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P Germann

Publications and source records attributed to P Germann.

At least 19 recordsLinked to original sources
PubMed1999

Shivering and shivering-like tremor during labor with and without epidural analgesia.

BACKGROUND: Effective treatment and prevention of hyperthermia and shivering-like tremor during labor is hindered by a poor understanding of their causes. The authors sought to identify the incidence of nonthermoregulatory shivering-like tremor and the factors associated with this activity. METHODS: The authors studied women in spontaneous full-term labor who chose epidural analgesia (n = 21) or opioid sedation (n = 31). Shivering-like tremor and sweating were evaluated by observation. Core temperature was recorded in the external auditory canal using a compensated infrared thermometer. Arteriovenous shunt tone was evaluated with forearm minus fingertip skin temperature gradients; gradients less than 0 were considered evidence of vasodilation. Tremor was considered nonthermoregulatory when core temperature exceeded 37 degrees C and the arms were vasodilated. Pain was evaluated using a visual analog scale. RESULTS: Shivering-like tremor was observed in 18% of 290, 30-min data-acquisition epochs before delivery. The patients were both normothermic and vasodilated during 15% of these epochs. Shivering was observed in 16% of 116 postdelivery epochs and was nonthermoregulatory in 28%. Sweating was observed in 30% of predelivery epochs, and the patients were both hypothermic and vasoconstricted during 12%. The mean core temperature in patients given epidural analgesia was approximately 0.2 degrees C greater than in those given sedation. Hyperthermia was observed during 10 epochs (38.4+/-0.3 degrees C) during epidural analgesia and during 10 epochs (38.4+/-0.3 degrees C) with sedation. The patients were vasoconstricted in more than 50% of these epochs in each group. Multivariate mixed-effects modeling identified high pain scores and vasoconstriction as significant predictors of shivering. There were no predictors for shivering epochs in patients who were simultaneously normothermic and vasodilated. Significant predictors of sweating were time before delivery, high pain scores, hypothermia with vasoconstriction, high thermal comfort, and low mean skin temperature. There were no predictors for sweating epochs in patients who were simultaneously hypothermic and vasoconstricted. CONCLUSIONS: This study confirms the clinical impression that some peripartum shivering-like tremor is nonthermoregulatory. The authors also identified nonthermoregulatory sweating. These data indicate that shivering-like tremor and sweating in the peripartum period is multifactorial.

Adult↗
PubMed1998

Cytokine patterns in patients who undergo hemofiltration for treatment of multiple organ failure.

The excessive uncontrolled activation of inflammatory cells and mediators after trauma or major surgery plays a key role in the development of adult respiratory distress syndrome and multiple organ system failure (MOSF). In the past elevated cytokine levels were shown to influence the outcome of these patients adversely. There are diverging results regarding the removal of circulating cytokines by various methods of hemopurification for clinical improvement of MOSF. Seven patients after trauma or major surgery underwent continuous venovenous hemofiltration (CVVH) for the treatment of severe organ failure of the heart and lungs (Murray score 2.74) but not for renal or liver failure. The cytokine levels were measured at the beginning and 15, 60, 120, and 240 minutes after initiation of CVVH (measure points MP1-5). Clinical improvement during the treatment was monitored, and correlation with cytokine levels was evaluated. Arterially measured tumor necrosis factor alpha rose from 11.14 ng/ml to 17.86 ng/m1 (p < 0.05). Arterial interleukin-6 (IL-6) levels significantly decreased during CVVH from 1284.7 ng/m1 to 557.9 ng/m1; IL-8 levels simultaneously decreased from an initial peak of up to 154.4 ng/m1 at MP3 to 97.3 ng/m1 at MP5. The drop in serum IL-6 and IL-8 levels closely correlated with clinical improvement. After 2 hours of CVVH the hemodynamic situation improved significantly, as revealed by a decrease in catecholamine expenditure, an increase in arterial pressure, and a decrease in pulmonary artery pressure. Moreover, 2 hours after the initiation of CVVH the oxygenation index rose significantly and correlated well with the drop in shunt fraction. The Murray score significantly fell to 1.86. The removal of IL-6 and IL-8 by CVVH after initial stimulation correlates with clinical improvement, which was demonstrated by significantly improved oxygenation and hemodynamics from 2 hours after the initiation of CVVH onward. The elimination of cytokines and several mediators by CVVH may contribute to the cardiopulmonary improvement of critically ill patients. In comparison with the clinical control group (n = 7), which was comparable in terms of MOSF, no intervention led to a similar improvement in cardiorespiratory failure, and overall two of these patients died. Moreover, patients of the control group experienced a significant longer stay at in the intensive care unit.

Adult↗
PubMed1998

Additive effect of nitric oxide inhalation on the oxygenation benefit of the prone position in the adult respiratory distress syndrome.

