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1.
Diagn Interv Radiol ; 21(4): 327-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26081719

RESUMO

PURPOSE: We aimed to compare clinical outcomes and early adverse events of operative management (OM), nonoperative management (NOM), and NOM with splenic artery embolization (SAE) in blunt splenic injury (BSI) and identify the prognostic factors. METHODS: Medical records of 136 consecutive patients with BSI admitted to a trauma center from 2005 to 2010 were retrospectively reviewed. Patients were separated into three groups: OM, NOM, and SAE. We focused on associated injuries and early adverse events. Multivariate analysis was performed on 23 prognostic factors to find predictors. RESULTS: The total survival rate was 97.1%, with four deaths all occurred in the OM group. The spleen salvage rate was 91% in NOM and SAE. At least one adverse event was observed in 32.8%, 62%, and 96% of patients in NOM, SAE, and OM groups, respectively (P < 0.001). We found significantly more deaths, infectious complications, pleural drainage, acute renal failures, and pancreatitis in OM and more pseudocysts in SAE. Six prognostic factors were statistically significant for one or more adverse events: simplified acute physiology score 2 ≥25 for almost all adverse events, age ≥50 years for acute respiratory syndrome, limb fracture for secondary bleeding, thoracic injury for pleural drainage, and at least one associated injury for pseudocyst. Adverse events were not related to the type of BSI management. CONCLUSION: Patients with BSI present worse outcome and more adverse events in OM, but this is related to the severity of injury. The main predictor of adverse events remains the severity of injury.


Assuntos
Embolização Terapêutica/métodos , Baço/lesões , Baço/cirurgia , Ferimentos não Penetrantes/patologia , Ferimentos não Penetrantes/terapia , Adulto , Gerenciamento Clínico , Embolização Terapêutica/efeitos adversos , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Prognóstico , Estudos Retrospectivos , Baço/patologia , Taxa de Sobrevida , Resultado do Tratamento , Ferimentos não Penetrantes/cirurgia , Adulto Jovem
2.
Injury ; 45(1): 101-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23845571

RESUMO

BACKGROUND: The early diagnosis of pelvic arterial haemorrhage is challenging for initiating treatment by transcatheter arterial embolization (TAE) in multiple trauma patients. We use an institutional algorithm focusing on haemodynamic status on admission and on a whole-body CT scan in stabilized patients to screen patients requiring TAE. This study aimed to assess the effectiveness of this approach. METHODS: This retrospective cohort study included 106 multiple trauma patients admitted to the emergency room with serious pelvic fracture [pelvic abbreviated injury scale (AIS) score of 3 or more]. RESULTS: Of the 106 patients, 27 (25%) underwent pelvic angiography leading to TAE for active arterial haemorrhage in 24. The TAE procedure was successful within 3h of arrival in 18 patients. In accordance with the algorithm, 10 patients were directly admitted to the angiography unit (n=8) and/or operating room (n=2) for uncontrolled haemorrhagic shock on admission. Of the remaining 96 stabilized patients, 20 had contrast media extravasation on pelvic CT scan that prompted pelvic angiography in 16 patients leading to TAE in 14. One patient underwent a pelvic angiography despite showing no contrast media extravasation on pelvic CT scan. All 17 stabilized patients who underwent pelvic angiography presented a more severely compromised haemodynamic status on admission, and they required more blood products during their initial management than the 79 patients who did not undergo pelvic angiography. The incidence of unstable pelvic fractures was however comparable between the two groups. Overall, haemodynamic instability and contrast media extravasation on the CT-scan identified 26 out of the 27 patients who required subsequent pelvic angiography leading to TAE in 24. CONCLUSIONS: An algorithm focusing on haemodynamic status on arrival and on the whole-body CT scan in stabilized patients may be effective at triaging multiple trauma patients with serious pelvic fractures.


