Kenneth Deitch

Does End Tidal CO2 Monitoring During Emergency Department Procedural Sedation and Analgesia With Propofol Decrease the Incidence of Hypoxic Events? A Randomized, Controlled Trial

STUDY OBJECTIVE We determine whether the use of capnography is associated with a decreased incidence of hypoxic events than standard monitoring alone during emergency department (ED) sedation with propofol. METHODS Adults underwent ED propofol sedation with standard monitoring (pulse oximetry, cardiac and blood pressure) and capnography and were randomized into a group in which treating physicians had access to the capnography and a blinded group in which they did not. All patients received supplemental oxygen (3 L/minute) and opioids greater than 30 minutes before. Propofol was dosed at 1.0 mg/kg, followed by 0.5 mg/kg as needed. Capnographic and SpO2 data were recorded electronically every 5 seconds. Hypoxia was defined as SpO2 less than 93%; respiratory depression, as end tidal CO2 (ETCO2) greater than 50 mm Hg, ETCO2 change from baseline of 10%, or loss of the waveform. RESULTS One hundred thirty-two subjects were evaluated and included in the final analysis. We observed hypoxia in 17 of 68 (25%) subjects with capnography and 27 of 64 (42%) with blinded capnography (P=.035; difference 17%; 95% confidence interval 1.3% to 33%). Capnography identified all cases of hypoxia before onset (sensitivity 100%; specificity 64%), with the median time from capnographic evidence of respiratory depression to hypoxia 60 seconds (range 5 to 240 seconds). CONCLUSION In adults receiving ED propofol sedation, the addition of capnography to standard monitoring reduced hypoxia and provided advance warning for all hypoxic events.

The Utility of Supplemental Oxygen During Emergency Department Procedural Sedation With Propofol: A Randomized, Controlled Trial

STUDY OBJECTIVE We determine whether supplemental oxygen reduces the incidence of hypoxia by 20% compared with breathing room air in adult study patients receiving propofol for emergency department procedural sedation. METHODS Patients were randomized to receive either supplemental oxygen or compressed air by nasal cannula at 3 L per minute. Physicians were blinded to the gas used and end tidal CO(2) (etco(2)) data. Respiratory depression was defined a priori as oxygen saturation less than or equal to 93%, an etco(2) level of greater than or equal to 50 mm Hg, an absolute etco(2) change from baseline of greater than or equal to 10 mm Hg, or loss of the etco(2) waveform. RESULTS Of the 110 patients analyzed, 56 received supplemental oxygen and 54 received room air. Ten (18%) patients in the supplemental oxygen group and 15 (28%) patients in the compressed air group experienced hypoxia (P=.3, effect size=10%, 95% confidence interval -24% to 7%). Twenty-seven patients (20 supplemental oxygen; 7 room air) met etco(2) criteria for respiratory depression but did not become hypoxic. Physicians identified respiratory depression in 23 of 25 patients who developed hypoxia compared with only 1 of 27 patients who met etco(2) criteria for respiratory depression but who did not have hypoxia. One patient in the supplemental oxygen group experienced a transient arrhythmia and had a short apneic episode, both of which resolved spontaneously. The patient was admitted for observation. CONCLUSION Supplemental oxygen (3 L/minute) trended toward reducing hypoxia in adult study patients; however, the 10% difference observed was not statistically significant and was below our a priori 20% threshold. Blinded capnography frequently identified respiratory depression undetected by the treating physicians.

The utility of high-flow oxygen during emergency department procedural sedation and analgesia with propofol: a randomized, controlled trial.

