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International Journal of Emergency Medicine This Provisional PDF corresponds to the article as it appeared upon acceptance. Fully formatted PDF and full text (HTML) versions will be made available soon. Review article: Use of ultrasound in the developing world International Journal of Emergency Medicine 2011, 4:72 doi:10.1186/1865-1380-4-72 Stephanie Sippel (sippel@gmail.com) Krithika Muruganandan (krithika_muruganandan@brown.edu) Adam Levine (adamlevinemd@gmail.com) Sachita Shah (sachita.shah@gmail.com) ISSN Article type 1865-1380 Review Submission date 17 June 2011 Acceptance date 7 December 2011 Publication date 7 December 2011 Article URL http://www.intjem.com/content/4/1/72 This peer-reviewed article was published immediately upon acceptance. It can be downloaded, printed and distributed freely for any purposes (see copyright notice below). Articles in International Journal of Emergency Medicine are listed in PubMed and archived at PubMed Central. 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This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Review article: Use of ultrasound in the developing world Stephanie Sippel1, Krithika Muruganandan*1, Adam Levine1 and Sachita Shah1 1 Department of Emergency Medicine, Brown University, 593 Eddy Street, Providence RI, 02903, USA *Corresponding author: krithika_muruganandan@brown.edu Email addresses: SS: sippel@gmail.com KM: krithika_muruganandan@brown.edu AL: adamlevinemd@gmail.com SS: sachita.shah@gmail.com Abstract As portability and durability improve, bedside, clinician-performed ultrasound is seeing increasing use in rural, underdeveloped parts of the world. Physicians, nurses and medical officers have demonstrated the ability to perform and interpret a large variety of ultrasound exams, and a growing body of literature supports the use of point-of-care ultrasound in developing nations. We review, by region, the existing literature in support of ultrasound use in the developing world and training guidelines currently in use, and highlight indications for emergency ultrasound in the developing world. We suggest future directions for bedside ultrasound use and research to improve diagnostic capacity and patient care in the most remote areas of the globe. Background It is generally accepted that in rural and remote areas of low- and middle-income countries (LMICs) diagnostic imaging is often insufficient, and in some instances completely lacking [1]. Over the past decade, however, the use of clinician-performed, hand-carried, bedside ultrasound has gained increasing popularity as a useful imaging modality worldwide, helping to boost the diagnostic capacity of rural district hospitals in resource-limited settings. The increase in ultrasound services provided by nonradiologists is likely due to several factors, including the increased affordability, availability, portability and durability of ultrasound machines. In addition, machine design has become more user-friendly for novice users with fewer knobs and streamlined design for quick comprehension of key features. Many new laptop-based machines are now in production. Improvements in battery life for hand-carried machines, and the lack of film, chemical developers and dedicated technicians, allow for use of ultrasound in health missions to remote areas of the developing world. Because of this evolution in technology and the growing body of literature to support its use, ultrasound has gained increasing recognition as a valuable diagnostic tool for resource-limited settings by the ministries of health in LMICs, several non-governmental organizations and the World Health Organization (WHO). Experience and prior study There have been a multitude of small studies depicting novel uses of ultrasound in the developing world, but only a few studies have looked at the impact of ultrasound use on clinical management and patient outcomes, and whether ultrasound may be a sustainable modality for use in LMICs. In a study from Rwanda, ultrasound was introduced at two rural district hospitals, and the impact on patient care was assessed by asking providers to identify if ultrasound changed patient management plans. Of the first 345 ultrasounds performed, the majority of scans were performed for obstetrical purposes (102), followed by abdominal (94), cardiac (49), renal (40) and pulmonary (36), along with a few procedural usages, soft tissue and vascular exams. In 43% of patient cases, ultrasound findings changed the initial patient management plan, with the most common changes cited as: performing a surgical procedure, medication changes, clinic referral and canceling of a planned surgical procedure [2]. In another study by Kotlyar et al., ultrasound changed patient management in 62% of cases at the major tertiary care center in Monrovia, Liberia. The greatest impact on patient