Risk factors, prognostic indicators, and outcome of pyothorax in cats: 80 cases (1986-1999)

Successful Management of Recurrent Pyothorax in a Cat: Clinical Findings with Medical and Surgical Approaches

Feline pyothorax or thoracic empyema is a condition characterized by the accumulation of purulent exudate within the thoracic cavity due to infection [...].

Emergency Dyspnea in 258 Cats: Insights from the French RAPID CAT Study

Dyspnea is common in feline emergency medicine. Dyspneic cats are often unable to tolerate additional diagnostic tests upon admission. The aim of this study was to determine the relative frequency of the causes of severe dyspnea in cats and to identify clinical indicators that could guide immediate management. Records of 312 severely dyspneic cats admitted over a 5-year period to our institution's emergency and critical care unit were retrospectively reviewed. The cause of dyspnea was identified for 258 cats, representing 83% of the cases. This study focused solely on these 258 cats. Respiratory causes accounted for 33% of cases, followed by cardiac causes (25%) and both traumatic and neoplastic causes (21% each). Pleural effusion was present in 39% of the cats, with various origins: cardiac (38%), respiratory (pyothorax, feline infectious peritonitis, 30%), neoplastic (23%), and traumatic (9%). Male cats were significantly overrepresented in the cardiac and respiratory groups. The median age differed according to the cause (2 years for traumatic causes, 6 years for respiratory causes, and approximately 11 years for cardiac and neoplastic causes). Cats with cardiac disease were significantly more often hypothermic. Hyperthermia was not systematically indicative of an infectious process. No clinical element (temperature, heart rate, cardiac auscultation, etc.) allowed for predicting the cause of dyspnea. In-hospital mortality was 44%, varying according to the cause (78% for neoplastic causes, 40% for traumatic causes, 37% for cardiac causes, and 30% for respiratory causes). In conclusion, the four main categories of causes were represented in approximately equal proportions, which contrasts with the results of the British RAPID CAT study, where cardiac causes accounted for nearly two-thirds of dyspnea cases. In the dyspneic cats in this series, the clinical presentation did not allow clinicians to identify a particular cause. This highlights the importance of non-invasive examinations such as POCUS (point-of-care ultrasound), which has become a routine test in emergency medicine. However, this importance should not lead to underestimating the continued value of radiography when the cat's clinical condition allows for image acquisition.

Recommended recumbency to avoid insertional complications during small-bore wire-guided thoracostomy tube placement in cats-a cadaver study

BACKGROUND

Small-bore wire-guided thoracostomy tubes (SBWGTT) are commonly used in cats to manage pleural disease and generally have a low complication rate. Our study aimed to explore the correlation between recumbency of cats, placement method, and the occurrence of insertional complications to identify risk factors during SBWGTT placement. In this experimental cadaveric study, SBWGTT placement using a modified Seldinger technique was conducted in 24 feline cadavers. Cats, euthanized for reasons unrelated to the study, were randomly assigned to pleural effusion (EFF; n = 12) and pneumothorax (PNEU; n = 12) groups. Each cadaver was intubated and ventilated with a peak inspiratory pressure (PIP) of 10 mmHg, and sterile saline or air was instilled into the thorax over a 5 mm thoracoscopic trocar in the fourth intercostal space (ICS). Instillation was stopped when the lateral thoracic wall to lung distance (TWLD) reached 10 to 12 mm, measured with ultrasound in the favorable position. Sternal recumbency was the favorable position for the EFF group, and lateral recumbency for the PNEU group. Following the placement of the first SBWGTT in each group, the cadavers were positioned unfavorably (lateral recumbency for EFF group, sternal recumbency for PNEU group), and a second drain was introduced contralaterally. A bilateral 8th ICS thoracotomy was then performed to visually assess intrathoracic structures and drain integrity. A binary logistic regression mixed model was conducted to determine interaction between the induced condition and body position.

RESULTS

A total of 48 SBWGTTs were placed, with complications observed in 33.3% (8/24) of cases. Five of these were major complications consisting of lung lacerations. Complications were more common in the unfavorable position, accounting for 75% of cases, although this result was not statistically significant. The odds of complication rates were > 70% in the unfavorable position and decreased with an increase in TWLD (< 30%).

CONCLUSION

Complications associated with SBWGTT placement are influenced by recumbency, although the data did not reach statistical significance. Placing cats in lateral recumbency for pneumothorax treatment and sternal recumbency for pleural effusion treatment may reduce insertional complications.

2022 Update of the Consensus on the Rational Use of Antithrombotics and Thrombolytics in Veterinary Critical Care (CURATIVE) Domain 1- Defining populations at risk

OBJECTIVES

To expand the number of conditions and interventions explored for their associations with thrombosis in the veterinary literature and to provide the basis for prescribing recommendations.

