Clinical diagnostic accuracy of respiratory failure in critically ill hematopoietic stem cell transplant patients

RATIONALE

Acute respiratory failure (ARF) is a frequent complication following hematopoietic cell transplantation (HCT). We aimed to characterize the etiologies of ARF in patients who died in the intensive care unit following HCT based on autopsy findings. We then evaluated agreement between the clinical and pathologic diagnosis.

METHODS

We performed a chart review of all HCT patients who died and underwent autopsy in our ICU between 2006-2016. We evaluated the presumed clinical diagnosis and confidence in the diagnosis by chart review, the pathologic diagnosis on autopsy, and whether the clinical-pathologic diagnoses were concordant. When there was discordance, we evaluated whether knowledge of the pathology could have changed management.

RESULTS

Thirteen patients underwent autopsy after dying. Infection was the presumed cause in 11/13 cases. The clinical and pathologic diagnoses were concordant in 6/13(46%). In the seven discordant cases (all clinically diagnosed as infection), autopsy revealed two non-infectious inflammatory causes, one post-transplant lymphoproliferative disorder, and three non-bacterial infectious etiology. Pathologic findings may have changed management in 7/13(54%) cases.

CONCLUSIONS

In a subset of HCT-recipients who died from respiratory failure, discordance was frequent between clinical and pathologic diagnoses. The risks and benefits of obtaining tissue to improve our diagnostic accuracy requires further evaluation.

Helmet non-invasive ventilation compared to facemask non-invasive ventilation and high flow nasal cannula in acute respiratory failure: a systematic review and meta-analysis

BACKGROUND

Although small randomised controlled trials (RCTs) and observational studies have examined helmet non-invasive ventilation (NIV), uncertainty remains regarding its role. We conducted a systematic review and meta-analysis to examine the effect of helmet NIV compared to facemask NIV or high flow nasal cannula (HFNC) in acute respiratory failure.

METHODS

We searched multiple databases to identify RCTs and observational studies reporting on at least one of mortality, intubation, ICU length of stay, NIV duration, complications, or comfort with NIV therapy. We assessed study risk of bias (ROB) using the Cochrane ROB tool for RCTs and the Ottawa-Newcastle scale for observational studies and rated certainty of pooled evidence using GRADE.

RESULTS

We separately pooled data from 16 RCTs (n=949) and 8 observational studies (n=396). Compared to facemask NIV, based on low certainty evidence, helmet NIV may reduce mortality (relative risk (RR) 0.56, 95% confidence interval (CI) (0.33 to 0.95)), and intubation (RR 0.35, 95% CI (0.22 to 0.56)) in both hypoxic and hypercapnic respiratory failure but may have no effect on duration of NIV. There was an uncertain effect of helmet on ICU length of stay and development of pressure sores. Data from observational studies was consistent with the foregoing findings but of lower certainty. Based on low and very low certainty data, helmet NIV may reduce intubation compared to HFNC, but its effect on mortality is uncertain.

CONCLUSION

Compared to facemask NIV, helmet NIV may reduce mortality and intubation; however, the effect of helmet compared to HFNC remains uncertain.

Effect of oxidized cellulose on human respiratory mucosa and submucosa and its implications for endoscopic skull-base approaches

BACKGROUND

Regenerated oxidized cellulose (ROC) sheets have gained popularity as an adjunct to a vascularized nasoseptal flap for closure of dural defects after endoscopic endonasal skull-base approaches (EESBS). However, evidence supporting its impact on the healing process is uncertain. This study was performed to evaluate the impact of ROC on the nasal mucosa and assess its effects on tissue pH, structure, and cell viability.

METHODS

In 5 patients, a 1-cm² piece of ROC gauze was placed on the surface of the middle turbinate before it was resected as part of a standard EESBS. Mucosa treated with ROC was separated from untreated mucosa and a histologic examination of structural changes in the respiratory epithelium was performed. To assess the effect of ROC on pH, increasing amounts of ROC were added to culture medium. Nasal fibroblasts viability was assessed in the presence of ROC before and after the pH was neutralized.

RESULTS

Compared with unexposed controls, treated mucosa exhibited a higher incidence of cell necrosis and epithelial cell detachment. When added to Dulbecco's modified Eagle medium, ROC caused a dose-dependent decrease in pH of the medium. Only 1 ± 0.8% of cultured fibroblasts exposed to the ROC-induced acidic medium were alive, whereas 98.25 ± 0.5% of the cells were viable when the pH was neutralized (p < 0.001).

CONCLUSION

ROC applied in vivo to nasal mucosa induced epithelial necrosis likely by diminishing the medium pH, because pH neutralization prevents its effect. The ultimate effect of this material on the healing process is yet to be determined.

[Treatment conditioning variables in elderly patients with acute myeloid leukemia. An institutional experience]

Patients over 60 years old with acute myeloid leukemia (AML) have a worse prognosis due to several factors that determine the therapeutic outcome. The main predictors of mortality in patients with AML reported in the literature were analyzed in our population. The primary objective was to analyze overall survival. The secondary objective was to determine treatment-related mortality, defined as death within eight weeks of starting treatment. It was designed as a retrospective study. A total of 133 treatment naive patients were included, from January 1991 to August 2014. The adjusted analysis showed that the most important variables to determine overall survival were the WBC count = 30 000 at diagnosis [adjusted HR 2.19 (1.06-4.53), p = 0.03)] and the Performance Status (ECOG) 3 or 4 [aHR 4.63 (1.69-12.68), p < 0.001)]. Performance Status 3-4 was the only variable that conditioned treatment related mortality, showing in the univariate analysis an OR 5.44 (CI 1.93-15.28, p < 0.001). It was also the only variable that kept its statistical power in the multivariate analysis adjusted OR (aOR) 12.40 (IC 1.12-137.17, p = 0.04). The inherent poor outcome in elderly patients diagnosed with AML is not fully understood. The best way of assessing these elderly patients should probably include not only age but the best way of assessing these elderly patients should probably include not only age but laboratory, genetic and molecular studies. Especially designed comorbidity and fragility indices should be included, along with functional status. Leukocytosis and poor quality of life were identified as the most powerfull factors for predicting mortality in our study.