A randomized clinical trial for the timing of tracheotomy in critically ill patients: factors precluding inclusion in a single center study.

INTRODUCTION: We investigated the potential benefits of early tracheotomy performed before day eight of mechanical ventilation (MV) compared with late tracheotomy (from day 14 if it still indicated) in reducing mortality, days of MV, days of sedation and ICU length of stay (LOS). METHODS: Randomized controlled trial (RCT) including all-consecutive ICU admitted patients requiring seven or more days of MV. Between days five to seven of MV, before randomization, the attending physician (AP) was consulted about the expected duration of MV and acceptance of tracheotomy according to randomization. Only accepted patients received tracheotomy as result of randomization. An intention to treat analysis was performed including patients accepted for the AP and those rejected without exclusion criteria. RESULTS: A total of 489 patients were included in the RCT. Of 245 patients randomized to the early group, the procedure was performed for 167 patients (68.2%) whereas in the 244 patients randomized to the late group was performed for 135 patients (55.3%) (P <0.004). Mortality at day 90 was similar in both groups (25.7% versus 29.9%), but duration of sedation was shorter in the early tracheotomy group median 11 days (range 2 to 92) days compared to 14 days (range 0 to 79) in the late group (P <0.02). The AP accepted the protocol of randomization in 205 cases (42%), 101 were included in early group and 104 in the late group. In these subgroup of patients (per-protocol analysis) no differences existed in mortality at day 90 between the two groups, but the early group had more ventilator-free days, less duration of sedation and less LOS, than the late group. CONCLUSIONS: This study shows that early tracheotomy reduces the days of sedation in patients undergoing MV, but was underpowered to prove any other benefit. In those patients selected by their attending physicians as potential candidates for a tracheotomy, an early procedure can lessen the days of MV, the days of sedation and LOS. However, the imprecision of physicians to select patients who will require prolonged MV challenges the potential benefits of early tracheotomy. TRIAL REGISTRATION: Controlled-Trials.com ISRCTN22208087 . Registered 27 March 2014.

Evaluation of the PaO2/FiO2 ratio after cardiac surgery as a predictor of outcome during hospital stay.

BACKGROUND: The arterial partial pressure of O2 and the fraction of inspired oxygen (PaO2/FiO2) ratio is widely used in ICUs as an indicator of oxygenation status. Although cardiac surgery and ICU scores can predict mortality, during the first hours after cardiac surgery few instruments are available to assess outcome. The aim of this study was to evaluate the usefulness of PaO2/FIO2 ratio to predict mortality in patients immediately after cardiac surgery. METHODS: We prospectively studied 2725 consecutive cardiac surgery patients between 2004 and 2009. PaO2/FiO2 ratio was measured on admission and at 3 h, 6 h, 12 h and 24 h after ICU admission, together with clinical data and outcomes. RESULTS: All PaO2/FIO2 ratio measurements differed between survivors and non-survivors (p < 0.001). The PaO2/FIO2 at 3 h after ICU admission was the best predictor of mortality based on area under the curve (p < 0.001) and the optimum threshold estimation gave an optimal cut-off of 222 (95% Confidence interval (CI): 202-242), yielding three groups of patients: Group 1, with PaO2/FIO2 > 242; Group 2, with PaO2/FIO2 from 202 to 242; and Group 3, with PaO2/FIO2 < 202. Group 3 showed higher in-ICU mortality and ICU length of stay and Groups 2 and 3 also showed higher respiratory complication rates. The presence of a PaO2/FIO2 ratio < 202 at 3 h after admission was shown to be a predictor of in-ICU mortality (OR:1.364; 95% CI:1.212-1.625, p < 0.001) and of worse long-term survival (88.8% vs. 95.8%; Log rank p = 0.002. Adjusted Hazard ratio: 1.48; 95% CI:1.293-1.786; p = 0.004). CONCLUSIONS: A simple determination of PaO2/FIO2 at 3 h after ICU admission may be useful to identify patients at risk immediately after cardiac surgery.

Troponin repercussion of defibrillation at the end of cardiopulmonary bypass.

BACKGROUND AND AIM OF THE STUDY: Cardiopulmonary bypass (CPB) is a relatively common procedure in cardiac surgery. At the end, the heart is electrically defibrillated if not already beating. External and internal cardioversion by specific catheters do not raise plasma troponin concentration, but the possible repercussion on troponin of the direct cardioversion of the heart has not been documented. METHODS: Prospective comparative trial in a surgical intensive care unit in a university hospital was conducted. The study sample comprised 364 consecutive patients undergoing cardiac surgery with CPB and without perioperative myocardial infarction. RESULTS: The number of cardioversions applied was recorded and three groups were obtained: A/no cardioversion; B/one or two cardioversions; and C/more than two cardioversions. Serum troponin I and CK-MB were determined at admission and after 6, 12, 24, and 48 hours. Significant differences were found between group C and groups A and B for troponin I and creatine kinase (CK-MB) curves, being higher for both variables in group C. CONCLUSIONS: With more than two cardioversions post-CPB, both troponin I and CK-MB may present an additional increase.