DESIGN

A population exposure comparison outcome format was used to represent patient, exposure, comparison, and outcome. Population Exposure Comparison Outcome questions were distributed to worksheet authors who performed comprehensive searches, summarized the evidence, and created guideline recommendations that were reviewed by domain chairs. The revised guidelines then underwent the Delphi survey process to reach consensus on the final guidelines. Diseases evaluated in this iteration included heartworm disease (dogs and cats), immune-mediated hemolytic anemia (cats), protein-losing nephropathy (cats), protein-losing enteropathy (dogs and cats), sepsis (cats), hyperadrenocorticism (cats), liver disease (dogs), congenital portosystemic shunts (dogs and cats) and the following interventions: IV catheters (dogs and cats), arterial catheters (dogs and cats), vascular access ports (dogs and cats), extracorporeal circuits (dogs and cats) and transvenous pacemakers (dogs and cats).

RESULTS

Of the diseases evaluated in this iteration, a high risk for thrombosis was defined as heartworm disease or protein-losing enteropathy. Low risk for thrombosis was defined as dogs with liver disease, cats with immune-mediated hemolytic anemia, protein-losing nephropathy, sepsis, or hyperadrenocorticism.

CONCLUSIONS

Associations with thrombosis are outlined for various conditions and interventions and provide the basis for management recommendations. Numerous knowledge gaps were identified that represent opportunities for future studies.

Retrospective Evaluation of the Use and Complications of Small-Bore Wire-Guided Thoracostomy Tubes in Dogs and Cats: 156 Cases (2007–2019)

Background

Small-bore wire-guided thoracostomy tubes (SBWGTT) are commonly used in small animals for management of pleural space disease. We aimed to evaluate the indications, placement locations, types of complications, and complication rate of small-bore wire-guided thoracostomy tube placements in dogs and cats in a university setting.

Methods

Electronic medical records of patients that underwent SBWGTT placement were reviewed. Signalment, disease, outcome, indication for thoracostomy tube, placement location, number of attempts, diagnostic imaging, number, and type (insertional, technical, and infectious) of complications were recorded. Logistic regression analysis was performed to determine risk factors for complications.

Results

A hundred fifty-six cases were identified between 2007 and 2019. Traumatic pneumothorax (33%), pyothorax (25%), and spontaneous pneumothorax (16%) were the most common indications for placement of a SBWGTT. Complications developed in 50 cases (32%). Technical and insertional complications accounted for 21.7% and 14.1% of all cases. Infectious complications were rare with 3.1% of all cases. Pneumothorax (19%), soft tissue swelling at insertion site (14%), and kinking of the chest tube (13%) were most common. Accidental lung perforation was reported in 5/50 complications (7%). Multiple chest tube placement attempts were associated with complications (OR = 6.01 CI: 2.13 to 16.93 p = 0.0007).

Conclusions

Complications of SBWGTT placement occurred in one third of cases. Serious complications such as accidental lung perforation was reported in two cases. Complications were associated with number of attempts.

Retrospective analysis of radiographic signs in feline pleural effusions to predict disease aetiology

Background

The objectives of the study were to determine the prevalence of underlying conditions causing pleural effusion in cats and to calculate the positive predictive values, negative predictive values, sensitivity and specificity of radiographic signs to predict aetiology of the pleural fluid.

Methods

Data from 148 cats with pleural effusion and diagnosed with known aetiologies were retrospectively analysed. Sixty one cats had thoracic radiographs evaluated by consensus through pre-defined radiographic signs by two radiologists blinded to the diagnoses.

Results

Congestive heart failure (53.4%) was the most common diagnosis, followed by neoplasia (20.3%), pyothorax (10.8%), idiopathic chylous effusion (5.4%), feline infectious peritonitis (1.4%) and "other" or cats with multiple diagnoses (total 8.8%). Cats with an enlarged cardiac silhouette had a high positive predictive value of congestive heart failure (90%). Mediastinal masses (100%)and pulmonary masses (100%) were highly predictive of neoplastic disease. Pulmonary nodules (50%) were poorly predictive of neoplastic disease. The remainder of the radiographic variables were not informative predictors of underlying disease.

Conclusions

In our sample of cats, congestive heart failure was the most common cause of pleural effusion. Radiographically enlarged cardiac silhouette and presence of a mediastinal mass may be useful predictors of aetiology, however there are limitations to the use of radiography alone as a diagnostic tool.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03218-3.

Therapy of Pyothorax in Cats via Small-Bore Thoracostomy Tube in Terms of Efficacy, Complications and Outcomes

Simple Summary

With this study we present our therapeutic strategy for cats with purulent fluid accumulation in the thorax. In addition to the systemic administration of antibiotics, the aim of the therapy is always the drainage of the purulent fluid from the thorax. For this purpose, we use a particular small-bore chest drain. The first aim of our study is to assess the efficacy and complication rate of our drainage. The second objective is to evaluate two treatment groups regarding their disease outcomes. We were able to show that our small-bore chest drain is similarly effective to the traditionally used large-bore drains. At the same time, we had a very low drain-associated complication rate. We detected no difference between the treatment groups and, thus, no effect on survival by early placement of bilateral drains into the thoracic cavity or lavage of the thoracic cavity with a heparinised solution. Our study supports the theory that drainage of purulent fluid from the thoracic cavity in cats can be performed with small-bore drains with good results and minimal risk of complications.

