Forced-Air Warming in Patients Undergoing Endovascular Procedures: Comparison between 2 Thermal Blanket Models.

BACKGROUND: The purpose of this study was to compare the efficiency between 2 thermal blanket models: the upper blanket and the underbody blanket in patient heating and hypothermia prevention during endovascular surgery. METHODS: Fifty patients, American Society of Anesthesiologists physical status 2-4, receiving endovascular surgery repair of infrarenal abdominal aortic aneurysm or lower limb angioplasty by endovascular technique were studied. Primary outcome was to determine which forced-air blanket is more warming effective during the surgeries. Age, type of surgery, gender, body mass index, surgery duration, and initial patient temperature were analyzed to determine possible hypothermia association as secondary outcomes. Patients were randomized and split into 2 groups based on blanket model. All patients received general anesthesia, and temperature was obtained by an esophageal thermometer inserted after tracheal intubation and registered at intervals of 15 min until extubation. RESULTS: Groups significantly differed in body temperature (P = 0.006) and hypothermia occurrence (P = 0.020). The underbody blanket group hada higher ratio of hypothermic patients and a lower average temperature at the end of surgery. The average temperature after 60 min in the underbody blanket group was lower than the upper blanket group,although this difference was only significant after 150 min (P = 0.020). CONCLUSIONS: We conclude that upper thermal blanket is more effective thanunderbody thermal blanket in patient warming and hypothermia prevention during endovascular abdominal aortic aneurysm repair and lower limb angioplasty after 150 min of anesthetic-surgical time duration.

Pulmonary function is better preserved in pigs when acute normovolemic hemodilution is achieved with hydroxyethyl starch versus lactated Ringer's solution.

Acute normovolemic hemodilution (ANH) has been proposed to decrease the need for allogenic blood transfusion. Consequently, great amounts of fluids are necessary to maintain hemodynamics during and after blood removal. The aim of this experiment was to evaluate the oxygenation, respiratory compliance, and lung structure during ANH performed with lactated Ringer's solution and hydroxyethyl starch (HES). Gas exchange, extravascular lung water, intrathoracic blood volume, serum osmolality, respiratory mechanics, and optical and electronic microscopy of lung biopsies were evaluated. Animals were randomized into three groups: CTL (control, n = 9), HES (HES 6% 200/0.5, n = 9), and LR (lactated Ringer's solution, n = 9). Animals in groups HES and LR underwent ANH to reach a preestablished hematocrit of around 15%. The removed blood was replaced with HES in a proportion of 1:1 and with lactated Ringer's solution 3:1. The LR group demonstrated a tendency for a marked time-dependence decrease in compliance (P = 0.013 in T2; P = 0.008 in T3) and in Pao2/fraction of inspired oxygen (Fio2) ratio (P = 0.033 in T2) as well as an increase in (A-a) Grad O2 (P = 0.037 in T2). Extravascular lung water and intrathoracic blood volume did not present any significant variation among the groups. In contrast, serum osmolality presented a significant decline in animals hemodiluted with lactated Ringer's solution. Optical and electronic microscopy of lungs biopsies revealed moderate to serious collapses and basement membrane enlargement in LR group. In this kind of experimental model, ANH with 6% HES (200/0.5) seems to preserve lung structure better as evidenced by maintenance of oxygenation indexes and respiratory compliance when compared with that in the Ringer's solution hemodiluted group.

Efeitos cardiovasculares das manobras de recrutamento alveolar durante lesão pulmonar aguda por ácido clorídrico: estudo experimental em suínos / Cardiovascular effects of alveolar recruitment maneuvres during acute lung injury by hydrocholoric acid experimental study in pigs

Os efeitos hemodinâmicos do aumento progressivo de PEEP e das manobras de recrutamento alveolar do tipo insuflação sustentada, com pressão máxima de 30 cmH2O, foram estudados em trinta e dois animais, por meio de ecocardiografia transesofágica, débito cardíaco por termodiluição, pressões sistêmicas e pulmonares, transporte de oxigênio e tonometria gástrica. A lesão pulmonar aguda foi realizada por instilação broncoalveolar de ácido clorídrico.Houve comprometimento hemodinâmico decorrente do incremento de PEEP, sem alterações cardiovasculares conseqüentes da insuflação sustentada ou da lesão pulmonar aguda, após 3 horas...

The hemodynamic effects of progressive PEEP incremental and sustained inflation alveolar recruitment maneuvers, with 30 cmH2O of airway peak pressure, were evaluated in thirty-two animals, by means of transesophageal echocardiography, cardiac output by thermodilution, systemic and pulmonary pressures, oxygen transportation and gastric tonometry. The acute lung injury was induced by bronchoalveolar instillation of hydrochloric acid. It was observed hemodynamic compromise due to PEEP incremental, however acute lung injury or sustained inflation did not cause deleterious cardiovascular effect after three hours...

Incidência de isquemia miocárdia no pós-operatório de pacientes submetidos à cirurgia para correçäo de aneurisma de aorta abdominal: estudo retrospectivo / Postoperative myocardial ischemia in patients undergoing abdominal aortic aneurysm repair: a retrospective study

Justificativa e Objetivos: Muitos pacientes submetidos à cirurgia para correçäo de aneurisma de aorta abdominal apresentam doença coronariana, podendo evoluir com complicaçöes cardíacas perioperatórias. A grande dificuldade é avaliar, no pré-operatório, o risco de complicaçöes cardíacas isquêmicas que ocorrem no período pós-operatório de modo confiável. O objetivo deste estudo foi verificar a incidência de isquemia cardíaca pós-operatória em pacientes submetidos à correçäo de aneurisma da aorta abdominal, sua correlaçäo com índice de risco cardíaco de Goldman modificado, com alteraçöes no teste do tálio-dipiridamol e os fatores de risco nessa populaçäo. Método: Foram analisados retrospectivamente 65 pacientes submetidos à correçäo de aneurisma da aorta abdominal e a incidência dos fatores de risco como tabagismo, insuficiência coronariana no pré-operatório, o índice de Goldman modificado e as complicaçöes isquêmicas pós-operatórias. Foi avaliada a correlaçäo do teste tálio-dipiridamol pré-operatório e eventos isquêmicos no pós-operatório. Resultados: Cerca de 80 por cento dos pacientes apresentavam antecedente de tabagismo, 55 por cento de hipertensäo arterial, 8 por cento de Diabetes mellitus, 25 por cento de insuficiência coronariana. Entre os pacientes com insuficiência coronariana, cinco possuíam angina pré-operatória e apresentaram uma incidência de 40 por cento de isquemia miocárdia no pós-operatório, sendo a incidência de infarto agudo do miocárdio de 6,2 por cento. No nosso estudo, 14 por cento dos pacientes Goldman modificado II e 33 por cento dos pacientes Goldman modificado III apresentaram isquemia miocárdica pós-operatória. Dezesseis pacientes (24 por cento) foram submetidos ao tálio dipiridamol no pré-operatório, sendo que 10 (62 por cento) apresentaram defeitos de captaçäo cintilográfica. O valor preditivo positivo do exame foi de 20 por cento para isquemia miocárdica pós-operatória, com valor preditivo negativo de 83 por cento e sensibilidade de 66 por cento