Study objectives: In maxillary nosocomial sinusitis (MNS) related to severe sepsis, nitric oxide (NO) concentration in the maxillary sinuses is drastically reduced secondarily to a downregulation of type-2 NO synthase. NO plays a major role in nonspecific immune defense of sinuses. We therefore aimed to study maxillary NO concentration during the treatment of MNS with drainage, daily lavage, and removal of any nasally introduced tube.
Patients and methods: Nine patients were studied during the first 4 days of treatment of MNS. We measured the concentration of NO gas in the maxillary sinus and in the nasal cavity, and the NO metabolite levels (nitrites/nitrates [NOx]) in the sinus lavages.
Measurements and results: Maxillary NO concentration (median [25 to 75 percentile]) increased from 70 parts per billion (ppb) [40 to 100 ppb] to 2,050 ppb (1,700 to 3,000 ppb) after 4 days of treatment of MNS (p < 0.0001). In the meantime, nasal NO increased from a median of 100 ppb (98 to 148 ppb) to 180 ppb (180 to 188 ppb) [p < 0.001]. At any time, there was a correlation between maxillary NO (logarithmic value) and nasal NO (r2 = 0.57, p < 0.0001). NOx levels remained stable in the lavages.
Conclusions: We conclude that the treatment of the sinusitis with drainage, daily lavage, and removal of the gastric tube lead to a spectacular increase of maxillary and nasal NO concentrations.