[Conflict matrix : Risk management tool in the operating room]. / Konfliktmatrix : Instrument des Risikomanagements im Operationssaal.

BACKGROUND: In business conflicts have long been known to have a negative effect on costs and team performance. In medicine this aspect has been widely neglected, especially when optimizing processes for operating room (OR) management. In the multidisciplinary setting of OR management, shortcomings in rules for decision making and lack of communication result in members perceiving themselves as competitors in the patient's environment rather than acting as art of a multiprofessional team. This inevitably leads to the emergence and escalation of conflicts. OBJECTIVE: We developed a conflict matrix to provide an inexpensive and objective way for evaluating the level of escalation of conflicts in a multiprofessional working environment, such as an OR. MATERIAL AND METHODS: The senior members of all involved disciplines were asked to estimate the level of conflict escalation between the individual professional groups on a scale of 0-9. By aggregating the response data, an overview of the conflict matrix within this OR section was created. RESULTS: No feedback was received from 1 of the 11 contacted occupational groups. By color coding the median, minimum and maximum values of the retrieved data, an intuitive overview of the escalation levels of conflict could be provided. The value range of all feedbacks was between 0 and 6. Estimation of the escalation levels differed widely within one category, showing a range of up to 6 (out of 6) levels. CONCLUSION: The presented assessment using a conflict matrix is a simple and cost-effective method to assess the conflict landscape, especially in multidisciplinary environments, such as OR management. The chance of conflict prevention or the early recognition of existing conflicts represents an enormous potential for cost and risk saving and might have positive long-term effects by building a culture of conflict prevention at the workplace and a positive influence on interdisciplinary cooperation in this working environment.

[Form and extent of informed consent on anesthesia risks: evaluation of a survey of all legal experts in Austria]. / Art und Umfang der Anästhesierisikoaufklärung: Auswertung einer Befragung aller Gerichtssachverständigen in Österreich.

BACKGROUND: Statistically, the chance of a patient to win a court case because of a legally insufficient informed consent is approximately 70%. In Austria the judgment whether the anesthesia-related risk of a patient was correctly addressed depends generally on the opinion of a certified expert court witness (CW). OBJECTIVES: The opinion whether well-known anesthetic risks in a commissioned court report drawn by Austrian CWs would be considered to be "typically anesthesia-related" and "needed to be addressed" when obtaining an informed consent was evaluated. MATERIALS AND METHODS: A questionnaire was sent to all Austrian CWs with 79 known anesthesia-related risks. The percentage of CWs who considered the enumerated risks as "typically anesthesia related" and "needed to be addressed" when obtaining informed consent was evaluated. RESULTS: In 32 out of 79 risks between 40% and 60% of the CWs were of the opinion that informed consent was necessary. Therefore, in a legal dispute on whether an informed consent was legally sufficient or not, the judgment of the CWs is unpredictable. In addition, due to the large number of possible complications needed to be addressed, it is not feasible to obtain a legally compliant risk disclosure. CONCLUSION: In future new methods of knowledge transfer to the patients should be developed. In addition, a standardization of the evaluation criteria for CWs in terms of improvement of legal certainty would be desirable.

[The use of oxygen as drug and its relevance for wound healing]. / Sauerstoff als Medikament und seine Bedeutung für die Wundheilung.

Plastic surgeons often have to deal with problematic wounds. In reconstructive surgery, as well as in chronic wounds, tissue oxygen supply is often critically low. Similarly in the treatment of severely burned patients, perfusion and oxygen supply to the areas beneath burn wounds are often critical. This paper explains the mechanisms and impact of oxygen for wound healing. It is important to mention that it has been shown that oxygen even used at ambient pressure can improve wound healing. Whereas treatment with oxygen under hyperbaric conditions is not everywhere available, at least normobaric oxygen is cheap and ubiquitously available and should therefore be used routinely. Oxygen treatment under hyperbaric conditions, especially in critically ill patients, needs a special infrastructure and is quite more expensive. Therefore, it has to be evaluated whether the potential benefit for the patient meets the risk and costs of treatment. In 2006, at the Hyperbaric Centre of the Medical University of Vienna almost 2200 hyperbaric treatments including 330 in critically ill patients have been performed. Beside 2 patients suffering from Fournier's gangrene, 2 suffering from gas gangrene and 4 patients with severe carbon monoxide intoxications, all other intensive-care patients were treated for severe burns. Indications for less severely ill patients mainly included problem wounds mostly of diabetic patients, osteomyelitis of the mandible and less severe carbon monoxide poisoning. Our experience with the use of oxygen under hyperbaric conditions so far has been good enough to consider this kind of therapy at least in our centre as an option in the adjunctive treatment for the so far used indications. However, it has to be mentioned that there is still lack of prospective randomised controlled studies to introduce this kind of therapy as a level 1 indication in clinical routine.

