Extubating to Noninvasive Ventilation: Noninvasive Ventilation from Intensive Care Unit to Home.

Weaning to noninvasive ventilation in intensive care unit and bridging the patients to home with respiratory support is evolving as the technology of noninvasive ventilation is improving. In patients with chronic obstructive pulmonary disease exacerbation, timing of initiation of noninvasive ventilation is the key, as persistently hypercapnic patients show benefits. High-intensity pressure support seems to do better in comparison to low-intensity pressure support. In patients with obesity and hypercapnia, obesity hypoventilation cannot be ruled out especially in an inpatient setting, and it is crucial that these patients are discharged with noninvasive ventilation.

Pulmonary hypertension in metastatic breast cancer: a case of pulmonary tumour thrombotic microangiopathy.

Pulmonary tumour thrombotic microangiopathy (PTTM) and pulmonary tumour emboli (PTE) are distinct but related complications of malignancy. The incidence of each is exceedingly rare, unfortunately often being diagnosed postmortem. Patients with PTTM and PTE typically present with dyspnoea associated with a rapid onset of hypoxia due to pulmonary hypertension (PH), and respiratory failure that is almost certain to be fatal. The prognosis is grim due to the rapidity of the clinical decline and difficulty in establishing an ante-mortem diagnosis. We present a case of new-onset severe PH in a young woman with a recently discovered breast mass. She presented with shortness of breath and experienced rapid deterioration of her cardiopulmonary status which we attributed to PTTM. With early initiation of chemotherapy, systemic steroids and sildenafil, the patient dramatically improved. Case reports have identified early use of steroids, phosphodiesterase inhibitors and other alternative therapies as providing possible benefit in PTTM.

The role of inbreeding depression and mating system in the evolution of heterostyly.

We investigated the role of morph-based differences in the expression of inbreeding depression in loss of the mid-styled morph from populations of tristylous Oxalis alpina. The extent of self-compatibility (SC) of reproductive morphs, the degree of self-fertilization, and the magnitude of inbreeding depression were investigated in three populations of O. alpina differing in their tristylous incompatibility relationships. All three populations exhibited significant inbreeding depression. In two populations with highly modified tristylous incompatibility, manifested as increased reciprocal compatibility between short- and long-styled morphs, substantial SC and self-fertilization of mid-styled morphs were detected, and expected to result in expression of inbreeding depression in the progeny of mid-styled morphs in the natural populations. In contrast, significant self-fertility of the mid-styled morph was absent from the population with typical tristylous incompatibility, and no self-fertilization could be detected. Although self-fertilization and expression of inbreeding depression should result in selection against the mid-styled morph in the later stages of the transition from tristyly to distyly, in O. alpina selection against the mid-styled morph in the early phases of the evolution of distyly is likely due to genic selection against mid-alleles associated with modified tristylous incompatibility, rather than expression of inbreeding depression.