# Veterinary Emergency Drug Formulary: Quick Reference ## Key Takeaways - The RECOVER Initiative's evidence-based guidelines form the primary framework for veterinary CPR, emphasizing basic and advanced life support, with drug administration integrated into the advanced phase without interrupting chest compressions. - Epinephrine is the first-line vasopressor in cardiac arrest due to its alpha-mediated vasoconstriction, crucial for redirecting blood flow to the brain and myocardium, with dose selection dictated by arrest rhythm and duration. - Balanced isotonic crystalloids are the default fluid resuscitation choice, with rates guided by perfusion parameters and serial reassessment, while colloids and hypertonic saline are reserved for specific indications. - Monitoring during emergency drug administration prioritizes continuous electrocardiography, blood pressure, and capnography where available, with end-tidal CO2 below 10 mmHg indicating poor perfusion and a rise above 30 mmHg signaling return of spontaneous circulation. - Species-specific differences are critical, particularly in cats, which are more sensitive to catecholamine arrhythmogenic effects and require lower epinephrine doses, and dogs, which tolerate higher lidocaine doses for ventricular arrhythmias. - Contraindication checks for species, suspected toxins, pre-existing cardiac disease, and current drug history are mandatory before administering any emergency drug to mitigate adverse events. --- This reference organizes the essential drugs used in veterinary emergency and critical care across dogs, cats, and common large animal species. It serves the practicing veterinarian who needs a structured overview of drug classes, indications, contraindications, and monitoring priorities during resuscitation and acute stabilization. The article answers the clinical question of which drugs belong in a crash cart, why each is selected, and what parameters guide their safe use. Doses are deliberately omitted. Current formulary and label references must be consulted for every drug before administration, because dose ranges vary by species, route, and clinical context. The focus here is decision logic: when to reach for a drug, when to avoid it, and what to watch while it works. ## At a Glance | Parameter | Decision or Fact | |---|---| | Primary resuscitation framework | RECOVER Initiative evidence-evaluated consensus guidelines for CPR in dogs and cats | | First-line vasopressor in cardiac arrest | Epinephrine, with dose selection based on arrest rhythm and duration | | Anticholinergic for bradycardia | Atropine, reserved for vagally mediated or symptomatic bradyarrhythmias | | Reversal agent for opioid depression | Naloxone, titrated to effect instead of given as a fixed bolus | | Glucose emergency | Dextrose, with blood glucose confirmation before administration whenever feasible | | Antiarrhythmic for ventricular tachycardia | Lidocaine in dogs, amiodarone as an alternative, species differences are critical | | Fluid resuscitation default | Balanced isotonic crystalloids, with rate guided by perfusion parameters and serial reassessment | | Monitoring priority during drug administration | Continuous electrocardiography, blood pressure, and capnography where available | | Contraindication check before any emergency drug | Confirm species, suspected toxin, pre-existing cardiac disease, and current drug history | ## Physiology of the Emergency Drug Response Emergency drugs act on a limited set of receptor systems that govern perfusion, rhythm, and oxygen delivery. The adrenergic system dominates resuscitation pharmacology. Alpha-1 receptor activation produces vasoconstriction and afterload elevation. Beta-1 activation increases chronotropy and inotropy. Beta-2 activation causes bronchodilation and vasodilation. The balance of these effects determines whether a given catecholamine raises blood pressure, accelerates the heart, or both. The cholinergic system provides the counterweight. Vagal tone slows the sinoatrial and atrioventricular nodes through muscarinic receptor activation. Anticholinergic drugs block this brake and are useful when bradycardia threatens perfusion. Calcium handling underpins both contraction and electrical stability, which explains why calcium channel blockers and calcium supplements occupy opposite ends of the emergency drug spectrum. Oxygen delivery depends on hemoglobin saturation, cardiac output, and tissue extraction. Emergency drugs that improve cardiac output do not help if hypoxemia or severe anemia