pH In Dogs Research Articles

Pharmacodynamics of 2 dosages of orally administered esomeprazole in client-owned, healthy dogs: A prospective, crossover study.

Esomeprazole use is increasing in dogs, but the gastrointestinal adverse events associated with q12h dosing necessitate pharmacodynamic evaluation of a reduced dose and frequency of administration. To compare the efficacy of 2 doses of (q24h) esomeprazole in raising intragastric pH in dogs. Nine healthy, client-owned dogs, >20 kg. Prospective, randomized, double blinded, crossover study. Esomeprazole (0.5 or 1 mg/kg q24h) was orally administered for up to 5 days per treatment arm, and the mean percentage time intragastric pH was ≥3 (MPT3) and ≥4 (MPT4) for 24 hours periods were compared to pretreatment pH using a continuous pH monitoring system. Dogs failing to reach pH goals (MPT3 ≥75%, MPT4 ≥66%) with once daily dosing received esomeprazole 1 mg/kg PO q12h to determine if a higher dose would improve acid suppression. No significant difference in the MPT3 or MPT4 was identified between treatments for any time point (P > .05). Both doses increased the MPT pH ≥3 and 4 median [range] (0.5 mg/kg, 1 mg/kg) on days 1 (MPT3: 76.8% [44-100], 69.2% [28.2-100]; MPT4: 65.6% [16.7-99.3], 54.9% [14.9-93.3]; P = .0009) and 2 (MPT3:77.2% [27.4-100], 75.4% [49.4-89.5]; MPT4: 66.3% [15.5-100], 59.7% [33.8-81.2]; P = .0005) of PPI treatment compared to pretreatment (MPT3: 58.3% [0.02-93.9], 52.6% [6.1-94.7]; MPT4: 25.2% [0-86.8], 32.4% [1.8-89.3]). Six dogs (66%, [0.36, 0.97]) reached pH goals established in humans with q24h dosing. Both q24h PO esomeprazole doses were effective in raising intragastric pH, despite high intersubject variability, but 33% of dogs required q12h dosing to reach pH goals.

Effects of two commercial diets and two supplements on urinary pH in dogs.

Urinary pH manipulation by therapeutic foods or supplements is part of the treatment for urolithiasis. The effectiveness of these diets and supplements should be studied to determine which of these strategies is most effective. To assess the effect of the oral supplementation of potassium citrate, an ammonium chloride solution (Urical) and two dry therapeutic foods-Hill's® Prescription Diet® u/d® Canine (u/d diet) and Royal Canin® Urinary S/O dog (S/O diet)-on a dog's urinary pH at different time points over 8 h. Seven healthy adult male research beagle dogs. A prospective interventional study lasting 31 days. The dogs either received a supplement (potassium citrate or rical) with a dry adult maintenance diet (control diet) or the therapeutic diet (u/d diet or S/O diet). Each treatment had a duration of 2-5 days, with 2- to 4-day washout periods in between. Urinary pH measurements were performed every 2 h between 07h00 and 15h00, with the food being given at 07h00 and 15h00, right after urine collection. The pH measurements obtained in each of the four treatments were compared to control (same dogs fed the control diet exclusively). When compared to the control diet at the same time points, biologically relevant changes in urinary pH (defined as ≥0.5) were: increase with potassium citrate at 7h00 and 13h00; increase with u/d diet at 9h00, 13h00, and 15h00; decrease with S/O diet at 9h00 and 11h00; Urical did not have a detectable effect on urinary pH. The present study confirms that therapeutic foods S/O and u/d, and potassium citrate supplement affected acid-base balance in healthy adult male beagle dogs, with the tested diets being more effective than the administered doses of the tested supplements at influencing urinary pH.

Apparent total tract digestibility and palatability of extruded diets with graded levels of whole soybeans by dogs.

