Israel Medical Association Journal

Background: Prognostication is complex in patients critically ill with coronavirus disease 2019 (COVID-19).

Objectives: To describe the natural history of ventilated critical COVID-19 patients.

Methods: Due to our legal milieu, active withdrawal of care is not permitted, providing an opportunity to examine the natural history of ventilated critical COVID-19 patients. This retrospective cohort included COVID-19 ICU patients who required mechanical ventilation. Respiratory and laboratory parameters were followed from initiation of mechanical ventilation for 14 days or until extubation, death or tracheostomy.

Results: A total of 112 patients were included in the analysis. Surviving patients were younger than non-survivors (62 years [range 54–69] vs. 66 years [range 62–71], P = 0.01). Survivors had a shorter time to intubation, shorter ventilation duration, and longer hospital stay. Respiratory parameters at intubation were not predictive of mortality. Nevertheless, on ventilation day 10, many of the ventilatory parameters were significantly better in survivors. Regarding laboratory parameters, neutrophil counts were significantly higher in non-survivors on day 1 and C-reactive protein levels were significantly lower in survivors on day 10. Modeling using a generalized estimating equation showed small dynamic differences in ventilatory parameters predictive of survival.

Conclusions: In ventilated COVID-19 patients when there is no active care withdrawal, prognostication may be possible after a week; however, differences between survivors and non-survivors remain small.

Background: The use of a high flow nasal cannula (HFNC) was examined for different clinical indications in the critically ill.

Objectives: To describe a single center experience with HFNC in post-extubation critical care patients by using clinical indices.

Methods: In this single center study, the authors retrospectively evaluated the outcome of patients who were connected to the HFNC after their extubation in the intensive care unit (ICU). At 48 hours after the extubation, the patients were divided into three groups: the group weaned from HFNC, the ongoing HFNC group, and the already intubated group.

Results: Of the 80 patients who were included, 42 patients were without HFNC support at 48 hours after extubation, 22 and 16 patients were with ongoing HFNC support and already intubated by this time frame, respectively. The mean ROX index (the ratio of SpO₂ divided by fraction of inspired oxygen to respiratory rate) at 6 hours of the weaned group was 12.3 versus 9.3 in the ongoing HFNC group, and 8.5 in the reintubated group (P = 0.02). The groups were significantly different by the ICU length of stay, tracheostomy rate, and mortality.

Conclusions: Among patients treated with HFNC post-extubation of those who had a higher ROX index were less likely to undergo reintubation.

Background: Enoxaparin is frequently used as prophylaxis for deep venous thrombosis in critically ill patients. 

Objectives: To evaluate three enoxaparin prophylactic regimens in critical care patients with and without administration of a vasopressor.

Methods: Patients admitted to intensive care units (general and post-cardiothoracic surgery) without renal failure received, once daily, a subcutaneous fixed dose of 40 mg enoxaparin, a subcutaneous dose of 0.5 mg/kg enoxaparin, or an intravenous dose of 0.5 mg/kg enoxaparin. Over 5 days anti-activated factor X levels were collected before the daily administration and 4 hours after the injection.

Results: Overall, 16 patients received the subcutaneous fixed dose, 15 received the subcutaneous weight-based dosage, and 8 received the dose intravenously. Around two-fifths (38%) of the patients received vasopressors. There was no difference between anti-activated factor X levels regarding vasopressor administration. However, in all three groups the levels were outside the recommended range of 0.1 IU/ml and 0.3 IU/ml.

Conclusions: Although not influenced by vasopressor administration, the enoxaparin regimens resulted in blood activity levels outside the recommended range.