Impact of hypotension and global hypoperfusion in postoperative delirium: a pilot study in older adults undergoing open colon surgery / Impacto da hipotensão e hipoperfusão global sobre o delírio pós-operatório: um estudo piloto com idosos submetidos à cirurgia aberta do cólon

Abstract Background: Post-operative delirium is a serious complication in patients undergoing major abdominal surgery. It remains unclear whether peri-operative hemodynamic and perfusion variables affect the risk for postoperative delirium. The objective of this pilot study was to evaluate the association between perfusion and hemodynamics peri-operative with the appearance of post-operative delirium. Methods: Prospective cohort study of adults 60 years or older undergoing elective open colon surgery. Multimodal hemodynamic and perfusion variables were monitored, including central venous oxygenation (ScvO2), lactate levels, and non-invasive cerebral oxygenation (rSO2), according to a standard anesthesia protocol. Fisher's exact test or Student's t-test were used to compare patients who developed post-operative delirium with those who did not (p < 0.05). Results: We studied 28 patients, age 73 ± 7 years, 60.7% female. Two patients developed post-operative delirium (7.1%). These two patients had fewer years of education than those without delirium (p = 0.031). None of the peri-operative blood pressure variables were associated with incidence of post-operative delirium. In terms of perfusion parameters, postoperative ScvO2 was lower in the delirium than the non-delirium group, without reaching statistical significance (65 ± 10% vs. 74 ± 5%; p = 0.08), but the delta-ScvO2 (the difference between means post-operative and intra-operative) was associated with post-operative delirium (p = 0.043). Post-operative lactate and rSO2 variables were not associated with delirium. Conclusions: Our pilot study suggests an association between delta ScvO2 and post-operative delirium, and a tendency to lower post-operative ScvO2 in patients who developed delirium. Further studies are necessary to elucidate this association.

Resumo Justificativa: O delírio pós-operatório é uma complicação séria em pacientes submetidos à cirurgia abdominal de grande porte. Ainda não está claro se as variáveis hemodinâmicas e de perfusão no período perioperatório afetam o risco de delírio pós-operatório. O objetivo deste estudo piloto foi avaliar a associação entre perfusão e hemodinâmica no perioperatório com o surgimento de delírio pós-operatório. Métodos: Estudo prospectivo de coorte de adultos com 60 anos ou mais, submetidos à cirurgia eletiva aberta do cólon. As variáveis multimodais de hemodinâmica e perfusão foram monitoradas, inclusive oxigenação venosa central (ScvO2), níveis de lactato e oxigenação cerebral não invasiva (rSO2), de acordo com um protocolo-padrão de anestesia. O teste exato de Fisher ou o teste t de Student foram usados para comparar os pacientes que desenvolveram delírio pós-operatório com aqueles que não desenvolveram p < 0,05. Resultados: Avaliamos 28 pacientes, 73 ± 7 anos, 60,7% do sexo feminino. Dois pacientes desenvolveram delírio pós-operatório (7,1%). Esses dois pacientes tinham menos anos de escolaridade do que aqueles sem delírio pós-operatório (p = 0,031). Nenhuma das variáveis de pressão arterial no perioperatório foi associada à incidência de delírio. Quanto aos parâmetros de perfusão, ScvO2 foi menor no grupo que apresentou delírio pós-operatório do que no grupo que não apresentou delírio, sem atingir significância estatística (65 ± 10% vs. 74 ± 5%; p = 0,08), mas o delta-ScvO2 (a diferença entre as médias no pós-operatório e intraoperatório) foi associado ao delírio (p = 0,043). As variáveis de lactato e rSO2 no pós-operatório não foram associadas ao delírio. Conclusões: Nosso estudo piloto sugere uma associação entre delta-ScvO2 e delírio e uma tendência à diminuição da ScvO2 no pós-operatório de pacientes com delírio. Estudos adicionais são necessários para elucidar essa associação.