Assuntos
Embolização Terapêutica , Fraturas Ósseas/diagnóstico por imagem , Hemorragia/diagnóstico , Traumatismo Múltiplo/diagnóstico por imagem , Ossos Pélvicos/lesões , Choque Hemorrágico/prevenção & controle , Tomografia Computadorizada por Raios X , Escala Resumida de Ferimentos , Adulto , Algoritmos , Angiografia , Estudos de Coortes , Feminino , Fraturas Ósseas/complicações , Fraturas Ósseas/terapia , Hemorragia/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/terapia , Estudos Retrospectivos , Choque Hemorrágico/diagnóstico por imagem
3.
Intensive Care Med ; 39(9): 1535-46, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23740278

RESUMO

PURPOSE: Septic shock is a leading cause of death among critically ill patients, in particular when complicated by acute kidney injury (AKI). Small experimental and human clinical studies have suggested that high-volume haemofiltration (HVHF) may improve haemodynamic profile and mortality. We sought to determine the impact of HVHF on 28-day mortality in critically ill patients with septic shock and AKI. METHODS: This was a prospective, randomized, open, multicentre clinical trial conducted at 18 intensive care units in France, Belgium and the Netherlands. A total of 140 critically ill patients with septic shock and AKI for less than 24 h were enrolled from October 2005 through March 2010. Patients were randomized to either HVHF at 70 mL/kg/h or standard-volume haemofiltration (SVHF) at 35 mL/kg/h, for a 96-h period. RESULTS: Primary endpoint was 28-day mortality. The trial was stopped prematurely after enrolment of 140 patients because of slow patient accrual and resources no longer being available. A total of 137 patients were analysed (two withdrew consent, one was excluded); 66 patients in the HVHF group and 71 in the SVHF group. Mortality at 28 days was lower than expected but not different between groups (HVHF 37.9 % vs. SVHF 40.8 %, log-rank test p = 0.94). There were no statistically significant differences in any of the secondary endpoints between treatment groups. CONCLUSIONS: In the IVOIRE trial, there was no evidence that HVHF at 70 mL/kg/h, when compared with contemporary SVHF at 35 mL/kg/h, leads to a reduction of 28-day mortality or contributes to early improvements in haemodynamic profile or organ function. HVHF, as applied in this trial, cannot be recommended for treatment of septic shock complicated by AKI.


Assuntos
Injúria Renal Aguda/complicações , Hemofiltração/métodos , Choque Séptico/complicações , Choque Séptico/terapia , Injúria Renal Aguda/mortalidade , Idoso , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque Séptico/mortalidade , Taxa de Sobrevida , Fatores de Tempo
5.
Chest ; 141(5): 1177-1183, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22016490

RESUMO

BACKGROUND: The accuracy of combined clinical examination (CE) and chest radiography (CXR) (CE + CXR) vs thoracic ultrasonography in the acute assessment of pneumothorax, hemothorax, and lung contusion in chest trauma patients is unknown. METHODS: We conducted a prospective, observational cohort study involving 119 adult patients admitted to the ED with thoracic trauma. Each patient, secured onto a vacuum mattress, underwent a subsequent thoracic CT scan after first receiving CE, CXR, and thoracic ultrasonography. The diagnostic performance of each method was also evaluated in a subgroup of 35 patients with hemodynamic and/or respiratory instability. RESULTS: Of the 237 lung fields included in the study, we observed 53 pneumothoraces, 35 hemothoraces, and 147 lung contusions, according to either thoracic CT scan or thoracic decompression if placed before the CT scan. The diagnostic performance of ultrasonography was higher than that of CE + CXR, as shown by their respective areas under the receiver operating characteristic curves (AUC-ROC): mean 0.75 (95% CI, 0.67-0.83) vs 0.62 (0.54-0.70) in pneumothorax cases and 0.73 (0.67-0.80) vs 0.66 (0.61-0.72) for lung contusions, respectively (all P < .05). In addition, the diagnostic performance of ultrasonography to detect pneumothorax was enhanced in the most severely injured patients: 0.86 (0.73-0.98) vs 0.70 (0.61-0.80) with CE + CXR. No difference between modalities was found for hemothorax. CONCLUSIONS: Thoracic ultrasonography as a bedside diagnostic modality is a better diagnostic test than CE and CXR in comparison with CT scanning when evaluating supine chest trauma patients in the emergency setting, particularly for diagnosing pneumothoraces and lung contusions.