Abstract

First-line therapy for cats with pyothorax consists of intravenous antibiotics, drainage of the septic pleural effusion and closed-chest lavage. Large-bore thoracostomy tubes are traditionally used for drainage, but case series indicate a comparable efficacy using small-bore tubes. In this retrospective study, we describe a new technique of sheath-guided small-bore (6 F) thoracostomy tubes in cats with pyothorax and evaluate their efficacy and complications. Additionally, we compare outcomes between two treatment groups. Placement and use of the small-bore thoracostomy tubes described here has a low complication rate of 4% (3/67 tubes), and 53% (24/45) of the cats could be treated with thoracostomy tubes and closed-chest lavage according to the protocol. The success rate is reduced by 18% (8/45) due to deaths caused mainly by sepsis, 16% (7/45) due to structural diseases requiring surgery and a further 14% (6/43) due to lavage failures that could only be cured after additive therapy (thoracotomy or fibrinolysis). The long-term prognosis was very good, with a survival rate one year after discharge of 94% (30/32). We detected no effect on survival by early placement of bilateral thoracostomy tubes or closed-chest lavage with a heparinised solution. In conclusion, therapy of pyothorax with small-bore thoracostomy tubes is as successful as therapy with large- or medium-bore tubes.

A Retrospective Study on Bacteriology, Clinicopathologic and Radiographic Features in 28 Cats Diagnosed with Pyothorax

This retrospective study aimed to determine the etiological, clinicopathological, and radiographic features and outcome of feline pyothorax cases. Medical records from twenty-eight cats with pyothorax aged from 4 months to 10 years (median 10 months) diagnosed between 2013 and 2020 were reviewed. Dyspnoea (75.0%), abnormal lung sounds (75.0%) and open-mouth breathing (64.3%) were the predominant respiratory signs. Leucocytosis (61.5%), particularly monocytosis (68.0%), and hyperglobulinaemia (65.4%) were among the most prominent findings in blood analysis. Bilateral pleural effusion was found in 67.9% of the thoracic radiographs. A total of 47.4% of the cytological samples revealed the presence of bacteria, while all had positive bacterial growth. Pasteurella multocida, E. coli, Streptococcus spp., and Staphylococcus spp. were the predominant aerobic bacteria isolated from pleural effusion samples. A chest tube was placed in 64.3% of the cats and 66.7% of cats with chest tubes survived. In total, 46.4% of cats with pyothorax recovered. Amoxicillin-clavulanate was the antimicrobial of choice against aerobic bacteria found in this study and should be given in combination with antimicrobials that cover anaerobic bacteria. Chest tube placement is crucial for treatment success. Cytological results and bacterial culture may not be consistent; thus, bacterial culture should be performed for every case.

Influence of living in a multicat household on health and behaviour in a cohort of cats from the United Kingdom

BACKGROUND

Living in a multicat household has been implicated as a risk factor for various feline issues, but evidence is often anecdotal or based on retrospective studies.

METHODS

Data from the Bristol Cats Study, a UK longitudinal study of pet cats, were used. Cats were included if they had remained in either a single cat or multicat household between questionnaires 1 (two months old to four months old) and 5 (two-and-a-half years old). Univariable and multivariable logistic regression models were used to analyse associations between single cat/multicat households and measures of health and behaviour (overweight/obesity, abscesses/cat bites, negative interactions with owner and periuria). Multicat households were also subcategorised according to whether owners had reported agonistic behaviour between household cats.

RESULTS

There was no evidence of association between household type and the likelihood of obesity, abscesses or periuria. The likelihood of negative interactions with the owner (eg, growling or hissing) was influenced by the cats' relationships; cats in non-agonistic multicat households had decreased odds of negative interactions with the owner, compared with single and agonistic multicat households (P<0.001).

CONCLUSION

Living in a multicat households per se was not a risk factor for the health and behaviour issues investigated, but the intercat relationship is important.

Short- and long-term outcome in cats diagnosed with pyothorax: 47 cases (2009-2018)

OBJECTIVES

The aims of this retrospective study were to report the short- and long-term outcome in cats treated for pyothorax and to identify prognostic indicators as well as determine recurrence rate.

METHODS

Medical records from April 2009 to August 2018 were retrospectively reviewed. Cases were included if a diagnosis of pyothorax was confirmed via cytology and/or culture of pleural fluid. Cats diagnosed with or suspected of having other thoracic diseases and cats with no evidence of pleural effusion were excluded from the study.

RESULTS

Fifty-five cats met the inclusion criteria. Eighty five percent (n=47) cats underwent medical management with thoracostomy tubes, pleural lavage and broad-spectrum antibiotics. Fifteen percent (n=5) cases failed medical treatment and underwent thoracotomy. Twenty eight percent (n=13) did not survive to hospital discharge. Short-term survival (14 days) was achieved in 72% (n=34). Long-term follow-up was available for 31 of 34 with a long-term survival rate of 68% (n=30). The recurrence rate was 6% (n=2).

CONCLUSION

For cats with pyothorax that survive to discharge the prognosis is excellent and the condition is associated with a low recurrence rate.

