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M Quintel

Publications and source records attributed to M Quintel.

34 records · Page 2Linked to original sources
PubMed1997

Partial carbon dioxide rebreathing: a reliable technique for noninvasive measurement of nonshunted pulmonary capillary blood flow.

OBJECTIVE: To determine the validity and clinical utility of the partial CO2 rebreathing technique for measurement of nonshunted pulmonary capillary blood flow and cardiac output. DESIGN: Prospective, controlled animal laboratory investigation and clinical trial. SETTINGS: Animal research facility and intensive care unit of a university hospital. SUBJECTS: Fifteen adult sheep, weighting 58 to 78 kg. PATIENTS: Mechanically ventilated patients with different underlying diseases (n = 12) and with adult respiratory distress syndrome (ARDS) (n = 8). INTERVENTIONS: CO2 elimination rate (VCO2) was measured breath-by-breath with a system developed for the study and also by gas collection (validation procedure in patients with different underlying diseases). Partial CO2 rebreathing maneuvers, cardiac output by thermodilution, and blood gas analysis were performed in sheep with lung atelectasis and in patients with ARDS. MEASUREMENTS AND MAIN RESULTS: The degree of correlation between VCO2 measured with the system developed and gas collection was very good (r2 = .95, p < .0001), and bias and precision calculations (1 +/- 9 mL/min) showed close agreement between methods. The overall degree of correlation between partial CO2 rebreathing measurements and cardiac output was moderate (r2 = .54, p < .0001), the noninvasive method tending to underestimate cardiac output, as shown by bias and precision calculations (-1.69 +/- 1.90 L/min). In contrast, the overall degree of correlation between partial CO2 rebreathing measurements and nonshunted pulmonary capillary blood flow was good (r2 = .73, p < .0001). Bias and precision calculations (0.25 +/- 0.83 L/min) showed a tendency for the partial CO2 rebreathing technique to slightly overestimate pulmonary capillary blood flow. Variance differences between partial CO2 rebreathing measurements and cardiac output could be mostly explained by intrapulmonary right-to-left shunt fraction (r2 = .51, p < .0001). CONCLUSIONS: Our results support the use of the system developed for breath-by-breath VCO2 measurements. The lack of agreement between partial CO2 rebreathing measurements and cardiac output was mostly explained by intrapulmonary right-to-left shunt, suggesting that this technique may not be appropriate for monitoring cardiac output in patients with increased venous admixture. In contrast, our results demonstrate that the partial CO2 rebreathing technique is reliable for measurement of the effective nonshunted pulmonary capillary blood flow. This technique may prove useful to guide ventilatory therapy adjustments in an attempt to optimize nonshunted pulmonary capillary blood flow.

Adult↗
PubMed1997

[The role of extracorporeal membrane oxygenation (ECMO) in current neonatology].

Two hundred term or near-term neonates were referred to an ECMO center for severe PPHN associated diseases. In 2 time periods from 1987 to 1991 and from 1992 to December 1995 alternative treatment modes were tried in an attempt to obviate ECMO. During the first time period patients underwent a trial of high-frequency oscillatory (HFOV) ventilation before ECMO. In the second time period patients first received inhaled NO followed by HFOV in non-responders. If this also failed HFOV was combined with iNO. In both time periods about 40% of the patients were spared ECMO treatment by these alternative treatment modalities. INO only benefited 15% of the ECMO candidates who apparently had fared just as well on HFOV alone in the preceding time period. While patients who were improved by iNO were spared HFOV with its potential severe complications, i.e. air leaks and cardiocirculatory instability. More extended long-term studies will have to show which of these 2 treatment modalities (iNO or HFOV) should be given-first priority in an attempt to avoid ECMO in neonates with severe respiratory failure.

Extracorporeal Membrane Oxygenation↗
PubMed1996

[Clinical significance of cytokines Il-6, Il-8 and C-reactive protein in serum of patients with acute pancreatitis].

