Association between computed tomography-quantified respiratory muscles and chronic obstructive pulmonary disease: a retrospective study.

BACKGROUND: This study examined the association between chest muscles and chronic obstructive pulmonary disease (COPD) and the relationship between chest muscle areas and acute exacerbations of COPD (AECOPD). METHODS: There were 168 subjects in the non-COPD group and 101 patients in the COPD group. The respiratory and accessory respiratory muscle areas were obtained using 3D Slicer software to analysis the imaging of  computed tomography (CT). Univariate and multivariate Poisson regressions were used to analyze the number of AECOPD cases during the preceding year. The cutoff value was obtained using a receiver operating characteristic (ROC) curve. RESULTS: We scanned 6342 subjects records, 269 of which were included in this study. We then measured the following muscle areas (non-COPD group vs. COPD group): pectoralis major (19.06 ± 5.36 cm2 vs. 13.25 ± 3.71 cm2, P < 0.001), pectoralis minor (6.81 ± 2.03 cm2 vs. 5.95 ± 1.81 cm2, P = 0.001), diaphragmatic dome (1.39 ± 0.97 cm2 vs. 0.85 ± 0.72 cm2, P = 0.011), musculus serratus anterior (28.03 ± 14.95 cm2 vs.16.76 ± 12.69 cm2, P < 0.001), intercostal muscle (12.36 ± 6.64 cm2 vs. 7.15 ± 5.6 cm2, P < 0.001), pectoralis subcutaneous fat (25.91 ± 13.23 cm2 vs. 18.79 ± 10.81 cm2, P < 0.001), paravertebral muscle (14.8 ± 4.35 cm2 vs. 13.33 ± 4.27 cm2, P = 0.007), and paravertebral subcutaneous fat (12.57 ± 5.09 cm2 vs. 10.14 ± 6.94 cm2, P = 0.001). The areas under the ROC curve for the pectoralis major, intercostal, and the musculus serratus anterior muscle areas were 81.56%, 73.28%, and 71.56%, respectively. Pectoralis major area was negatively associated with the number of AECOPD during the preceding year after adjustment (relative risk, 0.936; 95% confidence interval, 0.879-0.996; P = 0.037). CONCLUSION: The pectoralis major muscle area was negative associated with COPD. Moreover, there was a negative correlation between the number of AECOPD during the preceding year and the pectoralis major area.

Ability of parasternal intercostal muscle thickening fraction to predict reintubation in surgical patients with sepsis.

OBJECTIVES: We aimed to evaluate the ability of the parasternal intercostal (PIC) thickening fraction during spontaneous breathing trial (SBT) to predict the need for reintubation within 48 h after extubation in surgical patients with sepsis. METHODS: This prospective observational study included adult patients with sepsis who were mechanically ventilated and indicated for SBT. Ultrasound measurements of the PIC thickening fraction and diaphragmatic excursion (DE) were recorded 15 min after the start of the SBT. After extubation, the patients were followed up for 48 h for the need for reintubation. The study outcomes were the ability of the PIC thickening fraction (primary outcome) and DE to predict reintubation within 48 h of extubation using area under receiver characteristic curve (AUC) analysis. The accuracy of the model including the findings of right PIC thickening fraction and right DE was also assessed using the current study cut-off values. Multivariate analysis was performed to identify independent risk factors for reintubation. RESULTS: We analyzed data from 49 patients who underwent successful SBT, and 10/49 (20%) required reintubation. The AUCs (95% confidence interval [CI]) for the ability of right and left side PIC thickening fraction to predict reintubation were 0.97 (0.88-1.00) and 0.96 (0.86-1.00), respectively; at a cutoff value of 6.5-8.3%, the PIC thickening fraction had a negative predictive value of 100%. The AUCs for the PIC thickening fraction and DE were comparable; and both measures were independent risk factors for reintubation. The AUC (95% CI) of the model including the right PIC thickening fraction > 6.5% and right DE ≤ 18 mm to predict reintubation was 0.99 (0.92-1.00), with a positive predictive value of 100% when both sonographic findings are positive and negative predictive value of 100% when both sonographic findings are negative. CONCLUSIONS: Among surgical patients with sepsis, PIC thickening fraction evaluated during the SBT is an independent risk factor for reintubation. The PIC thickening fraction has an excellent predictive value for reintubation. A PIC thickening fraction of ≤ 6.5-8.3% can exclude reintubation, with a negative predictive value of 100%. Furthermore, a combination of high PIC and low DE can also indicate a high risk of reintubation. However, larger studies that include different populations are required to replicate our findings and validate the cutoff values.

