Predictive role of regional thigh tissue oxygen saturation monitoring during cardiopulmonary bypass in lung injury after cardiac surgery.

Acute respiratory distress syndrome (ARDS) is a serious complication following cardiac surgery mainly associated with the use of cardiopulmonary bypass (CPB), which could increase the risk of mortality and morbidity. This study investigated the association of regional oxygen saturation (rSO2) during CPB with postoperative outcomes, including respiratory function. Patients who underwent cardiac surgery with CPB from 2015 to 2019 were included. Near-infrared spectroscopy was used to monitor rSO2 at the forehead, abdomen, and thighs throughout the surgery. Postoperative markers associated with CPB were assessed for correlations with PaO2/FiO2 (P/F) ratios at intensive care unit (ICU) admission. Postoperative lung injury (LI) was defined as moderate or severe ARDS based on the Berlin criteria, and its incidence was 29.9% (20/67). On multiple regression analysis, the following were associated with P/F ratios at ICU admission: vasoactive-inotropic scores at CPB induction (P = 0.03), thigh rSO2 values during CPB (P = 0.04), and body surface area (P < 0.001). A thigh rSO2 of 71% during CPB was significantly predictive of postoperative LI with an area under the curve of 0.71 (P = 0.03), sensitivity of 0.70, and specificity of 0.68. Patients with postoperative LI had longer ventilation time and ICU stays. Thigh rSO2 values during CPB were a potential predictor of postoperative pulmonary outcomes.

Acute Kidney Injury after High-Flow Regional Cerebral Perfusion in Neonatal and Infant Aortic Arch Repair.

OBJECTIVES: We applied high-flow regional cerebral perfusion (HFRCP) for aortic arch reconstruction in neonates and infants by monitoring regional oxygen saturation of the thigh (rSO2T) using near-infrared spectroscopy to maintain peripheral perfusion. This study was designed to investigate the optimal perfusion flow of HFRCP for renal protection. METHODS: From 2009 to 2021, 28 consecutive neonates and infants who underwent aortic arch reconstruction with HFRCP were enrolled. The median age of the patients was 27 days; the median body weight was 3.0 kg. In HFRCP, perfusion flow was targeted at approximately 80-100 mL/kg/min and then lowered corresponding to brain rSO2 levels and blood gas data. Isosorbide dinitrate and chlorpromazine were administered to enhance peripheral perfusion flow. Regional oxygen saturation of the forehead and thighs were monitored. The stage of acute kidney injury (AKI) was classified based on the Kidney Disease Improving Global Outcomes criteria. RESULTS: No patients had neurological events and peritoneal dialysis after surgery. The incidence of AKI was 39.3% with only three patients having greater than stage 2 AKI. The maximum postoperative serum creatinine concentration was negatively associated with the lowest rSO2T during HFRCP. The rSO2T during HFRCP was a predictive factor for postoperative creatinine increase of ≧0.3 mg/dL. The area under receiver operating characteristic curve was 0.78 with the cutoff value of 48% for rSO2T. CONCLUSIONS: The rSO2T during HFRCP is a potential predictor of postoperative renal function. To prevent AKI, the rSO2T should be preserved more than 48% by increasing HFRCP flow.

Monitoring of intraoperative femoral oxygenation predicts acute kidney injury after pediatric cardiac surgery.

Cardiopulmonary bypass-associated acute kidney injury (CPB-AKI) is a pediatric cardiac surgery postoperative complication that is associated with a longer duration of mechanical ventilation and length of hospital stay. Identifying an early predictor of CPB-AKI is critical. Near infrared spectroscopy (NIRS), which can provide real-time monitoring of regional tissue oxygen saturation (rSO2) during CPB, may predict CPB-AKI in an early phase of surgical treatment. This study analyzed clinical data from 87 children who underwent an elective surgical repair of ventricular septal defect (VSD) from January 2013 to March 2019. NIRS sensors were placed on the patients' forehead, abdomen, and thighs. The pediatric modified risk, injury, failure, loss, and end-stage (p-RIFLE) score was determined for each patient postoperatively. The incidence of AKI based on the p-RIFLE classification was 11.5% at the end of surgery, 23.0% at 24 h after surgery, and 5.7% at 48 h after surgery. The AKI incidence rate was highest at 24 h after surgery. Multiple regression analysis revealed that femoral oxygenation (rSO2) during CPB, CPB time, oxygen delivery index (DO2i), and lactate at the end of CPB were independent risk factors for AKI. Receiver-operating characteristic curve analysis indicated that femoral oxygenation of 74% or less predicted AKI development within 24 h after surgery. In conclusion, rSO2 measured at the thigh during CPB is highly predictive of CPB-AKI.

