RECOVER evidence and knowledge gap analysis on veterinary CPR. Part 5: Monitoring

Serial paired arterial and jugular venous point-of-care values in dogs undergoing manual basic life support

OBJECTIVE

To evaluate differences in point-of-care (POC) variables obtained from arterial and jugular venous blood in dogs undergoing manual basic life support (BLS) and report changes over time.

DESIGN

Experimental study.

SETTING

Small animal research facility.

ANIMALS

Twenty-four purpose-bred research dogs.

INTERVENTIONS

Dogs were anesthetized, and arterial catheters were placed before euthanasia. One minute after cardiopulmonary arrest, BLS consisting of manual chest compressions and ventilation delivered via endotracheal intubation, face mask, mouth-to-nose, or no ventilation was initiated. Paired arterial and jugular venous blood samples were obtained for POC testing before euthanasia (T0), at 3 minutes (T3), and at 6 minutes (T6) into BLS.

MEASUREMENTS AND MAIN RESULTS

The association of POC variables with arterial or venous sample type while controlling for type of ventilation and sampling timepoint was determined using a generalized linear mixed model. Variables obtained from arterial and venous blood samples were compared over time using repeated measures ANOVA or Friedman test. Pao2, anion gap, potassium, chloride, glucose concentration, and PCV were significantly higher in arterial blood samples compared with venous samples (P < 0.03). By T6, arterial glucose concentration, arterial and venous base excess, venous pH, and plasma lactate, potassium, creatinine, bicarbonate, and sodium concentrations were significantly increased, and arterial and venous Po2, ionized calcium concentration, PCV, and total plasma protein concentration were significantly decreased from T0 (P < 0.05).

CONCLUSIONS

Although statistically significant, arteriovenous differences and changes in POC blood variables during BLS were small and not clinically relevant over time. Given the challenges of arterial blood sampling, it may be reasonable to pursue venous blood sampling during CPR. Further studies in dogs undergoing BLS and advanced life support are needed to better understand the potential clinical role of POC testing during CPR.

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.

Self-Reported Clinical Practice of Small Animal Cardiopulmonary Resuscitation and Compliance With RECOVER Guidelines Among Veterinarians in Eight Western European Regions

Introduction

The objective of this study was to assess whether small animal veterinarians across Western Europe are compliant with the 2012 cardiopulmonary resuscitation (CPR) guidelines by the Reassessment Campaign on Veterinary Resuscitation (RECOVER).

Methods

A previously published online questionnaire from Switzerland was adapted and translated into 7 languages, corresponding to national languages in Austria, France, Germany, Ireland, Italy, Liechtenstein, Netherlands, Portugal, Spain, and the United Kingdom. The survey was distributed via respective national veterinary organizations and social media outlets. A subset of questions was analyzed to evaluate respondent demographics, RECOVER guideline awareness, and to allocate composite compliance scores for CPR preparedness, basic life support (BLS) and advanced life support (ALS). Percentages of group total (95% confidence interval) were calculated. Multivariable logistic regression was used to evaluate the effects of region of practice, gender, age, specialty training, and guideline awareness on compliance. Odds ratios (95% confidence interval) were generated and significance set at P &lt; 0.05.

Results

Nine-hundred and thirty respondents were included in analysis. Awareness of and compliance with RECOVER guidelines varied widely across regions. Compliance with all assessed RECOVER guideline recommendations was highest in Germany/Austria [14% (7- 27%)] and lowest in France and Portugal [0% (0–3%)]. CPR preparedness compliance was higher in participants aware of RECOVER guidelines [OR 10.1 (5.2-19.5)], those practicing in Germany/Austria [OR 4.1 (1.9–8.8)] or UK/Ireland [OR 2.2 (1.3–3.7)], and lower in those practicing in Portugal [OR 0.2 (0.1–0.9)]. Specialty training [OR 1.8 (1.1–2.9)], guideline awareness [OR 5.2 (3.2–8.6)], and practice in Germany/Austria [OR 3.1 (1.5–6.5)], UK/Ireland [OR 2.6 (1.7–4.1)], or the Netherlands [OR 5.3 (2.0–14.2)] were associated with increased BLS compliance. ALS compliance was higher in participants with guideline awareness [OR 7.0 (2.9–17.0)], specialty training [OR 6.8 (3.8–12.1)], those practicing in Germany/Austria [OR 3.5 (1.3–9.6)], UK/Ireland [OR 4.0 (1.9–8.3)], or Spain [OR 3.2 (1.2–8.3)] and in younger survey participants [OR 0.9 (0.9–1.0)].