The use of small-bore wire-guided chest drains for the management of feline pyothorax: A retrospective case series

Background:

Pyothorax in cats is routinely managed, at least initially, with thoracic tube placement associated with systemic antimicrobial administration. Traditionally, large-bore trocar-type thoracostomy tubes have preferentially been used for the drainage of thick material from the pleural space. In recent years, the use of small-bore wire-guided thoracic drains has increased in both small animals and in humans. Few studies have highlighted the efficacy of small-bore wire-guided thoracostomy tubes.

Aim:

The purpose of this study was to describe the use of small-bore wire-guided thoracostomy tubes in feline pyothorax in terms of efficacy, safety, and outcome.

Methods:

Cats with pyothorax managed with small-bore thoracostomy tubes (SBTTs) (2015–2018) were retrospectively studied. The number of drains inserted, the need for anesthesia and analgesia for chest tube placement and maintenance, and related major and minor complications were reviewed. Clinical data, diagnostic results, treatment, and outcome were recorded.

Results:

Ten cats were enrolled. Thoracostomy tube placement was unilateral in 7/10 cats, despite the presence of bilateral effusion in 9/10 cats, and required sedation (8/10) or anesthesia (2/10). Three cats experienced minor complications during the chest tube insertion, including self-limiting pneumothorax (1/3) and malpositioning (2/3). One cat had a major complication (non-functional malposition) requiring reposition of the drain. Pain management was adequately achieved using opioids (8/10) or opioids plus nonsteroidal anti-inflammatory drugs (2/10). Partial chest tube occlusion occurred in three cases and it was resolved with lavage. In one case, the occlusion was complete, requiring drain removal. Three out of 10 cats were treated medically, combining thoracostomy tubes and antibiotics, while 7/10 cats underwent surgery. All the cats survived.

Conclusion:

SBTTs represent a safe and effective option for the initial management of feline pyothorax. In fact, mainly minor complications were reported during insertion and usage. The SBTTs were well tolerated by the cats with a satisfactory performance in terms of exudate drainage in most cases. The combined use of a small-bore thoracostomy drain together with the common practice of surgical treatment might have resulted in the successful management of the cases presented.

Canine and Feline Exudative Pleural Diseases

Exudative pleural diseases are a common cause of respiratory distress and systemic illness in dogs and cats. This article covers the pathophysiology, development, and classification of exudative pleural effusions. The most current diagnostic strategies, causes, imaging findings, and medical or surgical treatment options for select diseases are reviewed in detail.

Spontaneous cholecystopleural fistula leading to biliothorax and sepsis in a cat

Case summary

A 13-year-old spayed female domestic shorthair cat presented with pleural effusion and suspected triaditis. Intake vitals and leukocytosis were consistent with a diagnosis of systemic inflammatory response syndrome. Biochemical analysis confirmed a pleural fluid-to-serum bile ratio consistent with a diagnosis of biliothorax. Abdominal ultrasound failed to identify a definitive gall bladder but noted a hypoechoic tubular structure ventral to the liver and contacting the diaphragm. Thoracic ultrasound identified a hyperechoic structure contacting the diaphragm at the same location. Thoracoabdominal CT scan identified a fluid-dense tubular structure extending from ventral to the liver, through a diaphragmatic defect and directly communicating with the pleural space, suspected to be an abnormal gall bladder. The cat was humanely euthanized, and post-mortem analysis confirmed a cholecystopleural fistula arising from the gall bladder with multifocal abscesses, mixed inflammatory hepatic infiltrates and small-cell gastrointestinal lymphoma. Culture of the abscess isolated Parabacteroides merdae, meeting the reported feline criteria for sepsis.

Relevance and novel information

To our knowledge, spontaneous cholecystopleural fistula formation leading to biliothorax and sepsis has not been previously reported in the cat. This case highlights a novel sequela of gall bladder disease in this species, and biliothorax should be a differential diagnosis for pleural effusion in cats with evidence of cholecystitis or triaditis.

Pericardial flap to repair a pulmonary laceration in a cat with pyothorax

Case summary

A 2-year-old female neutered domestic shorthair cat was presented for investigation of acute onset tachypnoea and dyspnoea. Pyothorax was diagnosed based on thoracic radiographs and fluid analysis. Medical treatment consisted of bilateral thoracostomy tube placement, antibiotic therapy and thoracic lavage. After 12 days of medical management infection was still present, warranting exploratory thoracotomy. At surgery, encapsulated abscesses were found in the left lung, right cranial and right middle lobes. The right caudal lobe was the only macroscopically non-abscessated lobe, and appeared to have a parenchymal laceration 8 mm long over the dorsolateral surface. Following partial pericardiectomy, mediastinectomy and debridement of abscesses, a pericardial flap was reflected caudolaterally and apposed over the laceration to seal the affected lung lobe. This flap was sutured to a rim of fibrinous adhesion that was partially covering this lobe. After 8 days the cat was discharged with antibiotic therapy for 3 more weeks. Follow-up assessment at 19 and 38 weeks postoperatively confirmed the cat to have good exercise tolerance. Thoracic radiographs at 19 weeks revealed good bilateral aeration of the pulmonary parenchyma without pleural effusion.

Relevance and novel information

Lung lobe laceration can be treated by lung lobectomy or direct suturing of the lung parenchyma. This is the first report using a pericardial flap to repair a lung laceration. Pericardial flap was successfully used to treat this lung laceration where lobectomy was contraindicated. Encouraging results were present at 8 months postoperatively.

