Abstract Background Thyromental height (TMH) was first reported as a great single test for prediction of difficult laryngoscopies, although further studies have shown variable estimates of its accuracy. We thus performed this meta-analysis to summarize the predictive values of TMH mainly for prediction of difficult laryngoscopies. Methods A search in PubMed, EMBASE, LILACS, and Scielo was conducted in June 2020. We included prospective cohorts fully reported with patients ≥ 16 years old, providing data on predictive values of TMH for prediction of either difficult laryngoscopies or difficult intubations. Diagnostic properties and association between TMH and Cormack and Lehanes’s classification by direct laryngoscopy were evaluated. A random-effects meta-analysis using hierarchical models was performed. Results Eight studies evaluating 2844 patients were included. All included studies had high risk of bias and low concern regarding applicability. There was significant heterogeneity among the studies. The pooled diagnostic odds ratio (DOR) and positive (LR+) and negative (LR-) likelihood ratios were as follows: DOR, 57.94 (95% CI: 18.19-184.55); LR+, 11.32 (95% CI: 4.28-29.92); and LR-, 0.23 (95% CI: 0.15-0.35). Summary sensitivity and specificity for studies with common threshold were 82.6 (95% CI: 74-88.8%) and 93.5 (95% CI: 79-98.2%), respectively. The estimated AUC was 81.1%. Conclusion TMH arises as a good predictor of difficult laryngoscopies in adult patients from diverse populations presenting better predictive values than most previously reported bedside tests. However, the high risk of bias throughout the studies may have skewed the results of the individual research as well as the summary points of the present meta-analysis.

Objetivo Identificar a realização de procedimentos altamente recomendados para assegurar a via aérea de pacientes submetidos a anestesia, previstos no manual de segurança anestésica da Organização Mundial da Saúde. Métodos Realizou-se um estudo prospectivo do tipo transversal observacional, envolvendo 87 pacientes com idade entre 18 e 60 anos, ASA 1 e 2 de acordo com a classificação do Estado Físico pela Sociedade Americana de Anestesiologia. Variáveis estudadas: realização do teste de Mallampati, disponibilidade de material para intubação orotraqueal, confirmação do posicionamento do tubo endotraqueal, monitoração da ventilação do paciente e confirmação do jejum. Calculou-se a Razão de Prevalência (RP) e o seu Intervalo de Confiança a 95% (IC 95%) como medida do risco relativo. Adotou-se o nível de significância de 5%. Resultados Em 87,4% dos pacientes a via aérea não foi avaliada pelo teste de Mallampati e 51,7% não tiveram seus jejuns pré-operatórios confirmados, e em 29,1% das anestesias não se verificou a disponibilidade de material para intubação orotraqueal. Todos os casos em que não ocorreu esta verificação o paciente foi submetido à anestesia regional, com diferença significativa entre os grupos (p = 0.00). 95,8% dos pacientes tiveram a intubação orotraqueal confirmada pela capnografia e 68% tiveram esta confirmação realizada pela ausculta. Conclusão Medidas consideradas essenciais para a segurança do paciente durante a cirurgia ainda são negligenciadas.

Objective To identify compliance with the procedures for securing the airway of patients submitted to anesthesia, defined as highly recommended in the World Health Organization Surgical Safety Checklist. Methods A prospective, cross-sectional, observational study was conducted with 87 patients aged 18 to 60 years, classified as ASA grade 1 or 2 according to the American Society of Anesthesiologists’ Physical Status Classification. The study variables consisted of: whether the Mallampati test had been performed, whether equipment was readily available for orotracheal intubation, whether the correct placement of the endotracheal tube was verified, whether patient ventilation was monitored and whether fasting was confirmed. Prevalence ratios and their respective 95% confidence intervals were calculated as measures of relative risk. Statistical significance was defined at 5%. Results It was found that in 87.4% of patients, the airway was not evaluated using the Mallampati classification and in 51.7% of cases, preoperative fasting was not confirmed. In 29.9% of cases, the ready availability of equipment for orotracheal intubation was not verified. In all of the cases in which the availability of this equipment was not checked, the patient was submitted to regional anesthesia, with a statistically significant difference compared to the cases in which the patient was submitted to general anesthesia. Conclusion Measures considered essential for the safety of the patient during surgery are still being ignored.

OBJETIVOS: determinar os desfechos maternos e neonatais de acordo com a aplicação ou não de estimulação elétrica transcutânea (EET) para alívio da dor do trabalho de parto antes da instalação da técnica combinada (raquianestesia + peridural). MÉTODOS: realizou-se ensaio clínico, randomizado, aberto, envolvendo 22 parturientes, com gestação a termo e feto único em apresentação cefálica, atendidas em hospital-escola de nível terciário em Recife, Brasil. Estas pacientes foram randomizadas para receber ou não EET antes da instalação da anestesia combinada (raquianestesia + anestesia peridural) para analgesia de parto. Avaliaram-se a intensidade da dor pela escala analógica visual (EAV), o tempo transcorrido entre a avaliação inicial e a necessidade de instalação da anestesia combinada, a duração do trabalho de parto, a freqüência de cesariana e parto instrumental, os escores de Apgar e a freqüência de hipóxia neonatal. Para análise estatística, foram utilizados os testes de Mann-Whitney e exato de Fisher, considerando-se o nível de significância de 5%. RESULTADOS: o tempo decorrido entre a avaliação da dor da parturiente e a necessidade de instalação da técnica combinada foi significativamente maior no grupo da EET (mediana de 90 minutos) quando comparado ao grupo controle (mediana de 30 minutos). A duração do trabalho de parto foi similar nos dois grupos (em torno de seis horas). Não houve diferença na evolução dos escores de EAV durante o trabalho de parto. A freqüência de cesariana foi de 18,2% nos dois grupos. Apenas um parto foi ultimado a fórcipe, no grupo controle. A mediana do escore de Apgar no quinto minuto foi 10, não se encontrando nenhum caso de hipóxia neonatal. CONCLUSÕES: a aplicação de EET foi efetiva em retardar a instalação da anestesia combinada para manter analgesia satisfatória durante o trabalho de parto, porém não apresentou efeito significativo sobre a intensidade da dor e a duração do trabalho de parto. Não houve efeitos deletérios maternos e neonatais.

PURPOSE: to determine maternal and neonatal outcome according to the application or not of transcutaneous electrical nerve stimulation (TENS) for relief of labor pain before installation of combined spinal epidural (CSE) block. METHODS: a randomized open clinical trial was conducted involving 22 parturients with a singleton, vertex, term fetus, managed in a tertiary-care academic medical center in Recife, Brazil. These patients were randomly assigned to receive or not TENS before CSE block for labor analgesia. Outcome analysis included pain intensity as measured by visual analog scale (VAS), interval between initial evaluation and CSE installation, labor duration, cesarian section and instrumental delivery rate, Apgar scores and frequency of neonatal hypoxia. Statistical analysis was performed using Mann-Whitney and Fisher's exact tests with a 5% level of significance. RESULTS: a significantly prolonged interval between initial evaluation and CSE block was observed in the TENS group (median of 90 min) when compared with the control group (median of 30 min). Duration of labor was similar (about 6 h). No significant difference was found in VAS scores. Cesarian section rate was 18.2% in both groups. There was only one forceps delivery (in the control group). The median of Apgar scores at the 5th minute was 10 and no case of neonatal hypoxia was found. CONCLUSONS: TENS was effective in delaying CSE analgesia installation without affecting pain intensity and duration of labor. There were no adverse effects on mothers or newborns.