Perioperative Anämie

Anemia is a frequent finding, particularly in the elderly population, and usually indicative of a serious disease. The main causes of preoperative anemia are acute or chronic hemorrhage, iron deficiency, renal insufficiency, inflammatory and neoplastic diseases. A preexisting mild anemia may be enhanced or unmasked by surgically induced bleeding or repeated diagnostic phlebotomies, and by a postoperative erythropoietic dysfunction caused by the surgical trauma, irrespective of any hemorrhage. Low hemoglobin values are associated with a distinct increase of mortality and morbidity, both in the normal population and perioperatively and in the critically ill patients. The anemia-associated risk is exacerbated by preexisting cardiovascular disease, important intraoperative blood loss and advanced age. In contradiction to established therapeutical concepts, the administration of allogeneic blood beyond hemoglobin levels of 8-10 g/dl has not been found to decrease perioperative or intensive care morbidity or mortality. Rather, in addition to the inherent long-term risks of transfusions, a liberal transfusion strategy seems to increase the incidence of postoperative complications. Thus, current transfusion guidelines tend to be interpreted in an increasingly restrictive manner. Depending on the urgency of the clinical situation, the primary goal should be to diagnose and treat the underlying disease, rather than to focus on the symptom anemia. Time permitting, the patient's cardiovascular and pulmonary status should be optimized preoperatively. Furthermore, iron should be substituted to treat and prevent deficiency. Recombinant human erythropoietin has successfully been used to treat anemia of chronic renal failure and chronic disease, as well as in the perioperative and intensive care setting, and to support the efficiency of autologous programs.     

Herzfrequenzabhängige EKG-Veränderungen bei einem Patienten mit schwerer Sichelzellanämie

Die Anaesthesiologie -     

Überwachung des Behandlungserfolgs der bei Kalziumoxalatsteinmetaphylaxe mit dem Bonn-Risk-Index

Cost-effective metaphylaxis and monitoring is becoming more and more focused in the treatment of urinary stones. Therefore, medical practitioners are asked to reduce the analytical efforts necessary for evaluation and to control the actual biochemical risk of stone formation in the patients. The most common strategy available is based on chemical urinalysis and the calculation of theoretically derived risk parameters. However, this covers--in the best case--the analysis of the most prominent low molecular urinary constituents. No information about the fraction of the important macromolecular urinary components is obtained. Crystallization experiments in unprepared, native urine samples, carried out according to the Bonn-Risk-Index approach (BRI), allow the determination of a more realistic measure of a urine's crystallization risk since the entire urinary composition influences the experimental result. As only two parameters have to be analyzed, the BRI is a fast and cost-effective risk evaluation method. The results show a high selectivity between stone-formers and non-stone-forming persons. The changes in the BRI-risk of three calcium oxalate stone-formers after a 1 week stay in our hospital are presented and discussed in detail. In one of these patients, a follow up examination was performed in order to control the therapy's success and, additionally, to obtain information about the patient's compliance with the therapy. During hospitalization, the patients received a standardized and "stone-neutral" diet. All persons showed a distinct decrease in their individual crystallization risk.     

Über die Anwendung der Suprareninanämie bei Operationen am Schädel und der Wirbelsäule

Ohne Zusammenfassung (Mit 4 Abbildungen.)     

Perioperative Antibiotikaprophylaxe bei aseptischen Eingriffen in der Orthopädie

Disagreement exists on the topic of antibiotic prophylaxis in aseptic orthopedic surgery. No evidence on the usefulness of prophylactic antibiotic administration exists with regard to non-complex aseptic surgeries without placement of osteosynthetic material. Likewise, no undisputed evidence exists on the usefulness of antibiotic prophylaxis with regard to aseptic orthopedic surgeries involving placement of osteosynthetic material. However, the majority of experts agree on antibiotic prophylaxis in the latter cases. In contrast clear evidence does exist regarding the usefulness of antibiotic prophylaxis with first- or second-generation cephalosporins for surgeries of the hip involving fracture treatment or prosthetic replacement. The prophylactic use of glycopeptides should be confined to cases of high MRSA or MRSE risk. Administration of prophylactic antibiotics should precede incision time by around 30 min and tourniquet inflation by at least 10 min. Antibiotic administration may be repeated in the OR when surgery lasts longer than 3 h. The use of local antibiotics in bone cement has not proven useful as a prophylactic measure.     

