Safety of prehospital intravenous bolus dose nitroglycerin in patients with acute pulmonary edema: A 4-year review.

Background: Intravenous nitrates are a primary therapy for hypertensive congestive heart failure (CHF) with acute pulmonary edema (APE) in the hospital setting. Historically, sublingual nitrates are the mainstay of emergency medical services (EMS) pharmacologic therapy for these patients. We aimed to evaluate the safety of prehospital bolus dose intravenous nitroglycerin in patients with APE. Methods: This is a retrospective evaluation of EMS data between March 15, 2018, and March 15, 2022, where CHF with APE was suspected and bolus-dose intravenous nitroglycerin was administered. Protocol inclusion criteria were hypertension (systolic blood pressure [SBP] >160 mmHg) and acute respiratory distress, with a presumption of decompensated CHF with APE. These patients received 1 mg intravenous nitroglycerin, with the option to repeat once for ongoing distress if the SBP remained >160 mmHg. The primary outcomes were adverse events, defined as hypotension (SBP <90 mmHg), syncope, vomiting, or dysrhythmia. Results: The final analysis included 235 patients. In patients receiving intravenous bolus nitroglycerin, the median (interquartile range [IQR]) initial and final EMS SBP values decreased from 198 mmHg (180-218) to 168 (148-187), respectively. The median (IQR) pulse decreased from 108 (92-125) to 103 (86-119), and the median oxygen saturation increased from 89% (82-95) to 98% (96-99). Three episodes (1.3%) of asymptomatic hypotension occurred, and none required intervention. Conclusion: This study supports a favorable safety profile for prehospital bolus-dose intravenous nitroglycerin for decompensated CHF with APE. Blood pressure, heart rate, and oxygen saturation improvements are also demonstrated. Further, prospective studies are needed to confirm these findings.

Prehospital Intervention Improves Outcomes for Patients Presenting in Atrial Fibrillation with Rapid Ventricular Response.

OBJECTIVE: To compare outcomes of patients presenting to emergency medical services (EMS) with atrial fibrillation with rapid ventricular response (AF-RVR) who did and did not receive prehospital advanced life support (ALS) rate or rhythm control intervention(s). METHODS: This retrospective cohort study used the 2021 ESO Data Collaborative (Austin, TX) dataset. We identified 9-1-1 scene responses for patients aged 16 to 100 years old presenting with AF and an initial heart rate ≥ 110 beats per minute (bpm). Prehospital ALS interventions for AF-RVR included medications (e.g., calcium channel blockers, beta blockers, etc.) or electrical cardioversion. Outcome measures included prehospital rate control (i.e., final prehospital heart rate < 110 bpm), emergency department (ED) discharge to home, ED and hospital length of stay, and mortality. We also evaluated prehospital adverse events-specifically bradycardia, hypotension, and cardiac arrest. We used propensity score matching to compare outcomes among treated and untreated patients with similar demographic and clinical characteristics. We determined the average treatment effect on the treated (ATET) with 95% confidence intervals (CI) and the number needed to treat (NNT). RESULTS: After propensity score matching, prehospital outcomes were available for 4,859 treated patients matched with 4,859 similar untreated patients. Prehospital rate control was more frequent for treated than for untreated patients (41.0% vs. 18.2%, ATET +22.8%, CI: +21.1%; +24.6%, NNT = 5). Hospital outcomes were available for 1,347 treated patients matched with 1,347 similar untreated patients. Treated patients were more likely to be discharged from the ED (37.9% vs. 34.0%, ATET +3.9%, CI: +0.2%; +7.5%, NNT = 26) and less likely to die (4.3% vs. 6.7%, ATET -2.5%, CI: -4.2%; -0.8%, NNT = 40) compared to untreated patients. Hypotension occurred more often in treated patients (ATET +2.6%, CI: +1.5%; +3.7%), but resolved before ED arrival in 73% of affected patients. Otherwise, adverse event rates did not significantly differ for the two groups. CONCLUSIONS: In this propensity score matched study of patients presenting to EMS with AF-RVR, prehospital ALS interventions were associated with more frequent prehospital rate control, more frequent discharge to home from the ED, and lower mortality.

Prehospital use of a modified HEART Pathway and point-of-care troponin to predict cardiovascular events.

CLINICAL TRIAL REGISTRATION: clinicaltrials.gov (NCT02709135).

Improving Prehospital Protocol Adherence Using Bundled Educational Interventions.

BACKGROUND: Seizures and anaphylaxis are life-threatening conditions that require immediate treatment in the prehospital setting. There is variation in treatment of pediatric prehospital patients for both anaphylaxis and seizures. This educational study was done to improve compliance with pediatric prehospital protocols, educate prehospital providers and decrease variation in care. OBJECTIVE: To improve the quality of care for children with seizures and anaphylaxis in the prehospital setting using a bundled, multifaceted educational intervention. METHODS: Evidence-based pediatric prehospital guidelines for seizures and anaphylaxis were used to create a curriculum for the paramedics in the EMS system. The curriculum included in-person training, videos, distribution of decision support tools, and a targeted social media campaign to reinforce the evidence-based guidelines. Prehospital charts were reviewed for pediatric patients with a chief complaint of anaphylaxis or seizures who were transported by paramedics to one of ten hospitals, including three children's hospitals, for 8 months prior to the intervention and eight months following the intervention. The primary outcome for seizures was whether midazolam was given via the preferred intranasal (IN) or intramuscular (IM) routes. The primary outcome for anaphylaxis was whether IM epinephrine was given. RESULTS: A total of 1,402 pediatric patients were transported for seizures by paramedics to during the study period. A total of 88 patients were actively seizing pre-intervention and 93 post-intervention. Of the actively seizing patients, 52 were given midazolam pre-intervention and 62 were given midazolam post-intervention. Pre-intervention, 29% (15/52) of the seizing patients received midazolam via the preferred IM or IN routes, compared to 74% (46/62) of the seizing patients post-intervention. A total of 45 patients with anaphylaxis were transported by paramedics, 30 pre-intervention and 15 post-intervention. Paramedics administered epinephrine to 17% (5/30) patients pre-intervention and 67% (10/15) patients post-intervention. CONCLUSION: The use of a bundled, multifaceted educational intervention including in-person training, decision support tools, and social media improved adherence to updated evidence-based pediatric prehospital protocols.