STUDY OBJECTIVE We determine whether high-flow oxygen reduces the incidence of hypoxia by 20% in adults receiving propofol for emergency department (ED) sedation compared with room air. METHODS We randomized adults to receive 100% oxygen or compressed air at 15 L/minute by nonrebreather mask for 5 minutes before and during propofol procedural sedation. We administered 1.0 mg/kg of propofol, followed by 0.5 mg/kg boluses until the patient was adequately sedated. Physicians and patients were blinded to the gas used. Hypoxia was defined a priori as an oxygen saturation less than 93%; respiratory depression was defined as an end tidal CO(2) greater than 50 mm Hg, a 10% absolute change from baseline, or loss of waveform. RESULTS We noted significantly less hypoxia in the 59 patients receiving high-flow oxygen compared with the 58 receiving compressed air (19% versus 41%; P=.007; difference 23%; 95% confidence interval 6% to 38%). Respiratory depression was similar between groups (51% versus 48%; difference 2%; 95% confidence interval -15% to 22%). We observed 2 adverse events in the high-flow group (1 hypotension, 1 bradycardia) and 2 in the compressed air group (1 assisted ventilation, 1 hypotension). CONCLUSION High-flow oxygen reduces the frequency of hypoxia during ED propofol sedation in adults.

Double-blind, Randomized, Placebo-controlled Study Evaluating the Use of Platelet-rich Plasma Therapy (PRP) for Acute Ankle Sprains in the Emergency Department.

BACKGROUND Over 23,000 people per day require treatment for ankle sprains. Platelet-rich plasma (PRP) is an autologous concentration of platelets that is thought to improve healing by promoting inflammation through growth factor and cytokine release. Studies to date have shown mixed results, with few randomized trials. OBJECTIVES To determine patient function among patients randomized to receive standard therapy plus PRP, compared to patients who receive standard therapy plus sham injection (placebo). METHODS Prospective, randomized, double-blinded, placebo-controlled trial. Patients with severe ankle sprains were randomized. Severity was graded on degree of swelling, ecchymosis, and ability to bear weight. PRP with lidocaine and bupivacaine was injected at the point of maximum tenderness by a blinded physician under ultrasound guidance. The control group was injected in a similar fashion with sterile 0.9% saline. Both groups had visual analog scale (VAS) pain scores and Lower Extremity Functional Scale (LEFS) on days 0, 3, and 8. LEFS and a numeric pain score were obtained via phone call on day 30. All participants were splinted, given crutches, and instructed to not bear weight for 3 days; at this time patients were reevaluated. RESULTS There were 1156 patients screened and 37 were enrolled. Four withdrew before PRP injection was complete; 18 were randomized to PRP and 15 to placebo. There was no statistically significant difference in VAS and LEFS scores between groups. CONCLUSION In this small study, PRP did not provide benefit in either pain control or function over placebo.

The use of inhaled nitrous oxide for analgesia in adult ED patients: a pilot study

BACKGROUND Oligoanalgesia challenges emergency department (ED) health care providers and remains an area of patient dissatisfaction. Nitrous oxide (NO) is a safe, quick-acting, and well-tolerated sedative agent with analgesic and anxiolytic properties that make it ideal for ED use. OBJECTIVES We seek to test the effectiveness of a self-administered and self-contained NO device as an analgesic agent in the ED and assess patient and staff satisfaction with this method. METHODS We enrolled 85 patients 18 years and older in a prospective observational study of patients presenting to the ED with moderate to severe pain (≥30 mm on a 100-mm visual analog scale). Subjects received a mixture of 50% NO via a self-administered portable delivery device. Primary outcome was the reduction in baseline pain scores at 20, 40, and 60 minutes. Secondary outcomes were patient, nurse, and physician satisfaction as reported on a brief satisfaction questionnaire. RESULTS There was a significant reduction in mean pain scores from baseline to 20 minutes that was sustained through the 60-minute period. Most subjects (93%; 95% confidence interval [CI], 85%-97%) and nurses (97%; 95% CI, 90%-99%) reported that the NO delivery system was easy to use and were satisfied with the level of pain relief and would use NO in the future (82%; 95% CI, 73%-89%). Physicians and nurses were also satisfied with the analgesic effects of NO (82%; 95% CI, 73%-89%). CONCLUSIONS The portable NO device is an effective analgesia adjunct for ED patients presenting with painful conditions, and patients, ED nurses, and emergency physicians are satisfied with its use. Nitrous oxide coupled with a nurse-driven analgesia protocol may provide a novel solution for improvement in ED analgesia rates and overall patient satisfaction with ED pain management.

