Septic peritonitis from pyloric and non-pyloric gastrointestinal perforation: prognostic factors in 44 dogs and 11 cats

Aetiology, clinical parameters and outcome in 113 dogs surgically treated for septic peritonitis (2004-2020)

BACKGROUND

Septic peritonitis (SP) is a common life-threatening condition. The aims of this study were to describe the aetiology, clinicopathological abnormalities, complications, treatment, outcome and prognosis of dogs with SP.

METHODS

Records of 113 dogs diagnosed and surgically treated for SP between 2004 and 2020 were reviewed.

RESULTS

Overall survival rate was 74.3%. Parameters at presentation that were significantly associated with mortality were lateral recumbency (p = 0.001) and elevated respiratory rate (p = 0.045). Hypotension during or after surgery (p < 0.001), liver injury (p < 0.001) and acute kidney injury (p < 0.001) were also more common in non-survivors. The source of contamination, number of surgeries or the location of perforation in cases of gastrointestinal tract perforation were not associated with mortality. Delta glucose (serum vs. abdominal) was available in 36 out of 113 dogs and the difference was more than 20 mg/dl in only 22 of out 36 (61.1%) cases.

CONCLUSION

Liver and kidney injuries play a role in mortality, and early diagnosis and intervention are recommended to prevent multiple organ dysfunction and death. The reported high sensitivity of delta glucose is questionable in diagnosis of SP.

Association of the origin of contamination and species of microorganisms with short-term survival in dogs with septic peritonitis

OBJECTIVE

To assess the association between anatomical location of contamination and mortality in dogs with gastrointestinal and biliary origin of septic peritonitis.

METHODS

Medical records at two private referral hospitals between 2003 and 2020 were retrospectively reviewed. Cases were included if the origin of contamination was confirmed intraoperatively within the gastrointestinal or biliary tract. Cases were excluded if the dog died or was euthanized intraoperatively or where the data regarding the origin of contamination were not available. The association of anatomical origin with survival was assessed specifying the locations as stomach, small intestine, large intestine and biliary tract. The gastrointestinal tract origin was further subdivided into pylorus, nonpylorus, duodenum, jejunum, ileum, caecum and colon.

RESULTS

The overall survival rate was 75.9% (n = 44/58). There were no significant differences in survival among different anatomical origins of contaminations before or after subdivision (P = 0.349 and 0.832, respectively). Also, there was no association between isolated microorganism species in microbiological culture and the anatomical origin (P = 0.951) and the microorganism species was not associated with survival (P = 0.674).

CONCLUSIONS

There was no association between anatomical location of leakage, microorganism species and survival although further studies are warranted to analyse the relationships between anatomical leakage site and microorganism species as well as microorganism species and mortality.

Accuracy of radiographic diagnosis of pneumoperitoneum secondary to gastrointestinal perforation in dogs and cats

BACKGROUND

Radiography is commonly included in the diagnostic investigation of animals with suspected gastrointestinal perforation and resultant pneumoperitoneum. This study aimed to (1) identify the accuracy of radiographic diagnosis of pneumoperitoneum and (2) determine if observer experience affected accuracy.

METHODS

This was a retrospective case-controlled study evaluating abdominal radiographs of dogs and cats with surgical confirmation of gastrointestinal perforation or peritonitis without pneumoperitoneum. Radiographs were reviewed by a radiologist, an imaging resident, a general practitioner and a veterinary student.

RESULTS

Radiographs from 60 dogs and eight cats were evaluated; 34 animals had confirmed perforation. Accuracy was fair to excellent for all observers: student 61.8%, general practitioner 70.6%, resident 85.3% and radiologist 83.8%. There was no significant difference in sensitivity between observers (all 70.6%-85.3%); however, there was a significant difference in specificity between both the resident (91.2%) and radiologist (91.2%) compared to the student (52.9%) (p < 0.001) and the general practitioner (55.9%) (p = 0.002). Overall, there was slight to substantial agreement between observers (κ = 0.28-0.73), with the highest being between the radiologist and resident.