Fat has high energy density and is considered one of the primary energy sources for dogs, however, increasing fat level in dry dog food has been challenging due to the lubrication and limitation of the coating system. The objective was to determine the effect of whole soybeans (WSB) on nutrient digestibility, stool quality, and palatability by dogs. The corn gluten meal, chicken fat, and brewers rice were replaced by WSB at 10, 20, and 30% (WSB10, WSB20, and WSB30, respectively) in the base diet (WSB0). Twelve beagles were randomly assigned. The digestibility trial was duplicated 4 × 4 Latin square design where dogs were allowed a 9-d adaptation followed by a 5-d total fecal collection for each period. Least-square means were analyzed with a single degree of freedom contrasts and significance at α = 0.05. Palatability was determined with a 2-bowl test by 20 beagles for 2 d with each WSB diet compared to the WSB0. First choice preference between two diets and total food consumption were recorded. Individual intake ratios (IR) were calculated (intake of each diet/total intake) for each dog. First choice (FC) was analyzed by a Chi-square probability, and the diet consumption was compared by a Wilcoxon signed rank test and a 2-way analysis of variance. Fecal moisture, output, and defecation frequency increased linearly (P < 0.05) as WSB increased. Apparent total tract digestibility of dry matter, organic matter, crude protein, fat, and gross energy decreased linearly (P < 0.05) as dogs fed the increased level of WSB. The fresh fecal pH in dogs decreased linearly (P < 0.05) as WSB content increased. The acetate, propionate, and the total short-chain fatty acid concentration increased linearly (P < 0.05) while the total branched-chain fatty acid concentration decreased linearly (P < 0.05) as WSB increased. Dogs had greater (P < 0.05) FC for WSB diets than WSB0, but there was no difference among treatments for diet consumption and IR. In conclusion, additional thermal processing before extrusion may improve nutrient digestibility of WSB. The stool quality and palatability were not affected, and fermentation in hindgut increased by WSB by dogs.

Gastrointestinal transit time is faster in Beagle dogs compared to cats.

To characterize gastrointestinal transit times (GITTs) and pH in dogs, and to compare to data recently described for cats. 7 healthy, colony-housed Beagles. The GITTs and pH were measured using a continuous pH monitoring system. For the first period (prefeeding), food was withheld for 20 hours followed by pH capsule administration. Five hours after capsule administration, dogs were offered 75% of their historical daily caloric intake for 1 hour. For the second period (postfeeding), food was withheld for 24 hours. Dogs were allowed 1 hour to eat, followed by capsule administration. Both periods were repeated 3 times. The GITTs and pH were compared to published feline data. The mean ± SD transit times in dogs for the pre- and postfeeding periods, respectively, were esophageal, 3 ± 5 minutes and 13 ± 37 minutes; gastric, 31 ± 60 minutes and 829 ± 249 minutes; and intestinal, 795 ± 444 minutes and 830 ± 368 minutes. The mean ± SD gastrointestinal pH in dogs for the pre- and postfeeding periods, respectively, were esophageal, 6.6 ± 0.6 and 5.7 ± 1.0; gastric, 3.0 ± 1.4 and 1.8 ± 0.3; intestinal, 7.9 ± 0.3 and 7.7 ± 0.6; first-hour small intestinal, 7.6 ± 0.5 and 7.1 ± 0.4; and last-hour large intestinal, 7.9 ± 0.6 and 7.7 ± 1.0. The first-hour small intestinal pH and total transit times varied between dogs and cats depending on feed period (P = .002 and P = .04, respectively). Post hoc analysis revealed significantly shorter total transit times in dogs prefeeding (P = .005; mean ± SD for cats, 2,441 ± 1,359 minutes; for dogs, 828 ± 439 minutes) and postfeeding (P = .03; mean ± SD for cats, 3,009 ± 1,220 minutes; for dogs, 1,671 ± 513 minutes). Total transit time for dogs was also shorter pre- versus postfeeding (P = .003). GITT is faster in Beagles compared to cats, but gastrointestinal pH are similar when fed the same diet.

Strongly acidic gastroesophageal reflux and esophageal lumen pH before and after esophageal lavage with water or two bicarbonate concentrations in anesthetized dogs.