Die Bedeutung der Toxämie bei der operativen Kollapstherapie der Lungentuberkulose

Zusammenfassung Im Anschlu? an die Thorakoplastik treten bei zahlreichen Lungentuberkul?sen vorübergehend Fernsymptome auf, die vermutlich durch Toxine hervorgerufen werden. Die gleichen Erscheinungen sind gelegent lich bei florider Lungentuberkulose, besonders in deren Anfangstadien und nach Einspritzung relativ hoher Tuberkulindosen, beobachtet worden. Diese Erscheinungen betreffen vorwiegend solche Kranke, die im postoperativen Stadium spezifisch entzündliche Komplikationen aufweisen; zeitlich treten sie meist mit diesen zusammen auf. Kein wesentlicher Zusammenhang der postoperativen Kreislauffunktion mit den toxischen Fernsymptomen. Bei Lungentuberkul?sen fand sich in 15% vor der Operation, in 20% nach der Thorakoplastik kulturell Bacill?mie. Keine Abh?ngigkeit der toxischen Erscheinungen von der Bacill?mie. Die Tuberkulinallergie nimmt im allgemeinen nach der Thorakoplastik ab. Besonders deutlich ist die Abnahme bei Kranken, deren postoperativer Verlauf durch schwere entzündliche Erscheinungen kompliziert ist. Diese Kranken sind auch vorwiegend an manifesten toxischen Symptomen beteiligt. Der postoperative Allergiesturz kann als prognostisch ungünstig gewertet werden.      

Hemikolektomie bei Kolonischämie

Pandemic influenza A (H1N1) virus infection is rapidly spreading and has also become a common problem in Germany. Many cases with severe clinical presentation and death have been documented, especially in persons with underlying medical conditions. As of December 15, 2009, Germany has reported 119 H1N1-associated deaths. We report here the first H1N1-associated death in Germany, a 36-year-old woman with morbid obesity. The patient underwent a laparotomy with colon resection due to colon ischemia, a rare visceral complication in such cases. In this article an attempt has been made to reflect the state of requirements in terms of safety, occupational health, hygiene and working conditions with respect to activities involving logistics in the diagnostics, treatment (also surgical) and handling of such patients. Given the rapidly evolving nature the outbreak of human infection with the novel influenza A (H1N1) virus, influenza vaccination is recommended as the only way to prevent the infection of health care workers and patients with underlying medical conditions.     

Wertigkeit der perkutanen Aspirationsthrombektomie (PAT) bei der Behandlung der akuten Extremitätenischämie

Background

An acute embolic or thrombotic occlusion of a lower limb can be primarily treated by conventional operative or catheter-based techniques. Experience with percutaneous catheter aspiration thrombectomy (PAT) is limited. The aim of this study was to report the early and midterm results of PAT in the treatment of acute lower limb ischemia (ALI).

Patients and methods

An evaluation and review of all consecutive patients who underwent PAT for treatment of ALI between January and December 2008 were carried out. The primary endpoints were clinical success and limb salvage rates at 30 days and 19 months follow-up. Secondary endpoints included complications, midterm patency and mortality rates.

Results

A total of 24 patients were included in the study. Complete thrombus removal was achieved in 19 patients (79?%). Additional therapy included angioplasty and stent (n?=?3, 12?%) and catheter directed thrombolysis (CDT) (n?=?2, 8?%). In five patients (21?%) PAT failed and transpopliteal embolectomy (n?=?4) or CDT (n?=?1) was performed. The limb salvage rate was 100?% at 30 days and 96?% at 19 months follow-up. The survival rate was 100?% at 30 days and 88?% at 19 months. The cumulative primary patency, assisted primary patency and secondary patency rates were 71 %, 79 % and 96?%, respectively at 19 months follow-up. Early complications occurred in three patients (12?%) including two groin hematomas and bleeding and one compartment syndrome after CDT. All complications required surgery. The mean time of PAT was 136 min (range 30–342 min).

