I encountered the following problem in an experiment. After intraperitoneal injection of urethane to rats at a dosage of 1.3 g/kg, the rats develop hypotension (100/50 mmHg) and bradycardia (HR~240-260). Gradually, the blood pressure drops (50/20 mmHg) and the HR rises to 450-480, after which the rat goes into asystole. The animal is on an artificial ventilation with the parameters of ventilation with room air 1 ml per 100 g of animal weight and a rate of 60 per min. Also tried other parameters of ventilation, tried to change the dose of anesthetic, but nothing helps. Please help, what could be the problem.
Valery Sevrukevitch Hypothermia can exacerbate cardiovascular depression. Ensure that the rats are maintained at an appropriate temperature throughout the experiment.
Moreover, i will start use of urethane anesthesia for my experiment. If i have any solution/trouble then i will update you.
Dear Aamir Sharif, thank you very much for your advice! In this case, the animals had a complex problem (hypothermia + hypoxia and hypercapnia due to a malfunction of the ventilation apparatus).
Dear Valery Sevrukevitch in this scenario where the the malfunction of the ventilation apparatus:
1: Inadequate oxygen intake, leading to hypoxia. Oxygen is essential for cellular metabolism, and insufficient levels can compromise the normal functioning of tissues and organs.
2: Impaired CO2 Removal (Hypercapnia): Simultaneously, the impaired ventilation can hinder the effective removal of carbon dioxide (CO2) from the body. Elevated CO2 levels can lead to hypercapnia, which can cause
respiratory acidosis and negatively impact various physiological processes.
- Both hypoxia and hypercapnia can disrupt normal metabolic processes. Reduced oxygen availability affects cellular respiration and energy production, while elevated CO2 levels can interfere with acid-base balance.
3. Temperature Regulation (Hypothermia): The disruption in metabolic processes, particularly energy production, can impair the body's ability to generate and maintain heat. This can contribute to hypothermia, as the body struggles to regulate its temperature effectively.