limits oxygen content. This physiological hierarchy explains why airway management and ventilation precede drug administration in the RECOVER CPR algorithm. Drugs cannot compensate for a failed airway. ## The RECOVER Framework The RECOVER Initiative publishes evidence-evaluated consensus guidelines for cardiopulmonary resuscitation in dogs and cats. These guidelines organize resuscitation into basic life support, advanced life support, and post-arrest care. The drug formulary for cardiac arrest operates within the advanced life support phase. Vasopressors are the pharmacological core of advanced life support. Epinephrine remains the first-line agent because its alpha-mediated vasoconstriction redirects cardiac output to the brain and myocardium during chest compressions. Vasopressin is an alternative or adjunct in some protocols. Atropine is not recommended for routine asystole or pulseless electrical activity, because vagal blockade does not address the underlying mechanism of these rhythms. The RECOVER guidelines emphasize that drug administration must not interrupt chest compressions. Vascular access, whether intravenous or intraosseous, should be obtained without pausing compressions. Endotracheal drug administration is a second-line route with unpredictable absorption and is used only when vascular access is impossible. The guidelines also address post-arrest care, where antiarrhythmics, inotropes, and vasopressors may be needed to maintain perfusion while the myocardium recovers. ## Adrenergic Agents and Their Selection Epinephrine is the foundational vasopressor in cardiac arrest. Its alpha effects raise diastolic blood pressure, which drives coronary perfusion during the relaxation phase of compressions. Its beta effects increase myocardial oxygen demand, a trade-off that becomes relevant in prolonged resuscitation. The RECOVER guidelines address dose selection based on arrest rhythm and duration, and current references must be consulted for specific protocols. Norepinephrine provides potent alpha-mediated vasoconstriction with less chronotropic effect than epinephrine. It is used in post-arrest hypotension and distributive shock when perfusion pressure is inadequate despite fluid resuscitation. Dobutamine is a synthetic catecholamine with predominant beta-1 activity, making it useful for myocardial depression and low cardiac output states with adequate blood pressure. Dopamine occupies an intermediate position, with dose-dependent effects that shift from dopaminergic to beta-adrenergic to alpha-adrenergic as the infusion rate increases. The selection among these agents depends on the hemodynamic profile. A patient with hypotension and normal heart rate may benefit from norepinephrine. A patient with hypotension and bradycardia may need epinephrine or dopamine. A patient with adequate pressure but poor perfusion and pulmonary edema may benefit from dobutamine. Serial blood pressure and perfusion assessment guides these choices, and the MSD Veterinary Manual provides species-specific guidance on catecholamine selection and monitoring. ## Anticholinergics and Chronotropic Support Atropine blocks muscarinic receptors and removes vagal inhibition of the sinoatrial and atrioventricular nodes. It is indicated for symptomatic bradycardia, particularly when caused by high vagal tone from gastrointestinal disease, ocular manipulation, or certain toxins. It is not indicated for bradycardia caused by hypothermia, severe hyperkalemia, or advanced heart block, where the mechanism lies outside vagal control. Glycopyrrolate is an alternative anticholinergic with a slower onset and longer duration than atropine. It does not cross the blood-brain barrier and causes less central nervous system stimulation. The choice between the two often depends on availability and the desired duration of effect. Both drugs can precipitate tachyarrhythmias, and their use in patients with pre-existing supraventricular tachycardia requires caution. Monitoring during anticholinergic administration includes heart rate, rhythm, and blood pressure. Excessive dosing produces persistent tachycardia, which increases myocardial oxygen demand and can worsen ischemia in patients with coronary disease. The effect should be titrated to the lowest dose that restores adequate perfusion. ## Fluids and Metabolic Emergencies Fluid therapy is the first intervention for hypovolemic shock, and the AAHA and AAFP fluid therapy guidelines for dogs and cats provide consensus recommendations on fluid selection, rate planning, and