2024 RECOVER Guidelines: Updated treatment recommendations for CPR in dogs and cats.

OBJECTIVE: After the 2012 Reassessment Campaign on Veterinary Resuscitation (RECOVER) CPR Guidelines, this is an update of evidence-based consensus guidelines for Basic Life Support (BLS), advanced life support (ALS), and periarrest monitoring. DESIGN: These RECOVER CPR Guidelines were generated using a modified version of the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system for evidence evaluation and translation of this evidence into clear and actionable clinical instructions. Prioritized clinical questions in the Population, Intervention, Comparator, and Outcome (PICO) format were used as the basis to conduct systematic literature searches by information specialists, to extract information from relevant publications, to assess this evidence for quality, and finally to translate the findings into treatment recommendations. These recommendations were reviewed by the RECOVER writing group and opened for comment by veterinary professionals for 4 weeks. SETTING: Transdisciplinary, international collaboration in university, specialty, and emergency practice. RESULTS: A total of 40 worksheets were prepared to evaluate questions across the 3 domains of BLS, ALS and Monitoring, resulting in 90 individual treatment recommendations. High-dose epinephrine is no longer recommended, and atropine, if used, is only administered once. Bag-mask ventilation is prioritized over mouth-to-nose ventilation in nonintubated animals. In addition, an algorithm for initial assessment, an updated CPR algorithm, a rhythm diagnosis tool, and an updated drug dosing table are provided. CONCLUSIONS: While the majority of the BLS and ALS recommendations remain unchanged, some noteworthy changes were made due to new evidence that emerged over the past 10 years. Indirectness of evidence remains the largest impediment to the certainty of guidelines formulation and underscores an urgent need for more studies in the target species of dogs and cats.

2024 RECOVER Guidelines: Basic Life Support. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR.

OBJECTIVE: To systematically review evidence and devise treatment recommendations for basic life support (BLS) in dogs and cats and to identify critical knowledge gaps. DESIGN: Standardized, systematic evaluation of literature pertinent to BLS following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by 2 Evidence Evaluators, and findings were reconciled by BLS Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk to benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization. SETTING: Transdisciplinary, international collaboration in university, specialty, and emergency practice. RESULTS: Twenty questions regarding animal position, chest compression point and technique, ventilation strategies, as well as the duration of CPR cycles and chest compression pauses were examined, and 32 treatment recommendations were formulated. Out of these, 25 addressed chest compressions and 7 informed ventilation during CPR. The recommendations were founded predominantly on very low quality of evidence and expert opinion. These new treatment recommendations continue to emphasize the critical importance of high-quality, uninterrupted chest compressions, with a modification suggested for the chest compression technique in wide-chested dogs. When intubation is not possible, bag-mask ventilation using a tight-fitting facemask with oxygen supplementation is recommended rather than mouth-to-nose ventilation. CONCLUSIONS: These updated RECOVER BLS treatment recommendations emphasize continuous chest compressions, conformation-specific chest compression techniques, and ventilation for all animals. Very low quality of evidence due to absence of clinical data in dogs and cats consistently compromised the certainty of recommendations, emphasizing the need for more veterinary research in this area.