Fluoroscopically guided wide-bore thoracostomy tube placement: Description of the technique and comparison to blind placement

OBJECTIVE

To describe and compare fluoroscopic guidance for placement of wide-bore thoracostomy tubes (FGTT) to traditional, blind placement of thoracostomy tubes (BPTT).

STUDY DESIGN

Prospective clinical trial.

ANIMALS

Twenty client-owned dogs.

METHODS

Dogs requiring medical management of pleural effusion received a BPTT, whereas dogs undergoing postoperative management of pneumothorax and/or pleural fluid after lateral thoracotomy received an FGTT. Time of placement, accuracy of positioning, radiation exposure, and complications were compared between groups.

RESULTS

Initial placement of BPTT took a mean of 168 seconds (range, 89-197), whereas adequate placement was radiographically confirmed at 20 minutes and 38 seconds (range, 7 minutes and 57 seconds to 39 min). Initial placement of FGTT took a mean time of 108 seconds (range, 50-341, P = .17), and adequate placement was confirmed at 125 seconds (range, 50-341, P < .001). Major errors in placement requiring removal and replacement occurred in 2 dogs for BPTT and in none for FGTT. Procedural complications did not differ between groups, and no postoperative complication occurred within the first 12 hours after placement. Radiation entrance surface dose was lower in the BPTT group (P = .004), but stochastic radiation doses did not differ.

CONCLUSION

Fluoroscopic guidance of wide-bore thoracostomy tubes accelerated the time to accurate tube placement and alleviated the requirement for removal and replacement in this population. Although use of fluoroscopy increased radiation entrance surface dose, the dose was not clinically significant.

CLINICAL SIGNIFICANCE

Fluoroscopic guidance of wide-bore thoracostomy tubes should be considered as an alternative to traditional, blind placement.

Clinical, laboratory, and hemostatic findings in cats with naturally occurring sepsis

OBJECTIVE To characterize clinical and laboratory findings in cats with naturally occurring sepsis, emphasizing hemostasis-related findings, and evaluate these variables for associations with patient outcomes. DESIGN Prospective, observational, clinical study. ANIMALS 31 cats with sepsis and 33 healthy control cats. PROCEDURES Data collected included history; clinical signs; results of hematologic, serum biochemical, and hemostatic tests; diagnosis; and outcome (survival vs death during hospitalization or ≤ 30 days after hospital discharge). Differences between cats with and without sepsis and associations between variables of interest and death were analyzed statistically. RESULTS The sepsis group included cats with pyothorax (n = 10), septic peritonitis (7), panleukopenia virus infection (5), bite wounds (5), abscesses and diffuse cellulitis (3), and pyometra (1). Common clinical abnormalities included dehydration (21 cats), lethargy (21), anorexia (18), pale mucous membranes (15), and dullness (15). Numerous clinicopathologic abnormalities were identified in cats with sepsis; novel findings included metarubricytosis, hypertriglyceridemia, and high circulating muscle enzyme activities. Median activated partial thromboplastin time and plasma D-dimer concentrations were significantly higher, and total protein C and antithrombin activities were significantly lower, in the sepsis group than in healthy control cats. Disseminated intravascular coagulopathy was uncommon (4/22 [18%] cats with sepsis). None of the clinicopathologic abnormalities were significantly associated with death on multivariate analysis. CONCLUSIONS AND CLINICAL RELEVANCE Cats with sepsis had multiple hematologic, biochemical, and hemostatic abnormalities on hospital admission, including several findings suggestive of hemostatic derangement. Additional research including larger numbers of cats is needed to further investigate these findings and explore associations with outcome.

Diagnosis and management of pyothorax in a domestic ferret (Mustela putorius furo)

OBJECTIVE

To describe the diagnosis, management, and outcome of pyothorax in a domestic ferret (Mustela putorius furo).

CASE SUMMARY

A domestic ferret was evaluated for a history of lethargy, anorexia, and pyrexia. Pleural effusion was detected with radiography and ultrasonography, and a diagnosis of pyothorax was made following cytologic evaluation of pleural fluid. Bilateral thoracostomy tubes were placed for thoracic drainage and lavage, and the ferret was treated with intravenous crystalloid fluids, antimicrobials, and analgesics. Bacterial culture of the pleural fluid yielded Fusobacterium spp. and Actinomyces hordeovulneris. This treatment protocol resulted in resolution of pyothorax, and a positive clinical outcome.

NEW OR UNIQUE INFORMATION PROVIDED

This is the first reported case of successful management of pyothorax caused by Fusobacterium spp. and A. hordeovulneris in a ferret.

