Search PubMed⌕ Search

Biomedical subjects

H Bricard

Publications and source records attributed to H Bricard.

At least 37 records · Page 2Linked to original sources

[Indications and role of albumin for vascular loading in the operating room].

Prospective clinical studies on albumin and non human colloids, administered peroperatively, were analysed. Only those with a level of evidence I or II were considered. On the basis of the cost-effectiveness ratio, albumin should not be the first choice treatment for peroperative plasma volume expansion. Low molecular weight hydroxyethylstarch is as efficient for restoration and maintenance of volaemia and colloid osmotic pressure. Albumin is administered when other colloids are contra-indicated or when their upper limit of volume has been reached.

Albumins↗

Radioimmunoassay for plasma histamine: a study of false positive and false negative values.

In order to achieve a correct diagnosis of drug anaphylaxis using a radioimmunoassay devoid of interferences, we have studied factors leading to false positive or false negative values of plasma histamine. Different steps in sample collection were studied systematically in 30 normal volunteers. False positive values were found in haemolysed samples, with histamine concentrations being correlated with haemoglobin concentrations, and where plasma was aspirated from the white-cell layer. There was no significant increase when a tourniquet or vacuum tubes were used, or when blood tubes were left at 4 degrees C overnight. In 12 patients who experienced an anaphylactic reaction, histamine disappeared from blood 10 times more slowly than expected. False negative values were found in two pregnant women and one heparinized patient. Histamine was remarkably stable in vitro in blood or plasma samples, whereas it disappeared rapidly when plasma from a pregnant woman or a heparinized patient was added to the sample. We conclude that false positive and false negative values are rare when using this radioimmunoassay.

Adolescent↗

[Antibiotic prophylaxis in surgery of the esophagus].

Surgery of oesophagus carcinoma is a long and major procedure. Perioperative radiochemotherapy is often required. Therefore many factors favour the occurrence of local and general postoperative infection, justifying an antibiotic prophylaxis directed against oesophageal and gastric flora. In case of oesophageal stenosis, the oesophageal floral often switches to the fecal type. Antimicrobial agents diffuse to the surgical site and reach there high concentrations for the time of surgery. We recommend, just prior the induction of anaesthesia the intravenous administration of a single dose of a third generation cephalosporin (ceftriaxone 2 g) and nitroimidazole (ornidazole 1 g). The long half-life of these agents allows sufficient concentrations at surgical site to be obtained and the efficacy of this regimen has been demonstrated. Selective decontamination of the digestive tract with systemic antibiotherapy is another approach for the prevention of postoperative complications of surgery of oesophagus carcinoma.

Anti-Bacterial Agents↗

[Cardiac tamponade and central venous catheterization].

A 32-year-old female patient was operated on for a residual colonic stricture occurring after hemicolectomy. A right internal jugular central venous catheter was inserted during the anaesthetic for postoperative parenteral feeding. The anaesthetic combined both general and epidural anaesthesia, the latter being continued for postoperative analgesia (10 ml.h-1 of 0.125% bupivacaine). Two days later, the patient complained of sudden chest pain, with restlessness, tachycardia, cyanosis, resulting in ventricular tachycardia and cardiac arrest. When admitted to the surgical intensive care unit, the patient was in deep coma and had nonsustained ventricular tachycardia, a left haemopneumothorax and a pneumopericardium. The patient died before a definitive diagnosis was made. Postmortem examination revealed an ulcerated anterior pillar of the tricuspid valve, as well as a perforation of the right ventricle and a communication between the pericardium and the left pleural cavity. The diagnosis and treatment of this rare life-threatening complication may be very difficult. It prevention consists in using short catheters for internal jugular venous access, and checking the tip's position radiologically by opacifying the catheter.

Adult↗

[Efficacy and tolerance of Elohes 6% during peroperative normovolemic dilution].

