Feasibility of non-intubated anesthesia and regional block for thoracoscopic surgery under spontaneous respiration: a prospective cohort study

Data about the feasibility and safety of thoracoscopic surgery under non-intubated anesthesia and regional block are limited. In this prospective study, 57 consecutive patients scheduled for thoracoscopic surgery were enrolled. Patients were sedated with dexmedetomidine and anesthetized with propofol and remifentanil. Ropivacaine was used for intercostal nerve and paravertebral block. Lidocaine was used for vagal block. The primary outcomes were mean arterial pressure (MAP), heart rate (HR), oxygen saturation, and end-tidal carbon dioxide partial pressure (ETCO2) at T0 (pre-anesthesia), T1 (immediately after laryngeal mask/nasopharyngeal airway placement), T2 (immediately after skin incision), T3 (10 min after opening the chest), T4 (end of surgery), and T5 (immediately after laryngeal mask/nasopharyngeal airway removal). One patient required conversion to intubation, 15 developed intraoperative hypotension, and two had hypoxemia. MAP at T0 and T5 was higher than at T1-T4; MAP at T3 was lower (P<0.05 vs other time points). HR at T0 and T5 was higher (P<0.05 vs other time points). ETCO2 at T2 and T3 was higher (P<0.05 vs other time points). Arterial pH, PCO2, and lactic acid at T1 differed from values at T0 and T2 (P<0.05). The Quality of Recovery-15 (QoR-15) score at 24 h was lower (P<0.05). One patient experienced dysphoria during recovery. Thoracoscopic surgery with regional block under direct thoracoscopic vision is a feasible and safe alternative to conventional surgery under general anesthesia, intubation, and one-lung ventilation.

Síndrome de Raynaud secundario: disminución del flujo sanguíneo de la piel entre los episodios isquémicos y prolongación de la vasoconstricción con las maniobras respiratorias / Secondary Raynaud's syndrome: skin blood flow decrease between the ischemic episodes and prolongation of the vasoconstriction during the respiratory maneuvers

El síndrome de Raynaud se caracteriza por isquemia cutánea digital episódica, manifestada por palidez, cianosis y rubor de los dedos de manos y pies expuestos al frío o cuando el paciente está sujeto a un estrés emocional. No se conoce el mecanismo fisiopatológico exacto; la hipótesis más invocada es una alteración autonómica en la inervación simpática de los vasos sanguíneos de la piel. Objetivo: Estudiar los cambios de la frecuencia cardíaca y el flujo sanguíneo de la piel (FSP) en sujetos sanos y en pacientes con síndrome de Raynaud durante las siguientes condiciones: 1. respiración espontánea (RE), 2. respiración rítmica (RR), 3. inspiración profunda repentina (IPR), 4. maniobra de Valsalva (MV). Método: Se estudiaron 22 sujetos sanos y 22 pacientes con síndrome de Raynaud secundario. Las variables medidas fueron: 1. intervalo R-R; 2. amplitud de FSP; 3. porcentaje de disminución de FSP; 4. latencia de la máxima disminución del FSP. Resultados: Los pacientes con síndrome de Raynaud presentaron mayor taquicardia basal. La amplitud del FSP se encontró disminuido durante la respiración espontánea y durante las maniobras respiratorias (P < 0.001). La vasoconstricción estuvo prolongada ya que la latencia promedio de recuperación del FSP estuvo prolongada en IPR y MV en comparación de los sujetos controles. Conclusión: La amplitud del FSP basal está disminuida en los pacientes con síndrome de Raynaud, durante períodos asintomáticos; esto sugiere daño endotelial. También se encontró disminuido con las diversas maniobras respiratorias (RR, IPR y MV). Este cambio dinámico sugiere hiperactividad simpática hacia los vasos sanguíneos de la piel.

The Raynaud's syndrome is an episodic skin ischemia manifested by pallor, cyanosis and erythema of the fingers in response to cold or emotional stress. The exact pathophysiology is unknown but it has been hypothetised that may be due to an autonomic alteration in the sympathetic innervation of skin blood vessels. Objective: To study the changes of heart rate and skin bloodflow (SBF) in healthy subjects and in patients with secondary Raynaud's syndrome during different respiratory maneuvers: 1. spontaneous respiration; 2. rhythmic respirations (RR), 3. sudden inspirations (SI), and 4. Valsalva maneuver (VM). Methods: We studied 22 healthy subjects and 22 patients with secondary Raynaud's syndrome. The variables measured were: 1) RR intervals; 2) amplitudes of SBF; 3) percentage of decrease of SBF; 4) latency of the maximum decrease of SBF. Results: In all patients with secondary Raynaud's syndrome the SBF was decreased basally during spontaneous respirations and during all respiratory maneuvers (p < 0.001). The mean latency of recovery of the SBF was prolonged during sudden deep inspiration. The patients with Raynaud also had significant basal tachycardia at rest (p < 0.003). Conclusions: The basal skin blood flow during spontaneous respirations and in asymptomatic periods is decreased in patients with Raynaud's syndrome; this may be related to endothelial arterioral damage. The SBF was also significantly decreased dynamically during sudde3n inspirations (SI), rhythmic breathing (RR) and Valsalva maneuver (VM). This dynamic change suggests sympathetic hyperactivity.