Epidemiology of mechanical ventilation in Argentina. The EpVAr multicenter observational study

OBJETIVE

To describe mechanical ventilation (MV) practices in Argentina, and to explore factors associated with ICU mortality in this population.

DESIGN

A prospective, multicenter, observational study was carried out.

SETTING

Intensive Care.

PATIENTS

We enrolled patients above 18 years old admitted to any of the participating ICUs requiring invasive MV for at least 12 h since the admission to the healthcare institution, including MV initiation in emergency department, operating room or other hospitals.

INTERVENTIONS

None.

VARIABLES

All variables were classified into three categories: variables related to demographic and clinical factors before the MV, factors related to the first day on MV, and factors related to events happening during the MV (complications and weaning from MV). Mechanical ventilation weaning and mortality were classified according to WIND.

RESULTS

The primary analysis included 950 patients. The main indication for MV was acute respiratory failure (58% of patients). Initial ventilation mode was volume control-continuous mandatory ventilation in 75% of cases. ICU and hospital mortality were 44.6% and 47.9% respectively. The variables identified as independent predictors of mortality in ICU were age (OR 3.48 IC 95% 1.22-11.66; p = 0.028), failure to implement NIV before MV (OR 2.76 IC 95% 1.02-7.10; p = 0.038), diagnosis of sepsis (OR 2.46 IC 95% 1.09-5.47; p = 0.027) and extubation failure (OR 4.50 IC 95% 2.05-9.90; p < 0.001).

CONCLUSIONS

The present study allowed us to describe the characteristics and clinical course of the patients who received mechanical ventilation in Argentina, finding as the main result that mortality was higher than that reported in international studies.

Mechanical ventilation in critically-ill pregnant women: a case series

BACKGROUND

Approximately 0.1-0.2% of pregnancies are complicated by respiratory failure requiring mechanical ventilatory support, but few data exist to inform clinical management. This study aimed to characterize current practice and the effect of delivery on respiratory function.

METHODS

A retrospective review was performed of pregnant women who received mechanical ventilation for more than 24h, from four intensive care units in institutions with large-volume obstetric units.

RESULTS

Data were collected from 29 patients with a mean gestation at intensive care unit admission of 25.3 ± 6 weeks. Tidal volumes were 7.7 ± 1.7 mL/kg predicted body weight. Estimated respiratory system compliance was reduced, but was higher in four patients ventilated for neurological conditions without lung disease. Three maternal and three neonatal deaths occurred. Ten patients delivered while on ventilatory support: one spontaneous delivery, four for obstetric indications and five for worsening maternal condition. Following delivery of these 10 patients, three demonstrated a greater than 50% decrease in oxygenation index and five a greater than 50% increase in compliance. No characteristics identified which patients may benefit from delivery.

CONCLUSIONS

Review of current practice in four centers suggests that mechanical ventilation in pregnant patients follows usual guidelines applicable to non-pregnant patients. Delivery was associated with modest improvement in maternal respiratory function in some patients. Any potential benefit of delivery in improving maternal physiology must be weighed against the stress of delivery. The risks of premature birth for the fetus must be weighed against continued exposure to maternal hypoxemia and hypotension.