Epidemiology of systemic inflammatory response syndrome and sepsis in cats hospitalized in a veterinary teaching hospital

OBJECTIVE To describe the epidemiology of the systemic inflammatory response syndrome (SIRS) and sepsis in cats hospitalized in a veterinary teaching hospital. DESIGN Observational study. ANIMALS 246 client-owned cats. PROCEDURES During a 3-month period, daily treatment records were evaluated for all hospitalized cats. Information extracted included signalment, temperature, heart rate, respiratory rate, diagnostic test results, diagnosis, duration of hospitalization, and outcome (survival or death). Cats were classified into 1 of 4 disease categories (sepsis [confirmed infection and SIRS], infection [confirmed infection without SIRS], noninfectious SIRS [SIRS without a confirmed infection], and no SIRS [no SIRS or infection]). RESULTS Of the 246 cats, 26 and 3 were hospitalized 2 and 3 times, respectively; thus, 275 hospitalizations were evaluated. When SIRS was defined as the presence of ≥ 2 of 4 SIRS criteria, 17 cats had sepsis, 16 had infections, 81 had noninfectious SIRS, and 161 were classified in the no SIRS category at hospital admission. The prevalence of sepsis at hospital admission was 6.2 cases/100 admissions. Four cats developed sepsis while hospitalized, resulting in a sepsis incidence rate of 1.5 cases/100 hospital admissions. Four of 17 cats with sepsis at hospital admission and 3 of 4 cats that developed sepsis while hospitalized died or were euthanized, resulting in a mortality rate of 33.3% for septic cats; 239 hospitalizations resulted in survival, 28 resulted in euthanasia, and 8 resulted in death. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that many hospitalized cats have evidence of SIRS and some have sepsis. In cats, sepsis is an important clinical entity with a high mortality rate.

Antimicrobial use Guidelines for Treatment of Respiratory Tract Disease in Dogs and Cats: Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases

Respiratory tract disease can be associated with primary or secondary bacterial infections in dogs and cats and is a common reason for use and potential misuse, improper use, and overuse of antimicrobials. There is a lack of comprehensive treatment guidelines such as those that are available for human medicine. Accordingly, the International Society for Companion Animal Infectious Diseases convened a Working Group of clinical microbiologists, pharmacologists, and internists to share experiences, examine scientific data, review clinical trials, and develop these guidelines to assist veterinarians in making antimicrobial treatment choices for use in the management of bacterial respiratory diseases in dogs and cats.

A clinical review of the pathophysiology, diagnosis, and treatment of pyothorax in dogs and cats

OBJECTIVE

To review the current literature in reference to the pathophysiology, diagnosis, and treatment of pyothorax in dogs and cats.

ETIOLOGY

Pyothorax, also known as thoracic empyema, is characterized by the accumulation of septic purulent fluid within the pleural space. While the actual route of pleural infection often remains unknown, the oral cavity and upper respiratory tract appear to be the most common source of microorganisms causing pyothorax in dogs and cats. In human medicine, pyothorax is a common clinical entity associated with bacterial pneumonia and progressive parapneumonic effusion.

DIAGNOSIS

Thoracic imaging can be used to support a diagnosis of pleural effusion, but cytologic examination or bacterial culture of pleural fluid are necessary for a definitive diagnosis of pyothorax.

THERAPY

The approach to treatment for pyothorax varies greatly in both human and veterinary medicine and remains controversial. Treatment of pyothorax has classically been divided into medical or surgical therapy and may include administration of antimicrobials, intermittent or continuous thoracic drainage, thoracic lavage, intrapleural fibrinolytic therapy, video-assisted thoracic surgery, and traditional thoracostomy. Despite all of the available options, the optimal treatment to ensure successful short- and long-term outcome, including the avoidance of recurrence, remains unknown.

PROGNOSIS

The prognosis for canine and feline pyothorax is variable but can be good with appropriate treatment. A review of the current veterinary literature revealed an overall reported survival rate of 83% in dogs and 62% in cats. As the clinical presentation of pyothorax in small animals is often delayed and nonspecific, rapid diagnosis and treatment are required to ensure successful outcome.

Pleural Space Disease

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Abnormalities within the pleural space may include pleural effusion, pneumothorax, or space-occupying soft tissue structures (diaphragmatic hernia, neoplasia).

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A diagnostic thoracocentesis may also prove therapeutic in severely affected patients.

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Fluid analysis and cytologic evaluation should always be performed on aspirates from a patient with newly diagnosed pleural effusion of unconfirmed etiology.

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Aerobic and anaerobic culture and susceptibility testing of suppurative effusions are imperative.

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Comparison of pleural fluid and serum triglyceride levels and cholesterol concentrations are necessary to confirm the diagnosis of chylothorax.

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Clinical evidence of cardiovascular shock often precedes dyspnea in patients with hemothorax.

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Tension pneumothorax, regardless of its origin, rapidly may be fatal. Immediate drainage via thoracocentesis or thoracostomy tube placement is required before taking thoracic radiographs.

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Clinical signs of a traumatic diaphragmatic hernia may be delayed; however, early detection and correction are important because perioperative outcome is worse in chronically affected patients.

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Tools such as ultrasonography, computed tomography (CT), and thoracoscopy are becoming increasingly available to aid in the diagnostic evaluation and treatment of pleural space disease.

