Search PubMed⌕ Search

Biomedical subjects

T Hachenberg

Publications and source records attributed to T Hachenberg.

At least 19 recordsLinked to original sources
PubMed2006

Anesthetic considerations in patients with previous thoracic surgery.

PURPOSE OF THE REVIEW: This review presents an overview of the different problems and challenges after thoracic surgery. It covers the pathophysiological changes that may occur regularly in the early and late period following surgery. In addition, surgical complications with anesthesiological implications for diagnosis, treatment and prevention are discussed, and consequences for anesthesia in further major and thoracic surgical procedures are shown. RECENT FINDINGS: During the last decade, complications in the early period following surgery after thoracotomy have increasingly moved into the focus caused by their high morbidity and mortality. These problems, such as hemorrhagia and bronchopleural fistulas, are important because they call for a prompt revision or even an emergency operation. The therapy of acute bleeding follows general anesthesiological guidelines whereas the bronchopleural fistula demands methods to prevent aspiration pneumonia as a first priority. In the late period following surgery, typical cardiac and pulmonary modifications can be described that persist and have anesthesiological implications in the case of further surgery. Recent literature, however, lacks clear recommendations regarding anesthesiological management and practice for these cases. SUMMARY: Current literature presents no general recommendations on how to manage patients after recent thoracic surgery. Therefore it is necessary to find an individual strategy to handle possible complications and well known pathophysiological changes. Knowledge and understanding of the etiology, the pathophysiology and the risk factors of the perioperative period, allows prevention and target intervention aimed at reducing morbidity and mortality following surgery.

Anesthesia↗
PubMed2005

Influence of muscle relaxation on neuromonitoring of the recurrent laryngeal nerve during thyroid surgery.

BACKGROUND: The influence of muscle relaxation on the intra-operative neuromonitoring of the recurrent laryngeal nerve during thyroid surgery is unclear. METHODS: In a prospective study involving 200 patients undergoing elective thyroid surgery, the influence of muscle relaxation on neuromonitoring of the recurrent laryngeal nerve was investigated. The patients received balanced anaesthesia with oxygen-nitrous oxide-isoflurane, and rocuronium bromide was used as the non-depolarizing neuromuscular blocking agent. The degree of relaxation was monitored continuously by accelerometry [twitch (% TW)]. Summed action potentials (SAcP) obtained from the vocalis muscle were characterized by the area under the electromyographic curve expressed in millivolt seconds. RESULTS: Evoked potentials were obtainable in all patients and at all time points. With decreasing neuromuscular blockade a significant increase in the potentials evoked at the vocalis muscle was observed. At 0% TW SAcP was 1.27 (SD 1.02) mV s. An increase in TW to 10% was accompanied by an increase in SAcP to 2.68 (2.01) mV s (P<0.01). At a TW of 25%, mean SAcPs of 5.08 mV s were recorded. CONCLUSIONS: There was a significant difference in the degree of relaxation of the adductor pollicis muscle and the vocalis muscle. The laryngeal muscles exhibited a shorter response time than the adductor pollicis and recovered more quickly. These results confirm the feasibility of intra-operative neuromonitoring of the recurrent laryngeal nerve during neuromuscular blockade.

Action Potentials↗
PubMed2005

[Open heart tricuspid valve replacement in a heroin addict Anaesthesiological management].

A 24-year-old female with a history of former heroin addiction underwent open heart surgery for a mechanical tricuspid valve replacement. Anaesthesiological management included a thoracic epidural catheter at the Th(2)/Th(3) segments and balanced general anaesthesia (remifentanil, desflurane/propofol). Additionally, clonidine (2 microg*kg(-1)*h(-1)) was continuously administered. Pain therapy was achieved using 0.375% ropivacaine via a thoracic epidural catheter (4 ml*h(-1)) and metamizole (4 x 1 g/day) intravenously. With this concept we were able to achieve an appropriate anaesthesia and analgesia and the operation was carried out without complications.

Adrenergic alpha-Agonists↗
PubMed2005

Effects of different anaesthetic agents on immune cell function in vitro.