To increase acidic esophageal lumen pH in dogs that developed gastroesophageal reflux (GER) during anesthesia. We compared water and 2 different bicarbonate concentrations. 112 healthy, nonbrachycephalic dogs presented for ovariectomy. Following standard anesthesia and surgery protocols for ovariectomy in all dogs, esophageal lumen impedance and pH were monitored using a dedicated probe. Esophageal impedance indicates the presence of GER whereas pH indicates the acidity level. Dogs with strongly acidic GER and an esophageal lumen pH value < 4.0 were included in the study, and lavage was performed with either tap water, bicarbonate 1%, or bicarbonate 2% until the pH increased to > 4.0. The effect of lavage on esophageal pH was compared using the Kruskal-Wallis and Wilcoxon 2 sample tests. Associations between lavage and pH changes were determined. Of 48/112 dogs with strongly acidic GER, 33% neutralized their esophageal pH during surgery. For the 32 dogs that maintained an esophageal lumen pH value < 4, esophageal lavage with water increased the lumen pH to > 4 in 78.6% of dogs, whereas both bicarbonate concentrations increased it in 100% of the dogs to a more neutral pH (P < .0001). The dogs in the water group were more likely to regurgitate after anesthesia (36% vs 0% in both bicarbonate groups, P = .028). Bicarbonate 1% and 2% increased esophageal lumen pH to more than 4 after strongly acidic GER. Lavage with water was mildly effective, but required large volumes and predisposed to further regurgitation after anesthesia.

Perineal herniorrhaphy with pedunculated tunica vaginalis communis in dogs: Description of the technique and clinical case series.

BackgroundPerineal hernia (PH) in dogs is caused by the separation of the anal septal muscles and the displacement of pelvic/abdominal organs under the perineal skin. Reconstruction of the pelvic septum by surgical repositioning is the only curative treatment.ObjectivesTo describe the procedure and outcomes of surgical repair using the pedunculated tunica vaginalis communis (TVC) for PH in dogs.MethodsIntact male dogs diagnosed with PH were included in this study. For surgery, each dog was positioned in the Trendelenburg position. Castration was performed with the open technique, followed by colopexy and cystopexy via laparotomy. The remaining bilateral TVCs transposed to the opening of PH were used for the perineal herniorrhaphy. Intraoperative findings, complications, and outcomes were evaluated and recorded.ResultsEight dogs [median age 10.5 years (range, 9–13 years); median body weight 4.9 kg (range, 1.6–12.3 kg)] were treated using the TVC surgical technique. Perineal herniorrhaphy with the TVC was feasible in all dogs. The median operation time was 105.5 min (range, 46–149 min) in unilateral PH, and 92 and 122 min in two dogs with bilateral PH. Short-term postoperative complications during hospitalization did not occur in six dogs, whereas the residual two dogs had a temporary local infection as a minor complication. Postoperative recurrence occurred in one dog (13%) on postoperative day 136.ConclusionsOur study suggests that the herniorrhaphy technique using the pedunculated TVC is an alternative option for the repair of PH in dogs.

Effect of an ear cleaner instillation containing lipacids in a model of re-acidification of the external auditory canal in dogs.

BackgroundIn humans, the acidic pH of the ear canal plays a protective role against infection and a change towards alkalinity of the external auditory canal (EAC) is a local factor in the progression of acute to chronic otitis externa (OE). The use of acidic preparations alone for treatment of OE without concurrent antibiotic use is well‐documented in humans. In dogs, only one study has investigated the EAC pH in healthy dogs and in dogs with OE, and investigations to understand the role of EAC pH in the pathogenesis of canine OE are lacking.Hypothesis/objectivesTo obtain physiological EAC pH values in beagle dogs. To develop a model of re‐acidification of the EAC in dogs and to investigate how an acidic solution may accelerate the return to a physiological pH.AnimalsTen healthy beagle dogs in a laboratory setting.Materials and MethodsA model of re‐acidification of the EAC was developed by instillation of a pH 10.1 phosphate‐buffered saline (PBS) solution and the subsequent acidic effect of an ear cleaner containing lipacids was evaluated in this model.ResultsMean physiological EAC pH was 6.12 (± 0.36). EAC re‐acidification took up to 9 h in this model. Mean pH values dropped immediately to 6.38 (± 0.27) on ears treated with an acidic ear cleaner. No abrupt drop was observed of the mean pH values for the control ears.Conclusion and clinical importanceThis study confirms that physiological EAC pH in dogs is acidic. This model of re‐acidification of the EAC pH allows investigations on acidic properties of topical ear products in healthy ears.

Influence of age, sex, body condition score, rectal temperature, anatomical location and hair on skin pH in dogs.