Conclusions

Awareness and compliance with RECOVER guidelines varied widely among countries surveyed, however overall compliance scores in all countries were considered low. Further research may highlight factors surrounding poor guideline awareness and compliance so targeted efforts can be made to improve veterinary CPR in Europe.

[Pulmonary function testing in the cat - an overview]

This article provides an overview of currently available pulmonary function tests in cats, divided into invasive and non-invasive methods. Invasive techniques comprise arterial blood gas analysis and measurement of pulmonary mechanics. Non-invasive techniques include pulse oximetry and capnography, as well as methods not yet integrated into everyday practice such as tidal breathing airflow-volume loops, whole-body barometric plethysmography and thorax compression. In this article, the background, execution, interpretation, and limitations of each test are discussed. Proper performance and assessment of pulmonary function measurements may aid in understanding the pathophysiology of feline respiratory disease and in increasing objectivity when assessing the existing disease and treatment efficacy.

Feline cardiopulmonary resuscitation: Getting the most out of all nine lives

PRACTICAL RELEVANCE

Cardiopulmonary arrest (CPA) can occur in any veterinary or animal care setting and is a particular risk in scenarios involving ill, injured or anesthetized patients. Education of all staff on the prevention and recognition of CPA, as well as the performance of cardiopulmonary resuscitation (CPR), is vital to influencing outcome.

EVIDENCE BASE

While there is a plethora of information regarding CPA and CPR in human medicine, there are comparably few studies in the veterinary literature. Many of the current veterinary guidelines are extrapolated from human medicine or studies based on animal models. Ongoing work is needed to tailor guidelines and recommendations to our domestic feline (and canine) patients in a clinical setting.

AIM

The aim of this article, which is intended for veterinarians in all areas of small animal practice, is to provide an evidence-based review of CPA and CPR in feline patients. The authors have drawn heavily on detailed recommendations published by the Reassessment Campaign on Veterinary Resuscitation (RECOVER) initiative - one of the few resources specific to the veterinary clinical setting - as well as reviewing the available peer-reviewed literature studies, in constructing this article. Among the topics discussed are recognizing and preventing CPA, staff training and clinic preparedness, basic life support and advanced life support interventions, and appropriate post-cardiac arrest care.

Evaluation of end-tidal carbon dioxide as a predictor of return of spontaneous circulation in dogs and cats undergoing cardiopulmonary resuscitation

OBJECTIVE

To determine whether the partial pressure of end-tidal carbon dioxide (PetCO₂ ) could predict return of spontaneous circulation (ROSC) in patients with cardiopulmonary arrest (CPA) undergoing CPR.

DESIGN

Prospective observational study.

SETTING

Two private specialty referral hospitals.

ANIMALS

Thirty-five client-owned dogs and cats in CPA in which CPR was performed and pertinent data recorded on a purpose-made form.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

PetCO₂ was recorded at 1-minute intervals during CPR. Hospital, animal, arrest, and outcome variables were also reported in the Utstein style where possible. Twelve animals (7 dogs and 5 cats) achieved ROSC; 4 of these (2 dogs and 2 cats) had sustained ROSC, of which 1 dog was discharged alive. Patients that achieved ROSC had significantly higher initial PetCO₂ (P = 0.0083), peak PetCO₂ (P < 0.0001), average PetCO₂ (P < 0.0001), and ΔPetCO₂ (difference between last and first recorded PetCO₂ ; P = 0.0004) than patients not resuscitated. The PetCO₂ accurately discriminated between ROSC and failure to achieve ROSC at minutes 3, 4, 5, 6, 7, and 8 of CPR with area under the receiver operating characteristic curve of 0.926, 0.967, 0.938, 0.933, 0.956, and 1.00, respectively. The optimal cutoff PetCO₂ was 18 mm Hg (2.4 kPa), with a sensitivity of ≥80% and a specificity of ≥95% at minutes 3, 4, 5, 6, and 8, correctly classifying 91-100% of cases.

