[Correlation of Krebs Von Den Lungen-6（KL-6） Expression and Perioperative Pulmonary Function in Adults Receiving Continuing Low-volume Ventilation during Valve Surgery].

OBJECTIVE: To investigate the influence of continuous low-volume ventilation in cardiopulmonary bypass (CPB) on the expression of krebs von den lungen-6 (KL-6) and perioperative pulmonary function in adults undergoing valve surgery. METHODS: From 2017 Sept. to 2018 Jan., 60 patients who received valve replacement surgery were prospectively comprised in this study. We randomly allocated these patients into control group ( n=30, non-ventilation) and experimental group ( n=30, continuous low-volume ventilation during CPB). At different perioperative time points, we identified the dynamic changes of pulmonary function and biomarkers which expressed in serum and bronchoalveolar lavage fluid (BALF). Meanwhile, we also compared perioperative clinical outcomes of the two groups. RESULTS: The expression of serum KL-6 and BALF KL-6 in the two groups were both statistically significant（ P＜0.05）. The oxygenation index increased with time and reached to the top point at T 1, then subsequently decreased with time ( P＜0.05). The alveolar-arterial oxygen tension difference (P A-aO 2) in the two groups fluctuate with time, the differences have no statistical significance. According to linear correlation, the serum KL-6 level was negatively correlated with oxygenation indexes ( r=－0.525, P=0.003), while it was positively correlated with P A-aO 2 ( r=0.489, P=0.006). There were no significant differences between the two groups in clinical outcomes. CONCLUSION: Continuing low-volume ventilation during CPB could decrease the expression level of KL-6, while it has no significant influence on perioperative outcomes.

Bidirectional pressure: a mini review of ventilator-lung-kidney interactions.

Acute kidney injury and respiratory failure that requires mechanical ventilation are both common complications of critical illnesses. Failure of either of these organ systems also increases the risk of failure to the other. As a result, there is a high incidence of patients with concomitant acute kidney injury and the need for mechanical ventilation, which has a devasting impact on intensive care unit outcomes, including mortality. Despite decades of research into the mechanisms of ventilator-lung-kidney interactions, several gaps in knowledge remain and current treatment strategies are primarily supportive. In this review, we outline our current understanding of the mechanisms of acute kidney injury due to mechanical ventilation including a discussion of; 1) The impact of mechanical ventilation on renal perfusion, 2) activation of neurohormonal pathways by positive pressure ventilation, and 3) the role of inflammatory mediators released during ventilator induced lung injury. We also provide a review of the mechanisms by which acute kidney injury increases the risk of respiratory failure. Next, we outline a summary of the current therapeutic approach to preventing lung and kidney injury in the critically ill, including fluid and vasopressor management, ventilator strategies, and treatment of acute kidney injury. Finally, we conclude with a discussion outlining opportunities for novel investigations that may provide a rationale for new treatment approaches.

Associations between unit workloads and outcomes of first extubation attempts in extremely premature infants below a gestational age of 26 weeks.

Objective: The objective was to explore whether high workloads in neonatal intensive care units were associated with short-term respiratory outcomes of extremely premature (EP) infants born <26 weeks of gestational age. Methods: This was a population-based study using data from the Norwegian Neonatal Network supplemented by data extracted from the medical records of EP infants <26 weeks GA born from 2013 to 2018. To describe the unit workloads, measurements of daily patient volume and unit acuity at each NICU were used. The effect of weekend and summer holiday was also explored. Results: We analyzed 316 first planned extubation attempts. There were no associations between unit workloads and the duration of mechanical ventilation until each infant's first extubation or the outcomes of these attempts. Additionally, there were no weekend or summer holiday effects on the outcomes explored. Workloads did not affect the causes of reintubation for infants who failed their first extubation attempt. Conclusion: Our finding that there was no association between the organizational factors explored and short-term respiratory outcomes can be interpreted as indicating resilience in Norwegian neonatal intensive care units.