Near-infrared spectroscopy device selection affects intervention management for cerebral desaturation during cardiopulmonary bypass surgery.

OBJECTIVE: Currently, several near-infrared spectroscopy oximetry devices are used for detecting cerebral ischemia during cardiopulmonary bypass (CPB) surgery. We investigated whether two different models of near-infrared spectroscopy oximetry devices affect the assessment of cerebral ischemia and its management during CPB. METHODS: From January 2017 to August 2017, 70 adult cardiovascular surgery cases were randomly assigned to 1 of 2 different near-infrared spectroscopy oximetry devices. The devices were INVOS 5100C (Medtronic, Minneapolis, MN, USA) (group I; n = 35) and FORE-SIGHT ELITE (CAS Medical Systems, Branford, CT, USA) (group F; n = 35). RESULTS: There were no significant differences in patient characteristics. The rSO2 values were significantly higher for patients in group F than for patients in group I. Scalp-Cortex distance showed negative correlations with the mean rSO2 values in group I (P = 0.01). Interventions for low rSO2 during CPB for groups I and F were increase perfusion flow (13:5; P = 0.03), blood transfusion (7:1; P = 0.02), and both (6:1; P = 0.04), respectively. The Scalp-Cortex distance in group I was significantly longer in patients who required intervention than in patients who did not (17.1 ± 2.5 vs 15.1 ± 1.6 mm; P = 0.007). CONCLUSIONS: It is inappropriate to use the same intervention criteria for different near-infrared spectroscopy oximetry devices. Moreover, brain atrophy influence rSO2 values depending on device selection. It is important to note that inappropriate device selection may misguide perfusionists into performing unnecessary or excessive intervention during CPB.

Regional thigh tissue oxygen saturation during cardiopulmonary bypass predicts acute kidney injury after cardiac surgery.

Cardiopulmonary bypass-associated acute kidney injury may appear postoperatively, but predictive factors are unclear. We investigated the potential of regional tissue oxygen saturation as a predictor of cardiopulmonary bypass-associated acute kidney injury. We analyzed the clinical data of 150 adult patients not on dialysis who underwent elective cardiac surgical procedures during January 2015-March 2017. Near-infrared spectroscopy was used to measure regional oxygen saturation. Sensors were placed on the patients' forehead, abdomen, and thigh. The incidence of acute kidney injury was 2% at the end of surgery, 13% at 24 h, and 9% at 48 h, with the highest at 24 h after surgery. The multiple regression analysis revealed that the thigh regional oximetry during cardiopulmonary bypass, oxygen delivery index, and neutrophil count at the end of cardiopulmonary bypass and surgery were independent risk factors for acute kidney injury. The receiver-operating characteristic curve analysis suggested that a cutoff of regional oxygen saturation at the thigh of ≤ 67% was predictive of acute kidney injury within 24 h after surgery. In conclusion, the regional oxygen saturation at the thigh during cardiopulmonary bypass is a crucial marker to predict postoperative acute kidney injury in adults undergoing cardiac surgery.

Markers of peripheral perfusion during high-flow regional cerebral perfusion for aortic arch repair.