monitoring. Balanced isotonic crystalloids are the default resuscitation fluid. Colloids, hypertonic saline, and blood products are reserved for specific indications where crystalloids alone are insufficient or contraindicated. Dextrose is the emergency treatment for hypoglycemia. Blood glucose should be confirmed before administration whenever the patient is stable enough for testing. In a seizing or comatose patient, dextrose may be given empirically after blood sampling, with the sample analyzed retrospectively. Hypertonic dextrose is irritating to veins, and dilution or central venous administration reduces the risk of phlebitis. Calcium is indicated for hypocalcemia causing muscle tremors, seizures, or cardiac arrhythmias. It is contraindicated in hypercalcemia and must be given slowly with electrocardiographic monitoring, because rapid administration can cause bradycardia and cardiac arrest. Calcium gluconate is preferred over calcium chloride in most peripheral venous access situations because it is less irritating to tissues. ## Emergency Drug Administration: Routes, Timing, and Equipment The route of administration in a crashing patient is a clinical decision that changes with vascular access, patient size, and the drug's physicochemical properties. Peripheral venous access is the default for most emergencies, but the cephalic and saphenous veins may be poorly perfused in shock. Intraosseous access provides a reliable alternative when venous access fails, and drug absorption from the medullary cavity reaches central circulation within seconds. The intraosseous route accepts all drugs that can be given intravenously, including vasopressors, calcium, and sodium bicarbonate. Endotracheal administration is a salvage option for lipid-soluble drugs only. Epinephrine, atropine, lidocaine, and naloxone can be given via the endotracheal tube at two to two and a half times the intravenous dose, diluted in sterile water or saline to a total volume of 5 to 10 mL in dogs and 2 to 5 mL in cats. The drug is instilled through a catheter passed beyond the tube tip, followed by several rapid ventilations. Drugs that are not lipid soluble, including calcium salts, sodium bicarbonate, and most crystalloids, will not absorb across the alveolar membrane and must never be given by this route. The RECOVER guidelines specify that drug administration should not interrupt chest compressions for more than ten seconds. [RECOVER Initiative Veterinary CPR Guidelines](https://recoverinitiative.org/) recommend that all drugs be drawn up before arrest whenever possible, with the crash cart organized so that the most frequently used agents are immediately accessible. In a witnessed arrest, the priority is defibrillation where available, followed by drug therapy. In an unwitnessed arrest, the priority is two minutes of CPR before drug administration. ### Vascular Access Decision Points | Access Type | Time to Establish | Best Use | Limitations | |---|---|---|---| | Peripheral venous catheter | 30 to 90 seconds | First-line access in most patients | Collapses in severe hypovolemia, dislodges during compressions | | Intraosseous catheter | 60 to 120 seconds | Cardiac arrest, severe shock, pediatric or neonatal patients | Requires special needle, risk of osteomyelitis if left in place | | Central venous catheter | 3 to 10 minutes | Post-arrest care, continuous vasopressor infusion, repeated blood sampling | Requires ultrasound or landmarks, pneumothorax risk in cats | | Endotracheal | Immediate | Lipid-soluble drugs only, when no vascular access exists | Unreliable absorption, cannot deliver fluids or calcium | The choice of access changes with species. Cats have small peripheral veins that collapse rapidly in hypovolemia, so intraosseous access in the proximal femur or humerus is often the fastest reliable option. In dogs, the lateral saphenous vein is usually accessible even in moderate shock. In production animals, the jugular vein is the standard emergency route, but the auricular vein in cattle and the cephalic vein in small ruminants may be used for bolus drugs. The intraosseous route is rarely practical in adult cattle because of the thick cortex and the volume of drug required. ## Monitoring Parameters During Emergency Drug Therapy Monitoring during resuscitation serves two purposes: detecting return of spontaneous circulation and detecting drug toxicity. The electrocardiogram alone is insufficient, because electrical activity can persist without perfusion. Capnography provides the most reliable