[Post-mortem organ donation]. / Postmortale Organspende.

In Germany approximately 3000 body organs are transplanted annually. In general, all artificially ventilated patients with diagnosed brain death are potential organ donors. All German hospitals are obliged to report potential organ donors and be actively involved in the organ donation process. These matters lie under the jurisdiction of the German transplantation act. An essential prerequisite for organ donation is the diagnosis of brain death according to the guidelines of the German Medical Association. Brain death is associated with complex pathophysiological changes in cardiopulmonary function as well as fluid, electrolyte and metabolic homeostasis. In the case of diagnosed brain death and with permission for organ donation, a precise organ-protective therapy is initiated, essentially focussing on optimal organ perfusion and oxygenation. The quality of organ protection has a direct influence on the outcome of transplantation.

[Quality of anesthesiological expert opinion in medical claims cases]. / Qualität anästhesiologischer Gutachten bei medizinischen Schadensfällen.

Expert opinions have an important place for expert testimony in medical disputes. The report should contain a summary about facts and causality between the damage and the medical treatment in question as well as describe the current medical standard. The fulfillment of scientific criteria was investigated in 179 anesthesiological expert opinions from 150 arbitration cases. Anesthesiological expert reports (2005-2007) of the Arbitration Board of the North German Medical Associations were analyzed in terms of structure, general form of assessment and scientific substantiation of statements. Patient damage was confirmed in 76%, treatment failure in 29% and negligent malpractice in 17% of the reports. In 78% of the reports the facts were presented correctly and in 64% the question was answered whether the incident would have occurred even during adequate and professional action. Conclusive statements about the causality between the damage and the medical treatment in question were available only in 60% of the reports. The study findings suggest that anesthesia expert reports present a high incidence of non-scientific claims. The development of guidelines for expert witnesses by the medical societies is urgently recommended.

[Base excess. Parameter with exceptional clinical significance]. / "Base excess". Parameter mit herausragender klinischer Bedeutung.

The base excess of blood (BE) plays an important role in the description of the acid-base status of a patient and is gaining in clinical interest. Apart from the Quick test, the age, the injury severity score and the Glasgow coma scale, the BE is becoming more and more important to identify, e. g. the risk of mortality for patients with multiple injuries. According to Zander the BE is calculated using the pH, pCO(2), haemoglobin concentration and the oxygen saturation of haemoglobin (sO(2)). The use of sO(2 )allows the blood gas analyser to determine only one value of BE, independent of the type of blood sample analyzed: arterial, mixed venous or venous. The BE and measurement of the lactate concentration (cLac) play an important role in diagnosing critically ill patients. In general, the change in BE corresponds to the change in cLac. If DeltaBE is smaller than DeltacLac the reason could be therapy with HCO(3)(-) but also with infusion solutions containing lactate. Physician are very familiar with the term BE, therefore, knowledge about an alkalizing or acidifying effect of an infusion solution would be very helpful in the treatment of patients, especially critically ill patients. Unfortunately, at present the description of an infusion solution with respect to BE has not yet been accepted by the manufacturers.

[Injuries in anaesthesia. Results of the Hannover arbitration procedure 2001-2005]. / Schäden in der Anästhesie. Ergebnisse der Hannoverschen Schlichtungsverfahren 2001-2005.

The Schlichtungsstelle in Hannover (expert panel for arbitration), northern Germany, was founded in 1976 to settle disputes between patients and doctors. Furthermore, publications regarding the decisions of the Schlichtungsstelle serve as an important medium to prevent malpractice by increasing doctors' awareness of critical processes in their field. Between 2001 and 2005 the Schlichtungsstelle decided on 435 malpractice claims in anaesthesia. An accumulation of injuries was observed in anaesthetic procedures with respect to the airways (23.9%), injuries related to regional anaesthesia (18.2%), vasopuncture (13.1%) and positioning of the patients (9.9%). In 21.8%, the Schlichtungsstelle advised to seek a resolution without going to court by paying financial compensation in favour of the patient. In these cases the Schlichtungsstelle's evaluation had come to the conclusion that malpractice was the cause of the patient's injury. We would like to mention that 21 cases of intraoperative awareness were included in the claims, of which 52.4% (average 21.8%) were evaluated to be the result of malpractice and thus financial compensation was advised. The appropriate care for the patient, required from every doctor, calls the anaesthesiologists to avoid all possible malpractices, thus reducing patients' injury due to such malpractices to a minimum. But even injuries not caused by malpractice need to be examined closely and improvement should be sought.