This study assessed the cardiovascular stability of intraoperative normovolaemic haemodilution carried out with 6% Elohes during the exchange, the intraoperative, recovery and postoperative periods, as well as its effects on coagulation and renal function. Ten patients, ranked ASA 1, were included. Patients were premedicated with 100 mg of hydroxyzine, and anaesthesia was induced with 2 mg.kg-1 propofol, 3 micrograms.kg-1 fentanyl, and 0.5 mg.kg-1 atracurium. Maintenance was obtained with propofol, fentanyl and 50% nitrous oxide in oxygen. Haemodilution, carried out with a peripheral venous catheter, size 14 G, consisted in the removal of 15 ml.kg-1 of blood and its simultaneous replacement with Elohes 6%. Heart rate, systolic, diastolic and mean blood pressures were recorded before anaesthetic induction, every 5 min during the haemodilution, and thereafter during surgery, recovery and postoperative periods, up to the third postoperative day. Blood haemoglobin, fibrinogen, prothrombin, sodium, potassium, urea and creatinine concentrations, haematocrit, platelet count, and bleeding and activated cephalin times were assessed before and immediately after haemodilution, and on postoperative days 1 and 3. A mean of 1,295 +/- 68 ml of blood were removed during a 32 +/- 2 min period, and replaced by 1,315 +/- 64 ml of Elohes. Haematocrit decreased from 44 +/- 1.1% to 29.7 +/- 0.8%. There were no significant alterations in other parameters, except for an increase in heart rate at the time of extubation. Cardiovascular parameters, as well as the haemodilution, were stable up to the end of the study period. It is concluded that replacing blood with Elohes for intentional haemodilution affords convenient cardiovascular stability.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Early biological markers of anaphylactoid reactions occurring during anesthesia].

Three markers of in vivo histamine release, i.e. plasma histamine and tryptase, and urinary methylhistamine, were assessed using sensitive radioimmunoassays in 18 patients who had experienced an adverse reaction to an anaesthetic agent. Controls were obtained from 35 patients following a general anaesthetic, which included a muscle relaxant, and who remained free from any adverse reaction. A first blood sample was obtained from all 18 patients a mean 25 +/- 26 min after the reaction, and a second one in thirteen a mean 120 +/- 65 min after the reaction. Ten patients had had a life-threatening reaction. Plasma histamine levels were increased in all these cases, and tryptase concentrations in 9 out of 10. Urinary methylhistamine rarely reached pathological levels (4 out of 10). Skin tests were positive in the four tested patients. Plasma histamine concentration was still high in 8 cases thirty minutes after the reaction, and remained increased for more than 2 h in two patients. Among the other eight patients with a moderate reaction, 3 had high histamine levels, with normal or weakly increased tryptase concentrations, and normal urinary methylhistamine. Two of these patients had positive skin tests. There were no abnormal findings in any of the investigations carried out in the other five patients, except for a slightly positive skin test to atracurium in one patient. Plasma histamine had a higher sensitivity than tryptase levels. Methylhistamine concentrations were only rarely of interest. There were no false positives with the three investigated markers.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Early diagnosis of anaphylactic reactions to neuromuscular blocking drugs.

Neuromuscular blocking drugs (NMB) are involved in most of the anaphylactic reactions occurring during anaesthesia. Patients are evaluated usually 6 weeks after the reaction, by skin testing. In order to obtain an earlier diagnosis, we have measured plasma concentrations of histamine, tryptase and NMB-specific IgE antibodies in 14 patients after an anaphylactoid reaction. We have compared the results with those of skin tests and specific IgE obtained 8 weeks later. Good agreement was observed in all subjects between the results of skin tests and the values for histamine and tryptase, provided that both markers were measured simultaneously. Furthermore, there was no significant difference between the concentrations of NMB-specific IgE antibodies observed at the time of the reaction and 8 weeks later. Thus anaphylaxis to neuromuscular blocking drugs can be demonstrated at the time of the reaction by measuring plasma concentrations of histamine, tryptase and specific IgE. In the event of the patient's death, such measurements may be useful in identifying the likely cause.

Adolescent↗

[Perioperative transfusion strategy].

