Improving Adherence to Intraoperative Lung-Protective Ventilation Strategies Using Near Real-Time Feedback and Individualized Electronic Reporting.

BACKGROUND: Postoperative pulmonary complications can have a significant impact on the morbidity and mortality of patients undergoing major surgeries. Intraoperative lung protective strategies using low tidal volume (TV) ventilation and positive end-expiratory pressure (PEEP) have been demonstrated to reduce the incidence of pulmonary injury and infection while improving oxygenation and respiratory mechanics. The purpose of this study was to develop decision support systems designed to optimize behavior of the attending anesthesiologist with regards to adherence with established intraoperative lung-protective ventilation (LPV) strategies. METHODS: Over a 4-year period, data were obtained from 49,386 procedures and 109 attendings. Cases were restricted to patients aged 18 years or older requiring general anesthesia that lasted at least 60 minutes. We defined protective lung ventilation as a TV of 6-8 mL/kg ideal body weight and a PEEP of ≥4 cm H2O. There was a baseline period followed by 4 behavioral interventions: education, near real-time feedback, individualized post hoc feedback, and enhanced multidimensional decision support. Segmented logistic regression using generalized estimating equations was performed in order to assess temporal trends and effects of interventions on adherence to LPV strategies. RESULTS: Consistent with improvement in adherence with LPV strategies during the baseline period, the predicted probability of adherence with LPV at the end of baseline was 0.452 (95% confidence interval [CI], 0.422-0.483). The improvements observed for each phase were relative to the preceding phase. Education alone was associated with an 8.7% improvement (P < .01) in adherence to lung-protective protocols and was associated with a 16% increase in odds of adherence (odds ratio [OR] = 1.16; 95% CI, 1.01-1.33; P = .04). Near real-time, on-screen feedback was associated with an estimated 15.5% improvement in adherence (P < .01) with a 69% increase in odds of adherence (OR = 1.69; 95% CI, 1.46-1.96; P < .01) over education alone. The addition of an individualized dashboard with personal adherence and peer comparison was associated with a significant improvement over near real-time feedback (P < .01). Near real-time feedback and dashboard feedback systems were enhanced based on feedback from the in-room attendings, and this combination was associated with an 18.1% (P < .01) increase in adherence with a 2-fold increase in the odds of adherence (OR = 2.23; 95% CI, 1.85-2.69; P < .0001) between the end of the previous on-screen feedback phase and the start of the individualized post hoc dashboard reporting phase. The adherence with lung-protective strategies using the multidimensional approach has been sustained for over 24 months. The difference between the end of the previous phase and the start of this last enhanced multidimensional decision support phase was not significant (OR = 1.08; 95% CI, 0.86-1.34; P = .48). CONCLUSIONS: Consistent with the literature, near real-time and post hoc reporting are associated with positive and sustained behavioral changes aimed at adopting evidence-based clinical strategies. Many decision support systems have demonstrated impact to behavior, but the effect is often transient. The implementation of near real-time feedback and individualized post hoc decision support tools has resulted in clinically relevant improvements in adherence with LPV strategies that have been sustained for over 24 months, a common limitation of decision support solutions.

Evaluation of Vasopressin for Septic Shock in Patients on Chronic Renin-Angiotensin-Aldosterone System Inhibitors.

OBJECTIVES: To compare the hemodynamic response in septic shock patients receiving vasopressin who were on chronic renin-angiotensin-aldosterone system inhibitor therapy with those who were not. DESIGN: Single-center, retrospective cohort study. SETTING: Medical and surgical ICUs at a 1,100-bed academic medical center. PATIENTS: Medical and surgical ICU patients with septic shock who received vasopressin infusion added to at least one concomitant vasopressor agent between January 2014 and December 2015, then divided into two cohorts: 1) patients who were on chronic renin-angiotensin-aldosterone system inhibitor therapy as outpatients and 2) patients who were not on chronic renin-angiotensin-aldosterone system inhibitor therapy as outpatients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure at 6 hours was 72.2 mm Hg in the renin-angiotensin-aldosterone system inhibitor group versus 69.7 mm Hg in the non-renin-angiotensin-aldosterone system inhibitor group (p = 0.298). There was no difference in mean arterial pressure at 1, 24, or 48 hours between groups. Total concomitant vasopressor requirements, based on norepinephrine equivalents excluding vasopressin, were significantly lower at 24 hours in the renin-angiotensin-aldosterone system inhibitor group versus the non-renin-angiotensin-aldosterone system inhibitor group (10.7 vs 18.1 µg/min, respectively; p = 0.007), but no significant differences were seen at the other time points assessed. There were no significant differences in ICU or hospital length of stay or mortality. CONCLUSIONS: There was no significant difference in the primary outcome of 6-hour mean arterial pressure in septic shock patients receiving vasopressin who were on chronic renin-angiotensin-aldosterone system inhibitor therapy versus those receiving vasopressin who were not on chronic renin-angiotensin-aldosterone system inhibitor therapy. Renin-angiotensin-aldosterone system inhibitor patients had lower total concomitant vasopressor requirements at 24 hours compared with non-renin-angiotensin-aldosterone system inhibitor patients.

Postoperative care of vascular surgery patients.

Vascular surgery continues to carry one of the highest postoperative morbidity and mortality rates. A detailed understanding of postoperative central nervous, myocardial, respiratory, and renal pathophysiology potentially helps to improve outcome. Current economic constraints, combined with changing intraoperative management, prompt inquiry into whether these patients can safely be managed outside of an intensive care unit setting. This article reviews whether efforts to less invasively manage these patients intraoperatively improves postoperative outcome remains under investigation, and what is known about the effects on postoperative outcome of regional anesthesia for carotid endarterectomy and endovascular treatment of aortic vascular disease.

Oxidant-antioxidant balance in acute lung injury.

ARDS is a disease process that is characterized by diffuse inflammation in the lung parenchyma. The involvement of inflammatory mediators in ARDS has been the subject of intense investigation, and oxidant-mediated tissue injury is likely to be important in the pathogenesis of ARDS. In response to various inflammatory stimuli, lung endothelial cells, alveolar cells, and airway epithelial cells, as well as activated alveolar macrophages, produce both nitric oxide and superoxide, which may react to form peroxynitrite, which can nitrate and oxidize key amino acids in various lung proteins, such as surfactant protein A, and inhibit their functions. The nitration and oxidation of a variety of crucial proteins present in the alveolar space have been shown to be associated with diminished function in vitro and also have been identified ex vivo in proteins sampled from patients with acute lung injury (ALI)/ARDS. Various enzymes and low-molecular-weight scavengers that are present in the lung tissue and alveolar lining fluid decreased the concentration of these toxic species. The purpose of this brief chapter is to review the results from various studies demonstrating increased levels of reactive oxygen-nitrogen intermediates in the alveolar spaces of patients with ALI/ARDS.