non-invasive indicator of cardiac output during CPR. End-tidal carbon dioxide below 10 mmHg during compressions indicates poor perfusion and should prompt a change in compression technique or a search for correctable causes. A sudden rise in end-tidal carbon dioxide to 30 mmHg or above is an early indicator of return of spontaneous circulation. [RECOVER Initiative Veterinary CPR Guidelines](https://recoverinitiative.org/) recommend continuous capnography during all resuscitation attempts where equipment is available. Blood pressure monitoring becomes meaningful after return of spontaneous circulation. A mean arterial pressure below 60 mmHg indicates inadequate organ perfusion and justifies continued vasopressor support. In the post-arrest period, serial lactate measurements track the resolution of tissue hypoxia. A rising lactate despite apparent hemodynamic stability suggests ongoing hypoperfusion, ongoing seizure activity, or limb ischemia from a peripheral arterial catheter. Pulse oximetry is unreliable during cardiac arrest because of poor peripheral pulsation, but it regains utility after return of spontaneous circulation. Oxygen saturation below 94 percent on room air warrants supplemental oxygen. In cats, pulse oximetry readings are frequently artefactual during vasoconstriction, and the clinician should confirm readings against mucous membrane color and arterial blood gas analysis where available. ### Drug-Specific Monitoring | Drug Class | Monitor | What It Detects | Action Threshold | |---|---|---|---| | Adrenergic agonists | Heart rate, rhythm, blood pressure | Tachyarrhythmia, hypertension | Withhold or reduce infusion if ventricular arrhythmia develops | | Anticholinergics | Heart rate, pupil size, gastrointestinal auscultation | Inadequate vagolytic effect, ileus | Repeat dose if heart rate does not rise within 2 minutes | | Calcium salts | ECG, heart rate | Bradycardia, shortened QT interval | Stop infusion if bradycardia or arrhythmia appears | | Sodium bicarbonate | Blood gas, ionised calcium, potassium | Metabolic alkalosis, hypocalcemia | Recheck blood gas within 15 minutes of administration | | Opioid antagonists | Respiratory rate, mentation, pain score | Re-narcotisation, withdrawal | Redose if respiratory depression recurs | ## The Emergency Drug Chart as a Working Document The emergency drug chart is a clinical tool, not a static poster. It should list each drug, its concentration, the calculated dose for the patient's body weight, the route, and the expected onset of effect. The chart must be updated when drug concentrations change between suppliers, because a 1:1,000 epinephrine solution and a 1:10,000 solution are not interchangeable. The chart should also record the time of each drug administration, the dose given, and the patient's response, because this information drives the next decision. A common failure mode is the administration of a second dose of a drug that has not had time to work. Epinephrine given intravenously reaches peak effect within one to two minutes. Atropine reaches peak effect within two to three minutes. If the clinician re-administers a drug before its peak effect, the second dose stacks on the first and can produce toxicity. The chart should therefore include the expected onset time for each drug, and the resuscitation team should announce the time of each dose aloud. Documentation after the event should record the sequence of drugs, the doses, the routes, the monitoring parameters at each two-minute interval, and the time of return of spontaneous circulation or death. This record serves both medical and legal purposes. The [American Veterinary Medical Association practice resources](https://www.avma.org/resources-tools) note that contemporaneous medical records are the foundation of professional accountability, and the resuscitation record is no exception. ## Species-Specific Adjustments in Emergency Drug Use Cats present the most significant species differences in emergency drug response. Feline myocardium is more sensitive to the arrhythmogenic effects of catecholamines, and the recommended dose of epinephrine in cats is lower than in dogs on a milligram per kilogram basis. Cats also have a higher vagal tone, so atropine may produce a more pronounced and more prolonged chronotropic response. The [MSD Veterinary Manual](https://www.msdvetmanual.com/) advises caution with repeated atropine dosing in cats because of the risk of supraventricular tachycardia. Dogs tolerate higher doses of lidocaine and are the species in which