Adipose tissue is inflamed in NAFLD due to obesity but not in NAFLD due to genetic variation in PNPLA3.

AIMS/HYPOTHESIS: The rs738409 C>G single-nucleotide polymorphism in PNPLA3 leads to a missense mutation (I148M) which increases liver fat but does not cause insulin resistance. We hypothesised that patients with non-alcoholic fatty liver disease (NAFLD) due to the PNPLA3 variant ('PNPLA3 NAFLD' = PNPLA3-148MM) do not have adipose tissue (AT) inflammation in contrast with those with NAFLD due to obesity ('obese NAFLD'). METHODS: Biopsy specimens of AT were taken, and PNPLA3 genotype and liver fat ((1)H-magnetic resonance spectroscopy) were determined in 82 volunteers, who were divided into groups based on either median BMI (obese 36.2 ± 0.7 kg/m(2); non-obese 26.0 ± 0.4 kg/m(2)) or PNPLA3 genotype. All groups were similar with respect to age and sex. The PNPLA3 subgroups were equally obese (PNPLA3-148MM, 31.1 ± 1.3 kg/m(2); PNPLA3-148II, 31.2 ± 0.8 kg/m(2)), while the obese and non-obese subgroups had similar PNPLA3 genotype distribution. Gene expression of proinflammatory (MCP-1, CD68) and anti-inflammatory (Twist1, ADIPOQ) markers was measured using quantitative real-time RT-PCR. RESULTS: Liver fat was similarly increased in obese NAFLD (9.5 ± 1.3% vs 5.1 ± 0.9%, obese vs non-obese, p = 0.007) and PNPLA3 NAFLD (11.4 ± 1.7% vs 5.3 ± 0.8%, PNPLA3-148MM vs PNPLA3-148II, p < 0.001). Fasting serum insulin was higher in the obese than the non-obese group (76 ± 6 vs 47 ± 6 pmol/l, p < 0.001), but similar in PNPLA3-148MM and PNPLA3-148II (60 ± 8 vs 62 ± 5 pmol/l, NS). In obese vs non-obese, MCP-1 and CD68 mRNAs were upregulated, whereas those of Twist1 and ADIPOQ were significantly downregulated. AT gene expression of MCP-1, CD68, Twist1 and ADIPOQ was similar in PNPLA3-148MM and PNPLA3-148II groups. CONCLUSIONS/INTERPRETATION: PNPLA3 NAFLD is characterised by an increase in liver fat but no insulin resistance or AT inflammation, while obese NAFLD has all three of these features.

Corticosteroid therapy in intensive care unit patients with PCR-confirmed influenza A(H1N1) infection in Finland.

OBJECTIVE: To evaluate the incidence, treatment, and outcome of influenza A(H1N1) in Finnish intensive care units (ICUs) with special reference to corticosteroid treatment. METHODS: During the H1N1 outbreak in Finland between 11 October and 31 December 2009, we prospectively evaluated all consecutive ICU patients with high suspicion of or confirmed pandemic influenza A(H1N1) infection. We assessed severity of acute disease and daily organ dysfunction. Ventilatory support and other concomitant treatments were evaluated and recorded daily throughout the ICU stay. The primary outcome was hospital mortality. RESULTS: During the 3-month period altogether 132 ICU patients were tested polymerase chain reaction-positive for influenza A(H1N1). Of these patients, 78% needed non-invasive or invasive ventilatory support. The median (interquartile) length of ICU stay was 4 [2-12] days. Hospital mortality was 10 of 132 [8%, 95% confidence interval (CI) 3-12%]. Corticosteroids were administered to 72 (55%) patients, but rescue therapies except prone positioning were infrequently used. Simplified Acute Physiology Score II and Sequential Organ Failure Assessment scores in patients with and without corticosteroid treatment were 31 [24-36] and 6 [2-8] vs. 22 [5-30] and 3 [2-6], respectively. The crude hospital mortality was not different in patients with corticosteroid treatment compared to those without: 8 of 72 (11%, 95% CI 4-19%) vs. 2 of 60 (3%, 95% CI 0-8%) (P = 0.11). CONCLUSIONS: The majority of H1N1 patients in ICUs received ventilatory support. Corticosteroids were administered to more than half of the patients. Despite being more severely ill, patients given corticosteroids had comparable hospital outcome with patients not given corticosteroids.

