Efeitos da PEEP na ventilação controlada a volume sobre parâmetros hemodinâmicos em suínos submetidos ao pneumoperitônio associado ao cefalodeclive / Effects of PEEP on hemodynamic variables in pigs submitted to volume-controlled ventilation under pneumoperitoneum associated to cephalodeclive

Videolaparoscopic procedures have gained prominence due to their low invasiveness, causing less surgical trauma and better post-surgical recovery. However, the increase in intra-abdominal pressure due to the institution of pneumoperitoneum can alter the patient's homeostasis. Therefore, volume-controlled ventilation, associated with positive end-expiratory pressure (PEEP), improves arterial oxygenation and prevents pulmonary collapse, but it can lead to important hemodynamic changes. The aim of this study was to evaluate, comparatively, the effects of positive end expiratorypressure (PEEP) on hemodynamic variables of pigs submitted to volume-controlled ventilation, during pneumoperitoneum and maintained in head-down tilt and determine which PEEP value promotes greater stability on hemodynamic variables. Twenty-four pigs were used, between 55 and 65-day-old, weighing between 15 and 25 kg, randomly divided into 3 distinct groups differentiated by positive end-expiratory pressure: PEEP 0 (volume-controlled ventilation and PEEP of 0 cmH2O), PEEP 5 (volume-controlled ventilation and PEEP of 5 cmH2O) and PEEP 10 (volume-controlled ventilation and PEEP of 10 cmH2O). Volume-controlled ventilation was adjusted to 8 mL/kg of tidal volume and a respiratory rate of 25 movements per min. Anesthesia was maintained with continuous infusion of propofol (0.2 mg/kg/min) and midazolam (1 mg/kg/h). Pneumoperitoneum was performed with carbon dioxide (CO2), keeping the intraabdominal pressure at 15 mmHg and the animals were positioned on a 30° head-down tilt. The evaluations of hemodynamic variables started 30 min after induction of anesthesia (M0), followed by measurements at 15-min intervals (from M15 to M90), completing a total of 7 evaluations. The variables of interest were collected over 90 min and submitted to analysis of variance followed by Tukey's post-hoc test, with P < 0.05. The PEEP 10 group had higher values of CVP and mCPP, while the PEEP 5 group, mPAP and PVR were higher. The PEEP 0 group, on the other hand, had higher means of CI. Regarding the moments, there were differences in HR, SAP, DAP, MAP, CO, IC and TPR. According to the literature, important hemodynamic effects due to pneumoperitoneum are reported, which can be caused by the pressure used in abdominal insufflation, CO2 accumulation, duration of the surgical procedure, hydration status and patient positioning. Mechanical ventilation associated with PEEP can also cause an increase in intrathoracic pressure and, therefore, reduce cardiac output. Cardiovascular changes are proportional to the PEEP used. Central venous pressure (PVC) measure the patient's preload, and intrathoracic pressure can interfere with this parameter. The peak pressure values in the PEEP 10 group were higher than the other groups, demonstrating that the increase in intrathoracic pressure results in higher PVC values. Regarding PAPm and PCPm, these variables can be influenced according to the PEEP values and the patient's position. In relation to CI, the increase in PEEP may reflect on intrathoracic pressure, resulting in greater compression of the heart, with a consequent reduction in cardiac output and cardiac index. Therefore, it is concluded that the PEEP effects of 0 cmH2O and 5 cmH2O on hemodynamics are discrete, under the proposed conditions.(AU)

S100B level and cognitive dysfunction after robotic-assisted laparoscopic radical prostatectomy procedures: a prospective observational study / Nível de S100B e disfunção cognitiva após prostatectomia radical laparoscópica assistida por robô: estudo observacional prospectivo

