Impact of a cell salvage device on blood transfusions to dogs undergoing surgery at a referral veterinary hospital

OBJECTIVE

To determine the number of homologous blood transfusions received by canine surgical patients after introducing a cell salvage device (CSD), trends in surgeries requiring blood transfusion, and the incidence of transfusion reactions.

STUDY DESIGN

Retrospective study.

SETTING

Single referral hospital.

ANIMALS

All dogs having surgery at a single center (November 2015 to February 2021).

INTERVENTIONS

Medical records of dogs having surgical treatment, including those that received either an autologous or homologous blood transfusion, were reviewed. The surgical patients were the baseline population, and the 2 transfusion groups were compared within this population to analyze the trends.

MAIN RESULTS

A total of 37 and 86 dogs received autologous and homologous blood transfusions, respectively. There was an upward trend in the number of total monthly blood transfusions. No significant increase in the monthly number of homologous transfusions was observed before or after acquisition of the CSD. There was also an upward trend in total monthly surgeries, including those with higher risks of hemorrhage. Dogs receiving homologous blood transfusions had a higher incidence of clinical signs consistent with transfusion reactions (6.98%).

CONCLUSIONS

An upward trend in autologous blood transfusions was seen with the introduction of a CSD. Hospitals with large surgical caseloads at high risk of hemorrhage may see a decreased need for outsourced blood products with the use of the CSD. The device can lead to a more responsible use of an increasingly scarce resource and decrease the risk of a blood transfusion reaction in dogs.

Urinalysis and culture results of free-catch urine samples in dogs: a randomised controlled trial

OBJECTIVES

To evaluate the prevalence of bacterial presence in free-catch urine samples preceded by either a standardised prepped ("clean-catch") protocol versus unprepped (non-cleaned) voiding.

MATERIALS AND METHODS

The study was a single-centre prospective single-blinded randomised controlled trial. Urine samples were obtained from 100 client-owned dogs presenting for routine evaluation. Dogs were randomly assigned to either the prepped group (preputial or peri-vulvar area cleaned with sterile saline before collection) or the unprepped group (no preliminary cleansing) stratified by sex. Urinalysis and urine culture (blood and MacConkey agar) were performed on all samples. Significant bacterial presence on urine culture was defined as >104 colony forming units (CFU)/mL.

RESULTS

There were no statistically significant associations between prepped versus unprepped collection method or sex with a urinalysis positive for bacteriuria. However, on culture, significant bacterial growth was almost five times more likely to be associated with males relative to females (odds ratio 4.59, 95% confidence interval 1.61 to 13.10). The probability of finding a positive culture was not statistically associated with prep method (odds ratio 1.43, 95% confidence interval 0.50 to 4.08).

CLINICAL SIGNIFICANCE

For the majority of dogs without clinical signs of urinary tract infection, free-catch urine collection does not result in significant bacteriuria found on analysis or culture. The presence of bacteria found in free-catch samples may be secondary to sample contamination or subclinical bacteriuria. Sample contamination or subclinical bacteriuria may be more prevalent in male dogs.

[Urinalysis in dogs and cats, part 1: physical and chemical urinalysis]

The urinalysis of dogs and cats is an important part of the diagnostic evaluation of urinary tract diseases as well as for the identification of systemic diseases. A routine urinalysis consists of a physical and chemical examination of the urine as well as an examination of the urine sediment. Various urine collection methods (free-catch, catheterization, cystocentesis) are available. Each method has multiple advantages and disadvantages. The appropriate method must be chosen individually for each patient depending on the emphasis of the examination. The urine should ideally be examined within 30 minutes of collection as it is prone to change due to time and storage. Physical examination of the urine consists of the determination of urine color, clarity, and specific gravity which provides information regarding the concentration of the urine. The latter is determined by refractometry and needs to be interpreted in the context of the hydration status of the patient. Chemical examination of the urine consists of the determination of the pH value and the presence of blood/hemoglobin/myoglobin, protein, glucose, bilirubin, urobilinogen, nitrite, and ketones. The use of commercially available urine dipsticks is common. These must be stored and used according to the manufacturer's instructions and when interpreting the results, veterinary aspects need to be taken into consideration. The physical and chemical examinations of the urine represent rapid and readily performable methods that provide important information for the diagnosis or the exclusion of numerous diseases.

