Jacques Jamart

Gastroduodenal motility in mechanically ventilated critically ill patients: a manometric study.

ObjectiveTo determine the main characteristics of gastroduodenal motility in mechanically ventilated, critically ill patients. DesignCase series; comparison with a parallel control group. SettingIntensive care unit in a university teaching hospital. PatientsTwelve adult critically ill patients who required >2 days of mechanical ventilation as a consequence of neurologic or respiratory disease. Control sample of 12 overnight, fasting, healthy volunteers. Measurements and Main ResultsPressure changes in the gastric antrum, proximal duodenum, and distal duodenum were simultaneously recorded during a 4-hr period by a multilumen tube (perfused catheter technique). The migrating motor complex and its three successive phases were identified according to usual definitions (phase 1, period of quiescence; phase 2, period of irregular contractile activity; phase 3 or activity front, period of high-frequency, regular contractions). Contractions and activity fronts at each site were quantified. The mean duration of the migrating motor complex was determined in the duodenum, as well as the contribution of each phase (phases 1, 2, 3) to the length of the complete cycle. The propagation characteristics of each activity front were assessed visually.In the patients, the number of contractions was markedly decreased in the antrum, where activity fronts were totally absent. In the duodenum (proximal and distal), the number of contactions and the occurrence of activity fronts were comparable in both groups. Although the duration of the duodenal migrating motor complex was similar in the two groups, the relative contribution of the quiescence period (phase 1) to the total cycle length increased and the contribution of phase 2 decreased in the patients. Three patients exhibited abnormally propagated (retrograde or stationary) activity fronts in the duodenum. ConclusionsGastroduodenal motility is severely impaired in this group of mechanically ventilated patients. Activity fronts of the migrating motor complex never originated in the stomach, which was hypokinetic; qualitative disorders of the migrating motor complex were present in the duodenum. The loss of peristaltic activity in the stomach and, to a lesser degree, in the duodenum is consistent with an important role for motility disorders in the occurrence of digestive microbial overgrowth in such patients. (Crit Care Med 1994; 22:441–447)

Primary prevention of glucocorticoid-induced osteoporosis with intravenous pamidronate and calcium: a prospective controlled 1-year study comparing a single infusion, an infusion given once every 3 months, and calcium alone.

The aim of this study was to compare the action of two regimens of intravenous (iv) pamidronate in the primary prevention of glucocorticoid‐induced osteoporosis (GC‐OP). The primary purpose of the study was to determine whether any differences in bone mineral density (BMD) appeared after 1 year. A secondary endpoint aimed at assessing the remodeling parameters in order to better understand the mechanisms of action of the various regimens. Thirty‐two patients, who required first‐time, long‐term glucocorticoid therapy at a daily dose of at least 10 mg of prednisolone, were studied. Simultaneously with the initiation of their glucocorticoid treatment, patients also were randomly allocated to receive a single iv infusion of 90 mg of pamidronate at the start (group A); a first infusion of 90 mg of pamidronate followed, subsequently, by an iv infusion of 30 mg pamidronate every 3 months (group B); and a daily 800‐mg elemental calcium supplement given as calcium carbonate (group C), which also was taken by patients in groups A and B. Patients were matched for starting glucocorticoid doses, sex, menopausal status, and hormonal replacement therapy. Lumbar spine and hip (total and subregions) BMDs were measured at the outset and repeated at 6‐month intervals by dual‐energy X‐ray absorptiometry (DXA; Hologic QDR‐2000). Bone turnover was assessed by measurement of total and bone‐specific serum alkaline phosphatase activity (B‐ALP), serum osteocalcin (OC), and serum C‐telopeptide cross‐links of type I collagen (CTX). After 1 year, the mean BMD changes for groups A, B, and C were, respectively, 1.7, 2.3, and −4.6% at the lumbar spine; 1.2, 1.2, and −3.1% at the femoral neck; 1.0, 2.6, and −2.2% for the total hip region. No difference was observed between pamidronate regimens but a highly significant difference was observed between both pamidronate regimens and the control group at the lumbar spine (p < 0.001), at the femoral neck (p < 0.01), and for the total hip (p < 0.05). A significant decrease of serum C‐telopeptide was observed, after 3 months, in groups A and B (p = 0.029), but a sustained decrease of bone resorption over time was observed only in group B. As far as BMD evolution over 1 year was concerned, iv pamidronate, given either as a single infusion or once every 3 months, effectively achieved primary prevention of GC‐OP.

Effective prevention of atrial fibrillation by continuous atrial overdrive pacing after coronary artery bypass surgery.

