Differences of cerebral oxygen saturation in dialysis patients: a comparison of three principals of near infrared spectroscopy.

PURPOSE: It has been reported that cerebral oxygen saturation (rSO2) measured by near infrared spectroscopy is low in dialysis patients. We compared the rSO2 values of dialysis patients before living donor kidney transplantation and their donors as controls by using three spectroscopes that utilize different principals, the INVOS 5100C (spatially resolved spectroscopy), FORE-SIGHT ELITE (modified Beer-Lambert law) and tNIRS-1 (time-resolved spectroscopy). METHODS: Before induction of anesthesia, the sensors of one of the three spectroscopes were placed on the forehead and rSO2 values were recorded followed by the same measurement using the other two spectroscopes. The primary objective was to compare the rSO2 values of the dialysis patients and controls using the three spectroscopes by the unpaired t test. Then we compared the rSO2 values among the spectroscopes in both dialysis patients and controls by one-way ANOVA. Finally, we examined the relations between the rSO2 values and the physiological values by using the Pearson correlation coefficient. RESULTS: Fifteen pairs of dialysis patients and controls were studied. With the INVOS 5100 C, the values of the dialysis patients (59.7 ± 9.7% (mean ± standard deviation) were 13% lower than those of the controls (73.3 ± 6.9%) (P < 0.01). With the tNIRS-1, the values were 57.8 ± 4.8% in the dialysis patients and 63.3 ± 3.5% in the controls (P < 0.01). Almost no differences were observed with the FORE-SIGHT ELITE (71.6 ± 4.9% [dialysis patients] vs. 70.8 ± 4.3% [Controls]) (P = 0.62). Among the spectroscopes, the values were significantly different in both dialysis patients and controls. For the INVOS 5100C and tNIRS-1, correlation coefficients between rSO2 values and blood Hb and serum Alb were more than 0.5. CONCLUSIONS: The rSO2 values for comparisons between the dialysis patients and the controls were different according to differences of the principles of the near infrared spectroscopes. In the INVOS 5100C and tNIRS-1, rSO2 values may be related to blood Hb and serum Alb.

Intraoperative myocardial infarction and refractory cardiogenic shock during major hepatectomy: a case report.

BACKGROUND: Myocardial infarction (MI) complicated by cardiogenic shock during non-cardiac surgery is a rare but fatal complication. The management of intraoperative MI is challenging. CASE PRESENTATION: A 77-year-old hypertensive man with good functional capacity was scheduled for hepatectomy. After the start of liver resection, the electrocardiogram monitor showed ST depression, and the patient developed refractory cardiogenic shock. Transesophageal echocardiography revealed severe hypokinesis of the anteroseptal wall. The surgery was suspended, and an intra-aortic balloon pump was placed following immediate abdominal closure. Coronary angiography revealed severe stenosis of the left main coronary trunk, and percutaneous coronary intervention (PCI) was performed. Myocardial wall motion improved, and blood pressure stabilized. Two days after PCI, hepatectomy, which had been suspended, was successfully completed. CONCLUSIONS: Once intraoperative MI has occurred, early diagnosis and multidisciplinary approaches are important to manage the difficult clinical situation.

Altered microvascular reactivity assessed by near-infrared spectroscopy after hepato-pancreato-biliary surgery.