Unrecognized Hypoxia and Respiratory Depression in Emergency Department Patients Sedated For Psychomotor Agitation: Pilot Study

Introduction The incidence of respiratory depression in patients who are chemically sedated in the emergency department (ED) is not well understood. As the drugs used for chemical restraint are respiratory depressants, improving respiratory monitoring practice in the ED may be warranted. The objective of this study is to describe the incidence of respiratory depression in patients chemically sedated for violent behavior and psychomotor agitation in the ED. Methods Adult patients who met eligibility criteria with psychomotor agitation and violent behavior who were chemically sedated were eligible. SpO2 and ETCO2 (end-tidal CO2) was recorded and saved every 5 seconds. Demographic data, history of drug or alcohol abuse, medical and psychiatric history, HR and BP every 5 minutes, any physician intervention for hypoxia or respiratory depression, or adverse events were also recorded. We defined respiratory depression as an ETCO2 of ≥50 mmHg, a change of 10% above or below baseline, or a loss of waveform for ≥15 seconds. Hypoxia was defined as a SpO2 of ≤93% for ≥15 seconds. Results We enrolled 59 patients, and excluded 9 because of ≥35% data loss. Twenty-eight (28/50) patients developed respiratory depression at least once during their chemical restraint (56%, 95% CI 42–69%); the median number of events was 2 (range 1–6). Twenty-one (21/50) patients had at least one hypoxic event during their chemical restraint (42%, 95% CI 29–55%); the median number of events was 2 (range 1–5). Nineteen (19/21) (90%, 95% CI 71–97%) of the patients that developed hypoxia had a corresponding ETCO2 change. Fifteen (15/19) (79%, 95% CI 56–91%) patients who became hypoxic met criteria for respiratory depression before the onset of hypoxia. The sensitivity of ETCO2 to predict the onset of a hypoxic event was 90.48% (95% CI: 68–98%) and specificity 69% (95% CI: 49–84%). Five patients received respiratory interventions from the healthcare team to improve respiration [Airway repositioning: (2), Verbal stimulation: (3)]. Thirty-seven patients had a history of concurrent drug or alcohol abuse and 24 had a concurrent psychiatric history. None of these patients had a major adverse event. Conclusion About half of the patients in this study exhibited respiratory depression. Many of these patients went on to have a hypoxic event, and most of the incidences of hypoxia were preceded by respiratory depression. Few of these events were recognized by their treating physicians.

Linshom respiratory monitoring device: a novel temperature-based respiratory monitor.

