Post-operative pressure lability and cardiac baroreflex in normotensive patients as a function of age.

BACKGROUND: Pressure lability may be linked to the loss of the cardiac baroreflex. The reduction of the sensitivity of the cardiac baroreflex has not been delineated in the post-operative period according to age in normotensive patients. This study addresses pressure lability and slope of the cardiac baroreflex as a function of age. METHODS: Patients were allocated to the following three groups: young (20-39 years, n=7), middle aged (40-59 years, n=7) and elderly (60-79 years, n=6), and studied before minor intra-abdominal surgery under CO(2) peritoneal insufflation and nitrous oxide-isoflurane-sufentanil anesthesia, up to 24 h after extubation. An electrocardiogram and non-invasive beat-by-beat pressure monitoring (Finapres) allowed offline calculation of the sensitivity of the cardiac baroreflex ('sequence' technique) and standard deviation (SD) of heart rate (HR; HR variability) and systolic blood pressure (SBP; pressure lability). RESULTS: Before anesthesia, (a) an inverse relationship was observed between the slope of the cardiac baroreflex and age and (b) a trend (P<0.09) existed between the slope of the cardiac baroreflex and pressure lability, irrespective of age. During the early post-operative period, young patients returned to their baseline slope of the cardiac baroreflex; no inverse relationship between increased SD of SBP and decreased SD of RR interval was observed. Middle-aged and elderly patients displayed a depressed slope of the cardiac baroreflex both before and after anesthesia. CONCLUSION: At variance with the pre-operative period, no simple inverse relationship was observed between increased pressure lability and depressed HR variability in young patients during the early post-operative period.

Unusual sinus arrhythmia.

A juxtaposition of long and short RR intervals was observed in 2 hypertensive patients recovering from major surgery under spontaneous ventilation. Sinus rhythm was ascertained throughout the recording. These oscillations could not be linked one-to-one to ventilatory cycles.

Spontaneous baroreflex cardiac sensitivity in end-stage liver disease: effect of liver transplantation.

BACKGROUND AND OBJECTIVE: End-stage liver disease is associated with an imbalance in the autonomic nervous system. The purpose of this study was to estimate the effect of liver transplantation on this imbalance. METHOD: The study involved 10 patients undergoing liver transplantation and 9 patients without liver impairment undergoing liver surgery. The spontaneous baroreflex sensitivity was measured before and 1 month after surgery for the liver surgery group; before and 1, 3, 6, 12 and 18 months after orthotopic liver transplantation. RESULTS: The spontaneous baroreflex slope of patients with end-stage liver disease was decreased before liver transplantation compared to the liver surgery group (3.9 +/- 2.5 ms mmHg(-1) vs. 9.9 +/- 5.0 ms mmHg(-1), P = 0.002). The mean slope was significantly increased at 12 and 18 months compared to the pre-transplantation value (3.9 +/- 2.5 ms mmHg(-1) vs. 8.1 +/- 6.6 ms mmHg(-1) and 7.4 +/- 4.8 ms mmHg(-1), respectively; P = 0.042). Nevertheless, further analysis of individual data showed that only four patients exhibited a marked increase in their baroreflex slope 12 months after the liver transplantation whereas it remained decreased in the six others. CONCLUSIONS: These results confirm that the baroreflex sensitivity is depressed in end-stage liver disease in line with an autonomic nervous system imbalance. The liver transplantation reverses this disturbance only in some patients.

Reversal of early acute rejection with increased doses of tacrolimus in liver transplantation: a pilot study.

BACKGROUND: In this pilot study, we present the results of treatment of early (3 months after liver transplantation) acute rejection episodes by increasing only the tacrolimus doses. METHODS: Ten patients who received tacrolimus as primary treatment experienced acute mild (one case), moderate (four cases), or severe (five cases) rejection episodes. Tacrolimus dosing was increased 1-2 mg every 1 or 2 days until hepatic enzymes started to improve. Steroid basic daily doses were kept unchanged. RESULTS: With the daily dose of tacrolimus increased by a median 1.89-fold (range: 1.2-5), alanine aminotransferase, bilirubin, and gamma-glutamyltranspeptidase levels rapidly reached normal values within the first month. During a median follow-up time of 19.5 months (range: 14-24), none of the 10 patients died or lost their graft. Control liver biopsies were done 13.5 months (range: 7-19) after rejection episode in all patients, and none demonstrated evidence of rejection or sequela. CONCLUSION: This pilot study suggests that increasing tacrolimus dosage could be considered as treatment against early acute rejection episodes including the severe grade.

