Anesth Analg. 2019 Jul 17;Epub ahead of print

# Oligoanalgesia in Patients With an Initial Glasgow Coma Scale Score ≥8 in a Physician-Staffed Helicopter Emergency Medical Service: A Multicentric Secondary Data Analysis of >100,000 Out-of-Hospital Emergency Missions.

Helm M, Hossfeld B, Braun B, Werner D, Peter L, Kulla M

BACKGROUND: Oligoanalgesia, as well as adverse events related to the initiated pain therapy, is prevalent in out-of-hospital emergency medicine, even when a physician is present. We sought to identify factors involved in insufficient pain therapy of patients presenting with an initial Glasgow Coma Scale (GCS) score of ≥8 in the out-of-hospital phase, when therapy is provided by a physician-staffed helicopter emergency medical service (p-HEMS).

METHODS: This was a multicenter, secondary data analysis of conscious patients treated in primary p-HEMS missions between January 1, 2005, and December 31, 2017. Patients with a numeric rating scale (NRS) pain score ≥4, GCS score ≥8 on the scene, without cardiopulmonary resuscitation (CPR), and a National Advisory Committee for Aeronautics (NACA) score <VI were included. Multivariable logistic binary regression analyses were used to identify characteristics of oligoanalgesia (NRS ≥4 at handover or pain reduction <3). Linear regression analysis was used to identify changes in pain treatment within the study period.

RESULTS: We analyzed data from 106,730 patients (3.6% missing data at variable level). Of these patients, 82.9% received some type of analgesic therapy on scene; 79.1% of all patients received analgesic drugs, and 38.6% received nonpharmacological interventions, while 37.4% received both types of intervention. Oligoanalgesia was identified in 18.4% (95% confidence interval [CI], 18.1-18.6) of patients. Factors associated with oligoanalgesia were a low NACA score and a low NRS score, as well as central nervous system or gynecological/obstetric complaints. The use of weak opioids (odds ratio [OR] = 1.05; 95% CI, 0.68-1.57) had no clinically relevant association with oligoanalgesia, in contrast to the use of strong or moderate opioids, nonopioid analgesics, or ketamine. We observed changes in the analgesic drugs used over the 12-year study period, particularly in the use of strong opioids (fentanyl or sufentanil), from 30.3% to 42.3% (P value <.001). Of all patients, 17.1% (95% CI, 16.9-17.3) did not receive any type of pain therapy.

CONCLUSIONS: In the studied p-HEMS cohort, oligoanalgesia was present in 18.4% of all cases. Special presenting complaints, low NACA scores, and low pain scores were associated with the occurrence of oligoanalgesia. However, 17.1% of patients received no type of pain therapy, which suggests a scope for further improvement in prehospital pain therapy. Pharmacological and nonpharmaceutical pain relief should be initiated whenever indicated.