Assuntos
Traumatismos Torácicos/diagnóstico por imagem , Adulto , Estudos de Coortes , Contusões/diagnóstico por imagem , Feminino , Hemodinâmica/fisiologia , Hemotórax/diagnóstico por imagem , Humanos , Lesão Pulmonar/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Exame Físico , Pneumotórax/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Prospectivos , Radiografia Torácica , Sensibilidade e Especificidade , Espanha , Tomografia Computadorizada por Raios X , Centros de Traumatologia , Ultrassonografia , Adulto Jovem
6.
Crit Care Med ; 40(1): 29-35, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21926601

RESUMO

OBJECTIVE: To investigate the effects of moderate-dose hydrocortisone on hemodynamic status in critically ill patients throughout the period of etomidate-related adrenal insufficiency. DESIGN: : Randomized, controlled, double-blind trial (NCT00862381). SETTING: University hospital emergency department and three intensive care units. INTERVENTIONS: After single-dose etomidate (H0) for facilitating endotracheal intubation, patients without septic shock were randomly allocated at H6 to receive a 42-hr continuous infusion of either hydrocortisone at 200 mg/day (HC group; n = 49) or saline serum (control group; n = 50). MEASUREMENTS AND MAIN RESULTS: After completion of a corticotrophin stimulation test, serum cortisol and 11ß-deoxycortisol concentrations were subsequently assayed at H6, H12, H24, and H48. Forty-eight patients were analyzed in the HC group and 49 patients in the control group. Before treatment, the diagnostic criteria for etomidate-related adrenal insufficiency were fulfilled in 41 of 45 (91%) and 38 of 45 (84%) patients in the HC and control groups, respectively. The proportion of patients with a cardiovascular Sequential Organ Failure Assessment score of 3 or 4 declined comparably over time in both HC and control groups: 65% vs. 67% at H6, 65% vs. 69% at H12, 44% vs. 54% at H24, and 34% vs. 45% at H48, respectively. Required doses of norepinephrine decreased at a significantly higher rate in the HC group compared with the control group in patients treated with norepinephrine at H6. No intergroup differences were found regarding the duration of mechanical ventilation, intensive care unit length of stay, or 28-day mortality. CONCLUSION: These findings suggest that critically ill patients without septic shock do not benefit from moderate-dose hydrocortisone administered to overcome etomidate-related adrenal insufficiency.


Assuntos
Insuficiência Adrenal/prevenção & controle , Anestésicos Intravenosos/efeitos adversos , Estado Terminal/terapia , Etomidato/efeitos adversos , Hidrocortisona/uso terapêutico , Insuficiência Adrenal/induzido quimicamente , Adulto , Método Duplo-Cego , Feminino , Humanos , Hidrocortisona/administração & dosagem , Hidrocortisona/sangue , Infusões Intravenosas , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
7.
Intensive Care Med ; 36(9): 1514-20, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20490780

RESUMO

PURPOSE: The early diagnosis of traumatic internal carotid artery dissection (TICAD) is essential for initiating appropriate treatment and improving outcome. We searched for criteria from transcranial Doppler (TCD) measurements on admission that could be associated with subsequent TICAD diagnosis in patients with traumatic brain injury (TBI). METHODS: We conducted a retrospective 1:4 matched (age, mean arterial blood pressure) cohort study of 11 TBI patients with TICAD and absent or mild brain lesions on initial CT scan, 22 TBI controls with comparable brain CT scan lesions (controls 1), and 22 TBI controls with more severe brain CT scan lesions (controls 2) on admission. TCD measurements were obtained on admission from both middle cerebral arteries (MCA). All patients had subsequent CT angiography to diagnose TICAD. RESULTS: A >25% asymmetry in the systolic blood flow velocity between the two MCA was found in 9/11 patients with TICAD versus 0/22 in controls 1 and 5/22 in controls 2 (p < 0.01). The combination of this asymmetry with an ipsilateral pulsatility index < or =0.80 was found in 9/11 patients with TICAD versus none in the two groups of controls (p < 0.01). CONCLUSIONS: Our results suggest that significant asymmetry in the systolic blood flow velocity between the MCAs and a reduced ipsilateral pulsatility index could be criteria from TCD measurements associated with the occurrence of TICAD in head-injured patients. If prospectively validated, these findings could be incorporated in screening protocols for TICAD in patients with TBI.