Haemodynamic changes induced by two I:E ratios: a transoesophageal echocardiographic study.

PURPOSE: To assess the effects of controlled ventilation with two I:E ratios on haemodynamic and left ventricular function in mechanically ventilated patients with moderate to severe respiratory disease, using fluctuation of the arterial pressure waveform and the changes in left ventricular areas obtained by transoesophageal echocardiography. METHODS: Nine patients had their lungs ventilated using volume controlled ventilation with two I:E ratios 1:3 and 1:1). Respiratory rate was adjusted so that six cardiac beats occurred during a respiratory cycle. Systolic blood pressure variation (SBPV), left ventricular area variations measured by TEE and haemodynamic variables measured by PA catheter were compared. RESULTS: When compared with I:E (1:3), I:E (1:1) decreased end diastolic area (EDA) throughout the respiratory cycle from 3% to 8% (P < 0.01) and increased SBPV from 6 +/- 1 to 11 +/- 1 mmHg (P < 0.01). In four patients, SBPV was > 12 mmHg with I:E 1:1. Conversely, SBPV was < 10 mmHg in all patients with I:E 1:3. With I:E (1:1), EDA decreased up to 7% during expiration (P < 0.01). The ejection fraction area remained stable for both ventilatory patterns and throughout the ventilatory cycle for a given I:E. The usual invasive haemodynamic variables were unchanged throughout the study, as was PaO2/FIO2. CONCLUSION: In this setting, EDA and SBPV allow beat-to-beat evaluation of left ventricular preload during change of I:E ratio. Switch from I:E 1:3 to 1:1 may be used as a rapid, safe and reversible test to estimate intravascular volume status assessed by changes in SBPV or EDA.

Sympathovagal effects of spinal anesthesia assessed by the spontaneous cardiac baroreflex.

BACKGROUND: The changes in sympathovagal balance induced by spinal anesthesia remain controversial. The spontaneous baroreflex method allows the continuous assessment of the spontaneous engagement of the cardiac baroreflex, giving an index of sympathovagal balance. The purpose of this study was to follow the effects of spinal anesthesia on spontaneous baroreflex sensitivity. METHODS: Continuous electrocardiogram and noninvasive blood pressure were recorded in 24 patients scheduled for elective inguinal hernia repair and randomly assigned to three groups: (1) no volume loading, (2) volume loading of 15 ml/kg lactated Ringer's solution, and (3) continuous infusion of etilefrine (an ephedrine-like drug). Each patient was studied before, during, and after bupivacaine-induced spinal anesthesia (mean sensory block: T4). Spontaneous baroreflex sensitivity and parameters of time-domain analysis of heart rate variability were calculated from 30 min of recording of each period. RESULTS: No significant change in spontaneous baroreflex slope or parameters of time-domain analysis were observed after regional anesthesia in any group. However, three patients experienced episodes of bradycardia and hypotension in the absence of a high block; these three patients showed an increase in spontaneous baroreflex sensitivity and time-domain parameters. CONCLUSIONS: Using a noninvasive, continuous technique to estimate cardiac sympathovagal balance, no significant variation in autonomic balance induced by spinal anesthesia was observed. However, untoward episodes of bradycardia and hypotension occurred in three patients, who could not be prospectively identified by the parameters studied.

[Effects of mechanical ventilation with PEEP on right to left intra-cardiac shunt caused by patent foramen ovale]. / Effets de la ventilation mécanique avec PEP sur le shunt intracardiaque droit-gauche par un foramen ovale perméable.

OBJECTIVE: To assess the presence of a patent foramen ovale (PFO) using colloid contrast transoesophageal echocardiography in mechanically ventilated patient with and without PEEP and it repercussion on PaO2. STUDY DESIGN: Prospective open before-after trial. PATIENTS: Forty-nine mechanically ventilated patients with respiratory failure (PaO2/FiO2 < 250). METHODS: PEEP assessment before and after adding a PEEP = 10 cmH2O. At each level of PEEP, semi-quantification of PFO was performed and arterial blood gases were withdrawn at FiO2 = 1, with 15 min at each level. Semi-quantification of the right-to-left intra cardiac shunt through a patent foramen ovale was obtained using the quantity of microbubbles in the left atrium on a basal short axis view. RESULTS: A PFO was detected in 11 out of 49 patients (22%). A right-to-left shunt developed in one and worsen in three patients when PEEP was added. In patients without a PFO, PaO2 increased significantly (from 119 +/- 10 mmHg to 145 +/- 10 mmHg, P < 0.001). In patients with a PFO, non significant changes occurred (118 +/- 15 mmHg to 120 +/- 17 mmHg). After adding PEEP, the difference between the two groups was significant (ANOVA, P < 0.05). Moreover, a PFO was present during the whole respiratory cycle in two out of 11 patients. These 2 patients exhibited a PaO2 < 100 mmHg with or without PEEP. CONCLUSION: This study suggests that mechanical ventilation with PEEP enhances an intracardiac right-to-left shunt through a PFO. This condition is responsible for the lack of improvement in blood oxygenation when PEEP is added. When a PFO is present all over the respiratory cycle, or when the oxygenation is worsened with PEEP, this positive pressure ventilation should be avoided. The deleterious consequences of mechanical ventilation on venous return may be minimized by partial ventilation and weaning from ventilator.