[Loss of vision after non-ophthalmic surgery: systematic review of the literature on incidence, pathogenesis, treatment and prevention]. / Erblindung nach nichtophthalmologischen Eingriffen : Systematische Literaturübersicht zu Inzidenz, Pathogenese, Behandlung und Prävention.

BACKGROUND AND GOAL: Postoperative loss of vision is a rare, but devastating complication after non-ocular surgery. It can occur partially or completely and may involve one or both eyes. Since its etiology has not yet been solved, the purpose of this review was to extract potential causes from the case collections reported to propose prophylactic measures. METHODS: A literature search was performed using the "Pubmed" database of the US National Library of Medicine. MeSH terms and combinations used were: blindness, postoperative complications, ischemic optic neuropathy, not ophthalmological surgical procedures, not neurosurgical procedures. Additionally, the results of the interim analysis of the postoperative visual loss (POVL) registry of the ASA were considered. RESULTS: The incidence of permanent loss of vision after non-ophthalmologic surgery is reported to be 0.0008%. However, it is elevated up to 0.11% after cardiac and 0.08% after spine surgery. Risk factors seem to be perioperative anemia, arterial hypotension and prone position, but also pre-existing diseases such as arteriosclerosis. Thus hemodynamic stabilization or correction of anemia may be successful in therapy. CONCLUSION: Patients with pre-existing arteriosclerotic disease scheduled for spine or cardiac surgery, but also for bilateral neck dissection should be informed preoperatively about the rare possibility of POVL. Postoperatively any visual changes should be immediately referred to an ophthalmologist and treated accordingly.

Point-of-care testing apparatus. Measurement of coagulation.

Point-of-care testing of coagulation parameters provides a more rapid assessment of test results compared with laboratory testing. A new coagulation monitor (GEM PCL, Instrumentation Laboratory, Kirchheim, Germany) was evaluated. Point-of-care data for activated partial thromboplastin time and prothrombin time (expressed as the international normalised ratio) and turn-around-time were compared. Coagulation parameters were compared in the blood of 57 patients with and without heparin therapy. The point-of-care and laboratory test results showed a bias (SD) of -0.26 (4.55) s for activated partial thromboplastin time and -0.011 (0.150) s for prothrombin time. The average turn-around-time was 3 min for point-of-care testing vs. 52 min for laboratory testing. We conclude that the reliability of point-of-care testing is sufficient for clinical use.

Preoxygenation: a comparison of three different breathing systems.

An end-tidal expiratory oxygen concentration (FE'O2) greater than 0.90 is considered to be adequate for preoxygenation. This is generally achieved using a face mask, but this can be unsatisfactory in some patients. We compared preoxygenation in 30 healthy volunteers using a face mask, the NasOral system, which is a novel preoxygenation device, and a mouthpiece with a nose-clip. We measured the maximal FE'O2, the FE'O2 after 2 min and the time to reach maximal FE'O2 and recorded the subjective judgement of the volunteers. The maximal FE'O2 with face mask and mouthpiece was significantly greater than with the modified NasOral system (P<0.05 and P<0.01). With the former devices, a FE'O2 of 0.90 was achieved in 73% of the volunteers vs 46% with the modified NasOral system. Using the mouthpiece, the FE'O2 after 2 min was significantly higher than using the face mask (P<0.01) or the modified NasOral system (P<0.01). The time to maximal FE'O2 was significantly shorter using the modified NasOral system than with the face mask or mouthpiece (P<0.001 and P=0.0001). The volunteers gave more positive ratings to the face mask and mouthpiece than to the modified NasOral system (P<0.001 and P<0.01). We conclude that the use of a mouthpiece can improve preoxygenation in some patients. The results obtained with the modified NasOral system do not justify its introduction into clinical practice.

Hearing loss after spinal and general anesthesia: A comparative study.

Hearing loss has been described after spinal anesthesia. We examined the hearing in patients before and after spinal and general anesthesia by pure tone audiometry (LdB: 125-1500 Hz; HdB: 2000-8000 Hz). Tympanic membrane displacement analysis was used to noninvasively monitor the intralabyrinthine and intracranial pressure. Eighteen patients received spinal anesthesia (G(SA)); 19 patients general anesthesia (G(GA)). Pure tone audiometry and TMD data were obtained preoperatively ((0)) and postoperatively on day 1 ((1)) and 2 ((2)). The mean threshold differences (Delta) in LdB(10) and LdB(20) were significantly different in G(SA) compared with G(GA) (DeltaLdB(10) + 0.15+/-3.07 dB vs. -1.34+/-3.77 dB, P = 0.05; DeltaLdB(20) -0.54+/-2.24 dB vs. -2.45+/-3.39 dB, P<0.01). However, there were no differences in DeltaHdB(10) between G(SA) and G(GA), but in DeltaHdB(20) (-1.40+/-3.95 dB vs -5.12+/- 6.35 dB, P = <0.01). We found a significant correlation between the magnitude of intraoperative intravascular volume replacement and low-frequency hearing loss. Tympanic membrane displacement values were not different pre- and postoperatively. Hearing was impaired after spinal and general anesthesia. Low-frequency hearing loss was correlated with intraoperative volume replacement. Tympanic membrane recordings did not reveal significant changes.

