Research progress of spontaneous respiration in mechanical ventilation of acute respiratory distress syndrome / 中华危重病急救医学

Mechanical ventilation is an important supportive treatment for acute respiratory distress syndrome (ARDS). However, improper mechanical ventilation can cause a "second hit" to the lung, that is, ventilator-induced lung injury (VILI), characterized by translocation of pulmonary inflammatory mediators into the bloodstream, aggravating systemic inflammatory response syndrome, and multiple organ failure. Although the current protective mechanical ventilation strategy plays an important role in supporting treatment, the mortality of ARDS with mechanical ventilation is still very high. Therefore, to explore the strategy of pulmonary protective ventilation has always been the key orientation of ARDS and has important clinical significance. This article reviews the application, advantages and disadvantages of assisted and non-assisted spontaneous respiration in ARDS patients undergoing mechanical ventilation, in order to provide a reference for research and development of new strategies for ARDS protective ventilation.

Early identification of potential brain death organ donors based on prediction of spontaneous respiratory arrest

Background: This study was designed to build a Nomogarm prediction model of spontaneous respiratory arrest (SRA) in nerocritical patients within 72 hours after brain injury for early identification of potential brain death organ donors.Methods: From October 2017 to May 2019, the neurocritical patients admitted to the First Affiliated Hospital of Sun Yat-sen University, were enrolled. The occurrence of SRA within 72 hours after brain injury was regarded as the time interest point and grouping factor, factors associated with SRA were screened by univariate and multivariate analysis, and then the Nomogarm prediction model was developed. Finally, the Nomogarm prediction model was tested in the validation set.Results: In training set, univariate and multivariate analysis showed that the midline shift (OR=4.56, 95% 1.87-19.21), absent of ambient cistern (OR=4.83, 95% 1.35-16.34), cough reflex absence (OR=3.82, 95% 1.15-12.42), intraventricular hemorrhage (OR=3.16, 95% 1.53-14.52) and serum Na+<125mmol/L (OR=3.06, 95% 1.53-13.44) were associated with SRA within 72 hours. In the training set and validation set, the predicted C index of SRA rate within 72 hours was 0.81 (95% CI 0.76-0.85) and 0.80 (95% CI 0.75-0.83), respectively. Further statistical analysis showed that 140 points, 160 points and 170 points were dangerous cut-off points, of which 140 points, 160 points and 170 points were 30.1%, 65.6% and 93.4% associated with SRA within 72 hours, respectively.Conclusions: Nomogram prediction model based on brain injury assessment parameters can predict the time of SRA in neurocritical patients, and can be used for early identification of potential brain death organ donors.

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.

Clinical applicafion of non-intubated uniportal video-assisted thoracoscopic surgery with spontaneous respiration / 重庆医学

Objective To explore the feasibility and safety of uniportal video-assisted thoracoscopic surgery under non-intubated anesthesia with spontaneous respiration.Methods The clinical data in 35 cases of uniportal video-assisted thoracoscopic surgery under non-intubated anesthesia with spontaneous respiration implemented by same doctor and team in the Affiliated Nanjing Chest Hospital of Medical College,Southeast University from June 2016 to January 2017 were retrospectively analyzed.Results The operations were successfully completed in 35 cases,including 23 cases of lung bullae resection,6 cases of lung wedge resection,5 cases of pulmonary lobectomy and lymph nodes clearance,and 1 case of bilateral sympathectomy.The operative time was 20-106min,average(38.79 ± 26.45) min,intraoperative bleeding volume was 20-350 mL,average(57.14 ± 56.50) mL.No perioperative serious complications or death occurred.Conclusion Uniportal video-assisted thoracoscopic surgery technique under non-intubated anesthesia with spontaneous respiration is safe and feasible,and can be selectively used in partial patients.

Comparison of Fentanyl and Remifentanil in children underwent airway foreign body removal / 中国内镜杂志

Objective To compare the safety and effectiveness of Propofol-Fentanyl and Propofol-Remifentanil total intravenous anesthesia for airway foreign body (FB) removal in children. Method 280 children aged 1 ~ 3 years underwent rigid bronchoscopy for FB removal were randomized into two groups. The Fentanyl group (Group F, n = 140) were given Propofol 2.00~3.00 mg/kg and Fentanyl 2.00 μg/kg for induction and Propofol 200.00 ~ 500.00 μg/(kg·min) for maintenance of anesthesia. The Remifentanil group (Group R, n = 140) were given Propofol 2.00 ~ 3.00 mg/kg and Remifentanil 1.00 ~ 1.50 μg/kg for induction of anesthesia, while anesthesia was maintained with Propofol 200.00 ~ 500.00 μg/(kg·min) and Remifentanil 0.10 ~ 0.20 μg/(kg·min). All the children during the procedure were with spontaneous respiration. SpO2 before inserting rigid bronchoscope (T1), 1 min (T2) and 3 min (T3) after insertion, 3 min (T4) and 10 min (T5) after extraction were recorded. PETCO2 after endoscopy (T6) was measured. Adverse events, including body movement, cough, breath-holding, and hypoxemia,were observed. The time of induction, surgery, recovery and the total dosage of the intravenous agents were recorded. Results SpO2 of the two groups were in normal range at T1 ~ 5, which was higher in group R than group F at T2 ~ 5 (P < 0.05). PETCO2 of group R was lower than group F at T6 (P < 0.05). The rate of body movement and cough were comparable between the two groups (P > 0.05), while breath-holding and hypoxemia were more frequent in group F (P < 0.05). The time of induction and recovery were shorter in group R (P < 0.05), while surgery time and the Propofol dosage were similar (P > 0.05). The total dose of Fentanyl was significantly higher than Remifentanil (P < 0.05). Conclusion Combination of Propofol with Fentanyl or Remifentanil both produce effective anesthesia in children undergoing FB removal. But Propofol-Remifentanil provides more stable oxygen saturation, faster induction and recurrence of anesthesia, as well as less intraoperative complications.

