New mini-extracorporeal circulation system (ECC.O) is a safe technique in coronary surgery

Objectives. Cardiopulmonary bypass (CPB) is known to cause the systemic inflammatory reaction after cardiac surgery. New coated and closed loop circuit systems may reduce this inflammation response and improve the surgical outcome. This study was designed to evaluate the safety and efficacy of the mini-extracorporeal circulation system (ECC.O) in CABG patients. Design. Forty patients undergoing elective coronary surgery were randomized into two groups, the ECC.O group and the standard CPB group. Routine hemodynamic monitoring and biochemical measurements were registered according to the hospital practice. Results. The clinical outcome of the patients was similar in both groups. There were no significant differences between the groups in the duration of intubation following surgery, the length of intensive care unit-stay or the total hospital stay. The haemoglobin level was significantly higher (p=0.0069) during and after the perfusion in the ECC.O group. Conclusions. The ECC.O system can be safely used in CABG patients and it maintains haemoglobin level better than conventional CPB.     

Comparison of Two Miniaturized Cardiopulmonary Bypass Systems Regarding Inflammatory Response

Cardiopulmonary bypass (CPB) is a known mediator of systemic inflammatory response. Extracorporeal circulations are undergoing continuous modifications and optimizations to achieve better results. Hence we aim to compare the inflammatory response associated with two recent miniature extracorporeal circulation systems during normothermic CPB. We measured plasma levels of cytokines including interleukin (IL)‐1β, IL‐6, IL‐10, tumor necrosis factor‐α, migration inhibitory factor (MIF), receptor for advanced glycation endproduct, and cluster of differentiation 40 ligand in 60 consecutive patients during the first 24 h after CPB. The patients were prospectively randomized to one of three trial groups: patients in group A were operated with the minimal extracorporeal circulation circuit (MECC, Maquet, Rastatt, Germany), group B operated with the extracorporeal circulation circuit optimized (ECC.O, Sorin, Italy), and group C operated with a conventional extracorporeal circuit (CECC, Maquet). Arterial blood samples were collected at intervals before, 30 min after initiation, and after termination of CPB. Further samples were collected 6 and 24 h after CPB. IL‐10 levels were significantly raised in the CECC group as compared with either of the mini ECC‐circuits with a peak concentration at 6 h postoperatively. Human MIF concentrations were significantly higher in the CECC group starting 30 min after CPB and peaking at the end of CPB. The overall reduction in cytokine concentrations in the mini‐ECC groups correlated with a lower need for blood transfusion in MECC and a shorter mechanical ventilation time for ECC.O. Normothermic CPB using minimally invasive extracorporeal circulation circuits can reduce the inflammatory response as measured by cytokine levels, which may be beneficial for perioperative preservation of pulmonary function and hemostasis in low risk patients.     

Effect of cardiopulmonary bypass on cortical cerebral oxygenation during coronary artery bypass grafting.

OBJECTIVE: To investigate the changes in cerebral oxygenation during coronary artery bypass grafting (CABG) with normothermic cardiopulmonary bypass (CPB) using near infrared spectroscopy. METHODS: Measurement of cerebral cortical oxygenation changes included concentration of deoxygenated haemoglobin [HHb], oxygenated haemoglobin [O(2)Hb], changes in the redox status of the cytochrome c oxidase [Cyt-Ox], cerebral saturation as expressed by the tissue oxygenation index (TOI), and cerebral blood volume (CBV) as expressed by tissue haemoglobin index (THI). Measurements were performed in 19 consecutive patients undergoing normothermic (34-36 degrees C) CPB. Data were recorded at 0.5s intervals and averaged into 30 s epochs. Data analysis was carried at baseline, 1, 20, and 40 min after start of CPB, at rewarming, on weaning from CPB, and at closing of chest. RESULTS: There were no in-hospital death, neurological deficits, or myocardial infarcts. Compared to baseline, during the entire CPB duration, there was a marked reduction in [O(2)Hb] and CBV which reached their worst level 40 min after initiation of CPB (from -3.03+/-5.1 to -9.25+/-7.20 micromol/l for [O(2)Hb], and a 24% reduction for CBV (both P<0.0001). The deterioration in [O(2)Hb] was recovered by the end of surgery, while the changes in CBV persisted. No significant changes occurred with respect to [HHb], [Cyt-Ox], and TOI. CONCLUSIONS: Conventional CABG is responsible for deterioration in [O(2)Hb], and CBV, which peak at 40-60 min following initiation of CPB. The changes in [O(2)Hb] are reversible whereas the reduction of CBV persists to the end of the surgery. This suggests a transient impairment in the autoregulatory mechanisms controlling cerebral blood flow following discontinuation of cardiopulmonary bypass.     