Conclusion

The results show that PAT is an effective treatment option with excellent short and midterm results in patients with ALI. The complication and mortality rates are very low. Although PAT can be time-consuming, it is an important therapeutic option for patients with good renal function, clinically compensated ischemia and palpable groin pulse.     

Perioperative Myokardschäden bei nichtkardiochirurgischen Patienten

Perioperative myocardial damage occurs with a high incidence depending on the operative procedure and the patients examined and is considered to be among the most relevant risk factors for increased perioperative morbidity and mortality in patients undergoing non-cardiac surgery. The pathophysiology of myocardial damage in the perioperative period is still not well understood. Both ischemia with and without acute coronary occlusion and non-ischemic stimuli can put a substantial strain on the heart in the perioperative period. However, in many cases the clinical presentation does not allow a clear differentiation between ischemic and non-ischemic myocardial damage. In the majority of cases perioperative myocardial infarctions occur with only mild or even without any clinical symptoms. This is probably due to a considerable difference in phenotype and pathophysiology between perioperative and non-perioperative myocardial infarctions. As a result of this unexplained etiology of perioperative myocardial infarction it remains an open question whether the contemporary diagnostic and therapeutic recommendations for the acute coronary syndrome can be extrapolated to the perioperative situation. The present review reflects the current state of knowledge and presents an optional approach to the diagnosis and therapy of perioperative myocardial injury.     

Ergebnisse der peripheren Bypasschirurgie bei Patienten mit kritischer Extremitätenischämie

Aim

The outcomes of patients with critical limb ischemia (CLI) who underwent lower extremity bypass surgery were analyzed based on the data in the CRITISCH registry with respect to the localization of the distal anastomosis and type of bypass material.

Patients and methods

In total 284 patients with a lower extremity bypass (group 1: 75 patients with bypass above the knee, group 2: 80 patients with bypass below the knee and group 3: 129 patients with crural or pedal bypass) were included in this study. The graft material included 159 autologous saphenous vein grafts and 125 prosthetic grafts.

Results

There were no perioperative complications in 191 out of the 284 patients (67.3?%) and in 236 out of the 284 (83.1?%) patients the bypass remained open at discharge from hospital. An uneventful postoperative course was documented in 76?% of the patients in group 1, 62.5?% in group 2 and 65.1?% in group 3. The amputation-free survival at 1 year was 86?% in group 1, 65?% in group 2 and 69?% in group 3. In patients with a bypass above the knee prosthetic grafts were at least not inferior to vein grafts (amputation-free survival at 1 year: prosthetic bypasses 92?%, saphenous vein grafts 71?%, p?=?0.147), while in the group with a crural or pedal bypass, vein grafts showed a better amputation-free survival at 1 year (76?%) compared with prosthetic bypasses (56?%, p?=?0.105). Patients with a PIII CLI risk score ≤?3 exhibited a better amputation-free survival at 1 year of 78?% compared to patients with PIII CLI risk scores 4–7 with 69?% (p?=?0.053). The same applied to patients with Rutherford stage 4 versus Rutherford stage 6 CLI.

Conclusions

In patients with CLI and a bypass above the knee, vein grafts provide no benefits for at least 1 year follow-up when compared with prosthetic grafts. But in more distal anastomoses vein grafts should be preferred.

     

Perioperative Cefamandolprophylaxe bei aortocoronaren Bypass-Operationen Serumkonzentrationsverlauf während der extrakorporalen Zirkulation

Zusammenfassung Eine perioperative antibiotische Kurzprophylaxe mit 2 g Cefamandol intravenös bei Narkoseeinleitung wurde bei 12 Patienten während coronarchirurgischer Eingriffe unter Verwendung der Herz-Lungen-Maschine durchgeführt. Bei Beginn der extrakorporalen Zirkulation (= EKZ) kam es infolge Hämodilution zu einem Absinken der Serumkonzentrationen von 110,96 ± 40,29 mcg/ml auf 70,89 ± 34,65 g/ml innerhalb von 10 min. Im weiteren Verlauf der EKZ war der Abfall der Serumspiegel gleich schnell wie davor und danach. Nach 240 min fanden sich noch Serumspiegel von 16,80 ± 9,32 g/ml. Als Ursache für das Versagen einer antibiotischen Prophylaxe kommt bei einer Operationsdauer von mehr als 4 h das Absinken der Serumspiegel unter die minimale Hemmkonzentration der entsprechenden Keime in Frage.

