The present study has been performed after the earthquake that destroyed the city of L‘Aquila (Italy) on April 6th 2009 (see Additional file 1). The consequences of this catastrophic event were immediately evident: 309 deaths, more than 1.500 injured, either rescued or transferred within 12–24 hrs and 65.000 evacuated people. Almost half of the people evacuated have been hosted in 170 tent camps organized around the earthquake areas by the Italian National Civil Defense Service and by volunteers. Up to 3.300 tents have been installed within 48 hours after the disaster; by the end of the second week, the number of tents had increased to 5385, and 100 camp kitchens and 40 Advanced Medical Presidiums (AMPs) and sanitary aids for nursing care had been set up  (see Additional file 2). Tent camps were localized in seven Mixed Operating Centers (MOC) in the area of L’Aquila (see Additional file 3), where about 7.000 volunteers and one thousand doctors and nurses were operating . The reference hospital of the whole area, St. Salvatore Regional Hospital in L’Aquila, had to be evacuated on the morning of April 6th because of severe structural damages; within 8 hours, up to 250 inpatients had to be transferred by ambulances and air-ambulances. The Civil Hospital was replaced by a camp hospital, which has been operating for three months and then replaced by the modular structure of the Department of Civil Defense, built up for the G8-Summit in L’Aquila (July 2009). Victims, relatives and evacuees have been assisted by one hundred psychologists and psychiatrists in the emergency centers.
Advanced medical presidiums (AMPs)
AMP is a medical location similar to an emergency room; it is constituted by a light, pneumatic tent-type structure, provided by the Department of Civil Defense, where voluntary staffs of doctors (2–3 MD/day) and nurses (2–3 NURSES/day) were operating (see Additional file 2). The present staff included healthcare providers with different roles who have been assisting up to 2.412 persons on 8–12 hour duty shifts. The organization of multiple AMPs, as pre-hospital care centers, was the immediate response of healthcare providers to the needs of the population within 3–4 hours after the earthquake in the whole area of L’Aquila. Italian Government Guidelines in case of catastrophic events indicate that AMPs should be activated within 3–4 hours and dismissed within 72 hours after the emergency . In the area of L’Aquila, however, AMPs had been working longer than the three days scheduled, as L’Aquila Civil Hospital was inoperative and other camp- or area-hospitals hospitals were insufficient to meet the needs of the population.
The study was approved by the local Ethical Committee. This observational, retrospective, study was carried out in 4 AMPs in the MOC area of L’Aquila during the five weeks after the 2009 earthquake in Italy (from April 7th to May 11th 2009). Design and inclusion and exclusion criteria of the study are reported in the flow chart in (see flow-chart 1) Five weeks after the disaster was the time interval included in the study as in this period the population living in tent camps was mostly constituted by persons surviving the earthquake. After this period, most of the residents have been transferred in residential and lodging houses in different cities; meanwhile the number of aid staffs, firefighters, rescue volunteers and workers providing massive support for rubbles removal, rebuilding and clearing of collapsed houses, progressively increased in tent camps.
Selection of participants
A total of 958 triage records of patients attending for the first time an AMPs in the four tent camps (Bazzano, Onna, Paganica, Tempera-S. Biagio) for a total population of 2.412 persons, including 1.777 civilians and 635 volunteers, have been examined. Data have been extrapolated from the census performed in the population living in the camps in that period.
It should be pointed out that during the first 2–4 days after the earthquake the study sample included also persons from other districts, giving a great variability.
Inclusion criteria and data selection are shown in flow-chart 1. Demographic parameters registered for each patient included name, surname, gender, age, general physical conditions. Site and type of trauma and pain intensity (verbal Numerical Rating Scale, v-NRS, that is patients were verbally requested to rate their pain) have also been reported. Previous and/or concomitant pathological conditions, including allergies or addiction to tobacco, alcohol and actual drugs have been registered. Based on anamnestic data and both general and neurological physical examination, the pathologic condition, in particular pain conditions, a diagnostic hypothesis was formulated and a therapeutic intervention prescribed with the attempt to minimize the risk of drug interactions or adverse effects. Painful conditions related to specific causes such as infectious diseases (pharyngitis, laryngitis, gastroenteritis) have not been considered in the present report. Similarly, the prevalence of internal pathologies was not assessed, as only painful syndromes have been taken into consideration. Logistic centers included: Bazzano, Onna, Paganica, Tempera-S. Biagio (see Additional file 3). Data have been collected by clinicians in a registration folder and recorded in personal database.