Pro-inflammatory cytokines after different kinds of cardio-thoracic surgical procedures: is what we see what we know?

OBJECTIVE: Due to the combination of local trauma, extracorporeal circulation (ECC), and pulmonary and myocardial reperfusion, cardiac surgery leads to substantial changes in the immune system and possibly to post-operative complications. Procedures without ECC, however, have failed to demonstrate clear advantages. We hypothesized that ECC is far less important in this context than the reperfusion/reventilation of the lung parenchyma and the surgical trauma. We therefore conducted a prospective observational study to compare immune reactions after cardiac operations with those after thoracic surgery. METHODS: Serum levels of pro-inflammatory interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-alpha as well as C-reactive protein (CRP), lipoprotein-binding protein (LBP) and procalcitonin (PCT) were measured pre-operatively (d0), at the end of the operation (dx), 6h after the operation (dx+), on the 1st (d1), 3rd (d3), and 5th (d5) post-operative days in 108 patients (pts) undergoing elective coronary artery bypass grafting (CAB) with ECC (n=42, CPB CAB), off-pump coronary artery bypass surgery (n=24, OP CAB) without ECC or thoracic surgery (n=42, TS). RESULTS: After cardiac surgery (CS), IL-6 and IL-8 increased and reached a maximum on dx+. IL-6 returned to baseline values at d3, whereas IL-8 remained elevated until d5. No difference was found between OP CAB and CPB CAB patients. In the TS patients, IL-6 increased later (dx+) and absolute levels were lower than in the CS patients. No increase in IL-8 was noted in the TS patients. Due to the high variation in the results obtained in all three groups, there was no significant change in TNF-alpha. A comparison of TS, OP CAB, and CPB CAB revealed that the CS patients had higher levels on d0, dx, d3, and d5. Serum levels of CRP, LBP, and IL-2R increased from dx+ to d5 in all groups and reached maximum values on d3. Whereas we found no difference in CRP and IL-2R between the groups, LBP levels were significantly higher from dx+ to d3 after OP CAB. PCT was elevated from dx+ to d3 in all pts. Similar levels were noted for the TS and OP CAB patients. The CPB CAB patients showed the highest levels. CONCLUSIONS: Surgical trauma and reperfusion injury appear to represent the predominant factors resulting in immunologic changes after cardiac surgery. Cardiopulmonary bypass (CPB) may be less important for immune response and acute-phase reactions than previously suspected. In addition, our data indicate a relationship between IL-6 synthesis and the degree of surgical trauma. IL-8 appears to be elevated only after cardiac surgery whereas PCT liberation depended on the use of ECC.     

Effects of alveolar recruitment on arterial oxygenation in patients after cardiac surgery: a prospective, randomized, controlled clinical trial

OBJECTIVE: Pulmonary atelectasis and hypoxemia remain considerable problems after cardiac surgery. The objective of this study was to determine the efficacy of consecutive vital capacity maneuvers (C-VCMs) to improve oxygenation in patients after cardiac surgery. STUDY DESIGN: Randomized, controlled clinical trial. SETTING: Tertiary referral teaching center. PARTICIPANTS: Ninety-five patients requiring elective cardiac surgery with cardiopulmonary bypass (CPB). INTERVENTION: Patients were randomly allocated to either C-VCM or control groups. In the C-VCM group, lung inflation at pressure of 35 cmH(2)O was sustained for 15 seconds before separation from CPB and at 30 cmH(2)O for 5 seconds after admission to the intensive care unit (ICU). MEASUREMENTS AND MAIN RESULTS: The primary outcome was the ratio of arterial oxygen tension to inspired oxygen fraction measured at the following predetermined time intervals: after induction of anesthesia, 15 minutes after separation from CPB, after admission to the ICU, after 3 hours of positive-pressure ventilation, after extubation, and before ICU discharge. C-VCM resulted in better arterial oxygenation extending from the immediate postoperative period to approximately 24 hours after surgery at the time of ICU discharge. There were no significant adverse events related to C-VCM application. CONCLUSION: C-VCM is an effective method to reduce hypoxemia associated with the formation of atelectasis after cardiac surgery with CPB.     

