[Cholelithiasis in heart transplant patients]. / Lithiase biliaire chez le transplanté cardiaque.

UNLABELLED: The incidence of cholelithiasis is increased in heart transplant recipients. STUDY AIM: The aim of this retrospective study was to report a series of 27 heart transplant recipients operated for cholelithiasis and to assess the indications and safety of cholecystectomy in this population. PATIENTS AND METHODS: Over a 9-year period, from January 1991 to December 1999, 27 heart transplant recipients (21 men and 6 women; mean age: 54.6 years, mainly transplanted for ischemic or dilated cardiomyopathy) underwent cholecystectomy. All patients received immunosuppressive therapy with a combination of corticosteroids and cyclosporin and 10 also received azathioprine. Five patients admitted urgently with calculous acute cholecystitis and one patient with previous gastrectomy underwent laparotomy, while the other 21 patients were operated by laparoscopy. RESULTS: There were no postoperative deaths. In patients operated by laparoscopy, there was no conversion to laparotomy and oral immunosuppressive drugs were continued without interruption. There was one postoperative hemoperitoneum related to liver biopsy performed concomitantly. In patients operated by laparotomy, intravenous cyclosporin was necessary until return to bowel function and the only complication was a wound abscess. Mean length of hospital stay was 3.1 days after laparoscopy and 8.8 days after laparotomy. CONCLUSION: Systematic ultrasound screening of cholelithiasis after heart transplantation is necessary because cholelithiasis carries a risk of septic complications in these patients. Laparoscopic cholecystectomy, associated with a low morbidity, is justified even in asymptomatic cases. In patients with acute cholecystitis, "open" cholecystectomy must be preferred in order to minimize the risk of biliary complications which would be very serious in these immunosuppressed patients.

[Rhabdomyolysis after ORL surgery in prolonged lateral position]. / Rhabdomyolyse au décours d'une chirurgie ORL en décubitus latéral prolongé.

Two cases are reported of upper limb rhabdomyolysis occurring after prolonged ENT cancer surgery, the patient being part of the time in the right lateral position, with the left forearm outstretched. Surgery consisted of a vertical hemilaryngectomy with immediate parascapular free graft reconstruction in a 48-year-old man (10 h of surgery, with 6 h in a lateral position) and the surgical removal of a neoplasm involving the mouth floor and larynx in a 62-year-old man including parascapsular free graft reconstruction (10 h of surgery, with 7 h in a lateral position). In the early postoperative period, the patients complained of severe pain in the left forearm. There was a tense painful swelling of the forearm, combined with an increase in creatinine kinase plasma concentration, and myoglobinaemia. The mechanism involved was most likely a compression of the forearm muscles, together with prolonged surgery and the patient position. The part played by the state of the patients is discussed. Diagnosis must be made as soon as possible, as the only efficient treatment consists of an early fasciotomy together with the administration of alkali to avoid renal failure.

[Development of antifactor VIII circulating anticoagulant after surgery of the biliary tract]. / Apparition d'un anticoagulant circulant antifacteur VIII après chirurgie de la voie biliare.

In a 25-year-old woman, admitted with a haemorrhagic syndrome following biliary surgery, an inhibitor of factor VIII was detected. As bleeding was major, she was re-operated on under perioperative administration of the anti-inhibitory coagulant complex Autoplex-T, associated with polyvalent i.v. immunoglobulins. The other therapeutic agents are also considered and their indications discussed, after a review of the circumstances of the diagnosis of this disease.

[Pneumatic tourniquet paralysis. A differential diagnosis after loco-regional anesthesia of the upper limb]. / Le syndrome paralytique du garrot. Un diagnostic différentiel après anesthésie locorégionale du membre supérieur.

A case is reported of a severe neurological deficit after hand surgical using pneumatic tourniquet. The 51 year old ASA I patient underwent an axillary block for hand surgery using 50 ml of mepivacaïne 1%. The tourniquet was remained at 300 mmHg for only 45 min. The following day, the patient's arm remained lumb. Electrophysiologic tests showed a severe conduction block of sensory and motor fibers, well localized to the presume lower margin of the tourniquet. As there was no improvement, epineurotomy was carried out on day 60, to liberate the median nerve which was severely compressed in the canal brachial. The patient then started to improve slowly. But many safety factors can decrease the rate complications: the accuracy and integrity of the pressure-monitoring must be verified, a tourniquet pressure above 300-500 mmHg would rarely be required in normotensive patient with compliant vessel, a pressure of 200 mmHg will almost all cases provide a bloodless field, tourniquet must be applied on diaphysis and not on bony relief.