N-terminal-pro-BNP in critically ill patients with acute respiratory failure: a prospective cohort study.

BACKGROUND: The aim of this study was to evaluate the prognostic value of plasma N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) in unselected critically ill patients with acute respiratory failure (ARF). METHODS: Prospective, observational cohort study in 25 intensive care units in Finland. This study included a total of 602 patients with laboratory samples from 958 consecutive patients with ARF treated either with invasive or with non-invasive ventilatory support (the FINNALI study). Plasma NT-pro-BNP samples were drawn after the onset of ventilatory support (day 0) and on the morning of the second day. RESULTS: The median [interquartile ranges (IQR)] NT-pro-BNP-values were significantly higher at baseline in 90-day non-survivors than the survivors, 4378 pg/ml (1400-13,943 pg/ml) vs. 1052 pg/ml (232-4076 pg/ml), respectively. The median (IQR) NT-pro-BNP values were significantly higher in patients with chronic cardiac disease or cardiac surgery than in non-cardiac patients, 1947 pg/ml (801-4687 pg/ml) vs. 417 pg/ml (153-1735 pg/ml), respectively, if renal function was normal. With deteriorating renal function, the NT-pro-BNP values showed a significant increase. The area under curve for baseline NT-pro-BNP predicting 90-day mortality was moderate: 0.718 (95% confidence interval 0.674-0.761). Baseline NT-pro-BNP over 1765 pg/ml was independently associated with 90-day mortality by logistic regression analysis (P<0.001). CONCLUSIONS: NT-pro-BNP on admission is commonly elevated and independently associated with 90-day mortality in critically ill ARF patients. However, the routine use of NT-pro-BNP for prognostic purpose does not seem to add value to clinical data in ARF patients.

Immune response after laparoscopic and conventional Nissen fundoplication.

OBJECTIVE: To compare the changes in the immune responses of patients undergoing laparoscopic or conventional Nissen fundoplication. DESIGN: Prospective randomised clinical study. SETTING: University hospital, Finland. SUBJECTS: 20 patients undergoing Nissen fundoplication for symptomatic erosive oesophagitis. INTERVENTION: Laparoscopic Nissen fundoplication (n = 10) or conventional open Nissen fundoplication (n = 10). MAIN OUTCOME MEASURES: Leucocyte and differential counts; percentages of lymphocyte subpopulations (CD3, CD4, CD8, CD16 and CD20 positive lymphocytes); and monocytes (CD 14); phytohemagglutinin, concanavalin A and pokeweed mitogen-induced and unstimulated proliferation of separated lymphocytes; plasma interleukin-6 (IL-6), serum C-reactive protein (CRP), albumin, and cortisol concentrations; and group II phospholipase A2 (PLA2) activity. RESULTS: Laparoscopic fundoplication was associated with less tissue damage (IL-6, and CRP concentrations) than the conventional open operation. However, although there were pronounced changes in immune responses over time, there were no differences between the groups. CONCLUSION: Laparoscopic fundoplication seemed to cause less tissue damage than the conventional open operation, but this difference was not reflected in patients' immune responses.

Effects of open heart surgery on oral mucous host defence systems.

BACKGROUND: The immune response is affected by anaesthesia and surgery. This study was carried out on the effects of open heart surgery on the oral mucous host defence system, which is part of the common mucosal immune system. METHODS: Amylase, nonimmunological (lysozyme, myeloperoxidase, hypothiocyanite and thiocyanate) and immunological (IgA, IgG, and IgM) mucous host defence factors as well as oral bacterial flora were determined in the saliva of 18 patients undergoing open heart surgery preoperatively and on the 2nd, 3rd, and 7th postoperative days. To assess the specificity of the changes, the salivary flow rate and total protein content were also determined. RESULTS: Stimulated salivary flow decreased from 1.8 (1.3-2.2) ml/min (median; 25th and 75th quartiles) to 0.4 (0.3-0.5) ml/min by the 2nd postoperative day and to 0.4 (0.2-1.0) ml/min by the 3rd postoperative day (P < 0.001). Amylase, lysozyme, myeloperoxidase, total salivary peroxidase and thiocyanate levels increased, whereas hypothiocyanite levels decreased postoperatively (p < 0.01-0.001). Their total secretion rate, however, was reduced (P < 0.05-0.001) owing to the lowered salivary flow rate. IgG and IgM concentrations were raised on the 2nd, 3rd and 7th postoperative days (P < 0.05-0.001), and IgA concentrations on the 2nd postoperative day (P < 0.05). The total secretion of IgG and IgM as well as their salivary concentrations in relation to total protein concentrations also increased. The number of salivary anaerobically growing bacteria decreased postoperatively (P < 0.01), but the number of salivary streptococci remained unaffected. CONCLUSIONS: Open heart surgery decreases the salivary secretion of nonimmunological host defence factors and increases the salivary secretion of IgA, IgG and IgM.