Unilateral lung edema: effects on pulmonary gas exchange, hemodynamics, and pulmonary perfusion distribution.

Two types of unilateral lung edema in sheep were characterized regarding their effects on pulmonary gas exchange, hemodynamics, and distribution of pulmonary perfusion. One edema type was induced with aerosolized HCl (0.15 M, pH 1.0) and the other with NaCl (0.15 M, pH 7.4). Both aerosols were nebulized continuously for 4 h into left lungs. In HCl-treated animals, pulmonary gas exchange deteriorated [from a partial arterial O(2) pressure-to-inspired O(2) fraction ratio (Pa(O(2))/FI(O(2))) of 254 at baseline to 187 after 4 h HCl]. In addition, pulmonary artery pressure and total pulmonary vascular resistance increased (from 16 to 19 mmHg and from 133 to 154 dyn. s. cm(-5), respectively). In NaCl-treated animals, only the central venous pressure significantly increased (from 7 to 9 mmHg). Distribution of pulmonary perfusion (measured with fluorescent microspheres) changed differently in both groups. After HCl application, 6% more blood flow was directed to the treated lung, whereas, after NaCl, 5% more blood flow was directed to the untreated lung. HCl and NaCl treatment both induce an equivalent lung edema, but only HCl treatment is associated with gas exchange alteration and tissue damage. Redistribution of pulmonary perfusion maintains gas exchange during NaCl treatment and decreases it during HCl inhalation.

Different dosages of dobutamine in septic shock patients: determining oxygen consumption with a metabolic monitor integrated in a ventilator.

OBJECTIVE: Oxygen consumption (VO2) obtained from respiratory gases by indirect calorimetry (VO2,IC) with a metabolic monitor integrated in a ventilator were to be compared to VO2 obtained by the Fick principle (VO2,Fick) in septic patients following an increase in oxygen delivery (DO2) induced by positive inotropic support. DESIGN: Prospective clinical study. SETTING: University Hospital, Surgical Intensive Care Unit (ICU). PATIENTS: Thirty patients suffering from sepsis. INTERVENTIONS: DO2 was increased by dobutamine infusion, starting with an initial dosage of 5 microg x kg x min, increased to a maximum of 10 microg x kg x min. MEASUREMENTS AND MAIN RESULTS: Dobutamine infusion induced a dosage-related increase in DO2 (from 577 +/- 192 to 752 +/- 202 ml x min x m2, p < 0.01), which was associated with a statistically significant increase in VO2,IC (from 173 +/- 30 to 188 +/- 28 ml x min x m2, p < 0.01) and in VO2,Fick (from 140 +/- 25 to 156 +/- 24 ml x min x m2, p < 0.01). The comparison between VO2,IC and VO2,Fick revealed differences (bias and precision--33 +/- 32 ml x min x m2). CONCLUSIONS: With a metabolic monitor integrated in a ventilator it was possible to carry out continuous monitoring of calorimetric data under clinical conditions. In contrast to previous studies using indirect calorimetry, this study showed a moderate correlation between VO2 and DO2 in septic patients using either method. The clinical relevance of this finding requires further investigation. Different factors (e. g. injectant temperature, pulmonary VO2) produced substantial differences between VO2,IC and VO2,Fick as previously shown.

Effect of profound normovolemic hypotension and moderate hypothermia on circulating cytokines and adhesion molecules.

