Comparison of Large Antecubital Vein Versus Small Vein on Dorsum of Hand for the Prevention of Propofol Injection Pain

Propofol is the most commonly used drug for induction of anesthesia because of its rapid onset, short duration of action, easy titration and with fewer hemodynamic Effects. Hypersensitivity reaction with Propofol is very rare and reported incidence of pain on injection is 26-70%. As Propofol is extensively used for the induction of anesthesia its pain on injection cannot be neglected. Propofol was launched for clinical practice in 1977 in Cremophor form and reformulation as aqueous solution was launched in 1986, an oil-in water emulsion containing soybean oil. Many interventions have been tried for the reduction of pain on Propofol aqueous solution injection. Unfortunately none of the intervention was found to be successful to abolish the pain completely. So far the mechanism of pain on Propofol injection is not clear.

The everyday uses of Propofol in many settings of the hospitals mandate its painless use. The proposed mechanisms of pain are release of local mediators and / or direct irritant effect of Propofol on nerve endings.

In this study the investigators combined two interventions, Propofol - lidocaine admixture and different size of veins, to evaluate the pain on Propofol injection. The admixture of Propofol-lidocaine was injected through two different sizes of veins which are commonly used for intravenous cannulations, large antecubital vein and small vein on dorsum of hand.

Propofol is a commonly used drug for induction of anesthesia and sedation in intensive care, emergency room and for endoscopic procedures. Unfortunately, despite its popularity pain on its injection is still unresolved problem. The exact mechanism of this pain is not clear so far.

Some investigators suggest that the lipid solvent for Propofol activates the plasma kallikrein-kinin system and produces bradykinin. This modifies the injected local vein causes vasodilation and hyper-permeability. This modification of the peripheral vein may increase the contact between the aqueous phase Propofol and free nerve endings of the vessel resulting in Pain.Others investigators believe that Propofol as a member of phenol group can have direct irritant effect on local vein by stimulating nociceptors and free nerve endings giving rise to an immediate sensation of pain. Based on these assumptions of Propofol induced pain pathway, different investigators postulated different interventions to alleviate this problem. Different pharmacological and non-pharmacological interventions have been tried for the reduction of pain on Propofol injection. The injection of Propofol through large antecubital vein was considered as a superior method than any other non pharmacology measures like changing the temperature of Propofol, large intravenous catheter and speed of injection.Pharmacological interventions with different drugs have been tried, pretreatment with lidocaine with venous occlusion. Propofol-lidocaine admixture, pretreatment with Ketamine, opioids,non-steroidal anti-inflammatory drugs ,magnesium sulfate, ondansetron, tramadol, acetaminophen, dexamethasone and Propofol emulsions containing medium and long chain triglycerides have been studied and reviewed extensively.