BACKGROUND: The response to inhaled nitric oxide and prone positioning was investigated in 47 patients with adult respiratory distress syndrome to test the hypothesis that inhalation of nitric oxide when in the prone position would result in additive improvement in oxygenation. METHODS: The authors prospectively studied patients of both genders who were 15 to 75 yr old and had adult respiratory distress syndrome confirmed by computed tomography (lung injury score, 3.1+/-1). RESULTS: Compared with baseline values in the supine position (T1), inhalation of 10 ppm nitric oxide for 1 h (T2) decreased the mean pulmonary artery pressure from 33+/-9 mmHg to 28+/-6 mmHg (P < 0.05; T2 vs. T1) and increased the ratio of the partial pressure of oxygen in arterial blood (PaO2) to inspired oxygen concentration (FiO2) from 115 (median first quartile [Q1] 97, median third quartile [Q3] 137) to 148 (Q1 132, Q3 196) (P < 0.05; T2 vs. T1). Cessation of nitric oxide brought the values back to baseline (T3). Two hours of prone positioning (T4) significantly increased the PaO2:FiO2 ratio (T4 vs. T3). However, after an additional hour of nitric oxide inhalation in the prone position (T5), a significant decrease of the venous admixture (from 33+/-6% to 25+/-6%; P < 0.05) and an increase of the PaO2:FiO2 ratio (from 165 [Q1 129, Q3 216] to 199 [Q1 178, Q3 316] [P < 0.05; T5 vs. T4]) were observed. CONCLUSIONS: In patients with isolated severe adult respiratory distress syndrome, inhalation of nitric oxide in the prone position significantly improved oxygenation compared with nitric oxide inhalation in the supine position or in the prone position without nitric oxide. The combination of the prone position with nitric oxide inhalation in the treatment of severe adult respiratory distress syndrome should be considered.

Adolescent↗
PubMed1998

Addition of nitric oxide to oxygen improves cardiopulmonary function in patients with severe COPD.

STUDY OBJECTIVE: To assess the effect of nitric oxide inhalation on pulmonary hemodynamics and oxygenation in patients with COPD receiving long-term oxygen therapy (LTOT). DESIGN: Prospective study. SETTING: ICU of a university medical center. PATIENTS: A total of 18 (6 female, 12 male) patients with COPD, spontaneously breathing with LTOT. INTERVENTIONS: Oxygenation and hemodynamic variables were measured and calculated at an inspired oxygen fraction (FIO2) adjusted to mimic LTOT conditions (control), and then 1 h after each sequential addition of 5, 10, and 20 ppm nitric oxide to the gas mixture. A newly developed device (Pulmonox) provided both the delivery and continuous analysis of nitric oxide and oxidative nitric oxide products. MEASUREMENTS AND RESULTS: There was a significant improvement in oxygenation at 5 ppm nitric oxide (PaO2/FIO2 ratio improved from 244+/-37 to 303+/-59, p<0.05), but no further improvement at higher doses (ceiling effect). There was a dose-dependent improvement in hemodynamic variables that was maximal at 20 ppm nitric oxide (mean pulmonary artery pressure decreased from 29+/-7 to 24+/-5 mm Hg, pulmonary vascular resistance index decreased from 565+/-321 to 392+/-215 dyne x s x cm(-5) x m(-2), and right ventricular ejection fraction improved from 34+/-6 to 39+/-7%, all p<0.05). CONCLUSION: Prior studies have demonstrated that inhaled nitric oxide may improve or worsen oxygenation in patients with COPD. Our data show an unequivocal improvement in oxygenation (albeit with a ceiling effect at 5 ppm) and pulmonary hemodynamics (dose dependent) in COPD patients receiving LTOT. Further studies are warranted to examine the usefulness of inhaled nitric oxide during acute exacerbations of COPD, or even the possibility of long-term application in patients receiving LTOT.

Administration, Inhalation↗
PubMed1997

Effects of inhaled nitric oxide and extracorporeal membrane oxygenation on pulmonary hemodynamics and lymph flow in oleic acid lung injury in sheep.

