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Heparin-induced thrombocytopenia (HIT) presents a unique challenge in patients requiring orthotopic heart transplantation (OHT). We sought to pool the existing evidence in a systematic review.Electronic search was performed to identify all relevant studies on OHT in patients with HIT. Patient-level data for 33 patients from 21 studies were extracted for statistical analysis.Median patient age was 51 [IQR 41, 55] years, with 75.8% (25/33) males. All patients had a clinical diagnosis of HIT, and anti-PF4/Heparin antibodies were positive in 87.9% (29/33). Median lowest reported platelet count was 46 × 10Heparin use during OHT may be associated with less adverse effects compared to use of other anticoagulants with no difference in 30-day mortality.

Background The number of adults referred to high-volume centers for extracorporeal membrane oxygenation (ECMO) is increasing. Outcomes of patients requiring transport are not well characterized, and referral guidelines are lacking. This study describes the experience and outcomes of a single high-volume center. Methods A retrospective study was performed that included adults undergoing ECMO between June 2009 and December 2015. Patient characteristics and outcomes were acquired from the medical record. Logistic regression was used to identify predictors of survival to hospital discharge. The Kaplan-Meier method was used to depict rates of survival. Results Of 133 patients, 77 (57.9%) underwent venoarterial (VA) ECMO and 56 (42.1%) underwent venovenous (VV) ECMO. Median transport distance was 88.8 miles (range 0.2–1,434 miles). Median duration of support was 6 days (range, 1–32.5 days). Age older than 60 years, pulmonary hypertension, and body mass index (BMI) greater than 30 were associated with worse survival to discharge for VA ECMO; a history of hypertension and presence of left ventricular (LV) vent were associated with better survival. Age older than 60 years and diabetes were associated with worse survival to hospital discharge for VV ECMO. Survival to decannulation was 66.2% and 76.8%, and to hospital discharge it was 48.1% and 69.6% for VA and VV ECMO, respectively. Of hospital survivors, Kaplan-Meier estimates of 1-year survival were 82.4% and 95.5% for VA and VV, respectively. Conclusions Outcomes are favorable after transport to high-volume ECMO centers. Guidelines and infrastructure for short- and long-distance ECMO transport is imperative for the efficient and successful management of these patients.

A decision support, rule-based oxygenation advisor that provides guidance for setting positive end expiratory pressure (PEEP) and fractional inhaled oxygen concentration (FIO2) for patients with respiratory failure is described. The target oxygenation goal is to achieve and maintain pulse oximeter oxygen saturation (SpO2) ≥88 and ≤95 %, as posited by the Acute Respiratory Distress Syndrome Network, by recommending appropriate combinations of PEEP and FIO2. For patient safety, the oxygenation advisor monitors mean arterial blood pressure (MAP) to ensure it is ≥65 mmHg for hemodynamic stability and inspiratory plateau pressure (Pplt) so it is ≤30 cm H2O for lung protection. The purpose of this validation study was to compare attending physicians’ recommendations to those recommendations of the oxygenation advisor for setting PEEP and FIO2. Adults with respiratory failure (n = 117) receiving ventilatory support were studied. PEEP, FIO2, SpO2, MAP, and Pplt are input variables into the advisor. Recommendations to increase, maintain, or decrease PEEP and FIO2 are the oxygenation advisor’s output variables. Physicians’ recommendations for setting PEEP and FIO2 were recorded; the oxygenation advisor’s recommendations were also recorded for comparison. At all times, ventilator settings were based on recommendations from attending physicians. PEEP ranged from 2 to 22 cm H2O and FIO2 ranged from 0.30 to 0.65. A total of 326 recommendations by the oxygenation advisor and attending physicians were made to increase, maintain, or decrease PEEP and FIO2. There was a very significant relationship (p

