Ventilator Maintenance During Load Shedding in Pakistan

Pakistan's chronic load shedding presents a unique and life-threatening challenge for ICU departments. Ventilators are life-critical devices — any interruption in power, even for a few seconds, can be catastrophic. This guide covers what every biomedical engineer and ICU manager in Pakistan needs to know.

Understanding the Risk

Modern ventilators have internal battery backup, but most last only 30–60 minutes. When load shedding exceeds this, or when the UPS system fails to switch quickly enough, the ventilator may alarm, cycle off, or deliver incorrect breath parameters — all dangerous outcomes for critically ill patients.

UPS Requirements for ICU Ventilators

Never use a standard offline UPS for ICU ventilators. You need:

• Online UPS (Double Conversion): Provides zero transfer time — the patient never experiences any power interruption


• Capacity: Size the UPS for at least 2 hours of runtime at full load


• Bypass switch: Manual bypass for maintenance without powering down the ventilator


• Monitoring: UPS with remote monitoring so engineering can track battery health

Generator Requirements

Your hospital generator must start within 10 seconds of mains failure. The automatic transfer switch (ATS) must be tested monthly. ICU circuits should be on the first priority load bank of the generator.

Common Ventilator Problems Caused by Power Issues

• Corrupted settings: Sudden power loss can corrupt saved patient settings in older ventilators


• Compressor damage: Voltage spikes on power restoration damage the air compressor motor


• Display failure: LCD screens are particularly vulnerable to voltage spikes


• Flow sensor drift: Power fluctuations cause flow sensors to give inaccurate readings

Preventive Maintenance Schedule for Load Shedding Environments

• Weekly: Test internal battery backup time, check UPS battery status


• Monthly: Test generator ATS switchover, calibrate flow sensors


• Quarterly: Full ventilator preventive maintenance, replace UPS batteries if capacity below 80%

Emergency Protocol

Every ICU must have a written protocol for ventilator power failure:

1. Manual ventilation bag (Ambu bag) must be at every ventilated patient bedside


2. Nurse training on manual ventilation during power failure


3. Engineer on-call 24/7 with defined response time


4. Backup ventilator available in ICU storage