Evaluation of Impact of Nitrous Oxide on PONV in Breast Surgeries
Status:
Completed
Trial end date:
2017-02-01
Target enrollment:
Participant gender:
Summary
Postoperative nausea and vomiting (PONV) is considered one of the most unpleasant
postoperative discomforts and lead to serious complications of aspiration of gastric
contents, suture dehiscence, esophageal rupture, subcutaneous emphysema, or pneumothorax. The
incidence of PONV is 30-40% in normal population and touches a peak of 75-80% in certain
high-risk groups. PONV is associated with delayed recovery and prolonged hospital stay and is
associated with significant morbidity. It may also result in delayed discharge, which is
particularly significant after potentially ambulatory surgery. Women are 2 to 3 times more
susceptible to PONV than men and breast surgery, which is primarily done in an outpatient
setting, is associated with high incidence of PONV, ranging between 15% and 84% in the
absence of prophylactic treatment.
Nitrous oxide (N2O) has analgesic and sedative properties but may potentially increase the
incidence of PONV. N2O might increase the incidence of PONV by several potential mechanisms:
(1) increase in middle ear pressure (2) bowel distension, (3) activation of the dopaminergic
system in the chemoreceptor trigger zone and (4) interaction with opioid receptors. N2O has
been demonstrated to increase the incidence of PONV in some studies but not in others. The
present study is undertaken to evaluate the effect of nitrous oxide- free general anesthesia
on the undesirable clinical outcome of PONV.