OBJECTIVES The present study was aimed to evaluate the efficacy of a specific algorithm with continuous atrial dynamic overdrive pacing to prevent atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery. BACKGROUND Atrial fibrillation occurs in 30% to 40% of patients after cardiac surgery with a peak incidence on the second day. It still represents a challenge for postoperative prevention and treatment and may have medical and cost implications. METHODS Ninety-six consecutive patients undergoing CABG for severe coronary artery disease and in sinus rhythm without antiarrhythmic therapy on the second postoperative day were randomized to have or not 24 h of atrial pacing through temporary epicardial wires using a permanent dynamic overdrive algorithm. Holter ECGs recorded the same day in both groups were analyzed to detect AF occurrence. RESULTS No difference was observed in baseline data between the two study groups, particularly for age, male gender, history of AF, ventricular function, severity of coronary artery disease, preoperative beta-adrenergic blocking agent therapy or P-wave duration. The incidence of AF was significantly lower (p = 0.036) in the paced group (10%) compared with control subjects (27%). Multivariate analysis showed AF incidence to increase with age (p = 0.051) but not in patients with pacing (p = 0.078). It decreased with a better left ventricular ejection fraction only in conjunction with atrial pacing (p = 0.018). CONCLUSIONS We conclude that continuous atrial pacing with an algorithm for dynamic overdrive reduces significantly incidence of AF the second day after CABG surgery, particularly in patients with preserved left ventricular function.

Effect of dopamine on gastrointestinal motility during critical illness

Objective: To document the action of dopamine on gastrointestinal motility in mechanically ventilated patients. Design: Crossover, randomized, placebo-controlled study. Setting: General intensive care unit (ICU) in a university hospital. Patients: Twelve mechanically ventilated patients in a stable hemodynamic condition, with no contraindication to enteral feeding.¶Interventions: Dopamine (4 μg/kg per minute) and placebo were infused over 8 h (4 h fasting, followed immediately by 4 h nasogastric feeding at 100 kcal per hour) on two consecutive days, in a random order. Pressure changes in the gastric antrum (four sites) and in the duodenum (two sites) were recorded by perfused catheter manometry. Each session started with the institution of dopamine or placebo infusion.¶Measurements and results: The migrating motor complex and its three successive phases were identified (phase I, period of quiescence; phase II, period of irregular contractile activity; phase III or activity front, period of high-frequency, regular contractions). Contractions and activity fronts at each site were quantified during fasting and feeding. The mean duration of the fasting migrating motor complex was determined in the duodenum, as well as the contribution of each phase (phases I, II, III) to the length of the complete cycle. The propagation characteristics of each activity front were assessed visually. The number of contractions was lower in the antrum (p = 0.024) and phase III motor activity higher in the duodenum [incidence of activity fronts (p = 0.008); number of phase III contractions (p = 0.009)] during dopamine infusion than with placebo. These modifications observed under dopamine were related to decreased antral contractions during fasting (p = 0.050), increased incidence of activity fronts during feeding (p = 0.031), and increased number of phase III contractions during fasting (p = 0.037). In both groups (placebo and dopamine) activity fronts rarely started in the antrum, and abnormally propagated activity fronts were found in the duodenum in some patients. Conclusions: Low-dose dopamine adversely affects gastroduodenal motility in mechanically ventilated critically ill patients.

Capillarization of the sinusoids in liver fibrosis: Noninvasive assessment with contrast-enhanced MRI in the rabbit

Sinusoidal capillarization induces microcirculatory changes in liver cirrhosis and fibrosis. The purpose of this study was to assess whether contrast‐enhanced MRI can be used to demonstrate the effects of sinusoidal capillarization in liver fibrosis. Dynamic MRI after injection of a low‐molecular‐weight contrast agent of 0.56 kDa (Gd‐DOTA), and two high‐molecular‐weight contrast agents of 6.47 kDa and 52 kDa (P792 and P717) was performed in rabbits with liver fibrosis induced by cholesterol and diethylstilbestrol. The hepatic distribution volume accessible to the high‐molecular‐weight agents decreased in the rabbits with liver fibrosis (P792: 7.8% ± 1.7% vs. 10.1% ± 1.8% in normal rabbits, P = .038; P717: 6.2% ± 2.1% vs. 9.7% ± 1.6% in normal rabbits, P = .007), whereas the hepatic mean transit time (MTT) of the low‐molecular‐weight agent was increased (15.9 ± 8.0 s vs. 8.8 ± 2.6 s in normal rabbits, P = .015). In rabbits with liver fibrosis, the clearance of indocyanine green (ICG) was correlated with the volume accessible to the high‐molecular‐weight agents (P792: r = 0.810, P = .015; P717: r = 0.857, P = .007). The collagen content of the liver was inversely correlated with the distribution volume of P717 (r = –.833, P = .010) and with the ICG clearance (r = –.810, P = .015). It was concluded that the microcirculatory changes induced by sinusoidal capillarization in liver fibrosis can be demonstrated noninvasively with MRI. Magn Reson Med 49:692–699, 2003.

Prognostic value of cell proliferation markers, tumour suppressor proteins and cell adhesion molecules in primary squamous cell carcinoma of the larynx and hypopharynx.