Base deficit and lactate: early predictors of morbidity and mortality in patients with burns.

Severe burn results in severe and unique physiological changes called burn shock. Historically, resuscitation has been guided by a combination of basic laboratory values, invasive monitoring and clinical findings, but the optimal guide to the endpoint of resuscitation still remains controversial. Two hundred and eighty patients, who were admitted to our Burn Unit, were enrolled in this prospective study. Resuscitation of these patients was undertaken according to the current standard of care. Parkland formula was used as a first approximation of acquired fluid administration rates; final fluid administration was adapted in order to meet clinical needs. The aim of this study was to evaluate if plasma lactate (PL) and base deficit (BD) are useful early parameters to estimate the severity of a burn. One of the main objectives was to evaluate if BD and its changes due to fluid resuscitation adds additional information in comparison to the evaluation of PL alone. The results of this study indicate that initial PL and BD level (Day 0) are useful parameters to separate survivors from non-survivors. Moreover, an outcome predictor of shock and effective resuscitation could be defined by evaluating the changes of BD on Day 1. Normalization of the BD within 24 h is associated with a better chance of survival. One explanation for this phenomenon might be the fact that many burn patients are still sub-optimally resuscitated; in summary, measuring PL and BD may help to identify critically injured patients either for enhancement of treatment, or selection of therapeutic options.

Antithrombin deficiency and its relationship to severe burns.

Antithrombin (AT) is an important endogenous anticoagulant and exhibits marked anti-inflammatory properties. To evaluate the incidence of AT deficiency in severe burn and its correlation to the variables of the abbreviated burn severity index (ABSI), length of hospital stay (LOS) and mortality we collected data on the substitution of human plasma-derived AT concentrate in 201 consecutive patients suffering from severe burn. One hundred and eight patients (54%) developed AT deficiency during their hospitalisation and, according to our institutional practice, received substitution therapy by continuous infusion to maintain physiological plasma activity (70-120%). The mean administered dose served as a measure of AT deficiency. The percentage of patients in an AT deficient state was highest within the first 5 days after injury. It was 26% on day 1 and between 38% and 41% on days 2-5 and thereafter decreased constantly over time. A multiple regression analysis between the dependent variable mean administered dose of AT concentrate and the independent variables age, total body surface area burned (TBSA), gender, inhalation injury (INHAL), full thickness burn (FTB), LOS and mortality was performed. Age, gender and FTB showed no significant influence on the development of AT deficiency. Increasing TBSA and INHAL clearly increase the risk of developing AT deficiency (p-values 0.0001 and 0.037). The analysis also identified AT deficiency as an independent predictor of LOS and mortality (p-values 0.036 and 0.003). Development of AT deficiency is a frequent event after burn with significant correlation to TBSA and INHAL, increased mortality rates and longer hospital stays.

The influence of deliberate hypotension on splanchnic perfusion balance with use of either isoflurane or esmolol and nitroglycerin.

UNLABELLED: Various techniques to induce deliberate hypotension (DH) have different influences on splanchnic perfusion. The aim of our study was to determine whether splanchnic perfusion is clinically impaired during DH by using either isoflurane (ISO) or a combination of esmolol and nitroglycerin (E/N). We randomized 16 patients undergoing elective maxillofacial surgery to receive either ISO (0.7%-1.8%) or E (105 g x kg(-1) x min(-1)) and N (1-6 mg/h) to induce DH. General anesthesia was performed in both groups by IV midazolam 0.07 mg/kg, fentanyl 0.003 mg/kg, propofol 1.5 mg/kg, and vecuronium 0.1 mg/kg followed by a propofol infusion with 6 mg x kg(-1) x h(-1). After the induction of anesthesia, a gastric tonometer (TRIP NGS Catheter) and a radial artery catheter were inserted. Baseline values of gastric intramucosal pH (pHi) were determined 60 min after placement of the catheter and before the induction of DH. The pHi values were calculated every 60 min until DH was discontinued. In both groups, DH was satisfactorily established. None of the pHi values calculated was less than 7.37 in the E/N or 7.41 in the ISO group. Arterial blood lactate levels did not increase in any of the patients. We conclude that neither method of producing DH compromises splanchnic tissue oxygen balance in healthy patients. Furthermore, overall organ perfusion was sufficient in both groups, because none of the patients showed an increase in blood lactate. IMPLICATIONS: Neither the isoflurane nor the esmolol/nitroglycerin method of producing deliberate hypotension compromises splanchnic tissue oxygen balance in healthy patients. Furthermore, overall organ perfusion was sufficient in both groups, because none of the patients showed an increase in blood lactate.

Impact of early high caloric duodenal feeding on the oxygen balance of the splanchnic region after severe burn injury.

