As we're amidst the dog days of summer, we continue to offer the most current, intriguing veterinary news and information.

 that measures pet temperatures under the foreleg or hindleg and swiftly sends the results to practice management software.

recently acquired its third acquisition of the year

, Central Animal Clinic, expanding its new veterinary clinics to 6.

 to find out what's causing this Frenchie with intervertebral disc disease skin lesions. 

 as the new CEO, bringing 15 years of scientific and commercial expertise within the animal health industry to the team.

From a smart cat water bowl to online scheduling platforms, here's a 

rundown of the latest veterinary products

Stay tuned on social media and dvm360.com for more veterinary news.

Articles

News wrap up: This week's veterinary headlines, plus first non-invasive pet thermometer 

Veterinary practice discovery and booking platform

VetVet is a website that helps clients search for and book appointments with veterinarians who best meet their pet’s needs. Because each veterinarian has unique training and experience, this platform hones in on the complementary professional for new patients. The digital platform’s booking and onboarding capabilities help to save time for both clients and office staff members. By digitizing booking and helping to fill empty appointment slots, VetVet improves practice efficiency and helps drive increases in revenue.

Purina Pro Plan Veterinary Supplements Calming Care

Purina Pro Plan Veterinary Supplements Calming Care for cats contain 

 (BL999), a probiotic strain shown to help promote calm behavior in felines. Calming Care aids cats in managing changes in routine and location while encouraging positive behaviors (eg, playing, seeking out social contact). Because diet-related changes in gut microbiota can influence the brain via the gut-brain axis and therefore, may influence anxious behaviors, BL999 targets the gut-brain axis to alter anxious behavior. Calming Care is packaged in boxes of 45 sachets. It should be supplemented daily for at least 6 weeks to evaluate efficacy.

Felaqua Connect is the smart cat water bowl that provides insights into drinking behavior by connecting with your cat's microchip, highlighting changes which may otherwise be missed. Its wide, shallow bowl presents water in a way that is more visible and appealing to your cat. Felaqua Connect delivers clean, fresh water and automatically refills from the reservoir—no recirculating water or filters. Felaqua Connect is battery operated, cable free, and dishwasher safe. Pair Felaqua Connect with the Sure Petcare App which indicates how often, when, and how much your cat drinks and receive notifications when the water needs to be changed.

Launched by Walmart, this veterinarian-formulated pet food line for dogs and cats complements the 9-year-old Pure Balance brand. Deemed “super-premium,” the 9 new diets are made with either chicken, salmon, or turkey as the first ingredient. This formula contains natural ingredients, plus added vitamins, minerals, and other nutrients, and is free of artificial colors, flavors, or preservatives. The food line includes Pro+: Puppy, Senior Dog, Weight Management for Dogs, Weight Management for Cats, Small Breed for Dogs, Large Breed for Dogs, Kitten (wet and dry), Senior Cat, Sensitive Skin & Stomach for Cats.

This clinically tested smart axillary thermometer is the first-ever to measure feline and canine temperature under the foreleg or hindleg while immediately sending results to practice manager software. In partnership with Vetspire, a cloud-based veterinary practice management system, Mella Pro uses Bluetooth connectivity to provide the first end-to-end integrated vital signs measurement on both the veterinary and human market. It uses various temperature sensors, millions of patient records, and machine learning to calculate an accurate reading. Mella Pro displays the result within 10 to 15 seconds and can be used both at home and the clinic.

Vetster connects pet owners to thousands of licensed veterinarians prepared to offer the best online services through video chat appointments 24/7. This unique platform allows users to search for available veterinarians in their area and find a match within seconds—no downloads required. From initial concern to diagnosis to product delivery, receive prescriptions delivered to your door in 2 days or less. Veterinary professionals interested in working for the platform can set their own hours and are quickly compensated for all completed appointments through the convenient payout processing. Vetster can be accessed on your computer, tablet, or mobile device.

This bivalent canine flu vaccine by Zoetis effectively protects canines against both highly contagious H3N2 and H3N8 strains of canine influenza virus (CIV). This vaccine is approved for use in healthy dogs age 8 weeks and older. A study examining efficacy revealed that the vaccine not only protected dogs from disease, but also appeared to assist in decreasing the number of days for shedding the CIV H3N2 virus. This convenient vaccine protects dogs from both known CIV strains, thus, helping to protect canines overall in the community by increasing herd immunity. Dogs should initially receive 2 doses administered 3 weeks apart. The need for an annual booster vaccination has not yet been established; consultation with a veterinarian is recommended. Available in 25 x 1-dose packages.

