RESUMO
BACKGROUND: End-tidal P(CO(2)) (Pe'(CO(2))) is routinely used in the clinical assessment of the adequacy of ventilation because it provides an estimate of Pa(CO(2)). How well Pe'(CO(2)) reflects Pa(CO(2)) depends on the gradient between them, expressed as ΔPa-e'(CO(2)). The major determinant of ΔPa-e'(CO(2)) is alveolar dead space (Vd(alv)). The fraction of inspired O(2) (Fi(O(2))) is not thought to substantially affect ΔPa-e'(CO(2)) in anaesthetized patients. We hypothesized that a high Fi(O(2)) may indeed increase ΔPa-e'(CO(2)) by preferentially vasodilating well-perfused alveoli, resulting in the redistribution of blood flow to these alveoli from poorly perfused alveoli and an increase in Vd(alv). We therefore investigated the effects of changes in Fi(O(2)) on ΔPa-e'(CO(2)) and Vd(alv). METHODS: With Institutional Review Board approval and informed consent, we studied 20 ASA I-II supine patients undergoing elective lower abdominal surgery under combined general and epidural anaesthesia. At constant levels of ventilation, Fi(O(2)) levels of 0.21, 0.33, 0.5, 0.75, and 0.97 were applied in a random order and ΔPa-e'(CO(2)) and Vd(alv) were calculated. RESULTS: The ΔPa-e'(CO(2)) values were, in order of ascending Fi(O(2)), {mean [standard error of the mean (SEM)]} 0.13 (0.04), 0.28 (0.08), 0.29 (0.09), 0.44 (0.11), and 0.53 (0.09) kPa. The corresponding values of Vd(alv) were 25.5, 33.8, 35.8, 48.9, and 47.4 ml. Each successive hyperoxic level showed a significant increase in ΔPa-e'(CO(2)) except between the 0.33-0.5 and 0.75-0.97 Fi(O(2)) levels. CONCLUSIONS: These data demonstrate that ΔPa-e'(CO(2)), in anaesthetized patients depends on Fi(O(2)).
Assuntos
Anestesia Geral , Dióxido de Carbono/sangue , Oxigenoterapia , Abdome/cirurgia , Adulto , Idoso , Anestesia Epidural , Feminino , Humanos , Hiperóxia/sangue , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Oxigênio/sangue , Alvéolos Pulmonares/irrigação sanguínea , Circulação Pulmonar , Respiração Artificial , Decúbito Dorsal/fisiologia , Volume de Ventilação Pulmonar/fisiologiaRESUMO
STUDY OBJECTIVE: To better understand the types of chest injuries that are likely to occur following a major earthquake in the urban environment, we analyzed the pattern of chest injuries arising from the earthquake that struck the southern part of Hyogo Prefecture in Japan at 5:46 AM on January 17, 1995 and registered 7.2 on the Richter scale. DESIGN AND SETTING: The medical records of 487 patients with injuries who were referred to Kobe University Hospital from January 17 to January 23 were reviewed. RESULTS: Of the 487 patients, 63 (12.9%) were found to have chest injuries. Of these 63, eight patients with severe chest compression were dead on arrival at the hospital. Eight patients were admitted to our hospital, two of whom developed crush syndrome. The remaining 47 (74.6%) patients had light to moderate injuries and were treated in the emergency department on an outpatient basis. CONCLUSIONS: Minor trauma was the most common type of chest injury. However, there were severely injured patients who were trapped in collapsed buildings.