lidocaine is most commonly used for ventricular arrhythmias. Cats are exquisitely sensitive to lidocaine toxicity, with seizures and cardiac depression occurring at doses that are safe in dogs. When lidocaine is required in a cat, the dose must be reduced and the infusion rate must be calculated carefully. Ruminants present a different set of challenges. The rumen creates a large reservoir of fluid that can dilute drugs given orally, but emergency drugs are almost always given parenterally. Ruminants are prone to vagal bradycardia during recumbency and manipulation, and atropine is frequently required. However, atropine reduces rumen motility and can precipitate bloat in cattle, so the smallest effective dose should be used. The [WOAH terrestrial animal health standards](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) address emergency drug use in production animals primarily through the lens of withdrawal periods and food safety, and the clinician must consult current regional withdrawal information before treating any food animal. ## Fluid Selection in the Emergency Patient Fluid therapy in the emergency patient is not a single protocol but a sequence of decisions based on the suspected pathophysiology. The [AAHA/AAFP fluid therapy guidelines](https://www.aaha.org/resources/2024-aaha-fluid-therapy-guidelines-for-dogs-and-cats/) distinguish between resuscitation, rehydration, and maintenance phases, and the drug formulary must be read alongside these phases. Isotonic crystalloids remain the first-line resuscitation fluid for most hypovolemic patients. Balanced electrolyte solutions such as lactated Ringer's solution are preferred over 0.9 percent saline in most cases because they avoid hyperchloraemic metabolic acidosis. Hypertonic saline at 7.2 to 7.5 percent is an option for rapid small-volume resuscitation in dogs and cattle, particularly when the patient has concurrent head trauma and cerebral edema. Hypertonic saline draws fluid from the interstitial space into the vasculature, so it must be followed by isotonic crystalloids to replace the interstitial deficit. Colloids are no longer recommended as first-line resuscitation fluids in small animals. The 2024 AAHA/AAFP guidelines advise against synthetic colloids in most emergency patients because of the risk of coagulopathy and acute kidney injury. [AAHA/AAFP fluid therapy guidelines](https://www.aaha.org/resources/2024-aaha-fluid-therapy-guidelines-for-dogs-and-cats/) reserve colloids for specific indications such as hypoalbuminaemia with ongoing loss, and even then the evidence base is limited. The fluid rate must be reassessed at least every 15 minutes during active resuscitation. A patient that remains hypotensive after two boluses of crystalloid may require vasopressor support instead of additional fluid. The decision to switch from fluid to vasopressor is guided by the patient's response to the first bolus, the presence of pulmonary edema, and the suspected underlying cause. In cardiogenic shock, fluids are contraindicated and vasopressor support is the priority. In hemorrhagic shock, fluids are temporising and the priority is hemorrhage control. ## Recognized Complications and Early Detection Emergency drug therapy fails most often through preventable complications instead of drug inefficacy. Hypoperfusion, arrhythmia, and metabolic derangement dominate the list, and each has a detectable prodrome. Vasopressor extravasation produces local tissue necrosis that may not be visible for hours. Detect early by inspecting the catheter site at least hourly, noting perivascular swelling, skin pallor, or pain on palpation. Central venous administration reduces but does not eliminate this risk. Rebound hypotension follows abrupt discontinuation of vasopressor infusions. Wean infusions by 10 to 20 percent decrements instead of stopping at a target blood pressure. Serial blood pressure measurement every 5 to 10 minutes during weaning identifies the patient who requires a slower taper. Tachyarrhythmia from adrenergic excess presents as worsening tachycardia despite adequate perfusion, ventricular premature complexes, or supraventricular tachycardia on the electrocardiogram. The [RECOVER veterinary CPR guidelines](https://recoverinitiative.org/) specify when antiarrhythmic therapy is indicated during and after resuscitation, and they emphasize that hypothermia, acidosis, and electrolyte derangement must be corrected before antiarrhythmics will be effective. Hyperlactatemia that fails to clear after fluid resuscitation signals