Lung function and stress echocardiography in pulmonary arterial hypertension: a cross-sectional study

ABSTRACT BACKGROUND: The mechanism of exercise limitation in idiopathic pulmonary arterial hypertension (IPAH) is not fully understood. The role of hemodynamic alterations is well recognized, but mechanical, ventilatory and gasometric factors may also contribute to reduction of exercise capacity in these individuals. OBJECTIVE: To investigate whether there is an association between ventilatory pattern and stress Doppler echocardiography (SDE) variables in IPAH patients. DESIGN AND SETTING: Single-center prospective study conducted in a Brazilian university hospital. METHODS: We included 14 stable IPAH patients and 14 age and sex-matched controls. Volumetric capnography (VCap), spirometry, six-minute walk test and SDE were performed on both the patients and the control subjects. Arterial blood gases were collected only from the patients. The IPAH patients and control subjects were compared with regard to the abovementioned variables. RESULTS: The mean age of the patients was 38.4 years, and 78.6% were women. The patients showed hypocapnia, and in spirometry 42.9% presented forced vital capacity (FVC) below the lower limit of normality. In VCap, IPAH patients had higher respiratory rates (RR) and lower elimination of CO2 in each breath. There was a significant correlation between reduced FVC and the magnitude of increases in tricuspid regurgitation velocity (TRV). In IPAH patients, VCap showed similar tidal volumes and a higher RR, which at least partially explained the hypocapnia. CONCLUSIONS: The patients with IPAH showed hypocapnia, probably related to their higher respiratory rate with preserved tidal volumes; FVC was reduced and this reduction was positively correlated with cardiac output.

Hydatid cyst in the cervical spinal cord complicated by potentially life-threatening difficult airway: a case report / Cisto hidático na medula cervical complicada por via aérea difícil com potencial risco de vida: relato de caso

Abstract Hydatid cyst in the cervical region is an extremely rare condition that can create challenges for anesthesiologists. Timely recognition of difficult airway and preparing the management plan is crucial to avoid life-threatening complications such as hypoxic brain damage. We describe a case of difficult airway management in a patient with massive cervical hydatid cyst. We used a low-dose ketamine-propofol sedation and lidocaine spray for local oropharyngeal anesthesia. Muscular relaxants were not used, and spontaneous breathing was maintained during intubation. Recognition, assessment, and perioperative planning are essential for difficult airway management in patients with cervical hydatid cyst.

Resumo O cisto hidático na região cervical é uma condição extremamente rara que pode criar desafios para os anestesiologistas. O reconhecimento oportuno das vias aéreas difíceis e a preparação do plano de manejo são cruciais para evitar complicações com risco de vida, como danos cerebrais hipóxicos. Descrevemos um caso de difícil controle das vias aéreas em um paciente com cisto hidático cervical maciço. Utilizamos sedação com cetamina-propofol em baixa dose e spray de lidocaína para anestesia local orofaríngea. Relaxantes musculares não foram utilizados e a respiração espontânea foi mantida durante a intubação. O reconhecimento, a avaliação e o planejamento perioperatório são essenciais para o manejo difícil das vias aéreas em pacientes com cisto hidático cervical.