Assuntos
Desastres , Traumatismos Torácicos/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Japão , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
BACKGROUND: Repair of distal aortic arch aneurysms is difficult to accomplish through a median sternotomy or left thoracotomy, and stroke and respiratory disorders often become lethal complications with the use of circulatory arrest. We investigated the use of retrograde cerebral perfusion with a posterolateral thoracotomy in the repair of distal arch aneurysms. METHODS: Thirty-eight patients underwent repair of a distal arch aneurysm. They were divided into three groups according to the method of surgical repair used. Sixteen patients (group I) underwent proximal anastomosis of the graft with the use of an aortic cross-clamp. Eight patients (group II) underwent open proximal anastomosis with the use of retrograde cerebral perfusion (oxygenated blood perfusion through a superior vena cava cannula) and a median sternotomy and anterolateral thoracotomy. Fourteen patients (group III) also underwent open anastomosis with the use of retrograde cerebral perfusion (cerebral perfusion through blood returned to the right atrium with the patient in the Trendelenburg position) and a posterolateral thoracotomy. RESULTS: The operative mortality rate in group I was 25.0%; 4 of 16 patients died of stroke, myocardial infarction, and intestinal necrosis. In group II, 3 of 8 patients (37.5%) died of respiratory failure and aortic dissection. In group III, only 1 of 14 patients (7.1%) died, as a result of heart failure. CONCLUSIONS: The use of retrograde cerebral perfusion with a posterolateral thoracotomy is an alternative method that minimizes the risk of stroke and respiratory failure during distal aortic arch operations.
Assuntos
Aneurisma da Aorta Torácica/cirurgia , Circulação Cerebrovascular , Toracotomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/métodos , Dissecção Aórtica/etiologia , Implante de Prótese Vascular , Baixo Débito Cardíaco/etiologia , Ponte Cardiopulmonar/efeitos adversos , Causas de Morte , Transtornos Cerebrovasculares/etiologia , Feminino , Parada Cardíaca Induzida/efeitos adversos , Átrios do Coração , Humanos , Intestinos/patologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Necrose , Complicações Pós-Operatórias , Insuficiência Respiratória/etiologia , Fatores de Risco , Taxa de Sobrevida , Toracotomia/efeitos adversos , Veia Cava SuperiorRESUMO
BACKGROUND: In patients with aortic dissection, a patent distal false lumen at long-term follow-up leads to complications. We investigated the feasibility of performing an open distal anastomosis using retrograde cerebral perfusion. METHODS: Over a 10-year period, 41 patients with acute type A aortic dissection underwent 43 surgical repairs. In 1991, an open distal anastomosis using retrograde cerebral perfusion (group 2) was introduced to replace the standard aortic cross-clamp method (group 1). The mean retrograde cerebral perfusion time was 47.3 minutes (range, 22 to 67 minutes), and there were no neurologic sequelae in surviving patients. RESULTS: The operative mortality rate was 18.5% in group 1 and 18.7% in group 2. At long-term follow-up, dilatation of the false lumen (more than 50 mm in diameter) occurred in 9 of 18 patients (50%) in group 1, and 2 patients died of aortic rupture. There were no deaths in group 2, and dilatation of the distal false lumen occurred in only 15.4% of patients (p < 0.05). CONCLUSIONS: The use of retrograde cerebral perfusion in patients with acute aortic dissection provides adequate time to perform a safe, open, distal anastomosis, and could decrease significantly the rate of enlarged, patent, false lumina.
Assuntos
Anastomose Cirúrgica/métodos , Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Circulação Cerebrovascular , Doença Aguda , Adulto , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/patologia , Aneurisma Aórtico/complicações , Aneurisma Aórtico/patologia , Doenças da Aorta/etiologia , Ruptura Aórtica/etiologia , Prótese Vascular , Ponte Cardiopulmonar/métodos , Dilatação Patológica/etiologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Próteses e Implantes , Segurança , Taxa de Sobrevida , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: We describe a simple technique to prevent the lower limb ischemia during femoral veno-arterial cardiopulmonary support (CPS). PATIENTS: Between July 1994 and September 1995, five patients underwent the insertion of femoral veno-arterial CPS with distal limb perfusion for the treatment of circulatory collapse after cardiac surgery. METHODS: After CPS is established, the ipsilateral superficial femoral artery (SFA) is punctured downward with a 14-gauge Teflon catheter and connected to the side port of the membrane oxygenator. RESULTS: None of the patients were complicated by lower limb ischemia for up to 77 hrs on CPS with distal limb perfusion. CONCLUSIONS: Active perfusion through a 14-gauge Teflon catheter downstream to the ipsilateral SFA is effective in preventing lower limb ischemia during prolonged femoral veno-arterial CPS after cardiac surgery.
Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Isquemia/prevenção & controle , Perna (Membro)/irrigação sanguínea , Adulto , Cateterismo , Ponte de Artéria Coronária , Feminino , Artéria Femoral , Veia Femoral , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Humanos , Masculino , Pessoa de Meia-Idade , PerfusãoRESUMO
BACKGROUND: In this paper, we report the surgical results of our DeBakey and Crawford combined method. METHODS: From 1985 to 1995, 22 consecutive patients with thoraco-abdominal aneurysms underwent a modified DeBakey and Crawford combined procedure to minimize the ischemic time for the spinal cord and visceral organs. The extent of aneurysm as classified by Crawford was as follows: Group I, 12; Group II, 4, Group III, 3; Group IV, 3. The etiology of the aneurysm was atherosclerosis in 19, cystic medial necrosis in 2, and aortitis in 1. The aneurysm was approached through the spiral opening method. First, end-to-side distal anastomosis was performed above the bifurcation under partial aortic clamping, and this was followed by proximal anastomosis. During the end-to-end proximal anastomosis, a Gott shunt tube or heparinless left heart bypass was used. In two patients, left renal artery had been previously reconstructed by a saphenous vein graft extending from the left common iliac artery. Then aneurysm was opened, and the right renal artery and superiors mesenteric artery were perfused with cold blood. In two patients, partial cardiopulmonary bypass and selective perfusion were performed. In eight patients, renal artery, celiac artery, superior mesenteric artery, and intercostal artery were reconstructed with a branch graft. RESULTS: No patient died within 30 days of surgery, however, one patient died of acute myocardial infarction (POD 54) and another of ventricular fibrillation during hemodialysis (POD 60). Postoperative complications included paraplegia, and renal failure requiring dialysis each in two patients. Postoperative angiography revealed 18/19 (94.7%) of grafts were patent. CONCLUSIONS: In conclusion, by using different techniques for spinal cord and visceral protection, including the Gott shunt, Biomedicus pump, renal cryopreservation, and separate revascularization of viscera and intercostal arteries, good results could be obtained.
Assuntos
Aneurisma Aórtico/cirurgia , Derivação Cardíaca Esquerda/instrumentação , Isquemia/prevenção & controle , Rim/irrigação sanguínea , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ponte Cardiopulmonar , Feminino , Humanos , Isquemia/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Medula Espinal/irrigação sanguínea , Vísceras/irrigação sanguíneaRESUMO
BACKGROUND: In aortic dissection, patent distal false lumen at long-term follow-up leads to complications. We investigated the feasibility of an open distal anastomosis under retrograde cerebral perfusion. METHODS: During a 15-year period (1981-1995), 51 patients with type A dissection underwent 59 surgical repairs. In 1990, a distal open anastomosis with retrograde cerebral perfusion (group II) was introduced to replace the aortic cross clamp method (group I). Mean retrograde cerebral perfusion time was 50 minutes (range 22 to 65 minutes) with no neurologic sequelae in surviving patients. RESULTS: Operative mortality was 28.6% in group I, and 16.1% in group II. At long-term follow-up, dilatation of the false lumen (more than 50 mm in diameter) occurred in 56.2% (9/16) in group I, and 4 patients died of aortic rupture. There was no mortality in group II, and dilatation of the distal false lumen occurred in only 15.3% (p<0.05). CONCLUSIONS: Use of retrograde cerebral perfusion in aortic dissection allowed for adequate time to perform a safe, open, distal anastomosis. Intraoperative cerebral complications and enlarged patent false lumens decreased significantly.
Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Circulação Cerebrovascular , Parada Cardíaca Induzida/métodos , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Dissecção Aórtica/mortalidade , Aneurisma Aórtico/mortalidade , Doença Crônica , Constrição , Estudos de Viabilidade , Feminino , Humanos , Complicações Intraoperatórias/prevenção & controle , Masculino , Pessoa de Meia-Idade , Perfusão , Estudos Retrospectivos , Análise de SobrevidaRESUMO
BACKGROUND: In the late postoperative period after repair of an aortic dissection or dissecting aneurysm, reoperations may be required. The interval to reoperation, size and location of intimal tear, and results of reoperation were evaluated. METHODS: Between January 1982 and April 1997, 138 patients underwent surgery for Stanford type A (90 patients) or type B (48 patients) dissections of the aorta. The entire aorta was evaluated in postoperative follow-up by computed tomography and magnetic resonance imaging for 6 months to 15 years. Reoperations were performed in 14 (10.1%) patients with changes in the aneurysms at the site of the initial repair or in the distal aorta. Selective cerebral perfusion or retrograde cerebral perfusion with deep hypothermia was used in the repair of the ascending, arch, and distal arch aneurysms. Reoperations included aortic root reconstruction (n=3), resection of a pseudoaneurysm (n=1), and replacement of the ascending aorta (n=1), arch (n=5), descending aorta (n=2), thoracoabdominal aorta (n=1), or abdominal aorta (n=1). Secondary reoperations were performed in four patients (replacement of the arch [n=2], thoracoabdominal aorta and abdominal aorta). Consequently two patients had subtotal aortic replacements. The aneurysms were caused by an anastomotic leak, a new intimal tear following aortic cross-clamping, a second intimal tear in the distal arch or abdominal aorta, and Marfan syndrome. RESULTS: Two patients (2/18 11.1%) died of bleeding or low output syndrome. Two patients died of graft infection or prosthetic valve infection 3 months after surgery respectively. CONCLUSIONS: 1) The surgical results of reoperation for type A and B dissections were good. 2) Close postoperative follow-up of the patent false lumen in the entire aorta was necessary. 3) At the initial operation, total resection of the intimal tear in the aortic arch in low-risk patients reduced the risk of reoperation.
Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Complicações Pós-Operatórias/cirurgia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Adulto , Idoso , Dissecção Aórtica/diagnóstico , Falso Aneurisma/diagnóstico , Falso Aneurisma/mortalidade , Falso Aneurisma/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico , Aneurisma da Aorta Torácica/diagnóstico , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/mortalidade , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/mortalidade , Hemorragia Pós-Operatória/cirurgia , Reoperação/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida , Tomografia Computadorizada por Raios XRESUMO
Twenty-six patients underwent resection and graft replacement of an aortic arch aneurysm (proximal arch,5; transverse arch:2, distal arch,8; and type A dissecting aneurysm. Retrograde cerebral perfusion with pharmacological cerebral protection was carried out during aortic arch aneurysm surgery. Prostaglandin E1, thiopental methylpredonisolone were administered for cerebral protection during core cooling. D-Mannitol and deferoxamine mesylate (radical scavengers) were administered for prevention of reperfusion injury. retrograde cerebral perfusion time was 48 +/- 16 minutes (range 20-80 minutes). Perfusion flow was 288 +/- 93 mL/min (range 150-500 mL/min). Since retrograde cerebral perfusion requires no arterial cannulation or aortic cross clamp, the operative field is simplified, and the risks of air and debris emboli to the brain were minimized. Reconstruction was designed to minimize the circulatory arrest time. Eleven cases underwent emergency surgery due to rupture and acute dissection. Five patients (19.2%) died (three from bleeding from the distal anastomosis, one from postoperative DIC and, one from intraoperative dissection). The remaining 21 patients survived neurologically intact. Retrograde cerebral perfusion with pharmacological cerebral protection is a very simple method to prevent air embolism or thromboembolism in aortic arch aneurysm surgery and allows aortic arch replacement in a bloodless field. In spite of the extended circulatory arrest time, recovery of consciousness was complete.