ongoing hypoperfusion or a missed surgical lesion. Serial lactate measurement at 2 and 6 hours after resuscitation separates patients who are responding from those who need further diagnostic imaging or surgical exploration. ## Common Errors and Corrective Actions Less experienced clinicians frequently confuse the indications for atropine and glycopyrrolate. Atropine is preferred for asystole and severe bradyarrhythmia because of its faster onset. Glycopyrrolate causes less tachycardia but acts more slowly. Using glycopyrrolate in a bradycardic arrest patient delays chronotropic support. Dosing errors arise from concentration confusion. Emergency drugs are stocked in multiple concentrations, and a 1 mg/mL vial of epinephrine is not interchangeable with a 0.1 mg/mL preparation. Verify the concentration on the vial before drawing the dose, and have a second person confirm the calculation for high-alert drugs. Fluid overload is the most common iatrogenic complication in emergency fluid therapy. The [AAHA and AAFP fluid therapy guidelines](https://www.aaha.org/resources/2024-aaha-fluid-therapy-guidelines-for-dogs-and-cats/) recommend serial body weight, respiratory rate, and lung auscultation as the minimum monitoring set. Weight gain exceeding 2 percent over 12 hours warrants reducing the fluid rate. Vasopressor administration through a peripheral catheter without verifying placement causes silent extravasation. Flush the catheter with saline and observe for swelling before connecting the infusion. Use a dedicated lumen for vasopressors when a central line is present. ## Limitations of Current Evidence The evidence base for emergency drug therapy in veterinary patients is thin. Most recommendations derive from human medicine, small animal case series, or expert opinion. The RECOVER guidelines explicitly grade the quality of evidence behind each recommendation, and many receive a low or very low evidence rating. Clinicians should recognize that a guideline recommendation is not equivalent to a proven treatment effect. Expert opinion still differs on several points. The choice between high-dose and low-dose epinephrine in asystolic arrest remains contested. The role of vasopressin in veterinary resuscitation is unresolved. Whether routine bicarbonate administration benefits any veterinary arrest patient is debated, with most experts reserving it for prolonged arrest with confirmed severe acidaemia. Species differences compound the uncertainty. Feline patients metabolise many drugs differently from dogs, and the evidence for feline-specific dosing is sparse. Exotic species, including rabbits, birds, and reptiles, have almost no pharmacokinetic data for emergency drugs. The [MSD Veterinary Manual](https://www.msdvetmanual.com/) provides species-specific guidance where it exists, but clinicians must extrapolate cautiously. ## Escalation and Reporting Referral to a specialist is warranted when a patient requires mechanical ventilation, continuous vasopressor infusion beyond 24 hours, renal replacement therapy, or advanced arrhythmia management. Early referral is preferable to rescue referral. A patient who has required two or more vasopressors, who remains hypotensive after 60 minutes of fluid resuscitation, or who develops refractory ventricular arrhythmia should be transferred before decompensation becomes irreversible. Laboratory involvement is indicated for serial blood gas analysis, lactate monitoring, electrolyte measurement, and coagulation testing. Point-of-care devices are useful for screening, but abnormal values that guide major therapeutic decisions should be confirmed by a reference laboratory when the clinical picture does not match the point-of-care result. Regulatory reporting obligations vary by jurisdiction. Suspected adverse drug reactions, particularly those involving products with a known reporting requirement, should be reported through the appropriate national system. The [AVMA practice resources](https://www.avma.org/resources-tools) describe the reporting expectations for veterinarians in the United States. Reportable events include unexpected deaths, suspected product defects, and adverse reactions to extralabel drug use. For food animals, withdrawal times and residue avoidance are mandatory considerations. The [WOAH terrestrial animal health standards](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) address the responsible use of antimicrobials and the prevention of residues in animals destined for human consumption. Emergency drug selection in production