CONCLUSION

Abdominal radiography, when interpreted by veterinarians with differing experience, has variable accuracy for diagnosis of pneumoperitoneum for animals in this study. Further studies are needed to determine if these results are applicable for other populations of animals with pneumoperitoneum.

Primary repair of nonsteroidal anti-inflammatory drug-associated full thickness gastrointestinal ulcers in 11 dogs

OBJECTIVE

To report the outcomes of dogs that underwent primary repair of gastroduodenal perforations associated with the administration of nonsteroidal anti-inflammatory drugs (NSAID). A secondary objective was to identify clinicopathological findings that predisposed dogs to postoperative death.

STUDY DESIGN

Retrospective study.

ANIMALS

Eleven dogs with complete gastric or duodenal perforation related to administration of an NSAID that underwent primary surgical repair.

METHODS

Medical records were reviewed for dogs that presented with peritonitis due to a complete gastroduodenal perforation while receiving NSAIDs between November, 2011 and January, 2021. Data collected included patient characteristics, clinical signs, clinicopathological results, surgical details, and postoperative management and outcome.

RESULTS

All dogs were large breeds (mean weight 42 kg; range 22-75 kg), with a mean age of 7.35 years. Nine dogs from a total of 11 (82 %) received a concurrent corticosteroid and NSAID, or a higher dose/frequency/length of NSAID administration than recommended by the manufacturer. All gastroduodenal perforations were found in the upper gastrointestinal tract. Eight of 11 (73%) dogs survived to discharge. The median postoperative duration of follow up was 444 days (range 2-1460 days). No association was detected between ulcer size or location and mortality.

CONCLUSION

Most dogs who underwent primary repair of complete gastroduodenal ulcers survived. Gastroduodenal perforations were generally due to the administration of higher or longer doses of NSAIDs, or concurrent administration of another NSAID or corticosteroid.

CLINICAL SIGNIFICANCE

Primary closure may be associated with a high success rate in dogs with full thickness gastroduodenal ulcers.

Gastric or duodenal perforation and secondary septic peritonitis following therapeutic nonsteroidal anti-inflammatory drug administration

OBJECTIVE

To report which nonsteroidal anti-inflammatory drugs (NSAIDs) were associated with gastric or duodenal perforation (GDP) in dogs presented to a university teaching hospital and to report the frequency of prescription of NSAIDs by the corresponding referring veterinary community during the same time period.

DESIGN

Retrospective cohort study of dogs from January 2007 to March 2020.

SETTING

Single university teaching hospital.

ANIMALS

A total of 30 dogs met inclusion criteria.

MEASUREMENTS AND MAIN RESULTS

Four dogs were administered more than 1 NSAID within 7 days of GDP, 3 dogs received a combination of an NSAID and a corticosteroid, and 1 dog received 2 NSAIDs and a corticosteroid. Four dogs received an overdose of an NSAID. One dog received an overdose of 1 NSAID and received an additional NSAID at the labeled dose within 7 days of GDP. Eighteen dogs received only 1 NSAID at the labeled dose. In these 18 dogs, meloxicam was administered in 44.4% (8/18), firocoxib in 27.8% (5/18), deracoxib in 16.7% (3/18), and piroxicam in 11.1% (2/18). One hundred and sixty surveys on NSAID prescribing practice were returned. Carprofen was the most commonly prescribed NSAID (70.6%), followed by meloxicam (10.6%), deracoxib (8.4%), firocoxib (7.8%), aspirin (1.5%), and other (0.9%).

CONCLUSIONS

NSAID administration, even at labeled doses, appears to be a precipitating factor for GDP. Despite carprofen being the most frequently prescribed NSAID over the study period, no case of GDP received it as a single therapeutic agent. Further prospective evaluation is needed to verify these findings.

Effect of antimicrobial administration on fecal microbiota of critically ill dogs: dynamics of antimicrobial resistance over time

Background

Multidrug resistance in companion animals poses significant risks to animal and human health. Prolonged antimicrobial drug (AMD) treatment in animals is a potential source of selection pressure for antimicrobial resistance (AMR) including in the gastrointestinal microbiota. We performed a prospective study of dogs treated for septic peritonitis, pyometra, or bacterial pneumonia and collected repeated fecal samples over 60 days. Bacterial cultures and direct molecular analyses of fecal samples were performed including targeted resistance gene profiling.