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Perioperative cefamandole prophylaxis in aortocoronary bypass operations: Course of serum concentration during extracorporeal circulation

Summary Antibiotic prophylaxis with 2 g Cefamandole at induction of anaesthesia was performed in 12 male patients undergoing aortocoronary bypass surgery. Caused by hemodilution, there was a marked decrease of serum concentration at the beginning of extracorporeal circulation, from 110.96 ± 40.29 mcg/ml to 70.89 ± 34.65 mcg/ml within 10 min. During extracorporeal circulation, elimination was as fast as before and after perfusion. 240 min after application, mean serum concentrations of 16.80 ± 9.32 mcg/ml were measured. Failure of antibiotic prophylaxis in operations exceeding 4 h might be due to unadaequate antibiotic concentrations, beyond the minimal inhibitory concentration for the pathogens, reported to cause infections after cardiac operations.

     

Perioperative Anämie – Toleranz oder Therapie?

Ohne Zusammenfassung     

Perioperative Veränderungen der Flüssigkeitsfiltrationskapazität bei gefäßchirurgischen Patienten

Patients undergoing major vascular surgery frequently require a substantial intraoperative fluid replacement to assure hemodynamic stability, which is in excess of the expected fluid requirements due to starving, blood and insensible losses. This leads to a positive fluid balance which can not be readily explained. Method: We have used venous congestion plethysmography (VCP) a non-invasive method for measurement of microvascular parameters in limbs to investigate the changes in microvascular permeability (FFK) and the balance of Starling forces of patients undergoing surgery for unilateral femoral artery reconstruction (FEM) under epidural anaesthesia or abdominal aortic aneurysm repair (AAA) under general anaesthesia. The control group consisted of patients scheduled for inguinal hernia repair or hand surgery under general anaesthesia. All patients were measured 24 hours pre-operatively, immediately after the induction of anaesthesia or completion of epidural anaesthesia and on the 1^st. 5^th and 10^th postoperative day. The perioperative patient management followed a standard protocol and all patients with vascular disease were invasively monitored using indwelling arterial lines and central venous catheters. Continuous infusion of Ringers lactate and 6% Dextran 60 was sustained during the induction period. Each patient gave informed consent. Results: Preoperatively we found no significant difference in the mean FFK- values of controls (4.1±0.4, ml. min^?1 100?ml tissue^?1 mmHg^?1×10^?3=FFKU), the AAA (3.6±0.3?FFKU) and FEM (4.2±0.3?FFKU). After induction of anaesthesia the mean FFK value in the controls fell to 3.5±0.5?FFKU (p=0.07), whereas in the AAA patients we observed a significant increase to 4.7±0.2?FFKU (p< 0.005) and after epidural anaesthesia in FEM to 5.5±0.4?FFKU (p<0.001) respectively. Those post anaesthetic FFK values where significantly higher in FEM and AAA than in the controls (p<0.02). In AAA we found a significant positive correlation between the increase in FFK and the intraoperative fluid balance (r²=0.69, p<0.01). No such correlation was found in controls and FEM. The postoperative values of FFK where unchanged in the control group, whereas a further increase was seen in both patient groups with vascular disease, with a maximum in AAA on the 1^st postoperative day (to 5.4±0.4?FFKU mean both legs) and the 5^th postoperative day in FEM (to 7.3±1.7 non-ischemic leg, 7.1±1.2 ischemic leg FFKU). In both groups normal FFK values where found on the 10^th day after the operation. Conclusion: The data presented suggests an increase in extravascular fluid loss in patients undergoing vascular surgery, which becomes evident after the induction of general anaesthesia or completion of epidural anaesthesia. The positive correlation with the intraoperative fluid requirements may partially explain the often reported large intraoperative fluid requirements of patients undergoing AAA repair. The fact that the maximum change in fluid filtration capacity is found postoperatively may be explained by the additional effect of an ischemia/reperfusion injury in response to both the clamping an declamping of the artery and the increase in arterial blood flow to the limb due to the successful reconstruction of the blood vessel.     