OBJECTIVE: To compare the effects of inhaled nitric oxide (NO) and extracorporeal membrane oxygenation (ECMO) on oxygenation, hemodynamics, and lymphatic drainage in an oleic acid lung injury model in sheep. DESIGN: Prospective, randomized study. SETTING: Animal research laboratory. ANIMALS: Thirty female sheep, weighing 35 to 40 kg. INTERVENTIONS: Acute lung injury was induced by central venous injection of oleic acid (0.5 mL/kg body weight). A chronic lymph fistula had been prepared through a right thoracotomy 3 days before the experiment. Animals were assigned randomly to the NO group (n = 14) or the ECMO group (n = 16). When a lung injury score of > 2.5 was achieved, the animals were given NO in dosage increments of 2, 5, 10, 20, and 40 parts per million (ppm), or placed on ECMO with an FIO2 of 0.21 (ECMO-21) and then 1.0 (ECMO-100) at the oxygenator. Mechanical ventilator parameters were kept constant to isolate the effects of NO and ECMO on systemic and pulmonary hemodynamics, cardiac output, oxygenation parameters, lymph/plasma protein ratio, and lymph flow. Measurements and calculations were performed after 1 hr at each individual step of NO concentration or FIO2. MEASUREMENTS AND MAIN RESULTS: In the ECMO group, PVRI and MPAP did not change and were significantly different from the NO group. In the NO group, there was a dose-dependent decrease in venous admixture, maximal at 10 ppm NO and decreasing from 40 +/- 6% to 23 +/- 10% (p < .05). This decrease was significantly different from the ECMO group, where there was no change. There was a significant increase in PaO2/FIO2 in the NO group, maximal at 10 ppm NO (84 +/- 11 to 210 +/- 90, p < .05), but a greater increase in PaO2/FIO2 on ECMO-21 (81 +/- 14 to 265 +/- 63) and a further increase on ECMO-100 (398 +/- 100) (p < .05). The lymph/plasma protein ratio remained unchanged in both groups after induction of lung injury by oleic acid. However, lymph flow decreased by 11 +/- 6% in the NO group, whereas it increased by 14 +/- 17% in the ECMO group (p < .05). CONCLUSIONS: In an oleic acid-induced sheep model of acute lung injury, there were significant differences between the effects of NO and ECMO on acute pulmonary hypertension, hypoxemia, hypercarbia, and lymph flow. NO significantly decreases pulmonary hypertension, whereas pulmonary hemodynamics were not substantially affected by ECMO. Both interventions reversed hypoxemia, but ECMO did so to a greater degree, and only ECMO improved hypercarbia. Only NO decreased lymph flow, possibly as an effect of decreased microvascular filtration pressure. This study did not attempt to evaluate the impact of these interventions on ventilatory requirements, barotrauma, or outcome. However, this model suggests that NO therapy may moderate pulmonary hypertension and improve lymph flow in acute lung injury. Clinical studies are needed to assess whether NO therapy might be beneficial in treatment of severe acute lung injury in older children and adults.

Administration, Inhalation↗
PubMed1997

The HELLP syndrome.

Explore the source record for details and available documents.

Analgesia, Obstetrical↗
PubMed1996

Safety and efficacy of increasing dosages of glycyl-glutamine for total parenteral nutrition in polytrauma patients.

Supplementation of parenteral nutrition with glutamine (GLN) has been suggested to improve the efficacy of nutritional support by stimulating protein synthesis and improving immunocompetence. In the present study we investigated the impact of infusing the dipeptide glycyl-glutamine (GLY-GLN) at increasing dosages on plasma amino acid concentrations in patients with polytrauma. Nine polytraumatized patients were randomly assigned according their age and their trauma score to three experimental groups. Group 1 received 280, group II 450, and group III 570 mg GLY-GLN per kg body weight/day for a period of four days (3rd to 7th posttraumatic day), resulting in a maximum daily GLN administration (calculated for a 70 kg patient) of 14 g, 21 g and 28 g, respectively. Seven polytraumatized patients receiving the nutrition solution without GLY-GLN supplementation served as controls. All patients received total parenteral nutrition with an average amino acid administration of 1.1 g/kg/day and a total energy intake of 30 kcal/kg/day. GLY-GLN infusion did not evoke any side effects. In comparison with the control group, arterial plasma GLN concentrations increased significantly on day I after start of infusion in groups II and III, but remained raised throughout the study period only in group III (p < 0.003). Similarly, plasma GLY concentrations were also significantly raised in group III (p < 0.04). The maximum increase of plasma GLY was found on the second infusion day, after which plasma concentrations of GLY fell to concentrations even below those observed in the control group at the end of the study period. Excretion of GLY-GLN, GLN or GLY in the urine during the GLY-GLN infusions was negligible. We conclude from this first available dose finding study on glutamine-containing dipeptides that in polytraumatized patients infusion of 570 mg/kg/day of GLY-GLN (corresponding to 28 g glutamine or 40 g dipeptide/70 kg, respectively) is necessary to induce a sustained effect on plasma glutamine concentrations. No pathological accumulation of free glycine or of the dipeptide was seen with any of the three dosage steps of GLY-GLN. Thus, the administration of even high doses of GLY-GLN is feasible and safe in patients with polytrauma and is not associated with any relevant renal substrate loss.

Adult↗
PubMed1995

Position of jugular oxygen saturation catheter in patients with head trauma: assessment by use of plain films.