Perfusing and ventilating the patient's lungs during bypass ameliorates the increase in extravascular thermal volume after coronary bypass grafting

BACKGROUND: To test the hypothesis that bilateral extracorporeal circulation (ECC) (Drew technique) ameliorates the increase in extravascular thermal volume (ETV) observed after conventional cardiopulmonary bypass (CPB) in patients undergoing coronary artery bypass grafting. METHODS: Thirty-four consecutive patients underwent either bilateral ECC (n = 24, additional cannulation of pulmonary artery and left atrium and lungs perfused and ventilated during bypass) or conventional CPB (n = 10, right atrial and aortic cannulation, lungs statically inflated to 4 mbar (0.41 cm H(2)O) with oxygen, 500 mL/min). Determinations of ETV (thermodye dilution technique) and intraoperative fluid balance were made before surgery, at the end of surgery, and 4 hours thereafter. In addition, interleukin (IL)-8, thromboxane B2 (TxB(2)), and endothelin (ET)-1 concentrations were measured in the right atrium and pulmonary vein at specified time points. RESULTS: Comparisons of ETV made at the start of surgery, after aortic declamping, and after termination of ECC, respectively, revealed an increase from 4.8 +/- 0.2 mL/kg (mean +/- SEM) to 6.7 +/- 0.4 mL/kg, and 6.3 +/- 0.3 mL/kg with conventional CPB but ETV remained unchanged at 5.2 +/- 0.3 mL/kg, 5.1 +/- 0.2 mL/kg, and 4.9 +/- 0.3 mL/kg with bilateral ECC. Priming volume (1,580 +/- 10 mL versus 2,213 +/- 77 mL, p < 0.001) and intraoperative fluid balance (+1,955 +/- 233 mL versus +2,654 +/- 210 mL, p < 0.05) were less with conventional CPB. Concentrations of IL-8, TxB(2), and ET-1 were not different between groups. CONCLUSIONS: Despite a significantly greater prime volume and a more positive intraoperative fluid balance, ETV did not change with bilateral ECC but increased with conventional CPB. Thus, using the patient's lungs as an oxygenator during bypass mitigates the increase in extravascular pulmonary fluid.     

Does normoxemic cardiopulmonary bypass prevent myocardial reoxygenation injury in cyanotic children?

OBJECTIVE: To evaluate whether the deleterious effect of cardiopulmonary bypass (CPB) can be prevented by controlling PaO(2) in cyanotic children. DESIGN: Prospective, randomized, clinical study. SETTING: Single university hospital. PARTICIPANTS: Pediatric patients undergoing cardiac surgery for repair of congenital heart disease (n = 24). INTERVENTIONS: Patients were randomly allocated into 3 groups. Patients in the acyanotic group (group I, n = 10) had CPB initiated at a fraction of inspired oxygen (F(I)O(2)) of 1.0 (PO(2), 300 to 350 mmHg). Cyanotic patients were subdivided as follows: Group II (n = 7) had CPB initiated at an F(I)O(2) of 1.0, and group III (n = 7) had CPB initiated at an F(I)O(2) of 0.21 (PO(2), 90 to 110 mmHg). A biopsy specimen of right atrial tissue was removed during venous cannulation, and another sample was removed after CPB before aortic cross-clamping. The tissue was incubated in 4 mmol/L of t-butylhydroperoxide, and the malondialdehyde (MDA) level was measured to determine the antioxidant reserve capacity. Blood samples for cytokine levels, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-6 response to CPB were collected after induction of anesthesia and at the end of CPB before protamine administration. MEASUREMENTS AND MAIN RESULTS: After initiation of CPB, MDA level rose markedly in the cyanotic groups compared with the acyanotic group (210 +/- 118% v 52 +/- 34%, p < 0.05), which indicated the depletion of antioxidants. After initiation of CPB, TNF-alpha and IL-6 levels of the cyanotic groups were higher than for the acyanotic group (168 +/- 77 v 85 +/- 57, p < 0.001; 249 +/- 131 v 52 +/- 40; p < 0.001). When a comparison between the cyanotic groups was performed, group II (initiating CPB at an F(I)O(2) of 1.0) had significantly increased MDA production compared with group III (initiating CPB at an F(I)O(2) of 0.21) (302 +/- 134% v 133 +/- 74%, p < 0.05). Group II had higher TNF-alpha and IL-6 levels than group III (204 +/- 81 v 131 +/- 52, p < 0.001; 308 +/- 147 v 191 +/- 81, p < 0.01). CONCLUSION: Conventional clinical methods of initiating CPB at a hyperoxemic PO(2) may increase the possibility of myocardial reoxygenation injury in cyanotic children. This deleterious effect of reoxygenation can be modified by initiating CPB at a lower level of oxygen concentration. Subsequent long-term studies are needed to determine the best method of decreasing the oxygen concentration of the CPB circuit.     

