Adding a basal rate to PCA's, either continuously, or at night (recommended by the AHCPR) does not enhance patients' ability to manage their postoperative pain.
(Hoare, K., Sousa, K.H., Person, L., Ryke, P. D., & piper, J. (2000).)
Comparing three patient-controlled analgesia methods. MEDSURG Nursing, 9(1), 33-39.
Purpose:
To determine differences in pain control, side effects, symptoms, and patient acceptance of three methods of PCA;
1) on-demand bolus method
2) continuous basal infusion
3) adding continuous basal infusion to on-demand bolus method at night
Sample:
301 patients
admitted for abdominal, orthopedic, gynecologic, and thoracic surgery at two
nonprofit
Instruments: three instruments were used:
1) Pain control efficacy-self evaluation of pain using a 10-point, numeric, pain-rating scale, counts of the number of times subjects used the bolus capacity of the PCA equipment, and calculation of total milligrams of morphine or Demerol used. At 12-hour intervals (at 8 am and 8 pm) after PCA initiation, patients were asked to indicate pain level they had experienced within the last 12 hours, with 0 indicating no pain, 5 indicating moderate pain, and 10 indicating the worst pain.
2) Side effects were determined by self-report checklist of 16 symptoms of side effects associated with PCA during the previous 12 hours. Example of such symptoms included dizziness, flushing, nausea, and dry mouth
3) patient acceptability and satisfaction with pain control were determine by patient satisfaction questionnaire adapted from the quality assurance committee of the American Pain Society questionnaire. This tool contained 14 items which addressed use of the self-administrator feature of the pump, worry or upset caused by the method, the method's interference with the activities of daily living, ease of pump operation, and satisfaction with being able to control one's own pain medication.
Methods:
PCA was initiated in the PACU for all patients. Thirty-six percents of patients received a loading dose and the rest did not. The three groups did not differ in number of patients who did or did not receive a loading dose. At the preoperative visit, each patient was given instructions for operating the PCA equipment. The instructions were reviewed again in the PACU before PCA was initiated.
Group 1. On demand bolus method group was served as a treatment group. Patients received opioid analgesia for the first 48 hours postoperatively by PCA on-demand bolus. Patients self-administered medication by pushing a button. The PCA pump controls delivery of a predetermined amount of pain medication within a specified amount of time. After patients receive the maximum amount of pain medication allowed within a given period, they may push the button but no pain medication is delivered.
Group 2. Continuous basal method group was served as a treatment group. This group received pain medication by PCA on demand bolus plus continuous basal infusion. Patients in this group received a constant, controlled intravenous infusion of pain medication via the PCA pump. In addition to receiving the constant dose, they could self-administer pain medication by pushing a button.
Group 3. This group self-administered an on-demand bolus of opioid agent during the day only and received continuous basal infusion at night only.
Results
Pain control:
No significant difference in mean pain scores reported by patients at each 12 hour interval among three groups. The greatest decrease in pain scores occurred during the first 12 hours postoperatively. No significant differences among the three groups in number of patients who asked for more or different pain medication. Patients using the on-demand bolus method made the most attempts comparing to other groups on the first post-op day between 9pm to 7 am. There was no significant difference among the three methods in total milligrams of medication on the day of surgery. During the first and second post-op day, patients in the on-demand bolus method used significantly less pain medication than other groups.
Side effects/symptoms:
There are significant differences among the three methods in mean change of symptom count. The on-demand bolus (group 1) and the night basal methods of pain control (group 3) showed a decrease in number of patient-reported symptoms, whereas the continuous basal method (group 2) showed an increase. The decrease in symptoms in on-demand bolus method (gr. 1) on the first post-op day was greater than patients who used the night basal method (g. 2). ****Gr. 1 & 3 better than gr. 2, and gr. 1 better than gr. 3.*** Patient acceptance : No significant difference among groups in terms of effectiveness of pain management, number of patients concerned about pain control method, or number of patients who reported that the method interfered with activities of daily living.
Summary
The on-demand bolus
method controls pain with the least amount of medication and does not intensify
postanesthetic or postoperative symptoms. The results of the study indicate
that three methods of PCA; on-demand bolus, continuous basal plus on-demand
bolus, and on-demand bolus plus night basal methods, are equally efficient at
controlling postoperative pain within the first 48 hours after surgery in
patients receiving morphine or Demerol. Adding basal infusion to the on-demand
bolus method either continuously, or at night (recommended by the AHCPR) does
not enhance patients' ability to manage their postoperative pain.