Intraosseous Pressure Monitoring in Healthy Volunteers.

STUDY OBJECTIVE: Invasively monitoring blood pressure through the IO device has not been thoroughly demonstrated. This study attempted to establish baseline values of IO pressure in a healthy human population. METHODS: This was a prospective, healthy volunteer, observational study. Participants had two IO devices placed (humerus and tibia), and participant IO pressures, vital signs, and pain scores were monitored for up to 60 minutes. Participants were contacted at 24-hours and 7 days post-testing to assess for adverse events. Summary statistics were calculated for systolic, diastolic, and mean humeral and tibial IO pressure. The ratio of IO to non-invasive blood pressure was calculated, and Bland Altman plots were created. The slope (linear) of the mean humeral and the tibial IO pressures were also calculated. RESULTS: Fifteen subjects were enrolled between April and July 2015. Fourteen of 15 humeral IOs were placed successfully (93.3%) and all 15 of the tibial IOs were placed successfully. Mean tibial systolic, diastolic, and mean IO pressure were 55.8 ± 27.9, 49.3 ± 27.1, and 48.4 ± 29.4 mm Hg, respectively. Humeral systolic, diastolic, and mean IO pressure were 32.9 ± 16.0, 27.4 ± 15.2, and 24.5 ± 14.3 mm Hg. The mean tibial IO pressure was 52.5% ± 32.0% of external cuff pressure ratio. The mean humeral IO pressure was 26.5% ± 15.2% of the external mean blood pressure. The Bland Altman plots showed an inconsistent relationship between the systolic and diastolic cuff pressure and the IO pressures. We observed a 1% per minute decrease in IO pressure from the initial placement until the final reading. CONCLUSIONS: Intraosseous pressure readings can be obtained in healthy human volunteers. However, absolute IOP values were not consistent between subjects. Future research may determine how IO pressure can be used to guide therapy in ill and injured patients.

Comparison of success rates between two video laryngoscope systems used in a prehospital clinical trial.

OBJECTIVES: The primary aims of this study were to compare paramedic success rates and complications of two different video laryngoscopes in a prehospital clinical study. METHODS: This study was a multi-agency, prospective, non-randomized, cross over clinical trial involving paramedics from four different EMS agencies. Following completion of training sessions, six Storz CMAC™ video laryngoscopes and six King Vision™ (KV) video laryngoscopes were divided between agencies and placed into service for 6 months. Paramedics were instructed to use the video laryngoscope for all patients estimated to be ≥ 18 years old who required advanced airway management per standard operating procedure. After 6 months, the devices were crossed over for the final 6 months of the study period. Data collection was completed using a telephone data collection system with a member of the research team (available 24/7). First attempt success, overall success, and success by attempt, were compared between treatment groups using exact logistic regression adjusted for call type and user experience. RESULTS: Over a 12-month period, 107 patients (66 CMAC, 41 KV) were treated with a study device. The CMAC had a significantly higher likelihood of first attempt success (OR = 1.85; 95% CI 0.74, 4.62; p = 0.188), overall success (OR = 7.37; 95% CI 1.73, 11.1; p = 0.002), and success by attempt (OR = 3.38; 95% CI 1.67, 6.8; p = 0.007) compared to KV. Providers reverted to direct laryngoscopy in 80% (27/34) of the video laryngoscope failure cases, with the remaining patients having their airways successfully managed with a supraglottic airway in 3 cases and bag-valve mask in 4 cases. The provider-reported complications were similar and none were statistically different between treatment groups. Complication rates were not statistically different between devices. CONCLUSION: The CMAC had a higher likelihood of successful intubation compared to the King Vision. Complication rates were not statistically different between groups. Video laryngoscope placement success rates were not higher than our historical direct laryngoscopy success rates.

Supraglottic airway device use as a primary airway during rapid sequence intubation.

INTRODUCTION: This study compared first-attempt placement success rates of the King LTS-D as a primary airway for patients requiring medication-assisted airway management (MAAM) against historical controls. SETTING: Rotor-wing division of a single critical care transportation company METHODS: 53 providers (RNs/EMT-P) consented to participation and were trained in the use of the King LTS-D. All patients in need of MAAM per agency treatment guidelines were screened for inclusion and exclusion criteria. After each placement attempt, providers completed data collection via telephone. The primary endpoint was comparison of first-attempt placement success rate between the King LTS-D and historical control endotracheal intubation (ETI) MAAM patients. Overall placement success, time to placement, pre- and post-placement SaO2, ETCO2 at 2 minutes after placement, and complications were also analyzed. RESULTS: 38 patients received rapid sequence intubation with the King LTS-D by 23 of 58 consented providers. First-attempt success rate was 76% (29/38), with an overall success rate of 84% (32/38). The primary endpoint analysis showed no difference in first-attempt success rate between historical control ETI MAAM data and King LTS-D (71% vs 76%; OR = 0.1.34 [95% CI Intubation time to insertion was 26 seconds (IQR = 12-46). Pre- and post-insertion SaO(1)2 values were 88.9 ± 12.6% and 92.1 ± 12.7%, respectively. Mean ETCO2 at 2 minutes after placement was 34.8 ± 4.0. Vomit in the patient's airway was the most frequently reported complication (46%). CONCLUSION: Success rates with the King LTS-D were not significantly different from historical control ETI data. Time to placement was comparable to previous reports.

The emergency department experience with prehospital ketamine: a case series of 13 patients.

