Adding Epi to Irrigation Fluid May Help Visualization in Shoulder Arthroscopy
But it is not known if this improved visualization is clinically significant. And the use of epinephrine carries the risk of cardiac events.
Mehul R. Shah, MD
Avery DM III, Gibson BW, Carolan GF. Surgeon-rated visualization in shoulder arthroscopy: a randomized blinded controlled trial comparing irrigation fluid with and without epinephrine. Arthroscopy. 2015 Jan; 31(1):12-18.
The authors of this article sought to determine whether the addition of epinephrine to arthroscopy fluid improved visualization during arthroscopy of the shoulder.
The study is double-blinded, prospective, randomized controlled trial that included 83 shoulder arthroscopies performed with or without 1 mL of 1:1000 epinephrine added to each 3 L bag of lactated Ringers used as the irrigation fluid. Forty-four patients were in the epinephrine group and 39 patients were in the control group. There were no differences between groups regarding age, sex, or anticoagulant use.
All procedures were performed in a modified lateral position by a single surgeon. At the end of each case, the surgeon completed a visual analog scale (VAS) score regarding the ease of visualization during the procedure.
No statistical differences were seen between the 2 groups in mean arterial pressure (MAP), need for blood pressure treatment during the procedure, or operative time. The findings were similar in a subset analysis of the rotator cuff repairs performed during the study.
The authors found a statistically significant difference in the surgeon-rate VAS scores for all procedures, including the rotator cuff repair subset. The median VAS for all procedures was 9 for the epinephrine group versus 7 for the control group. In the rotator cuff repair subset, the median VAS score was 9 in the epinephrine group versus 6 in the control group.
Shoulder arthroscopy is one of the most common procedures performed in orthopaedics. Adequate visualization during the procedure is critical for the procedure to be performed successfully. Interventions such as arthroscopic cannulas, hemostasis with electrocautery, maintenance of pump fluid pressure, and hypotensive anesthesia have been used to control bleeding and improve visualization.
However, these interventions are not without risk:
- Increased pump fluid pressure can cause significant swelling about the shoulder and make the case more difficult. This swelling has been reported to involve the neck, leading to concerns of airway obstruction.
- Excessive hypotension during shoulder surgery can lead to cerebral hypoperfusion and stroke.
- Second-degree burns of the chest and shoulder have been reported from excessive use of the radiofrequency cautery.
Given these complications, alternative ways to improve visualization – such as adding epinephrine to the irrigation fluid – are desired.
However, the use of epinephrine in arthroscopy fluid is not without risk either. Cases of cardiopulmonary arrest and ventricular tachycardia have been reported after shoulder arthroscopy and attributed to the use of epinephrine during surgery.
This study showed statistically significant improvement in visualization scores with the use of epinephrine in the arthroscopy fluid. Whether that is clinical significant is not know: As the authors discuss, the minimum clinically significant difference (MCSD) in the VAS score has not been established.
For the purposes of this study, the authors defined the MSCD as a difference of 2 points (20%) on the VAS scale. However, this difference may not alter the efficiency of the surgery, especially in surgeons adept at shoulder arthroscopy.
This point is supported by the fact that the addition of epinephrine did not improve OR time, amount of fluid used, need for blood pressure intervention, or improvements in pump fluid pressures in the study.
The study has additional limitations. It included only 1 surgeon who performs shoulder arthroscopy; therefore, the results may not correlate with surgeons who are less comfortable performing these procedures. A study that included multiple surgeons with various operative techniques would be more readily applicable to most orthopaedists.
Although the utilization of epinephrine may improve subjective visualization scores in this study, the clinical significance is yet to be determined. It remains an option to improve visualization if necessary, but should be used with caution, especially in individuals with cardiac risk factors.
Mehul R. Shah, MD is an Assistant Professor of Orthopaedic Surgery, Division of Sports Medicine, at NYU Langone Medical Center – Hospital for Joint Diseases, New York, New York.