Cardiac surgery with cardiopulmonary bypass in patients with type II heparin-induced thrombocytopenia.

BACKGROUND: The use of cardiopulmonary bypass (CPB) in patients with a history of type II heparin-induced thrombocytopenia (HIT) may be associated with complications related to their anticoagulation management. METHODS: Between January 1997 and December 1999, among 4,850 adults patients who underwent cardiac surgery in our institution, 10 patients presented with preoperative type II HIT. In 4 patients, anticoagulation during CPB was achieved with danaparoid sodium. In 6 other patients, heparin sodium was used after pretreatment with epoprostenol sodium. RESULTS: No significant change in platelet count occurred in any patient. No intraoperative thrombotic complication was encountered. Total postoperative chest drainage ranged from 250 to 1,100 ml in patients pretreated with epoprostenol and 1,700 to 2,470 ml in patients who received danaparoid sodium during CPB (p < 0.05, Mann-Whitney U test). CONCLUSIONS: During CPB, inhibition of platelet aggregation by prostacyclin may be a safe anticoagulation approach in patients with type II HIT.

[Surgery of active-phase infective endocarditis: report of 13 cases]. / Chirurgie de l'endocardite infectieuse à la phase active: à propos de 13 cas.

OBJECTIVE: Infective endocarditis is always a disease at the present time. In this work we report our initial experience of infective endocarditis surgical treatment during the acute phase. METHODS AND RESULTS: Between September 1993 and December 1997, 13 patients underwent valvular surgery for native infective endocarditis. Mean age was 31 +/- 11 years (range: 9 to 42 years); 92.3% of the patients presented with pre-existing rheumatical valvular lesion. Surgical indication was the occurrence of heart failure in all these patients. Surgery consisted on aortic valvular replacement in four patients, mitral and aortic valvular replacement in nine patients. Tricuspid valvuloplasty was required in two patients. Early mortality was 15% (two patients). A third patient developed cardiac failure and died three years postoperatively. CONCLUSION: This work emphasises the interest of the surgical treatment in the active phase of the infective endocarditis.

Safety of oral nicorandil before coronary artery bypass graft surgery.

Nicorandil is a K(ATP) channel opener used to treat angina. It is cardioprotective and a vasodilator. We conducted a prospective, randomized, double-blind, placebo-controlled study to assess oral nicorandil in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). Twenty-two patients received nicorandil (10 mg twice a day) and 23 patients received placebo. Haemodynamic data were recorded before induction of anaesthesia (T0), 5 and 20 min after starting mechanical ventilation (T1, T2), before aortic cannulation (T3), after 30 min of CPB (T4), 10 min after CPB (T5) and after 3, 8 and 18 h in the intensive care unit (T6, T7, T8). Serum proteins (creatine kinase metabolite and cardiac troponin I) were measured before and 8 and 18 h after surgery. Haemodynamic values did not differ between the two groups. There was no tachycardia during the study, no significant difference in hypotensive episodes, ST segment changes and no changes in cardiac enzymes. Myocardial infarction after surgery was similar in the two groups. Vasoactive therapy was similar in the two groups. Nicorandil can be continued safely up to premedication without deleterious haemodynamic consequences, but a myocardial protective effect of nicorandil in CABG surgery was not found.

Usefulness of procalcitonin for diagnosis of infection in cardiac surgical patients.