BACKGROUND AND OBJECTIVE: Anaesthesia may affect the regulatory balance of postoperative immune response. The aim of this study was to investigate the effects of different volatile and non-volatile anaesthetic agents and particularly of clinically used agent combinations on the proliferation capacity and cytokine production of immune cells. METHODS: Peripheral blood mononuclear cells from healthy donors were PHA-activated in the presence or absence of various concentrations of thiopental, propofol, fentanyl, sufentanil, sevoflurane, nitrous oxide and combinations of these anaesthetics. Cell proliferation was assessed by tritiated thymidine uptake. Interleukin-2 production and release of the soluble IL-2 receptor were determined by enzyme immunoassays and used as measures of lymphocyte activation. RESULTS: Thiopental inhibited cell proliferation in a dose dependent manner (P < 0.001) and reduced sIL-2R release (2090-970 microg mL(-1); P < 0.05). Propofol reduced sIL-2R release at the high concentration of 10 microg mL(-1) (2220 pg mL(-1) 1780 microg mL(-1); p < 0.05). Fentanyl and sufentanil did not compensate for or enhance the inhibitory effects of thiopental. Nitrous oxide, but not sevoflurane, reduced the proliferation of human peripheral blood mononuclear cells (P < 0.05). In combinations with thiopental or nitrous oxide, sevoflurane compensated the inhibitory effects of these two agents. Fentanyl, sufentanil, sevoflurane and nitrous oxide did not affect PHA-induced IL-2 and sIL-2 receptor release by human peripheral blood mononuclear cells. CONCLUSION: Thiopental and nitrous oxide have immunosuppressive activity. In contrast, sevoflurane may have a beneficial effect by alleviating the immunosuppressive effects of both substances.

Adult↗
PubMed2004

[Is the pneumoperitoneum minimally invasive during laparoscopic colonic surgery?].

The importance of laparoscopic colonic surgery has increased considerably in the past decade. However, a minimally invasive operation with induction of pneumoperitoneum does not imply a minimally invasive anaesthesia. The haemodynamic effects of intraperitoneal carbon dioxide insufflation depend an the extent of intraabdominal pressure elevation, severity of preexisting cardiopulmonary diseases, alterations of arterial PCO (2) and pH, volume state of the patient and co-medications. In addition, positioning of the patient for laparoscopic colonic surgery and endocrinological reactions during and after induction of pneumoperitoneum may significantly affect systemic and pulmonary haemodynamics. Intraabdominal operations may impair respiratory function independent from anaesthesia. Preoperative evaluation of the high risk patient is of utmost importance. Assessment of expiratory PCO (2), extended cardiopulmonary monitoring and maintenance of intraabdominal pressure in the range of 5 - 7 mmHg are recommended during laparoscopic colonic surgery.

Abdominal Wall↗
PubMed2003

Cardiopulmonary effects of non-invasive positive pressure ventilation (NPPV)--a controlled, prospective study.

BACKGROUND: This study was undertaken to investigate the haemodynamic effect of non-invasive positive pressure ventilation (NPPV) in patients after cardiac surgery. NPPV has recently become popular as method for treating acute respiratory failure. Its influence on cardiopulmonary haemodynamics is still unknown. METHODS: 30 extubated low-risk patients were included in four study intervals after cardiac surgery. During the first and the third interval, the patients breathed spontaneously and received oxygen via face mask for 45 min. Both intervals were followed by 45 min on NPPV. RESULTS: Cardiac index increased significantly from 2.8 to 3.1 ml/min/m2 during NPPV (p < 0.001) and from 2.7 to 3.2 ml/ min/m2 (p < 0.001). Mixed venous saturation rose significantly from 72.4 to 74.8 % (p < 0.001) and from 72.1 to 75.4 % (p < 0.001) during NPPV while the oxygen extraction ratio decreased from 25.5 and 26.1 % to 23.0 (p < 0.001) and 22.6 % (p < 0.001) during NPPV. At the same time, urine production increased significantly from 182 to 328 ml/h and from 186 to 285 ml/h (p < 0.001). Heart rate and mean arterial blood pressure rose significantly during NPPV. There were no significant changes in systemic and pulmonary haemodynamics, oxygenation or CO 2 elimination. CONCLUSIONS: NPPV improves CI significantly in stable cardiac surgery patients. Factors other than blood pressure, vascular resistance or blood gases must exert an additional influence on CI. They are still not identified. Changes in transmural pressure during NPPV may play an important role.