Results

Resistant Escherichia coli increased after 1 week of treatment (D1:21.4% vs. D7:67.9% P < 0.001) and returned to baseline proportions by D60 (D7:67.9% vs D60:42.9%, P = 0.04). Dogs with septic peritonitis were hospitalized significantly longer than those with pneumonia or pyometra. Based on genetic analysis, Simpson’s diversity index significantly decreased after 1 week of treatment (D1 to D7, P = 0.008), followed by a gradual increase to day 60 (D1 and D60, P = 0.4). Detection of CTX-M was associated with phenotypic resistance to third-generation cephalosporins in E. coli (OR 12.1, 3.3–68.0, P < 0.001). Lincosamide and macrolide-resistance genes were more frequently recovered on days 14 and 28 compared to day 1 (P = 0.002 and P = 0.004 respectively).

Conclusion

AMR was associated with prescribed drugs but also developed against AMDs not administered during the study. Companion animals may be reservoirs of zoonotic multidrug resistant pathogens, suggesting that veterinary AMD stewardship and surveillance efforts should be prioritized.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s42523-022-00178-9.

Use of selected biochemical indices in blood/peritoneal effusion in diagnostics of gastrointestinal tract damage in dogs

This study evaluated selected biochemical indices in blood/peritoneal fluid in dogs with and without gastrointestinal tract damage. Blood and peritoneal fluid samples of 29 dogs presented to the Small Animal Clinic at the University of Veterinary and Pharmaceutical Sciences Brno were obtained as a part of the diagnostic approach and were subsequently biochemically analysed. The biochemical indices analysed were potassium, total protein, glucose, lactate and creatinine. Effusion-to-blood concentration ratios of selected indices were obtained for higher data validity and this ratio was then compared between two groups: patients with gastrointestinal tract damage and patients without gastrointestinal tract damage. There were 11 dogs in the study group of patients with gastrointestinal tract damage and 18 dogs in the study group of patients without gastrointestinal tract damage. Subsequent statistical data analysis did not show any significant difference between these two groups in any of the selected indices. According to our study results, selected biochemical indices cannot be considered as decisive for diagnosing gastrointestinal tract damage.

Serial analysis of blood biomarker concentrations in dogs with pneumonia, septic peritonitis, and pyometra

BACKGROUND

Prolonged antimicrobial drug (AMD) treatment is associated with antimicrobial resistance development. Biomarker measurement may aid treatment decision-making.

OBJECTIVES

Investigate temporal changes in blood biomarker concentrations in dogs undergoing treatment for pulmonary and intra-abdominal infections; compare time to biomarker concentration normalization with duration of clinician-directed AMD treatment.

ANIMALS

Forty-two client-owned dogs with pneumonia (n = 22), septic peritonitis (n = 10), or pyometra (n = 10).

METHODS

Plasma concentrations of C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin, procalcitonin, nucleosomes, cell-free DNA (cfDNA), high-mobility group box-1 (HMGB1), CC-motif chemokine ligand-2 (CCL2), CXC-motif chemokine ligand-8 (CXCL8), and keratinocyte chemoattractant-like (KC-Like) were quantitated in samples collected on days 1, 3, 7, 14, 28, and 60. Treatment was directed by clinicians blinded to biomarker concentrations.

RESULTS

Concentrations of CCL2, CRP, and KC-Like were maximal on D1, concentrations of SAA, cfDNA, HMGB1, and nucleosomes were maximal on D3 and haptoglobin concentrations were maximal on D7. These maximal concentrations were significantly different from those on D60. Concentrations of CRP and SAA decreased by 80% from peak and into respective reference intervals before AMDs were discontinued. For CRP, the median (interquartile range [IQR]) times to 20% peak and normal were 7 (6-9) and 7 (6-12) days, respectively, and for SAA they were 4 (4, 5) and 6 (5-8) days, respectively, compared to a median (IQR) duration of AMD prescribing of 16 (12-23) days (all P < .0001).