Comparison of relaxation responses to multiple vasodilators in TxA(2)-analog and endothelin-1-precontracted pulmonary arteries.

BACKGROUND: Peri-operative pulmonary hypertension can lead to right ventricular dysfunction and to an increase in morbidity and mortality. Altered function of the pulmonary vascular endothelium and vasoconstriction play a crucial role in the development of elevated pulmonary vascular resistance. Because pulmonary artery vasoreactivity is dependent on many factors including the constricting agent that precipitated the event therefore the aim of the current study was to investigate the effectiveness of different classes of vasodilator agents to reverse endothelin-1 (ET-1) or thromboxane A(2) (TxA(2))-induced vasoconstriction in porcine pulmonary artery (PA) in vitro. METHODS: Relaxation responses to vasodilatory drugs were studied in PA precontracted with ET-1 (1 x 10(-8) M) or TxA(2) analog (U46619, 1 x 10(-8) M). All vasodilating drugs were added in a cumulative fashion and isometric tension measurements were obtained using an organ chamber technique. RESULTS: In both groups relaxation responses to the vasodilators were dose dependent. When ET-1 was used as a constrictor nitroglycerin and milrinone caused nearly complete (80-100%) relaxation, whereas other agents were of limited effectiveness (40-50%). On the other hand, in the vessels constricted with U46619, olprinone, indomethacin, prostaglandin E(1) (PGE(1)), nitroglycerin, milrinone and clevidipine induced complete (90-110%) vasodilatation but brain natriuretic peptide (BNP), L-arginine, and isoproterenol relaxed the vessels maximally by 45-60%. CONCLUSIONS: Nitroglycerin and milrinone are very effective in reversing ET-1 and U46619-induced pulmonary vasoconstriction in vitro. The effectiveness of other drugs studied was dependent on the type of constrictor used. BNP, L-arginine and isoproterenol were shown to have minimal vasodilatory effects in porcine PA.

Prediction of difficult mask ventilation.

BACKGROUND: Maintenance of airway patency and oxygenation are the main objectives of face-mask ventilation. Because the incidence of difficult mask ventilation (DMV) and the factors associated with it are not well known, we undertook this prospective study. METHODS: Difficult mask ventilation was defined as the inability of an unassisted anesthesiologist to maintain the measured oxygen saturation as measured by pulse oximetry > 92% or to prevent or reverse signs of inadequate ventilation during positive-pressure mask ventilation under general anesthesia. A univariate analysis was performed to identify potential factors predicting DMV, followed by a multivariate analysis, and odds ratio and 95% confidence interval were calculated. RESULTS: A total of 1,502 patients were prospectively included. DMV was reported in 75 patients (5%; 95% confidence interval, 3.9-6.1%), with one case of impossible ventilation. DMV was anticipated by the anesthesiologist in only 13 patients (17% of the DMV cases). Body mass index, age, macroglossia, beard, lack of teeth, history of snoring, increased Mallampati grade, and lower thyromental distance were identified in the univariate analysis as potential DMV risk factors. Using a multivariate analysis, five criteria were recognized as independent factors for a DMV (age older than 55 yr, body mass index > 26 kg/m2, beard, lack of teeth, history of snoring), the presence of two indicating high likelihood of DMV (sensitivity, 0.72; specificity, 0.73). CONCLUSION: In a general adult population, DMV was reported in 5% of the patients. A simple DMV risk score was established. Being able to more accurately predict DMV may improve the safety of airway management.

The vasodilator effects of clevidipine on human internal mammary artery.