management was seen with first trimester obstetric ultrasound, followed by FAST, cardiac and second/third trimester ultrasound exams; the smallest impact was seen in RUQ and gynecologic studies [3]. In another study of patients in the Amazon jungle, a group of American emergency physicians found that ultrasound examinations changed treatment in 28% of patients, including appropriate referrals for more definitive care in some cases and avoiding a potentially dangerous 2-day evacuation for additional medical care in others [4]. The consulting physician’s differential diagnosis was narrowed after reviewing the ultrasound results in 72% of cases, with diagnostic certainty achieved in 68% of cases. In 2004, a study by radiologists sought to demonstrate that portable ultrasound could enhance the medical management and clinical outcomes of patient care in a variety of clinical settings (surgeon’s office, hospital operating room and clinics) in the SekondiTakoradi area, Ghana. In clinic settings, the most frequent ultrasound examinations were musculoskeletal (46%), with the remainder being obstetric, pelvic and genitourinary. In the hospital setting, abdominal, pelvic and genitourinary ultrasounds were the most frequent exams done to assess bladder masses, prostate and uterine size, and kidney abnormalities. A total of 67 ultrasound examinations were performed with abnormal findings in 54 (81%). One hundred percent of these abnormal ultrasounds were thought to add to the clinical diagnosis, and 40% (27) influenced the outcome or decision regarding treatment for these patients [5]. Similar results have also been seen in larger studies. In western Cameroon, the Ad Lucem Hospital of Banka-Bafang conducted a retrospective review of 1,119 ultrasound examinations and their effect on diagnosis and treatment. Abnormal findings were present in 78% of the cases, and 67.8% of the ultrasounds were judged to be useful for diagnosis, while only 4% were felt to be noncontributory. Ultrasound provided the diagnosis in 31.6% of the cases, and confirmed a prior diagnosis or allowed a differential diagnosis to be excluded in 36.2% of the cases. In a subpopulation of confirmed diagnosis (via tissue pathology, additional imaging tests, endoscopy, surgical specimen or laboratory diagnosis), approximately half of the diagnoses made by ultrasound had not been previously considered [6]. Despite its limitations, the impact of ultrasound is beginning to become clear, and this tool has become indispensable for the examination of cardiac, abdominal, obstetric, vascular, traumatic and musculoskeletal complaints in the developing world. Given the prevalence of poverty-related diseases, such as tuberculosis, malaria and dehydration due to diarrheal illness, in the developing world, it is no surprise that emerging uses for ultrasound in LMICs include these diseases [7-9]. We summarize here, by region, some of the highlights of diagnostic ultrasound research for specific diseases in resourcelimited settings in LMICs. Africa Egypt Intrauterine growth retardation (IUGR) is a major contributing factor to perinatal mortality and morbidity in developing countries, and ultrasound may play an important role in early identification of pregnant mothers at risk. In 1988, Mahran et al. demonstrated an 11.8% rate of neonatal growth retardation in 828 pregnant women in Cairo, Egypt. In this group, antenatal ultrasound was able to predict 89.7% of these cases, while only 34.7% were predicted by fundal palpation [10]. Gambia In a 2004 study in Gambia, physicians used a hand-held ultrasound to identify high-risk patients with cardiovascular disease and hypertension. Of the 1,997 patients seen, 17% (342) were found to have elevated blood pressure, and all of these patients underwent echocardiography to identify left ventricular hypertrophy, as a marker for those at highest risk of a cardiovascular event. Sixty-five percent of this hypertensive population demonstrated left ventricular hypertrophy by ultrasound and were started on antihypertensive medications. Patients with borderline hypertension also underwent a cardiac ultrasound examination and were started on antihypertensive medications only if they had evidence of left ventricular hypertrophy. Through this screening and the identification of high-risk hypertensive patients, ultrasound enabled a more effective use of limited healthcare resources [11]. Tanzania In a district hospital in Karagwe, Tanzania, ultrasound services were studied to determine the impact on obstetric care. Nurse midwives, trained in basic obstetric ultrasound, were available to perform studies 24 h/day, whereas specialized ultrasonographers performing advanced ultrasound (including fetal biometrics) were only available during daytime hours. Five hundred forty-two patients with suspected abnormal findings were scanned over 1 year. When evaluating for