Mechanical ventilation patterns and trends over 20 years in an Israeli hospital system: policy ramifications

Mechanical ventilation is a life supporting modality increasingly utilized when caring for severely ill patients. Its increasing use has extended the survival of the critically ill leading to increasing healthcare expenditures. We examined changes in the hospital-wide use of mechanical ventilation over 20 years (1997-2016) in two Israeli hospitals to determine whether there were specific patterns (e.g. seasonality, weekday vs. weekend) and trends (e.g. increases or decreases) among various hospital departments and units.

Retrospective analysis of prospectively collected data on all mechanically ventilated patients over 20-years in a two-hospital Israeli medical system was performed. Data were collected for each hospital unit caring for ventilated patients. Time-series analysis examined short and long-term trends, seasonality and intra-week variation.

Over two decades overall ventilator-days increased from 11,164 (31 patients/day) in 1997 to 24,317 (67 patients/day) in 2016 mainly due to more patients ventilated on internal medicine wards (1997: 4 patients/day; 2016: 24 patients/day). The increases in other hospital areas did not approach the magnitude of the internal medicine wards increases. Ventilation on wards reflected the insufficient number of ICU beds in Israel. A detailed snapshot over 4 months of patients ventilated on internal medicine wards (n = 745) showed that they tended to be elderly (median age 75 years) and that 24% were ventilated for more than a week. Hospital-wide ventilation patterns were the weighted sum of the various individual patient units with the most noticeable pattern being peak winter prevalence on the internal medical wards and in the emergency department. This seasonality is not surprising, given the greater incidence of respiratory ailments in winter.

Increased mechanical ventilation plus seasonality have budgetary, operational and staffing consequences for individual hospitals and the entire healthcare system. The Israeli healthcare leadership needs to plan and support expanding, equipping and staffing acute and chronic care units that are staffed by providers trained to care for such complex patients.