Enhanced spontaneous antibody response after coronary artery bypass surgery.

PURPOSE: Cells spontaneously secreting immunoglobulins can be seen in the blood one week after open-heart surgery. The purpose of this study was to measure the antibody specificities of activated cells. METHODS: Immune responses were studied preoperatively and on the seventh postoperative day in 18 patients undergoing elective coronary artery bypass surgery. The number of cells secreting adenovirus, measles, rubella and tetanus antigen specific antibodies spontaneously and induced by pokeweed mitogen PWM (ASCs) as well as the total number of cells secreting IgG, IgM and IgA (ISCs) were studied using an enzyme-linked immunospot (ELISPOT) assay. Spontaneous as well as phytohaemagglutinin (PHA)- and pokeweed mitogen (PWM)-induced lymphocyte proliferation was also measured. RESULTS: The number of cells spontaneously secreting IgG, IgM and IgA antibodies was increased on the seventh day after coronary bypass surgery, against adenovirus, measles, rubella and tetanus as well as the total number of cells secreting immunoglobulins IgG, IgM and IgA (P < 0.05/0.001). By contrast, only slight fluctuation was seen in the numbers of cells secreting antibodies after PWM stimulation. Spontaneous lymphocyte proliferation was also increased, PHA proliferative responses were depressed and PWM responses were not changed on the seventh postoperative day compared with preoperative values. CONCLUSION: Coronary artery bypass surgery caused marked polyclonal B cell activation demonstrated by an increase of cells producing spontaneously antibodies against virus antigens and tetanus toxoid. This activation could not be intensified by PWM stimulation.

Dexmedetomidine as an anesthetic adjunct in coronary artery bypass grafting.

BACKGROUND: Alpha 2-adrenergic agonists decrease sympathetic tone with ensuing attenuation of neuroendocrine and hemodynamic responses to anesthesia and surgery. The effects of dexmedetomidine, a highly specific alpha 2-adrenergic agonist, on these responses have not been reported in patients undergoing coronary artery bypass grafting. METHODS: Eighty patients scheduled for elective coronary artery bypass grafting received, in a double-blind manner, either a saline placebo or a dexmedetomidine infusion, initially 50 ng.kg-1.min-1 for 30 min before induction of anesthesia with fentanyl, and then 7 ng.kg-1.min-1 unit the end of surgery. Filling pressures, blood pressure, and heart rate were controlled by intravenous fluid and by supplemental anesthetics and vasoactive drugs. RESULTS: Compared with placebo, dexmedetomidine decreased plasma norepinephrine concentrations by 90%, attenuated the increase of blood pressure during anesthesia (3 vs. 24 mmHg) and surgery (2 vs. 14 mmHg), but increased slightly the need for intravenous fluid challenge (29 vs. 20 patients) and induced more hypotension during cardiopulmonary bypass (9 vs. 0 patients). Dexmedetomidine decreased the incidence of intraoperative (2 vs. 13 patients) and postoperative (5 vs. 16 patients) tachycardia. Dexmedetomidine also decreased the need for additional doses of fentanyl (3.1 vs. 5.4), the increments of enflurane (4.4 vs. 5.6), the need for beta blockers (3 vs. 11 patients), and the incidence of fentanyl-induced muscle rigidity (15 vs. 33 patients) and postoperative shivering (13 vs. 23 patients). CONCLUSIONS: Intraoperative intravenous infusion of dexmedetomidine to patients undergoing coronary artery revascularization decreased intraoperative sympathetic tone and attenuated hyperdynamic responses to anesthesia and surgery but increased the propensity toward hypotension.