Graded onset of parasternal intercostal inspiratory activity detected with surface electromyography in healthy young females and males.

Intramuscular recordings of single motor unit activity from parasternal intercostal muscles show a rostrocaudal gradient in timing and amplitude of inspiratory activity. This study determined the feasibility of surface electromyographic activity (EMG) to measure graded parasternal intercostal activity in young females and males during quiet breathing and breathing with inspiratory resistive loads. Surface EMGs were recorded from the 1st-to-5th parasternal intercostal muscles during 10 min of breathing. EMGs were processed to remove 50 Hz and electrocardiogram artifacts and integrated. Amplitude and onset time of inspiratory activity were measured from waveform averages triggered at the onset of inspiratory flow. Onset times were measured independently by two assessors, blinded to interspace and EMG scale, with excellent agreement (ICC3,k = 0.86). The onset of inspiratory activity in the 1st-to-3rd interspaces was at or within ∼400 ms of the start of inspiratory airflow, but activity in the caudal (4th and 5th) spaces was delayed by up to ∼1,000 ms (P < 0.001). There was no main effect of sex on onset time (P = 0.07), but an interaction with interspace (P < 0.001) revealed that inspiratory activity in the caudal interspaces was delayed by 15% of inspiratory time in female participants compared with 30% of inspiratory time in male participants. Inspiratory loads did not affect EMG onset time (P = 0.31). Thus, surface EMG is feasible to assess the onset time of inspiratory activity as a marker of inspiratory neural drive and pattern of activation across spaces, in both females and males.NEW & NOTEWORTHY We demonstrated that surface EMG is a valid method to measure graded inspiratory EMG in the parasternal intercostal muscles in healthy young male and female participants during quiet breathing and loaded breathing. Across the 1st-to-5th interspaces, there was more homogenous activation in women and more graded activity in men across parasternal intercostal muscles during breathing. By recording surface EMG from both male and female participants, we have revealed sex differences in inspiratory activity across intercostal muscles.

Neural respiratory drive assessment and its correlation with inspiratory muscle strength in patients undergoing open-heart surgery: A cross-sectional study.

BACKGROUND AND PURPOSE: Pulmonary dysfunction and inspiratory muscle weakness are frequently observed after cardiac surgery. Understanding the load on and capacity of respiratory muscles can provide valuable insights into the overall respiratory mechanics and neural regulation of breathing. This study aimed to assess the extent of neural respiratory drive (NRD) and determine whether admission-to-discharge differences in NRD were associated with inspiratory muscle strength changes among patients undergoing open-heart surgery. METHODS: This cross-sectional study was conducted on 45 patients scheduled for coronary artery bypass graft or heart valve surgery. NRD was measured using a surface parasternal intercostal electromyogram during resting breathing (sEMGpara tidal) and maximal inspiratory effort (sEMGpara max). Maximal inspiratory pressure (MIP) was used to determine inspiratory muscle strength. Evaluations were performed on the day of admission and discharge. RESULTS: There was a significant increase in sEMGpara tidal (6.9 ± 3.6 µV, p < 0.001), sEMGpara %max (13.7 ± 11.2%, p = 0.008), and neural respiratory drive index (NRDI, the product of EMGpara %max and respiratory rate) (337.7 ± 286.8%.breaths/min, p < 0.001), while sEMGpara max (-43.6 ± 20.4 µV, p < 0.01) and MIP (-24.4 ± 10.7, p < 0.001) significantly decreased during the discharge period. Differences in sEMGpara tidal (r = -0.369, p = 0.045), sEMGpara %max (r = -0.646, p = 0.001), and NRDI (r = -0.639, p = 0.001) were significantly associated with a reduction in MIP. DISCUSSION: The findings indicate that NRD increases after open-heart surgery, which corresponds to a decrease in inspiratory muscle strength.

The ratio of parasternal intercostal muscle-thickening fraction-to-diaphragm thickening fraction for predicting weaning failure.

BACKGROUND: Diaphragm dysfunction is associated with weaning outcomes in mechanical ventilation patients, in the case of diaphragm dysfunction, the accessory respiratory muscles would be recruited. The main purpose of this study is to explore the performance of parasternal intercostal muscle thickening fraction in relation to diaphragmatic thickening fraction ratio (TFic1/TFdi2) for predicting weaning outcomes, and compare its accuracy with D-RSBI in predicting weaning failure. MATERIALS AND METHODS: We prospectively enrolled consecutive patients from 7/2022-5/2023. We measured TFic, TFdi, and diaphragmatic excursion (DE3) by ultrasound and calculated the TFic/TFdi ratio and diaphragmatic rapid shallow breathing index (D-RSBI4). Receiver-operator characteristic (ROC5) curves evaluated the accuracy of the TFic/TFdi ratio and D-RSBI in predicting weaning failure. RESULTS: 161 were included in the final analysis, 114 patients (70.8%) were successfully weaned from mechanical ventilation. The TFic/TFdi ratio (AUROC = 0.887 (95% CI: 0.821-0.953)) was superior to the D-RSBI (AUROC = 0.875 (95% CI: 0.807-0.944)) for predicting weaning failure. CONCLUSIONS: The TFic/TFdi ratio predicted weaning failure with high accuracy and outperformed the D-RSBI.