The detection of cytokines may elucidate the pathophysiological mechanisms that produce early systemic complications in acute interstitial (i) or necrotizing (n) pancreatitis (AP). The increase in the level of cytokines in the blood of patients with AP may correlate with the severity of the disease. In a prospective clinical trial from October 1992 to August 1993, 23 patients with AP were recruited and blood samples taken for cytokine detection by commercially available Elisa kits and C-reactive protein (CRP) by laser nephelometry. Six of 11 patients with nAP died either early (n = 1) or of late septic complications. None died of iAP. The peak of cytokine and CRP level in the first 3 days of hospitalization was used for calculation. The IL-6 concentration in the blood reached up to 2600 pg/ml in the 1st few days, depending on the severity of AP, and dropped to almost zero in the next days, independently of the clinical course. The differentiation of i- versus nAP, using a cut-off line of 600 pg/ml, was correct in 20 patients [87%, sensitivity (SE): 82%, specificity (SP): 91%, P < 0.001]. The blood levels of IL-8 reached a maximum of 1381 pg/ml in the 1st few days, depending on the severity of AP, and showed a correlation with the clinical course in the following days. The peak of IL-8 blood levels indicated correctly the severity of AP in 18 out of 23 patients using a cutoff level of 200 pg/ml (accuracy: 78%, SE: 82%, SP: 75%, P < 0.01). The CRP levels increased up to a maximum of 535 mg/l and indicated the course of AP correctly in 18 out of 22 patients (SE and SP 82%, P < 0.01). There was no correlation between cytokine blood levels and mortality. In the blood samples of five patients with i- or nAP, no TNF-alpha was detectable. The blood levels of IL-6, and to a lesser extent of IL-8 and CRP, can predict the severity and early systemic complications of AP. The excessive rise in cytokines can be explained by the stimulation of immunological cells (macrophages, lymphocytes and endothelial cells) in the course of AP, inducing early systemic complications.

Acute Disease↗
PubMed1996

[Liquid ventilation with perfluorocarbons].

Clark and Gollan demonstrated impressively in 1966 the ability of perfluorchemicals (PFCs) to transport oxygen and to provide gas exchange across the alveolar capillary membrane. PFCs are used for two major medical indications: as artificial blood substitutes and as a medium for liquid ventilation. The PFC perflubron is additionally used as a contrast medium for diagnostic radiologic procedures. For the intravenous application perfluorocarbons have to be emulgated in phospholipids for the intrapulmonary application the sterile pure solution is used. Liquid ventilation can either be performed by a method known as total liquid ventilation (TLV), in which a device is utilised to ventilate with perfluorocarbon the previously perfluorocarbon-filled lung, or as partial liquid ventilation (PLV) in which a conventional mechanical gas ventilator is used to gas ventilate the partially perfluorocarbon-filled lung. A number of studies have demonstrated the efficacy of perfluorocarbon liquid ventilation in improving gas exchange and pulmonary function in a number of animal species in the setting of acute respiratory failure. In 1989 Greenspan reported on the first human liquid ventilation experience in a neonate. More recently human experiences for neonatal, paediatric and adult patients with acute lung injury have been reported. Since 1995 an FDA-approved study to examine the efficacy of PLV in severe respiratory failure in patients of all ages has been undertaken in the United States. The number of PLV-treated patients is still small; if PLV demonstrates its efficacy even in the ongoing human studies, it might be a very effective additional tool for treating severe acute lung injury.

Adult↗
PubMed1996

[C6 fatal trans-vertebral dislocation fracture with tracheal lesion in Bechterew disease. A case presentation].

A fracture of the cervical spine is a dangerous and life-threatening injury in patients suffering from ankylosing spondylitis. A 71-year-old motorist with a long history of ankylosing spondylitis was injured during a car accident. A rare transverse fracture through the body of C6 occurred and in addition a lesion of the trachea was found. This combination of injuries is described for the first time. Special problems relating to the initial rescue, diagnosis and treatment are discussed according to the literature. The necessity of handling the cervical spine with extreme caution during all medical procedures, taking into account the kyphotic deformity is stressed.

Aged↗
PubMed1994

Comparison of serum phospholipase A2, polymorphonuclear granulocyte elastase, C-reactive protein and serum amyloid A with the APACHE II score in the prognosis of multiple injured patients.

This prospective study of 35 multitraumatized intensive care unit patients requiring mechanical ventilation examined the relative utility of four biochemical parameters with a physiological scoring system for predicting lethal outcome. Levels of serum phospholipase A2 (PLA2), serum amyloid A (SAA), polymorphonuclear granulocyte elastase (PMN elastase), and C-reactive protein (CRP) were determined at short intervals during the patient's hospitalization. The first specimen was obtained at the time of admission, and subsequent specimens were drawn at 8 h intervals for the first 48 h and then twice daily until death or convalescence. Calculations of the APACHE II score used the most deranged variables during the first 24 h of admission to assess patient outcome. Additional calculations of the APACHE II score at the time of each blood draw served as an indicator of patient status. The results indicate that during the first 24 h after admission none of the four examined biochemical parameters gives reliable information about the outcome. The APACHE II score provided the earliest indicator of patient outcome (83% sensitivity, 65% specificity). PMN elastase provided useful information first at 32 h (83% sensitivity, 45% specificity) and better at 132 h (86% sensitivity, 86% specificity). CRP was of intermediate use in predicting outcome initially at 72 h (83% sensitivity, 50% specificity) and later at 132 h (86% sensitivity, 93% specificity). PLA2 and SAA were not useful as early indicators of lethal outcome.