PurposeWe sought to develop a temperature-based respiratory instrument to measure respiration noninvasively outside critical care settings.MethodRespiratory temperature profiles were recorded using a temperature-based noninvasive instrument comprised of three rapid responding medical-grade thermistors—two in close proximity to the mouth/nose (sensors) and one remote to the airway (reference). The effect of the gas flow rate on the amplitude of the tracings was determined. The temperature-based instrument, the Linshom Respiratory Monitoring Device (LRMD) was mounted to a face mask and positioned on a mannequin face. Respiratory rates of 5-40 breaths·min−1 were then delivered to the mannequin face in random order using artificial bellows (IngMar Lung Model). Data from the sensors were collected and compared with the bellows rates using least squares linear regression and coefficient of determination. The investigators breathed at fixed rates of 0-60 breaths·min−1 in synchrony with a metronome as their respiratory temperature profiles were recorded from sensors mounted to either a face mask or nasal prongs. The recordings were compared with a contemporaneously recorded sidestream capnogram from a CARESCAPE GEB450 Monitor. The extracted respiratory rates from the LRMD tracings and capnograms were compared using linear regression with a coefficient of determination and a Bland-Altman plot.ResultsThe amplitude of the sensor tracings was independent of the oxygen flow rate. Respiratory rates from the new temperature-based sensor were synchronous and correlated identically with both the artificial bellows (r2 = 0.9997) and the capnometer mounted to both the face mask and nasal prongs (r2 = 0.99; bias = −0.17; 95% confidence interval, −2.15 to 1.8).ConclusionsRespiratory rates using the LRMD, a novel temperature-based respiratory instrument, were consistent with those using capnometry.RésuméObjectifNous avons tenté de mettre au point un instrument respiratoire se fondant sur la température afin de mesurer la respiration de façon non invasive en dehors des unités de soins critiques.MéthodeLes profils de température respiratoire ont été enregistrés à l’aide d’un instrument non invasif se fondant sur la température et composé de trois thermistances de qualité médicale à réponse rapide – deux à proximité de la bouche et du nez (capteurs) et un troisième à l’écart des voies aériennes (référence). L’effet du débit gazeux sur l’amplitude des tracés a été déterminé. L’instrument fondé sur la température, nommément le dispositif de monitorage respiratoire Linshom (LRMD), a été fixé à un masque facial et positionné sur le visage d’un mannequin. Des fréquences respiratoires de 5-40 respirations·min−1 ont ensuite été livrées au visage du mannequin dans un ordre aléatoire à l’aide de soufflets artificiels (modèle de poumon IngMar). Les données des capteurs ont été colligées et comparées aux fréquences des soufflets à l’aide d’une méthode de régression linéaire des moindres carrés et d’un coefficient de détermination. Les chercheurs ont respiré à des fréquences fixes de 0-60 respirations·min−1 en synchronie avec un métronome pendant que leurs profils de température respiratoire étaient enregistrés par des capteurs fixés à un masque facial ou à des canules nasales. Les enregistrements ont été comparés à un tracé de capnogramme latéral enregistré simultanément par un moniteur CARESCAPE GEB450. Les fréquences respiratoires extraites des tracés du LRMD et des capnogrammes ont été comparées à l’aide d’une méthode de régression linéaire avec un coefficient de détermination et un graphique de Bland-Altman.RésultatsL’amplitude des tracés des capteurs était indépendante du débit d’oxygène. Les fréquences respiratoires du nouveau capteur basé sur la température étaient synchrones et identiquement corrélées aux soufflets artificiels (r2 = 0,9997) et au capnomètre fixé au masque facial et aux canules nasales (r2 = 0,99; biais = −0,17; intervalle de confiance 95 %, −2,15 à 1,8).ConclusionLes fréquences respiratoires mesurées à l’aide du LRMD, un nouvel instrument respiratoire fondé sur la température, étaient cohérentes à celles mesurées par capnométrie.

A modified goldfrank sniffing bar improves accuracy in identifying simulated toxins in a case-based teaching model

ObjectiveTo determine if olfactory analysis of toxin proxies aid in the identification of poisons when compared to case histories alone. Methods: A convenience sample of 42 emergency medicine residents participated in a prospective single-blind observational study using a sniffing bar designed with the technique described by Goldfrank et.al. Each subject received 12 written cases describing a patient with a chemical exposure. Ten chemicals with odors corresponding to a specific case history and 2 chemical case controls with no odor comprised the sniffing bar. Each subject was asked to identify the toxin first by reading the case history alone, then again after smelling the corresponding odor. All subjects were asked to record their level of confidence for each case before and after the addition of the sniffing bar using a 5-point Likert scale. Percentages correct before and after the sniffing bar intervention were calculated and two-tailed p-values and 95% confidence intervals were measured. Continuous comparative variables such as the means of the Likert scale confidence measurements were analyzed with the two-tailedt-test. Results: Median percentage of toxins correctly identified was 64.3% (range 9.5–97.6) when based on case description alone and 86.9% (range 9.5–95.2) with addition of the sniffing bar. The percentage of initially incorrect identification reversed after additional data provided by the sniffing bar was 11.5% (range 0–14). Of the 10 actual toxins, correct identification of 6 achieved statistical significance after introduction of the sniffing bar (p = 0.0017; 95% CI 4.6–11.4). There was no association between level of training and improved accuracy with use of the sniffing bar, and overall confidence did not improve significantly after addition of the sniffing bar. Conclusion: Diagnostic accuracy of poisons in case-based scenarios is improved with the use of a sniffing bar. The sniffing bar is a useful adjunct to a traditional case-based emergency medicine toxicology teaching curriculum.