Intercostal Muscle Function During Noninvasive Ventilation and Acute Hypercapnic Respiratory Failure.

BACKGROUND: Noninvasive ventilation (NIV) is a widely used and well-established treatment modality for respiratory failure. In patients with increased respiratory work of breathing, accessory muscles are commonly activated along with the diaphragm. Whereas diaphragm ultrasound has been utilized to assess outcomes of mechanical ventilation, the data on intercostal muscle ultrasound remain limited. We aimed to investigate the association between intercostal muscle thickening fraction (TF) and NIV failure in critical care patients with hypercapnic respiratory failure. METHODS: Critical care subjects receiving NIV for hypercapnic respiratory failure were enrolled in the study. The intercostal muscle TF was measured on admission day (day 0) and the following day (day 1). NIV failure was defined as the need for invasive mechanical ventilation or death during NIV therapy. RESULTS: A total of 158 subjects were enrolled, and 30 experienced NIV failure. Age, sex, and body mass index (BMI) were similar in the NIV success and failure groups. Acute Physiology And Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) scores were higher in the NIV failure group. In terms of causes of respiratory failure, the COPD exacerbation rate was higher in the NIV success group. TF was higher in the NIV failure group on both day 0 and day 1. The increased TF on the ICU admission day, with a cutoff value of 12%, was associated with NIV failure after adjusting for age, sex, BMI, APACHE II, and SOFA. Persistence of a higher TF value on both day 0 and day 1 was also associated with NIV failure risk. CONCLUSIONS: There was a positive relation between intercostal muscle TF measured by ultrasound and NIV failure, even after adjusting for APACHE II and SOFA scores.

Axillary local anesthetic spread after the thoracic interfacial ultrasound block - a cadaveric and radiological evaluation / Dispersão axilar de anestésico local após bloqueio interfascial torácico guiado por ultrassom - estudo radiológico e em cadáver

Abstract Background Oral opioid analgesics have been used for management of peri- and postoperative analgesia in patients undergoing axillary dissection. The axillary region is a difficult zone to block and does not have a specific regional anesthesia technique published that offers its adequate blockade. Methods After institutional review board approval, anatomic and radiological studies were conducted to determine the deposition and spread of methylene blue and local anesthetic injected respectively into the axilla via the thoracic inter-fascial plane. Magnetic Resonance Imaging studies were then conducted in 15 of 34 patients scheduled for unilateral breast surgery that entailed any of the following: axillary clearance, sentinel node biopsy, axillary node biopsy, or supernumerary breasts, to ascertain the deposition and time course of spread of solution within the thoracic interfascial plane in vivo. Results Radiological and cadaveric studies showed that the injection of local anesthetic and methylene blue via the thoracic inter-fascial plane, using ultrasound guide technique, results in reliable deposition into the axilla. In patients, the injection of the local anesthetic produced a reliable axillary sensory block. This finding was supported by Magnetic Resonance Imaging studies that showed hyper-intense signals in the axillary region. Conclusions These findings define the anatomic characteristics of the thoracic interfascial plane nerve block in the axillary region, and underline the clinical potential of this novel nerve block.

Resumo Justificativa Os analgésicos orais à base de opioides têm sido usados para o manejo da analgesia nos períodos peri e pós-operatório de pacientes submetidos à linfadenectomia axilar. A região axilar é uma zona difícil de bloquear e não há registro de uma técnica de anestesia regional específica que ofereça o seu bloqueio adequado. Métodos Após a aprovação do Conselho de Ética institucional, estudos anatômicos e radiológicos foram feitos para determinar a deposição e disseminação de azul de metileno e anestésico local, respectivamente injetados na axila via plano interfascial torácico. Exames de ressonância magnética foram então feitos em 15 de 34 pacientes programados para cirurgia de mama unilateral que envolveria qualquer um dos seguintes procedimentos: esvaziamento axilar, biópsia de linfonodo sentinela, biópsia de linfonodo axilar ou mamas supranumerárias, para verificar a deposição e o tempo de propagação da solução dentro do plano interfascial torácico in vivo. Resultados Estudos radiológicos e em cadáveres mostraram que a injeção de anestésico local e azul de metileno via plano interfascial torácico com a técnica guiada por ultrassom resulta em deposição confiável na axila. Nos pacientes, a injeção de anestésico local produziu um bloqueio sensitivo axilar confiável. Esse achado foi corroborado por estudos de ressonância magnética que mostraram sinais hiperintensos na região axilar. Conclusões Esses achados definem as características anatômicas do bloqueio da região axilar e destacam o potencial clínico desses novos bloqueios.

