Diagnostic tests and surgical interventions can be delicate moments for our patients, especially when they are outside their usual environment and without the company of family or loved ones. This situation can lead to increased nervousness, complicating both the professionals' work and the patient's health status.
At IVeM, we understand this situation, which is why we have Quique Plaza, who is responsible for the anesthesia and analgesia service.
To ensure the well-being of our patients and tailor the procedure to each individual, the chosen anesthetic protocol is based on various factors, such as the patient’s condition, the type of intervention required, and any pre-existing conditions. In this regard, conducting a pre-anesthetic consultation is essential to thoroughly understand each patient who will undergo anesthesia.
At IVeM, we take pride in providing comprehensive care for our patients, and the pre-anesthetic consultation is a fundamental part of our approach. We are committed to delivering the highest quality of veterinary care, ensuring that every patient feels cared for, comfortable, and safe before, during, and after any medical or surgical procedure.
The endocrine system comprises glands such as the pancreas, thyroid, adrenal glands, and reproductive system, which secrete hormones to regulate bodily functions. The hypothalamic-pituitary axis controls this system.
Anesthesia and surgery can affect hormone production, which is generally well tolerated in healthy animals but can be detrimental in cases of endocrine diseases. These conditions alter the body’s response to stress, increasing perianesthetic risk. It’s crucial to identify any pre-existing endocrine diseases before performing procedures and to take appropriate measures to manage hormonal imbalances and ensure the animal's safe.
Diabetes is a disease caused by insufficient insulin production or tissue resistance to insulin action. This can lead to high blood sugar levels, which may be dangerous to health.
In the case of anesthesia in animals with diabetes, there are additional challenges. Perioperative glycemic control is essential to ensure that anesthesia is both safe and successful. High or low blood sugar levels can negatively impact the animal's response to anesthesia and increase the risk of complications.
Before surgery, it is important to carefully evaluate and control the blood sugar levels of diabetic animals. This may involve adjustments in insulin dosage or the administration of oral antidiabetic medications.
In addition, preoperative fluid therapy is often implemented to maintain adequate hydration and prevent hemodynamic instability in the postoperative period. The type and amount of fluids administered may depend on the animal’s condition, surgery duration, and other relevant factors.
Hypothyroidism is a condition caused by a deficiency in thyroid hormone production by the thyroid gland. Symptoms are common in animals affected by this condition.
Due to potentially slower hepatic metabolism, short-acting anesthetics and those with extrahepatic elimination, such as inhaled anesthetics and propofol, are preferred. Additionally, drugs that can be antagonized are recommended.
It is important to note that hypothyroid animals have a tendency toward hypothermia, so measures should be taken to conserve heat and apply active warming from the start of the anesthesia procedure.
Because of a marked tendency toward hypoventilation in these animals, they often benefit from mechanical ventilation during the anesthetic procedure. Careful monitoring during the extubation phase is crucial to avoid hypoxia due to hypoventilation and airway obstruction. Oxygen supplementation, monitoring with a pulse oximeter, and antagonizing sedative drugs when possible are recommended.
Hyperthyroidism is a common disease in middle-aged or older cats, while in dogs, it is uncommon and usually associated with malignant tumors. Hyperthyroid cats often have an accelerated metabolism, leading to weight loss and a neglected appearance. They may also exhibit behavioral changes, such as aggression and excessive vocalization, as well as low tolerance to stress.
Hyperthyroidism has significant effects on the cardiovascular system, including systemic hypertension (high blood pressure) and hypertrophic cardiomyopathy (thickening of the heart muscle). Chronic kidney disease is also commonly found in hyperthyroid cats.
When performing anesthesia on an uncontrolled hyperthyroid patient, there is a higher anesthetic risk. It is important to continue administering antithyroid medications until the day of anesthesia.
One of the priorities during anesthesia in hyperthyroid cats is preventing hypothermia, as they may struggle to maintain body temperature due to their small size and low body fat percentage. Monitoring blood pressure, electrocardiogram, and temperature is recommended during anesthesia.
It is essential to keep the mean arterial pressure above 70 mm Hg to ensure adequate renal and myocardial perfusion in cats with chronic hypertension.
This condition is characterized by insufficient production of hormones, particularly aldosterone and cortisol, by the adrenal cortex.
The clinical signs of Addison's disease can vary from mild and intermittent symptoms, such as vomiting, diarrhea, anorexia, and lethargy, to severe crises involving dehydration, bradycardia, hypotension, and syncope. Blood tests often reveal leukopenia, anemia, hypoglycemia, hyponatremia, and hyperkalemia.
The choice of sedative and anesthetic drugs will depend on the animal’s clinical status and the presence of other concurrent diseases.
During anesthesia, it is crucial to monitor blood pressure and aggressively manage hypotension with fluid therapy, vasopressors, and positive inotropes. Corticosteroid deficiency can reduce the efficacy of these drugs due to its influence on vascular tone regulation and electrolyte balance.
After surgery, it is important to continue corticosteroid administration in the immediate postoperative period. Dosages should be gradually reduced over 2-3 days until maintenance therapy is resumed.
Hyperadrenocorticism is characterized by excessive cortisol secretion into the bloodstream.
The main clinical signs of Cushing’s syndrome in animals include polyuria (increased urine production), polydipsia (increased thirst), polyphagia (increased appetite), muscle loss, fat redistribution (pendulous abdomen), and dermatological issues such as alopecia (hair loss), comedones (blackheads), and thin skin. Systemic hypertension (high blood pressure) and an increased risk of thromboembolism are also common findings.
When performing anesthesia in animals with Cushing’s disease, it is important to consider the specific risk factors of the case, as well as issues associated with hyperadrenocorticism. Stabilizing the animal with medical treatment before any anesthetic procedure is recommended.
Additionally, these animals may have reduced respiratory reserve capacity due to muscle weakness and redistribution of fat deposits in the abdomen, which may require mechanical ventilation during anesthesia. It is important to monitor any sudden changes in oxygen saturation, capnography, and cardiovascular variables (such as tachycardia) that may indicate the onset of pulmonary thromboembolism. Since systemic hypertension is common, blood pressure monitoring during anesthesia is recommended, aiming to maintain it at pre-anesthesia levels.
There are no specific contraindications regarding anesthetic drugs to be used in these cases, though chronically hypertensive animals may experience severe hypotension if vasodilator agents are administered.