2024 RECOVER Guidelines: Advanced Life Support. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR.

OBJECTIVE: To systematically review the evidence and devise clinical recommendations on advanced life support (ALS) in dogs and cats and to identify critical knowledge gaps. DESIGN: Standardized, systematic evaluation of literature pertinent to ALS following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by Evidence Evaluators, and findings were reconciled by ALS Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk:benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization. SETTING: Transdisciplinary, international collaboration in university, specialty, and emergency practice. RESULTS: Seventeen questions pertaining to vascular access, vasopressors in shockable and nonshockable rhythms, anticholinergics, defibrillation, antiarrhythmics, and adjunct drug therapy as well as open-chest CPR were reviewed. Of the 33 treatment recommendations formulated, 6 recommendations addressed the management of patients with nonshockable arrest rhythms, 10 addressed shockable rhythms, and 6 provided guidance on open-chest CPR. We recommend against high-dose epinephrine even after prolonged CPR and suggest that atropine, when indicated, is used only once. In animals with a shockable rhythm in which initial defibrillation was unsuccessful, we recommend doubling the defibrillator dose once and suggest vasopressin (or epinephrine if vasopressin is not available), esmolol, lidocaine in dogs, and/or amiodarone in cats. CONCLUSIONS: These updated RECOVER ALS guidelines clarify the approach to refractory shockable rhythms and prolonged CPR. Very low quality of evidence due to absence of clinical data in dogs and cats continues to compromise the certainty with which recommendations can be made.

2024 RECOVER Guidelines: Methods, evidence identification, evaluation, and consensus process for development of treatment recommendations.

OBJECTIVE: To describe the methodology used by the Reassessment Campaign on Veterinary Resuscitation (RECOVER) to re-evaluate the scientific evidence relevant to CPR in small and large animals, to newborn resuscitation, and to first aid and to formulate the respective consensus-based clinical guidelines. DESIGN: This report describes the evidence-to-guidelines process employed by RECOVER that is based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach and includes Information Specialist-driven systematic literature search, evidence evaluation conducted by more than 200 veterinary professionals, and provision of clinical guidelines in the domains of Preparedness and Prevention, Basic Life Support, Advanced Life Support, Post-cardiac Arrest Care, Newborn Resuscitation, First Aid, and Large Animal CPR. SETTING: Transdisciplinary, international collaboration in academia, referral practice, and general practice. RESULTS: For this update to the RECOVER 2012 CPR guidelines, we answered 135 Population, Intervention, Comparator, and Outcome (PICO) questions with the help of a team of Domain Chairs, Information Specialists, and more than 200 Evidence Evaluators. Most primary contributors were veterinary specialists or veterinary technician specialists. The RECOVER 2024 Guidelines represent the first veterinary application of the GRADE approach to clinical guideline development. We employed an iterative process that follows a predefined sequence of steps designed to reduce bias of Evidence Evaluators and to increase the repeatability of the quality of evidence assessments and ultimately the treatment recommendations. The process also allowed numerous important knowledge gaps to emerge that form the foundation for prioritizing research efforts in veterinary resuscitation science. CONCLUSIONS: Large collaborative, volunteer-based development of evidence- and consensus-based clinical guidelines is challenging and complex but feasible. The experience gained will help refine the process for future veterinary guidelines initiatives.

2024 RECOVER Guidelines: Monitoring. Evidence and knowledge gap analysis with treatment recommendations for small animal CPR.

OBJECTIVE: To systematically review evidence on and devise treatment recommendations for patient monitoring before, during, and following CPR in dogs and cats, and to identify critical knowledge gaps. DESIGN: Standardized, systematic evaluation of literature pertinent to peri-CPR monitoring following Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. Prioritized questions were each reviewed by Evidence Evaluators, and findings were reconciled by Monitoring Domain Chairs and Reassessment Campaign on Veterinary Resuscitation (RECOVER) Co-Chairs to arrive at treatment recommendations commensurate to quality of evidence, risk:benefit relationship, and clinical feasibility. This process was implemented using an Evidence Profile Worksheet for each question that included an introduction, consensus on science, treatment recommendations, justification for these recommendations, and important knowledge gaps. A draft of these worksheets was distributed to veterinary professionals for comment for 4 weeks prior to finalization. SETTING: Transdisciplinary, international collaboration in university, specialty, and emergency practice. RESULTS: Thirteen questions pertaining to hemodynamic, respiratory, and metabolic monitoring practices for identification of cardiopulmonary arrest, quality of CPR, and postcardiac arrest care were examined, and 24 treatment recommendations were formulated. Of these, 5 recommendations pertained to aspects of end-tidal CO2 (ETco2) measurement. The recommendations were founded predominantly on very low quality of evidence, with some based on expert opinion. CONCLUSIONS: The Monitoring Domain authors continue to support initiation of chest compressions without pulse palpation. We recommend multimodal monitoring of patients at risk of cardiopulmonary arrest, at risk of re-arrest, or under general anesthesia. This report highlights the utility of ETco2 monitoring to verify correct intubation, identify return of spontaneous circulation, evaluate quality of CPR, and guide basic life support measures. Treatment recommendations further suggest intra-arrest evaluation of electrolytes (ie, potassium and calcium), as these may inform outcome-relevant interventions.