Assuntos
Aneurisma Aórtico/cirurgia , Encéfalo/irrigação sanguínea , Adulto , Idoso , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Perfusão , Fatores de TempoRESUMO
Twelve consecutive patients requiring surgery for replacement of ascending aortic aneurysms (n = 3), ascending arch aortic aneurysms (n = 2), or type A aortic dissections (n = 7) were treated without aortic cross clamping. Retrograde cerebral perfusion (RCP) with circulatory arrest (mean RCP time: 46.0 +/- 15.9 minutes, range 20 to 65 minutes) and continuous retrograde cardioplegia (mean cardiac ischemic time: 134.4 +/- 39.7 minutes, range: 40 to 180 minutes) were employed. In the patients with aortic dissection, the intimal tear at the origin of the brachiocephalic artery (BCA) was resected completely, the aortic wall was trimmed and closed with Teflon felt. The distal anastomosis was created using an open technique. Air and debris were completely evacuated by returning blood from the cerebral vessels and femoral artery. Then the artificial graft was clamped, and cardiopulmonary bypass resumed. The proximal anastomosis was performed during rewarming. The operations were elective in seven cases, and emergent in five cases. Graft replacement of the ascending aorta was performed in ten patients (including two BCA reconstructions). The remaining two patients were treated by patch repair (n = 1), primary anastomosis (n = 1). There were no perioperative deaths. One patient had a transient neurological deficit. The distal false lumen was occluded completely in five of seven patients with aortic dissections. The other two patients had a secondary tears in the descending aorta. Thus retrograde cerebral perfusion and continuous retrograde cardioplegia without aortic cross clamping is an effective technique in the replacement of the ascending and arch aorta.
Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Parada Cardíaca Induzida/métodos , Perfusão/métodos , Adulto , Idoso , Anastomose Cirúrgica/métodos , Dissecção Aórtica/patologia , Aorta/patologia , Aorta/cirurgia , Aneurisma da Aorta Torácica/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
UNLABELLED: Aggressive surgical treatment in renal cell carcinoma is still controversial. The aim of this paper is to assess inferior vena caval (IVC) reconstruction for suprahepatic vena caval renal cell carcinoma (RCC) tumor thrombus. Twelve patients with suprahepatic vena caval thrombus from renal cell carcinoma who underwent surgical repair with cardiopulmonary bypass were evaluated. The vena caval defect was reconstructed by direct suture, patch repair, or graft replacement. Of 12 patients undergoing partial cardiopulmonary bypass, tumor thrombus extended to the junction of the hepatic vein in three patients and to the right atrium in one. Tumor thrombus was removed manually or with balloon catheter. Tumor thrombus in the right atrium was removed during electrical ventricular fibrillation. Repair of the IVC was performed by direct suture of the IVC wall in two patients, patch repair with expanded polytetrafluoroethylene (EPTFE) graft in seven, and graft replacement with an EPTFE graft in three. There were no operative deaths and the only postoperative complication was one patient death from pulmonary emboli. The four patients with nonlocalized disease died within 2 years, but four patients lived for more than 3 years postoperatively. Survival was 37.5% at 3 years and 18.8% at 5 years by the Kaplan-Meier's method. CONCLUSIONS: (1) Partial cardiopulmonary bypass is useful for the control of bleeding when tumor thrombus in the IVC extends to the junction of the hepatic vein. (2) Nephrectomy with tumor thrombectomy of the IVC is valuable, and long-term survival is possible in patients without distant metastases or regional lymph node metastases.
Assuntos
Carcinoma de Células Renais/complicações , Ponte Cardiopulmonar , Neoplasias Renais/complicações , Trombose/cirurgia , Veia Cava Inferior/patologia , Veia Cava Inferior/cirurgia , Adulto , Idoso , Implante de Prótese Vascular , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Feminino , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Resultado do TratamentoRESUMO
We report the 7th known case in the literature of cardiac angiosarcoma resulting in cardiac rupture. A 34-year-old woman was admitted presenting chest pain and pericardial effusion. After the patient had been treated for 3 months under the diagnosis of pericarditis of unknown etiology, she became hypotensive. Doppler echocardiography showed increased pericardial effusion and a communication between the right atrium and the pericardial cavity. An emergency operation was undertaken to drain the effusion and explore the etiology. We found the ruptured right atrium and the irregularly shaped tumor extending from the pericardium near the inferior caval vein to the right ventricle. There was no apparent tumor on the right atrium, but its wall was extensively thin, which we replaced with autologous pericardium. The patient died on the 44th postoperative day. Clinical diagnosis of cardiac angiosarcoma is usually very difficult. If Doppler echocardiography demonstrates pericardial effusion and find a ruptured right atrium with or without mass formation, we should suspect cardiac angiosarcoma.