If your area is in the midst of a CIV outbreak, go 

Vetstoria helps practices save time, enhance service, and grow by providing pet owners the ability to book appointments conveniently from the clinic’s website. These appointments are then synced straight into the practice management system calendar in real-time. Including a user-friendly dashboard that enables you to set your preferences, this platform helps to control availability and replicate your existing booking workflow. You can embed Vetstoria on your website or share booking links in email campaigns, text messages, social profiles, and much more. Plus, accept payments at the time of booking and easily send automated appointment reminders. Some Vetstoria features include:

Real-time sync with your existing calendar

Here's our regular rundown of new and notable veterinary products.

dvm360 product report: Smart cat water bowl, plus a noninvasive pet thermometer and more   

CityVet—a leading network of 20 veterinary-owned practices providing exceptional pet care based in Dallas, Texas—recently announced its acquisition of Central Animal Clinic, located in Cedar Hill, Texas and known for its specialization in small animal medicine for over 30 years.

According to a company release, this transaction serves as CityVet’s third acquisition within the year and broadens its new veterinary clinics to 6.

“We are excited to join the CityVet network. They are paving the way for our associate veterinarian to have ownership in the clinic and to grow as a leader,” says Chris Rose, DVM, founder of Central Animal Clinic, in the release.

“CityVet believes in putting people at the center of everything they do, and our team looks forward to this next chapter. Their facilities are state of the art, and I can’t wait to see the remodel of our clinic,” he adds.

Over the last 20 years, CityVet’s expansion has been centered around developing a de novo model and offering a unique opportunity for lead veterinarians to have ownership in their hospital. Additionally, Central Animal Clinic will be the third non-branded clinic in the company’s portfolio.

“Dr Rose and his team have a well-established clinic in Cedar Hill with a strong reputation as a trusted veterinary partner. Their clients and staff will benefit from our scale and the value-added services we will provide in close partnership with Dr. Rose,” says David Boguslawski, CityVet CEO, in the release.

“We have a plan to make significant building updates and are excited to help grow the legacy Dr. Rose and his team established in Cedar Hill,” he continued.

The terms of the transaction were not disclosed. This acquisition is effective as of July 15, 2021. For more information about CityVet and its mission, go 

This transaction expands the company’s new clinics to 6 and marks its third acquisition within the year.

CityVet acquires Central Animal Clinic

Fluid therapy is a dynamic topic in the medical field. In the 19th century (and for many centuries prior), medical doctors thought bloodletting was a reasonable treatment for a variety of conditions. Fast-forward to the 1950s and beyond, when the mainstay of treatment became aggressive intravenous (IV) fluid boluses. Until recently, fluid boluses were routinely given to most patients in an emergency setting. However, recent studies in the human and veterinary fields have demonstrated that aggressive fluid therapy is not always beneficial and may often be detrimental to our patients. This article will review the fundamentals of fluid therapy, how to approach critical patients with regard to fluid therapy, and the consequential role of the endothelial glycocalyx.

Calculating maintenance fluid requirements

Defining maintenance rate is often a point of contention. Some sources state the general rule of thumb for maintenance requirements should be 40 to 60 mL/kg/day. The problem with this estimation is that it is less accurate in very small and very large patients. Maintenance requirements are based on body surface area, which is a logarithmic measurement, not linear.

A more accurate measurement is based on metabolic rate; it is estimated that 1 kcal = 1 mL H

O. The simplest method to calculate basal metabolic rate or basal energy requirement (BER) is: [30 × BW(kg)] + 70. This has been shown to be accurate for patients over 2 kg and under 100 kg. In patients outside this range, a more accurate calculation is [BW (kg)^0.75] × 70. Estimating their maintenance based on BER alone will be slightly under their maintenance needs because BER assumes no activity. Consequently, using a multiplier between 1.2 and 2 may better approximate the true metabolic expenditure of the patient, and therefore their maintenance energy requirements.

However, given that fluid overload is more detrimental to a patient than being slightly dehydrated,

the author’s preference is simply to use BER as the maintenance rate, especially because more fluid will be added to the total rate in order to account for replacing the estimated fluid deficit as well as ongoing losses. Any formula you come across for estimating maintenance fluid rates is just that—an estimate. This is why frequent monitoring of patients receiving IV fluids is so crucial.

Although IV fluid therapy is the most common route for hospitalized patients, there are multiple routes by which fluid therapy can be administered. Choosing which route depends on the patient, their specific needs, and their disease state.

Per os fluids are often forgotten and underrated. As long as there are no contraindications, such as vomiting or regurgitation, free access to water should always be allowed. In addition, fluids can be administered via a nasogastric tube if the patient is having one placed for other purposes.