Multicenter evaluation of decompressive cystocentesis in the treatment of cats with urethral obstruction

OBJECTIVE

To investigate whether decompressive cystocentesis (DC) safely facilitates urethral catheterization (UC) in cats with urethral obstruction (UO).

ANIMALS

88 male cats with UO.

PROCEDURES

Cats were randomly assigned to receive DC prior to UC (ie, DC group cats; n = 44) or UC only (ie, UC group cats; 44). Abdominal effusion was monitored by serial ultrasonographic examination of the urinary bladder before DC and UC or before UC (DC and UC group cats, respectively), immediately after UC, and 4 hours after UC. Total abdominal effusion score at each time point ranged from 0 (no effusion) to 16 (extensive effusion). Ease of UC (score, 0 [easy passage] to 4 [unable to pass]), time to place urinary catheter, and adverse events were recorded.

RESULTS

No significant difference was found in median time to place the urinary catheter in UC group cats (132 seconds), compared with DC group cats (120 seconds). Median score for ease of UC was not significantly different between UC group cats (score, 1; range, 0 to 3) and DC group cats (score, 1; range, 0 to 4). Median change in total abdominal effusion score from before UC and DC to immediately after UC was 0 and nonsignificant in UC group cats (range, -5 to 12) and DC group cats (range, -4 to 8). Median change in effusion score from immediately after UC to 4 hours after UC was not significantly different between UC group cats (score, -1; range, -9 to 5) and DC group cats (score, -1; range, -7 to 5).

CONCLUSIONS AND CLINICAL RELEVANCE

DC did not improve time to place the urinary catheter or ease of UC in cats with UO.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) Transfusion Reaction Small Animal Consensus Statement (TRACS). Part 1: Definitions and clinical signs

OBJECTIVE

To use a systematic, evidence-based consensus process to develop definitions for transfusion reactions in dogs and cats.

DESIGN

Evidence evaluation of the literature was carried out for identified transfusion reaction types in dogs and cats. Reaction definitions were generated based on synthesis of human and veterinary literature. Consensus on the definitions was achieved through Delphi-style surveys. Draft recommendations were made available through industry specialty listservs and comments were incorporated.

RESULTS

Definitions with imputability criteria were developed for 14 types of transfusion reactions.

CONCLUSIONS

The evidence review and consensus process resulted in definitions that can be used to facilitate future veterinary transfusion reaction research.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) Transfusion Reaction Small Animal Consensus Statement (TRACS) Part 2: Prevention and monitoring

OBJECTIVE

To systematically review available evidence to develop guidelines for the prevention of transfusion reactions and monitoring of transfusion administration in dogs and cats.

DESIGN

Evidence evaluation of the literature (identified through Medline searches through Pubmed and Google Scholar searches) was carried out for identified transfusion reaction types in dogs and cats. Evidence was evaluated using PICO (Population, Intervention, Comparison, Outcome) questions generated for each reaction type. Evidence was categorized by level of evidence (LOE) and quality (Good, Fair, or Poor). Guidelines for prevention and monitoring were generated based on the synthesis of the evidence. Consensus on the final recommendations and a proposed transfusion administration monitoring form was achieved through Delphi-style surveys. Draft recommendations and the monitoring form were made available through veterinary specialty listservs and comments were incorporated.

RESULTS

Twenty-nine guidelines and a transfusion administration monitoring form were formulated from the evidence review with a high degree of consensus CONCLUSIONS: This systematic evidence evaluation process yielded recommended prevention and monitoring guidelines and a proposed transfusion administration form. However, significant knowledge gaps were identified, demonstrating the need for additional research in veterinary transfusion medicine.

Feline abdominal ultrasonography: What's normal? What's abnormal? Renal pelvis, ureters and urinary bladder

PRACTICAL RELEVANCE

Abdominal ultrasound plays a vital role in the diagnostic work-up of many cats presenting to general and specialist practitioners. Ultrasound examination of the urinary tract provides important information useful in the investigation of several conditions including ureteral obstruction and cystitis.

CLINICAL CHALLENGES

Despite ultrasonography being a commonly used modality, many practitioners are not comfortable performing an ultrasound examination or interpreting the resulting images. Even for the experienced ultrasonographer, differentiating between incidental findings, such as lipid droplets in the bladder, and pathological changes can be challenging.