In the previous issue of Critical Care, we read with interest the article by Al-Rawas and colleagues [1], who proposed a method for the determination of respiratory system mechanics (RSM) in diff erent ventilatory modes. We have some concerns regarding the applicability of the described method during pressure support ventilation (PSV). In particular, all equations proposed in the article contain a term called ‘inhaled fl ow rate’. Since there is no constant inspiratory fl ow during PSV, it is unclear how the authors determined its exact value. Furthermore, all of these equations are transformations of the equation of motion of the respiratory system and require the knowledge of the inspiratory driving pressure, for which the authors apparently used the inspiratory airway pressure. However, in PSV, the patients’ spontaneous breathing activity contributes to inspiratory driving pressure to a variable degree [2]. It would be interesting to know how the authors took the patients’ muscular eff ort (P mus ) into account. Finally, we would like to know why the numbers of patients in the PSV and in the volume-controlled continuous mandatory ventilation groups diff er from the numbers of measurements plotted in the corresponding fi gures. For example, 23 patients were in the PSV group (according to Table 1), but 25 measure ments are shown in Figure 4a,b and only 14 are shown in Figure 4c. A non-invasive determination of RSM during PSV is certainly helpful in a clinical setting, and we would appreciate if the authors provided a detailed description of how they handled the non-constant qualities of fl ow and P mus during PSV.

We hypothesized that non-invasively determined work of breathing per minute (WOB(N)/min) (esophageal balloon not required) may be useful for predicting extubation outcome, i.e., appropriate work of breathing values may be associated with extubation success, while inappropriately increased values may be associated with failure.Adult candidates for extubation were divided into a training set (n = 38) to determine threshold values of indices for assessing extubation and a prospective validation set (n = 59) to determine the predictive power of the threshold values for patients successfully extubated and those who failed extubation. All were evaluated for extubation during a spontaneous breathing trial (5 cmH(2)O pressure support ventilation, 5 cmH(2)O positive end expiratory pressure) using routine clinical practice standards. WOB(N)/min data were blinded to attending physicians. Area under the receiver operating characteristic curves (AUC), sensitivity, specificity, and positive and negative predictive values of all extubation indices were determined.AUC for WOB(N)/min was 0.96 and significantly greater (p 0.05) than AUC for breathing frequency at 0.81, tidal volume at 0.61, breathing frequency-to-tidal volume ratio at 0.73, and other traditionally used indices. WOB(N)/min had a specificity of 0.83, the highest sensitivity at 0.96, positive predictive value at 0.84, and negative predictive value at 0.96 compared to all indices. For 95% of those successfully extubated, WOB(N)/min was ≤10 J/min.WOB(N)/min had the greatest overall predictive accuracy for extubation compared to traditional indices. WOB(N)/min warrants consideration for use in a complementary manner with spontaneous breathing pattern data for predicting extubation outcome.

Introduction We hypothesized the expiratory time constant (ƬE) may be used to provide real time determinations of inspiratory plateau pressure (Pplt), respiratory system compliance (Crs), and total resistance (respiratory system resistance plus series resistance of endotracheal tube) (Rtot) of patients with respiratory failure using various modes of ventilatory support. Methods Adults (n = 92) with acute respiratory failure were categorized into four groups depending on the mode of ventilatory support ordered by attending physicians, i.e., volume controlled-continuous mandatory ventilation (VC-CMV), volume controlled-synchronized intermittent mandatory ventilation (VC-SIMV), volume control plus (VC+), and pressure support ventilation (PSV). Positive end expiratory pressure as ordered was combined with all aforementioned modes. Pplt, determined by the traditional end inspiratory pause (EIP) method, was combined in equations to determine Crs and Rtot. Following that, the ƬE method was employed, ƬE was estimated from point-by-point measurements of exhaled tidal volume and flow rate, it was then combined in equations to determine Pplt, Crs, and Rtot. Both methods were compared using regression analysis. Results ƬE, ranging from mean values of 0.54 sec to 0.66 sec, was not significantly different among ventilatory modes. The ƬE method was an excellent predictor of Pplt, Crs, and Rtot for various ventilatory modes; r2 values for the relationships of ƬE and EIP methods ranged from 0.94 to 0.99 for Pplt, 0.90 to 0.99 for Crs, and 0.88 to 0.94 for Rtot (P