Little is known about microcirculatory dysfunction following abdominal surgeries. This study aimed to evaluate changes in microvascular reactivity (MVR) before and after major abdominal surgery, assessed by near-infrared spectroscopy in conjunction with a vascular occlusion test. This prospective observational study included 50 adult patients who underwent hepato-pancreato-biliary surgery lasting ≥ 8 h. MVR was assessed by tissue oxygen saturation (StO2) changes in the plantar region of the foot during 3 min of vascular occlusion and subsequent release under general anesthesia before and after surgery. The primary outcome was alteration in the recovery slope of StO2 (RecStO2) and recovery time (tM) between the preoperative and postoperative values. Postoperative short-term outcome was represented by the Post-operative Morbidity Survey (POMS) score on the morning of postoperative day 2. After surgery, RecStO2 was reduced (0.74% [0.58-1.06]/s vs. 0.89% [0.62-1.41]/s, P = 0.001), and tM was longer (57.0 [42.9-71.0] s vs. 41.3 [35.5-56.5] s, P < 0.001), compared to the preoperative values. Macrohemodynamic variables such as cardiac index, arterial pressure, and stroke volume during postoperative measurement did not differ with or without relative MVR decline. In addition, the POMS score was not associated with postoperative alterations in microcirculatory responsiveness. MVR in the plantar region of the foot was reduced after major hepato-pancreato-biliary surgery regardless of macrocirculatory adequacy. Impaired MVR was not associated with short-term outcomes as long as macrocirculatory indices were well maintained. The impact of relative microcirculatory changes, especially combined with inadequate macrocirculation, on postoperative complications remains to be elucidated.Clinical Trial Registrations UMIN-CTR trial ID: 000033461.

Diagnostic timing dependent characteristics of acute kidney injury following hepatectomy: a retrospective historical cohort analysis.

BACKGROUND: The timing of diagnosis of post-hepatectomy acute kidney injury (AKI) has rarely been investigated. The aim of this retrospective study was to reveal the differences between AKI subtypes following hepatectomy, as classified by timing of diagnosis. METHOD: Post-hepatectomy AKI was classified as very transient AKI (vtAKI; criteria satisfied by the serum creatinine value immediately after surgery) or non-transient AKI (ntAKI; all other AKI types except for vtAKI). Multivariate logistic regression analyses for both AKI types were performed separately to identify differences in known perioperative AKI risk factors. The impacts of each AKI subtype on postoperative complications, hospital stay and renal outcome at discharge were also evaluated. RESULTS: AKI was diagnosed in 135 of 750 patients (18.0%); 82 and 53 patients were classified as vtAKI and ntAKI, respectively. In multivariate analysis, even among the perioperative factors associated with whole AKI, there were distinct relationships depending on vtAKI or ntAKI. Furthermore, only ntAKI was associated with postoperative complications, longer hospital stays and impaired renal function at discharge. CONCLUSIONS: Based on the results of this study, future post-hepatectomy AKI studies should only include ntAKI and exclude vtAKI, as vtAKI has minimal clinical impact despite accounting for a significant proportion of AKI patients. CLINICAL TRIAL REGISTRATIONS: None.

Changes of Cerebral Oxygenation in Sequential Glenn and Fontan Procedures in the Same Children.

Recently, it is common to perform the Fontan procedure after the Glenn procedure as surgical repair for the univentricular heart. How the brain oxygen saturation (rSO2) values change with the cardiac restoration and the process of growth during these procedures in individual children remains unknown. In this study, we retrospectively studied rSO2 data as well as the perioperative clinical records of 30 children who underwent both Glenn and Fontan procedures by the same surgeon in the same institute. The rSO2 was measured at the beginning and end of each procedure with an INVOS 5100C. Cerebral perfusion pressure was calculated by subtracting central venous pressure from mean arterial pressure. Arterial oxygen saturation (SaO2) and the hemoglobin concentration were obtained as candidates affecting rSO2 changes at the start and the end of both procedures. The rSO2 increased during the Glenn procedure, but this increase was slight and insignificant. On the other hand, the rSO2 significantly increased during the Fontan procedure. Significant increases in SaO2 were observed only between the beginning and end of the Fontan procedure. Correlation coefficients determined by linear regression analysis were more than 0.5 between rSO2 and SaO2 in both procedures. Multiple linear regression analysis showed that SaO2 was the key determinant of the rSO2. The rSO2 increases step by step from the Glenn to the Fontan procedure in the same patient. Within each procedure, SaO2 is the key determinant of the rSO2. The significance of rSO2 monitoring in these procedures should be further evaluated.