OBJECTIVES: High-flow regional cerebral perfusion (HFRCP) provides cerebral and somatic oxygen delivery through collateral vessels during aortic arch repair in small children; however, optimal flow conditions during HFRCP have not been established. We sought to identify markers of peripheral perfusion during HFRCP. METHODS: Between 2009 and 2016, in total 20 consecutive pediatric patients undergoing aortic arch repair with HFRCP were enrolled in this prospective, observational study. Median age was 20 days (range, 6-116 days); median body weight was 2.77 kg (range, 1.8-4.98 kg). Oxygen delivery ratio (Do2R) was calculated as the oxygen delivery during HFRCP divided by the oxygen delivery before HFRCP. Regional oxygen saturations on the forehead and on the thigh (rSo2T) were monitored during HFRCP, and postoperative creatinine kinase and lactate concentrations were measured as postoperative outcomes. Multivariate analyses were performed to clarify the effectiveness of Do2R and rSo2T as markers of peripheral perfusion during HFRCP. RESULTS: No deaths or neurologic impairments occurred. Multivariate analysis showed that the lowest rSo2T (P = .005) and cardiopulmonary bypass time (P = .012) predicted postoperative creatinine kinase concentration. Do2R was the only factor to predict postoperative lactate concentration (P < .001). Receiver operating characteristic analysis showed that Do2R less than 0.66 predicted risk of high postoperative lactate concentration (>5.0 mmol/L), with area under the curve of 0.95. CONCLUSIONS: For aortic arch repair in small children, rSo2T and Do2R during HFRCP are useful markers for predicting peripheral perfusion. Maintaining higher Do2R during HFRCP minimizes postoperative increases in lactate and creatinine kinase concentrations.

Correction to: Cerebral oximetry for cardiac surgery: a preoperative comparison of device characteristics and pitfalls in interpretation.

In the original publication, the length unit of the SCD in Table 1 and Fig. 2 has been incorrectly published as cm. The correct length unit is mm.

Cerebral oximetry for cardiac surgery: a preoperative comparison of device characteristics and pitfalls in interpretation.

Regional cerebral oximetry using near-infrared spectroscopy devices is commonly used for detecting cerebral ischemia during cardiopulmonary bypass, and aim to avoid poor cerebral perfusion which may result in perioperative neurological impairment. Today, several devices that can detect cerebral ischemia are commercially available. Although these devices operate on the same measurement principles, their algorithms for detecting and calculating cerebral ischemia are different and no criteria for directly comparing values measured by such different devices exist. From January 2017 to August 2017, 80 adult cardiovascular surgery patients were enrolled in the prospective study. In each patient, preoperative regional cerebral oxygen saturation values were measured by two different devices and their correlations with various preoperative factors were evaluated. Regional cerebral oxygen saturation levels were significantly higher for values of FORE-SIGHT ELITE (CAS Medical Systems, Branford, CT, USA) (F value) than those of the INVOS 5100C (Medtronic, Minneapolis, MN, USA) (I value). Scalp-cortex distance, hemoglobin concentration, and the presence or absence of hemodialysis showed significant correlations with ratios of measured values specific to each device (F/I). An appropriate device should be selected according to preoperative patient characteristics, and factors influencing regional cerebral oxygen saturation values should be considered to ensure the correct interpretation of measured values. This research was conducted with the approval of the ethics committee of our university (approval number: B16-96).

Factors associated with a low initial cerebral oxygen saturation value in patients undergoing cardiac surgery.

Regional cerebral oximetry using near-infrared spectroscopy device, an INVOS 5100 C (Medtronic, Minneapolis, MN, USA), during cardiac surgery aims to avoid perioperative neurological impairment, especially during cardiopulmonary bypass. However, it is not uncommon to encounter critically low initial cerebral regional oxygen saturation or a low value unresponsive to intervention. Therefore, it is important to identify factors associated with low saturation value other than true cerebral hypoxia. We investigated the relationship between preoperative regional cerebral oxygen saturation and clinical variables during cardiac surgery. From January 2013 to May 2016, 462 patients underwent elective cardiac surgery. Patient's ≤12 years of age, with acute cerebral infarction, with previous intracranial hemorrhage or neurosurgery, with concomitant aortic surgery, and having off-pump coronary artery bypass surgery were excluded. The remaining 223 patients were monitored by intraoperative regional cerebral oximetry. Univariate analysis found that scalp-cortex distance, cerebrospinal fluid thickness, left ventricular ejection fraction, hemoglobin concentration, estimated glomerular filtration rate, and hemodialysis were significantly correlated with the initial regional oxygen saturation value. Multiple regression analysis revealed that scalp-cortex distance, left ventricular ejection fraction, hemoglobin, and hemodialysis remained as significant variables. A receiver operating characteristic analysis found that for a low initial regional oxygen saturation value of 40%, the thresholds of scalp-cortex distance, left ventricular ejection fraction, and hemoglobin concentration were 17.6 mm, 45.2%, and 7.5 g/dl, respectively. In conclusion, brain atrophy, poor left ventricular function, anemia, and hemodialysis were associated with low initial cerebral regional oxygen saturation values in adult cardiac surgery patients.