Prevalence and factors associated with initial and subsequent shockable cardiac arrest rhythms and their association with patient outcomes in dogs and cats undergoing cardiopulmonary resuscitation: A RECOVER registry study.

OBJECTIVE: To report the prevalence of initial shockable cardiac arrest rhythms (I-SHKR), incidence of subsequent shockable cardiac arrest rhythms (S-SHKR), and factors associated with I-SHKRs and S-SHKRs and explore their association with return of spontaneous circulation (ROSC) rates in dogs and cats undergoing CPR. DESIGN: Multi-institutional prospective case series from 2016 to 2021, retrospectively analyzed. SETTING: Eight university and eight private practice veterinary hospitals. ANIMALS: A total of 457 dogs and 170 cats with recorded cardiac arrest rhythm and event outcome reported in the Reassessment Campaign on Veterinary Resuscitation CPR registry. MEASUREMENTS AND MAIN RESULTS: Logistic regression was used to evaluate association of animal, hospital, and arrest variables with I-SHKRs and S-SHKRs and with patient outcomes. Odds ratios (ORs) were generated, and significance was set at P < 0.05. Of 627 animals included, 28 (4%) had I-SHKRs. Odds for I-SHKRs were significantly higher in animals with a metabolic cause of arrest (OR 7.61) and that received lidocaine (OR 17.50) or amiodarone (OR 21.22) and significantly lower in animals experiencing arrest during daytime hours (OR 0.22), in the ICU (OR 0.27), in the emergency room (OR 0.13), and out of hospital (OR 0.18) and that received epinephrine (OR 0.19). Of 599 initial nonshockable rhythms, 74 (12%) developed S-SHKRs. Odds for S-SHKRs were significantly higher in animals with higher body weight (OR 1.03), hemorrhage (OR 2.85), or intracranial cause of arrest (OR 3.73) and that received epinephrine (OR 11.36) or lidocaine (OR 18.72) and significantly decreased in those arresting in ICU (OR 0.27), emergency room (OR 0.29), and out of hospital (OR 0.38). Overall, 171 (27%) animals achieved ROSC, 81 (13%) achieved sustained ROSC, and 15 (2%) survived. Neither I-SHKRs nor S-SHKRs were significantly associated with ROSC. CONCLUSIONS: I-SHKRs and S-SHKRs occur infrequently in dogs and cats undergoing CPR and are not associated with increased ROSC rates.

Cerebro-Cardiopulmonary Resuscitation and Postarrest Care in Exotic Animal Critical Care.

Evidence-based recommendations for performing cardiopulmonary resuscitation (CPR) in domestic species provide a foundation for application to nondomestic species. The exotic and zoo practitioner must consider human safety, species anatomy, physiology, and special techniques for performing CPR. Having the hospital and team prepared and trained for a CPR response can improve outcomes. Basic life support includes various techniques for chest compressions and ventilation support. Advanced life support includes means of intravascular and intraosseous access, rescue drug administration, and consideration of the patient presenting circumstances. Team debriefs and support for mental wellness are useful to optimize performance and maintain team resiliency through CPR events.

Open-heart surgery using Del-Nido cardioplegia in two dogs: partial atrioventricular septal defect and mitral repair.