Cardiac Output↗
PubMed2001

Endocrine effects of dopexamine vs. dopamine in high-risk surgical patients.

OBJECTIVES: To compare the endocrine effects of dopexamine and dopamine on prolactin (PRL), dihydroepiandrosterone sulfate (DHEAS), cortisol, thyrotropin (TSH), and peripheral thyroid hormone serum concentrations in surgical patients at risk of developing postoperative complications because of hypoperfusion of various organ systems. DESIGN AND SETTING: A prospective, randomized, placebo-controlled, blinded clinical trial in an adult surgical intensive care unit in a university hospital. PATIENTS: Thirty-two male surgical risk patients undergoing elective major abdominal surgery. INTERVENTIONS: Patients were randomized to receive placebo ( n=8), dopexamine (0.5 microg kg(-1) min(-1), n=8), dopexamine (1 microg kg(-1) min(-1), n=8) or dopamine (5 microg kg(-1) min(-1), n=8) on the first postoperative day. MEASUREMENTS AND RESULTS: All patients received either a placebo or catecholamine infusion for 24 h. Blood samples were obtained every 2 h for the next 2 days. PRL, DHEAS, cortisol, TSH, triiodothyronine, thyroxin, free triiodothyronine, and free thyroxin serum concentrations were determined by radioimmunoassay or luminescence immunoassay. Dopexamine (0.5 microg kg(-1) min(-1)) had no effects on serum concentrations of PRL or TSH. Higher doses of dopexamine (1 microg kg(-1) min(-1)) suppressed PRL secretion significantly, but not TSH. In contrast, infusion of dopamine (5 microg kg(-1) min(-1)) completely inhibited PRL and TSH secretion. DHEAS, cortisol, and thyroid hormone serum concentrations were not affected by either dopexamine or dopamine infusion. Measurements of hemodynamic parameters, peripheral oxygen saturation, diuresis, blood gases, and standard laboratory parameters were repeated hourly. Significant differences were not found between placebo, dopexamine (0.5 microg kg(-1) min(-1)) and dopamine (5 microg kg(-1) min(-1)) group. Dopexamine at 1 microg kg(-1) min(-1) increased the heart rate significantly. CONCLUSIONS: Routine postoperative optimizing of men undergoing abdominal surgical procedures with dopexamine at higher doses or dopamine induces at least partial hypopituitarism, which may possibly affect postoperative morbidity.

Abdomen↗
PubMed2000

[Acute traumatic myocardial infarction with cardiogenic shock in severe polytrauma--a case report].

A 41-year-old man suffered severe polytrauma and developed a traumatic myocardial infarction with cardiogenic shock. Thrombolysis as well as coronary bypass grafting was contraindicated due to accompanying injuries. An attempted early coronary revascularization by percutaneous transluminal coronary angioplasty (PTCA) failed due to dissection of the left interventricular coronary artery. Treatment of cardiac insufficiency was complicated by intraabdominal haemorrhage enforcing emergency laparotomy. Intraaortic balloon counterpulsation proved to be efficient in supporting circulation in these circumstances. The case report documents the practicability and importance of treating both myocardial ischaemia and attending injuries in an equivalent and coordinated manner in traumatic myocardial infarction.

Adult↗
PubMed2000

Induction of P-glycoprotein by rifampin increases intestinal secretion of talinolol in human beings: a new type of drug/drug interaction.

BACKGROUND: P-Glycoprotein is an efflux pump in many epithelial cells with excretory function. It has been demonstrated that rifampin (INN, rifampicin) induces P-glycoprotein, particularly in the gut wall. We therefore hypothesized that rifampin affects pharmacokinetics of the P-glycoprotein substrate talinolol, a beta1-blocker without appreciable metabolic disposition but intense intestinal secretion in human beings. METHODS: Pharmacokinetics of talinolol (a single dose of 30 mg administered intravenously or 100 mg administered orally for 7 days) and duodenal expression of the MDR1 gene product P-glycoprotein as assessed by reverse transcriptase-polymerase chain reaction of the MDR1-messenger ribonucleic acid, by immunohistochemistry and Western blot analysis were analyzed before and after coadministration of rifampin (600 mg per day for 9 days) in 8 male healthy volunteers (age 22 to 26 years). RESULTS: During rifampin treatment, the areas under the curve of intravenous and oral talinolol were significantly lower (21% and 35%; P < .05). Treatment with rifampin resulted in a significantly increased expression of duodenal P-glycoprotein content 4.2-fold (2.9, 6.51) (Western blot) and messenger RNA was increased in six of the eight volunteers. P-Glycoprotein expression in biopsy specimens of gut mucosa correlated significantly with the systemic clearance of intravenous talinolol (rs = 0.74; P < .001). CONCLUSIONS: Rifampin induces P-glycoprotein-mediated excretion of talinolol predominantly in the gut wall. Moreover, clearance of talinolol from the blood into the lumen of the gastrointestinal tract may be predicted by the individual intestinal P-glycoprotein expression. Thus we describe a new type of steady-state drug interaction affecting compounds that are subject to transport rather than metabolism.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