Physiological skin pH levels are well-documented in human medicine, and assessment of variations may be important in assessing the efficacy of wound healing. By contrast, physiological skin pH levels in dogs are sparsely described. To determine the pH of intact skin in healthy dogs and to study the influence of different physiological factors on the pH level of canine skin. Seventy-seven client-owned dogs of various breeds, age and sex. A prospective study was designed and the pH of intact skin was measured at the concave surface of both pinnae, and in both axillary and inguinal regions. For each location, the colour and density of the hairs also was recorded. Each dog's rectal body temperature and body condition scores also were determined. The skin pH in dogs <12 weeks of age was significantly lower (3.97-5.70) than in older dogs (4.40-8.18) (P < 0.001). In dogs >12 weeks of age, skin pH was significantly lower in the inguinal regions compared to the pinnae (P = 0.008), and female dogs had a significantly lower skin pH in the inguinal regions than male dogs (P = 0.043). Pinnae covered with light-coloured hair had a lower skin pH than those with dark-coloured hair (P = 0.04). No significant differences were found between dogs with different body condition scores, body temperatures or differences in hair density. The pH of intact healthy skin is lower in puppies of <12 weeks of age. Regional differences of body location also were seen which were variably affected by hair colour and sex. A baseline assessment of skin pH in healthy dogs is important for future studies of disease and wound healing.

The prevalence of pulmonary hypertension assessed using the pulmonary vein\u2010to\u2010right pulmonary artery ratio and its association with survival in West Highland white terriers with canine idiopathic pulmonary fibrosis

BackgroundPulmonary hypertension (PH) is a known co-morbidity in West Highland white terriers (WHWTs) affected with canine idiopathic pulmonary fibrosis (CIPF). The pulmonary vein-to-right pulmonary artery ratio (PV/PA) has recently been described for the detection of pre-capillary PH in dogs. The objective of the present study was to estimate the prevalence of PH at diagnostic, in WHWTs affected with CIPF, by using PV/PA, in comparison with a group of healthy breed-matched controls (CTRLs). Additional study objective was to explore whether the presence of PH at initial diagnosis of CIPF impacted survival time in dogs treated with sildenafil.ResultsTwenty-five client-owned WHWTs presented with CIPF and 19 CTRLs were included in the study. PV/PA in either two-dimensional mode (2D) or time-motion mode or both were measured from cineloops in each dog. Dogs were classified according to PV/PA value into non/mild PH (PV/PA measured in 2D ≥ 0.7) or moderate/severe PH (PV/PA < 0.7). Survival data of WHWTs affected with CIPF were extracted from medical record to assess association between presence of PH at diagnosis and outcome. 60 % overall prevalence for moderate/severe PH was estimated in this cohort of WHWTs presented with CIPF vs. 5 % in CTRLS (P = 0.0002). The presence of moderate/severe PH at initial presentation was not associated with survival.ConclusionsResults of the present study confirm a high prevalence of PH at diagnosis in WHWTs affected with CIPF and highlight the utility of PV/PA as a non-invasive surrogate for assessment of PH in this population.

A prospective, randomized, masked, placebo-controlled crossover study for the effect of 10 mg omeprazole capsules on gastric pH in healthy dogs.

BackgroundEnteric‐coated omeprazole capsules are commonly used as a gastric acid suppressant in dogs. However, the efficacy of this formulation has not been evaluated for clinical use in dogs.Hypothesis/ObjectivesTo evaluate the efficacy of a 10 mg PO omeprazole capsule (TriviumVet) undergoing FDA approval to increase gastric pH in dogs. We hypothesized that encapsulated omeprazole would significantly increase the gastric pH compared to placebo and reach pH goals extrapolated from people for the treatment of esophagitis and duodenal ulceration.AnimalsSix healthy research dogs.MethodsRandomized, blinded, 2‐way crossover study. Dogs were PO administered omeprazole at 0.5 to 1.0 mg/kg or placebo (empty gelatin capsules) twice‐daily for 5 days. The intragastric pH was recorded on days 2 to 5 of treatment. Mean pH and the mean percentage time (MPT) intragastric pH was ≥3 or ≥4 were compared between and within treatment groups.ResultsDogs treated with omeprazole had a significantly higher MPT ± SD intragastric pH ≥3 (91.2% ± 11.0%), ≥4 (86.9% ± 13.7%) and mean ± SD pH (5.4 ± 0.8) than dogs treated with placebo (19.7% ± 15.5%, 28.3 ± 20.7, and 2.4 ± 1.0, respectively) (P < .001 for all).Conclusions and Clinical ImportanceThe 10 mg enteric‐coated omeprazole capsule PO administered evaluated in this study is an effective gastric acid suppressant in healthy dogs.

