[Prospects of the Application of Photoacoustic Technique in Microcirculation Imaging Research on the Acupoints Sensitization].

Research on the imaging of acupoint sensitization is inadequate, especially at the microcirculation level. Photoacoustic imaging is one of the main techniques used in microcirculation imaging, and has the characteristics of high contrast, high detection depth and high sensitivity for tissue function. In the present paper the authors briefly introduce photoacoustic imaging and review research advances in photoacoustic imaging of microcirculation from the aspects of structure and function. The photoacoustic technique can three-dimensionally image and quantitatively examine microcirculation structure to the depth of interest tissues with high spatial resolution, and can dynamically measure total hemoglobin concentration and its oxygenation level, blood flow velocity, oxygen metabolism level, vasoconstriction, vasodilation, and hemodynamics of a target vessel in real time. Based on these factors, the prospects of the application of photoacoustic imaging are debated. The authors propose that photoacoustic imaging is appropriate for research on the sensitization of microcirculation in acupoints and can be applied to sensitized acupoints locally or in the brain, which is expected to further determine characteristic changes in the microcirculation of sensitized acupoints and enrich the specific connotation of the central sensitization of acupoints.

[Effects of norepinephrine on the therapeutic effect of nitric oxide inhalation in the treatment of acute respiratory distress syndrome in goat].

OBJECTIVE: To observe effects of norepinephrine (NE) on the therapeutic effects of nitric oxide (NO) inhalation in goats with endotoxin-induced acute respiratory distress syndrome (ARDS). METHODS: A model of septic ARDS was reproduced by an intravenous infusion of low dose endotoxin in six goats, and then these animals were treated with 40 x 10(-6) NO inhalation. After 30 minutes, intravenous infusion of NE in dose of 0.5 microg x kg(-1) x h(-1) was given. The dynamic changes in gas exchange and hemodynamics were measured with the aid of Swan-Ganz catheter and arterial blood gas analysis before and after the onset of ARDS, 30 minutes after NO inhalation and administration of NE. RESULTS: Inhalation of NO rapidly reduced mean pulmonary arterial pressure (MPAP), increased PaO(2), decreased alveolar-arterial partial pressure of oxygen difference (P (A-a) O(2)) and intrapulmonary shunt fraction (Qs/Qt) in septic ARDS goats. These changes were more pronounced when NE was given compared with NO inhalation alone. The combination of NO inhalation and NE infusion resulted in an increase in mean arterial pressure. CONCLUSION: Norepinephrine enhances the beneficial effect of nitric oxide inhalation on lung gas exchange in goats with endotoxin induced acute respiratory distress syndrome.

[Effect of combination of nitric oxide inhalation and inverse ratio ventilation in endotoxin-induced acute respiratory distress syndrome in sheep].

OBJECTIVE: To observe the effect of combination of nitric oxide (NO) inhalation and inverse ratio ventilation (IRV) on oxygenation and hemodynamics in endotoxin-induced acute respiratory distress syndrome (ARDS) in sheep. METHODS: Sheep ARDS model was induced by an intravenous infusion of low dose endotoxin, and then animals were randomly divided into two groups. (1) NO group (n=6), inhalation of 40x10(-6) nitric oxide. (2) Combination group (n=6), receiving mechanical ventilation with IRV (inspiratory-to-expiratory ratio of 2:1) and inhalation of 40x10(-6) NO. The dynamic changes in gas exchange and hemodynamics were measured with the aid of Swan-Ganz catheter and arterial blood gas analysis before and after the onset of, ARDS and 30 minutes after treatment. RESULTS: The combination of IRV and 40x10(-6) NO inhalation rapidly reduced mean pulmonary arterial pressure (MPAP), increased PaO(2), decreased P((A-a))O(2), and Qs/Qt without inducing significant change in systemic hemodynamics, and it was a more effective method of correcting hypoxemia than inhalation of nitric oxide alone. NO inhalation did not change the airway pressure of the model, but the combined treatment resulted in reduction of peak inspiratory pressure and increase of mean airway pressure. CONCLUSION: The combined use of IRV and NO inhalation has an additive effect on improving oxygenation in endotoxin-induced acute respiratory distress syndrome in sheep.