Embolism
The Nd:YAG laser system has been associated with venous gas embolism.
Embolization has been a particular problem during hysteroscopic surgery with Nd:YAG
contact probes when the gas coolant for the sapphire probe tip has accidentally inflated
the uterine cavity. In 1989, this technique resulted in five widely publicized cases
involving four deaths.[6]
In another report, uterine
insertion of a sheathed quartz fiber (with coaxial coolant gas running) produced
an immediate, massive, and fatal gas embolism.[36]
The laser and its contact probe were not directly responsible for the injury, but
a liquid (saline) coolant is strongly preferred during hysteroscopy. If a coolant
gas must be used, CO2
produces less damage after embolization than nitrogen
or air. If uterine distention is achieved with saline rather than with gas, a fluid
overload similar to that seen during transurethral prostate surgery is possible.
[37]
Venous gas embolization also has been reported during Nd:YAG resection
of tumor in the trachea[38]
[39]
and during various types of laparoscopic and endoscopic procedures.[40]
[41]
A laser coolant malfunction during laparoscopic
ablation of endometriosis at the University of California, San Francisco, resulted
in complete subcutaneous air emphysema, from which the patient recovered after a
benign course. During laparoscopic surgery with CO2
insufflation, mechanical
hyperventilation should be instituted and adjusted to compensate for intra-abdominal
CO2
absorption and cephalad displacement of the diaphragm. Continuous
airway CO2
monitoring is highly recommended for detection of embolization
or hypercapnia.