Splanchnic and peripheral tissue perfusion in experimental fat embolism.

OBJECTIVE: To investigate the acute effects of experimental fat embolism on splanchnic and peripheral perfusion and oxygenation in pigs. DESIGN: Randomized, controlled trial. SETTING: Animal laboratory. SUBJECTS: Eighteen domestic pigs, weighing 25 to 31 kg. INTERVENTIONS: The 18 pigs were randomized to either the fat embolism or control groups. Nine anesthetized and mechanically ventilated pigs were intracavally infused with a 10% allogeneic bone marrow suspension at a dose of 100 mg/kg over 5 mins (the fat embolism group); nine control pigs received normal saline in the same volume and speed (control group). MEASUREMENTS AND MAIN RESULTS: Mean pulmonary arterial pressure, pulmonary vascular resistance, and pulmonary shunt increased, and PaO2 decreased immediately after the bone marrow suspension infusion. In the fat embolism animals, oxygen delivery decreased, oxygen content difference widened, and total oxygen consumption remained high, indicating enhanced oxygen extraction. Further, superior mesenteric artery blood flow and mesenteric oxygen delivery decreased, while intramucosal pH in the small bowel was stable. Subcutaneous PO2 decreased in both groups, whereas transcutaneous PO2 decreased only in the animals receiving bone marrow suspension. Skin red cell flux showed no significant changes. CONCLUSIONS: The present model of fat embolism results in significant impairment in systemic oxygenation. Despite this fact, the intestinal oxygenation remains unaffected probably due to sufficient compensatory mechanisms. Transcutaneous PO2 measurements may provide a useful index for early detection of fat embolism.

Phospholipases A2 in the serum of patients after coronary artery bypass surgery.

OBJECTIVE: To study the catalytic activity of phospholipase A2 and the concentrations of group I and group II phospholipase A2 in the sera of patients during and after coronary artery bypass surgery. DESIGN: Prospective study. SETTING: University hospital and research laboratory. PATIENTS: Fourteen consecutive patients operated on for ischemic heart disease. INTERVENTIONS: The catalytic activity of phospholipase A2 and the serum concentrations of group I and group II phospholipases A2 were measured before, during, and after the operation until the seventh postoperative day. A total of 196 blood samples were taken from 14 patients. MEASUREMENTS AND MAIN RESULTS: The catalytic activity of phospholipase A2 and the concentration of group II phospholipase A2 increased in the sera of patients after coronary artery bypass surgery. The concentration of Group I phospholipase A2 did not change. The catalytic activity of phospholipase A2 correlated significantly with group II but not with group I phospholipase A2 values. CONCLUSIONS: The increase in the catalytic activity of phospholipase A2 in serum after coronary artery bypass surgery is due to group II phospholipase A2. The present results suggest that group II phospholipase A2 is responsible for the physiologic and pathophysiologic effects of catalytically active phospholipase A2 after coronary artery bypass surgery.

Effects of dexmedetomidine on coronary hemodynamics and myocardial oxygen balance.

OBJECTIVE: alpha 2-adrenergic agonists decrease central sympathetic outflow and maintain normal transmural myocardial blood flow distribution, but intravenous bolus doses of these agents can also induce excessive coronary vasoconstriction and myocardial ischemia. The hypothesis of the present study was that a rapid intravenous bolus of dexmedetomidine, a specific alpha 2-adrenergic agonist, will cause coronary vasoconstriction and accompanying myocardial ischemia in young pigs. DESIGN: Prospective, controlled study on experimental animals. SETTING: Animal laboratory of a university cardiorespiratory research center. PARTICIPANTS: Twelve domestic 8-week-old open-chest pigs, anesthetized with high-dose fentanyl. Another six pigs served as controls. INTERVENTIONS: Sequential intravenous dexmedetomidine boluses of 3, 10, and 30 mg/kg were administered, and responses were measured during peak changes (2 minutes after injection) and during recovery after each dose. MEASUREMENTS AND MAIN RESULTS: Left anterior descending coronary artery blood flow, calculated regional coronary vascular resistance, myocardial extraction of oxygen and lactate, plasma catecholamine levels, and conventional central hemodynamic parameters were measured. The two higher doses of dexmedetomidine induced 21% and 29% immediate increases in left anterior descending coronary artery blood flow. At the same time mean systemic blood pressure and pulmonary capillary wedge pressure increased, and calculated regional coronary vascular resistance increased. Myocardial extraction of oxygen and lactate remained unchanged. CONCLUSIONS: Large intravenous doses of dexmedetomidine caused moderate regional coronary vasoconstriction without metabolic signs of myocardial ischemia in young domestic pigs at the same time as a marked vasoconstrictive response in the systemic circulation.