twins, fetal heart rate or fetal positioning, the basic exam performed by the midwives had 100% agreement with the sonographer. Overall, ultrasound aided in the diagnosis of 39% (212) of patients and changed management plans in 22% (121). This study demonstrated that 24-h availability of basic obstetric ultrasonography performed by midlevel providers could be implemented in a rural hospital setting to lessen the workload of a specialist sonographer while improving patient care [12]. Zambia In rural Zambia, 21 midwives participated in a pilot program for focused obstetric ultrasound to determine whether ultrasound skills could be imparted to nurse midwives. Obstetric ultrasound instruction given by ultrasound fellowship-trained emergency physicians included fetal presentation, fetal heart rate, placental location, number of gestations and assessment of gestational age. Over the 6-month training period, 441 ultrasounds were performed, with the main abnormal findings being non-vertex presentation (61%), multiple gestations (24%) and no fetal heart rate (8%). Ultrasound findings prompted a change in the clinical decision-making in 17% of cases. At the 1year follow-up, ultrasound use continued, with an average number of ten ultrasound examinations per week per midwife, and 100% of the midwives reported that ultrasound helped their practice and changed their management [13]. Zambia/Congo In a large retrospective study from the 1990s, abdominal ultrasound was used to define ultrasound findings of HIV through evaluation of 900 HIV-positive adults in the major tertiary referral hospitals of Lubumbashi, Congo, and Lusaka, Zambia. Ultrasound exams were performed by local practitioners for evaluation of various complaints, including pain, fever and organomegaly, and results of these ultrasounds were compared to age and sex-matched HIV-negative patients. Compared to HIV-negative patients, those with AIDS who underwent an ultrasound examination had significantly higher rates of splenomegaly (24% vs. 35%), hepatomegaly (22% vs. 35%), retroperitoneal and mesenteric lymphadenopathy (11% vs. 31%), biliary tract abnormalities, such as gallbladder wall thickening (12% vs. 25%), gut wall thickening (5% vs. 15%) and ascites (9% vs. 22%). The authors concluded that focused abdominal ultrasound in patients with HIV and AIDS can be a useful tool for diagnosing associated complex gastrointestinal pathology [14]. Malawi Uncertainties regarding accurate gestational age may contribute to the difficulty in accurately assessing the role preterm birth plays in neonatal mortality in the developing world. Ultrasound may help to characterize the true magnitude of this public health concern. In a 2005 study, local practitioners performed ultrasound exams on 512 pregnant women prior to 24-week gestation presenting for prenatal care at a rural health center (Namitambo) or hospital (Thyolo) in Malawi, and provided an estimation of their gestational age. In this cohort, 20.3% of mothers delivered prematurely prior to 37 weeks of gestation, and these infants born between 32 and 37 weeks were twice as likely to die as their full-term counterparts (6.9% vs. 3.4%). This study introduces the idea that early obstetric ultrasound may allow for a more accurate assessment of the actual gestational age at the time of birth, thus demonstrating the true prevalence of preterm birth in the developing world [15]. South Africa South African hospitals experience some of the highest trauma volumes in the world, and most have limited imaging capabilities, leading to significant diagnostic and therapeutic challenges. A study at the Ngwelezane Hospital, a busy referral center in rural KwaZuluNatal, South Africa, examined the use of the FAST (focused assessment with sonography in trauma) exam on blunt and penetrating trauma victims. Over a 12-month period, 72 FAST scans were performed (52 for blunt trauma, 20 for penetrating trauma) with 15 positive scans (20.8%). The overall specificity of the FAST scan was 100%, with a sensitivity of 71.4%, but its sensitivity in penetrating trauma alone was much poorer at 62.5%. This study highlights the valuable role FAST scanning can play in the rapid assessment and timely transfer of appropriate trauma patients to referral hospitals [16]. Asia: India The diagnosis of abdominal tuberculosis is often difficult in the developing world due it its vague clinical features, mimicry of other diseases, and expensive/time consuming workup with CT scan and laparotomy. In Uttar Pradesh, India, investigators sought to assess the accuracy of ultrasound for diagnosis of abdominal tuberculosis in symptomatic patients co-infected with HIV. A retrospective review of 2,543 patients evaluated ultrasound use in an antiretroviral clinic. Patients with persistent fever, change in bowel movements, diarrhea or abdominal distention received an ultrasound evaluating Tb-