INTRODUCTION: It is difficult to obtain an accurate blood pressure (BP) measurement, especially in the prehospital environment. It is not known fully how various BP measurement techniques differ from one another. STUDY OBJECTIVE: The study hypothesized that there are differences in the accuracy of various non-invasive blood pressure (NIBP) measurement strategies as compared to the gold standard of intra-arterial (IA) measurement. METHODS: The study enrolled adult intensive care unit (ICU) patients with radial IA catheters placed to measure radial intra-arterial blood pressure (RIBP) as a part of their standard care at a large, urban, tertiary-care Level I trauma center. Systolic blood pressure (SBP) was taken by three different NIBP techniques (oscillometric, auscultated, and palpated) and compared to RIBP measurements. Data were analyzed using the paired t-test with dependent samples to detect differences between RIBP measurements and each NIBP method. The primary outcome was the difference in RIBP and NIBP measurement. There was also a predetermined subgroup analysis based on gender, body mass index (BMI), primary diagnosis requiring IA line placement, and current vasoactive medication use. RESULTS: Forty-four patients were enrolled to detect a predetermined clinically significant difference of 5mmHg in SBP. The patient population was 63.6% male and 36.4% female with an average age of 58.4 years old. The most common primary diagnoses were septic shock (47.7%), stroke (13.6%), and increased intracranial pressure (ICP; 13.6%). Most patients were receiving some form of sedation (63.4%), while 50.0% were receiving vasopressor medication and 31.8% were receiving anti-hypertensive medication. When compared to RIBP values, only the palpated SBP values had a clinically significant difference (9.88mmHg less than RIBP; P < .001). When compared to RIBP, the oscillometric and auscultated SBP readings showed statistically but not clinically significant lower values. The palpated method also showed a clinically significant lower SBP reading than the oscillometric method (5.48mmHg; P < .001) and the auscultated method (5.06mmHg; P < .001). There was no significant difference between the oscillometric and auscultated methods (0.42mmHg; P = .73). CONCLUSION: Overall, NIBPs significantly under-estimated RIBP measurements. Palpated BP measurements were consistently lower than RIBP, which was statistically and clinically significant. These results raise concern about the accuracy of palpated BP and its pervasive use in prehospital care. The data also suggested that auscultated and oscillometric BP may provide similar measurements.

OBJECTIVES: If a patient wishes to refuse treatment in the prehospital setting, prehospital providers and consulting emergency physicians must establish that the patient possesses the capacity to do so. The objective of this study is to assess agreement among prehospital providers and emergency physicians in performing patient capacity assessments. METHODS: This study involved 139 prehospital providers and 28 emergency medicine physicians. Study participants listened to 30 medical control calls pertaining to patient capacity and were asked to interpret whether the patients in the scenarios had the capacity to refuse treatment. Participants also reported their comfort level using modified Likert scales. Inter-rater reliability was calculated utilizing Fleiss' and Model B kappa statistics. Fisher's exact tests were used to calculate p-values comparing the proportion in each cohort that responded "no capacity." Primary outcomes included inter-rater reliability in the physician and prehospital provider cohorts. RESULTS: The inter-rater agreement between the physicians was low (Fleiss' kappa = 0.31, standard error [SE] =0.06; model-based kappa = 0.18, SE = 0.04). Agreement was similarly low for the 135 prehospital providers (Fleiss' kappa = 0.30, SE = 0.06; model-based kappa = 0.28, SE = 0.04). The difference between the proportion of physicians and prehospital providers who responded "no capacity" was statistically significant in five of 30 scenarios. Median prehospital provider and physician confidence, on a 1 to 4 scale, was 2.00 (Q1-Q3 = 1.00-3.00 for prehospital providers and Q1-Q3 =1.0-2.0 for physicians). CONCLUSIONS: There was poor inter-rater reliability in capacity determination between and among the prehospital provider and physician cohorts. This suggests that there is need for additional study and standardization of this task.

OBJECTIVE: The goal of this study is to describe complications and outcomes of prehospital ketamine use for agitation as compared to other methods of physical or chemical restraint such as haloperidol plus benzodiazepine or physical restraint only. METHODS: We conducted a single-center retrospective review of patient encounters in which restraint was administered in the prehospital setting. At the beginning of our study window, only physical restraint was available to paramedics managing agitated patients but subsequently, haloperidol and benzodiazepines were introduced, followed by ketamine 2 years later. By comparing patients before and after each transition, we divided subjects into 3 cohorts based on restraint type: physical restraint, haloperidol plus benzodiazepine, and ketamine. Demographic data were collected, and outcome measures included intubation rate, need for additional physical or chemical restraint, emergency department (ED) length of stay, need for hospital admission, and employee injury. RESULTS: Of 214 subjects included in the study, 95 patients were administered ketamine, 68 received haloperidol and benzodiazepine, and 51 were physically restrained. Eleven of the patients (11.6%) who received ketamine were intubated. Compared to patients who received haloperidol plus benzodiazepine, patients who received ketamine were more likely to be intubated (odds ratio [OR] = 8.77, 95% confidence interval [CI], 1.10-69.68) and were more likely to require additional chemical restraint when compared to haloperidol/benzodiazepine or physical restraint only (OR =2.94, 95% CI, 1.49-5.80, and OR =2.15, 95% CI, 1.07-4.31, respectively). There were no differences between the 2 chemical sedation groups in terms of ED length of stay or hospital admission rate. CONCLUSIONS: This study demonstrates a lower intubation rate in patients administered ketamine than prior literature in association with a lower weight-based dosing regimen. Ketamine use was correlated with a higher frequency of intubation and a greater need for additional chemical restraint when compared with other restraint modalities, though exogenous factors such as provider preference may have impacted this result. There was no difference in ED length of stay or admission rate between the ketamine and haloperidol plus benzodiazepine groups. Further prospective study is needed to determine whether there is a subset of patients for whom ketamine would be beneficial compared to other therapies.