AIM

This review, part of an occasional series on feline abdominal ultrasonography, discusses the ultrasonographic examination of the normal and diseased renal pelvis, ureters and urinary bladder. Aimed at general practitioners who wish to improve their knowledge of and confidence in feline abdominal ultrasound, this review is accompanied by high-resolution images and videos available online as supplementary material. Ultrasound examination of the kidneys and perinephric space was discussed in an article published in May 2020.

EQUIPMENT

Ultrasound facilities are readily available to most practitioners, although the use of ultrasonography as a diagnostic tool is highly dependent on operator experience.

EVIDENCE BASE

Information provided in this article is drawn from the published literature and the author's own clinical experience.

Successful management of catastrophic peripheral vascular hemorrhage using massive autotransfusion and damage control surgery in a dog

OBJECTIVE

To describe a case of massive transfusion using unwashed, non-anticoagulated, nonsterile autologous blood in a dog with catastrophic hemorrhage from a peripheral vessel during orthopedic surgery. A damage control surgical strategy was also employed.

CASE SUMMARY

A 6-year-old, 48 kg neutered male Labrador Retriever experienced massive hemorrhage after transection of a large blood vessel while undergoing femoral head and neck osteotomy. Blood was collected from clean, but not sterile, suction canisters and clots were skimmed off. The blood was then transfused back to the dog using a standard in-line blood filter. Approximately 58% of the dog's blood volume was autotransfused in less than 2 hours, thereby meeting the criteria for massive transfusion. Surgery was aborted after hemostasis was achieved by ligation of the vessel and packing of the surgical site. Two units of fresh frozen plasma were administered postoperatively due to the development of a coagulopathy. Hemoglobinuria developed but resolved within 18 hours. Three days later, completion of the surgical procedure was performed without incident. The dog was discharged 4 days after the initial surgery. Marked swelling of the affected limb developed, but resolved after the sixth day. No other significant complications developed.

NEW OR UNIQUE INFORMATION PROVIDED

In this case report, the authors describe the successful management of catastrophic hemorrhage with autotransfusion performed in the absence of sterile collection, cell washing, or anticoagulation. Although not ideal, autotransfusion under these conditions can be lifesaving in situations of massive hemorrhage. This case also highlighted the employment of a damage control surgical strategy.

Association between ultrasonographic appearance of urine and urinalysis in dogs and cats

OBJECTIVE

To evaluate association between ultrasonographic urine echogenicity and sediment examination in dogs and cats.

MATERIALS AND METHODS

Dogs and cats undergoing ultrasound-guided cystocentesis at a multidisciplinary referral hospital. Ultrasonographic images were stored and reviewed by a single, blinded, board-certified radiologist. Urine appearance was described as "echoic" or "anechoic". Urine sediment was examined for bacteriuria, pyuria, haematuria, crystalluria and urine-specific gravity and then classified as "active" or "inactive."

RESULTS

Of the 194 cases included in this study, urine was echoic in 52 and anechoic in 142. Sediment was active in 52 and inactive in 142 samples. Sensitivity and specificity of echoic urine for active sediment were 40% (95% CI: 27 to 55%) and 78% (95% CI: 70 to 85%), respectively. Positive predictive value and negative predictive value of echoic urine for active sediment were 40% (CI 30 to 52%) and 78% (CI 74 to 82%), respectively. If urine-specific gravity was <1.015 urine was always described ultrasonographically as anechoic.

CLINICAL SIGNIFICANCE

Association between sediment analysis and ultrasonographic appearance of urine is poor. Echoic urine had low positive predictive value for active sediment in this study, suggesting that echoic urine alone should not prompt urinary investigations in the absence of other clinical suspicion. Despite a negative predictive value of 78%, urinalysis is still indicated for anechoic urine, especially if urine specific gravity is low.

Urine Cytology: Collection, Film Preparation, and Evaluation

Cytologic examination of the urine sediment in animals suspected of having urinary tract disease or lower urinary tract masses is one of the best means of distinguishing inflammation, infection, and neoplasia and can help determine if a positive dipstick result for hemoglobin/blood is due to hemorrhage or blood contamination. The quality of the specimen collection and handling plays an important role in the quality of results, the validity of interpretations, and selection of appropriate course of action. The method of sample collection aids localization of pathology. Air dry but do not heat fix, freeze, or expose films to formalin fumes, temperature extremes, or condensation.