OBJECTIVE: To determine the value of procalcitonin (PCT) as a marker of postoperative infection after cardiac surgery. DESIGN: A prospective single institution three phase study. SETTING: University cardiac surgical intensive care unit (31 beds). PATIENTS: Phase 1: To determine the normal perioperative kinetics of PCT, 20 consecutive patients undergoing elective cardiac surgery with cardiopulmonary bypass were included. Phase 2: To determine whether PCT may be useful for diagnosis of postoperative infection, 97 consecutive patients with suspected infection were included. Phase 3: To determine the ability of PCT to differentiate patients with septic shock from those with cardiogenic shock, 26 patients with postoperative circulatory failure were compared. MEASUREMENTS AND MAIN RESULTS: Phase 1: Serum samples were drawn for PCT determination after induction of anesthesia (baseline), at the end of surgery, and daily until postoperative day (POD) 8. Baseline serum PCT concentration was 0.17 +/- 0.08 ng/mL (mean +/- SD). Serum PCT increased after cardiac surgery with a peak on POD 1 (1.08 +/- 1.36). Serum PCT returned to normal range on POD 3 and remained stable thereafter. Phase 2: In patients with suspected infection, serum PCT was measured at the same time of C-reactive protein (CRP) and bacteriologic samples. Among the 97 included patients, 54 were infected with pneumonia (n = 17), bacteremia (n = 16), mediastinitis (n = 9), or septic shock (n = 12). In the 43 remaining patients, infection was excluded by microbiological examinations. In noninfected patients, serum PCT concentration was 0.41 +/- 0.36 ng/mL (range, 0.08-1.67 ng/mL). Serum PCT concentration was markedly higher in patients with septic shock (96.98 +/- 119.61 ng/mL). Moderate increase in serum PCT concentration occurred during pneumonia (4.85 +/-3.31 ng/mL) and bacteremia (3.57 +/- 2.98 ng/mL). Serum PCT concentration remained low during mediastinitis (0.80 +/- 0.58 ng/mL). Five patients with mediastinitis, two patients with bacteremia, and one patient with pneumonia had serum PCT concentrations of <1 ng/mL. These eight patients were administered antibiotics previously and serum PCT was measured during a therapeutic antibiotic window. For prediction of infection by PCT, the best cutoff value was 1 ng/mL, with sensitivity 85%, specificity 95%, positive predictive value 96%, and negative predictive value 84%. Serum CRP was high in all patients without intergroup difference. For prediction of infection by CRP, a value of 50 mg/L was sensitive (84%) but poorly specific (40%). Comparing the area under the receiver operating characteristic curves, PCT was better than CRP for diagnosis of postoperative sepsis (0.82 for PCT vs. 0.68 for CRP). Phase 3: Serum PCT concentration was significantly higher in patients with septic shock than in those with cardiogenic shock (96.98 +/- 119.61 ng/mL vs. 11.30 +/- 12.3 ng/mL). For discrimination between septic and cardiogenic shock, the best cutoff value was 10 ng/mL, with sensitivity of 100% and specificity of 62%. CONCLUSION: Cardiac surgery with cardiopulmonary bypass influences serum PCT concentration with a peak on POD 1. In the presence of fever, PCT is a reliable marker for diagnosis of infection after cardiac surgery, except in patients who previously received antibiotics. PCT was more relevant than CRP for diagnosis of postoperative infection. During a postoperative circulatory failure, a serum PCT concentration >10 ng/mL is highly indicative of a septic shock.

[Perioperative beta-blockers. Part one: fundamentals]. / Intérêt des bêta-bloquants en médecine périopératoire. Première partie: notions fondamentales.

PURPOSE: To review the pharmacologic and pathophysiologic information necessary to prescribe beta-blockers (BB) in perioperative medicine. DATA SOURCE: Manual retrieval and electronic research of the literature using MEDLINE (key-words: anesthesia and beta- blocker; surgery and beta-blocker). DATA SYNTHESIS: Cardioselective BB inhibit preferentially beta-1 receptors, inducing a decrease in heart rate and cardiac inotropism leading to reduction of oxygen myocardial consumption. Non-cardioselective BB inhibit also beta-2 receptors, increasing bronchial and peripheral vascular resistances and uterine contractions. However, some BB are also vasodilators (carvedilol, celiprolol, labetalol). Contraindications to BB result logically from their pharmacological effects. Treatment with BB increases membrane beta-receptor density; this explains sympathetic overactivity observed during weaning of treatment. Since the discovery of propranolol in 1964, the use of BB has been controversial in anesthesia. Formerly, the adverse effects of partial sympatholysis during anesthesia and surgery were feared. However, since 1973, experimental and clinical data have suggested a protective hemodynamic effect. CONCLUSION: Continued administration of BB up to the time of anesthesia has been encouraged except in patients with signs of intolerance such as hypotension or excessive bradycardia.

[Perioperative beta-blockers. Part two: therapeutic indications]. / Intérêt des bêta-bloquants en médecine périopératoire. Deuxième partie: indications thérapeutiques.