Abstract. In an attempt to identify molecular prognostic markers, a series of laryngeal and hypopharyngeal carcinomas was examined for PCNA, Ki67, p27Kip1, p53, E-cadherin and CD44 by immunohistochemistry and for DNA content by flow cytometry. No correlation was found between E-cadherin, CD44, p53 or DNA ploidy and the clinicopathological data. The fraction of cancer cells immunolabelled for p27Kip1 correlated with tumour differentiation, but not with lymph node metastasis. In contrast, the PCNA, Ki67 and S-phase fractions of cancer cells were significantly higher in tumours with lymph node metastasis than in those without lymph node metastasis and were correlated with pathological T-stages and with tumour dedifferentiation. In univariate analysis, advanced pathological T-stage, lymph node metastasis and high fractions of cancer cells immunolabelled for PCNA or Ki67 inversely correlated with overall and disease-free survival. In multivariate analysis, lymph node metastasis was the only factor significantly associated with poor survival. The data suggest that immunohistochemical investigation of PCNA and Ki67 and flow cytometric analysis of S-phase fractions may be useful predictive markers of biological aggressiveness in laryngeal carcinomas.

Focal nodular hyperplasia: natural course observed with CT and MRI.

PURPOSE The purpose of this work was to assess the natural course of biopsy-proven focal nodular hyperplasia (FNH). METHOD Eighteen biopsy-proven FNHs in 14 patients (12 women and 2 men) who were followed for at least 6 months with CT and/or MRI were included in the study. The volume of the lesions was calculated twice by two observers using the summation of areas method. Intra- and interobserver variability was assessed by intraclass correlation coefficients. Longitudinal data analysis was performed with generalized estimating equations. RESULTS The volume of FNH was stable in 6 cases, decreased in 10 cases, and increased in 2 cases. Intra- and interobserver variability in size measurements was 5-10%. Intraclass correlation coefficients were >0.992. Longitudinal data analysis showed that there was a general trend of lesion regression. CONCLUSION Long-term follow-up and objective measurements performed in patients with biopsy-proven lesions show that the natural course of FNH is variable. In particular, lesion regression is not rare.

Bone density and markers of bone remodeling in type 1 male diabetic patients

AIMS To assess the prevalence and severity of bone disease in type 1 diabetic patients and to determine serum markers of bone remodeling as well as their relationship with bone mineral density (BMD). METHODS BMD [by dual energy x-ray absorptiometry (DXA)] and serum markers of bone remodeling [osteocalcin, c-terminal telopeptide of type I collagen (CTX)], leptin and osteoprotegerin (OPG) were measured in 42 adult males with type 1 diabetes. Twenty-four non-diabetic subjects served as controls. RESULTS In 40% of the patients, osteopenia at the lumbar spine (L1-L4) and/or at the left hip was found, and 7% met criteria for osteoporosis. L1-L4 BMD z-score was correlated with age (r=0.365, P=0.018) and a similar trend was observed at left hip. L1-L4 BMD z-score was negatively correlated with CTX and osteocalcin (r=-0.343, P=0.028; r=-0.376, P=0.024, respectively). A significant correlation was evidenced between BMD z-score at both lumbar spine and left hip and leptin values (r=0.343, P=0.03; r=0.395, P=0.012, respectively) but after adjustment for weight this correlation was no longer significant. Osteocalcin, CTX and leptin concentrations were comparable between patients and controls, while OPG concentrations tend to be higher in diabetic subjects (P=0.08). CTX was negatively correlated with age (r=-0.390, P=0.012) and positively correlated with osteocalcin (r=0.696, P<0.001). OPG was positively correlated with age (r=0.507, P=0.001). CONCLUSION Our results suggest that in diabetic subjects osteopenia is a relatively frequent complication but bone loss is attenuated with age progression. Whether this is also mediated by OPG and/or leptin remains to be confirmed.

Latex-induced occupational asthma: time trend in incidence and relationship with hospital glove policies.

Background:  Natural rubber latex (NRL) has become as a major cause of occupational asthma (OA) in workers using NRL gloves. Few population‐based studies have assessed the impact of changes in the patterns of glove usage on the incidence of NRL‐induced OA.

MR assessment of red marrow distribution and composition in the proximal femur: correlation with clinical and laboratory parameters.

Abstract Objective. To correlate the MR appearance of the proximal femur marrow with clinical and blood parameters. Design and patients. The proportion of the femoral neck surface area occupied by red marrow was determined on T1-weighted magnetic resonance (MR) images of the hip in a series of 120 subjects, aged from 15 to 75 years, with ten females and ten males per decade, and correlated with clinical data. This parameter and the bulk T1 values of femoral red marrow were determined in 30 other subjects 25–46 years of age and correlated with their blood parameters. Results. In the series of 120 subjects, the proportion of red marrow surface area decreased with age (P<10–4) and was higher in female than male subjects (P<10–4). Within each decade, the proportion of red marrow surface area was higher in females than in males between 25 and 65 years but neither before 25 nor after 65 years. In the series of 30 subjects, the proportion of red marrow surface area and bulk T1 values of femoral red marrow were significantly negatively correlated with hemoglobin blood levels but not with blood cell counts. Conclusion. The MR appearance of proximal femur red marrow is influenced by age and sex. A relationship with hemoglobin blood level is demonstrated.