Extracorporeal circulation, optimized: a pilot study

We designed a pilot study to assess as primary end point the safety and efficacy of a new phosphorylcholine-coated, closed cardiopulmonary bypass (CPB) system (extracorporeal circulation, optimized [ECC.O], Dideco, Mirandola, Italy). The secondary end point was to compare results with two retrospectively matched cohorts of patients who underwent isolated coronary artery by-pass graft (CAGB) with nonphosphorylcholine-bonded circuits and cardiotomy suction (Group II, n = 32) and off-pump coronary artery by-pass (OPCAB) (Group III, n = 26). In January 2005, 30 patients (Group I) undergoing first-time CABG were assigned to the ECC.O group. Five minutes after CPB, initial hematocrit levels were significantly and consistently highest in Group I relative to Group II (Group I, 29.7 +/- 4.4 vs. Group II, 22.7 +/- 4.1; P < 0.001). Red blood cell transfusion rate was reduced drastically in Group I versus Group II (P < 0.001). High differences were also observed in C-reactive protein levels at 24 h after surgery (Group I vs. Group II-P < 0.001 and vs. Group III-P < 0.001) and at 72-h peak value (Group I vs. Group II-P < 0.001 and vs. Group III-P < 0.001). The routine clinical use of the ECC.O system has been demonstrated to be both clinically safe and efficacious. An intensive training program for surgeons, perfusionists, and anesthesiologists is required.     

Extracorporeal circulation for rewarming in drowning and near-drowning pediatric patients

Drowning and near-drowning is often associated with severe hypothermia requiring active core rewarming.We performed rewarming by cardiopulmonary bypass(CPB). Between 1987 and 2007, 13 children (9 boys and 4 girls) with accidental hypothermia were rewarmed by extracorporeal circulation (ECC) in our institution. The average age of the patients was 3.2 years. Resuscitation was started immediately upon the arrival of the rescue team and was continuously performed during the transportation.All patients were intubated and ventilated. Core temperature at admission ranged from 20 to 29°C (mean 25.3°C). Connection to the CPB was performed by thoracic (9 patients) or femoral/iliac means (4 patients). Restoration of circulation was achieved in 11 patients (84.6%). After CPB termination two patients needed an extracorporeal membrane oxygenation system due to severe pulmonary edema.Five patients were discharged from hospital after prolonged hospital stay. During follow-up, two patients died(10 and 15 months, respectively) of pulmonary complications and one patient was lost to follow-up. The two remaining survivors were without neurological deficit.Modes of rewarming, age, sex, rectal temperature, and serum electrolytes did not influence mortality. In conclusion,drowning and near-drowning with severe hypothermia remains a challenging emergency. Rewarming by ECC provides efficient rewarming and full circulatory support.Although nearly half of the children may survive after rewarming by ECC, long-term outcome is limited by pulmonary and neurological complications.     