Clinical, Hematological, Blood Gasometric and Electrolytic Changes in Dogs Receiving Whole Blood Transfusions

Background: Blood transfusion is a tool capable of saving lives. Patients undergoing blood transfusion usually present several alterations in the acid-base and electrolyte balance, aggravating the condition of critically ill patients. Some studies have demonstrated haematological alterations in certain species that received whole blood transfusions, however, few studies have evaluated acid base and electrolyte changes in dogs undergoing whole blood haemotherapy. The aim of this study was to analyze clinical, hematological, blood gas and electrolyte changes in anemic dogs after whole blood transfusion.Materials, Methods &amp; Results:Twenty nine dogs transfused due to anemia were enrolled in the study. Donors blood was collected in a transfusion bag containing citrate phosphate adenine dextrose and stored up to 24 h. Blood collections and evaluations were made before and 24 h after the transfusion. Data distribution normality was tested by the Shapiro Wilk Test. The means of the variables were compared by paired t-test. It was observed an increase in diastolic blood pressure and a reduction in heart rate (P &lt; 0.05). There was a not significant increase in systolic blood pressure, temperature, and a reduction in respiratory rate per minute. Erythrocyte, haemoglobin and haematocrit averages were significantly increased after blood transfusion (P &lt; 0.05). It was observed a reduction in the mean values of pH (P &lt; 0.05), potassium (P &gt; 0.05) and ionized calcium (P &gt; 0.05) and an increase in the mean partial pressure of carbon dioxide (pCO2) (P &lt; 0.001), bicarbonate (P &gt; 0.05) and sodium (P &lt; 0.05). The probable cause of anemia was monocytic ehrlichiosis (14/29), visceral leishmaniasis (1/29), babesiosis (1/29), co-infection of Ehrlichia canis and Leishmaniainfantum (2/19), co-infection of E. canis and Babesia vogeli (1/19). It was not possible to determine the etiology of the anemia in ten dogs. Discussion:Heart rate significantly reduced after transfusion, probably because of the increase in hematocrit, hemoglobin and erythrocyte values. It may be justified by the displacement of extravascular fluid to the intravascular space. Mean values of systolic blood pressure were slightly elevated before transfusion and remained elevated afterwards, while diastolic and mean arterial pressure increased significantly after transfusion. These changes may be due to the morbid condition and may be influenced by many other factors. Haematocrit, haemoglobin and erythrocyte values increased significantly after transfusion, according to what was observed in other studies. The significant reduction in pH and increase in pCO2 reflects the compensatory mechanism for metabolic acidosis to increase ventilation, leading to pCO2 reduction and changes in pH. The reduction in pH due to the contact of the collected blood with conservative solutions is one of the main changes thar occurs during blood storage. It was described significantly lower pH in dogs’ whole blood samples stored for more than 24h in vacutainer plastic containing CPDA-1. We may assume there was no intense pH reduction in the present study because the bags were stored for up to 24 h. Although not statistically significant, the increase of pO2 mean reflects the improvement of tissue oxygen perfusion. It was observed a significant increase in sodium ions. The mean sodium ionconcentration before transfusion was very close to the maximum reference value. Hyperkalaemia was not observed, nor was there significant reduction of potassium ions after transfusion. Several studies report hyperkalaemia and transfusion-associated cardiac arrests in humans, associated with infusion of large volumes of blood. Whole blood transfusion increased erythrogram values and did not negatively affect the electrolyte or acid-base status, representing a safe and useful tool in the intensive care of small animals.

Comparative analysis of the effect of IV administered acid suppressants on gastric pH in dogs.