CONCLUSIONS AND CLINICAL IMPORTANCE

Biomarker concentrations normalized within 7 to 14 days. Serial measurements of CRP and SAA might aid identification of disease resolution and could help guide AMD prescription decision-making.

A feasibility study investigating the utility of a point-of-care rapid immunoassay for detecting septic peritoneal effusion in dogs

OBJECTIVE

To determine the sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy of a point-of-care urine bacterial rapid immunoassay (RIA) for a diagnosis of septic peritonitis, compared to more traditional diagnostic tools, such as cytology and bacterial culture.

DESIGN

Prospective, cross-sectional feasibility study conducted from October 2016 to June 2017.

SETTING

Four locations within a private practice referral hospital.

ANIMALS

Sixty-four dogs with peritoneal effusion of any etiology were enrolled. Four dogs were excluded due to absent RIA or bacterial culture results. Two additional dogs were excluded because of an inability to definitively classify them as having septic peritonitis.

INTERVENTIONS

Abdominocentesis was performed to obtain peritoneal effusion samples for aerobic and anaerobic bacterial culture, cytology, and RIA. Cytological slides were evaluated by a clinical pathologist following enrollment.

MEASUREMENTS AND MAIN RESULTS

Fifty-eight dogs were included in the study, 8 of which were classified as having septic peritonitis. Compared to final diagnosis of septic peritonitis, RIA had a low PPV (36.8%) but good NPV (97.4%) and was 77.5% accurate. SN of RIA (87.5%) to diagnose septic peritonitis was similar to cytology (85.7%) and bacterial culture (87.5%); however, SP was lower (76%, 100%, and 98%, respectively). Cytology had the best overall predictive values and accuracy for diagnosing septic peritonitis (PPV 100%, NPV 97.9%, and accuracy 98%) compared to RIA and bacterial culture.

CONCLUSIONS

RIA testing was similarly sensitive in identifying septic peritonitis compared to cytology and bacterial culture but was not very specific or accurate. As a stand-alone test, RIA commonly had false-positive test results, making it unreliable in identifying septic peritonitis. Cytology was the most accurate diagnostic test and had no false-positive results. Further investigation with a larger sample size and prevalence of septic peritonitis may prove beneficial.

A comparative time-dependent study of hematology, serum gastrin concentrations, and gastroscopic assessment of meloxicam-induced gastric ulceration in dogs

Background

Diagnosis of gastric ulcers by methods other than gastroscopy in dogs has been problematic for many years and biomarkers such as serum gastrin (SG) concentrations have been introduced as a noninvasive way to evaluate gastric diseases.

Objectives

To determine the time course changes in hematology, SG concentrations, and gastroscopic images of meloxicam‐induced gastric ulceration in dogs and identify a relationship between SG and gastroscopic image analysis in a clinical setting.

Animals

Fifteen crossbreed dogs.

Methods

Two groups: control (n = 5) and meloxicam‐treated (n = 10). The meloxicam‐treated group received meloxicam 0.2 mg/kg PO for 15 days. Clinical signs, hematology, SG, and image analysis (PI, pixel intensity; ID, integrated density; RA, relative area; and UI, ulcer index) of the gastroscopic examination were evaluated across time (T5, time 5 day; T10, time 10 day; and T15, time 15 day).

Results

Significant changes were observed among 3 time points and between the 2 groups in terms of SG, hematology, and gastroscopic image analysis. In the meloxicam‐treated group, decreases in hemoglobin concentration, red blood cell count and packed cell volume at T10 and T15 (P = .0001) were observed, whereas SG, ID, and UI increased over time (P < .0001). The PI decreased significantly (P = .0001) in the meloxicam‐treated group compared to controls. Significant correlations were found between SG and PI, and ID and ulcer area (r = −0.89, 0.81, 0.64), respectively.

Conclusion and Clinical Importance

Gastroscopy is the gold standard for early descriptive diagnosis of gastric ulcerations in dogs, and SG is a good indicator for meloxicam‐induced gastric ulcers in dogs and can predict the gastroscopic score of the lesion.