PURPOSE: To review the pharmacologic and pathophysiologic information necessary to prescribe beta-blockers (BB) in perioperative medicine. DATA SOURCE: Manual retrieval and electronic research of the literature using MEDLINE (key-words: anesthesia and beta- blocker; surgery and beta-blocker). DATA SYNTHESIS: In non cardiac surgery, the beneficial effects of BB have been demonstrated in hypertensive patients since 1979. In 1996, the beneficial effects of atenolol in patients with coronary artery disease (reduction of postoperative myocardial ischemia and overall reduction in two-year mortality) were demonstrated. In coronary surgery, the interest of preoperative BB treatment has been shown since 1983. Administration of BB has been shown to be beneficial in acute myocardial infarction or chronic cardiac failure (except in NYHA class IV patients). CONCLUSION: BB have been shown to exert a beneficial effect on postoperative outcomes in patients with cardiovascular disease or risk factors, and their more widespread use in perioperative medicine is encouraged.

Relative importance of flow versus pressure in splanchnic perfusion during cardiopulmonary bypass in rabbits.

BACKGROUND: Decreased gastrointestinal perfusion has been reported during cardiopulmonary bypass (CPB). Conflicting results have been published concerning thresholds of pressure and flow to avoid splanchnic ischemia during CPB. This study compared splanchnic perfusion during independent and randomized variations of CPB pump flow or arterial pressure. METHODS: Ten rabbits were studied during mild hypothermic (36 degrees C) nonpulsatile CPB using neonatal oxygenators. Simultaneous measurements of tissue blood flow in four different splanchnic areas (gastric, jejunum, ileum, and liver) were performed by laser Doppler flowmetry (LDF) before CPB (T0) and during a 4-step factorial experimental block design. Pressure and flow were alternatively high or low in random order. RESULTS: Laser Doppler flowmetry was significantly lower than pre-CPB value but was better preserved (analysis of covariance) in all organs, except liver, when CPB flow was high, whatever the pressure. Splanchnic LDF values in the low- versus high-flow groups expressed as perfusion unit were (mean +/- SD): stomach, 94+/-66 versus 137+/-75; jejunum, 118+/-78 versus 172+/-75; ileum, 95+/-72 versus 146+/-83; and liver, 79+/-72 versus 108+/-118. No significant difference of LDF was observed between the high- and low-pressure groups, whatever the flow, except for liver: stomach, 115+/-64 versus 117+/-83; jejunum, 141+/-80 versus 148+/-83; ileum, 127+/-87 versus 114+/-76; liver, 114+/-88 versus 73+/-70. CONCLUSION: Prevention of splanchnic ischemia during CPB should focus on preservation of high CPB blood flow rather than on high pressure.

[Minimally invasive cardiac surgery: surgical techniques and anesthetic problems]. / Chirurgie cardiaque mini-invasive: techniques chirurgicales et particularités anesthésiques.

OBJECTIVE: To review current data on minimally invasive cardiac surgery. DATA SOURCES: Search through the Medline data base of French or English articles. DATA EXTRACTION: The articles were analysed to make a synthesis of the various techniques with their main indications and contra-indications. DATA SYNTHESIS: Minimally invasive cardiac surgery includes various surgical procedures. The usual techniques are described, their major benefits and drawbacks are discussed. The main goals of anaesthetic management are preservation of ventricular function and systemic perfusion, detection and treatment of myocardial ischaemia, prevention of hypothermia in case of coronary artery bypass grafting on the beating heart via sternotomy, intermittent selective ventilation of the collapsed lung using CPAP in case of limited thoracotomy. Expertise in transoesophageal echocardiography is essential for insertion and checking the accurate positioning of the various catheters of the endovascular CPB Heartport system (pulmonary vent, endosinus catheter, venous cannula, endoaortic clamp) allowing coronary artery bypass grafting and mitral valve surgery through limited thoracotomy and finally, detection of retained intracardiac air and assessment of complete clearing of cardiac cavities after mitral valve surgery through limited thoracotomy and aortic valve surgery via ministernotomy. Short-acting anaesthetic agents allow rapid recovery from anaesthesia, early extubation and discharge to the surgical ward within 24 h, whereas overall time spent in the operating room is often longer than with conventional cardiac surgery.

Effects of dopexamine on blood flow in multiple splanchnic sites measured by laser Doppler velocimetry in rabbits undergoing cardiopulmonary bypass.

