Pain control is an important aspect in patient who will undergo a medical procedure. Reducing pain will not only improves patient satisfaction and comfort, but also provide speedy and easy medical procedures application. One of the patient's concerns regarding Anesthesia is pain when needles injected intracutaneously, intramuscularly, intravenously, or intrathecally. Epidural anesthesia is one of the neuraxial block technique resulting in sympathetic, sensory, and motor block depending on the dose, concentration, and volume of the local anesthetic administered. Epidural anesthesia was performed in 118 cases (18%) of the total 672 anesthesia cases in November 2020 at the National Central General Hospital (RSUPN) Cipto Mangunkusumo. Tuohy Type is one of epidural needles commonly used in Epidural anesthesia at Cipto Mangunkusumo General Hospital. This needle's size is large enough so that it causes pain if local anesthetic is not given prior to insertion. One of the way to administer local anesthetic prior to epidural needle insertion is by skin infiltration using a needle.
Ramzi in his research found that the median Visual Analogue Scale (VAS) due to epidural needle insertion given lidocaine infiltration with a needle is 5 with a range of 0-10. Mogensen investigated differences in pain expectations and the actual pain experienced by the patient due to insertion of the Tuohy needle in epidural anesthesia infiltrated with lidocaine using a needle. The research found that the median Numeric Rating Scale (NRS) for pain expectations was 5 while the NRS for actual pain experienced by patients was 2 (p value \< 0.0001). Infiltration of local anesthetic with the needle alone is painful. Gozdemir in his research found that the pain median due to infiltration lidocaine using the needle before insertion of the epidural needle was 2 with a range of 0 up to 4.
Several alternative methods have been developed to reduce the pain of local anesthetic infiltration prior to epidural needle insertion, such as: establishing good communication with the patient during the procedure, replacing local anesthetic agents with chloroprocaine, adding bicarbonate to make lidocaine pH close to physiological pH, cooling down the skin with cryoanalgesia, local anesthetic infiltration with a smaller needle (25-30 G needle), lidocaine patch, and Eutectic Mixtures of Local Aesthetics (EMLA). Some of these alternatives still perform needle punctures that can produce pain, although to a lesser degree, and 10% of the population have a needle phobia. Non-invasive alternatives such as EMLA or cryoanalgesia cannot be a thorough solution due to the depth of analgesia generated. A study stated that the depth from skin to lumbar epidural cavity in parturient is 2-9 cm with 89% being on the 3.5-7.5 cm intervals. In leaner patients, the depth of the lumbar epidural found at 2-4 cm. Whereas EMLA only provides analgesia in depth of 2.9-4.5 mm if EMLA is applied for 60-120 minutes and 6 mm if applied for 3-4 hours. While cryoanalgesia such as vapocoolants spray works as a temporary topical analgesia by cooling the skin thereby reducing the sensitivity of pain receptors.
Needle usage, the length of time it takes to produce analgesia, transient analgesia results, and lack of depth of analgesia are the problems to present an alternative to local anesthetic infiltration that is completely pain free and adequate. A needleless injection technology can be a solution to these problems. The medicinal liquid is injected by a tool with high speed and pressure through a smooth hole. This system is expected to make the analgesia condition can be achieved quickly, painlessly, and avoiding needle phobia