BackgroundUpper gastrointestinal (GI) ulceration and bleeding in critically ill dogs can cause severe anemia and increase morbidity. Acid suppressants using proton pump inhibitors or histamine‐2 receptor blockers administered IV is commonly recommended.Hypothesis/ObjectivesTo evaluate the efficacy of IV administered esomeprazole, pantoprazole, and famotidine constant rate infusion (CRI) on increasing the intragastric pH of dogs. We hypothesized that esomeprazole and famotidine CRI would provide superior acid suppression compared to pantoprazole and reach pH goals for the treatment of GI bleeding.AnimalsNine healthy research Beagles.MethodsRandomized, 3‐way crossover. Dogs received pantoprazole or esomeprazole at 1 mg/kg IV q12h and famotidine with a loading dose of 1 mg/kg followed by 8 mg/kg IV CRI daily for 3 consecutive days. The intragastric pH was recorded at baseline and for 72 hours of treatment. The mean pH and the mean percentage time (MPT) the intragastric pH was ≥3 or ≥4 were compared among and within treatment groups.ResultsSignificant increases in mean pH (P < 0.0001), MPT ≥3 (P < 0.001), and MPT ≥4 (P = 0.0006) were noted over time with all 3 treatments. The time effect did not differ by treatment for mean pH, MPT ≥3, and MPT ≥4 (P = .29, .56, and .37, respectively); however, only esomeprazole and famotidine CRI achieved the goals established for the treatment of gastroduodenal ulceration in people.Conclusions and Clinical ImportanceFamotidine CRI and esomeprazole might be superior acid suppressants compared to standard doses of pantoprazole for the first 72 hours of treatment.

Effect of hospitalization on gastrointestinal motility and pH in dogs.

OBJECTIVE To determine the effect of hospitalization on gastrointestinal motility and pH in healthy dogs. DESIGN Experimental study. ANIMALS 12 healthy adult dogs. PROCEDURES A wireless motility capsule (WMC) that measured pressure, transit time, and pH within the gastrointestinal tract was administered orally to dogs in 2 phases. In the first phase, dogs received the WMC at the hospital and then returned to their home to follow their daily routine. In the second phase, dogs were hospitalized, housed individually, had abdominal radiography performed daily, and were leash exercised 4 to 6 times/d until the WMC passed in the feces. All dogs received the same diet twice per day in both phases. Data were compared between phases with the Wilcoxon signed rank test. RESULTS Data were collected from 11 dogs; 1 dog was excluded because the WMC failed to exit the stomach. Median gastric emptying time during hospitalization (71.8 hours; range, 10.7 to 163.0 hours) was significantly longer than at home (17.6 hours; range, 9.7 to 80.8 hours). Values of all other gastric, small bowel, and large bowel parameters (motility index, motility pattern, pH, and transit time) were similar between phases. No change in gastric pH was detected over the hospitalization period. High interdog variability was evident for all measured parameters. CONCLUSIONS AND CLINICAL RELEVANCE Hospitalization of dogs may result in a prolonged gastric emptying time, which could adversely affect gastric emptying of meals, transit of orally administered drugs, or assessments of underlying motility disorders.

Evaluation of pulmonary hypertension and clinical status in dogs with heartworm by Right Pulmonary Artery Distensibility Index and other echocardiographic parameters

BackgroundPulmonary hypertension (PH) is a frequent and severe phenomenon in heartworm disease caused by Dirofilaria immitis, mainly caused by intimal proliferation of the arteries and pulmonary thromboembolisms. Transthoracic echocardiography is the method of choice for diagnosing PH in dogs although the diagnosis is often based on indirect and subjective parameters. The Right Pulmonary Artery Distensibility Index (RPAD Index) is a method that has been recently validated to estimate the presence and severity of PH in heartworm-infected dogs. This study compared some echocardiographic parameters commonly used to estimate PH in 93 dogs infected by D. immitis and evaluated the impact of the parasite burden, microfilaremia, sex or origin of the dog (client-owned/shelter).ResultsNone of the studied echocardiographic variables seemed useful in the estimation of the evaluated clinical aspects, except for the PA/Ao ratio for parasite burden. The RPAD Index was determined in 88 of the dogs; of these, 70.4% had PH (mild: 37.5%, moderate: 19.3%, severe: 13.6%). This Index showed non-significant differences according to microfilaremia, sex, origin or parasite burden. Symptomatic dogs showed PH more often and displayed more severe PH, in addition the presence of symptoms was greater among dogs with high burden; on the other hand 64.4% of asymptomatic dogs had some degree of PH according to the RPAD Index. Apart from the PA/Ao ratio, the other evaluated echocardiographic variables were not useful in evaluating of the hypertensive status of the heartworm-infected dog compared to the RPAD Index.ConclusionsThe estimation of most common indirect parameters is not useful in predicting PH in heartworm-infected dogs. The results confirm the RPAD Index as an objective and supportive test in the monitoring and evaluation of PH in the heartworm-infected dog, and show a potential diagnostic value for the detection of PH in asymptomatic animals.

