Vapocoolant Spray for Numbing Small Boils Before Incision and Drainage

Cutaneous abscesses (boils) are collections of pus or infection in the skin, and are a frequent reason for emergency department visits. The only proven cure for abscesses is cutting them open and allowing the infection to drain, but this procedure is often painful. Currently, the usual method of pain control is to inject a numbing medication (lidocaine) into the site, but this injection itself is often painful and sometimes does not offer full pain relief. Although there has been some research into the use of non-injected numbing agents as another option, no studies have looked at the use of numbing sprays (vapocoolant) in this context specifically. The hypothesis of this study is that numbing spray is as good as injected numbing medication at relieving pain in patients having small abscesses opened and drained. This theory will be tested by taking two groups of patients having small abscesses drained in the Emergency Department, and assigning one group to get a numbing injection, and the other to get a numbing spray. Their levels of pain and satisfaction will be recorded before, during, and after the procedure, and the two groups will be compared.

Hypotheses: Patients would have a similar amount of pain with incision and drainage using local infiltration of anesthetic as with application of a vapocoolant spray and the pain of the administration of anesthesia would be similar or reduced with the use of the vapocoolant spray. Specific aims: 1.Non-inferiority in pain of anesthesia administration and incision and drainage of small abscesses by finding no significant difference of patient pain as measured on the VRNS scale. 2. Show that patients were willing to undergo anesthesia again with a vapocoolant spray as assesed by the Likert scale Long term goals- To implement the use of vapocoolant sprays as an alternative form of anesthesia for incision and drainage of abscesses The primary outcome measure for this study would be the finding of no significant difference in the pain as measured by the VRNS between the two arms for administration of anesthesia. Secondary measures would be finding no significant difference in VRNS for incisional and drainage, and change in VRNS from presentation to anesthesia, and to incision and drainage, willingness of the patient to choose the allocated sprayin the future, and unexpected events. Initial medical assessment will be made by an attending/senior resident in accordance with established clinical procedures, including the history, physical examination, and vital signs. If by clinical assessment the patients meet eligibility criteria, then they will be approached by a research associate for screening, informed consent process, enrollment in the study, and data collection. Following the screening questionnaire, the research associate will hold thorough discussion about the study. The patients will be given as much time as they require to understand and make an informed decision. A formal written consent will be obtained if patients agree to participate. After the patient understands and signs the informed consent form, they will be randomized to either the placebo group or treatment group by using a randomization scheme. The treating physician will measure erythema and induration using a measuring tape, estimate the amount of fluctuance as small, moderate, or large, and note the location of the abscess. Once randomized, subjects will be given a VRNS scale to rate their pain upon initial presentation The treating physician will clean the abscess with chlorhexidine solution then either spray the skin overlying the abscess with 1,1,1,3,3-Pentafluoropropane and 1,1,1,2-Tetrafluoroethane spray (Gebauer's Pain Ease® Medium Stream Spray) at a distance of 12 cm from the site for a duration of 2 seconds or infiltrate the abscess with 2% lidocaine with epinepherine (amount determinted by treating physician). Any reactions to the vapocoolant administration will be noted. The abscess will then be incised with a No. 11 surgical scalpel, and a cotton tipped applicator will be used to break up loculations within the abscess cavity. The method of I&D, and decision to probe to break-up loculations will be standardized, but the degree of probing, and decision to pack will be left to the discretion of the treating physician. Subjects will be asked by the research assistant to describe the discomfort of the abscess using the Visual Numerical Rating Scale (VRNS) during vapocoolant administration, during incision of the abscess, and after the procedure is complete.

Abscess, Boils, Anesthetics, Local, Lidocaine, Vapocoolant, 1,1,1,3,3-Pentafluoropropane, 1,1,1,2-Tetrafluoroethane

Lidocaine injection will be used for anesthesia prior to incision and drainage. 2% Lidocaine with epinephrine will be injected into the abscess site. Amount injected will be per physician discretion.

Vapocoolant spray will be used for anesthesia prior to incision and drainage. The spray will be administered to the abscess site for a duration of 2 seconds, from a distance of 12 cm.

Visual Numeric Rating Scale (VNRS) for pain level during incision and drainage of the abscess on Day 1.

Difference between the VNRS pain scale values collected just prior to anesthesia administration, and at the moment of anesthesia administration, on Day 1.

Difference between the VNRS pain scale values collected just prior to anesthesia administration, and at after all aspects of incision and drainage are complete, on Day 1.

Willingness of the subject to use their assigned method of anesthesia again if they were to require the same procedure in the future. Measured once on Day 1.

Inclusion Criteria: Greater than or equal to 18 years old Able to consent Has cutaneous abscess less than or equal to 2 centimeters requiring incision and drainage in the Emergency Department Exclusion Criteria: Less than 18 years old Unable to consent Pregnant or breastfeeding Prisoner or in police custody Known sensitivity to vapocoolant or lidocaine Cold hypersensitivity Chronic steroid use Peripheral neuropathy Diabetes HIV Malignancy Immunosuppressive state Sickle cell disease Sarcoidosis Abscess greater than 2 centimeters in any dimension Abscess requiring procedural sedation and analgesia for incision and drainage, or further intervention outside the Emergency Department Abscess located on the hands, feet, face, or perineal areas Pilonidal cyst hidradenitis suppurativa Not a good candidate per attending physician

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