Early enteral nutrition is recommended in burned patients. Depending on the amount administered, enteral feeding causes an increase of intestinal oxygen-demand. Although early moderate enteral nutrition has been shown to be beneficial, early high calorie enteral nutrition might lead to an imbalance of the O(2)-balance of the gut since intestinal perfusion is decreased after major burns. In 20 severely burned patients during the first 48 h of early high caloric duodenal feeding an assessment of the CO(2)-gap between the arterial and the gastric CO(2), as parameter for the intestinal O(2)-balance, was performed. Time points were prior to starting the enteral nutrition (BASE) subsequently every 30 min after increasing the amount of nutrition administered and from the 11th to the 48th h after beginning of nutrition in intervals of 6 h. In none of the patients was the CO(2)-gap increased during the rapid increase of enteral nutrition. On the contrary the CO(2)-gap decreased significantly. We conclude that high caloric duodenal feeding in the early hypodynamic postburn phase does not have adverse effects on the oxygen balance of the intestine.

Propofol without muscle relaxants for conventional or fiberoptic nasotracheal intubation: a dose-finding study.

UNLABELLED: Endotracheal intubation has been performed during the administration of propofol anesthesia without neuromuscular blockade. In this study, we determined the propofol dose required for conventional nasotracheal or for fiberoptic nasotracheal intubation of all patients. Thirty-two patients undergoing maxillofacial surgery were randomly assigned to the conventional (n = 16) or to the fiberoptic (n = 16) intubation group. In both groups, anesthesia was induced by using IV fentanyl and IV titrated propofol according to clinical need (spontaneous respiration rate, verbal response). An endotracheal tube was placed nasally in the pharynx and the vocal cords visualized by using a fiberscope inserted via the tube. In the conventional group, the larynx was visualized additionally with a laryngoscope blade (Miller). In both groups propofol was titrated until the vocal cords opened. Patients were tracheally intubated, and the propofol dose was recorded. In all patients, the trachea could be intubated without the use of muscle relaxants. Considerable interindividual differences of dose requirements were observed. The amount of propofol required in the conventional group was significantly (P < 0.0001) larger (median +/- SD: 2.74 +/- 1.59 mg/kg; range 1.95-7.07 mg/kg) than in the fiberoptic group (1.37 +/- 0.59 mg/kg; 0.72-2.86 mg/kg). Hemodynamics remained stable in all patients. Postintubational hoarseness occurred in three patients of each group. Fiberoptic nasal intubation without a muscle relaxant can be facilitated with significantly smaller and more predictable dosages of propofol than conventional nasal endotracheal intubation. The possibility of titrating the propofol dose under assisted ventilation until the vocal cords open during fiberoptic nasotracheal intubation and the better predictability of the required dose favors the fiberoptic approach. IMPLICATIONS: In this study, contrary to all preceding studies using predefined doses of propofol and opioids, we determined the minimal required propofol dose in combination with fentanyl for conventional or fiberoptic nasotracheal intubation without muscle relaxants.

zfNLRR, a novel leucine-rich repeat protein is preferentially expressed during regeneration in zebrafish.

zfNLRR is a novel transmembrane protein that is most prominently expressed during regeneration of the zebrafish central nervous system. Retinal ganglion cells and descending spinal cord neurons strongly increase zfNLRR mRNA levels after axotomy in the adult. In contrast, during development expression is hardly detectable and is restricted to a few sensory systems. In the adult brain, zfNLRR mRNA is found at low levels in several motor and premotor systems. Sequence analysis reveals that zfNLRR contains in its extracellular region 12 leucine-rich repeats, 1 immunoglobulin-like domain and 1 fibronectin type III-like domain. The same protein binding motifs were identified in transmembrane proteins from frog, mouse, and human. Together, they constitute a novel family of vertebrate neuronal leucine-rich repeat proteins. Three distinct isoforms are identified so far. On the basis of its structural features and expression pattern, we propose that zfNLRR functions as a neuronal-specific adhesion molecule or soluble ligand binding receptor, primarily during restoration of the nervous system after injury.

The axillary vein central venous catheter in severely burned patients.

In severely burned patients the approach to the central vein is often difficult due to concomitant edema, but also due to the fact that the skin area, where commonly used approaches are performed, is burned as well, whereas the axillary region is often not involved. In order to perform an axillary approach to the central vein as an alternative to the commonly used approaches in patients, an anatomical dissection in fresh human cadavers was carried out. Considering the anatomical landmarks which were found during dissection of the axillary region, the axillary approach to the central vein was used in 35 patients in our intensive burn care unit with unaffected axillary skin. In three cases the only complication observed was an occasional puncture of the axillary artery without major hematoma. The infection rate of the catheters was similar to the commonly used puncture sites. This approach to the central venous line in severely burned patients can be recommended.