[Impact of hypotension and global hypoperfusion in postoperative delirium: a pilot study in older adults undergoing open colon surgery]. / Impacto da hipotensão e hipoperfusão global sobre o delírio pós­operatório: um estudo piloto com idosos submetidos à cirurgia aberta do cólon.

BACKGROUND: Post-operative delirium is a serious complication in patients undergoing major abdominal surgery. It remains unclear whether peri-operative hemodynamic and perfusion variables affect the risk for postoperative delirium. The objective of this pilot study was to evaluate the association between perfusion and hemodynamics peri-operative with the appearance of post-operative delirium. METHODS: Prospective cohort study of adults 60 years or older undergoing elective open colon surgery. Multimodal hemodynamic and perfusion variables were monitored, including central venous oxygenation (ScvO2), lactate levels, and non-invasive cerebral oxygenation (rSO2), according to a standard anesthesia protocol. Fisher's exact test or Student's t-test were used to compare patients who developed post-operative delirium with those who did not (p<0.05). RESULTS: We studied 28 patients, age 73±7 years, 60.7% female. Two patients developed post-operative delirium (7.1%). These two patients had fewer years of education than those without delirium (p=0.031). None of the peri-operative blood pressure variables were associated with incidence of post-operative delirium. In terms of perfusion parameters, postoperative ScvO2 was lower in the delirium than the non-delirium group, without reaching statistical significance (65±10% vs. 74±5%; p=0.08), but the delta-ScvO2 (the difference between means post-operative and intra-operative) was associated with post-operative delirium (p=0.043). Post-operative lactate and rSO2 variables were not associated with delirium. CONCLUSIONS: Our pilot study suggests an association between delta ScvO2 and post-operative delirium, and a tendency to lower post-operative ScvO2 in patients who developed delirium. Further studies are necessary to elucidate this association.

[Early enteral nutrition in cancer patients subjected to a total gastrectomy]. / Nutrición enteral precoz en pacientes con gastrectomía total por cáncer.

BACKGROUND: Total parenteral nutrition has a high cost and frequency of complications. Enteral feeding is a feasible alternative that can be started early in the postoperative period. AIM: To assess digestive tolerance to early enteral feeding in cancer patients undergoing total gastrectomy and to compare early enteral feeding (EEF) with total parenteral nutrition plus enteral feeding (TPN + EF), initiated after overcoming postoperative ileus. PATIENTS AND METHODS: Subjects with a resectable gastric cancer were considered eligible for the study. During surgery a nasoenteral tube was placed and patients were prospectively randomized to EEF or TPN + EF. Digestive tolerance, effectiveness, complications and costs between both modalities of nutritional support were compared. RESULTS: Twenty eight patients (15 male, aged 63 +/- 14 years old) were studied. Fourteen patients were randomized to EEF and 14 to TPN + EF. Diarrhea occurred in 14 and 29% of EEF and TPN + EF patients respectively, (p: NS). Patients with TPN + EF received an average of 28 Cal/kg/day and 1.1 g/kg/day proteins. Patients with EEF received an average of 29 Cal/kg/day and 0.8 g/kg/day proteins. At the eighth postoperative day, serum albumin was 3.9 +/- 0.7 and 3.2 +/- 0.5 g/dl in EEF and TPN + EF patients respectively (p < 0.05), serum prealbumin was 16.9 +/- 5 and 12.3 +/- 4.3 mg/dl in EEF and TPN + EF patients respectively (p < 0.05) and nitrogen balance was +2.4 +/- 1.5 and -1.6 +/- 0.6 g/24 h in EEF and TPN + EF patients respectively (p < 0.05). Postoperative hyperglycemia was observed with a lower frequency and nutritional support costs and length of hospital stay were significantly lower in the EEF group. CONCLUSIONS: After total gastrectomy EEF is well tolerated, safe and effective, even during the early postoperative ileus. This therapeutic modality could be the first choice for nutritional support in these patients.