Del-Nido cardioplegia (DNc) is a single-dose cardioplegia that is widely used in human medicine because of its long duration. In this report, we describe two cases of open-heart surgery with cardiopulmonary bypass (CPB) using DNc. One dog was diagnosed with partial atrioventricular septal defect, and the other dog was diagnosed with myxomatous mitral valve disease stage D. Both dogs were treated with open-heart surgery with DNc to induce temporary cardiac arrest. No complications from DNc were observed, and the patients were discharged. Veterinary heart surgeons should consider DNc as an option for temporary cardiac arrest during open-heart surgery with CPB.

Clinical presentation, diagnosis, treatment, and outcome in 8 dogs and 2 cats with global hypoxic-ischemic brain injury (2010-2022).

BACKGROUND: Global hypoxic-ischemic brain injury (GHIBI) results in variable degrees of neurological dysfunction. Limited data exists to guide prognostication on likelihood of functional recovery. HYPOTHESIS: Prolonged duration of hypoxic-ischemic insult and absence of neurological improvement in the first 72 hours are negative prognostic indicators. ANIMALS: Ten clinical cases with GHIBI. METHODS: Retrospective case series describing 8 dogs and 2 cats with GHIBI, including clinical signs, treatment, and outcome. RESULTS: Six dogs and 2 cats experienced cardiopulmonary arrest or anesthetic complication in a veterinary hospital and were promptly resuscitated. Seven showed progressive neurological improvement within 72 hours of the hypoxic-ischemic insult. Four fully recovered and 3 had residual neurological deficits. One dog presented comatose after resuscitation at the primary care practice. Magnetic resonance imaging confirmed diffuse cerebral cortical swelling and severe brainstem compression and the dog was euthanized. Two dogs suffered out-of-hospital cardiopulmonary arrest, secondary to a road traffic accident in 1 and laryngeal obstruction in the other. The first dog was euthanized after MRI that identified diffuse cerebral cortical swelling with severe brainstem compression. In the other dog, spontaneous circulation was recovered after 22 minutes of cardiopulmonary resuscitation. However, the dog remained blind, disorientated, and ambulatory tetraparetic with vestibular ataxia and was euthanized 58 days after presentation. Histopathological examination of the brain confirmed severe diffuse cerebral and cerebellar cortical necrosis. CONCLUSIONS AND CLINICAL IMPORTANCE: Duration of hypoxic-ischemic insult, diffuse brainstem involvement, MRI features, and rate of neurological recovery could provide indications of the likelihood of functional recovery after GHIBI.

Successful resuscitation and neurological monitoring of a dog with out-of-hospital cardiopulmonary arrest due to pentobarbital overdose.

OBJECTIVE: To describe the clinical signs, electroencephalographic (EEG) findings, treatment, and outcome in a dog after successful resuscitation from out-of-hospital cardiopulmonary arrest (OHCA) induced by pentobarbital intoxication. CASE SUMMARY: A 10-year-old, male intact Jack Russell Terrier was referred for management of refractory status epilepticus and presented dead on arrival. After 7 minutes of cardiopulmonary resuscitation, return of spontaneous circulation was achieved, but the dog remained comatose, apneic, and lacked brainstem reflexes on neurological examination 6 hours following resuscitation. Magnetic resonance imaging showed polioencephalomalacia consistent with prolonged epileptiform activity, and EEG was initially concerning for electrocerebral inactivity. Following supportive care that included short-term mechanical ventilation, the dog made a full recovery and was discharged from the hospital alive 7 days postresuscitation. It was later revealed that the dog had been administered an unknown amount of pentobarbital during transportation, which likely contributed to the OHCA, clinical, and EEG findings. NEW INFORMATION PROVIDED: This is the first report to describe the full recovery and hospital discharge of a dog suffering OHCA and the first description of EEG findings in a clinical veterinary patient following cardiopulmonary arrest and successful resuscitation. Factors likely contributing to successful patient outcome and potential benefits and limitations of EEG in monitoring postcardiac arrest patients are discussed.