 A classic example in which oral fluids can be very helpful in a critical setting would be a puppy with parvovirus enteritis (typically these patients are on CliniCare or another type of feeding with a high water content, but additional water boluses of 20-30 mL of lukewarm water can be given q2-4h.

Not only do enteral fluids stimulate the intestinal tract, but this is also the safest route of fluid administration in terms of avoiding fluid overload. In a patient with hypoalbuminemia, a heart murmur, or other comorbidities that may exacerbate hypervolemia, oral fluid administration should be considered. Oral fluids are contraindicated in any patient that has recently been vomiting or regurgitating.

Administering fluids subcutaneously is reasonable for rehydration; however, this is not an appropriate route of administration for patients exhibiting any signs of shock. Only isotonic solutions such as lactated Ringer’s solution (LRS) or Normosol-R (NSR) can be used, and they should be free of additives. The recommended dose is typically 30 to 40 mL/kg but can be higher in younger animals and exotic species. Subcutaneous fluids are contraindicated for any hypovolemic patient.

In any patient that is exhibiting signs of shock, not eating or drinking normally, anesthetized, or showing significant acid-base or electrolyte abnormalities, IV administration is the route of choice. IV access allows rapid volume resuscitation, correction of electrolyte abnormalities, and restoration of euglycemia in hypoglycemic patients. However, IV fluids are contraindicated in patients with congestive heart failure or any noncardiogenic causes of pulmonary edema. IV fluids should be used cautiously in patients with cavitary effusions, hypoalbuminemia, oliguric or anuric renal failure, heart murmur or gallop rhythm, or any other comorbidities that may contribute to fluid overload.

In patients for which IV access cannot readily be obtained (ie, very small patients or some exotic species) and that are also too ill for subcutaneous fluid therapy, intraosseous fluids should be considered. After volume resuscitation using an intraosseous catheter, it is often possible to place an IV catheter, because improved perfusion will expand peripheral vessels.

Crystalloids are the mainstay of fluid therapy. Crystalloids consist of salt in water. Balanced crystalloid solutions also contain electrolytes and a buffer. Crystalloids rapidly redistribute out of the vascular space and into the interstitial space. It is estimated that 75% to 80% of the volume administered will move out of the vascular space within 30 to 60 minutes after administration. Larger volumes of crystalloids are required to have the same hemodynamic effect on a hypovolemic patient as a smaller volume of hypertonic saline (HSS) or a colloid solution. There are many crystalloid options available, but this article will focus on normal saline, balanced isotonic solutions, and HSS.

Normal saline (0.9% NaCl) used to be the mainstay of crystalloid fluid therapy in human medicine. However, studies have shown that normal saline may result in hypernatremia and hyperchloremia, as well as metabolic acidosis. It is important to note that normal saline is not a physiologic solution; it contains far more sodium and chloride than plasma and is acidifying by nature. Studies have also shown that hyperchloremia can lead to impaired renal function and an increased need for renal replacement therapy.

In veterinary medicine, there are several circumstances in which normal saline can be useful. The first is in hypercalcemic patients, because it promotes calciuresis (sodium competes with calcium for tubular resorption). The second condition is in patients with hypochloremic metabolic alkalosis (which is rare but most commonly associated with an upper gastrointestinal obstruction). Furthermore, normal saline can be used to slowly correct severely hypernatremic patients with either a chronic condition or suspected chronic hypernatremia (correction of sodium abnormalities is complex and the intricacies of such are beyond the scope of this article). Normal saline should not be considered the first-choice crystalloid for IV fluid therapy, and it is the author’s belief that it should not be used outside of the 3 circumstances listed above.

Balanced crystalloid solutions are the most physiologic in nature, meaning their composition is most similar to that of plasma, in terms of content and tonicity (290-310 mOsm/L). They contain electrolytes as well as a buffer (lactate, acetate, or gluconate). The most commonly used isotonic crystalloids are NSR, LRS, and Plasma-Lyte (P-lyte). NSR and P-lyte have a sodium content most similar to that of plasma (both are 140 mEq/L), whereas LRS is slightly hypotonic (130 mEq/L with a tonicity of 273 mOsm/L).

LRS is contraindicated in patients with severe liver diseasebecause hepatic function is necessary to convert lactate to bicarbonate. If liver function is impaired, the use of LRS may result in lactic acidosis.

HSS differs from other crystalloids in that it is a good plasma expander. HSS typically comes in a solution of 5% to 7.5% sodium chloride. Hypertonicity causes water to shift from the interstitial and intracellular spaces into the intravascular space, which increases plasma volume. The volume of HSS required to produce specific hemodynamic effects is significantly lower than the volume of crystalloid required to produce the same effects, so HSS is ideal for low-volume fluid resuscitation.