Decreased gut perfusion has been reported during cardiopulmonary bypass (CPB). Studies of treatments to avoid splanchnic ischaemia during CPB have given conflicting results. We studied 12 rabbits during mild hypothermic non-pulsatile CPB. Tissue blood flow in three different splanchnic areas (gastric, jejunum and ileum) was measured by laser Doppler velocimetry (LDV) before CPB (T0), after steady state (T1), after administration of dopexamine 2 micrograms kg-1 min-1 (T2) and 4 micrograms kg-1 min-1 (T3), and after return to baseline (T4). Splanchnic blood flow decreased during CPB. Dopexamine increased significantly jejunum LDV (100% at T1 to mean 271 (SD 210)% at T2) and ileum LDV (100% at T1 to 187 (112)% at T2). Gastric LDV was not altered by infusion of dopexamine during CPB. This could partly explain the conflicting results on the value of gastric tonometry as an index of splanchnic injury.

[Severe digestive complications after heart surgery using extracorporeal circulation]. / Complications digestives sévères après chirurgie cardiaque sous circulation extracorporelle.

PURPOSE: To determine the incidence, circumstances of occurrence and evolution of gastrointestinal complications after cardiac surgery with extracorporeal circulation (ECC). METHODS: Retrospective chart study of gastrointestinal complications in 6.281 patients undergoing ECC between january 1994 and December 1997. RESULTS: Sixty patients developed 68 gastrointestinal complications (1%). Complications included: upper gastrointestinal bleeding (n = 23), intestinal ischemia (n = 19), cholecystitis (n = 7), pancreatitis (n = 6), and paralytic ileus (n = 16). The incidence of these complications was low after coronary artery (0.4%) or valvular surgery (0.8%) and high after cardiac transplantation (6%) and after surgery for acute aortic dissection (9%). Compared with a control population, patients with gastrointestinal complication had a higher Parsonnet score (29 +/- 15 vs 13 +/- 12 points; P = 0.002), were more frequently operated upon as an emergency (40/60, 66% vs 1120/6221, 18%; P = 0.01), underwent ECC of longer duration (114 +/- 66 vs 74 +/- 42 min; P = 0.01), and presented more frequently with low cardiac output after surgery (45/60, 75% vs 435/6221, 7%; P = 0.001). The mortality rate after gastrointestinal complications was 52%. The major factor associated with mortality was the occurrence of sepsis (OR = 38.7). Other factors were: renal failure (OR = 7.9), age > 75 yr (OR = 3.5), mechanical ventilation for more than seven days (OR = 2.7), associated cerebral damage (OR = 3.9). CONCLUSION: Gastrointestinal complications after ECC occur in high risk surgical patients. These complications are frequently associated with other complications leading to a high mortality rate.

Effect of cardiopulmonary bypass on serum procalcitonin and C-reactive protein concentrations.

We have measured serum procalcitonin (PCT) concentrations after cardiac surgery in 36 patients allocated to one of three groups: group 1, coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) (n = 12); group 2, CABG without CPB (n = 12); and group 3, valvular surgery with CPB (n = 12). Serum PCT and C-reactive protein (CRP) concentrations were measured before operation, at the end of surgery and daily until postoperative day 8. Serum PCT concentrations increased, irrespective of the type of cardiac surgery, with maximum concentrations on day 1: mean 1.3 (SD 1.8), 1.1 (1.2) and 1.4 (1.2) ng ml-1 in groups 1, 2 and 3, respectively (ns). Serum PCT concentrations remained less than 5 ng ml-1 in all patients. Concentrations returned to normal by day 5 in all groups. To determine the effect of the systemic inflammatory response (SIRS) on serum PCT concentrations, patients were divided post hoc, without considering the type of cardiac surgery, into patients with SIRS (n = 19) and those without SIRS (n = 17). The increase in serum PCT was significantly greater in SIRS (peak PCT 1.79 (1.64) ng ml-1 vs 0.34 (0.32) ng ml-1 in patients without SIRS) (P = 0.005). Samples for PCT and CRP measurements were obtained from 10 other patients with postoperative complications (circulatory failure n = 7; active endocarditis n = 2; septic shock n = 1). In these patients, serum PCT concentrations ranged from 6.2 to 230 ng ml-1. Serum CRP concentrations increased in all patients, with no differences between groups. The postoperative increase in CRP lasted longer than that of PCT. We conclude that SIRS induced by cardiac surgery, with and without CPB, influenced serum PCT concentrations with a moderate and transient postoperative peak on the first day after operation. A postoperative serum PCT concentration of more than 5 ng ml-1 is highly suggestive of a postoperative complication.

Effects of intraoperative glucose administration on circulating metabolites and nitrogen balance during prolonged surgery.