animals must account for these requirements before administration, not after. ## Troubleshooting Table | Observation | Likely Cause | Discriminating Check | | --- | --- | --- | | Blood pressure falls despite increasing vasopressor dose | Hypovolemia, acidosis, or sepsis | Central venous pressure, lactate, blood gas | | Tachycardia persists after atropine | Anticholinergic excess or hypovolemia | Compare heart rate to fluid status, check for dry mucous membranes | | No electrocardiographic change after epinephrine | Wrong concentration or expired drug | Verify vial concentration, check expiry date | | Patient remains bradycardic after glycopyrrolate | Drug too slow in onset or vagal tone too high | Reassess in 5 minutes, consider atropine | | Catheter site swelling during vasopressor infusion | Extravasation | Stop infusion, aspirate catheter, inspect site | | Lactate rises despite fluid therapy | Ongoing ischemia or sepsis | Repeat lactate in 2 hours, consider imaging or surgery | | Ventricular arrhythmia after defibrillation | Reperfusion injury or electrolyte imbalance | Measure potassium and magnesium, check acid-base status | ## Frequently Asked Questions ### How do I manage emergency drug administration when intravenous access is impossible? When IV access fails, select the route by drug and patient stability. Intraosseous cannulation provides rapid access to the central circulation and accepts most drugs given IV, including vasopressors and sodium bicarbonate. Endotracheal administration is a rescue option for lipid-soluble drugs such as epinephrine, atropine, and lidocaine, but absorption is erratic and doses must be increased. Intranasal and intramuscular routes work for some analgesics and benzodiazepines but have slower onset. For hypovolemic patients, the [AAHA/AAFP fluid therapy guidelines](https://www.aaha.org/resources/2024-aaha-fluid-therapy-guidelines-for-dogs-and-cats/) describe vascular access decision points that prioritize catheter site selection and confirm placement before giving vasoactive drugs. If a peripheral catheter cannot be placed, consider a cutdown or jugular catheter instead of delaying treatment. ### What emergency drugs should I stock when working with limited budget or remote practice? Prioritize drugs that reverse immediately life-threatening conditions: epinephrine, atropine, naloxone, dextrose, and a benzodiazepine. Add calcium gluconate, sodium bicarbonate, and an antihistamine where toxic exposures are common. Vasopressin and amiodarone are useful but can be deferred if budget is tight. Store drugs with short shelf lives, such as epinephrine, with rotation dates visible on the crash cart. The [MSD Veterinary Manual](https://www.msdvetmanual.com/) provides species-specific indications that help justify stocking choices for mixed or production animal practice. For remote settings, carry multidose vials where contamination risk is manageable and verify that cold-chain requirements are met. Reassess the inventory quarterly against local case mix and expiry dates. ### How does emergency drug selection differ in exotic or production animal patients? Drug selection shifts with species physiology and legal constraints. Ruminants require careful dosing of alpha-2 agonists because of their sensitivity to respiratory depression, and calcium solutions must be given slowly with cardiac monitoring. Horses tolerate large fluid volumes but are prone to laminitis with excessive catecholamine exposure. Exotic species often need weight-based dose extrapolation from domestic carnivores, which carries real risk of toxicity. For food animals, drug choice affects milk and meat withdrawal periods, and some drugs are prohibited entirely. The [WOAH terrestrial animal health standards](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/) address disease control and treatment reporting obligations that may override routine clinical choices in reportable conditions. Always confirm species-specific contraindications before administration. ### What should I record after an emergency drug event? Document the time of each drug administration, dose, route, and the patient's response within five minutes of the dose. Record heart rate, rhythm, blood pressure, and respiratory effort before and after intervention. Note any adverse reactions, including arrhythmias or hypotension, and the corrective action taken. Include the person who administered each drug and the batch number for controlled substances. The [AVMA practice resources](https://www.avma.org/resources-tools) outline