[Perioperative management with short-acting intravenous anesthetics].

Total intravenous anaesthesia (TIVA) with short-acting drugs is a standard procedure for day case surgery and is increasingly used for neurosurgical, cardiac surgical and paediatric surgical operations. The combination of propofol with alfentanil or remifentanil is frequently applied due to its favourable pharmacological properties. Propofol is characterized by a large volume of distribution at steady state and a relatively long elimination half time (t1/2 beta). Because of a high metabolic clearance, the clinical effects of propofol decline rapidly even after prolonged intravenous drug infusion. In patients with increased age, obesity or liver or renal failure, decreased doses of propofol for induction of anaesthesia are recommended. The short-acting opioids alfentanil and remifentanil provide small volumes of distribution at steady state, a short blood-brain equilibration time and decreased t1/2 beta. Remifentanil has unique pharmacological properties due to an ester binding and its elimination via extrahepatic hydrolysis by non-specific blood and tissue esterases. The context sensitive half time of remifentanil is significantly shorter than that of other opioids. Its analgetic potency is equal to fentanyl and 20 to 30 times higher than alfentanil. The advantages of total intravenous anaesthesia include fewer haemodynamic side-effects, a decreased incidence of postoperative nausea and vomiting and less neurohumoral stress response to surgery. Adequate pain therapy is mandatory after total intravenous anaesthesia with short-acting drugs. Continuous infusion of remifentanil for postoperative analgesia or supplementation of regional anaesthesia requires careful monitoring of vital functions. The economic aspects of TIVA remain to be determined.

Adult↗
PubMed1999

[Acute failure of the intestinal barrier--pathophysiology, diagnosis, prophylaxis and therapy].

The gut not only serves as a main target for the detrimental effects of stress during and after surgery, but may also promote the development of multiple organ failure after different types of severe shock. According to a current hypothesis, an impaired intestinal barrier function is associated with a decreased separation of intraluminal bacteria and toxins and systemic circulation, which may induce sepsis and multiple organ failure. Hypoperfusion during shock, reperfusion injury of the splanchnic mucosa, alterations of the micro-ecology of the gut and immunologic and hormonal disturbances are important underlying pathophysiological mechanisms. Various therapeutic concepts have been proposed such as improvement of splanchnic perfusion, nutritive and metabolic treatment by means of immunomodulating nutrients, parenteral substitution of glutamine, early onset of enteral nutrition, normalization of gut motility and selective decontamination of the gut. However, no clinical study to date could clearly demonstrate a key role of the gut in the pathogenesis of sepsis and multiple organ failure. Likewise, the efficacy of different prophylactic and therapeutic procedures remain to be studied. An aggressive treatment of shock and avoidance of microcirculatory disturbances are of principal importance for prophylaxis of multiple organ failure.

Acute Disease↗
PubMed1998

[Ventilation-perfusion distribution with volume-reduced, pressure-limited ventilation with permissive hypercapnia].