Hypotension caused by hypovolemic, hemorrhagic shock induces disturbances in the immune system that may contribute to an increased susceptibility to sepsis. The effect of chemically induced hypotension on circulating cytokines and adhesion molecules has not been investigated yet. In 21 patients scheduled for resection of malignant choroidal melanoma of the eye the perioperative serum levels of the cytokines IL-1beta, IL-6, IL-10, TNF-alpha, and the adhesion molecules sE-Selectin and sICAM-1 were investigated. Moderate hypothermia of 32 degrees C was induced in all patients. In 14 patients profound hypotension (mean arterial blood pressure 35-40 mmHg, hypotension group) was induced by enalapril and nitroglycerin for a mean duration of 71 min. In 7 patients the tumor was not resectable, and hypotension was not induced (controls). We did not detect significant differences in serum levels of cytokines or sE-Selectin perioperatively in patients with profound hypotension compared with controls. In both groups IL-6 serum levels increased significantly and reached a maximum after rewarming (17 +/- 6 and 16 +/- 5 pg/dL, respectively, P < 0.001). IL-1beta, IL-10, and TNF-alpha did not change perioperatively in both groups. On the first postoperative day sICAM-1 serum levels were significantly increased in both groups (mean increase of 96 and 54 ng/mL, respectively, P < 0.01 and P < 0.05). We conclude from this study that profound normovolemic arterial hypotension does not seem to have effects on serum levels of circulating IL-1beta, IL-6, IL-10, TNF-alpha, and sE-Selectin. Perioperative moderate hypothermia may be the reason for the postoperative increase in sICAM-1 levels independent of the blood pressure.

Serum cardiac troponin T as a prognostic marker in early sepsis.

STUDY OBJECTIVE: Sepsis is the leading cause of death in the noncardiologic ICU. Maldistributed nutritive blood flow and altered convective and diffusive oxygen transport during sepsis can lead to organ dysfunction and multiple organ failure. One of the causes of myocardial dysfunction is thought to be myocardial ischemia in sepsis; however, conventional biochemical parameters to detect myocardial ischemia lack sensitivity and specificity. Serum cardiac troponin T (S-TnT) was reported to have higher sensitivity and specificity in diagnosing minor myocardial injury. The aim of this study was to investigate if and how often S-TnT is pathologically elevated in patients with sepsis and to evaluate whether S-TnT might be a prognostic marker in early sepsis. DESIGN: Prospective study. SETTING: Surgical ICU. PATIENTS: Twenty-six patients with sepsis were included in this study within 24 h of the onset of sepsis. The patients were allocated a priori to a high S-TnT group (S-TnT > or = 0.2 microg/L) and a low S-TnT group (S-TnT<0.2 microg/L). MEASUREMENT: Blood samples for the determination of S-TnT and conventional myocardial ischemia markers as well as for adhesion molecules were drawn. Hemodynamic measurements were performed every 4 h during the first 24 h and then once per day over 7 days. S-TnT was determined by enzyme-linked immunosorbent sandwich assay. RESULTS: Eighteen patients had pathologically high S-TnT values. High S-TnT values were associated with an increased mortality rate (15/18 in the high S-TnT group vs 3/8 in the low S-TnT group; p=0.02). Significant differences between the two groups were found in the norepinephrine dosages at maximum values of S-TnT. Soluble intercellular adhesion molecule-1 was significantly elevated in the high S-TnT group. CONCLUSIONS: As high S-TnT values were associated with an increased mortality rate, it seems reasonable to further evaluate S-TnT as a prognostic marker of myocardial ischemia in patients with sepsis under different therapeutic regimens.

Halothane-propofol anaesthesia for tracheal intubation in young children.

In this double-blind, randomized study, we have investigated 100 healthy children, aged 3-6 yr. We compared intubating conditions and cardiovascular changes during light halothane anaesthesia and propofol 3 mg kg-1 with those during deep halothane anaesthesia. Light halothane anaesthesia was defined as an end-tidal concentration of 1%, deep halothane anaesthesia as 2%. Intubating conditions were graded according to ease of laryngoscopy, vocal cord position and coughing. There were no statistically significant differences in the assessment of intubating conditions between the two groups; 94% of the children in the 1% halothane-propofol group and 100% of the children in the 2% halothane group had acceptable intubating conditions. Systolic arterial pressure decreased by 13% in the 1% halothane-propofol group compared with 20% in the 2% halothane group (P < 0.01).

Deep halothane anaesthesia compared with halothane-suxamethonium anaesthesia for tracheal intubation in young children.

A double-blind and randomized study design was used to investigate 100 healthy children, aged 1-5 years. Intubating conditions and cardiovascular changes during deep halothane anaesthesia, defined as an end-tidal concentration of 2%, were compared with those changes during 1% halothane and suxamethonium relaxation. Intubating conditions were graded according to the ease of laryngoscopy, vocal cord position, coughing and jaw relaxation. In each group 96% of the children demonstrated acceptable intubating conditions. Jaw relaxation was worse in the 1% halothane/-suxamethonium group (P < 0.01). When anaesthesia with 2% or 1% halothane was compared there was a more pronounced decrease in systolic blood pressure (18 vs. 8%, P < 0.001). Junctional rhythm occurred more frequently during deep halothane anaesthesia (46 vs. 18%, P < 0.01). Intravenously (i.v.) administered atropine attenuated blood pressure depression significantly and reinstituted sinus rhythm in most cases.