Patient pain assessment
Pain was quantified by an 11-point numeric scale (v-NRS-11): briefly, adult patients were asked to choose one number on a scale from 0 (no pain) to 10 (severe pain) according to pain intensity . Advantages of this method include easy administration and evaluation, multiple response option, no age-related difficulties or educational barriers in using the scale . Verbal NRS-score recorded in the triage register has been reported in the personal database of the physicians on duty in one of the 4 AMPs only when the main symptom was pain. The clinical and diagnostic evaluation of pain based on the Authors’ experience in pain medicine allowed to provide a qualitative and quantitative analysis of painful conditions in patients in the immediate phases after the natural disaster.
Drugs available in the 4 tent-camps were prescribed by physicians and supplied by healthcare providers of AMP to each patient, every day, during the treatment period. Opioids were kept under lock and registered in order to prevent any abuse and provide a correct therapeutic strategy, considering the shortage and difficult supply of drugs. Immediately after the earthquake, indeed, almost all drugstores were unmanageable, roads were closed and the majority of the population who rushed out of their houses was in the need of drugs for chronic treatment.
Pain management and short-term pain relief
Criteria for pain treatment depended on the clinical characteristics of the painful syndromes and were mostly based on medical history and physical examination either general and neurological. Therapeutic regimens were based on a simplified three steps WHO’ (World Health Organization) pain ladder due to the shortage of medical devices and drugs, in particular opioids .
During the first visit, pain intensity was based on the v-NRS scale and reported in the admission registers for all patients included in the study in addition to signs and symptoms of the painful syndromes. For this scope qualitative characteristics of pain were investigated too: stabbing, burning, paresthesias, allodynia and hyperalgesic signs.
This retrospective analysis included all documents of the first admission to AMPs reporting pain localization, a diagnostic hypothesis, v-NRS-score (T0) and treatment, according to the best clinical practice in pain medicine of the Authors.
Some clinical documents reported the v-NRS-score at admission as well as the v-NRS-score after a very short-term treatment; these parameters have been used to evaluate the immediate effect of drugs (T1 = 1-6 hrs after treatment).
To rationalizing the amount of drugs available, a single dose of a rescue drug and daily doses of drugs used for the initial treatment were provided to the patient.
In our database and admission registers we subsequently searched data of the second evaluation in all patients who returned to our AMPs (T2 = 24 or 48 hours) either because the first drug was ineffective or badly tolerated, or because of relapsing of the pain syndrome or shortage of prescribed drugs.
Also in this case, only clinical documents reporting v-NRS-scores and side effects of drugs were considered; the documents lacking these data were excluded from the analysis. (see flow-chart 2) Based on these data, the efficacy of drug treatment has been evaluated.
Data are presented as means and standard deviations, frequencies are provided as percentages. Prevalence of pain was calculated for the overall population in the first aid centers where the observational study has been carried out.
To minimize bias, sampling was performed during each shift and each day of the week. Frequency was expressed as prevalence with confidence intervals, as the study was performed in 10% of AMPs active during emergency in L’Aquila territory (Bazzano, Onna, Paganica, Tempera-S. Biagio). Confidence intervals of the prevalence in a large sample with high variability allow to estimate the frequency of prevalence in the whole population, with a 95% degree of certainty. The 95% confidence interval was obtained with the following formula, where +/− indicate the upper limit (+) and lower limit (−) interval: P ± 1.96 √P(1-P)/N. Differences in pain score was calculated using Friedman Repeated Measures Analysis of Variance on Ranks and Pairwise Multiple Comparison Test (Tukey Test). P value lower than 0.05 was considered statistically significant. Statistical analysis was performed by SigmaStat® 3.11 Copyright © 2004 Systat Software, Inc.