Abstract Background: Postoperative nausea and vomiting (PONV) are major complications after general anesthesia. Although various pathways are involved in triggering PONV, hypotension plays an important role. We hypothesized that intraoperative hypotension during general anesthesia might be responsible for the incidence of PONV. Methods: We retrospectively investigated patients who underwent thyroidectomy. The initial blood pressure measured before induction of anesthesia was used as the baseline value. The systolic blood pressure measured during the operation from the start to the end of anesthesia was extracted from anesthetic records. The time integral value when the measured systolic blood pressure fell below the baseline value was calculated as area under the curve (AUC) of s100%. Results: There were 247 eligible cases. Eighty-eight patients (35.6%) had PONV. There was no difference in patient background between the patients with or without PONV. Univariate analysis showed that the total intravenous anesthesia (TIVA) (p = 0.02), smoking history (p = 0.02), and AUC-s100% (p = 0.006) were significantly associated with PONV. Multiple logistic regression analysis revealed that TIVA (OR: 0.54, 95% CI: 0.29–0.99), smoking history (OR: 0.60, 95% CI: 0.37–0.96), and AUC-s100% (OR: 1.006, 95% CI: 1.0–1.01) were significantly associated with PONV. Conclusion: Intraoperative hypotension evaluated by AUC-s100% was related to PONV in thyroidectomy.

Abstract Background: Maximum decrease of blood pressure and number of minutes of hypotension were independently associated with umbilical arterial pH. However, the impact of hypotension considering the duration of it on umbilical arterial pH is unknown. Methods: Pregnant women aged ≥ 20 years who delivered a baby at full-term via a cesarean delivery under a single-shot spinal anesthesia between January 2017 and March 2019 were included. The main outcome was to predict umbilical arterial pH, based on the value of the time integral of hypotension. Patient demographics, patient comorbidities, and intraoperative data, including the total dose of ephedrine and phenylephrine by fetal delivery and cumulative duration of maternal hypotension, were evaluated. Maternal hypotension was reflected as a decrease in systolic arterial pressure and mean arterial pressure to < 80% of baseline values. The systolic arterial pressure and mean arterial pressure were independently included in a multiple regression analysis along with all other explanatory factors to predict the umbilical arterial pH. Results: Of the 416 eligible patients, 381 were enrolled. When including the systolic arterial pressure or mean arterial pressure in the model, emergency cases, the total dose of ephedrine, hypertensive disorders of pregnancy, and systolic arterial pressure or mean arterial pressure values were found to be significant predictive factors of umbilical arterial pH. Conclusion: Our results suggest that an elevated time integral of maternal hypotension may have anegative impact on umbilical arterial pH. Therefore, to minimize the riskof fetal acidosis, maternal hypotension should be prevented with the consideration of vasopressors selection.

Resumo Justificativa: O presente estudo teve como objetivo examinar os fatores associados à Lesão Renal Aguda (LRA) no pós-operatório, centrando-se na hipotensão e perda de sangue intraoperatórias. Método: Estudo de coorte retrospectivo de pacientes submetidos a cirurgia de pâncreas entre Janeiro de 2013 e Dezembro de 2018. O desfecho primário foi ocorrência de LRA em até 7 dias após a cirurgia e o secundário, o tempo de hospitalização. A análise multivariada foi usada para determinar os fatores explicativos associados à LRA; a interação entre o valor integrado da hipotensão e volume de perda de sangue foi avaliada. As diferenças no tempo de hospitalização foram comparadas pelo teste U de Mann-Whitney. Resultados: Dos 274 pacientes, 22 pacientes apresentaram LRA. A raiz cúbica da área sob a pressão arterial média intraoperatória < 65 mmHg (Odds Ratio = 1,21; Intervalo de Confiança de 95% 1,01-1,45; p = 0,038) e volume de perda sanguínea > 500 mL (Odds Ratio = 3,81; Intervalo de Confiança de 95% 1,51-9,58; p = 0,005) estavam independentemente associados à lesão renal aguda. A interação entre hipotensão arterial média e volume de perda sanguínea em relação à lesão renal aguda apontou o modelo como significante (p < 0,0001) com efeito de interação (p = 0,0003). A LRA não apresentou relação significante com o tempo de hospitalização (19 vs. 28 dias, p = 0,09). Conclusões: A área sob hipotensão arterial e o volume de perda sanguínea > 500 mL no intraoperatório apresentaram associação com LRA no pós-operatório. Entretanto, se a pressão arterial média se mantém, mesmo em pacientes com grande volume de perda sanguínea, o risco de desenvolver LRA no pós-operatório é comparável ao risco dos pacientes com pequeno volume de perda sanguínea.

Abstract Purpose: This study aimed to investigate factors associated with postoperative Acute Kidney Injury (AKI) focusing on intraoperative hypotension and blood loss volume. Methods: This was a retrospective cohort study of patients undergoing pancreas surgery between January 2013 and December 2018. The primary outcome was AKI within 7 days after surgery and the secondary outcome was the length of hospital stay. Multivariate analysis was used to determine explanatory factors associated with AKI; the interaction between the integrated value of hypotension and blood loss volume was evaluated. The differences in length of hospital stay were compared using the Mann-WhitneyU-test. Results: Of 274 patients, 22 patients had experienced AKI. The cube root of the area under intraoperative mean arterial pressure of < 65 mmHg (Odds Ratio = 1.21; 95% Confidence Interval 1.01-1.45; p = 0.038) and blood loss volume of > 500 mL (Odds Ratio = 3.81; 95% Confidence Interval 1.51-9.58; p = 0.005) were independently associated with acute kidney injury. The interaction between mean arterial hypotension and the blood loss volume in relation to acute kidney injury indicated that the model was significant (p < 0.0001) with an interaction effect (p = 0.0003). AKI was not significantly related with the length of hospital stay (19 vs. 28 days, p = 0.09). Conclusion: The area under intraoperative hypotension and blood loss volume of > 500 mL was associated with postoperative AKI. However, if the mean arterial pressure is maintained even in patients with large blood loss volume, the risk of developing postoperative AKI is comparable with that in patients with small blood loss volume.