Effect of additional preoperative administration of the neutrophil elastase inhibitor sivelestat on perioperative inflammatory response after pediatric heart surgery with cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) elicits a systemic inflammatory response. Our previous reports revealed that prophylactic sivelestat administration at CPB initiation suppresses the postoperative acute inflammatory response due to CPB in pediatric cardiac surgery. The purpose of this study was to compare the effects of sivelestat administration before CPB and at CPB initiation in patients undergoing pediatric open-heart surgery. Twenty consecutive patients weighing 5-10 kg and undergoing ventricular septal defect closure with CPB were divided into pre-CPB (n = 10) and control (n = 10) groups. Patients in the pre-CPB group received a 24 h continuous intravenous infusion of 0.2 mg/kg/h sivelestat starting at the induction of anesthesia and an additional 0.1 mg/100 mL during CPB priming. Patients in the control group received a 24-h continuous intravenous infusion of 0.2 mg/kg/h sivelestat starting at the commencement of CPB. Blood samples were tested. Clinical variables including blood loss, water balance, systemic vascular resistance index, and the ratio between partial pressure of oxygen and fraction of inspired oxygen (P/F ratio) were assessed. White blood cell count and neutrophil count as well as C-reactive protein levels were significantly lower in the pre-CPB group according to repeated two-way analysis of variance, whereas platelet count was significantly higher. During CPB, mixed venous oxygen saturation remained significantly higher and lactate levels lower in the pre-CPB group. Postoperative alanine aminotransferase and blood urea nitrogen levels were significantly lower in the pre-CPB group than in the control group. The P/F ratio was significantly higher in the pre-CPB group than in the control group. Fluid load requirement was significantly lower in the pre-CPB group.Administration of sivelestat before CPB initiation is more effective than administration at initiation for the suppression of inflammatory responses due to CPB in pediatric open-heart surgery, with this effect being confirmed by clinical evidence.

Electromagnetic interference of implantable cardiac devices from a shoulder massage machine.

Shoulder massage machines have two pads that are driven by solenoid coils to perform a per cussive massage on the shoulders. There have been concerns that such machines might create electromagnetic interference (EMI) in implantable cardiac devices because of the time-varying magnetic fields produced by the alternating current in the solenoid coils. The objective of this study was to investigate the potential EMI from one such shoulder massage machine on implantable cardiac devices. We measured the distribution profile of the magnetic field intensity around the massage machine. Furthermore, we performed an inhibition test and an asynchronous test on an implantable cardiac pacemaker using the standardized Irnich human body model. We examined the events on an implantable cardioverter-defibrillator (ICD) using a pacemaker programmer while the massage machine was in operation. The magnetic field distribution profile exhibited a peak intensity of 212 (A/m) in one of the solenoid coils. The maximal interference distance between the massage machine and the implantable cardiac pacemaker was 28 cm. Ventricular fibrillation was induced when the massage machine was brought near the electrode of the ICD and touched the Irnich human body model. It is necessary to provide a "don't use" warning on the box or the exterior of the massage machines or in the user manuals and to caution patients with implanted pacemakers about the dangers and appropriate usage of massage machines.

Effect of the neutrophil elastase inhibitor sivelestat on perioperative inflammatory response after pediatric heart surgery with cardiopulmonary bypass: a prospective randomized study.