Assuntos
Lesões Encefálicas/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Artéria Cerebral Média/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Adolescente , Adulto , Idoso , Lesões Encefálicas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/patologia , Fluxo Pulsátil , Estudos Retrospectivos , Fatores de Risco , Índices de Gravidade do Trauma , Ultrassonografia de Intervenção , Adulto Jovem
8.
J Trauma ; 68(4): 942-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20173661

RESUMO

OBJECTIVE: The purpose of this study was to describe a blinded intra-aortic balloon occlusion (IABO) procedure in pelvic fractures (PF) for patients with critically uncontrollable hemorrhagic shock (CUHS). METHODS: Of 2,064 patients treated for PF, 13 underwent IABO during initial resuscitation to control massive pelvic bleeding leading to CUHS. Our IABO procedure consists of internal aortic occlusion without fluoroscopy, using a latex balloon inflated in the infrarenal aorta. Retrospectively collected data included demographics, fracture classification, additional injuries, blood transfusions, surgical interventions, angiographic procedure, physiologic parameters, and survival. RESULTS: All balloons were successfully placed, and a significant increase in systolic blood pressure (70 mm Hg, p = 0.001) was observed immediately after IABO. Twelve of 13 patients became transferrable. Angiography performed after IABO was positive for arterial injury in 92% of patients, and 9 patients benefitted from arterial embolization. Survival rate was 46% (6 of 13) and was inversely related to the length of inflation (p = 0.026) and the mean Injury Severity Score (p = 0.011). CONCLUSION: This IABO procedure can be life saving in the management of patients with CUHS from PF, permitting transport to angiography. However, the decision for such treatment must be as quickly as possible after trauma to reduce the time of occlusion.


Assuntos
Aorta Abdominal , Oclusão com Balão/métodos , Fraturas Ósseas/complicações , Ossos Pélvicos/lesões , Ossos Pélvicos/cirurgia , Terapia de Salvação , Choque Hemorrágico/terapia , Adulto , Angiografia , Transfusão de Sangue/estatística & dados numéricos , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Estudos Retrospectivos , Choque Hemorrágico/etiologia , Taxa de Sobrevida , Resultado do Tratamento
9.
Cardiovasc Intervent Radiol ; 31(5): 875-82, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18247088

RESUMO

This study evaluates the efficacy of arterial embolization (AE) for blunt hepatic traumas (BHT) as part of a combined management strategy based on the hemodynamic status of patients and CT findings. From 2000 to 2005, 84 patients were admitted to our hospital for BHT. Of these, 14 patients who had high-grade injuries (grade III [n = 2], grade IV [n = 9], grade V [n = 3]) underwent AE because of arterial bleeding and were included in the study. They were classified into three groups according to their hemodynamic status: (1) unresponsive shock, (2) shock improved with resuscitation, and (3) hemodynamic stability. Four patients (group 1) underwent, first, laparotomy with packing and, then, AE for persistent bleeding. Ten patients who were hemodynamically stable (group 1) or even unstable (group 2) underwent AE first, based on CT findings. AE was successful in all cases. The mortality rate was 7% (1/14). Only two angiography-related complications (gallbladder infarction) were reported. Liver-related complications (abdominal compartment syndrome and biliary complications) were frequent and often required secondary interventions. Our multidisciplinary approach for the management of BHT gives a main role to embolization, even for hemodynamically unstable patients. In this strategy AE is very efficient and has a low complication rate.