HSS should only be given to patients with normal interstitial and intracellular hydration. For example, HSS is useful for patients with acute hemorrhage or hypovolemic shock secondary to trauma; however, it would be a poor choice in a markedly dehydrated cat with renal failure. The recommended dosing is 3 to 5 mL/kg in dogs and 2 to 4 mL/kg in cats, usually given over 10 to 20 minutes. It is important to keep in mind that additional crystalloids should be given after the administration of HSS to avoid subsequent hypernatremia and interstitial dehydration.

HSS has also been used in patients with traumatic brain injury to reduce intracranial pressure. There have also been studies showing the beneficial effects of HSS on microvascular perfusion and oxygen delivery for patients in hemorrhagic shock. The literature is mixed in terms of the effect of HSS on coagulation; one study published in 2015 showed impaired platelet function and whole blood coagulation following HSS administration,

whereas a study published in 2020 showed no effect on coagulation parameters.

A single bolus given to stabilize an actively hemorrhaging patient, prior to the administration of blood products, is unlikely to have significant effects on coagulation, and should be considered in such patients for low-volume resuscitation.

Colloids contain high molecular weight particles, which cannot cross an intact vascular barrier, and thereby provide significant oncotic support and volume expansion. Therefore, this should reduce the development of interstitial tissue edema, because the fluid remains in the intravascular space. Colloids can be further classified into natural or synthetic colloids.

Hydroxyethyl starches (HES) are the most commonly used synthetic colloid in veterinary medicine. Dextrans and gelatins are the other 2 classes, but they are used less frequently. Hetastarch is the most commonly used HES in veterinary medicine. The benefits of using a synthetic colloid such as hetastarch include maintaining colloid osmotic pressure, low volume resuscitation, rapid intravascular expansion, and a volume of distribution that not only stays within the intravascular space but lasts much longer than it would with crystalloids (up to 6 hours). However, despite these advantages, there is no clinical evidence to support the use of synthetic colloids to reduce morbidity and mortality. In fact, most studies report increased mortality with the use of synthetic colloids, and the most significant adverse effects (AEs) include acute kidney injury and coagulopathies. Other less common but potentially severe AEs include allergic reactions, hepatopathy, pruritus, and reticuloendothelial dysfunction.

 In human medicine, synthetic colloids have fallen out of favor for the treatment of septic shock, as there have been multiple studies showing increased mortality with their use. 

Synthetic colloids can still be considered but must be used with caution and should be avoided in any animal with impaired renal function, coagulopathy, hypervolemia, or heart murmur. The most recent Surviving Sepsis Campaign

recommendations in human medicine advise against the use of synthetic colloids in patients with sepsis or septic shock; it is no longer common practice for veterinarians to use synthetic colloids in such patients. If used, the recommended dose range should not exceed 20 mL/kg/d to minimize or prevent any AEs. This can be given either as a continuous rate infusion or in incremental boluses of 5 mL/kg. In cats, the dose should not exceed 10 mL/kg/d and boluses can be given in increments of 2.5-3 mL/kg/d. Frequent monitoring of patients receiving synthetic colloids is imperative.

In human medicine, 4% albumin is a mainstay of therapy in critically ill patients for a multitude of reasons beyond its colloidal benefit: it helps to maintain and restore the integrity of the endothelial glycocalyx, has anticoagulant properties, protects against oxidative damage, and plays a role in serum drug and hormone binding. Unfortunately, a readily available, species-specific albumin is difficult to obtain in veterinary medicine. Lyophilized canine-specific albumin is sporadically available, and in a small study of 7 dogs with septic peritonitis

 it showed improved outcomes. Given the lack of availability of canine-specific products, human serum albumin (HSA) has been used in veterinary species as well. However, some reports have shown severe and even fatal type III hypersensitivity reactions in dogs treated with HSA. Therefore, the use of HSA is controversial and not widely accepted at this time.

Blood component therapy such as fresh frozen plasma (FFP) can also be considered for colloidal support. Although FFP is typically used for patients with coagulopathies or acute hemorrhage, it also provides other components such as immunoglobulins and albumin, among other plasma components. Although FFP does contain albumin, it takes a significant volume of FFP to increase the concentration of albumin; it is estimated that 45 mL/kg will increase the albumin concentration by 1 mg/dL, and the normal dose for a coagulopathic patient is 10 to 20 mL/kg. Not only is this often cost prohibitive, but administering this volume increases the risk of transfusion-associated AEs. These include transfusion-associated circulatory overload (TACO), transfusion-related acute lung injury (TRALI), and febrile nonhemolytic transfusion reactions.

