Clinical Signs of Basilar Skull Fracture and Their Predictive Value in Diagnosis of This Injury.

Although clinical signs for the diagnosis of basilar skull fracture (BSF) are ambiguous, they are widely used to make decisions on initial interventions involving trauma patients. We aimed to assess the performance of early and late (within 48 hr posttrauma) signs for BSF diagnosis and to verify the correlation between the presence of these signs and head injury severity. We conducted a prospectively designed follow-up study at a referral hospital for trauma care in Sao Paulo, Brazil, and performed structured observations for 48 hr post-blunt head injury in patients aged 12 years or older. The following signs of BSF were considered: raccoon eyes, Battle's sign, otorrhea, and rhinorrhea. Among the 136 enrolled patients (85.3% male; mean age 40 ± 21.4 years), 28 patients (20.6%) had BSF. The clinical signs for the early or late detection of BSF had low accuracy (55.9% vs. 43.4%), specificity (52.8% vs. 30.5%), and positive predictive value (25.7% vs. 27.1%). However, the presence of these signs was correlated to head injury severity, indicated by the Glasgow Coma Scale (p = .041) and Maximum Abbreviated Injury Scale-Head region (p = .002). In view of the low accuracy of these signs, resulting low clinical value of their presence, and their high sensitivity in the late stage, the study results contraindicate the value of BSF signs for making decisions about using the nasal route for the introduction of catheters and tubes in initial trauma care.

Sinais clínicos de fratura da base do crânio e seu desempenho no dignóstico dessa lesão / Clinical signs associated with skull base fracture and is performance on the diagnosis of this injury

Introdução: A fragilidade dos sinais clínicos de fratura de base do crânio (FBC) para o diagnóstico dessa lesão, contraposta pela relevância atribuída a esses sinais, motivou a atual investigação, tendo em vista, sobretudo, a importância do diagnóstico dessa fratura nas intervenções iniciais ao doente traumatizado. Objetivos: Descrever o desempenho dos sinais clínicos de FBC para o diagnóstico dessa lesão; verificar o desempenho do hematoma periorbital e/ou rinorreia para diferenciar a fratura de fossa anterior das demais fraturas da base do crânio; descrever o tempo pós-trauma de aparecimento dos sinais clínicos em vítimas com e sem FBC; descrever o desempenho dos sinais de FBC na identificação precoce desse tipo de lesão; verificar a associação entre a presença de sinais clínicos de FBC e as variáveis idade do paciente e gravidade do trauma craniencefálico (TCE). Método: Estudo prospectivo do tipo follow up realizado por meio de observação estruturada de vítimas de TCE até 48 horas após trauma. Foram estudados indivíduos com idade ≥ 12 anos, com TCE contuso, atendidos na Unidade de Emergência Cirúrgica da Casa de Saúde Santa Marcelina entre agosto de 2012 e janeiro de 2013. Essa investigação foi focada nos sinais de FBC clássicos, apreciados rotineiramente na prática assistencial: hematoma periorbital, hematoma retrouricular, otorreia e rinorreia. Nas análises, o padrão-ouro para diagnóstico de FBC foi a tomografia computadorizada ou a visualização direta dessa fratura em cirurgia. Para avaliar o desempenho dos sinais clínicos de FBC, foi calculado seu valor preditivo positivo (VPP) e negativo (VPN), a sensibilidade, a especificidade e a acurácia. O teste quiquadrado foi aplicado para verificar as associações entre as variáveis.Resultados: A casuística foi composta de 136 vítimas com TCE, das quais 28 tiveram FBC. Os sinais clínicos de FBC observados nas primeiras 48 horas pós-trauma apresentam VPP = 25,7%, VPN = 94,3%, sensibilidade de 92,8%, especificidade de 30,5% e ecurácia de 43,4%. Quando detectados na primeira hora, os sinais clínicos tiveram o seguinte desempenho: VPP = 27,1%, VPN = 86,4, sensibilidade de 67,8%, especificidade de 52,8% e acurácia de 55,9%. Vítimas com ou sem FBC tiveram evidências clínicas desse tipo de fratura após a primeira hora do trauma, 21,0% entre 1 e 6 horas e 9,0% após 6 horas. Entre os indivíduos com FBC e sinais clínicos, 26,9% tiveram manifestação mais tardia desse tipo de lesão. A presença de sinais clínicos de FBC em vítimas de TCE se associou com a sua gravidade (p=0,041 e 0,002), porém não esteve relacionada com a idade (p = 0,350). Nas vítimas com FBC, as evidência clínicas específicas de lesão de fossa anterior tiveram acurácia de 53,6%, VPP = 42,8%, VPN = 85,5%, sensibilidade de 90,0% e especificidade de 33,3%. Conclusão: Os resultados do atual estudo contraindiciam a valorização dos sinais de FBC na decisão do uso da via nasal para introdução de cateter e cânulas no atendimento inicial da vítima de trauma, visto que é baixa a acurácia desses sinais, sua presença tem pouco valor clínico e a ausência apresenta bom valor preditivo tardiamente.

Introduction: The fragility of the clinical signs for skull base fracture (SBF) diagnosis and, on the other hand, the importance attributed to these signals motivated this research, especially because of the importance of the fracture diagnosis in the first interventions on the trauma patient. Objectives: To describe the performance of clinical signs on the SBF diagnosis; to verify the performance of periorbital hematoma and/or rhinorrhea to differentiate a anterior fossa fracture from other skull base fractures; to describe the trauma clinical signs onset in victims with or without SBF; to describe the signs performance in the early identification of SBF; to verify the association between SBF clinical signs and age of the patient and severity of head injury (SHI) variables. Methods: Prospective follow-up conducted through structured observation of skull brain trauma (SBT) victims within 48 hours after trauma. The study was about subjects aged 12 years with blunt SBT, treated at the Emergency Surgical Unit at the Santa Marcelina Hospital between August 2012 and January 2013. This investigation was focused on classical SBF signs routinely examinated in healthcare practice: periorbital hematoma, retroauricular hematoma, otorrhea and rhinorrhea. In the analysis, the gold standard for SBF diagnosis was computed tomography or direct visualization of the fracture on surgery. To evaluate the performance of SBF clinical signs, it was calculated its positive predictive value (PPV) and negative predictive value (NPV), sensitivity, specificity and accuracy. The chi-square test was used to assess relationships between variables.Results: The sample consisted of 136 SBT victims, 28 of whom had SBF. Clinical signs of SBF observed in the first 48 hours post-trauma showed PPV 25.7%, NPV 94.3%, sensitivity 92.8%, specificity 30.5% and accuracy 43.4%. When detected in the first hour, the clinical signs performed as follows: PPV 27.1%, NPV 86.4%, sensitivity 67.8%, specificity 52.8% and accuracy 55.9%. Victims with or without SBF showed clinical evidence of this kind of fracture after the first hour of injury, 21,0% between 1 and 6 hours and 9,0% after 6 hours. Among individuals with SBF and clinical signs, 26.9% had a later manifestation of this lesion. The presence of SBF clinical signs in SBT was associated with severity (p = 0.041 and 0.002), but was not related with age (p = 0.350). In victims with SBF, specific clinical evidence of anterior fossa injury had an accuracy of 53.6%, PPV 42.8%, NPV 85.5%, sensitivity 90,0% and specificity 33.3%. Conclusion: The results of this study contraindicated the recovery of SBF signs in the decision of the nasal cannula use and catheter placement in the initial care of the trauma victim, since the accuracy of these signals is low, their presence has little clinical value and the absence has good predictive value later.