Lipid emulsion for the treatment of acute organophosphate poisoning: an Open-Label randomized trial

Abstract

Introduction

Many organophosphate (OP) pesticides are lipid-soluble; therefore, intravenous lipid emulsion (ILE) has been evaluated as a possible treatment for acute poisoning. A single bolus dose of 100 ml of 20% ILE was found safe in a pilot observational study. This randomized trial aimed to assess the effectiveness and safety of an extended dose of ILE in acute OP poisoning.

Methods

This was an investigator-initiated, parallel-group, open-label, randomized controlled trial conducted at PGIMER, Chandigarh (India), from January 2019 to June 2020, in patients aged above 13 years with acute OP poisoning. The primary efficacy outcome was to study the change in atropine dose requirement (total and over the first 24 h) for cholinergic crisis after giving an initial bolus dose of 100 ml of 20% ILE followed by an infusion of 100 ml of 20% ILE over 6 h in addition to the standard care. The secondary efficacy outcomes were to detect the effects on hemodynamic variables, length of hospital stay, and duration of mechanical ventilation required. The incidence of adverse events was evaluated.

Results

A total of 45 patients were assigned to receive either ILE (intervention group, n = 23) or normal saline (control group, n = 22) in addition to standard treatment. Baseline variables in both groups were comparable. The median dose of atropine (in mg) in the first 24 h and at complete resolution in the ILE group were similar to the control group (124.0 versus 141.8, p-value 0.916; and 150.8 versus 175.0, p-value 0.935). Hemodynamic variables (systolic and diastolic blood pressures, mean arterial pressure, and pulse rate) over 24, 48, and 72 h of treatment, length of hospital stay, and duration of mechanical ventilation were also unaffected by ILE. Case fatality was 4 and not statistically different between intervention and control groups (1 versus 3, p-value 0.346). There was no excessive fever, dyspnea, elevation of serum amylase, or pancreatitis from ILE.

Conclusion

ILE has no apparent benefit in acute OP poisoning. However, an extended dose appears safe for the indication.

Keywords:

• Organophosphate
• pesticide
• poisoning
• lipid emulsion
• fat emulsion

Acknowledgment

The authors thank Mrs. Sunaina Verma for help in statistics.

Disclosure statement

No potential conflict of interest was reported by the authors.