Part 2: Making a fluid therapy plan and monitoring patients on fluids

Fluids are drugs, and we should put just as much thought into fluid therapy for every patient as we do into administering any other medication. There are 4 main questions to ask yourself when formulating a fluid plan:

Treatment of hypovolemia is addressed in more detail in the next section. Once a patient is volume resuscitated, you can consider the latter 3 questions. If you have given fluid boluses, a repeat physical examination and blood work are helpful to reassess hydration status. For example, if the patient arrived with a packed cell volume/plasma total solids (PCV/TS) value of 65/9.0, then rechecking this parameter will help you know how much progress has been made in correcting the dehydration.

Many parameters can be used to determine the degree of dehydration (see 

 below). The volume to be replaced can be calculated as [weight in kilograms × % dehydration] × 1000 = volume in liters to be replaced. Dehydration should be corrected over the first 12 to 24 hours; however, this should be extended to 36 to 48 hours in patients more susceptible to fluid overload (especially cats). Always keep in mind that if a problem happens slowly, it should be corrected slowly, and that dehydration and hypovolemia are not synonymous. Giving a fluid bolus for a patient who is dehydrated but not hypovolemic is contraindicated; it will not restore their interstitial deficit any faster and will damage the endothelial glycocalyx in the process.

Once you have calculated an estimated fluid deficit, estimate the patient’s maintenance needs as discussed above. Be sure to take into account any comorbidities, such as known cardiac disease, hypoalbuminemia, or any other factors that may predispose the patient to fluid overload. When in doubt, err on the side of caution and choose a lower rate (you can always give more fluid—it is much harder to take it back).

Finally, estimate the patient’s ongoing losses. If the patient has a urinary catheter in place, this can easily be used to quantify urine output every 4 to 6 hours. However, it is more difficult to estimate other kinds of losses, such as those from the intestinal or respiratory tract. In smaller patients, it may be helpful to weigh used potty pads and subtract the original weight of the pad (the difference in kg is equal to the volume lost in liters). One of the easiest ways to measure fluid balance is simply to weigh the patient every 12 hours.

Other parameters that should be monitored include vital signs and mentation, blood pressure, PCV/TS, renal values, urine-specific gravity, blood gas and base deficit, serum lactate,

 and AFAST/TFAST (abdominal and thoracic focused assessment with sonography for trauma, triage, and tracking, especially if there are concerns about third spacing).

Once you have determined these parameters, you can calculate your fluid rate as follows:

fluid rate = (volume of dehydration in liters/number of hours to correct dehydration) + (maintenance rate) + (estimated ongoing losses). Once you have a final rate, be sure to ask yourself whether the fluid rate is appropriate for your patient’s weight. In general, it is not recommended to exceed rates of 2 to 3 mL/kg/h in cats or 2 to 6 mL/kg/h in dogs.

The most important part of making a fluid plan is to reassess. Fluid therapy is not one-size-fits-all. Pay attention to the parameters listed above and adjust as needed. For instance, if a patient comes in with a PCV/TS of 65/9.0 and a lactate level of 5mmol/L, but after 12 hours on fluids these numbers drop to 50/6.0 and 1.8 mmol/L, respectively, then that patient’s hydration status has significantly improved and the fluid rate should be adjusted accordingly. It is inevitable that potassium levels will decrease even in a healthy animal on fluids, but this is especially true in patients with disease states such as diabetic ketoacidosis or chronic kidney disease. Be sure to recheck electrolytes every 6 to 12 hours and add potassium as indicated.

Part 3: The approach to the critical patient and the role of the endothelial glycocalyx

Administering fluids to an overall healthy patient, such as one undergoing ovariohysterectomy or a dental procedure, differs tremendously from administering fluids to an ill patient. In addition to dealing with replacing volume deficits and treating shock, these patients have underlying conditions that often set off a systemic inflammatory cascade and predispose them to complications from fluid therapy. Restoring homeostasis in these patients is a challenge, and their specific needs can change by the hour or even the minute.

Rapid assessment of a critical patient’s perfusion parameters upon their arrival at the clinic is imperative to determine whether clinical signs of hypovolemia are present, what interventions are necessary, and to monitor the patient’s response to treatment. Hypovolemic patients will exhibit signs of hypoperfusion, including tachycardia (progressing to bradycardia in later stages of shock, and bradycardia is more common in cats), hypothermia, poor pulse quality, changes in mucous membrane color (pallor, gray/muddy), hypotension, and dull mentation. It is important to rule out cardiogenic shock as a cause of hypoperfusion, because fluid administration to patients in heart failure will worsen their disease state. If there is the presence of a heart murmur or gallop rhythm, dyspnea, abnormal lung sounds, or jugular distension, thoracic radiographs should be performed prior to making the decision as to whether fluid therapy is necessary. Any patient exhibiting signs of hypoperfusion should be provided flow-by oxygen immediately upon arrival.