CONCLUSIONS

The results of this small study support previous recommendations to monitor PetCO₂ during CPR and suggest that PetCO₂ during CPR may be useful for determining the probability of ROSC. Absolute values and trends of PetCO₂ may assist clinicians and owners in making decisions for pets with CPA.

A systematic review of clinical audit in companion animal veterinary medicine

Background

Clinical audit is a quality improvement process with the goal of continuously improving quality of patient care as assessed by explicit criteria. In human medicine clinical audit has become an integral and required component of the standard of care. In contrast, in veterinary medicine there appear to have been a limited number of clinical audits published, indicating that while clinical audit is recognised, its adoption in veterinary medicine is still in its infancy. A systematic review was designed to report and evaluate the veterinary literature on clinical audit in companion animal species (dog, cat, horse). A systematic search of English and French articles using Proquest Dissertations and Theses database (February 6, 2014), CAB Abstracts (March 21, 2014 and April 4, 2014), Scopus (March 21, 2014), Web of Science Citation index (March 21, 2014) and OVID Medline (March 21, 2014) was performed. Included articles were those either discussing clinical audit (such as review articles and editorials) or reporting parts of, or complete, audit cycles.

Results

The majority of articles describing clinical audit were reviews. From 89 articles identified, twenty-one articles were included and available for review. Twelve articles were reviews of clinical audit in veterinary medicine, five articles included at least one veterinary clinical audit, one thesis was identified, one report was of a veterinary clinical audit website and two articles reported incomplete clinical audits. There was no indication of an increase in the number of published clinical audits since the first report in 1998. However, there was evidence of article misclassification, with studies fulfilling the criteria of clinical audit not appropriately recognised. Quality of study design and reporting of findings varied considerably, with information missing on key components, including duration of study, changes in practice implemented between audits, development of explicit criteria and appropriate statistical analyses.

Conclusions

Available evidence suggests the application and reporting of clinical audit in veterinary medicine is sporadic despite the potential to improve patient care, though the true incidence of clinical audit reporting is likely to be underestimated due to incorrect indexing. Reporting standards of clinical audits are highly variable, limiting evaluation, application and repeatability of published work.

Electronic supplementary material

The online version of this article (doi:10.1186/s12917-016-0661-4) contains supplementary material, which is available to authorized users.

Changes in adherence to cardiopulmonary resuscitation guidelines in a single referral center from January 2009 to June 2013 and assessment of factors contributing to the observed changes

BACKGROUND

This retrospective study reviewed compliance to cardiopulmonary resuscitation (CPR) teaching at a small animal referral center from January 2009 to June 2013. CPR training commenced in October 2009. This was a lecture format by European specialists in veterinary anesthesia and analgesia. Teaching was originally based on published guidelines. Changes made to the content of the lectures after publication of the Reassessment Campaign on Veterinary Resuscitation (RECOVER) guidelines in 2012 are discussed.

KEY FINDINGS

Data regarding basic life support and monitoring equipment were collected from all cases requiring CPR. A Mann-Kendall test for trend showed a significant increased use of both capnography (P = 0.017) and suction to aid tracheal intubation (P = 0.017) over the period of study. There was a significant increase in capnography use in 2011 (P = 0.046), 2012 (P = 0.002), and 2013 (P = 0.002) compared to 2009 (1/15).

SIGNIFICANCE

The sequential increase in capnography use without any change to the number or availability of capnography units provides evidence that CPR teaching has altered clinical practice. The publication of the RECOVER guidelines provided an evidence base upon which to refine and improve teaching of CPR.

