Cardiorespiratory effects of diazepam-ketamine, xylazine-ketamine and thiopentone anesthesia in male Wistar rats-A comparative analysis

Abstract Several anesthetics are known to cause respiratory and cardiovascular depression in humans and animals; but, these diverse effects have not been extensively investigated in laboratory rodents. The objective of this study is to choose a suitable anesthetic combination for use in surgical models eg. coronary artery ligation in rats. Male Wistar rats were anesthetized with three different drugs viz. diazepam-ketamine (DK) (2.5 mg/Kg, intraperitoneally (i.p); 50 mg/Kg, i.p), xylazine-ketamine (XK) (5 mg/Kg i.p; 50 mg/Kg i.p) and thiopentone (T) (40 mg/Kg i.p) and the respiratory and cardiovascular functions were assessed after coronary artery ligation. Heart rate (HR), mean arterial pressure (MAP), partial pressure of carbon dioxide (PaCO 2 ), partial pressure of oxygen (PaO 2 ), oxygen saturation percentage (O 2 sat (%)), arterial blood pH and rectal body temperature were studied in detail. During the anesthetic regime, HR was lower till 60 min in XK and T ligated group (333 ± 6; 304 ± 8 beats/min) and it was near normalcy in the case of DK ligated group (394 ± 6 beats/min). Significant respiratory depression was particularly reflected in the T ligated group with an increase in PaCO 2 at 30 min (40.32 ± 2.64 mmHg), which decreased to 38.2 ± 2.23 mmHg at 60 min. Throughout the investigation, DK showed the least overall effects compared to XK and T on respiratory functions. Thus, DK could be considered to be a suitable anesthetic for use in a surgical model such as coronary artery ligation in albino rats.