STUDY OBJECTIVES: To compare the effects of intraoperative administration of 2.5% glucose or Ringer's solution on metabolism during prolonged surgery. DESIGN: Prospective, randomized study. SETTING: Teaching hospital. PATIENTS: 20 ASA physical status I and II adults patients scheduled for thoracic or abdominal surgery lasting at least 3 hours. INTERVENTIONS: Patients received Ringer's solution (Group R) or 2.5% glucose solution (Group G) 10 ml.kg-1.h-1 during surgery and 2 ml.kg-1.h-1 during the first two postoperative hours (Ringer's or glucose), then 40 ml.kg-1.day-1 of 5% intravenous (i.v.) glucose postoperatively. MEASUREMENTS AND MAIN RESULTS: Plasma glucose, free fatty acids, ketone bodies, lactate, insulin, glucagon, cortisol, and growth hormone concentrations were determined after an overnight fast (T0), on induction of anesthesia (T1), at the end of surgery (T2), 2 hours thereafter (T3), and on the following morning (T4). Capillary blood glucose was determined every 30 minutes from T1 to T2. Urinary nitrogen and 3-methylhistidine were measured every day for 5 days. There were no differences between groups in demographic data, anesthesia, or surgical procedures. All data were comparable at baseline and on the following morning. In Group R, no patient experienced hypoglycemia, but plasma fatty acids and ketone bodies increased during surgery. In Group G, glycemia rose to very high levels, with a significant increase in insulin during surgery. Other hormones were the same within the two groups. Urinary nitrogen and 3-methylhistidine were similar in both groups. CONCLUSION: The absence of glucose infusion in prolonged surgery did not cause hypoglycemia, and no increase in protein catabolism was observed.

Glucose versus lactated Ringer's solution during pediatric cardiac surgery.

OBJECTIVE: Whether intraoperative fluid infusion should contain glucose during pediatric cardiac surgery remains controversial. This study was performed to compare the effects of glucose and glucose-free solutions on blood glucose and blood insulin levels during total repair of congenital heart diseases. DESIGN: Prospective randomized and blinded study. SETTING: Cardiovascular university center. PARTICIPANTS: Forty nondiabetic children, weight ranging from 4 to 10 kg, scheduled for cardiac surgical procedures requiring cardiopulmonary bypass (CPB) without total circulatory arrest. INTERVENTIONS: Group R (n = 20) was administered lactated Ringer's solution intraoperatively, and group G (n = 20) received 5% glucose. Fluids were infused at a rate of 3 mL/kg/h in the two groups from the induction of anesthesia to the end of the surgical procedure. Blood glucose and insulin were sampled before infusion (Tzero), before CPB (T1), 10 minutes after initiation of CPB (T2), 10 minutes after initiation of rewarming (T2), and at the end of the procedures (T4). Postoperatively, blood glucose was measured at the first, 12th, and 24th hours. MEASUREMENTS AND RESULTS: During the prabypass period, three children in group R had severe hypoglycemia (blood glucose < 40 mg/dL). After initiation of CPB, blood glucose increased in both groups, with a small difference at the end of the procedure. No infants in the two groups had blood glucose higher than 239 mg/dL. CONCLUSIONS: Glucose withdrawal during pediatric cardiac surgery induces threatening hypoglycemia during the prabypass period, and moderate intraoperative glucose administration (2.5 mg/kg/min) is not responsible for major hyperglycemia.

[Non-steroidal anti-inflammatory agent and angiotensin converting enzyme inhibitor: a dangerous combination during postoperative period]. / Anti-inflammatoire non stéroïdien et inhibiteur de l'enzyme de conversion: association dangereuse en période postopératoire.

A 72-year-old man experienced a postoperative acute renal failure (ARF) from a nonsteroidal anti-inflammatory drug (NSAID) and an angiotensin converting enzyme inhibitor (ACEI) intake and promoted by an unrecognized myeloma, peroperative hypotension and hormonal response to surgical stress. This drug combination can result in ARF through a fall of glomerular filtration by combined renal blood flow changes: NSAID inhibit vasodilation by renal prostaglandins, and the vasoconstrictor effect on the efferent arteriole is inhibited by the ACEI. Nephrotoxicity during the simultaneous use of ACEI and NSAID is increased by other risk factors of renal insufficiency such as ageing, preexisting renal disease and hypovolaemia. In these cases, a preventive therapy should be considered.