Assuntos
Angiografia/métodos , Embolização Terapêutica/métodos , Fígado/lesões , Ferimentos não Penetrantes/mortalidade , Ferimentos não Penetrantes/terapia , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Terapia Combinada , Feminino , Hidratação/métodos , Seguimentos , Hemodinâmica/fisiologia , Artéria Hepática/diagnóstico por imagem , Humanos , Escala de Gravidade do Ferimento , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista , Ressuscitação/métodos , Estudos Retrospectivos , Medição de Risco , Taxa de Sobrevida , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Ferimentos não Penetrantes/diagnóstico por imagem , Adulto Jovem
10.
World J Surg ; 32(6): 1189-93, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18259808

RESUMO

BACKGROUND: Nonoperative management (NOM) is considered standard treatment for 80% of blunt hepatic trauma (BHT). NOM is associated with some events that may require delayed operation (DO), usually considered a criterion of failure of NOM. METHODS: A retrospective case note review was performed on 257 consecutive patients with BHT, with a median age of 32.7 years, admitted from 1994 to 2005. We considered the 186 patients (72%) who had an initial indication of NOM, and focused on the 28 patients who were secondarily operated (DO), mainly on the 22 patients operated on for liver-related indications. Celioscopy was used in five cases. RESULTS: The severity grade of these 22 patients was: zero grade I, seven grade II, ten grade III, four grade IV, one grade V. The timing of DO varied from day 0 to day 11. Ten patients were operated on for a peritoneal inflammatory syndrome. Death occurred in three patients at days 2, 10, and 125. One was attributed to underestimation of hepatic necrosis, another to a nondiagnosed peritoneal inflammatory syndrome; 27, 3% of the patients had liver-related complications. CONCLUSIONS: Our data suggest that BHT treated by NOM must be frequently reevaluated and that DO is an actual part of the so-called nonoperative treatment. The use of laparoscopic washing has to be proposed as soon as day 3 or 5 in patients with large hemoperitoneum and any sign of inflammatory response (fever, leukocytosis, discomfort, tachycardia).


Assuntos
Laparoscopia , Laparotomia , Fígado/lesões , Ferimentos e Lesões/cirurgia , Adulto , Humanos , Lavagem Peritoneal , Peritonite/diagnóstico , Peritonite/etiologia , Estudos Retrospectivos , Ferimentos e Lesões/terapia
11.
Intensive Care Med ; 34(4): 714-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18092151

RESUMO

OBJECTIVE: To determine the incidence and duration of adrenal inhibition induced by a single dose of etomidate in critically ill patients. DESIGN: Prospective, observational cohort study. SETTING: Three intensive care units in a university hospital. PATIENTS: Forty critically ill patients without sepsis who received a single dose of etomidate for facilitating endotracheal intubation. MEASUREMENTS AND MAIN RESULTS: Serial serum cortisol and 11beta-deoxycortisol samples were taken at baseline and 60 min after corticotropin stimulation test (250 microg 1-24 ACTH) at 12, 24, 48, and 72 h after etomidate administration. Etomidate-related adrenal inhibition was defined by the combination of a rise in cortisol less than 250 nmol/l (9 microg/dl) after ACTH stimulation and an excessive accumulation of serum 11beta-deoxycortisol concentrations at baseline. At 12 h after etomidate administration, 32/40 (80%) patients fulfilled the diagnosis criteria for etomidate-related adrenal insufficiency. This incidence was significantly lower at 48 h (9%) and 72 h (7%). The cortisol to 11beta-deoxycortisol ratio (F/S ratio), reflecting the intensity of the 11beta-hydroxylase enzyme blockade, improved significantly over time. CONCLUSIONS: A single bolus infusion of etomidate resulted in wide adrenal inhibition in critically ill patients. However, this alteration was reversible by 48 h following the drug administration. The empirical use of steroid supplementation for 48 h following a single dose of etomidate in ICU patients without septic shock should thus be considered. Concomitant serum cortisol and 11beta-deoxycortisol dosages are needed to provide evidence for adrenal insufficiency induced by etomidate in critically ill patients.


