The aim of this work is to compare two protocols (ketamine-fentanyl-midazolam versus thiopental-fentanyl-midazolam) for induction of anesthesia in patients with septic shock aiming to find the most safe protocol with regards to hemodynamic status of patients.

Induction of anesthesia in hemodynamically compromised patients is a challenge for every anesthetist. Most of the intravenous induction agents have a negative effect on arterial blood pressure and cardiac output. Theoretically, the "ideal" emergency induction intravenous anesthetic should achieve rapid hypnosis and maintain the hemodynamic stability Ketamine has been reported as an induction anesthetic with a sympathomimetic activity. In patients with intact autonomic nervous system ketamine increases heart rate, cardiac output, and arterial blood pressure (ABP). Despite its sympathomimetic activity in hemodynamically stable patients, the hemodynamic response to ketamine in unstable cardiovascular conditions is not clear No studies to the best of our knowledge compared Ketamine and low dose thiopental in rapid sequence induction of anesthesia in hemodynamically unstable patients.

In this study, patients with severe sepsis or septic shock scheduled for surgery will be assigned to receive either ketamine or thiopental for induction of anesthesia. After induction of anesthesia, endotracheal tube will be inserted aided by succinyl choline. Invasive blood pressure will be monitored through a transducer connected to arterial catheter. Electrical velocimetry (cardiometry) device will be used for non-invasive monitoring of cardiac output and stroke volume.

Inclusion Criteria:

• Sepsis patients with shock index (heart rate divided by systolic blood pressure) >0.7. or Sepsis patients with norepinephrine infusion.

Exclusion Criteria:

• Traumatic brain injury
• Cerebrovascular disorders