Between January 2008 and October 2011, 135 patients undergoing elective outpatient aesthetic procedures were asked to volunteer for this study. Patients who were excluded from the study were those who suffered from chronic pain, had a history of substance abuse or a recent history of long-term opioid use (used any opioid analgesics for longer than 30 days in the 5 years prior to surgery). Moreover, patients with an allergy to acetaminophen, COX-2 inhibitors, gabapentin or hydrocodone were excluded from the study. The patients were 58.4% Asian or of mixed-Asian ancestry. The remaining identified themselves as Caucasian, Filipino, part-Hawaiian, or “other.” No opioids, including morphine, meperidine, or fentanyl, were administered during the procedure. These qualifying patients were randomly divided into experimental and control groups.
The experimental group contained a total of 69 patients who were educated about the importance of “endorphins” or “natural narcotics” (these two words were used repeatedly throughout the session for better understanding). Not only were the patients educated on the side effects of opioid narcotics, including nausea and vomiting, but they were also taught the negative effects of “synthetic narcotics” or “fake narcotics” (two words also repeated for better understanding) have on the body's endorphins. The experimental group underwent two educational sessions led by the same surgeon, each lasting from 15 to 30 minutes: one session was held about two weeks before the surgical procedure, and the second session was done on the same day before the procedure. The earlier session, two weeks prior to the procedure, included both oral and written forms of communication where the patient underwent a 15 to 30 minute preoperative patient education session as well as received a handout re-emphasizing the main points about endorphins. During the pre-operative session, a schematic was used to illustrate the ligand protein-receptor nature between the mu receptor and its ligands, eg, endorphins. The surgeon explains that if synthetic narcotics, such as hydrocodone or oxycodone, are administered, they will block the receptors and thus have a dual effect of blocking the action of the natural narcotics (endorphins) as well as diminishing their production. Patients were educated that as a result, patients using opioid analgesics not only face the side effects of narcotics (nausea/vomiting), but also have more intense pain for a longer period since it takes time for the endorphins/natural narcotics to be produced.
The preoperative teaching sessions also included information about non-opioid analgesics, namely gabapentin, celecoxib, and acetaminophen. Specifically, patients learned that these drugs are known to produce analgesic effects though opioid-sparing mechanisms. Taking these medications would preserve the body's natural endorphin production and response, while avoiding the negative side effects of narcotics.
After receiving instruction, the patients had the choice to receive preoperative treatment consisting of oral administration of 600mg of gabapentin and 400mg of celecoxib 30–60 minutes before surgery. The patients who preferred no prescription of hydrocodone as well as gabapentin and celecoxib after patient education were separated into experimental group A. Experimental group B consisted of patients who received preoperative patient education, refused to take a prescription of hydrocodone, but accepted preoperative administration of gabapentin and celecoxib. Those who accepted a prescription for hydrocodone, in case acetaminophen (Tylenol) was not adequate, were put into experimental group C.
The control group consisted of 66 patients who received 600mg of gabapentin and 400mg of celecoxib 30–60 minutes before surgery, but did not receive any pre-operative oral or written patient education regarding endorphin physiology. Patients were handed prescriptions for the preoperative medications (gabapentin and celecoxib) and hydrocodone. These patients were divided into control group A (those who did not request refills on hydrocodone) and control group B (those who requested refills on hydrocodone).
All patients had access to acetaminophen (1000mg every 6 hours as needed) postoperatively. The rationale for the administration of celecoxib and gabapentin was explained to the patients by the operating surgeon during their preoperative visit, which occurred approximately 2 weeks before surgery, and was re-emphasized on the day of the procedure prior to the operation. However, control group patients did not receive preoperative education on the mechanisms of preserving endorphin function in these non-opioid analgesics. Rather, the patients were simply informed that celecoxib and gabapentin would be used for prophylaxis of postoperative pain. Additionally, 500mg of cephalexin was given to all patients 30–60 minutes before surgery for infection prophylaxis, following the surgeon's usual infection protocol. The incidence of nausea and vomiting in the post-anesthesia care unit for both control and experimental groups was recorded.
Beginning on the day of surgery and ending on the fifth post-operative day, patients were asked to self-rate their perceived level of pain intensity daily. Pain intensity was quantified using the following 0–5 scale: 0 for none, 1 for mild pain (annoying, nagging), 2 for discomforting (trouble- some, nauseating, grueling, numbing), 3 for distressing (miserable, agonizing gnawing), 4 for intense (dreadful, horrible, vicious, cramping), and 5 for excruciating pain (unbearable, torturing, crushing, tearing). This pain scale is consistent with the scale used by Parsa, et al, in their study on the combined use of celecoxib and gabapentin in postoperative pain management.6
Self-rating was done on a daily basis. If patients experienced different intensities of pain throughout the day, they were asked to record the time and intensity of their perceived pain accordingly. Patients who required analgesic medication were asked to record the date, time, type of medication (Tylenol or hydrocodone), and the intensity of their pain on a provided form.
The questionnaires were collected on postoperative day 5. The investigators calculated an average pain score for each patient over the five days. These scores were compiled and organized in the following fashion: nil to mild pain, pain score of 0 to 1.99; mild to moderate pain, pain score of 2 to 2.99; intense pain, pain score of 3 to 5. Additionally, a combined average pain score for each of the 5 subject groups was calculated. Patients' use of opioid analgesics and self-rated pain are the primary outcome measures of this study. Statistical analyses were conducted using Fisher's exact test with mid-P, two-sided values of P <.05 considered significant.