If cardiogenic shock is ruled out, fluid resuscitation can be initiated while additional diagnostics are being performed. The shock volume in dogs is ~90 mL/kg, and in cats ~60 mL/kg.

 The recommendation is to administer a quarter of the shock volume (ie, approximately 20-25 mL/kg in dogs, 10-12 mL/kg in cats) over 20 minutes and reassess the patient’s perfusion parameters upon completion of the bolus.

In most cases, more information will be available after 20 minutes on completion of point-of-care ultrasound and blood work. At this point, you can determine whether additional boluses or other treatments, such as blood products, are necessary.

If you have determined that a patient is neither interstitially dehydrated nor hypernatremic, but still exhibiting signs of hypovolemia, it is reasonable at this point to administer a dose of HSS. HSS can be especially helpful in patients showing signs of acute hemorrhage (ie, trauma, hemoabdomen), because volume-restricted resuscitation is advocated to prevent dislodgement of any blood clots and potentially worsened hemorrhage. In many cases, administering a single 20 mL/kg crystalloid bolus along with 4 to 5 mL/kg of HSS will help maintain a systolic blood pressure between 60 and 90 mmHg (permissive hypotension) until blood products can be administered and the patient can proceed to surgery. HSS should also be considered as part of a low-volume resuscitation protocol in patients with head trauma.

If a patient is determined to be septic, crystalloid boluses at 10 to 20 mL/kg can be administered while hemodynamic variables are being monitored. If half of the shock dose has been administered and there is still significant hypotension, early vasopressor therapy should be considered.

These guidelines are based on multiple human studies, because there are no currently available guidelines regarding the use of IV fluids in animals with septic shock. Again, avoidance of the use of synthetic colloids in septic patients is important to prevent AEs associated with such products.

In the resuscitative phase of fluid therapy, frequent monitoring and reevaluation of perfusion parameters is important to determine the response to therapy and avoid fluid overload.

 In addition to the physical examination parameters listed above, other end points that can be used to evaluate perfusion more objectively include lactate, base deficit, and oxygen-transport variables. In human medicine, multiple studies have shown that reliance on traditional end points of resuscitation alone are insufficient in evaluating ongoing tissue hypoxia. Methods such as gastric tonometry, which specifically evaluate the perfusion of regional tissue beds, are also helpful in evaluating hypoxia, but many of these methods are not readily available in most veterinary settings. In critically ill patients, it is important to not only monitor traditional end points including blood pressure, heart rate, body temperature, capillary refill time, and urine output, but to also recheck values such as lactate, base deficit, blood gas analysis, and pulse oximetry with relative frequency, until these parameters begin to normalize.

Targeted end points of resuscitation in patients with shock include the following: systolic blood pressure, 80 to 100 mmHg; mean arterial pressure, 60 to 80 mmHg; base deficit –2 to 2 mEq/L; lactate 1 plus or minus 0.5 mmol/L; SvO2 greater than 70%; and pH greater than 7.32.

What is the endothelial glycocalyx and why is it important?

The endothelial glycocalyx has garnered much attention in recent years, and for good reason. The endothelial glycocalyx is a gel-like matrix that lines all vascular endothelial surfaces. It is composed of glycosaminoglycans, proteoglycans, and glycoproteins. It is a dynamic structure that has many functions, including hemostasis, inhibition of microthrombosis, regulation of adhesion and migration of leukocytes through endothelial cells, regulation of vascular tone and permeability, and regulation of fluid flux across endothelial cells. Many plasma proteins interact with the endothelial glycocalyx, including albumin, antithrombin III, and superoxide dismutase.

The results of damage to the endothelial glycocalyx can be catastrophic. Increased vascular permeability leads to capillary leakage and edema. Dysregulated cell-cell interactions lead to a proinflammatory and hypercoagulable state. Normal vascular reactivity and vessel tone are compromised. Shedding of the endothelial glycocalyx layer plays a prominent role in the pathophysiology of various critical illnesses, and care should be taken to reduce its damage.

There are many potential causes of damage to the endothelial glycocalyx, including sepsis and systemic inflammatory response syndrome, hemorrhage, hyperglycemia, ischemia-reperfusion injury, and hypervolemia. In the context of this article, it is important to understand that a hypervolemic state (fluid overload) leads to endothelial glycocalyx disruption. In addition, rapid administration of crystalloids or colloids can increase endothelial glycocalyx shedding.

 Therefore, it is important to always determine whether a fluid bolus is required in the first place, and why it is important to always be reevaluating a patient’s response to fluid therapy.