Evaluation of automated external defibrillator designed for people in dogs.

OBJECTIVE: To determine if human automated external defibrillators (AEDs) could successfully record cardiac electrical activity in dogs, make appropriate recommendations regarding shock delivery, and characterize skin preparation required for a readable ECG based on dog haircoat characteristics. DESIGN: Prospective study of AED use in dogs conducted between January and March 2021. SETTING: University teaching hospital. ANIMALS: Three groups of client-owned dogs were evaluated. Group 1 consisted of 23 healthy dogs with sinus rhythms, group 2 consisted of 9 dogs with documented cardiac arrhythmias, and group 3 consisted of 9 dogs receiving CPR following naturally occurring cardiopulmonary arrest. MATERIALS AND METHODS: Haircoat characteristics and clipping or ECG paste required to obtain a readable ECG were recorded. The time interval from a readable ECG by the investigator until AED shock advisement was measured. Correctness of shock advice was recorded. Analyses were performed using commercial statistical software. P-values <0.05 were considered significant. RESULTS: The attending veterinarian judged the ECG on the AED to be readable in all dogs. Time to shock advisement in all dogs was median 18 (range: 7-180) seconds. Dogs with heavy, long, or double haircoats required clipping in 24 of 27 (89%) cases to obtain a readable ECG. ECG paste on the AED pad was required in 36 of 40 dogs (90%) in order to obtain a readable ECG. The AED advice for delivery of shock was appropriate in 51 of 52 (98%) queries of the machine across all groups. CONCLUSIONS: Human AEDs can successfully record cardiac electrical activity in dogs. AEDs appropriately recommend delivery of a shock most times, contingent on skin preparation. Dogs with double, long, or heavy haircoats should be clipped prior to pad application. ECG paste will aid AED reading in all haircoat types. Further investigation is warranted into AED use in dogs, particularly in general practices.

Association of point-of-care blood variables obtained from dogs and cats during cardiopulmonary resuscitation and following return of spontaneous circulation with patient outcomes.

OBJECTIVE: To investigate the association of point-of-care biochemical variables obtained during CPR or within 24 hours of return of spontaneous circulation (ROSC) with patient outcomes. DESIGN: Retrospective study. SETTING: University teaching hospital. ANIMALS: Ninety-four dogs and 27 cats undergoing CPR according to the Reassessment Campaign on Veterinary Resuscitation guidelines. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Blood gas, acid-base, electrolyte, glucose, and plasma lactate values obtained during CPR or within 24 hours of ROSC were retrospectively evaluated and are described. The blood sample type and collection time with respect to CPR initiation and ROSC were recorded. Measured variables, collection times, and species were included in a multivariable logistic regression model to estimate the odds ratio (OR) and 95% confidence interval of ROSC, sustained ROSC (≥20 min), and survival to hospital discharge. Significance was set at P < 0.05. Seventy-two venous blood samples obtained during CPR and 45 first venous and arterial blood samples obtained after ROSC were included in logistic regression analysis. During CPR, PvO2 (1.09 [1.036-1.148], P = 0.001) and venous standard base excess (SBE) (1.207 [1.094-1.331], P < 0.001) were associated with ROSC. PvO2 (1.075 [1.028-1.124], P = 0.002), SBE (1.171 [1.013-1.353], P = 0.032), and potassium concentration (0.635 [0.426-0.946], P = 0.026) were associated with sustained ROSC. Potassium concentration (0.235 [0.083-0.667], P = 0.007) was associated with survival to hospital discharge. Following ROSC, pH (69.110 [4.393-1087], P = 0.003), potassium concentration (0.222 [0.071-0.700], P = 0.010), and chloride concentration (0.805 [0.694-0.933], P = 0.004) were associated with survival to hospital discharge. CONCLUSIONS: Biochemical variables such as PvO2 , SBE, and potassium concentration during CPR and pH, potassium, and chloride concentration in the postarrest period may help identify dogs and cats with lower odds for ROSC or survival to hospital discharge following CPR.