Pneumothorax after restoration of spontaneous respiration in a patient with liver segmentectomy: A case report / 대한마취과학회지

Pneumothroax may occur during and after general anesthesia unexpectedly, and the diagnosis may be difficult when the manifestations are non-specific. An early diagnosis and treatment is important to prevent tension pneumothorax. Pneumothorax can be occurred from injury to the chest wall, airway, lung, and diaphragm. We report a case of a 50-year-old female patient who underwent segmentectomy of liver under general anesthesia and developed pneumothorax after restoration of spontaneous respiration from unexpected diaphragm injury.

During Inhalation Anesthesia with Sevoflurane Using LMA, Spontaneous Breathing is Feasible / 대한마취과학회지

BACKGROUND: Sevoflurane is used as an anesthetic agent is now commonly. Several studies have reported on the use of sevoflurane in spontaneous breathing patients. However none of these studies focused on spontaneous breathing under sevoflurane anesthesia with a laryngeal mask airway (LMA). The purpose of the present study was to assess the feasibility of spontaneous breathing during inhalation anesthesia using sevoflurane with an LMA. METHODS: We studied 50 patients undergoing elective upper/lower extremity surgery in which muscle relaxation was not required. All patients received thiopental sodium 5.5 mg/kg after glycopyrrolate 0.004 mg/kg premedication. They were allowed to breathe spontaneously after the insertion of an LMA under sevoflurane anesthesia. Ventilation was measured before induction and ventilatory variables of 3-4% sevoflurane were measured during spontaneous ventilation. Arterial blood gas analysis was also performed in both phases. RESULTS: During spontaneous breathing under sevoflurane anesthesia with LMA, tidal volume (TV) significantly reduced and respiration rate (RR) increased versus resting ventilation (P < 0.05). But, minute volume (MV) was not significantly different. PaCO2, HCO3-, total CO2, BE were all significantly increased (P < 0.05). CONCLUSIONS: It was concluded that spontaneous breathing can be maintained during clinical depth sevoflurane inhalation anesthesia in patients without a cardiopulmonary abnormality.

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.

Cardiovascular Effects of Anesthetic induction with Midazolam for Open Heart Surgery / 대한마취과학회지

Midazolam, an imidazobenzodiazepine derivative, is utilized as a premedicant, sedative and anesthetic induction agent. Cnmpared to diazepam, midazolam is characterized by better solubility in water, better venous tolerance and a more rapid onset of action. Though the onset of pharmacological action of midazolam takes longer than thiopental, midazolam exerts more gradual effects on circula- tion than thiopental. Because it maintains hemodynamic stability and induces amesthesia smoothly, madazolam is a potential alternative as an induction agent in high-risk patients. To evaluate the safe margin of i. v. midazolam and to investigate the effect of carbon dioxide retention by midazolam, 32 cardiac patients were divided into 4 groups: Group I, midazolam 0.2 mg/ kg with spontaneous respiration: Group II, midazolam 0.2 mg/kg with assist respiration: Group III, midazolam 0.4 mg/kg with assist respiration: Group IV, midazolam 0.4 mg/kg with spontaneons respiration. In each group, systolic blood pressure, diastolic blood pressure, heart rate, respiratory rate, cardiac output and arterial blood gas analysis were checked before and 2,4 and 6 minutes after i. v. injection of midazolam. Systolic blood pressure decreased significantly after injection of midazolam in all four groups. Diastolic blood pressure decreased significantly in group II and IlI. Systolic blood pressure was lower in group III than II 4 and 6 minutes following midazolam administration. The elevation of arterial carbon dioxide tension in group I and IV did not cause any changes in cardiovascular variables. The time from the end of injection of midazolam to spontanous closing of eyes and the time from the end of injection to disappearance of eyelash reflex were measured. But there were no significant differen-ces between all four groups. .On the basis of these data, we could conclude that in unpremedicated patients for open heart surgery midazolam alone allows rapid and smooth induction. In case of using the dose of 0.4 mg/kg, care must be taken in the decrease of systolic blood pressure.