Repeated Famotidine Administration Results in a Diminished Effect on Intragastric pH in Dogs

BackgroundFamotidine is an acid suppressant commonly administered to dogs. Prolonged famotidine use in people results in decreased efficacy, but the effect in dogs is unknown.Hypothesis/ObjectivesTo compare the effect of repeated oral administration of famotidine or placebo on intragastric pH and serum gastrin in dogs. We hypothesized that famotidine would have a diminished effect on intragastric pH on day 13 compared to day 1.AnimalsSix healthy adult colony Beagles.MethodsRandomized, 2‐factor repeated‐measures crossover design. All dogs received oral placebo or 1.0 mg/kg famotidine q12h for 14 consecutive days. Intragastric pH monitoring was used to continuously record intragastric pH on treatment days 1–2 and 12–13. Mean pH as well as mean percentage time (MPT) that intragastric pH was ≥3 or ≥4 were compared between and within groups by analysis of variance. Serum gastrin was measured on days 0, 3, and 12 for each treatment.ResultsContinued administration of famotidine resulted in a significant decrease in mean pH, MPT ≥3, and MPT ≥4 (P < .0001) on day 12 and 13. This resulted in a mean decrease in pH by 1.63 on days 12 and 13 compared to days 1 and 2. Furthermore, a mean decrease of MPT ≥3 and MPT ≥4 by 33 and 45% was observed for the same time period, respectively.Conclusions and Clinical ImportanceContinued administration of famotidine results in a diminished effect on intragastric pH in dogs. Caution is advised when recommending long‐term, daily oral administration of famotidine to dogs.

Which is More Effective in Altering the Intra-Gastric pH in Dogs, Omeprazole or Ranitidine?

Clinical bottom line&#x0D; Based on the current available evidence, omeprazole is the superior choice for raising intra-gastric pH.&#x0D;

Quantitative accuracy of the simplified strong ion equation to predict serum pH in dogs.

BackgroundElectrochemical approach to the assessment of acid‐base states should provide a better mechanistic explanation of the metabolic component than methods that consider only pH and carbon dioxide.Hypothesis/ObjectivesSimplified strong ion equation (SSIE), using published dog‐specific values, would predict the measured serum pH of diseased dogs.AnimalsTen dogs, hospitalized for various reasons.MethodsProspective study of a convenience sample of a consecutive series of dogs admitted to the Massey University Veterinary Teaching Hospital (MUVTH), from which serum biochemistry and blood gas analyses were performed at the same time. Serum pH was calculated (Hcal+) using the SSIE, and published values for the concentration and dissociation constant for the nonvolatile weak acids (Atot and K a), and subsequently Hcal+ was compared with the dog's actual pH (Hmeasured+). To determine the source of discordance between Hcal+ and Hmeasured+, the calculations were repeated using a series of substituted values for Atot and K a.ResultsThe Hcal+ did not approximate the Hmeasured+ for any dog (P = 0.499, r 2 = 0.068), and was consistently more basic. Substituted values Atot and K a did not significantly improve the accuracy (r 2 = 0.169 to <0.001). Substituting the effective SID (Atot−[HCO3−]) produced a strong association between Hcal+ and Hmeasured+ (r 2 = 0.977).Conclusions and clinical importanceUsing the simplified strong ion equation and the published values for Atot and K a does not appear to provide a quantitative explanation for the acid‐base status of dogs. Efficacy of substituting the effective SID in the simplified strong ion equation suggests the error lies in calculating the SID.

Efficacy of intravenous administration of combined acid suppressants in healthy dogs.