PURPOSE: Low volume pressure-limited ventilation with permissive hypercapnia (PH) may decrease the mechanical stress of the lung in acute respiratory insufficiency. Alveolar PCO2 is a determinant of regional ventilation, whereas increased mixed-venous and arterial PCO2 may affect systemic and pulmonary haemodynamics. The aim of this study was to analyse the ventilation-perfusion (VA/Q) distribution during controlled ventilation with permissive hypercapnia. METHODS: The study was approved by the ethical committee of the Ernst-Moritz-Arndt University of Greifswald. Eleven patients with severe ARDS (lung injury severity score 2.77 +/- 0.47) were studied. Intrapulmonary shunt (QS/QT, % of QT), lung areas with 0.005 < or = VA/Q < or = 0.1 ("low" VA/Q, % of QT), lung areas with 10 < or = VA/Q < or = 100 ("high" VA/Q, % of VE), dead space ventilation (VD/VT = VA/Q > 100, % of VE) and the mean distribution of ventilation (Vmean VA/Q) and perfusion (Qmean VA/Q) were determined by the multiple inert gas elimination technique during normocapnic (NC) and hypercapnic (HC) mechanical ventilation. In addition, systemic mean arterial and pulmonary arterial pressure, cardiac output (CO) and arterial and mixed venous partial pressures for oxygen (PaO2, PvO2) and carbondioxide (PaCO2, PvCO2) were assessed. RESULTS: Low-volume pressure-limited ventilation was associated with moderate hypercapnia (PaCO2 = 61 +/- 12 mmHg vs. 39 +/- 6 mmHg, p < 0.01). QS/QT increased (28 +/- 16% [NC] vs. 36 +/- 17% [HC], p < 0.05), whereas Qmean VA/Q decreased from 1.01 +/- 0.37 (NC) to 0.65 +/- 0.49 (HC), (p < 0.01) and Vmean VA/Q decreased from 1.54 +/- 0.58 (NC) to 1.12 +/- 0.93 (HC) (p < 0.05). Hypercapnia induced mild systemic hypotension and pulmonary hypertension. CO increased from 10.8 +/- 2.3 l/min to 11.6 +/- 2.6 l/min (p < 0.05). PaO2 was almost unchanged, but PvO2 increased significantly from 40 +/- 4 mmHg (NC) to 49 +/- 7 mmHg (HC) (p < 0.01). CONCLUSION: The mechanical ventilation with permissive hypercapnia may increase shunt due to alveolar derecruitement and an impaired hypoxic pulmonary vasoconstriction. PaO2 was unchanged due to an increased CO, PvO2 and--to a lesser extent--shift of the oxyhaemoglobin dissociation curve.

Adult↗
PubMed1998

[Dissociative stupor--differential diagnosis of coma following injury].

Two cases are described in which a dissociative stupor originating from conversion neurosis simulated a coma following a sustained trauma. At first both patients showed no response to being addressed or to pain stimuli. They presented an upward eye gaze deviation, cardiorespiratory functions were stable. Following extensive diagnostic procedures revealing no organic cause for the clinical symptoms, the diagnosis of a hysterical consciousness disorder was stated. Symptoms of conversion neuroses include lacking call response, gait disorder, seizure-like conditions and strength diminution in one or more extremities. In these cases suspicious facts are the absence of injuries (for example by falling down or tongue bite during a dissociative attack), eye gaze deviation and the phenomenon that, when the patient's arm is raised above the head and let fall, it never hits the face but glides down beside the body.

Adult↗
PubMed1998

The effect of dopexamine on ventilation perfusion distribution and pulmonary gas exchange in anesthetized, paralyzed patients.

UNLABELLED: We studied the effects of the beta2-adrenoceptor and DA1-receptor agonist dopexamine on ventilation perfusion (V(A)/Q) distribution in anesthetized, paralyzed patients (n = 17) undergoing major abdominal surgery. Intrapulmonary shunt (Q(S)/Q(T)) (percentage of cardiac output [CO]), perfusion of low V(A)/Q areas (percentage of CO), ventilation of high V(A)/Q areas (percentage of total ventilation [V(E)]), and dead space ventilation [percentage of V(E)]) were calculated from the retention/excretion data of six inert gases. In the control state, Q(S)/Q(T) was 11% +/- 9% (mean +/- SD) and little perfusion of low V(A)/Q areas (3% +/- 4%) was observed. Infusion of 1.0 microg kg(-1) x min(-1) dopexamine had no effect on Q(S)/Q(T) and low V(A)/Q areas despite an increased CO (7.7 +/- 2.2 L/min versus 6.2 +/- 1.2 L/min; P < 0.01). Pao2 increased from 15.5 +/- 5.6 kPa (116 +/- 42 mm Hg) to 17.3 +/- 6.3 kPa (130 +/- 47 mm Hg) (P < 0.05). Infusion of 2.0 microg x kg(-1) x min(-1) dopexamine further increased CO to 8.4 +/- 2.7 L/min (P < 0.01) without alterations of Q(S)/Q(T), perfusion of low V(A)/Q areas, and Pao2. We concluded that dopexamine (1.0 microg x kg(-1) x min(-1) and 2.0 microg x kg(-1) x min(-1)) has no adverse effects on V(A)/Q relationships and Q(S)/Q(T) in anesthetized, paralyzed patients. IMPLICATIONS: The I.V. administration of vasoactive drugs can improve oxygen delivery to different organ systems but may impair pulmonary gas exchange. In anesthetized, paralyzed patients, we studied the effects of beta2-adrenoceptor and DA1-receptor agonist dopexamine on ventilation perfusion distribution. Dopexamine (1.0 microg x kg(-1) x min(-1) and 2.0 microg x kg(-1) min(-1)) improved cardiac output and oxygenation without alterations of intrapulmonary shunt.