Cardiopulmonary bypass (CPB) elicits a systemic inflammatory response. The neutrophil elastase inhibitor sivelestat is known to suppress this systemic inflammatory response, which can eventually result in acute organ failure. The prophylactic effect of sivelestat on acute lung injury, especially in pediatric cardiac surgery, remains unclear. This prospective double-blind, randomized study evaluated the perioperative prophylactic effect of sivelestat in patients undergoing elective pediatric open heart surgery with CPB. Thirty consecutive patients, weighing 5-10 kg and undergoing open heart surgery with CPB, were assigned to sivelestat (n = 15) or control (n = 15) groups. From CPB initiation to 24 h after surgery, patients in the sivelestat group received a continuous intravenous infusion of 0.2 mg/kg/h sivelestat, whereas patients in the control group received the same volume of 0.9% saline. Blood samples were collected, and levels of interleukin (IL)-6, IL-8, tumor necrosis factor alpha, polymorphonuclear elastase (PMN-E), C-reactive protein (CRP), as well as the white blood cell (WBC) count, platelet count, and neutrophil count (NC) were measured. PMN-E levels, IL-8 levels, WBC count, NC, and CRP levels were significantly lower, and platelet count was significantly higher in the sivelestat group, according to repeated two-way analysis of variance. The activated coagulation time was significantly shorter in the sivelestat group, similarly, blood loss was significantly less in the sivelestat group. In conclusion, Sivelestat attenuates perioperative inflammatory response and clinical outcomes in patients undergoing pediatric heart surgery with CPB.

The effectiveness of high-flow regional cerebral perfusion in Norwood stage I palliation.

OBJECTIVE: Regional cerebral perfusion (RCP) has been shown to provide cerebral circulatory support during Norwood procedure. In our institution, high-flow RCP (HFRCP) from the right innominate artery has been induced to keep sufficient cerebral and somatic oxygen delivery via collateral vessels. We studied the effectiveness of HFRCP to regional cerebral and somatic tissue oxygenation in Norwood stage I palliation. METHODS: Seventeen patients, who underwent the Norwood procedure, were separated into two groups: group C (n=6) using low-flow RCP and group H (n=11) using HFRCP (mean flow: 54 vs 92mlkg(-1)min(-1), P<0.0001). The mean duration of RCP was 64±10min (range, 49-86min) under the moderate hypothermia. Chlorpromazine (3.0mgkg(-1)) was given to group H patients before and during RCP to increase RCP flow. The mean radial arterial pressure was kept <50mmHg during RCP. To clarify the effectiveness of HFRCP for cerebral and somatic tissue oxygenation, cerebral regional oxygen saturation (rSO(2)) and systemic venous oxygenation (SvO(2)) during RCP were compared between the two groups. Changes in the lactate level before and after RCP, and changes in the blood urea nitrogen (BUN), creatinine, lactate dehydrogenase (LDH), and creatinine kinase (CK) levels before and after surgery, were also compared between the groups. RESULTS: Mean rSO(2) was 82.9±9.0% in group H and 65.9±10.7% in group C (P<0.05). Mean SvO(2) during RCP was 98.2±4.3% in group H and 85.4±9.7% in group C (P<0.01). During RCP, lactate concentration significantly increased in group C compared with that in group H (P<0.001). After surgery, the LDH and CK levels significantly increased in group C compared with that in group H (P<0.05). CONCLUSIONS: Our study revealed that HFRCP preserved sufficient cerebral and somatic tissue oxygenation during the Norwood procedure. The reduction of vascular resistance of collateral vessels increased both cerebral and somatic blood flow, resulting in improved tissue oxygen delivery.

Miniaturized biocompatible cardiopulmonary bypass for the Fontan procedure.