Tactics in blood transfusion have evolved considerably during the last ten years. Awareness of infectious risks and economic considerations have lead legislators to draw the guidelines for a safer transfusion. Their aim is to promote a better transfusion in smaller quantities at a lower risk. The goal of perioperative blood replacement is to maintain hemoglobin, blood volume and coagulation factors at an adequate level. This can be carried out by either homologous or autologous transfusion. Fresh frozen plasma transfusion is only required in severe bleeding where coagulation factors are depleted. The plasma substitutes must be used according to their intrinsic properties and their cost. The choice of an autologous technique depends on the type of surgical procedure, the expected blood loss and the economic resources available. Autologous blood transfusion may be optimized by the association of various techniques. This transfusion strategy must be elaborated by all the medical protagonists implicated in transfusion procedures.

Blood Transfusion↗

[Effectiveness of the Cell Saver and salvage from ultrafiltered extracorporeal circulation in heart surgery].

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)

Aged↗

Biochemical markers of anaphylactoid reactions to drugs. Comparison of plasma histamine and tryptase.

Adverse reactions to drugs require that their mechanisms be elucidated, particularly when anaphylaxis is suspected. Early diagnosis can be achieved by plasma histamine measurements. Unfortunately, the short plasma half-life of histamine and the difficulties in handling the sample usually preclude this measurement, although a sensitive radioimmunologic kit is routinely available. It has been recently suggested that mast cell tryptase, a component of the mast cell granules, could provide an alternative to histamine determination. We have measured plasma histamine and tryptase in 19 patients who developed possible anaphylactoid reactions to anesthetic or other drugs. Eight patients had increased values for both histamine and tryptase. In 4 a muscle relaxant drug was proved responsible for the reaction. Six patients had normal levels for both substances. In each case, the clinical signs of anaphylaxis were moderate. Two patients had normal histamine and high tryptase concentrations, due to late sampling (greater than 5 h). In 2 other patients, histamine was high, with normal tryptase: in 1, muscle relaxant allergy was further demonstrated. Tryptase half-life was equal to 90 min in 3 patients. At least 15 min was necessary to reach the peak level when the responsible drug was administered intravenously. The best time for measuring tryptase was 1-2 h after the reaction (not greater than 6 h), whereas for histamine it was 10 min to 1 h. We conclude that measurement of plasma tryptase along with measurement of plasma histamine may aid in diagnosis of anaphylaxis.

Adult↗

Intrapleural bupivacaine analgesia after thoraco-abdominal incision for oesophagectomy.

Intrapleural bupivacaine administration is said to produce good analgesia for the pain induced by a subcostal incision. However, reports of its efficacy after thoracotomy are conflicting. The goal of this study was to compare the analgesia produced by intrapleural administration of bupivacaine after oesophagectomy using a thoraco-abdominal incision with that obtained from intrapleural saline. After informed consent and institutional approval were obtained, 20 patients were randomly assigned to two groups of 10 patients each. Subjects received intrapleurally 10 ml of either 0.25% bupivacaine with 1:200,000 adrenaline or normal saline, every 8 h, beginning on the first post-operative day and lasting for 4 days. Pain was evaluated using a visual-analogue scale 2 h after the first daily treatment at rest and during physiotherapy. Pain scores were significantly lower in the bupivacaine group than in the saline group. Additionally, PaO2 was significantly higher in the bupivacaine group than in the saline group on Day 1 (P less than 0.05). The plasma bupivacaine concentration never reached the level of toxicity. Plasma bupivacaine concentrations on Day 1 after the first intrapleural bupivacaine injection were less than 350 ng ml-1; on Day 4 after the last injection they were less than 1300 ng ml-1. In conclusion, intrapleural administration of bupivacaine produces effective analgesia after oesophagectomy performed with a thoracoabdominal incision. The technique is easy to perform and is safe.

Abdomen↗

[Hereditary deficiency of antithrombin III, protein C and protein S. A study of 31 patients from 8 unrelated families].