Outcome following surgery to treat septic peritonitis in 95 cats in the United Kingdom

OBJECTIVES

To review the cause, management and outcome in cats with septic peritonitis within the United Kingdom (2008 to 2018) and to identify if previously identified prognostic factors were associated with survival in this population.

MATERIALS AND METHODS

Clinical records from 10 referral hospitals in United Kingdom were reviewed. Data collected included signalment, clinicopathological data and management techniques. Serum albumin, glucose, lactate and ionised calcium concentration; presence of intraoperative hypotension and correct empirical antibiosis were analysed via logistic regression for association with survival.

RESULTS

Ninety-five cats were included. The overall survival rate was 66%. Lethargy (89%) and anorexia (75%) were the most common clinical signs, with abdominal pain and vomiting in 44% and 27% of cases, respectively. Gastro-intestinal leakage was the most common source of contamination. The presence of an abdominal mass on clinical examination was not strongly predictive of the presence of neoplasia on histology and did not confer a worse prognosis. Cats presenting with dehiscence of a previous enterotomy/enterectomy did not have a worse prognosis than those presenting with other aetologies. Intraoperative hypotension (adjusted odds ratio 0.173, 95% confidence intervals 0.034 to 0.866, P=0.033) was associated with non-survival. Cats that survived beyond 1 day postoperatively had an improved likelihood of survival (87.5%). All cats that survived beyond 6 days were successfully discharged.

CLINICAL SIGNIFICANCE

This study describes the largest group of cats with septic peritonitis with an overall survival rate of 66%. The presence of an abdominal mass on clinical examination or having dehiscence of a previous gastrointestinal surgery did not confer a worse prognosis.

Diagnostic utility of abdominal ultrasound for detecting non-perforated gastroduodenal ulcers in dogs

BACKGROUND

Abdominal ultrasound is frequently used to detect non-perforated gastroduodenal ulcers in dogs. Studies assessing the diagnostic utility of abdominal ultrasound for the detection of non-perforated gastroduodenal ulcers have yielded mixed results. No studies to date have investigated the effects of patient bodyweight, breed, sex, age, ulcer aetiology (neoplastic or inflammatory) or location on the diagnostic accuracy of abdominal ultrasound.

METHODS

Retrospective, multicentre study to evaluate the diagnostic utility of abdominal ultrasonography for the diagnosis of non-perforated gastroduodenal ulceration in dogs.

RESULTS

Sixty-one dogs met the inclusion criteria. Ulcers were detected during ultrasound examination in 18 of 61 dogs, yielding a sensitivity of 29.5% (95% confidence interval 18.8%-42.7%). Ulcers in the pyloric region were detected more frequently than those in the duodenum; however, location was not significantly associated with the ability of ultrasound to detect lesions (p = 0.41). No associations were identified between the ability of ultrasound to detect an ulcer and patient bodyweight (p = 0.45), breed (p = 0.98), sex (p = 0.90), age (p = 0.94), and neoplastic versus inflammatory nature of ulcerative lesions (p = 0.93).

CONCLUSION

The diagnostic utility of ultrasound as the sole modality for the detection of non-perforated gastroduodenal mucosal ulceration is poor. The authors therefore recommend the use of additional modalities when ulcerative lesions are suspected.

Fluid Resuscitation for Refractory Hypotension

Hypotension is a common occurrence, especially in anesthetized patients and in critical patients suffering from hypovolemia due to shock and sepsis. Hypotension can also occur in normovolemic animals, anesthetized or conscious, under conditions of vasodilation or decreased cardiac function. The main consequence of hypotension is decreased organ perfusion and tissue injury/dysfunction. In the human literature there is no consensus on what is the threshold value for hypotension, and ranges from < 80 to < 100 mmHg for systolic blood pressure and from < 50 to < 70 mmHg for mean arterial blood pressure have been referenced for intraoperative hypotension. In veterinary medicine, similar values are referenced, despite marked differences in normal arterial blood pressure between species and with respect to humans. Therapeutic intervention involves fluid therapy to normalize volemia and use of sympathomimetics to enhance cardiac function and regulate peripheral vascular resistance. Despite these therapeutic measures, there is a subset of patients that are seemingly refractory and exhibit persistent hypotension. This review covers the physiological aspects that govern arterial blood pressure control and blood flow to tissues/organs, the pathophysiological mechanisms involved in hypotension and refractory hypotension, and therapeutic considerations and expectations that include proper interpretation of cardiovascular parameters, fluid recommendations and therapy rates, use of sympathomimetics and vasopressors, and newer approaches derived from the human literature.