Effects of perfusion pressure on cerebral blood flow and oxygenation during normothermic cardiopulmonary bypass

BACKGROUND: Central nervous system dysfunction after cardiopulmonary bypass (CPB) is an important cause of morbidity and mortality after cardiac surgery. Perfusion pressure (PP) during CPB could be one of the important determinants of cerebral blood flow (CBF). The objective of the present study was to determine the effect of PP on CBF and cerebral oxgenation during normothermic CPB. METHODS: Twelve adult patients undergoing coronary artery bypass graft surgery were randomly assigned to one of two groups based on PP (High and Low group). Patients in High group received phenylephrine immediately after the onset of CPB to maintain PP between 60 and 80 mmHg. Oxyhemoglobin (O2Hb), deoxyhemoglobin (HHb), tissue oxygenation index (TOI), and oxidized cytochrome aa3 (CtOx) were measured by near-infrared spectroscopy, and internal jugular venous bulb blood oxygen saturation (SjvO2) was measured simultaneously. S-100 beta protein concentrations were also measured before and after CPB. RESULTS: SjvO2 in High group increased significantly during CPB. CtOx in Low group decreased significantly during CPB, whereas TOI was unchanged. Although S-100 beta increased significantly at the end of CPB, there was no difference between the groups. CONCLUSIONS: These results suggest that maintaining high PP is benefical for CBF during normothermic CPB.     

High oxygen concentration exacerbates cardiopulmonary bypass-induced lung injury

OBJECTIVE: To investigate the effect of ventilation with 100% oxygen on lung injury associated with surgery involving cardiopulmonary bypass (CPB). DESIGN: A prospective randomized study. SETTING: University hospital. PARTICIPANTS: Thirty patients undergoing coronary artery bypass graft surgery with CPB. INTERVENTIONS: Patients were randomized to receive 100% oxygen (Oxygen group) or 50% oxygen (Air group) throughout surgery. During CPB, patients' lungs in the Air group were flushed with air and in the Oxygen group with 100% oxygen. MEASUREMENTS AND MAIN RESULTS: Lung injury was evaluated by arterial oxygen tension-inspired oxygen concentration (PaO2-FIO2) ratio and cytokine levels (tumor necrosis factor-alpha and interleukin-8) in blood and bronchoalveolar lavage fluid measured before and after CPB. The lowest PaO2-FIO2 value was observed after 40 minutes following the completion of CPB in both groups. PaO2-FIO2 values 6 hours after CPB were not different from baseline in the Air group but remained lower (359+/-63 mmHg and 298+/-78 mmHg; p = 0.013) in the Oxygen group. Blood cytokine levels rose during surgery in both groups. Bronchoalveolar lavage levels of interleukin-8 did not change, whereas tumor necrosis factor-alpha increased only in the Oxygen group (p = 0.035). CONCLUSIONS: A significant decrease of oxygenation was observed in the early post-CPB period in both groups of patients, with delay in recovery in patients treated with 100% oxygen. A larger increase of the proinflammatory cytokines was found in patients treated with 100% oxygen. High oxygen concentrations during surgery with CPB should be used only when specifically required.     

The effect of leucodepletion on leucocyte activation, pulmonary inflammation and respiratory index in surgery for coronary revascularisation: a prospective randomised study.