PURPOSE: Postoperative inflammatory response and perioperative systemic edema are the risks of failed Fontan circulation. We evaluated the efficiency of the miniaturized, poly-2-methoxyethylacrylate (PMEA)-coated cardiopulmonary bypass (CPB) circuit, which we devised in 2003, in the Fontan circulation. METHODS: Thirty-seven patients who underwent the Fontan procedure between March 1996 and December 2006 were divided into two groups: one consisting of patients with a priming-volume >250 m on uncoated conventional bypass (group C; n = 20), and one consisting of those with miniaturized (<200 ml) and PMEA-coated circuits (group M; n = 17). We compared the body weight gain (%BWG), minimum platelet count, maximum postoperative C-reactive protein (CRP), and minimum hematocrit (Hct) levels during the operation, maximum white blood cell (WBC) count, and postoperative pleural effusion, between the two groups. Stepwise multiple logistic regression analyses were used to investigate the most affecting factors. RESULTS: The %BWG and CRP levels were significantly lower in group M (P = 0.047 and P = 0.012, respectively). The minimum platelet count was significantly higher in group M (P = 0.012). There were no significant differences in postoperative pleural effusion, minimum Hct, or maximum WBC. CONCLUSION: The miniaturized biocompatible CPB system reduced perioperative inflammatory responses.

Regional high-flow cerebral perfusion improves both cerebral and somatic tissue oxygenation in aortic arch repair.

BACKGROUND: Regional cerebral perfusion provides cerebral circulatory support during aortic arch reconstruction. We report the effectiveness of high-flow regional cerebral perfusion (HFRCP) from the right innominate artery to maintain sufficient cerebral and somatic oxygen delivery through collateral vessels. METHODS: Frontal cerebral and thoracolumbar probes to measure somatic regional oxygen saturation (rSo(2)) were used to continuously measure oxygenation during cardiopulmonary bypass in 18 patients (weight, 2.1 to 4.3 kg) who underwent arch reconstruction using HFRCP (mean flow, 82; range, 43 to 108 ml/kg/min). Procedures included 9 Norwood procedures, 5 coarctation of aorta/interruption of aorta complex repairs, and 4 aortic arch repairs for a single ventricle. Mean HFRCP duration was 51 + or - 17 minutes under moderate hypothermia. Mean radial arterial pressure was kept at less than 50 mm Hg during HFRCP, and chlorpromazine (mean dose, 2.8 mg/kg) was given to all patients before and during HFRCP to increase regional cerebral perfusion flow. Plasma lactate concentration was measured before and after HFRCP. RESULTS: During HFRCP, mean cerebral rSo(2) was 78.8% + or - 9.5%, somatic rSo(2) was 65.4% + or - 12.1%, and lactate concentration increased from 3.8 + or - 2.2 to 5.5 + or - 2.1 mmol/L. There was significant correlation between regional cerebral perfusion flow and somatic rSo(2). Significant inverse correlations were noted between regional cerebral perfusion flow and the increase of lactate concentration and between somatic rSo(2) and the increase of lactate concentration. CONCLUSIONS: High-flow regional cerebral perfusion preserved sufficient cerebral and somatic tissue oxygenation during aortic arch repair. The reduction of vascular resistance of collateral vessels increased both cerebral and somatic blood flow, resulting in improved tissue oxygen delivery.

The effectiveness of prestorage leukocyte-reduced red blood cell transfusion on perioperative inflammatory response with a miniaturized biocompatible bypass system.