Abstract Background: The present study investigated the association between Postoperative Cognitive Dysfunction (POCD) and increased serum S100B level after Robotic-Assisted Laparoscopic Radical Prostatectomy (RALRP). Methods: The study included 82 consecutive patients who underwent RALRP. Serum S100B levels were determined preoperatively, after anesthesia induction, and at 30 minutes and 24 hours postoperatively. Cognitive function was assessed using neuropsychological testing preoperatively, and at 7 days and 3 months postoperatively. Results: Twenty four patients (29%) exhibited POCD 7 days after surgery, and 9 (11%) at 3 months after surgery. Serum S100B levels were significantly increased at postoperative 30 minutes and 24 hours in patients displaying POCD at postoperative 7 days (p = 0.0001 for both) and 3 months (p = 0.001 for both) compared to patients without POCD. Duration of anesthesia was also significantly longer in patients with POCD at 7 days and 3 months after surgery compared with patients without POCD (p = 0.012, p = 0.001, respectively), as was duration of Trendelenburg (p = 0.025, p = 0.002, respectively). Composite Z score in tests performed on day 7 were significantly correlated with duration of Trendelenburg and duration of anesthesia (p = 0.0001 for both). Conclusions: S100B increases after RALRP and this increase is associated with POCD development. Duration of Trendelenburg position and anesthesia contribute to the development of POCD. Trial Registry Number: Clinicaltrials.gov (N° NCT03018522).

Resumo Introdução: O presente estudo investigou a associação entre Disfunção Cognitiva Pós-Operatória (DCPO) e aumento do nível sérico de S100B após Prostatectomia Radical Laparoscópica Assistida por Robô (PRLAR). Métodos: O estudo incluiu 82 pacientes consecutivos submetidos à PRLAR. Os níveis séricos de S100B foram determinados: no pré-operatório, após indução anestésica, e aos 30 minutos e 24 horas do pós-operatório. A função cognitiva foi avaliada com testes neuropsicológicos no pré-operatório, no 7° dia pós-operatório (7 DPO) e aos 3 meses após a cirurgia (3 MPO). Resultados: Observamos 24 pacientes (29%) com DCPO no 7 DPO e 9 pacientes com DCPO (11%) após 3 meses da cirurgia. Quando comparados com os pacientes sem DCPO, os níveis séricos de S100B estavam significantemente aumentados aos 30 minutos e às 24 horas do pós-operatório nos pacientes que apresentaram DCPO no 7 DPO (p= 0,0001 para os dois momentos) e 3 meses após a cirurgia (p= 0,001 para os dois momentos) A duração anestésica também foi significantemente maior em pacientes com DCPO no 7 DPO e 3 MPO em comparação com pacientes sem DCPO (p= 0,012, p= 0,001, respectivamente), assim como a duração da posição de Trendelenburg (p= 0,025, p= 0,002, respectivamente). O escore Z composto nos testes realizados no 7 DPO foi significantemente correlacionado com a duração da posição de Trendelenburg e a duração da anestesia (p= 0,0001 para ambos). Conclusão: S100B aumenta após PRLAR e o aumento está associado ao desenvolvimento de DCPO. A duração anestésica e o tempo decorrido em posição de Trendelenburg contribuem para o desenvolvimento de DCPO. Número de registro do estudo: Clinicaltrials.gov (n° NCT03018522)

Are Preexisting Retinal and Central Nervous System-Related Comorbidities Risk Factors for Complications Following Robotic-Assisted Laparoscopic Prostatectomy?

ABSTRACTPurpose:To assess whether retinal and central nervous system (CNS) comorbidities are risk factors for complications following robotic assisted laparoscopic prostatectomy (RALP).Materials and Methods:A retrospective review of our RALP database identified 1868 patients who underwent RALP by a single surgeon between December 10, 2003-March 14, 2014. We hypothesized that patients with preexisting retinal or CNS comorbidities were at a greater risk of suffering retinal and CNS complications following RALP. Perioperative complications and risk of recurrence were graded using the Clavien and D'Amico systems, respectively.Results:40 (2.1%) patients had retinal or CNS-related comorbidities, of which 15 had a history of retinal surgery and 24 had a history of cerebrovascular accident, aneurysm and/or neurosurgery. One additional patient had a history of both retinal and CNS events.Patients with retinal or CNS comorbidities were significantly older, had elevated PSA levels and CCI (Charlson Comorbidity Index) scores than the control group. Blood loss, length of stay, surgical duration, BMI, diagnostic Gleason score and T-stage were not statistically different between groups.No retinal or CNS complications occurred in either group. The distribution of patients between D'Amico risk categories was not statistically different between the groups. There was also no difference in the incidence of total complications between the groups.Conclusions:RALP-associated retinal and CNS complications are rare. While our RALP database is large, the cohort of patients with retinal or CNS-related comorbidities was relatively small. Our dataset suggests retinal and CNS pathology presents no greater risk of suffering from perioperative complications following RALP.