Clinical outcome following pneumonectomy for management of chronic pyothorax in four cats

Pneumonectomy is the resection of all lung lobes from one side of the thorax. The clinical findings, treatment and outcome of four cases of feline chronic pyothorax managed with exploratory thoracotomy and pneumonectomy are reported. All cases were initially medically managed with thoracic drain placement and antibiosis. However, resolution was not achieved with medical therapy and diagnostic imaging findings consistent with an area of abscessation or marked lung lobe consolidation were identified, supporting a decision for surgical management. Surgical exploration was performed via median sternotomy and, on the basis of gross inspection, non-functional lung was removed. A left-sided pneumonectomy was performed in three cats and a right-sided pneumonectomy in one. All cases survived to discharge and an excellent quality of life was reported on long-term follow-up. Pneumonectomy appears to be well tolerated in the cat.

Clinical and immunologic assessment of sepsis and the systemic inflammatory response syndrome in cats

OBJECTIVE

To compare clinical findings and inflammatory mediator production among cats with sepsis, cats with noninfectious systemic inflammatory response syndrome (SIRS), and healthy cats.

DESIGN

Case-control study.

ANIMALS

Cats with sepsis (n = 16) or SIRS (19) and 8 healthy control cats.

PROCEDURES

Clinical variables were recorded for each cat, and plasma tumor necrosis factor (TNF) and interleukin (IL)-1β activities and IL-6 and CXC chemokine ligand (CXCL)-8 concentrations were determined at initial evaluation.

RESULTS

Clinicopathologic abnormalities associated with sepsis in cats included a high band neutrophil percentage, eosinopenia, hyponatremia, hypochloremia, hypoalbuminemia, hypocalcemia, and hyperbilirubinemia. When the sepsis and SIRS groups were compared, the only significant differences in the CBC and plasma biochemical findings were band neutrophil percentage and albumin concentration. Cats with sepsis had significantly greater plasma TNF activity than did healthy cats and were more likely to have detectable concentrations of IL-6 than were cats with SIRS or healthy cats. Plasma IL-1β activity did not differ among groups, and CXCL-8 was not detectable in most (32/43) cats. Mortality rate was not significantly greater for cats with sepsis (7/16) than for cats with SIRS (5/19). Plasma IL-1β activity and IL-6 and chloride concentrations were the only variables correlated with nonsurvival in the sepsis group.

CONCLUSIONS AND CLINICAL RELEVANCE

Cats with sepsis may have various clinicopathologic abnormalities but are more likely to have a high band neutrophil percentage and hypoalbuminemia than cats with noninfectious SIRS. Plasma interleukin-1β activity and plasma IL-6 and chloride concentrations may be useful prognostic biomarkers for septic cats.

A review of the pathophysiology, classification, and analysis of canine and feline cavitary effusions

Effusion is the abnormal accumulation of fluid within a body cavity that can result from a variety of disease processes. This article reviews the normal production and resorption of body cavity fluid and the pathophysiology of abnormal fluid accumulation. In addition, classification schemes, differential diagnoses, and currently available diagnostic tests for evaluation of effusions are reviewed.

Pleural effusion in the cat: a practical approach to determining aetiology

PRACTICAL RELEVANCE

Diverse disease processes result in sufficient fluid accumulation within the pleural space to cause respiratory compromise. Determining the underlying aetiology is key to appropriate management. This review outlines a practical approach to cases of pleural effusion, focusing on early recognition and confirmation of pleural space disease, stabilisation of the patient and logical diagnostic investigation. It emphasises the importance of a holistic approach, incorporating fluid analysis with other clinical data to determine the underlying aetiology.

CLINICAL CHALLENGES

Cats with pleural effusion often have severe respiratory compromise at presentation. Careful handling and prompt and adequate stabilisation, incorporating supplemental oxygen and therapeutic thoracocentesis, is essential to avoid respiratory failure. The typical, stepwise approach to the case must be adapted and the clinician may have to proceed, at least initially, without the luxury of information gained from a full history and physical examination. The challenge is to juggle stabilisation, localisation and confirmation of pleural effusion, owner communication and minimally invasive examination while remaining vigilant for clues that allow ranking of the differentials to formulate a diagnostic plan.

EVIDENCE BASE

Appropriately designed studies to determine the utility of diagnostic techniques in cases with confirmed aetiology are limited. The evidence supporting this review is grade II, III and IV, comprising a small number of prospective studies, several case series, reviews, extrapolation from other species, pathophysiological justification and combined clinical experience of those working in the field.

Pathogen associated molecular pattern-induced TNF, IL-1β, IL-6 and CXCL-8 production from feline whole blood culture

Whole blood culture (C(wb)) is a method to evaluate leukocyte response to stimuli. We used C(wb) to evaluate the inflammatory response to pathogen associated molecular patterns (PAMPs) in cats. Blood was collected from diluted with RPMI and stimulated with various concentrations of lipopolysaccharide (LPS), lipoteichoic acid (LTA), peptidoglycan (PG) or control (PBS). Multiple concentrations of LPS, LTA and PG significantly stimulated tumor necrosis factor (TNF), interleukin (IL)-1β and CXC chemokine ligand (CXCL)-8 in feline C(wb). All PAMPs failed to stimulate IL-6 production and PG failed to stimulate CXCL-8 production. Lipopolysaccharide was a more potent inducer of IL-1β and CXCL-8 than LTA or PG and LTA is a more potent inducer of CXCL-8 than PG. Based on these data, PAMPs from gram positive and negative bacteria induce TNF, IL-1β and CXCL-8 production in feline whole blood. Cats appear to be relatively more sensitive to gram negative compared to gram positive bacteria.