OBJECTIVE: The purpose of this study was to establish a plain radiographic technique for the assessment of the position of a jugular oxygen saturation catheter in patients with head trauma. MATERIALS AND METHODS: In the experimental study, jugular oxygen saturation catheters were introduced into the internal jugular veins of four cadavers. Correct positioning of the catheter tips was monitored by CT. Concurrent anteroposterior radiographs of the skulls were obtained with the tubes angled in a transverse plane and in a sagittal plane at intervals of 5 degrees and within a total range of 70 degrees for each plane. Three radiologists judged the visibility of the catheter tips and measured the distance of the catheter tips to previously determined bony landmarks of the skull. Then, preliminary radiologic criteria for correct positioning of the catheters were defined. In the clinical study, we prospectively evaluated radiographs for 32 patients who received jugular oxygen saturation catheters. Eleven patients had digital radiographs done, and 21 patients had radiographs with a conventional screen film system done. Radiographs were analyzed for consistency of findings with the experimental results and for consistency of the suspected catheter position with laboratory data. RESULTS: Results of the cadaveric study showed that catheter position is best assessed on strict anteroposterior radiographs with the orbitomeatal-basal line perpendicular to the plane of the film. A correctly positioned catheter tip should lie cranial to a line extending from the atlantooccipital joint space and caudal to the lower margin of the orbit. The catheter tip also should lie cranial to a line connecting the tips of the mastoid processes, with a catheter tip-to-line distance averaging 20% of the overall distance between the tips of the mastoid processes. According to these criteria, the catheter was properly positioned in 26 of 32 patients. In three patients, the catheter obviously was improperly positioned. Catheter position was equivocal in three other patients; in two of these patients, the catheter was looped within the internal jugular vein. Whereas for all 26 patients with properly positioned catheters values for jugular venous oxygen saturation were congruent with other laboratory data, incongruent saturation values were recorded for five of the six patients with equivocally or obviously improperly positioned catheters. CONCLUSION: Accurate assessment of the position of a jugular oxygen saturation catheter can be made by use of specific bony landmarks seen on anteroposterior radiographs of the skull.

Brain Edema↗
PubMed1994

Barbiturate attenuation of agonist affinity in cerebral arteries correlates with anesthetic potency and lipid solubility.

Barbiturates are known to reduce agonist sensitivity (EC50) in vascular smooth muscle; we provide evidence that the reduced agonist sensitivity can be correlated with a reduction in agonist affinity for its receptor. The histamine receptor was chosen since this agonist caused a consistent and maximum contraction of the cerebral artery used in this study. Segments of the basilar artery of white New Zealand male rabbits were set up in a small-vessel myograph in physiological salt solution, kept at 37 degrees C, pH 7.4, and bubbled with a 95% oxygen and 5% carbon dioxide gas mixture. The equilibrium dissociation constant (KA) of histamine for its receptor was calculated according to Furchgott's method by making three concentration-response curves to histamine: control, in the presence of phenoxybenzamine (0.02 microM), and after addition of a barbiturate in concentrations between 0.1 and 1.0 mM. All barbiturates tested, i.e., thiamylal, thiopental, pentobarbital, and phenobarbital, significantly reduced both histamine sensitivity and affinity. There is a significant correlation between histamine sensitivity and receptor affinity for histamine in a series of arterial segments from different animals. The attenuation of both pharmacological properties was consistent with the known rank order of anesthetic potency and with lipophilicity (r = 0.98; p < 0.05). Receptor reserve did not correlate with sensitivity. Thus, most of the change in receptor sensitivity was due to a change in agonist affinity. We suggest that barbiturates alter agonist receptor affinity by causing a perturbation in the membrane lipid environment of the receptor, leading to a conformational change, although alterations in intracellular mechanisms cannot be excluded.

Animals↗
PubMed1994

Neurogenically evoked cerebral artery constriction is mediated by neuropeptide Y.

We examined the proposal that neuropeptide Y (NPY) released from nerve endings constricts cerebral arteries. Neurogenic vasoconstriction of rabbit basilar arteries is of adrenergic origin but is resistant to blockade by classical alpha-adrenoceptor antagonists. Tetrodotoxin-sensitive contractions of the rabbit basilar artery were elicited by transmural stimulation of nerves. The contractions were inhibited by incubation of tissues with an antiserum to NPY (0.32 microL undiluted immune serum/mL); addition of prazosin (0.1 microM) did not further attenuate the nerve-mediated contraction. The antiserum to NPY also antagonized vasoconstriction due to exogenously administered NPY and was without effect on responses due to histamine or angiotensin. Our results indicate that neurogenic vasoconstriction of the rabbit basilar artery is largely due to the release of NPY and that it is unlikely that other vasoconstrictors contribute significantly to the increased tone.

Animals↗