OBJECTIVE: Leucocyte activation is central to end-organ damage that occurs during cardiac surgery under cardiopulmonary bypass (CPB). Exhaled nitric oxide (NO) increases in inflammatory lung conditions and has been proposed as a marker of pulmonary inflammation during CPB. This study examined the effect of leucodepletion on leucocyte activation, pulmonary inflammation and oxygenation in patients undergoing coronary revascularisation. METHODS: Fifty low-risk patients undergoing first time coronary artery bypass graft (CABG) were randomised to two groups. Twenty-five patients had an arterial line leucocyte-depleting filter and 25 controls had a standard filter. Arterial blood samples were taken before CPB, 5 and 30 min on CPB, 5 min after aortic clamp removal and 6 h post-operatively. Activated leucocytes were identified with Nitroblue Tetrazolium staining. NO was sampled via an endotracheal teflon tube 15 min after median sternotomy before CPB and 30 min after discontinuation of CPB using a real-time chemiluminescense analyser. Respiratory index (alveolar-arterial oxygenation index, AaOI) was calculated before CPB, 1, 2, 4, 8 and 18 h post-operatively. Clinical outcome end-points were also recorded. RESULTS: Total and activated leucocyte counts were significantly lower following leucodepletion during CPB (P < 0.0001). Exhaled NO rose significantly after CPB in the control group (3.8+/-1 ppb/s before CPB vs 5.6+/-2 ppb/s after CPB (P = 0.003) but not in the leucodepleted group (3.7+/-1 ppb/s before CPB vs 3.9+/-1 ppb/s after CPB (P = 0.051). AaOIs were consistently lower after leucodepletion (anova, P = 0.001). The duration of mechanical ventilation, the intensive care and hospital stay and the frequency of cardiac and respiratory complications were similar in the two groups. CONCLUSIONS: Leucodepletion reduces the numbers of circulating activated leucocytes and the pulmonary inflammation during CPB. This appears to limit lung injury and improve oxygenation in low-risk patients undergoing CABG surgery. Larger numbers of patients are required to evaluate the effect of continuous arterial line leucodepletion on the clinical outcome.     

Influence of a vital capacity maneuver on pulmonary gas exchange after cardiopulmonary bypass.

OBJECTIVE: To investigate the effect of a single, vital capacity breath (vital capacity maneuver [VCM]), administered at the end of cardiopulmonary bypass (CPB), on pulmonary gas exchange in patients undergoing coronary artery bypass graft surgery. DESIGN: Prospective, randomized, double-blind study. SETTING: University-affiliated hospital. PARTICIPANTS: Forty patients scheduled for elective coronary artery bypass graft surgery and early tracheal extubation. INTERVENTIONS: Patients were randomized to 1 of 2 groups. VCM patients received a VCM at the conclusion of CPB. Control patients received no VCM. MEASUREMENTS AND MAIN RESULTS: Intrapulmonary shunt (Q(S)/Q(T)), arterial oxygenation (PaO2), and alveolar-arterial oxygen gradients (P(A-a)O2) were measured after induction of anesthesia, CPB, intensive care unit (ICU) arrival, and extubation. The duration of postoperative intubation was recorded for each group. Q(S)/Q(T) increased significantly 30 minutes after CPB in the control group (15.7 +/- 1.8% to 27.4 +/- 2.6%; p = 0.01). In the VCM group, a small decrease in Q(S)/Q(T) occurred (16.1 +/- 2.0% to 14.9 +/- 2.0%). After ICU arrival and extubation, no significant difference in Q(S)/Q(T) existed between the 2 groups. With the exception of a higher P(A-a)O2 in the control group at induction of anesthesia, no differences in PaO2 or P(A-a)O2 were present between the 2 groups at any measurement interval. Patients who received a VCM were extubated earlier than the control group (6.5 +/- 2.1 hours v 9.4 +/- 4.2 hours; p = 0.01). CONCLUSION: The use of a VCM prevented an increase in Q(S)/Q(T) from occurring in the operating room. Although a VCM did not influence pulmonary gas exchange in the ICU, its application in the operating room appears to exert a beneficial effect on tracheal extubation times after cardiac surgery.     

Comparative study on cerebral injury after open heart surgery in patients with congenital and rheumatic heart disease

Alongwiththedevelopmentofscienceandtechnology,intracardiacoperationsbecomemuchsaferthanever.Althoughthemortalityrateofthepatientsreceivingintracardiacoperationwith helpofcardiopulmonarybypass(CPB)hasdecreased butneurologicalcomplicationsoccurfrequently.Neurologicalcomplicationshavebeenidentifiedsince theearlydayswhenemployingcardiacsurgery.1And neurologicalcomplicationsaftertheemploymentofCPB areimportantfatalcomplicationsofnon cardiovascular originatpresent.2Theincidenceofneuropsychologica…     

Normothermic versus hypothermic cardiopulmonary bypass during repair of congenital heart disease.