Reassessment Campaign on Veterinary Resuscitation (RECOVER) Initiative small animal CPR registry report 2016-2021.

OBJECTIVE: To introduce the Reassessment Campaign on Veterinary Resuscitation (RECOVER) CPR registry and report cardiopulmonary arrest (CPA) and CPR event data collected to date. DESIGN: International, multi-institutional veterinary CPR registry data report. SETTING: Veterinary private practice and university teaching hospitals. ANIMALS: Data from 514 dogs and 195 cats undergoing CPR entered in the RECOVER CPR registry between February 2016 and November 2021. INTERVENTIONS: The RECOVER CPR registry is an online medical database created for standardized collection of hospital, animal, arrest, and outcome information on dogs and cats undergoing CPR. Data were collected according to the veterinary Utstein-style guidelines for standardized reporting of in-hospital CPR in dogs and cats. Case records were downloaded, duplicate and incomplete cases were removed, and summary descriptive data were reported. MEASUREMENTS AND MAIN RESULTS: Sixteen hospitals in the United States, Europe, and Australia contributed data on 709 CPR events to the registry. One hundred and forty-two (28%) dogs and 58 (30%) cats attained return of spontaneous circulation (ROSC), 62 (12%) dogs and 25 (13%) cats had ROSC >20 minutes, and 14 (3%) dogs and 4 (2%) cats survived to hospital discharge. The reason for CPR discontinuation was reported as owner choice in 321 cases (63%). The most common suspected causes for CPA were respiratory failure (n = 142, 20%), heart failure (n = 86, 12%), and hemorrhage (n = 76, 11%). CONCLUSION: The RECOVER CPR registry contains the first multicenter data set on small animal CPR. It confirms poor outcomes associated with CPA, emphasizing the need for large-sized studies to gain adequate information on characteristics associated with favorable outcomes.

Cardiopulmonary resuscitation outcomes of dogs and cats at a veterinary teaching hospital before and after publication of the RECOVER guidelines.

OBJECTIVES: To describe and compare cardiopulmonary resuscitation outcomes at a Swiss veterinary teaching hospital before and after publication of the Reassessment Campaign on Veterinary Resuscitation guidelines. MATERIALS AND METHODS: Between 2018 and 2020, hospital staff underwent various types of yearly Reassessment Campaign on Veterinary Resuscitation-based cardiopulmonary resuscitation trainings. Canine and feline cardiopulmonary resuscitation events during that period (post-Reassessment Campaign on Veterinary Resuscitation) and between 2010 and 2012 (pre-Reassessment Campaign on Veterinary Resuscitation) were identified and animal, arrest and outcome variables recorded retrospectively. RESULTS: Eighty-one animals were included in the pre-Reassessment Campaign on Veterinary Resuscitation group and 190 in the post-Reassessment Campaign on Veterinary Resuscitation group. Twenty-three percent in the pre-Reassessment Campaign on Veterinary Resuscitation group and 28% in the post-Reassessment Campaign on Veterinary Resuscitation group achieved return of spontaneous circulation and 1% and 4% survived to hospital discharge, respectively. Patients undergoing anaesthesia [odds ratio 4.26 (1.76 to 10.27)], elective [odds ratio 5.16 (1.06 to 25.02)] or emergent surgery [odds ratio 3.09 (1.20 to 8.00)], or experiencing cardiopulmonary arrest (CPA) due to arrhythmias [odds ratio 4.31 (1.44 to 12.93)] had higher odds of return of spontaneous circulation, while those with unknown cause of CPA [odds ratio 0.25 (0.08 to 0.78)] had lower odds. Undergoing cardiopulmonary resuscitation in the post-Reassessment Campaign on Veterinary Resuscitation period was not statistically significantly associated with return of spontaneous circulation [odds ratio 1.38 (0.68 to 2.79)]. CLINICAL SIGNIFICANCE: Unchanged odds of return of spontaneous circulation observed in this study could suggest that once-yearly cardiopulmonary resuscitation training is insufficient, effects of animal and tertiary referral hospital variables confounded results, guideline benefit is limited, or that compliance during clinical cardiopulmonary resuscitation efforts is too poor for guideline recommendations to have a positive impact.

