.001, respectively). The number of visible TD branches observed between the 6th thoracic and 1st lumbar vertebrae were not significantly different in these dogs (P=.146). A significant difference in number of TD branches observed was not found after left or right popliteal lymph node injection (P=.097). Conclusions: CT popliteal lymphangiography consistently identified a greater number of TD branches when compared with radiographic popliteal lymphangiography. Injection of either popliteal lymph node resulted in the same number of TD branches being observed.     

URETERAL FIBROEPITHELIAL POLYPS IN FOUR DOGS

Four dogs with ureteral fibroepithelial polyps, ranging from 9-12 years of age, are presented in this report. The patients presented with urinary incontinence, urinary tract infection, and/or polydypsia and pollakiuria. All dogs were intact at the time of diagnosis or for the majority of their lives and three were male. Various diagnostic procedures were performed including ultrasonography, contrast radiography, and nuclear scintigraphy. Not all procedures were performed in all patients. Findings included ureteral dilation proximal to the level of an intraluminal mass and ipsilateral hydronephrosis. Unilateral ureteronephrectomy was performed in three dogs with masses in the proximal ureter; ureteral resection and anastamosis was performed in the remaining patient with a mass located in the distal ureter. The same pathologist (RAP) reviewed all four lesions. The lesions appeared polypoid and were attached to the ureteral wall by a thin stalk. Histopathologically, they contained a superficial layer of well-differentiated transitional epithelial cells overlying a prominent fibrovascular stroma with a mild (three dogs) or marked (one dog) degree of lymphoplasmacytic inflammation. This disease may represent a benign neoplasm or a chronic inflammatory reaction and has a good prognosis with surgical removal. Its histopathological characteristics, higher incidence in males, and location more commonly within the upper third of the ureter is remarkably similar to the disease in humans.     

ENDOSCOPIC ULTRASOUND INSTRUMENTATION, APPLICATIONS IN HUMANS, AND POTENTIAL VETERINARY APPLICATIONS

Endoluminal scanning under endoscopic guidance, or endoscopic ultrasonography (EUS), has become the most significant advance for imaging the gastrointestinal (GI) tract wall and contiguous organs in the past 20 years. It was originally designed to overcome the limitations in humans to imaging the abdominal organs transabdominally, such as large penetration depths and GI air. This imaging modality provides detailed images of pathological processes both within and outside of the GI wall since a high-frequency transducer can be brought into close proximity with the target regions. It has found most success in humans for the staging of lung, gastric, and esophageal cancer, the detection of both lymphatic and hepatic metastases, and diagnosis of pancreatitis and pancreatic cancer, as well as achieving an important role in interventional and therapeutic procedures. The EUS examination can be performed to examine both the thorax and abdomen in animals when both conventional transthoracic or transabdominal ultrasound are inadequate due to intervening air, bone, large penetration depths, or obesity. The echoendoscope is similar to a conventional endoscope but has an ultrasound transducer at its tip. Both radial and linear multifrequency scanners are available. Linear scanners allow fine-needle aspiration (FNA) of the bowel wall or extraluminal structures. Transducer coupling is either by direct mucosal contact or by inflation of a water-filled balloon surrounding the transducer. Current thoracic applications for EUS in veterinary medicine include examination of the mediastinum, bronchial lymph nodes, esophagus, and pulmonary lesions as well as FNA of pulmonary masses. Abdominal applications include examination of both pancreatic limbs and the liver, including portosystemic shunts, detection of lymphadenomegaly, and examination of the gastric wall, duodenum, and jejunum. Other potential applications in dogs and cats include tumor staging and intrapelvic ultrasound.     

OSTEOSARCOMA OF THE PATELLA WITH PULMONARY METASTASES IN A DOG

A 6-year-old neutered male Rottweiler was examined for a progressive right pelvic limb lameness. In radiographs of the right stifle, there was an osteolytic lesion with irregular new bone formation along the cranial aspect of the patella consistent with an aggressive bone lesion. In thoracic radiographs, there were multiple soft tissue nodular opacities throughout the lung fields, consistent with pulmonary metastases. Microscopically, fine needle aspirate samples from the right patella contained pleomorphic spindle cells with cytologic features of osteosarcoma. The presence of pulmonary metastases at the time of initial diagnosis in the dog described herein suggests that osteosarcoma of the patella has the potential for similar aggressive biologic behavior as that seen in dogs with appendicular osteosarcoma.     

Quantification of pulmonary to systemic flow ratio by a Doppler echocardiographic method in the normal dog: Repeatability, reproducibility, and reference ranges

Objective

To determine if the pulmonary to systemic flow ratio (Qp/Qs) could be assessed in healthy awake dogs using Doppler echocardiography.

Background

Qp/Qs could provide reliable information in assessing the severity of intracardiac shunts (ICS) by quantifying pulmonary overcirculation. Qp/Qs has been validated against electromagnetic flowmeter methods in experimental canine models. However, its clinical applicability in awake dogs has never been assessed.

Animals, materials and methods

Six healthy dogs were used to determine the repeatability and reproducibility of the technique (Study 1); Qp/Qs was then prospectively assessed in 50 healthy dogs (Study 2). In both studies Qp/Qs was calculated in awake animals using a standardized Doppler echocardiographic method.

Results

Within- and between-day coefficients of variation for Qp/Qs were <10% (Study 1). For Study 2, a relatively wide range of Qp/Qs was found (reference range = 0.71-1.29; mean ± SD = 1.00 ± 0.15).

Conclusions

Qp/Qs can be assessed with good repeatability and reproducibility in healthy dogs. However, the wide range of Qp/Qs obtained in the healthy population may suggest a limited usefulness of this variable for accurately assessing ICS severity in diseased animals. This needs to be assessed in further prospective and longitudinal studies including a large number of animals with ICS of various grades.     

OSTEOCHONDROSIS IN THE LATERAL FEMORAL CONDYLES OF A HORSE

Osteochondrosis of the lateral femoral condyles was diagnosed radiographically in an 8-month-old, female Arabian horse, which had been presented with a hindlimb lameness. The diagnosis was confirmed by gross and microscopic pathology. The location of the lesions was considered unusual for osteochondrosis in the horse.