Effect Of Patient Awareness About Possibility Of Occurrence Of Pain During Propofol Injection On The Rate Of Incidence And Severity Of Pain During Injection .

Propofol is the most common intravenous (IV) anesthetic agent, used for anesthesia induction and maintenance during surgeries due to its rapid onset and short duration .

However, the incidence of propofol injection pain occurs in about 20% to 90% of patients that can decrease patient satisfaction and safety .

The mechanism of propofol injection pain has not been known yet, but many factors are involved that include the intrinsic drug property (e.g. emulsion composition, pH of the formulation, temperature, injection volume and osmolarity) .

As the lipid solvent irritates the venous intima and triggers a local kallikrein kinin cascade by discharging bradykinin and inflammatory factors, and injection pain occurs when peripheral nerve endings are directly exposed to propofol .

Other factors, including the site of injection, speed of injection, vein size, blood buffering, sex and simultaneous use of different drugs, seem to affect the incidence and severity of propofol injection pain .

The incidence and the severity of pain following propofol injection is increased in peripheral site of injection , smaller size of the vessels and slow injection and the pain can be reduced by rapid injection of propofol into the large sized veins as veins of antecubital fossa, however, this is not always practical in clinical practice .

Propofol injection pain is more common and more sever in females than males and the suggested reason of gender difference is due to the mechanical effect that male has a larger venous size than female while another factor suggested is the difference of pain sensitivity observed between the gender.

Low education level also increases the incidence and the severity of propofol injection pain as high education level will help during the patients' preoperative preparations and will reduce preoperative anxiety .

Psychogenic factors such as anxiety, depression, and fear of pain are frequently observed in patients undergoing elective surgery. Among these, preoperative anxiety and pain sensitivity has been the most important factors .

Preoperative anxiety activates the release of neuroendocrine mediators related to stress response and negatively affects anesthetic methods, surgical recovery, and postoperative pain levels .

Awareness of patient about propofol injection pain can affect patient anxiety and stress that will be reflected on incidence and severity of occurance of propofol injection pain. In our study the effect of patient awareness on propofol injection pain will be evaluated after adequate using of the pharmacological and non-pharmacological therapy that have been demonstrated to be effective in attenuating injection pain.

Many approaches have been recommended to decrease propofol injection pain including both pharmacological (e.g. pre-treatment with Paracetamol , lidocaine, magnesium sulfate, ketamine , ondansetron , Granisetron ,and and triglycerides ) .

It is generally approved that lidocaine is an adequate anesthetic that precludes injection pain. However, its adverse cardiovascular and hemodynamic effects and swelling at its injection site require to be further studied .