OBJECTIVE: Since 2007, the Japanese Red Cross Blood Center has provided prestorage leukocyte-reduced red blood cell concentrates in which the leukocytes were reduced soon after collection. We have established a miniaturized bypass system (140 mL) to reduce the perioperative inflammatory responses. This study was designed to reveal the effectiveness of leukocyte-reduced red blood cell concentrate transfusion on perioperative inflammatory responses in pediatric cardiac surgery. METHODS: Between May 2006 and June 2008, 50 consecutive patients weighing less than 5 kg who underwent a surgical procedure with red blood cell concentrate transfusion using a miniaturized bypass system were reviewed retrospectively. Twenty-five patients before 2007 received stored red blood cell concentrate in which leukocytes were reduced with a filter just before transfusion (group A). After 2007, 25 patients received the prestorage leukocyte-reduced red blood cell concentrate transfusion (group B). The postoperative peak C-reactive protein level, peak white blood cell count, peak neutrophil count, percentage body weight gain, inotrope score, plasma lactate concentration, postoperative mechanical ventilation time, and length of intensive care unit stay were compared as the perioperative inflammatory response and morbidity for both groups. RESULTS: There were no significant differences in peak white blood cell count, peak neutrophil count, percentage body weight gain, and inotrope score between the groups. The peak C-reactive protein level in group A was significantly greater than that in group B (6.7 +/- 4.7 vs 4.2 +/- 3.6 mg/dL, P < .05). The lactate concentration at 12 and 24 hours after surgical intervention in group A was significantly greater than that in group B (3.1 +/- 2.5 vs 1.9 +/- 1.1 mmol/L [P < .05] and 2.2 +/- 0.2 vs 1.4 +/- 0.2 mmol/L [P < .05], respectively). The postoperative mechanical ventilation time and intensive care unit stay in group A were significantly greater than those in group B (5.9 +/- 7.4 vs 2.1 +/- 2.0 days [P < .05] and 9.8 +/- 7.9 vs 5.0 +/- 2.1 days [P < 0.05], respectively). Multivariate analyses showed that the leukocyte-reduced red blood cell concentrate transfusion reduced the peak C-reactive protein level (in milligrams per deciliter; coefficient, -2.95; 95% confidence interval [CI], -4.66 to -0.93; P = .003), postoperative mechanical ventilation time (in days; coefficient, -3.41; 95% CI, -6.07 to -0.74; P = .013), and intensive care unit stay (in days; coefficient, -4.51; 95% CI, -7.37 to -1.64; P = .003). CONCLUSIONS: Our study revealed that in neonates and small infants, compared with transfusions with stored red blood cell concentrate, transfusion of leukocyte-reduced red blood cell concentrates was associated with reduced perioperative inflammatory responses and improved clinical outcomes.

The influences of red blood cell transfusion on perioperative inflammatory responses using a miniaturized biocompatible bypass with an asanguineous prime.

Whole blood transfusion generates an inflammatory response and may contribute to organ dysfunction following cardiopulmonary bypass. We established a miniaturized (minimum 140 mL) and biocompatible bypass system to reduce perioperative inflammatory responses and avoid blood transfusions. This study was designed to reveal the influences of stored red blood cell (RBC) transfusions on perioperative inflammatory responses in infants. Fifty-four consecutive patients weighing 4-10 kg who underwent surgical procedures for complex heart anomalies with asanguineous prime were retrospectively reviewed. Twenty-two patients (40.7%) received RBC transfusions during CPB. The postoperative peak white blood cell count (p-WBC), peak neutrophil count (p-NC), and peak C-reactive protein (p-CRP) were compared for both patient groups. Stepwise multiple logistic regression analyses were used to investigate which of the factors most affected the perioperative inflammatory responses. The p-CRP and p-NC in patients with transfusion was significantly greater than those in patients without transfusion (CRP 8.1 +/- 5.1 versus 5.5 +/- 3.0 mg/dL, P < 0.05, p-NC 14.6 +/- 4.5 versus 12.0 +/- 4.0 x 1000/mm3, P < 0.05). Multivariate analyses showed that RBC transfusion most affected p-WBC (coefficient: 3.89, 95% confidence interval [CI] 0.79-6.99, P = 0.015) and p-NC (coefficient: 3.64, 95% CI 0.87-6.40, P = 0.011). The RBC transfusions increased the perioperative inflammatory responses, compared to transfusion-free procedures, even when using a miniaturized biocompatible bypass with an asanguineous prime.

Higher cerebral oxygen saturation may provide higher urinary output during continuous regional cerebral perfusion.

OBJECTIVE: We examined the hypothesis that higher cerebral oxygen saturation (rSO2) during RCP is correlated with urinary output. METHODS: Between December 2002 and August 2006, 12 patients aged 3 to 61 days and weighing 2.6 to 3.4 kg underwent aortic arch repair with RCP. Urinary output and rSO2 were analyzed retrospectively. Data were assigned to either of 2 groups according to their corresponding rSO2: Group A (rSO2 < or = 75%) and Group B (rSO2 < 75%). RESULTS: Seven and 5 patients were assigned to Group A and Group B, respectively.Group A was characterized by mean radial arterial pressure (37.9 +/- 9.6 vs 45.8 +/- 7.8 mmHg; P = 0.14) and femoral arterial pressure (6.7 +/- 6.1 vs 20.8 +/- 14.6 mmHg; P = 0.09) compared to Group B. However, higher urinary output during CPB (1.03 +/- 1.18 vs 0.10 +/- 0.15 ml.kg-1.h-1; P = 0.03). Furthermore our results indicate that a higher dose of Chlorpromazine was used in Group A (2.9 +/- 1.4 vs 1.7 +/- 1.0 mg/kg; P = 0.03). CONCLUSION: Higher cerebral oxygenation may provide higher urinary output due to higher renal blood flow through collateral circulation.