Assuntos
Neoplasias Cardíacas/complicações , Ruptura Cardíaca/etiologia , Hemangiossarcoma/complicações , Adulto , Feminino , Átrios do Coração , Neoplasias Cardíacas/diagnóstico por imagem , Hemangiossarcoma/diagnóstico por imagem , Humanos , Derrame Pericárdico/etiologia , UltrassonografiaRESUMO
A 76-year-old man admitted to one hospital complaining of transient left hemiparesis. Because of arrhythmia, he was examined by an echocardiogram and found to have an oval free-floating thrombus in his left atrium concomitant with mitral stenosis. He was transferred to our hospital for emergency surgery. On operation, a 3 x 4 cm ball thrombus was removed and diseased mitral valve was replaced with a SJM prosthetic valve. His postoperative course was relatively uneventful. Though left atrial ball thrombus is rarely found among the patients with mitral valve disease, when left atrial ball thrombus is found, immediate surgical intervention is recommended to avoid sudden death.
Assuntos
Cardiopatias/cirurgia , Trombose/cirurgia , Átrios do Coração , Cardiopatias/complicações , Próteses Valvulares Cardíacas , Humanos , Masculino , Valva Mitral/cirurgia , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/cirurgia , Trombose/complicaçõesRESUMO
Since 1991, 27 consecutive patients with aortic dissection (Stanford A) have been operated on using deep hypothermic retrograde cerebral perfusion (RCP). There were no differences in ECC time (247 +/- 15 vs 307 +/- 22 min), and RCP time (47 +/- 2 vs 47 +/- 3 min) between the aged (> or = 70 y.o., n = 11) and non-aged (< 70 y.o., n = 16) group. Although the aged group showed the higher incidences of postoperative neurological complications of prolonged emergence (2 cases) and delirium (3 cases), respiratory disorder (3 cases), and renal dysfunction (3 cases), there was no significant difference in hospital mortality (18% in the aged vs 13% in the non-aged). We concluded that RCP is well acceptable procedure for surgical treatment of the aged patients with aortic dissection.
Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Circulação Extracorpórea/métodos , Hipertermia Induzida , Fatores Etários , Idoso , Prótese Vascular , Feminino , Humanos , Masculino , Perfusão , Estudos Retrospectivos , Resultado do TratamentoRESUMO
A monitoring system for tracking the electromyogram (EMG) of the vocal cords with wire electrodes embedded in an endotracheal tube was designed to identify the recurrent laryngeal nerve during thyroidectomy. Our recent experience in two cases suggests that vagal nerve activity can be correctly detected by recording of the EMG of the vocal cords using a special endotracheal tube embedded with wire electrodes.
Assuntos
Neoplasias do Tronco Encefálico/cirurgia , Eletrodos , Monitorização Intraoperatória , Nervo Vago/fisiologia , Adulto , Criança , Craniotomia , Eletromiografia , Feminino , Humanos , Resultado do Tratamento , Nervo Vago/fisiopatologiaRESUMO
Anaesthesiologists have traditionally been consulted to help design breathing circuits to attain and maintain target end-tidal carbon dioxide (P(ET)CO2). The methodology has recently been simplified by breathing circuits that sequentially deliver fresh gas (not containing carbon dioxide (CO2)) and reserve gas (containing CO2). Our aim was to determine the roles of fresh gas flow, reserve gas PCO2 and minute ventilation in the determination of P(ET)CO2. We first used a computer model of a non-rebreathing sequential breathing circuit to determine these relationships. We then tested our model by monitoring P(ET)CO2 in human volunteers who increased their minute ventilation from resting to five times resting levels. The optimal settings to maintain P(ET)CO2 independently of minute ventilation are 1) fresh gas flow equal to minute ventilation minus anatomical deadspace ventilation, and 2) reserve gas PCO2 equal to alveolar PCO2. We provide an equation to assist in identifying gas settings to attain a target PCO2. The ability to precisely attain and maintain a target PCO2 (isocapnia) using a sequential gas delivery circuit has multiple therapeutic and scientific applications.