OBJECTIVE: To compare normothermic cardiopulmonary bypass (CPB) versus hypothermic CPB in pediatric patients undergoing repair of congenital heart disease with focus on biochemical markers for brain damage. DESIGN: Prospective randomized interventional study. SETTING: Postgraduate teaching hospital. PARTICIPANTS: Twenty patients undergoing repair of congenital heart disease. INTERVENTIONS: Patients were randomized to normothermic (36 degrees C) versus hypothermic (25 degrees C) CPB. Serum levels of neuron-specific enolase (NSE) and S-100beta protein were measured in all patients before surgery, immediately after CPB, and 12 and 24 hours after surgery. Blood loss and time for extubation of the trachea were recorded. MEASUREMENTS AND MAIN RESULTS: Before operation, the S-100beta protein and NSE levels were similar in the 2 groups. The S-100beta protein serum level increased significantly after CPB in both groups, whereas no change was found in the NSE level. There was no difference in the change of NSE and S-100beta protein levels between normothermic and hypothermic CPB. Blood loss was significantly less after hypothermic CPB (25 mL/kg/24 h v 42 mL/kg/24 h). Time for extubation was similar. CONCLUSION: No difference was found in the release of brain-specific proteins between normothermic and hypothermic CPB, but blood loss was higher after normothermic CPB.     

麻醉药物对成人患者心脏术后肺部并发症的影响

目的 评估术中麻醉维持药物(吸入麻醉药或静脉麻醉药)对体外循环下成人心脏手术患者术后肺部并发症(postoperative pulmonary complications,PPCs)的影响.方法 从四川大学华西医院电子病历信息管理系统及麻醉手术临床信息系统中回顾性筛选2018年9月至2019年2月194例行择期体外循环...     

A prospective, randomized study of endothelin and postoperative recovery in off-pump versus conventional coronary artery bypass surgery

OBJECTIVE: The objectives are 2-fold: (1). to serially determine endothelin (ET) levels in arterial vascular compartments in patients undergoing coronary artery bypass surgery using either cardiopulmonary bypass or off-pump techniques, and (2). to define potential relationships between endothelial levels and specific perioperative parameters of patient recovery. METHODS: In a prospective, randomized study, endothelin plasma content was measured from patients undergoing coronary artery bypass grafting using either off-pump techniques (OPCAB group, n = 25) or conventional cardiopulmonary bypass (CPB group, n = 25) before surgery, before and after coronary artery anastomosis, and 6 and 24 hours postoperatively. Specific indices of patient recovery including pulmonary artery pressures, ventilation requirement, and hospital stay were documented for patients in both study groups. RESULTS: Postoperative systemic arterial ET levels were significantly increased by 200% in the CPB group and 50% in the OPCAB group. ET levels remained significantly higher in the CPB group relative to the OPCAB group throughout the postoperative period of observation (p < 0.05). Pulmonary artery pressures, ventilation requirement, and hospital stay were significantly increased in patients in the CPB group. CONCLUSIONS: Postoperative ET levels were higher in patients who underwent CPB for coronary artery bypass surgery. Increased ET in the postoperative period may contribute to a more complex recovery from coronary artery bypass surgery in patients undergoing cardiopulmonary bypass.     

Morbidity and mortality after autotransfusion following open heart surgery

Background

The technique of ‘blood pooling’ before the onset of cardiopulmonary bypass (CPB) has been shown to be beneficial as a single technique in patients having elective open heart surgery. We sought to more clearly evaluate the role of intra-operative autologous donation also known as acute normovolemic haemodilution in open heart surgery.

Methods

The study was conducted in the Department of Cardiothoracic and Vascular Surgery, King George’s Medical University, Lucknow, India, in patients who underwent open heart surgery under cardiopulmonary bypass. Autologous blood transfusion was used in all the patients who underwent surgery on CPB since August 2009. Patients were divided into two groups: group I (study group)—patients operated between August 2009 and December 2011 and who received autologous blood and group II (control)—those operated before August 2009 and who did not receive autologous blood transfusion.

Results

The post-operative haemoglobin and coagulation profile measured on the first post-operative day differed significantly between the two groups. Intensive care unit (ICU) stay, hospital stay, inotropic support and ventilatory support were significantly less in group 1. Mediastinal drainage was found to be significantly higher in the control group compared to the study group. The mean volume of packed red blood cell, fresh frozen plasma and platelet units transfused per patient in the study group were significantly less than the control group.