Proinflammatory mediator response in coronary bypass surgery using a centrifugal or a roller pump.

Major surgery, trauma, and infection induce a proinflammatory mediator response which, if excessive, may cause tissue injury. The response was measured during elective coronary bypass surgery when a centrifugal pump or a roller pump, differing in their basic working principles, was used for extracorporeal circulation (ECC). Eight patients were perfused with a centrifugal pump and eight patients with a roller pump during ECC. Plasma interleukin-1 beta (IL-1 beta), IL-2, IL-6, tumor necrosis factor alpha (TNF alpha), group II phospholipase A2, (PLA2), endotoxin, fibronectin and serum C-reactive protein (CRP) concentrations were measured. The operation increased plasma IL-6, group II PLA2, and serum CRP concentration and decreased plasma fibronectin concentrations. IL-1 beta and TNF alpha concentrations did not change. IL-2 occurred only occasionally, and endotoxin did not occur in any patient. No differences were seen between the group using a centrifugal pump and the group using the roller pump. Cardiac surgery with a perfusion time of less than two hours thus caused a proinflammatory mediator response which was similar whether a centrifugal or a roller pump was used for ECC.

Comparison of the effects of centrifugal versus roller pump on the immune response in open-heart surgery.

We compared the effects of a centrifugal pump with those of a roller pump on immune responses in 26 coronary artery bypass surgery patients during cardiopulmonary bypass (CPB). The patients were randomly allocated into a (Biomedicus) centrifugal pump group and a (Stöckert) twin roller pump group. Leucocyte and differential counts; percentages of lymphocyte subpopulations (CD3-, CD4-, CD8-, CD16-, CD20- and CD25-positive lymphocytes) and monocytes (CD14); phytohaemagglutinin-, concanavalin A-, and pokeweed mitogen-induced and unstimulated proliferation of separated lymphocytes; unstimulated and pokeweed mitogen-stimulated production of IgG, IgM, or IgA; and plasma fibronectin, C-reactive protein and serum albumin concentrations were measured preoperatively, immediately before CPB, immediately before aortic declamping and on the first postoperative morning. Significant changes were seen in these variables, but no differences occurred between the groups.

Serum phospholipases A2 after aortobifemoral reconstruction.

Phospholipase A2 has been implicated in the pathogenesis of local and distant tissue injury after ischaemia and reperfusion. A common operation inducing ischaemia and reperfusion is aortobifemoral reconstruction, during which the aorta is clamped and the blood supply via the inferior mesenteric artery and iliac arteries is interrupted. The purpose of the present work was to study the catalytic activity concentration of phospholipase A2 and the mass concentrations of group I and group II phospholipases A2 in the sera of patients undergoing aortobifemoral reconstruction. Both the catalytic activity concentration of phospholipase A2 and the mass concentrations of group I and group II phospholipases A2 increased in serum samples after the operation. The catalytic activity concentration of phospholipase A2 correlated well with group II phospholipase A2 mass values (r = 0.81, p < 0.001), whereas no correlation was found between the catalytic activity concentration of phospholipase A2 and group I phospholipase A2 mass values (r = 0.12, p = 0.54). The results emphasize the role of group II phospholipase A2 in tissue injury after ischaemia and reperfusion.

Leucocyte content in blood processed by autotransfusion devices during open-heart surgery.

