tently nicking a piece of the bowel or burning the patient. Instead of
inserting an ultrasonic instrument into the surgical field along the
lower part of the abdomen, it's safer to maneuver it along the anterior
abdominal wall, away from vital organs.
4. Dangerous touches
Direct coupling occurs when there's a transfer of electrosurgical ener-
gy from one conductor to another, such as when the surgeon inadver-
tently touches an electrosurgery device to another instrument or acti-
vates the device in close proximity to uninsulated metal objects such
as clips or staples. To avoid direct coupling, surgeons should always
keep the tip of the electrosurgery instrument in view, be the sole per-
son in the OR who activates the instrument and never activate the
energy when the instrument is touching a trocar.
5. Unexpected energy flows
Capacitive coupling occurs when the electrical circuit is transferred
from an instrument's active electrode through intact insulation — an
internal organ, for example — to adjacent conductive material without
direct contact. Factors that increase the risk of capacitive coupling
include using a high-voltage setting like coagulation; the laparoscopic
cannula diameter (for example, the risk is greater with when energy is
delivered through a 5mm instrument than through a 11mm instrument);
and activating the instrument when the electrode isn't in contact with
tissue, a practice that increases the voltage; and any activation over pre-
viously desiccated tissue due to the tissue's high resistance to the electri-
cal current flow.
With these risk factors in mind, you can avoid capacitive coupling
by reducing your devices to lowest possible wattage setting.
Additionally, surgeons should activate an instrument only when its tip
N O V E M B E R 2 0 1 9 • O U T PA T I E N T S U R G E R Y. N E T • 7 9