Assuntos
Anestesia com Circuito Fechado/métodos , Dióxido de Carbono/sangue , Espaço Morto Respiratório/fisiologia , Gasometria , Estudos de Casos e Controles , Feminino , Humanos , Hipercapnia/prevenção & controle , Hipocapnia/prevenção & controle , Masculino , Monitorização Fisiológica , Probabilidade , Troca Gasosa Pulmonar , Valores de Referência , Respiração Artificial , Mecânica Respiratória , Sensibilidade e Especificidade , Volume de Ventilação PulmonarRESUMO
OBJECTIVE: One hundred percent oxygen is given in pregnancy to improve fetal oxygenation, yet has been shown in both animal and human studies ex utero to increase cerebral vascular resistance. Adjusting end-tidal pCO2 (ET-pCO2) levels to normocapnic levels during hyperoxygenation offsets this effect in non-pregnant individuals. We aimed to evaluate the effect of maternal hyperoxygenation with and without maintaining normocapnia on the fetal and uteroplacental circulations in healthy near-term human pregnancies. METHODS: Eight healthy pregnant women, serving as their own controls, sequentially breathed room air, breathed 100% oxygen, and underwent normocapnic hyperoxygenation (NH) in a three-phase experiment involving a tight-fitting facemask. Each phase lasted 10-15 min. After steady state had been reached, peak velocities and pulsatility index (PI) values were obtained from the uterine, umbilical and fetal middle cerebral arteries (MCA) by color/pulsed Doppler. In addition, maternal ventilation and ET-pCO2 were monitored. RESULTS: One hundred percent oxygen induced maternal hyperventilation and hypocapnea. Uterine artery PI and peak systolic velocities were stable during 100% oxygen. In contrast, during NH uterine artery PI values decreased by 21% (P=0.04). Umbilical artery PI and peak velocities were stable during 100% oxygen; PI increased by 16% during NH (P=0.056), with no change in peak velocities. Peak MCA velocities decreased by 8% during 100% oxygen, and by 9.6% during NH, while MCA-PI decreased by 13% during 100% oxygen and by 21% during NH (P=0.06). CONCLUSIONS: Maternal and fetal circulations exhibit divergent responses to 100% oxygen and NH. While no change is observed in the uteroplacental circulation on 100% oxygen, decreased resistance and increased flow velocity are evident during NH. Increased umbilical artery PI during NH with no change in absolute velocities may suggest a reduction in fetoplacental blood flow. Maintaining normocapnia during hyperoxygenation does not appear to beneficially influence the circulation of the near-term human fetus as it does in non-pregnant individuals.
