Introduction: Delegation of controlled medical acts by physicians to paramedics is an important component of the prehospital care framework. Where directives indicate that physician input is needed before proceeding with certain interventions, online medical control (a “patch”) exists to facilitate communication between a paramedic and a Base Hospital Physician (BHP) to request an order to proceed with that intervention. Many factors contribute to success or failure of effective interpersonal communication during a patch call. The aim of this study was to examine areas of potential improvement in communication between paramedics and physicians during the patch call. Methods: Prehospital paramedic calls that included a mandatory patch point (excluding requests for termination of resuscitation and those records which were unavailable) were identified through review of all patch records from January 1, 2014 to December 31, 2017 for Paramedic Services in our region. Written Ambulance Call Reports (ACRs) and audio recordings of paramedic patches were obtained and reviewed. Pre-specified time intervals, clinical factors, specific patch requests and resulting orders from the BHP to the paramedics were extracted. Differences between groups were compared using t-tests. Results: 214 records were initially identified and screened. 91 ACRs and audio patch records were included in the analysis. 51/91 (56%) of patch order requests for interventions were granted by the BHP. Clarification of information provided by the paramedic or reframing of the paramedic's request was required less often, but not statistically significant, in calls ultimately resulting in granted requests versus those that were not granted (mean 1.4 versus 1.7, Δ-0.28; 95% CI -0.75-0.18 p = 0.64). The mean time from first contact with the BHP to statement of the request was similar in patches where the request was granted and not granted (44.9 versus 46.3, Δ-1.4; 95% CI -12.9-10.2, p = 0.49). Conclusion: The communication between BHPs and paramedics is an important and under-investigated component of prehospital emergency care. This retrospective review presents some novel targets for further research and potential education in patch communication to improve efficiency and quality of prehospital care for patients.