A 42-year-old male was undergoing elective hernioplasty. End tidal carbon dioxide (ETC02) was found to be increased. Abdominal wall gradually showed rigidity, along with the presence of tachycardia and tachypnea. Blood gas analysis shows an increased mixed acidosis, along with a serum lactate of 3.4 mmol/L. Which of the following has most likely resulted in the present situation?