Monitoring and Management of Fibrodysplasia Ossificans Progressiva: Current Perspectives.

Fibrodysplasia ossificans progressiva (FOP), sometimes known as myositis ossificans progressiva, is an ultra-rare disease in which bone is formed in muscular tissue, tendons and ligaments. This is known as heterotopic ossification (HO). FOP is caused by a heterozygous mutation in the highly conserved ACVR1/ALK2 gene which affects about 1 in 1.5-2 million individuals. At birth, patients with the predominant R206H mutation only exhibit a bilateral hallux valgus. During childhood, heterotopic bone formation develops in a typical pattern, affecting the axial muscles first before appendicular body parts are involved. HO can start spontaneously but is often elicited by soft tissue trauma or medical procedures. After soft tissue injury, an inflammatory process called a flare-up can start, followed by the formation of HO. HO leads to a limited range of motion, culminating in complete ankylosis of nearly all joints. As a result of HO surrounding the thorax, patients often suffer from thoracic insufficiency syndrome (TIS). TIS is the most common cause of a limited life expectancy for FOP patients, with a median life expectancy of 56 years. Management is focused on preventing soft-tissue injury that can provoke flare-ups. This includes prevention of iatrogenic damage by biopsies, intramuscular injections and surgery. Anti-inflammatory medication is often started when a flare-up occurs but has a poor basis of evidence. Several forms of potential treatment for FOP are being researched in clinical trials. Progression of the disease is monitored using CT and 18F-NaF PET/CT combined with functional assessments. Patients are regularly evaluated for frequently occurring complications such as restrictive lung disease. Here, we review the current management, monitoring and treatment of FOP.

When Limb Surgery Has Become the Only Life-Saving Therapy in FOP: A Case Report and Systematic Review of the Literature.

Fibrodysplasia ossificans progressiva (FOP) is a rare disease in which heterotopic ossification (HO) is formed in muscles, tendons and ligaments. Traumatic events, including surgery, are discouraged as this is known to trigger a flare-up with risk of subsequent HO. Anesthetic management for patients with FOP is challenging. Cervical spine fusion, ankylosis of the temporomandibular joints, thoracic insufficiency syndrome, restrictive chest wall disease, and sensitivity to oral trauma complicate airway management and anesthesia and pose life-threatening risks. We report a patient with FOP suffering from life-threatening antibiotic resistant bacterial infected ulcers of the right lower leg and foot. The anesthetic, surgical and postoperative challenges and considerations are discussed. In addition, the literature on limb surgeries of FOP patients is systemically reviewed. The 44 year-old female patient was scheduled for a through-knee amputation. Airway and pulmonary evaluation elicited severe abnormalities, rendering standard general anesthesia a rather complication-prone approach in this patient. Thus, regional anesthesia, supplemented with intravenous analgosedation and N2O-inhalation were performed in this case. The surgery itself was securely planned to avoid any unnecessary tissue damage. Postoperatively the patient was closely monitored for FOP activity by ultrasound and [18F]PET/CT-scan. One year after surgery, a non-significant amount of HO had formed at the operated site. The systematic review revealed seventeen articles in which thirty-two limb surgeries in FOP patients were described. HO reoccurrence was described in 90% of the cases. Clinical improvement due to improved mobility of the operated joint was noted in 16% of the cases. It should be noted, though, that follow-up time was limited and no or inadequate imaging modalities were used to follow-up in the majority of these cases. To conclude, if medically urgent, limb surgery in FOP is possible even when general anesthesia is not preferred. The procedure should be well-planned, alternative techniques or procedures should be tested prior to surgery and special attention should be paid to the correct positioning of the patient. According to the literature recurrent HO should be expected after surgery of a limb, even though it was limited in the case described.

Collaboration Around Rare Bone Diseases Leads to the Unique Organizational Incentive of the Amsterdam Bone Center.

In the field of rare bone diseases in particular, a broad care team of specialists embedded in multidisciplinary clinical and research environment is essential to generate new therapeutic solutions and approaches to care. Collaboration among clinical and research departments within a University Medical Center is often difficult to establish, and may be hindered by competition and non-equivalent cooperation inherent in a hierarchical structure. Here we describe the "collaborative organizational model" of the Amsterdam Bone Center (ABC), which emerged from and benefited the rare bone disease team. This team is often confronted with pathologically complex and under-investigated diseases. We describe the benefits of this model that still guarantees the autonomy of each team member, but combines and focuses our collective expertise on a clear shared goal, enabling us to capture synergistic and innovative opportunities for the patient, while avoiding self-interest and possible harmful competition.

Criteria for cancelling helicopter emergency medical services (HEMS) dispatches.