Hernia pulmonar espontánea secundaria a acceso de tos: reparación por técnica asistida por video / Spontaneous lung hernia secondary to coughing fit: repair by video assisted technique

La hernia pulmonar es la protrusión del tejido pulmonar a través de una de las estructuras que lo contienen. Generalmente, son secundarias a traumatismos o a un procedimiento quirúrgico; con menos frecuencia, pueden ser espontáneas posteriores a accesos de tos. El diagnóstico se hace por el cuadro clínico y debe confirmarse con radiografía o tomografía, con las cuales se puede ver la protrusión del tejido pulmonar a través de los espacios intercostales. Pueden tratarse de manera conservadora si son asintomáticas, pero el tratamiento más común es el quirúrgico, con técnica abierta o asistida por video. Se presenta una revisión bibliográfica y el reporte de un caso manejado con técnica asistida por video.

Lung hernia is the protrusion of lung tissue through one of its bounding structures. Usually it develops as the result of thoracic trauma or after a surgical procedure; less frequently it can be spontaneous after a coughing fit. Diagnosis is made on the basis of the clinical findings and should be confirmed by X-ray imaging or computed tomography, which evidence the protrusion of the lung through the intercostal spaces. Treatment of lung hernia may be conservative when the patient is asymptomatic, but surgical intervention is most commonly performed, which can be by the open technique or by the video assisted technique. We present a literature review and report a case that was managed by the video assisted surgical technique.

Intercostal and forearm muscle deoxygenation during respiratory fatigue in patients with heart failure: potential role of a respiratory muscle metaboreflex

The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66±12 years; left ventricle ejection fraction, 34±3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1±1.3 min in heart failure patients and at 9.3±1.4 min in controls (P<0.05), but perceived effort, changes in heart rate, and in systolic blood pressure were similar between groups (P>0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (P<0.05) along with decreased tissue oxygenation both in intercostal (heart failure, -2.6±1.6%; controls, +1.6±0.5%; P<0.05) and in forearm muscles (heart failure, -4.5±0.5%; controls, +0.5±0.8%; P<0.05). These results suggest that respiratory fatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.

Lesão complexa da traqueia: correção com retalho pediculado de músculo intercostal / Complex tracheal lesion: correction with an intercostal muscle pedicle flap

A reconstrução esofágica é uma das mais complexas cirurgias do aparelho digestivo, principalmente quando realizada por técnicas minimamente invasivas. Esse procedimento está associado a inúmeras complicações, como deiscência de anastomose, quilotórax, necrose do tubo gástrico e fistulas. Relatamos o caso de um paciente com o diagnóstico de carcinoma epidermoide no terço distal do esôfago que foi submetido à uma esofagectomia por videotoracoscopia e laparoscopia. Durante o ato operatório, houve lesão do brônquio principal esquerdo, sendo necessária a correção cirúrgica imediata da lesão. No pós-operatório, o paciente evoluiu com insuficiência respiratória aguda e grande escape aéreo pelos drenos de tórax e pela ferida operatória cervical. Foi submetido à nova intervenção cirúrgica, através da qual se observou uma grande lesão na parede membranosa da traqueia, que foi corrigida com um retalho de músculo intercostal.

Esophageal reconstruction is one of the most complex types of gastrointestinal surgery, principally when it is performed using minimally invasive techniques. The procedure is associated with various complications, such as anastomotic dehiscence, chylothorax, esophageal necrosis and fistulae. We report the case of a patient diagnosed with epidermoid carcinoma in the distal third of the esophagus. The patient was submitted to esophagectomy by video-assisted thoracoscopy and laparoscopy. During the operation, the left main bronchus was injured, and this required immediate surgical correction. In the postoperative period, the patient presented with acute respiratory failure and profuse air leak through the thoracic drains and through the cervical surgical wound. The patient underwent a second surgical procedure, during which a large lesion was discovered in the membranous wall of the trachea. The lesion was corrected with an intercostal muscle pedicle flap.