Many investigative studies have explored possible therapies to preserve or repair the endothelial glycocalyx. At this time, there does not appear to be one particular therapy that is strongly recommended, nor is there any available research specific to veterinary medicine. Treatments that have shown promise include early blood product administration, matrix metalloproteinase inhibitors, albumin, exogenous glycosaminoglycans, activated protein C, sulodexide, and heparin.

Because little is known about these treatments and many of them are not readily available, our best option as veterinary professionals is to make every effort to avoid further damage to the endothelial glycocalyx. A judicious, calculated approach to fluid therapy should be taken with every patient.

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https://todaysveterinarypractice.com/fluid-therapy-in-critical-care/

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https://www.dvm360.com/view/crystalloids-or-colloids

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Lat, I., Coopersmith, C.M., De Backer, D. et al. The surviving sepsis campaign: fluid resuscitation and vasopressor therapy research priorities in adult patients. ICMx 9, 10 (2021). 

https://doi.org/10.1186/s40635-021-00369-9

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Knowing how to approach critical patients is key.

Fluid therapy and the role of the endothelial glycocalyx

Ellie Virtue, BSc, MiF, PhD, will use her knowledge and expertise in the animal health industry to help her succeed as the AniV8 CEO. (Photo courtesy of AniV8).

AniV8—a leading developer of clinical sensor technology to diagnose and monitor diseases in pets—has appointed Ellie Virtue, BSc, MiF, PhD, as the new CEO of the company. Virtue joins the AniV8 team with 15 years of scientific and commercial expertise within the animal health industry including the development of human and animal health pain therapeutics.

“Ellie’s commercial and business expertise, combined with a strong background in animal health and the develop­ment of novel osteoarthritic pain therapeutics, make her the ideal candidate to drive the development of AniV8’s unique monitoring technology,” says B Duncan X Lascelles, BSc, BVSc, PhD, FRCVS, CertVA, DSAS(ST), DECVS, DACVS, cofounder and chief scientific advisor member of the Board of AniV8 and professor at North Carolina State University, in a company 

“We believe AniV8’s lead product has the potential to revolutionize the management of many companion animal diseases, facilitating earlier diagnosis and the optimization of treatment strategies,” he adds.

According to the release, Virtue wields a Master of Applied Finance (MAF) from Macquarie University and a PhD from the University of Melbourne. Prior to becoming CEO of AniV8, Virtue was a venture partner at Stonehaven Incubate—one of AniV8’s founding partners—where she identified and developed innovative human health technologies with potential for the animal health market.

Additionally, she contributed to therapeu­tic treatments for osteoarthritic pain in companion animals at Nexvet Biopharma. As the business went from a small start-up to a NASDAQ-listed global company, Virtue’s roles and capabilities advanced across R&D, operations, alliance management, and business development.

“AniV8’s clinical sensor technology is underpinned by ground-breaking data science and movement metrics and is aimed at easing the unnecessary suffering of pets through early diagnosis that will enable more appropriate treatment,” says Virtue in the release.

“Our immediate focus is on bringing AniV8’s first product, to diagnose and monitor osteoarthritis pain in dogs and cats, to the market as quickly as possible. It can take many years before dogs and cats show obvious signs of pain, and this wearable technology would enable pet owners and veterinarians to assess problems more rapidly and to identify if treatment options are effective. I look forward to working with the excellent team at AniV8 to unlock the full potential of this much-needed innovation,” she adds.

Dr Ellie Virtue’s experience in the animal health field can help fuel the development and commercialization of the first-of-its-kind wearable monitor that will detect osteoarthritis pain in companion animals. 

AniV8 appoints new CEO

Veterinary medicine has long eclipsed human medicine in terms of the speed of diagnostic results and return calls to clients. Most recently, in-clinic digital cytology scanners from Antech and IDEXX have been further speeding the process and adding efficiency to the industry by yielding fast results, connecting veterinarians to pathologists, and improving client adherence and satisfaction. Learn more about the benefits of these scanners and their technology as outlined below.

The accuracy of digital cytology scanners

Excellent images allow pathologists to interpret with ease. No significant differences have been noted between digital and glass slides regarding the number of cases correctly diagnosed or the sensitivity, specificity, or diagnostic accuracy, irrespective of the observer’s expertise. Digital slides produced by the whole-slide imaging scanner are adequate to diagnose cytological samples and are similar among clinical pathologists with differing levels of expertise.

 Additionally, when it comes to comparison of human to veterinary implementation of digital pathology, guidelines for validating scanners are certainly more than comparable on the veterinary side.

