Tucker, an 11-year-old male German shepherd dog, is hospitalized for vomiting and collapse. For the past 6 months, he has received meloxicam treatment for arthritis. Physical examination reveals a painful abdomen, elevated heart rate of 195 bpm (normal, 70-120 bpm), and respiratory rate of 42 breaths/min (normal, 18-34 breaths/min), with fair pulses and injected mucous membranes, a rapid capillary refill time, and a rectal temperature of 103.2F (39.6C; normal, 102F 1F [38.9C]). Systolic blood pressure is 75 mm Hg (normal systolic, 110-160 mm Hg). Serum chemistry profile results indicate moderate hypoglycemia (blood glucose, 60 mg/dL; normal, 70-143 mg/dL), and CBC results show a neutrophil count of 23 103/L (normal, 5.05-16.76 103/L) with 10% bands (normal, 0%-3%) and hematocrit of 26% (normal, 37.3%-61.7%). Abdominal ultrasonography confirms free abdominal fluid, which is sampled by fine-needle aspiration. The glucose concentration in the abdominal fluid is 32 mg/dL; total solids are 4.2 g/dL. Cytology of the aspirate shows marked neutrophilic inflammation; many of the neutrophils are degenerate, with occasional neutrophils containing intracellular bacilli. There is no evidence of masses or a foreign body. Based on patient history and presence of septic peritonitis, the dog is prepared for abdominal surgery to confirm a suspected perforated gastric or duodenal ulcer secondary to NSAID treatment.
Which of the following drugs would be appropriate in the management of this patient?
Based on the information provided, how would you grade the following drugs and why?
Correct ResponseDo Not UseAlthough analgesia is required in this dog, adding another NSAID (ie, carprofen) to current treatment with meloxicam would be contraindicated (NSAIDs should not be combined).1 In addition, GI ulceration secondary to NSAID administration is suspected; if ulceration is confirmed during abdominal surgery, NSAID use will likely be contraindicated for the remainder of this dog’s life.
Correct ResponseSafeAs a pure agonist opioid, hydromorphone is an excellent choice both for initial analgesia and as part of premedication before anesthetic induction. Pure agonist opioids provide good analgesia for invasive procedures with minimal cardiovascular side effects1; they can also reduce the doses of induction agent and inhaled gas needed to achieve the required plane of anesthesia, minimizing the hypotension caused by larger doses of induction and inhaled anesthetic drugs.
Correct ResponseDo Not UseDexamethasone is contraindicated in this dog because of suspected GI ulceration and concurrent administration of the NSAID meloxicam.1
Correct ResponseSafeAntibiotics are essential in managing septic peritonitis. Ampicillin–sulbactam is a good choice as a broad-spectrum antimicrobial for community-acquired infection.1 It could be argued, however, that ampicillin–sulbactam is not an adequate antimicrobial for a patient with abdominal sepsis due to high rate of community-acquired Escherichia coli resistance to first-line antimicrobials.2 Consideration of a combination of antibiotics that initially provides broader coverage, followed by reduced coverage based on culture and susceptibility test results (eg, ampicillin–sulbactam combined with amikacin for a dog in which resistant E coli infection is a potential concern), might be advisable.
Correct ResponseSafePantoprazole is an effective proton pump inhibitor (PPI) that can be administered by injection. Some clinicians suggest that twice-daily administration of PPIs may be most effective.3,4 If ulceration is identified or highly suspected, a PPI could help reduce gastric pH and allow for ulcer healing.
Correct ResponseSafeKetamine is a dissociative anesthetic and should be used with an analgesic for invasive pain procedures.1 When given as a CRI at low doses, it can provide analgesia and usually is used in conjunction with an opioid.1 Of note, ketamine is cardiovascularly sparing and does not cause respiratory depression when administered at lower doses.1 In addition, the drug is often used with a benzodiazepine to provide better induction and reduce muscular rigidity, which can occur secondary to ketamine administration.1 At low doses, ketamine may also provide some immunomodulatory benefits in septic patients.5
Correct ResponseDo Not UseWhen canine patients, such as this dog, are at lower risk for highly resistant infections, imipenem and other antibiotics in the carbapenem line of antibiotics would be contraindicated. This line of antibiotics needs to be reserved only for use when absolutely essential to combat specific highly resistant infections for which other medications (eg, aminoglycosides) might be unavailable or contraindicated (eg, due to azotemia).
Correct ResponseCautionBuprenorphine can be an effective analgesic but, because it is a partial agonist, may be inadequate for patients undergoing major abdominal surgery. In addition, buprenorphine is not easily reversible, requiring high doses of naloxone for reversal1 and potentially placing very critical patients at risk for catastrophic complications. In addition, if buprenorphine is administered before surgery, use of pure agonist opioids before or during surgery may have reduced effect because of buprenorphine’s high affinity for µ opioid receptors.1
Correct ResponseSafeAntiemetic medications can be used to reduce nausea and lower patient risk for postoperative vomiting1 and aspiration pneumonia. Maropitant would be a safe option in this dog.
Correct ResponseCautionAlthough hetastarch can be an effective fluid for volume replacement in hypotensive patients, it may cause adverse effects, including coagulopathy and acute kidney injury.6 In this dog, fluid replacement is essential; however, at least initially, a balanced electrolyte solution is probably more appropriate.
CRI = constant-rate infusion, PPI = proton pump inhibitor
- Plumb DC. Plumbs Veterinary Drug Handbook. 6th ed. Hoboken, NJ: Wiley-Blackwell; 2008.
- Boothe D, Smaha T, Carpenter DM, Shaheen B, Hatchcock T. Antimicrobial resistance and pharmacodynamics of canine and feline pathogenic E. coli in the United States. J Am Anim Hosp Assoc. 2012;48(6):379-389.
- utalo S, Ruetten M, Hartnack S, Reusch CE, Kook PH. The effect of orally administered ranitidine and once-daily or twice-daily orally administered omeprazole on intragastric pH in cats. J Vet Intern Med. 2015;29(3):840-846.
- Bersenas AM, Mathews KA, Allen DG, Conlon PD. Effects of ranitidine, famotidine, pantoprazole, and omeprazole on intragastric pH in dogs. Am J Vet Res. 2005;66(3):425-431.
- Liu FL, Chen TL, Chen RM. Effects of ketamine induced immunosuppression. Acta Anaesthesiol Taiwan. 2012;50(4):172-177.
- U.S. Food & Drug Administration. FDA safety communication: boxed warning on increased mortality and severe renal injury, and additional warning on risk of bleeding, for use of hydroxyethyl starch solutions in some settings. U.S. FDA website. https://www.fda.gov/BiologicsBloodVaccines/SafetyAvailability/ucm358271.htm. Updated November 25, 2013. Accessed February 28, 2017.