Toracotomía lateral oligotraumática / Lateral oligotraumatic thoracotomy

De las múltiples formas de acceder al tórax sólo muy pocas conservan grupos musculares, permitiendo un acceso amplio a la cavidad torácica. El objetivo de este trabajo es presentar una forma de abordaje del tórax

El colgajo de músculo intercostal en la protección de las suturas traqueobronquiales / Intercostal muscle flap to protect bronchial sutures

Se presenta la experiencia obtenida con el colgajo de músculos intercostales y su pedículo neurovascular intacto como método de protección de 49 suturas bronquiales en resecciones pulmonares; 1 sutura bronquial lateral por fístula esófago-bronquial; 1 sutura de carina por herida de arma de fuego y 2 suturas traqueales durante resecciones esofágicas. El colgajo se confeccionó con y sin resección costal. Los cierres bronquiales fueron ejecutados con sutura mecánica en 49 casos y manual en 1; las suturas de carina y tráquea se ejecutaron también en forma manual. En la serie no hubo ninguna fístula bronquial ni complicaciones atribuíbles al procedimiento

Dehiscencia del muñón bronquial después de neumonectomías / Bronchial stump dehiscence after pneumonectomy

Entre los años 1983 y 1993 se trataron 14 pacientes con dehiscencias del muñón bronquial después de neumonectomías, divididos en dos grupos de acuerdo con el momento de aparición: dehiscencias tempranas (7 casos) y dehiscencias tardías (7 casos). Se describen posibles factores causales: técnicos en el primer grupo e infecciosos en el segundo. La conducta terapéutica, adaptada a cada caso en particular, estuvo orientada al manejo de la insuficiencia respiratoria, el control de la sepsis, el cierre del orificio fistuloso y la reparación de la cavidad residual. Se establecen normas orientadoras para el tratamiento

Infiltracao anestesica em lombotomias. / Anaesthesic infiltration in lombotomies

Em um estudo de 30 pacientes, submetidos a lombotomia, a metade teve infiltracao de cloridrato de bupivacaina, na area dos nervos intercostais e planos musculares, antes do fechamento da ferida operatoria.Nenhuma complicacao foi notada e uma reducao muito intensa da dor foi obtida, com uma diminuicao de 78% no numero de doses de analgesico, em comparacao com grupo controle, no periodo. Outros importantes beneficios obtidos foram: deambulacao com peristaltismo e eliminacao de gases e consequente alimentacao normal mais precoce, respiracao e habilidade para tossir totalmente facilitada, e a depressao dos analgesicos injetaveis foi evitada, de maneira substancial

Modificaciones en la concentración basal de calcio libre mioplasmico inducida por dantroleno sódico en sujetos susceptiblea a hipertermia maligna / Changes in basal myoplasmic free calcium concentration induced bye dantrolene in malignant hyperthermia susceptible patients

La hipertermia maligna (HM) es una miopatia hereditaria la cual se desncadena cuando los individuos susceptibles son expuestos a relajantes musculares despolarizantes y/o potentes anestésicos volátiles halogenados. Hemos estudiado el efecto del dantroleno sobre la concentración intracelular de calcio libre ([Ca2+]i) en biopsias de músuclo intercostal externo obtenidas de: A) tres pacientes susceptibles a HM, antes y después de la administración oral 2,5 mg/Kg durante tres dias, e intravenosa 1,0 mg/Kg dos horas antes de la segunda biopsia de dantroleno sódico, B) de tres pacientes susceptibles a HM antes y después de la administración únicamente intravenosa de dantroleno sódico a una dosis de 1 mg/Kg dos horas antes de la segunda biopsia y C) de dos pacientes susceptibles a HM después de la administración intravenosa de dantroleno sódico 2 mg/Kg dos horas antes de la realización de la segunda biopsia La [Ca2]i libre fue medida medainte microelectrodos selectivos a calcio. El promedio dela [Ca2+]i en fibras musculares provenientes de sujetos susceptibles a HM, antes del tratamiento con dantroleno, fue en el grupo A de 0,42 ñ 0,02 micronM(Promedio ñ SEM), de 0,38 ñ 0,02 micronM en el grupo B, y 0,40 ñ 0,01 micronM en el grupo C. La administración de dantroleno redujo este valor a 0,29 ñ 0,02 micronM, 0,25 ñ0,02 micronM y 0,11 ñ 0,01 en los grupos A, B, y C respectivamente. No hubo diferencias significativas en el potencial de membrana en reposo después del dantroleno. Estos resultados respresentan la primera demostración directa de que el dantroleno puede reducir la [Ca2]i libre en reposo en el músculo esquelético de pacientes susceptibles a la HM, de una manera dosis dpendiente