Autologous red blood cells processed by autotransfusion devices have become increasingly common in major surgery. The finished product, however, often contains varying amounts of leucocytes. We compared leucocyte and their differential counts of blood processed by three autotransfusion devices (Haemonetics Cell Saver IV, Dideco Stat and Dideco Stat-P) during open-heart operations on 25 patients. In addition, a zymosan-induced, luminol-enhanced chemiluminescence method was used to evaluate the activity of neutrophils in prepared autologous blood. High leucocyte counts (3.6-10.9 x 10(9)l-1) were found in all saved red blood cell concentrates. The leucocyte counts of autologous blood produced by the Haemonetics device were lowest (P < 0.01) and about one third of the patients' haematocrit-corrected counts. The proportions of neutrophils were higher in salvaged blood than in the blood circulation before anaesthesia or before retransfusion (P < 0.01). However, no general activation of neutrophils was seen, but the increase in chemiluminescence activity of about 30% that was seen in four patients may suggest an increased risk of reperfusion injury in such patients after aortic declamping. In conclusion, all three autotransfusion devices left leucocytes in the processed red blood cell concentrates, although great differences occurred between the devices.

Effects of propofol and Intralipid on immune response and prostaglandin E2 production.

The present study evaluated the effects of propofol and its solvent Intralipid on the immune response and in vivo prostaglandin E2 production in patients during induction of anaesthesia and in healthy volunteers after Intralipid injection. Fifteen female patients (median age 48 years, ASA 1-2) scheduled for uterine dilatation and curettage were randomly assigned to two groups. In group 1 propofol (median dose 3.1 mg.kg-1) and in group 2 thiopentone (median dose 6.0 mg.kg-1) were injected intravenously over 60 s. Surgery was started after collection of the last blood sample. In the second part of this study, Intralipid 10% 0.3 ml.kg-1 was injected intravenously in eight healthy volunteers (four women and four men, median age 32 years) over 60 s. Plasma bicyclo-PGE2 concentrations increased during anaesthesia induction in both anaesthetic groups (p < 0.01). By contrast, no changes were seen in plasma bicyclo-PGE2 concentrations after Intralipid injection in volunteers. Lymphocyte proliferative responses to mitogens did not change during anaesthesia induction in patients. In volunteers, Intralipid injection caused a slight increase in T-cell percentages (p < 0.01) and unstimulated lymphocyte proliferative responses (p < 0.05), but it did not affect other lymphocyte subsets and immunoglobulin production. Intralipid and propofol were not found to be immunosuppressive at clinical doses used during anaesthesia induction.

Myocardial reperfusion after coronary bypass surgery. Suture of only distal or all anastomoses with the aorta cross-clamped?

Sixty patients undergoing elective coronary artery bypass grafting were randomly allocated into two groups, each of 30 patients and similar as regards age, sex, number of coronary artery bypasses and left ventricular ejection fraction. In group A the proximal anastomoses of vein grafts were sutured after aortic declamping during partial occlusion of the aorta, and in group B these anastomoses were done during aortic cross-clamping. The aortic cross-clamp time was significantly longer in group B than in group A (72 vs 57 min, p < 0.0001). Myocardial cooling and rewarming and the number of sustained or possible perioperative myocardial infarctions were equal in both groups. Central haemodynamics showed no intergroup difference, before or after induction of anaesthesia or at the end of surgery. Conduction disturbances were more common in group A than in group B (12 vs 3, p = 0.0246), and transient external pacing was more often required in group A (9 vs 2, p = 0.0534). Myocardial reperfusion via native coronary arteries and bypass grafts gives better protection against conduction disturbances than does reperfusion via only native arteries, despite longer aortic cross-clamping time.

Effects of cardiopulmonary bypass on lymphocytes and their subset counts with or without use of autotransfusion devices.