record-keeping expectations for veterinary practices, including controlled drug logs and medical record completeness. In a cardiac arrest, use a standard resuscitation flow sheet so that epinephrine dosing intervals and defibrillation attempts are traceable. Review the record during the post-arrest debrief to identify delays or dosing errors. ### How do I explain an unexpected death or treatment failure to a client? Lead with the sequence of events, not the drug list. State what happened, what was done, and the time course in plain language. Acknowledge uncertainty directly, for example that the arrhythmia was refractory to the drugs given. Avoid defensive phrasing and do not speculate about causes without evidence. Offer a written summary of the resuscitation record if the client requests it. The [RECOVER Initiative](https://recoverinitiative.org/) guidelines include post-arrest review processes that can help you identify system factors, such as delayed drug delivery, that contributed to the outcome. Frame the conversation around what was learned and what will change in future cases. If a drug error occurred, disclose it honestly and explain the corrective steps taken. ### When should I stop resuscitation efforts in a cardiac arrest patient? Resuscitation should continue until the patient achieves return of spontaneous circulation or the team determines that further efforts are futile. Prolonged asystole beyond 20 minutes with no reversible cause, refractory ventricular fibrillation after multiple defibrillation attempts, and severe pre-existing disease all support stopping. The [RECOVER Initiative](https://recoverinitiative.org/) guidelines provide evidence-evaluated recommendations on termination of resuscitation in dogs and cats, noting that no single variable reliably predicts outcome. Consider the owner's wishes and the patient's quality of life before arrest. Document the time of cessation and the rationale. In production animals, economic and welfare considerations may shorten the resuscitation window, and local regulations may require specific reporting of euthanasia decisions. ## Related Clinical & Scientific Guides * [Toxicology in Emergency Practice: Common Poisons and Diagnostic Approach](/knowledge/veterinary-medicine/emergency-critical-care/toxicology-emergency-practice-common-poisons-diagnostic-approach) * [Veterinary Cardiopulmonary Resuscitation: Post-Cardiac Arrest Care](/knowledge/veterinary-medicine/emergency-critical-care/veterinary-cardiopulmonary-resuscitation-post-cardiac-arrest-care) * [Fluid Therapy Guidelines for Dogs and Cats: A Practical Update](/knowledge/veterinary-medicine/emergency-critical-care/fluid-therapy-guidelines-dogs-cats-practical-update) ## References and Further Reading - [RECOVER Initiative Veterinary CPR Guidelines](https://recoverinitiative.org/). Veterinary Emergency and Critical Care Society. - [AAHA/AAFP Fluid Therapy Guidelines for Dogs and Cats](https://www.aaha.org/resources/2024-aaha-fluid-therapy-guidelines-for-dogs-and-cats/). AAHA. - [MSD Veterinary Manual, Professional Edition](https://www.msdvetmanual.com/). MSD Veterinary Manual. - [American Veterinary Medical Association Practice Resources](https://www.avma.org/resources-tools). American Veterinary Medical Association. - [WOAH Terrestrial Animal Health Code](https://www.woah.org/en/what-we-do/standards/codes-and-manuals/terrestrial-code-online-access/). WOAH. ## Related Articles - [Veterinary Emergency Drug Dosing: Weight-Based Calculations](/knowledge/veterinary-medicine/emergency-critical-care/veterinary-emergency-drug-dosing-weight-based-calculations) - [Veterinary Crash Cart Organization and Emergency Drug Dosing](/knowledge/veterinary-medicine/emergency-critical-care/veterinary-crash-cart-organization-emergency-drug-dosing) - [Capnography in Veterinary Emergency and Critical Care](/knowledge/veterinary-medicine/emergency-critical-care/capnography-veterinary-emergency-critical-care) - [Veterinary Electrocardiography in Emergency and Critical Care](/knowledge/veterinary-medicine/emergency-critical-care/veterinary-electrocardiography-emergency-critical-care) - [Veterinary Toxicology: Common Toxins and Emergency Management](/knowledge/veterinary-medicine/emergency-critical-care/veterinary-toxicology-common-toxins-emergency-management) > This article is educational professional reference material for veterinary audiences. It is not a substitute for veterinary diagnosis, individual clinical judgment, current product labeling, or applicable regulatory requirements.