The effect of age and clinical circumstances on the outcome of red blood cell transfusion in critically ill patients

Introduction

Whether red blood cell (RBC) transfusion is beneficial remains controversial. In both retrospective and prospective evaluations, transfusion has been associated with adverse, neutral, or protective effects. These varying results likely stem from a complex interplay between transfusion, patient characteristics, and clinical context. The objective was to test whether age, comorbidities, and clinical context modulate the effect of transfusion on survival.

Methods

By using the multiparameter intelligent monitoring in intensive care II database (v. 2.6), a retrospective analysis of 9,809 critically ill patients, we evaluated the effect of RBC transfusion on 30-day and 1-year mortality. Propensity score modeling and logistic regression adjusted for known confounding and assessed the independent effect of transfusion on 30-day and 1-year mortality. Sensitivity analysis was performed by using 3,164 transfused and non-transfused pairs, matched according the previously validated propensity model for RBC transfusion.

Results

RBC transfusion did not affect 30-day or 1-year mortality in the overall cohort. Patients younger than 55 years had increased odds of mortality (OR, 1.71; P < 0.01) with transfusion. Patients older than 75 years had lower odds of 30-day and 1-year mortality (OR, 0.70; P < 0.01) with transfusion. Transfusion was associated with worse outcome among patients undergoing cardiac surgery (OR, 2.1; P < 0.01). The propensity-matched population corroborated findings identified by regression adjustment.

Conclusion

A complex relation exists between RBC transfusion and clinical outcome. Our results show that transfusion is associated with improved outcomes in some cohorts and worse outcome in others, depending on comorbidities and patient characteristics. As such, future investigations and clinical decisions evaluating the value of transfusion should account for variations in baseline characteristics and clinical context.

     

Automated patient-ventilator interaction analysis during neurally adjusted non-invasive ventilation and pressure support ventilation in chronic obstructive pulmonary disease

Introduction

Delivering synchronous assist during non-invasive ventilation (NIV) is challenging with flow- or pressure-controlled ventilators, especially in patients with chronic obstructive pulmonary disease (COPD). Neurally adjusted ventilatory assist (NAVA) uses diaphragm electrical activity (EAdi) to control the ventilator. We evaluated patient-ventilator interaction in patients with COPD during NIV with pressure support ventilation (PSV) and NAVA using a recently introduced automated analysis.

Methods

Twelve COPD patients underwent three 30-minute trials: 1) PSV with dedicated NIV ventilator (NIV-PSV_Vision), 2) PSV with intensive care unit (ICU) ventilator (NIV-PSV_Servo-I), and 3) with NIV-NAVA. EAdi, flow, and airway pressure were recorded. Patient-ventilator interaction was evaluated by comparing airway pressure and EAdi waveforms with automated computer algorithms. The NeuroSync index was calculated as the percentage of timing errors between airway pressure and EAdi.

Results

The NeuroSync index was higher (larger error) for NIV-PSV_Vision (24 (IQR 15 to 30) %) and NIV-PSV_Servo-I (21 (IQR 15 to 26) %) compared to NIV-NAVA (5 (IQR 4 to 7) %; P <0.001). Wasted efforts, trigger delays and cycling-off errors were less with NAVA (P <0.05 for all). The NeuroSync index and the number of wasted efforts were strongly correlated (r² = 0.84), with a drastic increase in wasted efforts after timing errors reach 20%.

Conclusions

In COPD patients, non-invasive NAVA improves patient-ventilator interaction compared to PSV, delivered either by a dedicated or ICU ventilator. The automated analysis of patient-ventilator interaction allowed for an objective detection of patient-ventilator interaction during NIV. In addition, we found that progressive mismatch between neural effort and pneumatic timing is associated with wasted efforts.     

New perspective in the treatment of low rectal cancer: Total rectal resection and coloendoanal anastomosis

PURPOSE: Presently abdominoperineal resection still remains the most diffuse modality of treatment of low rectal cancer. However, a new surgical approach is now available to avoid such a demolitive surgery and a definitive colostomy. METHODS: From March 1990 to March 1993, 58 total rectal resections were performed in 55 patients affected with primary or recurring cancers of the low rectum. As a restorative procedure, a colic J-shaped pouch and a handsewn pouch-endoanal anastomosis was adopted. All of the primary lesions were within 7 cm of the anal verge; in 74 percent the distal tumor margin was located less than 6 cm from the cutaneous edge. RESULTS: Histologic clearance of the rectum cut edge was documented in all cases. Seven patients relapsed locally from 7 to 14 months after surgery and in 3 more cases distant metastases were documented. Postoperative morbidity is low. After colostomy closure in 78 percent of patients, perfect continence was achieved and in 74 percent less than two bowel movements a day were recorded. Fifty patients are presently alive, 46 without evidence of disease. The follow-up ranged from 2 to 37 (median, 13) months. CONCLUSION: This experience, along with data obtained from last year's literature, indicates that a conservative surgical procedure, such as total rectal resection and coloendoanal anastomosis, can be considered a feasible and radical option for treatment of low rectal cancer.     

Role of Beta-Blocker Therapy in Heart Failure and Atrial Fibrillation

Heart failure is a serious disorder associated with substantial morbidity and mortality. Approximately 15-30% patients with systolic heart failure are in atrial fibrillation and the proportion increases with severity of heart failure. Patients with heart failure and atrial fibrillation have worse outcome than those in sinus rhythm. Beta-blockers, together with angiotensin-converting enzymes inhibitors, are the standard therapy in patients with chronic heart failure. Retrospective studies have suggested that despite the improvement in left ventricular systolic function after treatment with beta-blockers, the exercise capacity and symptoms in those heart failure patients with atrial fibrillation was not improved as much as those in sinus rhythm. Moreover, the use of bisoprolol in the Cardiac Insufficiency Bisoprolol Study II, unlike those in sinus rhythm, failed to produce any survival benefit in patients with poor systolic function and atrial fibrillation. It seems that those patients with heart failure and atrial fibrillation may have different response to beta-blocker therapy. Prospective trials to clarify the impact of beta-blocker therapy and the optimal therapeutic strategy in this high-risk group of patients are warranted.     

In Vitro and In Vivo Effects of Gliotoxin, a Fungal Metabolite:

Gliotoxin is a fungal metabolite that has immunosuppressive properties. First, we determined if gliotoxin could inhibit cytokine production from macrophage and colonic epithelial cell lines, as well as whether it inhibited nuclear factor-kappa B in these same cell types. Second, we evaluated whether gliotoxin could reduce dextran sodium sulfate-induced colitis in rats. A disease activity index, myeloperoxidase activity, and cytokine levels were evaluated on either day 7 or 21. In both cell lines, gliotoxin dose dependently inhibited cytokine production and nuclear factor-kappa B. On day 21, gliotoxin significantly reduced disease activity (diarrhea and bloody stools) in rats. On day 7, gliotoxin treatment significantly improved various indices of colitis, including colonic cytokine levels. Decreased food consumption and weight gain was evident with a larger dose of gliotoxin. In summary, gliotoxin, a nuclear factor-kappa B inhibitor, effectively reduced dextran sodium sulfate-induced colitis in rats. However, gliotoxin exhibited a narrow therapeutic to toxicity ratio in these rats.