UNLABELLED: Endothelial dysfunction and platelet activation with thromboxane release may contribute to spasm or alterations in internal mammary artery (IMA) graft flow during coronary artery surgery. Clevidipine, an ultrashort-acting dihydropyridine calcium channel blocker, is undergoing clinical development, but there are little data regarding its effects on human vasculature. We investigated the effects of clevidipine on human IMA obtained during surgery. After precontracting IMA segments with an analog of thromboxane (U46619, 10(-8) mol/L), acetylcholine and nitroglycerin were added cumulatively to examine endothelial function. Concentration-response curves to clevidipine were cumulatively obtained during submaximal contraction to the U46619 (10(-8) mol/L) in rings with and without endothelium. In the IMA samples with endothelium, acetylcholine did not completely reverse the U46619-mediated contraction, which implies impaired endothelial function (40% +/- 6% maximal response). Both clevidipine and nitroglycerin completely reversed U46619-induced contraction (clevidipine (50% effective concentration [EC50] = 3.88 +/- 0.84 x 10(-6) mol/L, nitroglycerin EC50 = 4.84 +/- 2.76 x 10(-8) mol/L). The responses to clevidipine were similar in preparations with or without intact endothelium. Clevidipine is an endothelium-independent arterial vasodilator that offers a potential therapeutic option in the treatment of perioperative arterial graft vasospasm and/or hypertension. IMPLICATIONS: Clevidipine is a new ultrashort-acting dihydropyridine calcium antagonist. In human internal mammary arteries precontracted with a thromboxane A2 analog, clevidipine was an effective vasodilator on vessel segments in the presence and in the absence of endothelium.

A comparative evaluation of the effects of multiple vasodilators on human internal mammary artery.

BACKGROUND: Vasospasm of arterial grafts represents an unpredictable complication of coronary artery surgery and may compromise myocardial revascularization, and treatment is based on empirical therapy with nitroglycerin. Because of the potential for tolerance to nitroglycerin to occur, the authors studied different vasodilators acting through separate pathways on segments of human internal mammary artery. METHODS: Isolated vascular rings were precontracted with norepinephrine (1 microM), KCl, or the thromboxane A2 analogue (U46619, 10 nm). Nitroglycerin (a nitrovasodilator), milrinone (a type III phosphodiesterase inhibitor), papaverine (a phosphodiesterase inhibitor), prostaglandin E1, and isradipine (a dihydropyridine calcium channel blocker) were added in a cumulative fashion. RESULTS: The analysis of the concentration-response curves showed that vasodilators induced 90-100% relaxation of the constricted segments with norepinephrine or the thromboxane A2 analogue, except prostaglandin E1, which produced 73% relaxation at maximal concentrations. The effective concentrations of vasodilator agent that caused 50% relaxation for nitroglycerin and milrinone were within the range of the reported therapeutic concentrations in plasma. Isradipine was also effective at reversing receptor-mediated contraction (maximal relaxation=100% in internal mammary artery contracted with norepinephrine; maximal relaxation=0% in internal mammary artery contracted with the thromboxane A2 analogue). CONCLUSIONS: Vasodilator drugs acting through multiple pathways are effective at reversing in vitro vasoconstriction.

Hemostatic changes in patients receiving hydroxyethyl starch: the influence of ABO blood group.

Hydroxyethyl starches (HES) interfere with coagulation because of their molecular structure and the amount infused during surgery. Coagulation defects include platelet dysfunction and a decrease of the VIII/von Willebrand factor complex (VIII/vWF). We examined the effects of 6% HES 200/0.6 on hemostasis by using an in vitro platelet function analyzer, the usual coagulation tests, the VIII/vWF complex assessment, and TEG analysis in patients undergoing abdominal surgery. The influence of the blood group was investigated. HES infusion induced primary hemostasis alterations, assessed by a prolonged platelet function analyzer closure time in the presence of epinephrine and adenosine diphosphate, which was not correlated with the platelet count. The decrease in VIII/vWF complex was proportional to the volume of infused HES (20 and 30 mL/kg) and was more pronounced in patients of the O blood group. The preoperative hypercoagulability status assessed by TEG analysis was reversed 24 h after HES infusion. In conclusion, 6% HES 200/0.6 induced immediate hemostasis alterations. Patients of the O blood group were likely to develop a von Willebrand-like syndrome after HES infusion. We conclude that intraoperative use of 6% HES 200/0.6 should be restricted in patients of the O blood group undergoing surgical procedures with high risk for bleeding.

The in vitro reversal of histamine-induced vasodilation in the human internal mammary artery.