Evaluation of small-bore wire-guided chest drains for management of pleural space disease

OBJECTIVES

To evaluate the efficacy and practicality of a small-bore wire-guided chest drain for management of pleural space disease in dogs and cats.

MATERIALS AND METHODS

A 14 gauge chest drain was placed using a modified Seldinger technique in animals requiring ongoing management of pleural space disease. A questionnaire was used immediately after placement to collect data regarding the ease of placement, reliability and function of the drain.

RESULTS

Twenty animals were enrolled in which 29 drains were placed. The most common pleural space disease encountered was pyothorax (10 of 20). Sixteen animals required sedation for placement, and 25 of 29 chest drains were inserted at the first attempt. Most drains were placed in less than 10 minutes. The median length of time of catheter use was three days. Few complications were noted during the insertion and throughout the use of the drains. Clinicians rated drain placement as "easy" in 27 of 29 times and the drain function as "good" in 24 of 29 times.

CLINICAL SIGNIFICANCE

Small-bore wire-guided chest drains are an effective alternative to larger gauge drains. Only minor complications were seen during insertion of the chest drains, and their performance was deemed satisfactory in most cases.

Feline pyothorax - new insights into an old problem: part 2. Treatment recommendations and prophylaxis

Until recently, pyothorax in the cat has been generally considered to have a poor prognosis. However, it has become clear that most cats that survive the first 48 h following presentation can be successfully treated with aggressive medical management. In this second part of a two-part review, logical guidelines for the management of the disease are discussed, with particular emphasis on antimicrobial selection. Patient stabilisation and supportive care, techniques for pleural space drainage and lavage and indications for surgery are reviewed.

Medical and surgical management of pyothorax

Pyothorax is the accumulation of septic suppurative inflammation within the pleural cavity. The cause and source of infection in dogs and cats often are unknown. Management of these cases can be challenging, because controversy exists over the best method for treatment. Reported outcomes and recurrence rates vary widely.

Feline pyothorax: a retrospective study of 27 cases in Australia

Pyothorax was diagnosed in 27 cats between 1983 and 2002. In 21 (78%) of the cases, pleural fluid culture and/or cytology was consistent with a mixed anaerobic bacterial infection of oropharyngeal origin. In six cases (22%), infection was caused by unusual pathogens or pathogens of non-oropharyngeal origin, including a Mycoplasma species, Cryptococcus gattii, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus. The overall mortality rate was 22%. Treatment was successful in 18 of 19 cases (95%) where closed thoracostomy tubes were inserted. One case resolved only after thoracotomy. Actinomyces species were isolated in three cases and in contrast to dogs where thoracotomy is recommended, they were resolved with tube thoracostomy. Mechanical complications occurred in 58% of the cats with indwelling chest tubes. Probable mechanisms of pleural space infection were identified in 18 cats (67%) including haematogenous infection (n=1), direct inoculation of bacteria into the pleural space (n=1), intrathoracic oesophageal rupture (n=1) and parapneumonic extension of infection (n=15; 56%). Of the latter, perioperative aspiration was suspected in two cats, parasitic migration in two and antecedent upper respiratory tract infection was implicated in seven. Parapneumonic spread of infection after colonisation and invasion of lung tissue by oropharyngeal flora appears to be the most frequent cause of feline anaerobic polymicrobial pyothorax and contests the widespread belief that direct inoculation of pleural cavity by bite wounds is more common.

Pyothorax in a cat managed by intrathoracic debridement and postoperative ventilatory support

: A domestic-longhair cat presented due to lethargy, dyspnoea and hypersalivation. Radiographic examination revealed a bilateral pleural effusion, which was diagnosed as pyothorax based on cytological examination. Ultrasonographic examination revealed extensive loculations within the thoracic cavity. Exploratory sternotomy, under general anaesthesia, allowed the removal of approximately 100 ml of purulent fluid and debridement of a partially walled-off abscess and necrotic material from the pleural cavity. Postoperative positive-pressure ventilation was required due to severe respiratory depression. Intensive postoperative care, including intensive continuous monitoring, thoracostomy tube drainage and lavage of the pleural cavity and oesophagostomy tube feeding, was performed. Complete resolution of clinical signs had occurred by 15 days postoperatively. Clinical or radiographic abnormalities were not detected at a follow-up examination one year after surgery.

Approach to the patient with respiratory distress

Respiratory emergencies are common presentations to emergency clinicians. Appropriate assessment and timely interventions may be crucial in the stabilization of dyspneic patients. The emergency clinician should be fully prepared and equipped to correctly ascertain and treat the most likely cause of respiratory compromise of a patient. Based on history, signalment, clinical presentation, and brief physical examination findings, the clinician should be able to formulate a plan of action to relieve respiratory distress and communicate with the owner about the diagnostic and therapeutic strategies and overall prognosis of the patient. Prompt recognition of the underlying respiratory disease and complete familiarity with emergency diagnostic and therapeutic procedures can lead to the successful management of many emergency respiratory patients.