Physiologic Measures of Animal Stress during Transitional States of Consciousness

Determination of the humaneness of methods used to produce unconsciousness in animals, whether for anesthesia, euthanasia, humane slaughter, or depopulation, relies on our ability to assess stress, pain, and consciousness within the contexts of method and application. Determining the subjective experience of animals during transitional states of consciousness, however, can be quite difficult; further, loss of consciousness with different agents or methods may occur at substantially different rates. Stress and distress may manifest behaviorally (e.g., overt escape behaviors, approach-avoidance preferences [aversion]) or physiologically (e.g., movement, vocalization, changes in electroencephalographic activity, heart rate, sympathetic nervous system [SNS] activity, hypothalamic-pituitary axis [HPA] activity), such that a one-size-fits-all approach cannot be easily applied to evaluate methods or determine specific species applications. The purpose of this review is to discuss methods of evaluating stress in animals using physiologic methods, with emphasis on the transition between the conscious and unconscious states.

Pulse oximetry and capnometry

Respiratory dysfunction is common in veterinary patients and various techniques have been developed to rapidly and accurately monitor pulmonary gas exchange. Pulse oximetry and capnometry are tools that allow for continuous evaluation of pulmonary function. Methodology, indications, and limitations of pulse oximetry and capnometry are discussed in this article. Both techniques are useful for monitoring critically ill or anesthetized patients; however, limitations to their use exist which underscore the need for intermittent arterial blood gas analysis.

Acid base, electrolyte, glucose, and lactate values during cardiopulmonary resuscitation in dogs and cats

OBJECTIVE

To report acid base, electrolyte, glucose, and lactate values collected during or immediately after cardiopulmonary resuscitation (CPR) in dogs and cats.

DESIGN

Retrospective study.

SETTING

University Teaching Hospital.

ANIMALS

Thirty-two dogs and 10 cats.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Blood gas, electrolyte, glucose, and lactate values measured during CPR or within 5 minutes of return of spontaneous circulation (ROSC) were retrospectively evaluated. The time of blood collection with respect to the occurrence of cardiopulmonary arrest (CPA), the initiation of CPR or ROSC was noted. Forty-two venous blood samples were analyzed, 24 collected during CPR and 18 samples were collected within 5 minutes of ROSC. Metabolic acidosis and hyperlactatemia were evident in all samples in the study while an increased PvCO2 occurred in 88% of samples collected during CPR and in 61% of samples collected following ROSC. Hyperkalemia occurred in 65% of all cases, decreased ionized calcium was evident in 18%, hypoglycemia was evident in 21% while hyperglycemia was evident in 62%. There was no significant difference in any parameter evaluated between dogs and cats during CPR. There was no significant difference of any variable measured during the first 15 minutes of CPA versus those measured more than 15 minutes following CPA. When the values measured during the first 5 minutes of ROSC were compared to those measured during CPR, the pH and PvO2 were significantly lower in the CPR group.

CONCLUSIONS

Biochemical abnormalities including metabolic acidosis, hyperkalemia, ionized hypocalcemia, hypoglycemia, and hyperglycemia can be identified during CPR and immediately following ROSC. The therapeutic and prognostic relevance of these changes are yet to be defined and may prove to be useful to guide patient management in the future.

Updates in small animal cardiopulmonary resuscitation

For dogs and cats that experience cardiopulmonary arrest, rates of survival to discharge are 6% to 7%, as compared with survival rates of 20% for people. The introduction of standardized cardiopulmonary resuscitation guidelines and training in human medicine has led to substantial improvements in outcome. The Reassessment Campaign on Veterinary Resuscitation initiative recently completed an exhaustive literature review and generated a set of evidence-based, consensus cardiopulmonary resuscitation guidelines in 5 domains: preparedness and prevention, basic life support, advanced life support, monitoring, and postcardiac arrest care. This article reviews some of the most important of these new guidelines.