APACHE↗
PubMed1994

[Evaluating lung failure and the limits of artificial respiration].

The treatment and outcome of the respiratory failure decisively depend on its pathophysiological background. Besides simple blood gas analysis the investigation of the respiratory mechanics, interstitial lung water and the monitoring of the pulmonary pressure are necessary for an exact diagnosis. As a scoring method of lung failure the classification by Murray and Morell is most common. In addition to normal volume or pressure controlled artificial ventilation the treatment of lung failure sometimes requires new but accepted modes of ventilation as inversed ratio ventilation, permissive hypercapnea and high frequency ventilation. New methods as negative pressure ventilation, extracorporeal lung ventilation and liquid or partial liquid ventilation are not common yet and should be used only under special conditions. As a supplement of these modes of ventilation the application of prostacyclins, nitric oxide, surfactant and inhibitors of the arachidonic pathway is under clinical investigation. A limitation of the treatment of lung failure should be considered in irreversible multiple organ failure.

Critical Care↗
PubMed1993

[Myxedema coma as a rare postoperative complication].

Myxedema coma is characterized by severe lack of thyroid hormones, unconsciousness and serious restriction of vital functions. The mortality rate still ranges between 50 and 80%. In patients with inapparent hypothyroidism myxedema coma occasionally follows surgery, anesthesia or severe infection. A case of myxedema coma following surgery is reported. CASE REPORT. A 46-year-old woman was anesthesized for hip replacement. The intraoperative cardiovascular situation was characterized by hypotension and tachycardia. On the first postoperative day, unexpectedly a cardiac arrest occurred. Resuscitation with high doses of epinephrine was successful. There was no evidence of myocardial infarction, hypoxia and pulmonary embolism as causative factors for cardiac arrest. A pulmonary artery catheter was inserted and showed low cardiac output. Catecholamines and intravascular fluids were administered without hemodynamic improvement. In the next 5 days pneumonia was followed by ARDS and acute renal failure. After successful treatment of these complications the patient remained in deep coma. An intracerebral disease could be excluded by computerized tomography. Evaluation showed low thyroid hormones (T3; T4) and elevated TSH. The diagnosis of a myxedema coma was assumed. After failure of oral therapy with L-thyroxine (0.025-0.05 mg/day) for 10 days, intravenous therapy with 0.5 mg L-thyroxine was performed. Thirty-six hours later the patient regained consciousness, without cardiac complications. The patient progressed uneventfully under oral therapy with 0.1 mg L-thyroxine and was discharged from the hospital 6 weeks later. DISCUSSION. Pathophysiology and symptomatology of a case of postoperative myxedema coma are described (Tables 1-4). In this patient, the following symptoms occurred: low thyroid hormones (T3; T4), elevated TSH, deep coma, decreased ventilatory response to CO2, diminished myocardial contractility under catecholamine stimulation, impaired renal water excretion. After failure of oral substitution of L-thyroxine, intravenous therapy had to be performed in spite of the high risk of further cardiac complications in this patient. This led to complete recovery with normal neuropsychological and cardiopulmonary parameters. CONCLUSION. Myxedema coma is a rare complication in postoperative care, but in cases of inexplicable unconsciousness thyroid failure should be excluded. If myxedema coma is evident, intravenous therapy with L-thyroxine should be performed under the conditions of extended monitoring.

Coma↗
PubMed1991

Clinical evaluation of electrostimulation anaesthesia for hysterectomy.

A prospective randomized study was undertaken to evaluate the efficacy of electrostimulation anaesthesia (ESA) when compared with neurolept anaesthesia (NLA). One hundred patients scheduled for hysterectomy received either ESA or NLA. Higher levels of mean arterial pressure and heart rate in the ESA group make this technique less suitable for patients with a history of arterial hypertension. A higher dose of muscle relaxants was used in the ESA group. Measured stress variables like plasma glucose, cortisol, and iron indicate maintenance of the stress response during ESA. The postoperative questionnaire revealed intraoperative recall in 12% of ESA patients. We conclude that "pure" ESA based on a N2O regimen should be avoided.

Adult↗