Brain magnetic resonance imaging and histopathology findings in a dog with global brain ischaemia following cardiopulmonary arrest.

BACKGROUND: Global brain ischaemia following cardiopulmonary arrest is uncommonly reported in veterinary medicine yet neurologic injury after arrest is a known morbidity. CASE REPORT: An 18-week-old male entire Cavalier King Charles Spaniel-Poodle was referred following 3 days of neurologic abnormalities after cardiopulmonary arrest. After resuscitation, the animal had decerebrate rigidity, a stuporous mentation and intermittent episodes of vocalisation and apnoea. A brain magnetic resonance imaging (MRI) was undertaken 4 days after cardiopulmonary arrest, with standard sequences (T1-weighted, T2-weighted and fluid-attenuated inversion recovery) as well as diffusion-weighted imaging to better discern ischaemic injury and cytotoxic oedema for prognostic reasons. MRI findings were consistent with global brain ischaemia affecting the hippocampus, cerebellum and substantia nigra, the latter two not previously identified in canine cases of global brain ischaemia. The patient was euthanased on day eight post-cardiopulmonary arrest due to a lack of neurological improvement and developing sepsis as a complication. Ante-mortem identification of affected areas of the brain was confirmed on histological examination, with evidence of ischaemic injury seen in the cerebrum, hippocampus, cerebellum, basal nuclei and thalamus. CONCLUSION: This report describes ante-mortem MRI and postmortem findings in a dog with global brain ischaemia following cardiopulmonary arrest. A multimodal approach to neuroprognostication in patients recovering from cardiopulmonary arrest is recommended.

Mitral valvuloplasty with left atrial appendage closure and pacemaker implantation in a dog with severe myxomatous mitral valve degeneration: a case report.

BACKGROUND: Mitral valvuloplasty (MVP) has been widely recognized as a treatment option for myxomatous mitral valve disease (MMVD). However, postoperative complications such as thromboembolism, arrhythmia, and pancreatitis in some cases have resulted in death. We treated a dog with severe MMVD complicated by impaired sinus function with MVP and pacemaker implantation. Also, due to an intrinsic procoagulant state and severe arrhythmia after the MVP, left atrial appendage (LAA) closure was performed to reduce the postoperative risk of thrombosis. CASE PRESENTATION: An 11-year-old castrated 7.5-kg male Miniature Schnauzer with a history of congestive heart failure was brought to Shiraishi Animal Hospital for MMVD surgical treatment. Echocardiography revealed an enlarged left atrium and ventricle secondary to MMVD. Sinus arrest with 2 to 3-second periods of asystole was identified by electrocardiogram. Mitral valvuloplasty was performed with cardiopulmonary bypass to treat the MMVD. After coronary reperfusion, there was no spontaneous electrical activity. Cardiac arrest continued. Based on this surgical outcome, a permanent pacemaker was implanted. In addition, LAA closure with an AtriClip was performed to prevent intra-atrial thrombus formation. Cardiac remodeling and congestion were ameliorated after surgery. Sinus rhythm was restored 5 days postoperatively; however, the patient continued pacemaker dependent. All cardiac drugs were discontinued 3 months after surgery. The owner reported no postoperative complications (i.e., thrombosis), and the patient was brought for a check-up 4 months after the operation in good health. CONCLUSIONS: For surgical MMVD cases complicated with impaired sinus function, the chances of spontaneous sinus rhythm are low, requiring pacemaker implantation. LAA closure may be considered to protect against decreased atrial function after mitral valvuloplasty and prevent intra-atrial thrombus formation.