[Intra-macrophage lipid particles collected by bronchoalveolar lavage: incidence and diagnostic value]. / Particules lipidiques intramacrophagiques recueillies par lavage bronchoalvéolaire: fréquence et intérêt diagnostique.

This study aimed to determine the incidence and diagnostic value of fat-laden alveolar macrophages obtained by bronchoalveolar lavage (BAL). In 128 patients, including 66 patients admitted for multiple trauma, 158 BAL were carried out. However, 41 BAL from 32 patients were excluded because of poor quality of samples (not enough macrophages, too many ciliated cells, or haemorrhage). All the patients were intubated and mechanically ventilated, having pulmonary infiltrates on the chest film. BAL samples were examined after staining with oil-red-O. They were considered to be positive when more than 5% of alveolar macrophages contained fat droplets. Among them 14 out of 47 patients (30%) without multiple trauma were positive; 7/14 had never been given any intravenous lipid infusion, and 5/14 had aspiration pneumonia (as opposed to 3/32 patients with negative BAL). Further 27 patients out of the 49 (55%) with multiple trauma were positive. Among them 10/49 had clinical evidence of fat embolism, however, only 7/10 had positive samples. All these last ten patients had been given intravenous lipid infusions. The rate of positive alveolar macrophages was correlated neither with the plasma triglyceride concentration, nor the Fracture Index Score, nor the delay between the end of the lipid infusion and the BAL. There was no significant difference in PaO2/FIO2 ratio between the patients with positive and negative BAL. Positive BAL was significantly associated with lipid infusions. The data therefore suggest that the presence of fat-laden alveolar macrophages are associated with various pathological pulmonary conditions, particularly aspiration pneumonia and lipid infusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Wegener's granulomatosis with antiproteinase-3 antibodies occurring after Hodgkin's disease.

We describe the first association between Hodgkin's lymphoma and Wegener's granulomatosis, heralded by renal involvement. A 43-year-old man developed rapidly progressive glomerulonephritis requiring chronic hemodialysis 8 months after remission of Hodgkin's lymphoma. At that moment, no extrarenal involvement was found, despite extensive investigation. Antineutrophil cytoplasm antibodies were positive, without specificity for proteinase-3 or myeloperoxydase. Six months after beginning hemodialysis, multiple pulmonary nodules appeared, along with rapid clinical worsening. A surgical biopsy was performed which disclosed a giant cell granuloma. Antimyeloperoxydase antibodies remained negative, whereas proteinase-3 antibodies became positive. Wegener's granulomatosis was diagnosed and treatment with cyclophosphamide and steroids was started. Clinical and radiological improvement occurred promptly. Eleven months after treatment, both Wegener's disease and Hodgkin's lymphoma remained in remission.

Bronchoalveolar lavage in trauma patients for diagnosis of fat embolism syndrome.

Fat embolism syndrome (FES) is a rare but serious complication occurring after long bone fractures. Presence of fat droplets in cells obtained by bronchoalveolar lavage has been proposed as a specific tool for FES diagnosis in trauma patients. We evaluated this technique over a 15-month period in 85 patients. Twenty-eight patients were excluded. The remaining 57 patients were divided into three groups: group 1, 26 patients without trauma as control; group 2, 22 patients with trauma but without evidence of FES; and group 3, nine patients with trauma and evidence of FES. Six of 26 patients in group 1 and nine of 22 patients in group 2 exhibited fat droplets in alveolar macrophages, whereas three of nine patients of group 3 had not. This study suggests that (1) presence of fat droplets in alveolar macrophages is not a reliable method for diagnosis of FES after long bone trauma, and (2) many conditions are associated with fat droplets in alveolar macrophages.