Using opioids in the clinical practice of anesthesia was astonishing. They are good
analgesics and used widely to modulate perioperative pain, but analgesia with these drugs can
be associated with many side effects that may lead to prolongation of hospital stay and
recovery period like respiratory depression, delirium, impaired gastrointestinal function,
urine retention, post-operative nausea and vomiting (PONV), and addiction. The most
significant opioid side effect is respiratory depression. This is especially important in
patients suffering from obesity. Obese patients already have a restrictive lung disease
leading to decrease in functional residual capacity and total lung compliance. Anesthetics
and analgesics specially opioids make these respiratory problems become worse with increasing
the incidence of hypoxia. These side effects can be avoided by using opioid free anesthesia
(OFA) techniques.
Opioid free anesthesia recently become more applicable and popular in different centers, it
provides pain control with marked reduction in opioid consumption. However, researches and
studies still unable to explore definite explanations or techniques regarding it. The base of
OFA is that not only one drug can replace opioids. It is a multimodal anesthesia. Multiple
drugs are used to achieve it. They are hypnotics,N-methyl-D-aspartate (NMDA) antagonists
(ketamine, magnesium sulfate), sodium channel blockers (local anesthetics), anti-inflammatory
drugs (NSAID, dexamethasone), and alpha-2 agonists (dexmedetomidine, clonidine). Regional
anesthesia and nerve blocks also have a role. In this study, using OFA the investigators are
hoping to achieve a good quality of care to obese patients helping in fast track surgery with
less complications and so shorter period of hospital stay