BackgroundShort‐term intravenous co‐administration of famotidine and pantoprazole is used by some veterinarians to treat gastrointestinal bleeding in critically ill dogs. However, clinical studies have not evaluated the efficacy of combination acid suppressant treatment in dogs.Hypothesis/ObjectivesTo compare the effect of intravenous co‐administration of famotidine and pantoprazole to monotherapy with pantoprazole on intragastric pH in dogs. We hypothesized that single agent pantoprazole would be more effective than combination with famotidine.AnimalsTwelve healthy adult colony dogs.MethodsRandomized, 2‐way crossover design. All dogs received placebo (0.9% saline) for 24 hours followed by 1.0 mg/kg IV q12h pantoprazole or combination treatment with famotidine and pantoprazole for 3 consecutive days. Intragastric pH monitoring was used to continuously record intragastric pH for 96 hours beginning on day 0 of treatment. Mean percentage time (MPT) that intragastric pH was ≥3 and ≥4 were compared between groups using ANOVA with a posthoc Tukey‐Kramer test (α = 0.017).ResultsThe MPT ± standard deviation intragastric pH was greater than ≥3 and 4 were 79 ± 17% and 68 ± 17% for pantoprazole and 74 ± 19% and 64 ± 23% for combination treatment, respectively. There were no significant differences in MPT intragastric pH was ≥3 and 4 between groups. Pantoprazole administered alone achieved pH goals established for humans with acid‐related disorders.Conclusions and Clinical ImportanceThese results suggest that short‐term combination treatment with famotidine and pantoprazole is not superior to pantoprazole alone for increasing intragastric pH in dogs.

Effect of prolonged general anesthesia with sevoflurane and laparoscopic surgery on gastric and small bowel propulsive motility and pH in dogs

ObjectiveTo determine if general anesthesia with sevoflurane and laparoscopic surgery changed gastric and small bowel propulsive motility or pH in dogs. Study designProspective, controlled trial. AnimalsTwelve, 19–24 months old, female, Treeing Walker Hound dogs, weighing 23–30 kg. MethodsDogs were anesthetized for a median of 8.5 hours during another study to determine the minimum alveolar concentration of sevoflurane using a visceral stimulus. Gastric and small bowel motility were determined using a sensor capsule that measures pressure, pH and temperature. Gastric transit time and motility index were calculated. For 8/12 dogs, gastric motility, pH and transit time were measured. In 4/12 dogs, small bowel motility and pH were measured. ResultsAnesthesia decreased gastric and small bowel motility but did not change luminal pH. Mean gastric contraction force decreased from median (range) 11 (8–20) to 3 (1–10) mmHg (p < 0.01) and gastric motility index decreased from 0.63 (0–1.58) to 0 (0–0.31; p = 0.01). Frequency of contractions did not change, 3.7 (1.6–4.4) versus 2.8 (0.1–5.1) contractions minute−1 (p = 0.1). Gastric motility returned to normal 12–15 hours following anesthesia. Gastric emptying was prolonged from 12 (5.3–16) to 49 (9.75–56.25) hours (p < 0.01). Mean small bowel contraction force decreased from 34 (24–37) to 3 (0.9–17) mmHg (p < 0.02) and motility index decreased from 3.75 (1–4.56) to 0 (0–1.53; p = 0.02). Frequency of contractions did not change, 0.5 (0.3–1.4) versus 1.4 (0.3–4.6) contractions minute−1 (p = 0.11). Small bowel motility returned within 2 hours after anesthesia. Laparoscopy did not result in changes to gastric or small bowel parameters beyond those produced by general anesthesia. Conclusions and clinical relevanceThe force of gastric and small bowel contractions decreased during sevoflurane anesthesia for laparoscopy. Although gastric motility returned to normal within 12–15 hours the impairment of gastric emptying lasted 30–40 hours, predisposing dogs to postoperative ileus.

SUPPLEMENTATION OF FRUCTOOLIGOSACCHARIDES (FOS) ON FAECAL CHARACTERISTICS OF ADULT DOGS

Foram avaliadas as características das fezes de cães alimentados com três níveis de inclusão de FOS (0.000; 0.047 e 0.095%) na dieta. Foram utilizados 15 cães adultos da raça Beagle. O experimento seguiu um delineamento inteiramente casualizado, com cinco dias de colheita de dados e cinco cães recebendo cada tratamento, totalizando 25 observações por tratamento. As dietas foram oferecidas para os cães por um período de adaptação de 25 dias seguidos de cinco dias de colheita total de fezes. As médias foram comparadas pelo teste de Tukey. Os cães alimentados com a dieta sem inclusão de FOS apresentaram fezes com menor teor de matéria seca e menor escore em relação aos animais que receberam 0.047 ou 0.095% de FOS na ração, os quais não diferiram entre si. O pH fecal de cães suplementados com 0.095% de FOS foi menor do que o dos cães que receberam 0.047 ou 0.000% de FOS. O teor de amônia faecal e a quantidade de fezes excretadas não diferiram entre os tratamentos. A suplementação com 0.095% de FOS na dieta melhora a qualidade das fezes dos cães.