Whole-slide interpretations from diagnostic labs Antech and IDEXX have a rapid turnaround time of 2 hours—24/7, 365 days a year. Although IDEXX launched its in-clinic cytology reader at the Veterinary Meeting & Expo in 2020, Antech’s was launched earlier this year.

Sarah Johnson, DVM, MS, DACVP, assistant chief medical officer of clinical pathology at Antech, said, “We’ve been reading digital hematology for years and we have now transitioned to digital cytology, both at the reference lab level and with our in-hospital digital cytology scanners. There were some absolute necessities before we could feel confident with our units; they are user friendly, quick to scan, able to easily pick up on intricate details with image quality similar to a microscope, and there are no parts that can easily break, such as a slide loading cartridge.”

Penny Guyton, senior director of global product management for IDEXX Reference Labs, said, “Our customers have been so impressed, particularly during the pandemic when clients are waiting curbside in cars or dropping off a pet, and then by the time they run some errands the cytology is back. Veterinarians feel good about this—offering answers quickly.”

IDEXX and Antech are able to manage this 2-hour-or-less turnaround time even in the wee hours because a pathologist does not receive a 3 AM wake-up call from a criticalist in New York City. Instead, a pathologist in Australia may read the results in real time.

Speed is not the only benefit of the digital cytology scanners. Another advantage is the pathologist’s ability to solicit a second pathologist’s opinion nearly instantaneously.

Zachary Wright, DVM, DACVIM (oncology), chair of the VCA (Veterinary Centers of America Inc) Pet CancerCare Alliance, said, “The [Antech] cytology scanner has dramatically improved the efficiency in our workflow. We now often call clients with cytology results before they get home from their appointment. Also, for intraoperative cases it allows for a more accurate diagnosis in challenging cases that require the clients to make life-or-death decisions quickly. Lastly, the digital nature of the cytology allows for sharing among pathologists and I often get 3 or 4 opinions on challenging cases, which improves our confidence in the diagnosis.”

Additionally, client adherence has improved. Guyton pointed out that in some rural places it is ideal to have clients remain in the parking lot or in the clinic with the pet until the results return because their ride home takes 2 hours. With the client remaining in the vicinity when the results come back, treatment can start or at least a treatment plan can be created.

Johnson offered a real-life example. “A dog comes in for a wellness visit, and the veterinarian notes a lymph node should be aspirated. This is, of course, common. The dog didn’t seem ill, and indeed has no signs. Rather than say, ‘We’ll just watch and wait until the next visit’ (arguably not the best medicine) or ‘I’ll let you know in a couple of days,’ when results are going to come in so fast, clients are—by human nature—more likely to say, ‘Go ahead [with treatment].’ And if treatment is suggested, that treatment can start now. Certainly, this is to a pet’s benefit.”

The nearly instant results also may help clients sleep better—instead of returning home with their pet wondering and waiting for the results. And even if the news from the cytology is not great, the veterinarian can explain the next steps face to face.

Johnson said sometimes clients are ready to euthanize a beloved pet. “Here’s something I’ve seen: the in-clinic cytology scanners saved lives. A dog is vomiting and has enlarged lymph nodes all over. I’m thinking lymphoma, but the cytology says otherwise, and it turns out to be salmon poisoning disease

(one example of a medical condition often mistaken for lymphoma [but not nearly as costly as treating lymphoma]).” Therefore, clients are more likely to go forward with treatment rather than euthanizing their pet due to factors such as cost, age, the progression of the disease, the scary cancer world, etc.

Guyton said, “The in-clinic scanners are to everyone’s benefit; the veterinary clinic feedback we’ve received, so far, is 100% positive, that’s 100%. But also, clients, of course, want instant answers and they get it. Most important, the pets benefit. This is a path on the way to AI [artificial intelligence] for sure. This [technology] is ripe for AI, and exciting to see what’s next.”

Bonsembiante F, Bonfanti U, Cian F, Cavicchioli L, Zattoni B, Gelain ME. Diagnostic validation of a whole-slide imaging scanner in cytological samples: diagnostic accuracy and comparison with light microscopy. 

. 2019;56(3):429-434. doi:10.1177/0300985818825128

Pantanowitz L, Sinard JH, Henricks WH, et al; College of American Pathologists Pathology and Laboratory Quality Center. Validating whole slide imaging for diagnostic purposes in pathology: Guideline from the College of American Pathologists Pathology and Laboratory Quality Center. 

Booth AJ, Stogdale L, Grigor JA. Salmon poisoning disease in dogs on southern Vancouver Island. 

With the release of Antech’s and IDEXX’s in-clinic digital cytology scanners, veterinary professionals can deliver fast results to clients and connect with pathologists like never before. 
