Avaliação da dinâmica pressórica na junção esofagogástrica em pacientes com doença do refluxo gastroesofágico antes e após a fundoplicatura de Nissen

Abstract

BACKGROUND. Gastroesophageal reflux disease (GERD) has a global prevalence of 8-33%. The pathophysiological mechanism of GERD include dysfunction of the anti-reflux barrier at the oesophagogastric junction (EGJ), mainly due to low pressure in the LES and inability of the crural diaphragm (CD) in raising the pressure in the EGJ. As the Nissen fundoplication (NF) changes the pressure profile of the EGJ in order to re-establish functionality of the anti-reflux barrier, it is the object of this study. METHODOLOGTY: 14 patients were selected (8 men and 6 women, average age of 42.7 years; mean BMI of 27.8), with typical symptoms and acid exposure time >4% in 24-hour PHmetry. 13 patients had oesophageal tissue complications: 4 oesophagitis A, 5 oesophagitis B, 3 oesophagitis C and 1 patient with Barrett's. These were subjected to HRM. Baseline respiratory pressure parameters, swallowing parameters and pressure parameters were also assessed during inspiratory manoeuvre under increasing loads (Threshold Manoeuvre) were evaluated. The patients were then sent to NF. New manometric evaluation was performed between 3 to 6 months after surgery. We used the Wilcoxon test for comparison of pre- and post-fundoplication data, with p <0.05 determined by statistical significance. RESULTS: In the landmark evaluation, the Prmin had a significant increase (p=0.002), Prmed and the EGJ-CI in the postoperative period increased, however without statistical significance (p= 0.064 and p=0.06, respectively). During the swallowing phase the IRP had a statistically significant increase in the postoperative period (p= 0.001), the same occurring with the average PIB (p= 0.01). There was even a statistically significant increase in DL and a reduction in CFV (p= 0.017 and 0.043, respectively. The DCI did not have statistically significant variation (p=0.7). During the assessment of inspiration under load, the maximum respiratory pressure values were lower for all loads after surgery (PmaxTH12, p=0.004; PmaxTH24, p=0.004; PmaxTH36, p=0.01; PmaxTH48, p=0.01). CONCLUSION: The NF change the pressure profile of the EGJ, restoring basal tone to the distal oesophagus and improving its contractile pattern. The study also shows that there is an increase in residual pressure after the LES swallowing relaxation. A lower dynamic functionality of the sutured CD was also confirmed. What is optimised in the postoperative period is its static function of contributing to the global tone of EGJ.