Adrenergic beta-Agonists↗
PubMed1998

Thoracoscopic interruption of patent ductus arteriosus compromises cardiopulmonary function in newborn pigs.

UNLABELLED: Interruption of patent ductus arteriosus (PDA) using video-assisted thoracoscopic surgery (VATS) has recently been introduced into clinical practice. To study cardiovascular and pulmonary function during VATS, we treated 16 newborn pigs (weight 1421+/-44 g) with PDA with conventional surgical interruption (CSI; n = 7) or interruption via VATS (n = 9). Measurements of hemodynamics and gas exchange were performed before, during, and after surgery. Systemic perfusion was calculated using Fick's equation. Stress hormones (ACTH, epinephrine, and norepinephrine) were determined before and after surgery. The duration of the surgical procedure was 41+/-8 min for CSI and 49+/-9 min for VATS (mean+/-SEM). With VATS, PaO2 decreased during and after surgery (P < 0.05), whereas alveolar-arterial PO2 difference (PA-aO2) and PaCO2 were increased (P < 0.05). Compared with CSI after surgery, PaO2 with VATS was decreased (130+/-10 vs 171+/-12 mm Hg; P < 0.05). Systemic perfusion was lower during VATS (76.7% of baseline) than during CSI (107% of baseline; P < 0.05). Heart rate, mean arterial pressure, and right ventricular end-diastolic pressure remained unchanged with both treatments. Stress hormones were comparable between groups. We conclude that systemic perfusion and oxygenation were impaired during VATS compared with CSI. Therefore, VATS may be contraindicated in pediatric patients with minor cardiopulmonary reserve. IMPLICATIONS: We studied the cardiopulmonary effects of endoscopic interruption of the patent ductus arteriosus in an animal model of newborn pigs. Gas exchange and systemic perfusion were impaired compared with conventional interruption of the patent ductus arteriosus after thoracotomy.

Animals↗
PubMed1998

Atelectasis and gas exchange after cardiac surgery.

BACKGROUND: Sometimes a high intrapulmonary shunt occurs after cardiac surgery, and impairment of lung function and oxygenation can persist for 1 week after operation. Animal studies have shown that postoperative shunt can be explained by atelectasis. In this study the authors tried to determine if atelectasis can explain shunt in patients who have had cardiac surgery. METHODS: Nine patients having coronary artery bypass graft surgery and nine patients having mitral valve surgery were examined using the multiple inert gas elimination technique before and after operation. On the first postoperative day, computed tomography scans were made at three levels of the thorax. RESULTS: Before anesthesia, the average shunt was low (2+/-3%; range, 0-13%), but on the first postoperative day shunt had increased to 12+/-60% (range, 3-28%). The computed tomography scans showed bilateral dependent densities in all patients but one. The mean area of the densities was 8+/-8% (range, 0-37%) of total lung area, corresponding to a calculated fraction of collapsed lung tissue of 20+/-14% (range, 0-59%). In the basal region, the calculated amount of collapsed tissue was 28+/-19% (range, 0-73%). One mitral valve patient was an outlier and had a large shunt both before and after the operation. CONCLUSIONS: Large atelectasis in the dorsal part of the lungs was found on the first postoperative day after cardiac surgery. However, there was no clear correlation between atelectasis and measured shunt fraction.

Aged↗