The families of eight unrelated patients were studied with regard to a hereditary deficiency in antithrombin III (ATIII), protein C, or protein S. These deficiencies were recognized in the course of investigations for deep-vein thrombosis (DVT) in the eight patients. A group of 31 individuals (patients and family members), mostly less than 40-year-old was explored. Two cases of AT III deficiency were discovered, as well as 21 of protein C deficiency, and seven of protein S. Ten of the 30 have had recurrent venous thrombosis at the time of bedrest, trauma, surgery, pregnancy, postpartum or during oral contraceptive treatment. Spontaneous DVT occurred in three cases. Seventeen patients had remained asymptomatic till then. Such patients need antithrombotic treatment during surgery or pregnancy. Prophylactic treatment with enoxaparin in one patient (deficiency in protein C) during her second pregnancy is discussed. It seems that low molecular weight heparin may be a safe alternative to unfractionated heparin. Oral anticoagulants are efficient in preventing reoccurring venous thromboembolism in patients with AT III deficiency. The questions of whether oral anticoagulants should be continued in the long-term in patients with protein C or protein S deficiency who have had a DVT, and whether asymptomatic deficient patients should be given any antithrombotic treatment outside circumstances likely to induce a DVT, remain as yet unanswered.

Adolescent↗

[Anesthetics responsible for anaphylactic shock. A French multicenter study].

Combined allergological and anaesthetic consultations have been started in the last few years in eight French Teaching Hospitals so as to explore peranaesthetic anaphylactoid shocks. A survey was carried out in these centers in order to collect patients investigated with the same protocol, for the assessment of the incidence of anaphylaxis in France, as well as the involved drugs. Investigations were always carried out at least 6 to 8 weeks after the accident. The tests used to diagnose IgE-dependent anaphylaxis were skin tests (prick and intradermal tests, carried out in all eight centers), the radioimmunological assay of specific anti-quaternary ammonium IgE, together with an inhibition test with thiopentone and propofol (six centers), leukocyte histamine release (five centers) and human basophil degranulation tests (three centers) for those drugs for which no specific antibody assay exists. The collected data involved 1,240 patients, investigated within the last four years. Anaphylaxis was diagnosed in 821 patients (66.2%). Muscle relaxants were responsible in 668 cases (80% of cases of anaphylaxis). Suxamethonium was the main cause (54.3% of shocks due to muscle relaxants), followed by vecuronium (15.3%). General anaesthetics (hypnotics and benzodiazepines) were responsible for 9.2% of all cases of anaphylaxis opioids for 2.6%. There were only three cases of shock due to local anaesthetic agents. Latex and ethylene oxide are becoming increasingly involved. It would therefore seem mandatory to carry out after any anaphylactoid accident an assessment with sensitive and specific tests for anaphylaxis. Diagnosing anaphylaxis means that the involved drug should be used never again in that patient. Because muscle relaxants are by far the most involved drugs, anaesthetists should use them only when really required.

Analgesics, Opioid↗

Clinical pharmacokinetics after repeated intrapleural bupivacaine administration.

Patients (n = 14) who underwent thoracotomy during surgery of the oesophagus for cancer received an initial intrapleural dose of 10 ml bupivacaine hydrochloride 2.5 mg/ml followed by repeated administration every 8 hours from the first to the fourth postoperative day. The mean (+/- SD) peak plasma drug concentration (Cmax) [352 +/- 120 micrograms/L], time to peak (tmax) [0.83 +/- 0.51 h], and first-order absorption rate constant (ka) [5.46 +/- 4.95 h-1] after the twelfth dose were significantly different from the Cmax (206 +/- 81 micrograms/L), tmax (1.8 +/- 1.2h), and ka (1.8 +/- 1.47 h-1) determined after the first dose. Half-life (3.5 +/- 2.2h) and mean concentration (204 +/- 105 micrograms/L) were not significantly different on the fourth day from those on the first (4.1 +/- 2.6h and 142 +/- 71 micrograms/L, respectively). No sharp peak corresponding to systemic toxicity and no accumulation could be expected with these low doses, administered at short intervals and providing good pain relief in this surgical series.

Adult↗

[Differed autotransfusion in orthognathic surgery. Impact on the economics of blood products. Our experience of 40 cases].

Delayed autotransfusion has been recommended for orthognathic surgery. The authors review and discuss the advantages of this technique. Emphasis is placed on the preventive aspect as it relates to transfusion-associated viral contamination, as well as on the positive implications on health expenditures in the long run. This technique requires excellent intercollaboration on the part of the blood transfusion centers and should definitely be recommended in certain cases of planned surgery. Furthermore, combined with hemodilution methods, it constitutes a very effective means of struggle against edema.

Adolescent↗