Assuntos
Hiperóxia/diagnóstico por imagem , Oxigenoterapia , Circulação Placentária , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal/métodos , Útero/irrigação sanguínea , Adulto , Artérias/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , Dióxido de Carbono/sangue , Estudos de Casos e Controles , Feminino , Humanos , Hiperóxia/sangue , Hiperóxia/fisiopatologia , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/embriologia , Gravidez , Estatísticas não Paramétricas , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler de Pulso , Artérias Umbilicais/diagnóstico por imagem , Resistência Vascular/efeitos dos fármacosRESUMO
Since 1987, 33 patients have undergone surgery at Kobe University Hospital for aneurysm of the descending aorta using left heart bypass with a heparin-coated centrifugal pump and heparin-coated tubes. Sixteen patients had true aneurysms of the descending thoracic aorta, 7 had thoracoabdominal aneurysms, and 10 had aortic dissection (DeBakey's Type III). Heat exchangers and oxygenators were not included in the bypass circuit in any of the cases. Perfusion time was from 42 to 205 min (average 90 min). Left heart bypass was established with 1 mg/kg of systemic heparinization in 5 cases, 0.5 mg/kg in 5 cases, and 0 mg/kg in 23 cases. There were no complications such as perioperative embolism, acidosis, or hypothermia. During aortic cross-clamping, the arterial pressure of the lower extremity was maintained above 70 mm Hg, but there was no relationship between the distal perfusion pressure and bypass flow. The urine output during left heart bypass was related to the distal perfusion flow by centrifugal pump. Of 23 patients who underwent bypass with less than 40 ml/kg/min of distal perfusion flow, 7 showed transient renal dysfunction postoperatively, and 1 developed postoperative renal failure. The other patients who were bypassed with over 40 ml/kg/min of pump flow stayed in the normal range of renal function. Postoperative paresis occurred in 2 patients, who were also perfused with less than 40 ml/kg/min of bypass flow. It could be concluded that left heart bypass by centrifugal pump is safe and acceptable as a circulatory support in the surgical treatment of aneurysm of the descending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Aneurisma da Aorta Torácica/cirurgia , Coração Auxiliar , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
Since 1987, 33 patients were operated on for aneurysm of the descending thoracic aorta using temporary bypass with a heparin-coated centrifugal pump and heparin-coated tubes at Kobe University Hospital. Sixteen patients had true aneurysms of the descending thoracic aorta, 7 had thoraco-abdominal aneurysms and 10 had aortic dissection (DeBakey's type III). Heat exchanger and oxygenator were not included in the bypass circuit in all cases. Perfusion time was from 42 to 205 minutes (average 90 minutes). Left heart bypass was established with 1 mg/kg of systemic heparinization in 5, 0.5 mg/kg in 5, and 0 mg/kg in 23 cases. There were no complications such as perioperative embolism, acidosis, or hypothermia. During aortic cross-clamping, the arterial pressure of the lower extremity was maintained over 70 mmHg, but there was no relationship between the distal perfusion pressure and bypass flow. The urine output during temporary bypass was significantly related to the distal perfusion flow by centrifugal pump (r = 0.455, p < 0.01). Seven out of 23 patients who were bypassed under 40 ml/kg/min of distal perfusion flow showed transient renal dysfunction postoperatively, and two developed postoperative renal failure, while the other patients bypassed over 40 ml/kg/min of pump flow stayed in the normal range of the renal function, where there were statistically differences (p < 0.05). Postoperative paresis occurred in 2 patients who were also perfused under 40 ml/kg/min of bypass flow. Therefore, it is concluded that temporary bypass with centrifugal pump is a safe and well acceptable circulatory support in the surgical treatment of aneurysm of the descending aorta.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Circulação Assistida , Prótese Vascular , Circulação Extracorpórea , Adulto , Idoso , Idoso de 80 Anos ou mais , Circulação Assistida/métodos , Centrifugação , Circulação Extracorpórea/métodos , Feminino , Humanos , Isquemia/prevenção & controle , Rim/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medula Espinal/irrigação sanguíneaRESUMO
A 73-year-old female complaining of left thoracic pain was referred to our hospital. In 1988, she had the first CABG of the left circumflex coronary artery (CX) and right coronary artery. On admission in April 1994, chest X-ray and CT scan revealed a saccular aortic aneurysm, 5 x 5 cm in size, extending to the distal to the left subclavian artery. Coronary arteriography showed a patency of the CX graft, but 99% stenosis of the proximal left anterior descending branch (LAD) with delayed opacification. After the repeated median sternotomy, cardiac arrest was achieved with the aortic cross clamping and St. Thomas Hospital solution infusion. CABG to the LAD branch using a saphenous vein was accomplished. Following this, the replacement of the aortic aneurysmal lesion with a prosthetic graft was performed under the selective cerebral perfusion with deep hypothermia. Proximal anastomosis of the vein graft was completed during a rewarming period. The operation was performed without complications. Postoperative course was satisfactory except a few minor transient complications such as athelectasis of the left upper lobe and the intra-thoracic hematoma. After one month's hospitalization, she was discharged, and currently (six months postoperative) remains asymptomatic.