Autologous blood transfusion in dogs with thoracic or abdominal hemorrhage: 25 cases (2007-2012)

OBJECTIVE

To describe the use and outcome following autologous blood transfusion (ABT) in dogs.

DESIGN

Retrospective study (January 2007-July 2012).

SETTING

Private veterinary referral center.

ANIMALS

Twenty-five dogs that underwent ABT secondary to thoracic or abdominal hemorrhage.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The hospital transaction database was searched using the keyword "autotransfusion" from January 2007 to July 2012. Data collected included signalment, body weight, etiology of hemorrhage, source and method of collection, volumes and method of ABT administration, use of anticoagulant, reported complications, and outcome. Twenty-five dogs were included for a total of 27 ABTs. Causes of hemorrhage included vascular trauma (14/25 dogs, 56%), ruptured tumor (8/25, 32%), and coagulopathy attributed to brodifacoum toxicosis (3/25, 12%). Autologous blood was collected from the abdominal (19/25, 76%), thoracic (5/25, 20%), or abdominal and thoracic cavities (1/25, 4%). Anticoagulant was added to the ABT blood in 13 of 25 (52%) cases. A median ABT volume of 29.3 mL/kg (range 2.9-406.9 mL/kg) was infused through either a 210 μm blood administration filter (21/27, 78%) or an 18 μm hemonate filter (6/27, 22%). Reported complications that may have been associated with ABT included hypocalcemia (4/17, 24%), hemolyzed serum (5/19, 26%), and prolonged coagulation times (4/5, 80%). These complications were considered of minimal clinical significance. Additional blood products were administered in 17 of 25 (68%) dogs. Seventeen (68%) dogs survived to discharge. Cause of death in the remaining cases was euthanasia or cardiac arrest secondary to uncontrollable hemorrhage.

CONCLUSIONS

ABT is an adjunct to volume replacement in dogs with thoracic or abdominal hemorrhage secondary to vascular trauma, ruptured tumor, or anticoagulant rodenticide toxicosis. ABT may be used as bridge to definitive hemorrhage control, particularly when other blood products are not available or affordable. Complications may include hypocalcemia, prolonged coagulation times, and hemolysis.

Probable vasovagal reaction following cystocentesis in two cats

Case summary

This case report describes an acute reaction, thought to be vagally mediated, in two cats immediately following cystocentesis. Both cats were being evaluated for feline idiopathic cystitis and developed bradycardia, hypersalivation, urination and weakness after a blind cystocentesis. Both cats recovered uneventfully with supportive care.

Relevance and novel information

A vagally mediated response may occur in cats after cystocentesis, which is a common procedure performed by veterinary professionals in cats. This response may be very profound and dramatic. Affected cats will likely make an uneventful recovery. This vagally mediated response to cystocentesis, though reported by word of mouth among veterinarians, has not been described in the literature. This is the first documentation of its occurrence in cats.

Outcome of male cats managed for urethral obstruction with decompressive cystocentesis and urinary catheterization: 47 cats (2009-2012)

OBJECTIVE

To characterize the duration of urinary catheterization, length of hospitalization, complications and clinical outcome in cats with urethral obstruction managed with decompressive cystocentesis and subsequent urinary catheterization.

DESIGN

Retrospective, observational, descriptive study.

SETTING

University teaching hospital.

ANIMALS

Forty-seven client-owned male cats diagnosed with urethral obstruction.

MEASUREMENTS AND MAIN RESULTS

The medical records of 47 cats diagnosed with urethral obstruction were reviewed. Treatment of all cats included decompressive cystocentesis, placement of an indwelling urinary catheter and hospitalization for a minimum of 6 hours. Collected data included signalment, body weight, body condition score, owner-reported clinical signs, duration of clinical signs, vital signs, and venous blood gas or chemistry values. Mean duration of urinary catheterization was 27.9 hours, median length of hospitalization was 40 hours, and survival to discharge was 91%. Of 34 cats that had survey abdominal radiographs, 56% (19/34) had loss of peritoneal detail consistent with abdominal effusion. No cat was diagnosed with a ruptured bladder during hospitalization.

CONCLUSIONS

Decompressive cystocentesis, in cats with urethral obstruction, followed by placement of an indwelling urinary catheter, did not result in a diagnosis of bladder rupture in any cat. The source of and clinical significance of the reported abdominal effusion is not known. Survival to discharge, duration of catheterization, and length of hospitalization were similar to previously reported populations.