Int J Emerg Med (2010) 3:105–113 having marked anxiety or requiring some degree of immobilization were carefully evaluated for suitability to be recruited in this pilot study. The suitability of the subjects was evaluated based on the following criteria: 1. All trauma (except head injury) and non-trauma adult patients 2. All adult patients who were able to give verbal and written consent to participate in the study. 3. All patients who were indicated to have procedural sedation. 4. All patients with physical status of ASA I and II Patients were numbered and matched to the drugs under study. Detailed explanations regarding the study and the drugs to be used for PSA were provided to all subjects before getting both verbal and written consent. The explanations given included the effects and the side effects of the drugs under study. Patients also received explan- ations about the procedure that would take place during the PSA. Both verbal and written consents were obtained as required by the University Research Ethical Committee. Standard monitoring (pre-, intra- and post-procedure) of systolic and diastolic blood pressure, heart rate, respiratory rate, end tidal carbon dioxide and O2 saturation were carried out on each patient selected to be in the study (parameters for adverse events). In this study we used nasal prong microstream capnography for monitoring the cardio- respiratory status of patients [11]. The capnographic tubing was attached to a Datascope® monitor manufactured in the USA. The machine was calibrated daily by the same investigator. The vital signs were charted in the case report form every 5 to 10 min despite continuous monitoring of these parameters. All of the selected patients were to be given intravenous normal saline before the procedure at a rate of 500 ml/2 h to avoid the risk of significant hypotension, and this was part of the fasting (nothing by mouth) procedure prior to the procedure. Patients were randomly allocated to one of the two groups: 1. Group A: Subjects received IV fentanyl 1 mcg/kg as a titration dose and propofol 1 mg/kg followed by propofol 0.5 mg/kg if needed (n = 20). 2. Group B: Subjects received IV fentanyl 1 mcg/kg as a bolus dose and a titration dose of midazolam 0.1 mg/kg and 0.1 mg/kg if needed (n =20). A modified Ramsay Scoring System was used to monitor the drug titration to achieve either grade 3 or 4 on the scoring system (Table 1). Vital signs were monitored and recorded every 5–10 min until the procedure ended. Any cardiorespiratory adverse reactions during the proce- dures were closely observed, documented and managed according to departmental guidelines. The specialists, Table 1 Modified Ramsay Scoring System 107 Score 1 2 3 4 5 6 Response Anxious or restless or both Cooperative, orientated and tranquil Responding to commands Brisk response to stimulus Sluggish response to stimulus No response to stimulus residents, medical officers and paramedics in the depart- ment were given adequate briefing about the study. This included the issues related to the subject recruitment criteria, the techniques to be carried out, vital sign monitoring and documentation, and data collection through a series of presentations and group discussions 2 months prior to the commencement of the study. For statistical analysis, the non-parametric test was used due to the small sample size and the non-Gaussian distribution. The Mann-Whitney U test was used to compare the two groups. Results Comparison of demographic and other initial parameters for both groups is shown in Table 2. The senior resident (final year residents) in the Emergency Medicine Department and the specialist emergency physicians performed 75% (n= 30) and 25% (n =10) of the procedures, respectively. None of the patients in either group developed any adverse events during and after the procedures. No significant drops in blood pressure, heart rate, respiratory rate, end tidal CO2 and pulse oximetry were observed during and after the procedures. Even though a few parameters, such as MAP, SBP and DBP, dropped intra-procedure, these values normalized post-procedure, and the changes were statis- tically insignificant within and between the groups (Tables 3 and 4). The end tidal carbon dioxide in the propofol group did not show much variation between the pre- and intra- procedural readings. The means (SD) of pre-procedural and intra-procedural end tidal carbon dioxide were 36.05 (6.57) and 37.80 (4.96), respectively. The post-procedural mean (SD) on the other hand was 36.75 (5.46) with the intra-procedural p value being 0.775. In the midazolam group, the means (SD) of end tidal carbon dioxide both pre- procedure and intra-procedure were 34.45 (7.82) and 35.05 (8.97), respectively (p = 0.775). After the procedure, the mean (SD) of end tidal carbon dioxide was 36.70 (7.20). Similarly, no statistical difference in ETCO2 was found between the two study groups.