INTRODUCTION: In The Netherlands there is no consensus about criteria for cancelling helicopter emergency medical services (HEMS) dispatches. This study assessed the ability of the primary HEMS dispatch criteria to identify major trauma patients. The predictive power of other early prehospital parameters was evaluated to design a safe triage model for HEMS dispatch cancellations. METHODS: All trauma-related dispatches of HEMS during a period of 6 months were included. Data concerning prehospital information and inhospital treatment were collected. Patients were divided into two groups (major and minor trauma) according to the following criteria: injury severity score 16 or greater, emergency intervention, intensive care unit admission, or inhospital death. Logistic regression analysis was used to design a prediction model for the early identification of major trauma patients. RESULTS: In total, 420 trauma-related dispatches were evaluated, of which 155 concerned major trauma patients. HEMS was more often cancelled for minor trauma patients than for major trauma patients (57.7% vs 20.6%). Overall, HEMS dispatch criteria had a sensitivity of 87.7% and a specificity of 45.3% for identifying major trauma patients. Significant differences were found for vital sign abnormalities, anatomical components and several parameters of the mechanism of injury. A triage model designed for cancelling HEMS correctly identified major trauma patients (sensitivity 99.4%). CONCLUSION: The accuracy of the current HEMS dispatch criteria is relatively low, resulting in high cancellation rates and low predictability for major trauma. The new HEMS cancellation triage model identified all major trauma patients with an acceptable overtriage and will probably reduce unjustified HEMS dispatches.

Is a maximum Revised Trauma Score a safe triage tool for Helicopter Emergency Medical Services cancellations?

INTRODUCTION: The Revised Trauma Score is used worldwide in the prehospital setting and provides a snapshot of patient's physiological state. Several studies have shown that the reliability of the RTS is high in trauma outcomes. In the Netherlands, Helicopter Emergency Medical Services (HEMS) are mostly used for delivery of specialized trauma teams on-scene and occasionally for patient transportation. In our trauma system, the Emergency Medical Services crew performs triage after arrival on-scene and cancels the HEMS-dispatch if deemed unnecessary. In this study we assessed the ability of a maximum on-scene Revised Trauma Score (RTS=12) to be used as a triage tool for HEMS cancellation. METHODS: All patients with a maximum on-scene RTS after blunt trauma (with or without receiving HEMS care) who were presented in the trauma resuscitation room of two Level-1 trauma centers during a period of 6 months, were included. Information concerning prehospital and in-hospital vital parameters, severity and localization of the injuries, and the in-hospital course were analyzed. Major trauma patients were classified using the following parameters: Injury Severity Score of at least 16, emergency intervention, Intensive Care Unit admission, and in-hospital death. RESULTS: Four-hundred and forty blunt trauma patients having a maximum RTS were included between 1 July and 31 December 2006. Eighty patients received on-scene HEMS care. Almost 16% of the total population concerned major trauma patients, of which only 25 (36%) received HEMS care. In 17 patients (3.9%), the RTS deteriorated during transportation. Major trauma patients sustained more injuries to the chest, abdomen, and lower extremities. CONCLUSION: The RTS alone is not a reliable triage tool for HEMS cancellations in our trauma system and will lead to a considerable rate of undertriage with one in every six cancellations being incorrect. Other criteria based on patient's vital signs, combined with anatomical and mechanism of injury parameters should be developed to safely minimize triage errors.

Cancellations of (helicopter-transported) mobile medical team dispatches in the Netherlands.

BACKGROUND: The trauma centre of the Trauma Center Region North-West Netherlands (TRNWN) has consensus criteria for Mobile Medical Team (MMT) scene dispatch. The MMT can be dispatched by the EMS-dispatch centre or by the on-scene ambulance crew and is transported by helicopter or ground transport. Although much attention has been paid to improve the dispatch criteria, the MMT is often cancelled after being dispatched. The aim of this study was to assess the cancellation rate and the noncompliant dispatches of our MMT and to identify factors associated with this form of primary overtriage. METHODS: By retrospective analysis of all MMT dispatches in the period from 1 July 2006 till 31 December 2006 using chart review, we conducted a consecutive case review of 605 dispatches. Four hundred and sixty seven of these were included for our study, collecting data related to prehospital triage, patient's condition on-scene and hospital course. RESULTS: Average age was 35.9 years; the majority of the patients were male (65.3%). Four hundred and thirty patients were victims of trauma, sustaining injuries in most cases from blunt trauma (89.3%). After being dispatched, the MMT was cancelled 203 times (43.5%). Statistically significant differences between assists and cancellations were found for overall mortality, mean RTS, GCS and ISS, mean hospitalization, length and amount of ICU admissions (p < 0.001). All dispatches were evaluated by using the MMT-dispatch criteria and mission appropriateness criteria. Almost 26% of all dispatches were neither appropriate, nor met the dispatch criteria. Fourteen missions were appropriate, but did not meet the dispatch criteria. The remaining 318 dispatches had met the dispatch criteria, of which 135 (30.3%) were also appropriate. The calculated additional costs of the cancelled dispatches summed up to a total of 34,448 euro, amounting to 2.2% of the total MMT costs during the study period. CONCLUSION: In our trauma system, the MMT dispatches are involved with high rates of overtriage. After being dispatched, the MMT is cancelled in almost 50% of all cases. We found an undertriage rate of 4%, which we think is acceptable. All cancellations were justified. The additional costs of the cancelled missions were within an acceptable range. According to this study, it seems to be possible to reduce the overtriage rate of the MMT dispatches, without increasing the undertriage rate to non-acceptable levels.