Rescue sedation administered to mechanically ventilated patients undergoing interhospital transfer by a South African aeromedical service: A retrospective review

Rescue sedation, defined as the administration of bolus sedation in addition to continuous infusions, has not been previously described in the South African aeromedical setting. The aim was to determine the proportion of patients who received rescue sedation and to describe sedation and analgesic practices during aeromedical transfer. This research was conducted at a single aeromedical service in the Western Cape Province of South Africa. An observational descriptive study of patient care records (PCRs) using a retrospective, cross-sectional design was conducted. All PCRs of mechanically ventilated adults (≥18-years) undergoing aeromedical transfer between June 2019 and June 2024 were eligible for inclusion. Probability sampling in the form of simple random sampling was employed to obtain a representative sample. A total of 158 patients were included. Rescue sedation was administered to 13.9 % ( n = 22/158) of patients (95 % CI 9.2–20). Under-dosed sedation did not increase the odds of RS administration (OR 1.14, 95 % CI 0.5–2.60). The most common rescue sedative administered was ketamine. Use of neuromuscular blocking agents may have increased the odds of RS administration (OR 2.89, 95 % CI 1.33–6.27). Combinations of ketamine and midazolam were used to provide continuous sedation and analgesia in 62.7 % ( n = 99/158) of cases. Syringe drivers were used to administer continuous sedation and analgesia in 89.2 % ( n = 144/158) of cases. Mean doses of ketamine-midazolam combination infusions were 2.3 mg/kg/hr (SD: 0.9) of ketamine and 0.05 mg/kg/hr (SD: 0.03) of midazolam. No sedation depth or pain assessments were documented in PCRs. Rescue sedation may be associated with neuromuscular blocking agents use, with ketamine frequently used for both rescue and continuous sedation and analgesia, often at doses higher than those recommended in local and international guidelines. Notably, no sedation depth or pain assessments were documented, highlighting an important opportunity for quality improvement.