Lymphocytes and their subset counts were determined in 30 cardiac surgery patients during cardiopulmonary bypass (CPB) with or without use of an autotransfusion device. In the autotransfusion group, centrifuged and washed autologous red blood cells (median 400 mL [range 200-770 mL]) and in the control group corresponding amounts of homologous packed red blood cells (median 500 mL [range 250-750 mL]) were transfused after declamping the aorta. The percentages of T lymphocytes (CD3) and T cytotoxic cells (CD8) increased in both groups (CD3 up to 5%, P < 0.05 and CD8 up to 35%, P < 0.01), but the percentage of T helper cells (CD4) did not change. The ratio of CD4/CD8 cells decreased (up to 34%, P < 0.01). The percentage of naive resting T cells (CD45RA) increased slightly (up to 8%, P < 0.05) whereas the percentages of memory T cells (CD45RO), T cells with IL-2 receptor (CD25), and natural killer cells (CD16) remained unaltered. The percentage of HLA-DR positive lymphocytes increased during CPB (up to 18%, P < 0.05), but it was decreased thereafter (up to 16%, P < 0.05). The percentage of monocytes (CD14) decreased first during CPB in both groups (up to 32%, P < 0.01), but it was higher in the autotransfusion device group (decreased 29% from initial value) than in the control group (decreased 65% from initial value) at the end of CPB (P < 0.05). This study shows that extracorporeal circulation has an effect on lymphocytes and their subset counts. The changes were slightly immunosuppressive. By contrast, use of autotransfusion devices had only minor effects.

Blood transfusion with autologous and leukocyte-depleted or standard allogeneic red blood cells and the immune response to open heart surgery.

Allogeneic blood transfusions have been associated with impaired outcome in surgical patients. This effect may be mediated by leukocytes. Animal experiments have shown that at least some of the effect can be modified by removal of leukocytes from transfused blood. Therefore, we compared the effects of autologous + leukocyte-depleted against standard allogeneic red blood cell transfusion on postoperative immunosuppression in 24 men undergoing coronary artery bypass surgery. In the autologous + leukocyte-depleted red blood cell transfusion group, patients received 800 +/- 200 mL (mean +/- SD) autologous blood and 2.2 +/- 2.0 units (mean +/- SD) of leukocyte-depleted saline-adenine-glucose-mannitol (SAGM) red blood cells. In the standard red blood cell transfusion group, patients were transfused with 5.5 +/- 1.4 units (mean +/- SD) of SAGM red blood cells. Leukocyte and differential counts; percentages of lymphocyte subpopulations (CD3-, CD4-, CD8-, CD16-, CD20-, CD25-, and B5-positive lymphocytes) and monocytes (CD14); phytohemagglutinin-, concanavalin A-, and pokeweed mitogen-induced and unstimulated proliferation of separated lymphocytes; unstimulated and pokeweed mitogen-stimulated production of IgG, IgM, or IgA; and serum interleukin-6, interleukin-1 beta, and serum C-reactive protein concentrations were measured preoperatively and on postoperative Days 1, 7, and 21. Significant changes were seen in these variables, but there were no differences between the groups. Three of the 12 patients in the allogeneic leukocyte-containing red blood transfusion group became human lymphocyte antigen (HLA) alloimmunized. No infections or other complications occurred in any patients. We conclude that HLA alloimmunization was the only effect that could be modified by use of autologous blood.

Tonometric assessment of sigmoid perfusion during aortobifemoral reconstruction for arteriosclerosis.

OBJECTIVE: To assess the effect of inferior mesenteric artery reimplantation on perfusion of the mucosa of the sigmoid colon in patients undergoing aortobifemoral reconstruction for arteriosclerotic disease. DESIGN: Random control study. SETTING: University hospital. SUBJECTS: 8 Men and 2 women with peripheral vascular disease and angiographically patent superior and inferior mesenteric arteries. INTERVENTIONS: Patients were randomised to have the inferior mesenteric artery reimplanted in the Y-graft or not. Sigmoid perfusion was measured with a tonometer and expressed as the intramucosal pH (pHi) during operation (baseline) and for four days afterwards. MAIN OUTCOME MEASURES: Measurements of pHi, arterial blood gases, and acid base balance, and signs of ischaemia of the gut. RESULTS: In both groups the pHi was reduced after clamping the aorta, but returned to baseline on the first postoperative day. One patient had a cardiac arrest from which he was resuscitated and his pHi measurements were subsequently low. CONCLUSION: pHi does seem to reflect changes in the circulation of the sigmoid mucosa. Even if the inferior mesenteric artery is patent, reimplantation is only rarely indicated in patients undergoing aortobifemoral reconstruction.