Apnea test prerequisites: eucapnia
, normotension, normothermia, euvolemia, and absence of hypoxia.
5-HT acts as a potent central ventilatory stimulant and serves to maintain upper airway patency and maintain eucapnia
via the chemoreceptor properties.
When compared with obese people who show eucapnia
, those with OHS show higher chances of developing systemic hypertension, cardiac failure, and angina.
As the animal's breathing pattern did not improve, atracurium (0.2mg[kg.sup.-1], Tracrium Injection, GlaxoSmithKline, UK) was administered intravenously and intermittent positive pressure ventilation (Penlon Nuffield 200 ventilator) was started to maintain eucapnia
(PE'C[O.sub.2] 35-45 mmHg).
Mechanical ventilation was instituted to maintain eucapnia
. Analgesia was attained with fentanyl up to a total dose of 10 [micro]g/kg.
During arousals, enhanced C[O.sub.2] (and hypoxic) chemosensitivity above eucapnia
will tend to lower the prevailing PC[O.sub.2] and increase the likelihood of the occurrence of apnoea during subsequent sleep.
In order to maintain eucapnia in the face of mass loading and abnormal chest wall mechanics, increased respiratory drive occurs (30).
In humans, leptin levels are increased in obesity, and therefore may be contributing to the augmented drive needed to maintain eucapnia in the face of mass loading (39).