Presumptive Lornoxicam Intoxication in Four Dogs

Lornoxicam is a nonsteroidal anti-inflammatory drug extensively used in human medicine, which is not approved for canine use. Lornoxicam intoxication has been rarely reported in dogs. Four dogs of various breeds, aged 7 months to 10 years, were admitted with a recent history of melena, anorexia and depression, occurring 1-4 days after the ingestion of lornoxicam (dose range: 0.53-2.7 [median 1.17] mg/kg). No clinically relevant comorbidities were documented, but low doses of prednisolone had been given in 3 of the dogs, in close temporal association with lornoxicam. Major clinical and clinicopathologic findings on admission included mucosal pallor, melena, depression, severe anemia, neutrophilic leucocytosis, and panhypoproteinemia. Perforated pyloric and duodenal ulcers were documented in 3 dogs by exploratory celiotomy or postmortem. Prolonged hospitalization (5-20 days) with extensive supportive care and multiple blood transfusions was required in 3 of the 4 dogs who survived to discharge. Lornoxicam ingestion may cause protracted and severe gastrointestinal tract injury and bleeding, blood loss anemia, panhypoproteinemia, and perforated gastrointestinal ulcers, associated with significant morbidity and mortality in dogs.

Effect of presurgical storage conditions on leakage pressures of enterotomy sites closed with unidirectional barbed suture material in fresh, chilled, and frozen-thawed cadaveric canine jejunal specimens

OBJECTIVE

To evaluate the effect of presurgical storage conditions on leakage pressures of enterotomy sites closed with unidirectional barbed suture material in fresh, chilled, and frozen-thawed cadaveric canine jejunal specimens.

SAMPLE

36 grossly normal jejunal segments obtained from 4 dog cadavers.

PROCEDURES

9 jejunal segments were harvested immediately from each euthanized dog and randomly assigned to be tested within 4 hours after collection (fresh segments), stored at 4°C for 24 hours before testing (chilled segments), or stored at -20°C for 7 days and thawed at 21°C for 6 hours before testing (frozen-thawed segments). For leakage pressure testing, a 3-cm-long antimesenteric enterotomy was performed and repaired with 3-0 unidirectional barbed suture material in a simple continuous pattern in each segment. Time to complete the enterotomy, initial leakage pressure, maximum intraluminal pressure, and leakage location were recorded for each segment.

RESULTS

Mean ± SD initial leakage pressure for fresh, chilled, and frozen-thawed segments was 52.8 ± 14.9 mm Hg, 51.8 ± 11.9 mm Hg, and 33.3 ± 7.7 mm Hg, respectively. Frozen-thawed segments had significantly lower mean initial leakage pressure, compared with findings for fresh or chilled segments. Time to complete the enterotomy, maximum intraluminal pressure, and leakage location did not differ among groups.

CONCLUSIONS AND CLINICAL RELEVANCE

Leak pressure testing of cadaveric jejunal segments that are fresh or chilled at 4°C for 24 hours is recommended for enterotomy studies involving barbed suture material in dogs. Freezing and thawing of cadaveric jejunal tissues prior to investigative use is not recommended because leak pressure data may be falsely low.

