Introduction: How is “administer a fluid bolus” interpreted by paramedics? There is no existing literature describing this practice in the prehospital setting. Paramedic medical directives authorize the administration of Normal Saline 20 ml/kg to hypotensive patients (systolic BP <90). Anecdotally, auditors of Ambulance Call Reports (ACRs) and paramedics report this amount of fluid is rarely administered. The aim of this study was to determine the amount and rate of IV fluid administered by Advanced Care (ACP) and Primary Care (PCP) paramedics when they give an IV ‘fluid bolus’ during an ambulance call. Methods: We conducted a retrospective analysis of iMedic platform, electronic, ACRs (January 01, 2015 to June 30, 2015) from 8 municipal paramedic services that serve an urban and rural population of 1.4 million. ACRs containing a procedure code 351 (intravenous fluid bolus) were identified. A stratified, random sample of 20 cases per paramedic category (ACP and PCP) from each service was generated using a random number table. ACRs were manually searched, data abstracted onto spread sheets, and the results analyzed using descriptive statistics (Wizard ver 1.8.16 for Mac). Results: The initial sample was 220 cases. 25 were excluded for incomplete documentation, leaving 195 cases (ACP 59, PCP 136) for analysis. The mean IV fluid bolus volume delivered was: ACP 414.8 ml (95%CI: 344.2, 485.4), PCP 242.3 ml (95%CI: 210.9, 274.5). The mean rate of infusion was: ACP 22.7 ml/min (95%CI: 17.6, 27.8) PCP 15.7 ml/min (95%CI 13.2,18.1). Percentage of cases where >250 ml was infused: ACP 74.6%, PCP 44.1%. Percentage of cases where at least 10 ml/kg of fluid was given: ACP 17.0%, PCP 2.9%. Percentage of cases reaching the maximum 20 ml/kg of fluid: ACP 0.5%, PCP 0%. IV cannula size: 18G-ACP 57.4%, PCP 33.3%; 20G ACP 37.0%, PCP 56.8; 22G ACP 0.6%, PCP 9.8%. Conclusion: Paramedics rarely gave the amount of IV fluid they were authorized to give to hypotensive patients. On average, Advanced Care Paramedics administered significantly more fluid and gave it significantly faster than Primary Care Paramedics. ACPs were more likely than PCPs to use 18G cannulas and rarely used 22G cannulas whereas PCPs preferred to use 20G IV cannulas. Further training is required to clarify and improve the paramedic practice of IV bolus administration.