Milzexstirpation bei myeloischer Leukämie

Zusammenfassung Wir sind natürlich weit davon entfernt, wie schon aus dem Wesen der ganzen Krankheit hervorgeht, von einer dauernden Besserung im Sinne einer Heilung zu sprechen; wir k?nnen aber wohl mit Recht behaupten, da? es uns in diesem Fall einermyeloischen Leuk?mie durch die in Acht und Bann getaneneSplenektomie gelungen ist, eineRemission von einer ganzen Reihe von Monatenzu erzielen und die Kranke, die bei der Aufnahme hoffnungslos dem nahen Tode verfallen schien, wieder arbeits und lebensfreudig gemacht zu haben — und sei es auch nur für eine Spanne Zeit, wobei noch bemerkenswert ist, da? diealeuk?mische Myelose nach der Operation in dieleuk?mische Formüberging. Auszugsweise vorgetragen auf der 43. Tagung nordwestdeutscher Chirurgen in Hamburg, Krankenhaus St. Georg, am 11. XII. 31.     

Mesenterialischämie bei selektiver Hirnperfusion

Background

Although perfusion of the mesenteric artery is compromised during complex aortic arch interventions with hypothermic circulatory arrest (HCA) and selective cerebral perfusion (SCP), deep hypothermia offers sufficient protection from ischemia. According to the trend in recent years, interventions on the thoracic aorta are, however, being carried out increasingly more under moderate (25-29°C) or mild hypothermia ((≥?30?°C). Under these conditions mesenteric damage cannot be avoided.

Aim

The aim of the experimental study using a large animal model was an evaluation of lower body perfusion (LBP) carried out in addition to SCP and the influence on visceral blood flow, oxidative damage and unspecific inflammatory response in the jejunum and colon during prolonged cardiac arrest.

Material and methods

After connection to an extracorporeal circulation (ECC) 14 female pigs (35-45 kg body weight BW) were cooled to 28°C and exposed to a 10 min HCA. The animals were then reperfused randomly in 2 groups: SCP group (n=7) with SCP flow at 10 ml/kg BW and a second group (n=7) with ischemia of the lower body (combined selective cerebral and lower body perfusion CLBP group) with SCP flow at 10 ml/kg BW and LBP flow 20 ml/kg BW per minute. After termination of the SCP all animals were systemically warmed, the ECC was disconnected after reaching a normal body temperature and the animals were hemodynamically monitored for a further 60 min. Perfusion of the mesenteric artery was measured by injection of fluorescent microspheres and the inflammation markers interleukin (IL) 6, tumor necrosis factor (TNF) alpha and p38 were measured in mesenteric tissue by immunological investigations and real-time PCR (RT-PCR). In addition oxidative DNA damage was determined perioperatively at six time points by flow cytometry in portal vein blood using fluorescence activated cell sorting (FACS): at baseline before connecting to ECC, after 5 min and 60 min of SCP and 5 min 30 min and 60 min after weaning from ECC.

Results

The isolated SCP resulted in a mesenteric artery residual flow of only 3 % of the physiological blood flow rate of 76?±?40 ml/min/100 g (colon) and 53?±?29 ml/min/100 g (jejunum), followed by reactive mesenteric hyperperfusion of up to 200 % in the reperfusion phase. In contrast CLBP led to a mesenteric residual flow of 50 % with relatively normal mesenteric perfusion after weaning from ECC. Furthermore, it could be shown that for moderate hypothermia combined perfusion is accompanied by a significantly lower development of lactate concentration (11 mmol/l compared to 15 mmol/l). The FACS analysis confirmed that the 70 min of reduced visceral perfusion leads to an increase in oxidative damage of DNA in the circulating visceral blood, independent of this is with or without perfusion of the lower body. The damage under SCP alone was higher. The semiquantitative immunohistological analysis of mesenteric tissue and the quantitative RT-PCR showed a significantly higher immunological activation in SCP alone compared to CLBP.

Conclusion

A combined CLBP with different low flow blood flow rates can be carried out practically. The additional perfusion of the lower body at 28°C leads to a clear improvement in perfusion of the mesenteric artery, lower development of lactate concentration and to lower immunological activation in mesenteric tissue.     

Über das Wesen der Hämorrhoiden

Ohne Zusammenfassung (Mit 5 Abbildungen.)