Biomarker Guided Diagnosis of Septic Peritonitis in Dogs

Septic peritonitis (SP) is common in dogs and is associated with high mortality. Early recognition is essential to maximizing survival and may be aided by biomarker measurement. The present study aimed to evaluate the ability of biomarkers to discriminate septic peritonitis from non-septic ascites (NSA). Eighteen dogs with SP and 19 age-matched controls with NSA were enrolled. Contemporaneous blood and peritoneal effusion samples were obtained. Concentrations of cell-free DNA (cfDNA), cytokines, glucose, lactate, N-terminal pro-C-type natriuretic peptide (NT-proCNP), nucleosomes, and procalcitonin (PCT) were measured using commercial reagents and assays. Paired biomarker concentrations were compared with the Wilcoxon matched-pairs signed rank test, and biomarker concentrations between groups were compared with the Mann-Whitney U-test. P-values were adjusted for multiple comparisons using the Bonferroni correction. Receiver operating characteristic curves were generated to assess the ability of the above biomarkers to discriminate SP from NSA. Dogs with SP had significantly greater blood CCL2 concentrations than dogs with NSA (P = 0.032). Dogs with SP had significantly greater effusion CCL2, IL-6, IL-10, and lactate concentrations than dogs with NSA (P ≤ 0.0121). Blood-effusion concentration gradients of CCL2, glucose, IL-6, IL-10, and lactate were significantly different in dogs with SP compared to dogs with NSA (P ≤ 0.0165). Effusion lactate concentration had the highest AUROC value (0.866, 95% CI 0.751–0.980, P = 0.0001), although other biomarkers performed similarly. An effusion lactate concentration of 4.2 mmol/L was 72.2% (95% CI 46.5–90.3%) sensitive and 84.2% (95% CI 60.4–96.6%) specific for the diagnosis of SP.

Evaluation of platelet function using multiple electrode platelet aggregometry in dogs with septic peritonitis

OBJECTIVE

To assess platelet function via multiple electrode platelet aggregometry (MEPA) in dogs with septic peritonitis and in healthy dogs. The secondary aim was to determine if there is prognostic significance to changes in platelet function observed in septic dogs.

DESIGN

Prospective, observational cohort study conducted from January 2012 to March 2014.

SETTING

University teaching hospital.

ANIMALS

Twenty dogs with septic peritonitis and 23 healthy dogs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

MEPA using arachidonic acid, adenosine diphosphate, and collagen (COL) as agonists was measured within 24 hours of diagnosis of sepsis. Compared to healthy dogs, platelet aggregation was reduced in dogs with septic peritonitis for all agonists (P < 0.01). Overall mortality rate was 40%. MEPA in response to COL was significantly reduced in nonsurvivors compared to survivors (P = 0.019). Using receiver-operating characteristic curve statistics, a COL-activated MEPA less than 43.5 aggregation units had a sensitivity and specificity of 85.7% and 90.9%, respectively, for predicting nonsurvival in dogs with septic peritonitis.

CONCLUSIONS

Circulating platelets from dogs with septic peritonitis have diminished aggregation in response to multiple platelet agonists. MEPA may serve as an assessment tool for illness severity in this patient population.

Increased ratio of peritoneal effusion-to-serum potassium concentration in a dog with gastric perforation

OBJECTIVE

To describe the clinical and laboratory findings of a dog with gastric perforation, resulting in a markedly increased peritoneal effusion-to-serum potassium ratio.

CASE SUMMARY

A 6-year-old mixed breed neutered male dog presented with a right femoral fracture after being hit by car. The fracture was repaired surgically. Four days postoperatively, the dog developed peritoneal effusion, confirmed with ultrasonography. Peritoneal effusion analysis and serum biochemistry, performed concurrently, showed blood-to-effusion glucose difference >1.1 mmol/L [>20 mg/dL], suggesting the effusion was septic. The effusion-to-serum creatinine ratio was mildly increased (1.36) and the effusion-to-serum potassium ratio was markedly increased (>2.67). Combined, these findings were suggestive of a septic uroabdomen. A positive contrast retrograde urethrocystography did not reveal urine leakage from the lower urinary tract. An exploratory laparotomy revealed a gastric perforation in the pyloric area and an intact urinary tract.

NEW INFORMATION PROVIDED

Gastric perforation should be considered a differential diagnosis in dogs with an increased peritoneal effusion to serum potassium ratio.