Conclusion

The use of intra-operative autologous blood donation and transfusion improves haemostasis, decreases the post-operative blood loss and improves the post-operative outcome in terms of intensive care unit stay, hospital stay, morbidity and mortality.     

Effect of respiratory care on pulmonary function in patients after cardiopulmonary bypass

BACKGROUND: Respiratory failure after cardiopulmonary bypass (CPB) remains one of the major complications after cardiac surgery. This study was designed to evaluate effects of respiratory care after CPB on pulmonary function. METHODS: Eighteen patients scheduled for cardiac surgery were investigated. Preoperative respiratory functions (%VC, FEV1.0%, V25/Ht, FRC-CC, deltaN2) were measured in all the patients. Both induction and maintenance of anesthesia were performed using propofol, midazolam, fentanyl, and vecuronium bromide. All the patients were ventilated using volume controlled ventilation by setting FIO2 at 0.5, the respiratory frequency at 15 x min(-1), the tidal volume at 6-10 ml x kg(-1) adjusted to maintain PaCO2 between 30 to 40 mmHg, and the peak airway pressures below 40 cmH2O, PEEP of 0 cmH2O. From 1 hour after the operation, the patients were randomly divided into 2 groups: group A, ventilated artificially with PEEP of 5 cmH2O and group B, ventilated with PEEP adjusted to the patient's lower inflection point (LIP) obtained by the pressure-volume curve. PaO2, Qs/Qt and FRC were measured after induction of anesthesia, just after surgery, 1 hour after surgery and 1 hour after artificial ventilation with PEEP. The values of the LIP were obtained from the P-V curves with the constant-flow methods before and after surgery. RESULTS: PaO2 and FRC decreased and Qs/Qt increased significantly after the surgery in all the patients. One hour after artificial ventilation with PEEP, PaO2 increased and Qs/Qt decreased significantly compared with the values after operation. However, there was no significant difference in the magnitude of these changes among the different groups. The changes in PaO2 and Qs/Qt were not correlated with the changes in FRC and preoperative respiratory functions. The LIP tended to increase after surgery in 2 groups. CONCLUSIONS: Although pulmonary function deteriorated after CPB. PEEP could improve oxygenation in all the patients. There were no significant differences in the degree of these improvements between patients receiving PEEP of 5 cmH2O and patients with PEEP adjusted to their LIP. There was no significant relationship between preoperative pulmonary function and changes in oxygenation after CPB.     

Efficacité respective du Cell Saver ® et de la récupération du circuit de CEC ultrafiltré en chirurgie cardiaque

The efficiency of two intraoperative techniques of blood saving were compared prospectively. During a period of eight months, in 120 adults patients undergoing heart surgery with a cardiopulmonary bypass (CPB). They all had blood removed before the start of CPB for isovolaemic haemodilution. They were randomly assigned to two groups (n = 60 for each): for group A patients, blood was salvaged during surgery before the start of the CPB, during cardioplegia, and from the CPB circuit at the end of surgery, using a Cell Saver 1V (Haemonetics), and returned to the patient in theatre or in intensive care; in group B patients, blood in the CPB circuit at the end of surgery was ultrafiltered and returned to the patient at the same time as 0.8 mg.kg-1 protamine sulfate. The same anaesthetic protocol was used in all the patients (flunitrazepam, phenoperidine and pancuronium bromide). There was no significant difference between the two groups in the volume of blood removed at the start of surgery (9.12 +/- 2.01 ml.kg-1 (A) vs. 8.85.2.22 ml.kg-1 (B)), in the amounts of replacement fluid (Haemaccel, 4% albumin) given to maintain volaemia, and in postoperative blood loss Red cell count, haemoglobin level and haematocrit were higher in the Cell Saver group at the third postoperative hour and on the first postoperative day, whereas fibrinogen levels and platelet count were higher in the ultrafiltration group at the same times. A mean of 1.02 +/- 1.71 homologous blood units were given to group A and 1.45 +/- 1.71 in group B (not significant).(ABSTRACT TRUNCATED AT 250 WORDS)