UNLABELLED: Anaphylactic shock therapy includes the use of catecholamines but they may not always be effective. Because vasodilation during anaphylaxis is a result of the endothelial release of multiple mediators, we investigated the effects of epinephrine, vasopressin, and inhibitors of nitric oxide and prostanoid pathways on histamine-induced relaxation in human internal mammary artery. The vessel segments were obtained intraoperatively and were suspended in organ chambers to record isometric tension. Norepinephrine (10(-6) M) was used to precontract the rings followed by histamine (10(-6.5) M) to relax the vessels and mimic vascular collapse. Epinephrine, vasopressin, methylene blue, N(G)-monomethyl-L-arginine (L-NMA) and indomethacin were added in a cumulative fashion to reverse the histamine-induced vasodilation. The internal mammary artery segments exhibited greater contraction in the presence of the epinephrine (4.9 +/- 0.7 g) compared with vasopressin (2.6 +/- 0.7 g). Vasopressin (10(-11) to 10(-7) M), methylene blue (10(-7) to 10(-5) M), L-NMA (10(-6) to 10(-4) M), and indomethacin (10(-7) to 10(-5) M) were only partially effective. These findings suggest that vasopressin and methylene blue may offer a potential therapeutic option in the treatment of histamine-induced vasodilatory shock. IMPLICATIONS: Epinephrine only partially reverses histamine-induced vasodilation in human internal mammary arteries, whereas vasopressin, methylene blue, and drugs involved in the inhibition of nitric oxide and prostaglandin generation lead to a complete reversal of the vascular relaxation.

Lack of mother-to-infant transmission of hepatitis C virus in human immunodeficiency virus-seronegative women: a prospective study with hepatitis C virus RNA testing.

The published risk of mother-to-infant transmission of hepatitis C virus varies according to the population studied and the tests used. In a prospective study we used the polymerase chain reaction to assess the risk of vertical transmission of hepatitis C virus in an unselected population of women uninfected by human immunodeficiency virus. Hepatitis C virus antibodies were sought with a second-generation enzyme-linked immunosorbent assay in 2,367 consecutive pregnant women. Forty-one were positive, and 17 consented to serological follow-up of their offspring (n = 18). A second-generation recombinant immunoblot assay, ALT determination and hepatitis C virus RNA testing were performed on maternal sera obtained during pregnancy and sera from the offspring at birth and thereafter. Five older brothers or sisters were also tested. Hepatitis C virus RNA sequences in serum were amplified with a modified nested polymerase chain reaction procedure with primers from the highly conserved 5' noncoding region of the hepatitis C virus genome. All the neonates were positive for hepatitis C virus antibodies, with enzyme-linked immunosorbent assay titers and recombinant immunoblot assay patterns similar to those of their mothers. After birth hepatitis C virus antibodies gradually disappeared within 6 mo. Hepatitis C virus RNA was consistently negative in the 18 children from birth to 24 mo (range = 3 to 24 mo) and in the 5 older children, regardless of the hepatitis C virus polymerase chain reaction status of the mothers (8 of whom were positive).(ABSTRACT TRUNCATED AT 250 WORDS)

Superoxide production, risk factors, and endothelium-dependent relaxations in human internal mammary arteries.

BACKGROUND: In a variety of disease states, endothelium-dependent vasodilation is abnormal. Reduced nitric oxide (NO) production, increased destruction of NO by superoxide, diminished cellular levels of L-arginine or tetrahydrobiopterin, and alterations in membrane signaling have been implicated. We examined these potential mechanisms in human vessels. METHODS AND RESULTS: Relaxations to acetylcholine, the calcium ionophore A23187, and nitroglycerin, as well as superoxide production and NO synthase expression, were examined in vascular segments from patients with identified cardiovascular risk factors. Endothelium-dependent relaxations were also studied after incubation with L-arginine, L-sepiapterin, and liposome-entrapped superoxide dismutase (SOD) and after organoid culture with cis-vaccenic acid. Relaxations to acetylcholine and to a lesser extent the calcium ionophore A23187 were highly variable and correlated with the number of risk factors present among the subjects studied. Treatment of vessels with L-arginine, L-sepiapterin, liposome-entrapped SOD, or cis-vaccenic acid did not augment endothelium-dependent relaxations. Hypercholesterolemia was the only risk factor associated with high levels of superoxide; however, there was no correlation between superoxide production and the response to either endothelium-dependent vasodilator used. CONCLUSIONS: In human internal mammary arteries, depressed endothelium-dependent relaxations could not be attributed to increases in vascular superoxide production, deficiencies in either L-arginine or tetrahydrobiopterin, or reduced membrane fluidity. Variability in signaling mechanisms may contribute to the differences in responses to acetylcholine and the calcium ionophore A23187.