BACKGROUND: There are no published reports examining the effects that ketamine administered prior to hospital arrival has on patients after their transfer to the emergency department (ED). OBJECTIVE: In order to better understand the risk-benefit ratio for the prehospital use of ketamine, we examined the ED courses of 13 patients to whom emergency medical services (EMS) had administered ketamine for chemical restraint. METHODS: This project was undertaken as part of our EMS system's continuous quality improvement (CQI) process. Data were collected retrospectively. All patients who were given ketamine by EMS providers under our medical direction were identified by prehospital care report queries. The treating paramedic and emergency physician were provided a CQI form after disposition of the patient from their care. The data were tabulated and descriptive statistics were calculated. RESULTS: Thirteen patients were given ketamine by EMS providers, with 13 of 13 having EMS records and 12 of 13 having ED records available for review. Time from ketamine administration to peak sedation was <5 minutes in 11 patients and 20 minutes for two patients. On emergency physician examination, five of 12 patients had Richmond Agitation Sedation Scale (RASS) scores of -5 (unarousable), one of 12 had a RASS score of -4 (deep sedation), four of 12 had RASS scores of -3 (moderate sedation), and two of 12 had RASS scores of -2 (light sedation). Three patients developed hypoxia, two in the ED and one prior to hospital arrival. Two of these patients required intubation and one was treated with jaw thrust. Indications for intubation were recurrent laryngospasm and intracranial bleeding. One additional patient experienced a single episode of hypersalivation, which was successfully treated with suctioning of the oropharynx. Of the nonintubated patients, three of 10 were diagnosed with an emergence reaction and five of 10 required additional sedation. The primary diagnosis on ED disposition was drug/ethanol intoxication (3), psychosis (4), intracranial bleeding (1), seizure (1), suicidal ideation (1), agitation (1), and altered mental status (1). Five patients were discharged from the ED, seven were admitted (two to the intensive care unit, four to medicine, and one to psychiatry), and one patient's disposition was unknown. CONCLUSIONS: In this series of 13 patients, ketamine administered by EMS produced moderate or deeper sedation. Respiratory complications included hypoxia, laryngospasm, and hypersalivation. Emergence reactions occurred in 30% of nonintubated patients, but they were successfully treated with small doses of benzodiazepines.

Laryngospasm and hypoxia after intramuscular administration of ketamine to a patient in excited delirium.

An advanced life support emergency medical services (EMS) unit was dispatched with law enforcement to a report of a male patient with a possible overdose and psychiatric emergency. Police restrained the patient and cleared EMS into the scene. The patient was identified as having excited delirium, and ketamine was administered intramuscularly. Sedation was achieved and the patient was transported to the closest hospital. While in the emergency department, the patient developed laryngospasm and hypoxia. The airway obstruction was overcome with bag-valve-mask ventilation. Several minutes later, a second episode of laryngospasm occurred, which again responded to positive-pressure ventilation. At this point the airway was secured with an endotracheal tube. The patient was uneventfully extubated several hours later. This is the first report of laryngospam and hypoxia associated with prehospital administration of intramuscular ketamine to a patient with excited delirium.

Comparison of prehospital insertion success rates and time to insertion between standard endotracheal intubation and a supraglottic airway.

OBJECTIVE: To compare paramedic insertion success rates and time to insertion between standard ETI and a supraglottc airway device (King LTS-D™) in patients needing advanced airway management. METHODS: Between June 2008 and June 2009, consented paramedics from 4 EMS systems performed ETI or placed a King LTS-D according to a predetermined randomization calendar. Data collection occurred following each placement via telephone. Placement success (ability to ventilate to chest rise, absence of gastric sounds, presence of bilateral lung sounds, and when applicable, quantitative end-tidal CO(2) reading) was compared between treatment groups. Time to ventilation (time from airway device in hand ready to place to time of first successful ventilation) was also compared. RESULTS: A total of 213 patients in need of advanced airway management were treated during the study period, with 9 patients excluded from the analysis. The remaining 204 placements by 110 of the 272 consented paramedics were analyzed (median placements per paramedic=1; range=1-7). The overall placement success rate was virtually equal across the two groups (ETI=80.2%, King LTS-D=80.5%; p=0.97). The median time to placement between ETI and the King LTS-D was also not significantly different (ETI=19.5s vs. King LTS-D=20.0s; z=-0.25; p=0.80). CONCLUSION: In this study, no differences in placement success rate or time to insertion were detected between the King LTS-D and ETI.

Use of the King LTS-D during medication-assisted airway management.

OBJECTIVE: This case series evaluated provider use of the King LTS-D as a primary airway in patients requiring rapid-sequence intubation (RSI). METHODS: Twenty-seven paramedics completed a one-hour training session on the use of the device. All patients meeting the service's standard criteria for medication-assisted airway management were included in the study. Following each insertion, paramedics contacted a research hotline to complete data collection. The primary endpoint was successful insertion, with secondary endpoints including time from succinylcholine administration to successful ventilation, pre- and post-insertion vital signs (oxygen saturation [SaO(2)], pulse rate, and systolic and diastolic blood pressure), and end-tidal carbon dioxide [ETCO(2)] value 2 minutes after insertion. Analysis between pre- and postinsertion variables was completed using the Wilcoxon signed-rank test. RESULTS: A total of 11 patients met the enrollment criteria and were treated with the device by nine of the 27 paramedics enrolled in the study. All 11 insertions (100%) were successful, with 10 of the 11 (91%) successes achieved on the first insertion attempt. No significant difference existed between pre- and post-insertion pulse rate or blood pressure measures. A significant difference in SaO(2) values was present (p = 0.007). Median ETCO(2) for the study sample was 40 mmHg (interquartile range [IQR] = 33-46 mmHg). Seventy-three percent (8/11) of patients had a time interval of succinylcholine administration to first ventilation of 1 minute or less (range = 1-3 minutes). One case of aspiration was noted on hospital chart review. CONCLUSION: In this case series, paramedics were able to successfully place and use the King LTS-D in patients meeting our emergency medical services (EMS) system indications for RSI.