<p>The extension of laparoscopic procedures into the chest may induce specific pathophysiologic effects.</p><p>In pigs, we have demonstrated how devastating a combined thoraco-laparoscopic approach can be for gas exchange. Furthermore, the transmission of elevated pressure intra-cranially is a potential danger. The application of positive end-expiratory pressure (PEEP) was found to improve gas exchange and, more importantly, hypoxemia could be avoided. The application of PEEP did not increase intra-cranial pressure further; nor did it adversely affect cerebral circulation.</p><p>Even before the introduction of the laparoscopic technique, there was a substantial increase in the annual number of antireflux procedures. Therefore, the threefold increase of the incidence of antireflux surgery recorded during the past decade cannot solely be explained by the introduction of minimal access surgery. However, a clear shift in the preferred methodology took place. This change was not scientifically supported at the time of the transition and, surprisingly, it is still not supported today. In comparison with open surgery, patients do not seem to derive significant long-term benefits from having the antireflux procedure done laparoscopically. As was demonstrated, laparoscopy might even be an inferior approach in some patients. Nevertheless, it is reasonable to assume that laparoscopy can yield equally good results as open surgery despite our failure to confirm that in our studies. Determination of the effectiveness of minimal access surgery in the treatment of GORD is critical, before minimal access techniques become the standard for antireflux surgery in the community.</p>

The extension of laparoscopic procedures into the chest may induce specific pathophysiologic effects. In pigs, we have demonstrated how devastating a combined thoraco-laparoscopic approach can be for gas exchange. Furthermore, the transmission of elevated pressure intra-cranially is a potential danger. The application of positive end-expiratory pressure (PEEP) was found to improve gas exchange and, more importantly, hypoxemia could be avoided. The application of PEEP did not increase intra-cranial pressure further; nor did it adversely affect cerebral circulation. Even before the introduction of the laparoscopic technique, there was a substantial increase in the annual number of antireflux procedures. Therefore, the threefold increase of the incidence of antireflux surgery recorded during the past decade cannot solely be explained by the introduction of minimal access surgery. However, a clear shift in the preferred methodology took place. This change was not scientifically supported at the time of the transition and, surprisingly, it is still not supported today. In comparison with open surgery, patients do not seem to derive significant long-term benefits from having the antireflux procedure done laparoscopically. As was demonstrated, laparoscopy might even be an inferior approach in some patients. Nevertheless, it is reasonable to assume that laparoscopy can yield equally good results as open surgery despite our failure to confirm that in our studies. Determination of the effectiveness of minimal access surgery in the treatment of GORD is critical, before minimal access techniques become the standard for antireflux surgery in the community.

nÃo hà / A hemorragia subaracnÃidea (HSA) à a presenÃa de sangue no espaÃo subaracnÃideo, sendo capaz de aumentar a pressÃo intracraniana (PIC) a nÃveis que promovem alto grau de morbidade e mortalidade. Apresenta diferentes etiologias. Poucos estudos demonstram os efeitos da HSA sobre o trato gastrintestinal (TGI). Trabalhos cientÃficos prÃvios demonstraram alteraÃÃes na motilidade do TGI, especificamente sobre a complacÃncia gÃstrica (CG), em indivÃduos com hipertensÃo intracraniana (HIC), tornando-os impossibilitados de utilizar a via enteral, com consequente comprometimento da absorÃÃo de alimentos e medicamentos. O objetivo deste trabalho à avaliar os efeitos da HSA sobre a CG. Neste estudo foram utilizados ratos Wistar (300-350 g), sob os auspÃcios do COBEA (CEUA/UFC- Protocolo n 41/2013). A anestesia foi realizada com Ketamina/Xilasina (20-10 mg/Kg;ip). A hemorragia subaracnÃidea e secundariamente a hipertensÃo intracraniana foram obtidas por injeÃÃo intratecal de 0,2 ml de sangue autÃlogo no Grupo Teste (HSA) e lÃquor-sÃmile no Grupo Controle (Sham). Um grupo de animais foi submetido, anteriormente à induÃÃo, a tratamento cirÃrgico para estudo da participaÃÃo neural autonÃmica no controle da CG. No momento da induÃÃo da HIC/HSA os animais foram submetidos à canulaÃÃo do ventrÃculo cerebral para aferiÃÃo da PIC e da artÃria femoral para obtenÃÃo de dados hemodinÃmicos. ApÃs 72 h da induÃÃo, considerada como fase intermediÃria do processo inflamatÃrio da HIC os animais foram novamente anestesiados e submetidos à mensuraÃÃo da CG. Esta foi avaliada mediante sistema de reservatÃrio em âUâ acoplado a sistema de pletismografia (Ugo BasilleÂ). Simultaneamente foram mensuradas PIC, PA e FC. Os dados foram analisados por teste âtâ student, sendo considerados estatisticamente significativos com p < 0,05. Os resultados do modelo experimental utilizados no estudo de induÃÃo de hemorragia subaracnÃidea mostrou-se bom modelo de obtenÃÃo de hipertensÃo intracraniana crÃnica. A hipertensÃo intracraniana secundÃria à hemorragia subaracnÃidea, alÃm de produzir hipertensÃo e bradicardia diminuiu a complacÃncia gÃstrica nos ratos anestesiados; estando esta tanto mais diminuÃda quanto maior os nÃveis de pressÃo intracraniana. O prÃ-tratamento cirÃrgico com vagotomia subdiafragmÃtica nÃo modificou os valores da complacÃncia gÃstrica, enquanto que o prÃ-tratamento cirÃrgico com esplancnotomia e gangliectomia celÃaca preveniu a diminuiÃÃo da complacÃncia gÃstrica induzida por hipertensÃo intracraniana secundÃria à hemorragia subaracnÃidea. Palavras-Chave: complacÃncia gÃstrica; hemorragia subaracnÃidea; pressÃo intracraniana; rato. / In addition to increase in the intra cranial pressure, subarachnoid hemorrhage (SAH) is responsible for high morbidity grade and high mortality levels. Varied consequences are well documented, though little is known on the impact of SAH on the gastrointestinal tract (GIT). However, we have previously documented that intracranial hypertension reduces gastric compliance (GC), which may hamper enteric nutrition and efficiency of oral administered drugs in affected patients. We studied the effects of SAH on GC. After authorization by the COBEA(CEUA/UFC- Protocol n 41/2013), 130 male Wistar (300-350) rats were anesthetized (Ketamine/Xylazine (20-10 mg/Kg; ip) before being subjected to SAH or Sham protocol. Autologous blood was injected intra-theca, constituting the SAH protocol; while injection of a similar volume (0.2ml) of a lÃquor-sÃmile fluid formed the Sham-protocol. A brain ventricle was cannulated, to later verify increase in intra-cranial pressure (ICP) during GC experiments, while the femoral artery was utilized to measure simultaneous hemodynamic values: cardiac frequency (CF) and arterial pressure (AP). Another group of animals were operated upon to study the role of the autonomic nervous system in this phenomenon. After 72hs, the animals were anesthesized and submitted to GC measurement protocol; by pletysmography (Ugo BasilleÂ). Simultaneous values of ICP, CF and PA were recorded. Data was compared and analyzed by âtâ student test, with values p (where p < 0.05) considered statistically significant.