Circulation 83,045 • Volume 22, No. 4 • Winter 2007   Issue PDF

Potential Safety Hazard Associated With “Green-light” Laser Surgery

James Hardy, MD; William Camann, MD

To the Editor

Figure 1

Figure 1: Orange goggles make blue labels appear as shades of gray.

Anesthesia providers frequently use size and color cues on syringes and medication labels to assist with rapid product identification. We recently experienced a potential safety hazard during “green light” laser resection of the prostate. “Green light” laser surgery involves passing a high powered Nd:YAG laser through a KTP crystal. This doubles the frequency and halves the wavelength of the laser producing a visibly green laser, which is highly absorbed by blood rich tissue. This emerging technique has several advantages over other surgical techniques and it is likely that “green light” laser prostate resection will become more prominent.1 During this type of surgery, operating room personnel must wear appropriate protective eye shields, matched to attenuate light in the wavelength of the laser. In the case of the “green light” laser, the goggles are orange (a type of eye shield also commonly known as a “blue-blocker”). When using these goggles, the familiar blue color of opioid labels is transformed to be indistinguishable from the gray-scale labels used for local anesthetics (Figure 1). We wish to alert the anesthesiology community of this potential hazard. The lesson is a basic one—regardless of product size, shape, color, or other visual or tactile cues, one must always read the label.

James Hardy, MD
William Camann, MD
Boston, MA


1. Hanson R, Zornow M, Conlin M, Brambrink A. Laser resection of the prostate: implications for anesthesia. Anesth Analg 2007;105:475-9.