Assuntos
Insuficiência Adrenal/induzido quimicamente , Anestésicos Intravenosos/efeitos adversos , Etomidato/efeitos adversos , Intubação Intratraqueal , Testes de Função do Córtex Suprarrenal , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestésicos Intravenosos/farmacocinética , Estado Terminal , Etomidato/farmacocinética , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Intensive Care Med ; 32(5): 770-4, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16550373

RESUMO

OBJECTIVE: To compare surgical and endovascular stent graft (ESG) treatment of blunt thoracic aortic injury (BAI) in the emergency setting. DESIGN AND SETTING: Retrospective case control study in two surgical intensive care units of a university hospital. PATIENTS: 30 patients who presented with BAI between 1995 and 2005: 17 treated surgically and 13 by ESG. The two groups were comparable for the severity of trauma and mean delay before treatment; the mean age was higher in the ESG group (46+/-18 vs. 35+/-15 years). RESULTS: In the surgical group time spent in the operating theater was longer (310+/-130 vs. 140+/-48 min) and blood losses higher (2000+/-1300 vs. no significant bleeding); aortic clamping time was 48+/-20 min. The mortality rate was 15% with ESG (n=2) and 23% with surgery (n=4). Complications of the procedure were more frequent in the surgical group (1 vs. 7). In the ESG group there was one pulmonary embolism. In the surgical group there were three neurological complications, one acute aortic dissection, one perioperative rupture, one periprosthetic leak, and one septic shock. Two complications (postoperative aortic dissection and paraplegia) appeared in the same patient in the surgical group. Intensive care unit length of stay, duration of mechanical ventilation, and catecholamine support were similar in the two groups. CONCLUSIONS: Stent graft for emergency treatment of BAI is efficient and is associated with fewer complications than surgical treatment.


Assuntos
Implante de Prótese Vascular , Serviços Médicos de Emergência , Stents , Artérias Torácicas/lesões , Ferimentos não Penetrantes/cirurgia , Adulto , Feminino , França , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Artérias Torácicas/cirurgia
13.
Anesth Analg ; 95(6): 1746-51, table of contents, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12456451

RESUMO

UNLABELLED: Sustained hyperventilation has a time-limited effect on cerebrovascular dynamics. We investigated whether this effect was similar among brain regions by measuring regional cerebral blood volume (CBV) with steady-state susceptibility contrast magnetic resonance imaging during 3 h of hyperventilation. Regional CBV was determined in nine thiopental-anesthetized, mechanically-ventilated rats every 30 min in the dorsoparietal neocortex, the corpus striatum, and the cerebellum. The corpus striatum was the only brain region showing a stable reduction in CBV during the hypocapnic episode (PaCO(2), 24 +/- 3 mm Hg). In contrast, neocortex and, to a lesser extent, cerebellum exhibited a progressive return toward normal values despite continued hypocapnia. No evidence of a rebound in CBV was found on return to normal ventilation in the three brain regions. We conclude that sustained hyperventilation can lead to an uneven change in the reduction of CBV, possibly because of differences of brain vessels in their sensitivity to extracellular pH. Our results in neocortex confirm the transient effect of sustained hyperventilation on cerebral hemodynamics. IMPLICATIONS: Sustained hyperventilation has a transient effect in decreasing cerebral blood volume (CBV). Using susceptibility contrast magnetic resonance imaging in thiopental-anesthetized rats, we found differences between brain regions in their transient CBV response to sustained hyperventilation.


Assuntos
Anestésicos Intravenosos/farmacologia , Volume Sanguíneo , Circulação Cerebrovascular , Hiperventilação/fisiopatologia , Tiopental/farmacologia , Anestesia , Animais , Meios de Contraste/farmacocinética , Feminino , Concentração de Íons de Hidrogênio , Ratos , Ratos Sprague-Dawley
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