Miniaturized cardiopulmonary bypass system in neonates and small infants.

Cardiopulmonary bypass (CPB) in children is associated with a capillary leak due to inflammatory response, which results in an increase in total body water. This study was designed to reveal that our miniaturized CPB system reduced the peri-operative systemic inflammatory response in small infants. In our institution, the priming volume has been reduced from 500 ml to 140 ml currently. Eighty consecutive patients weighing <5 kg were retrospectively reviewed. The postoperative peak C-reactive protein (CRP), body weight gain (%BWG), and the duration of postoperative mechanical ventilation (MVT) data were collected for each patient. Stepwise multiple logistic regression analyses were used to investigate which of the factors most affected the peri-operative inflammatory responses. A priming volume (coefficient: 0.060, P=0.01), most affected the postoperative peak CRP (mg/dl). A combination of priming volume (coefficient: 0.015, P=0.006), and bypass time (coefficient: 0.013, P=0.028), most affected %BWG (%). A combination of priming volume (coefficient: 0.05, P=0.001) and age (coefficient: -0.02, P=0.001) most affected the MVT (days). The miniaturized circuits reduced the peri-operative inflammatory response, resulting in reduced postoperative systemic edema, and postoperative mechanical ventilation time.

Pediatric cardiac surgery without homologous blood transfusion, using a miniaturized bypass system in infants with lower body weight.

OBJECTIVE: We have established a low-priming volume cardiopulmonary bypass system for pediatric heart surgery to avoid homologous blood transfusion. The priming volume of our system is down to 140 mL for patients weighing less than 7 kg. We can prime the bypass circuits without blood products for patients weighing more than 4 kg. METHODS: Seventy consecutive patients weighing 4 to 7 kg underwent heart surgery with a bloodless prime from October 2003 to September 2006. The type of procedures (Risk Adjustment in Congenital Heart Surgery category) included the following: category 1: atrial septal defect (n = 3); category 2: ventricular septal defect, tetralogy of Fallot, bidirectional Glenn shunt, and others (n = 55); category 3: atrioventricular septal defect, double-outlet right ventricle, and others (n = 8); category 4: Rastelli procedure for transposition of the great arteries (n = 3); and category 6, Damus-Kaye-Stansel procedure (n = 1). Transfusion criteria were hematocrit less than 20%, mixed venous oxygen saturation less than 70%, regional cerebral oxygenation less than 50%, and plasma lactate level greater than 4.0 mmol/L during bypass. RESULTS: The mean age and body weight were 7.3 +/- 5.4 months and 5.4 +/- 0.8 kg, respectively. Forty-five patients (64%) underwent transfusion-free procedures. Preoperative hematocrit, age, body weight, complexity of procedure and cardiopulmonary bypass time were compared between patients with and without transfusion. Bypass time and Risk Adjustment in Congenital Heart Surgery risk category in patients with transfusion were significantly greater than those in patients without (P < .0001, and P < .05, respectively). Body weight in patients without transfusion was significantly greater than that in patients with (P < .01). In multiple regression analysis, the determinants of blood transfusion were the bypass time and body weight (odds ratio 1.026, 95% confidence interval 1.011-.040, P < .0001, and odds ratio 0.366, 95% confidence interval 0.171-0.785, P < .01). CONCLUSIONS: It is possible to do complex transfusion-free procedures safely for patients weighing more than 4 kg by using the low-priming volume circuit. The limiting factors of bloodless heart surgery are not preoperative hematocrit and complexity of procedure but the cardiopulmonary bypass time and the patient's body weight.