Taketomo Soga

The relationship between hyperlactatemia and microcirculation in the thenar eminence as measured using near-infrared spectroscopy in patients with sepsis

Objective Near-infrared spectroscopy (NIRS)-derived variables during a vascular occlusion test (VOT) have recently been used to evaluate peripheral circulatory insufficiency in patients with sepsis. We investigated the relationship between NIRS-derived variables and the lactate concentration during sepsis. Methods This was a prospective observational study. Forty-one patients with sepsis were divided into two groups according to their blood lactate concentration: a high lactate group (≥2.0 mmol/l; n=15) and a normal lactate group (<2.0 mmol/l; n=26). NIRS was used to evaluate the tissue oxygen index (TOI) at the thenar eminence before and after a VOT. VOT was performed by sphygmomanometer cuff inflation around upper arm for 3 min. The TOI value before VOT was defined as the TOI baseline, the TOI value immediately after VOT was defined as the minimum TOI and the TOI value after releasing the muscle from the VOT was defined as the TOI after VOT. The ΔTOI was defined as the difference between the TOI after VOT and minimum TOI. Results NIRS-derived variables had significant differences between the normal lactate group and the high lactate group with respect to the TOI baseline (median: 65% vs 55%, p=0.01), TOI after VOT (median: 65% vs 46%, p<0.001) and ΔTOI (median: 19% vs 6%, p<0.001). The lactate concentration was significantly correlated with the TOI after VOT (R=0.594, p<0.001), TOI baseline (R=0.513, p<0.001), ΔTOI (R=0.488, p=0.001) and minimum TOI (R=0.377, p=0.02). Conclusions We revealed a significant correlation between NIRS-derived variables and the lactate concentration during sepsis.

Changes of cerebral oxygen metabolism and hemodynamics during ECPR with hypothermia measured by near-infrared spectroscopy: a pilot study.

BACKGROUND The 2010 CPR Guidelines recommend that extracorporeal cardiopulmonary resuscitation (ECPR) using an emergency cardiopulmonary bypass (CPB) should be considered for patients with cardiac arrest. However, it is not yet clear whether this therapy can improve cerebral circulation and oxygenation in these patients. To clarify this issue, we evaluated changes of cerebral blood oxygenation (CBO) during ECPR using near-infrared spectroscopy (NIRS). METHODS We employed NIRS to measure CBO in the bilateral frontal lobe in patients transported to the emergency room (ER) after out-of-hospital cardiac arrest between November 2009 and June 2011. RESULTS Fifteen patients met the above criteria. The tissue oxygenation index (TOI) on arrival at the ER was 36.5 %. This increased to 67.8 % during ECPR (P < 0.001). The one patient whose TOI subsequently decreased had a favorable neurological outcome. CONCLUSION Increase of TOI during ECPR might reflect an improvement in cerebral blood flow, while decrease of TOI after ECPR might reflect oxygen utilization by the brain tissue as a result of neuronal cell survival. NIRS may be useful for monitoring cerebral hemodynamics and oxygen metabolism during CPR.

Detection of ROSC in Patients with Cardiac Arrest During Chest Compression Using NIRS: A Pilot Study

Return of spontaneous circulation (ROSC) during chest compression is generally detected by arterial pulse palpation and end-tidal CO2 monitoring; however, it is necessary to stop chest compression during pulse palpation, and to perform endotracheal intubation for monitoring end-tidal CO2. In the present study, we evaluated whether near-infrared spectroscopy (NIRS) allows the detection of ROSC during chest compression without interruption. We monitored cerebral blood oxygenation in 19 patients with cardiac arrest using NIRS (NIRO-200NX, Hamamatsu Photonics, Japan). On arrival at the emergency room, the attending physicians immediately assessed whether a patient was eligible for this study after conventional advanced life support (ALS) and employed NIRS to measure cerebral blood oxygenation (CBO) in the bilateral frontal lobe in patients. We found cerebral blood flow waveforms in synchrony with chest compressions in all patients. In addition, we observed abrupt increases of oxy-hemoglobin concentration and tissue oxygen index (TOI), which were associated with ROSC detected by pulse palpation. The present findings indicate that NIRS can be used to assess the quality of chest compression in patients with cardiac arrest as demonstrated by the detection of synchronous waveforms during cardiopulmonary resuscitation (CPR). NIRS appears to be applicable for detection of ROSC without interruption of chest compression and without endotracheal intubation.

Ulinastatin Alone Does Not Reduce Caspase 3-mediated Apoptosis in Protease-positive Aeromonas hydrophilia-induced Sepsis

BACKGROUND/PURPOSE To evaluate the effect of ulinastatin, a protease inhibitor, on survival and apoptosis in protease-positive Aeromonas hydrophilia (PPAH)-induced sepsis. METHODS Thirty mice were randomly allocated to receive intraperitoneal injection of either phosphate buffered saline (PBS) (control mice, n = 10) or PPAH (PPAH mice, n = 20). After 30 minutes, control mice received an additional intraperitoneal PBS injection, 10 PPAH mice received intraperitoneal PBS injection (non-treated PPAH mice), and the remaining 10 PPAH mice received an intraperitoneal injection of ulinastatin (ulinastatin-treated PPAH mice). RESULTS Survival at 24 hours was 100% in control mice, and 35% (p < 0.05) in PPAH mice; the survival rate in non-treated and ulinastatin-treated PPAH mice were 30% and 40% (p > 0.05), respectively. The thymus weight (mg) decreased significantly in PPAH mice (51.1 +/- 14.9) compared to control mice (69.7 +/- 14.4; p < 0.001); there was no difference between ulinastatin-treated (52 +/- 13.9; p > 0.05) and non-treated PPAH mice (50.4 +/- 16). The thymus gland cell count reduced significantly in PPAH mice (8.1 +/- 4.7 x 10(7)) compared to control mice (12.8 +/- 6.6 x 10(7); p < 0.01), and immunofluorescence analysis demonstrated that the reduced cells were mostly CD4+ CD8+, in contrast to the increase in CD4+ CD8- cells. There was no difference in cell count between ulinastatin-treated (8.7 +/- 4.9 x 10(7)) and non-treated PPAH mice (7.4 +/- 4.6 x 10(7); p > 0.05). Caspase 3-mediated apoptosis was not detectable in control mice in contrast to the pronounced manifestation in PPAH mice. CONCLUSION PPAH-induced sepsis has a high mortality that is related to lymphocyte apoptosis. Ulinastatin alone does not significantly reduce caspase 3-mediated lymphocyte apoptosis.