Blood taken immediately after fatal resuscitation attempts yields higher quality DNA for genetic studies as compared to autopsy samples

BACKGROUND

The out-of-hospital cardiac arrest (OHCA) in the young may be associated with a genetic predisposition which is relevant even for genetic counseling of relatives. The identification of genetic variants depends on the availability of intact genomic DNA. DNA from autopsy may be not available due to low autopsy frequencies or not suitable for high-throughput DNA sequencing (NGS). The emergency medical service (EMS) plays an important role to save biomaterial for subsequent molecular autopsy. It is not known whether the DNA integrity of samples collected by the EMS is better suited for NGS than autopsy specimens.

MATERIAL AND METHODS

DNA integrity was analyzed by standardized protocols. Fourteen blood samples collected by the EMS and biomaterials from autopsy were compared. We collected 172 autopsy samples from different tissues and blood with postmortem intervals of 14-168 h. For comparison, DNA integrity derived from blood stored under experimental conditions was checked against autopsy blood after different time intervals.

RESULTS

DNA integrity and extraction yield were higher in EMS blood compared to any autopsy tissue. DNA stability in autopsy specimens was highly variable and had unpredictable quality. In contrast, collecting blood samples by the EMS is feasible and delivered comparably the highest DNA integrity.

CONCLUSIONS

Isolation yield and DNA integrity from blood samples collected by the EMS is superior in comparison to autopsy specimens. DNA from blood samples collected by the EMS on scene is stable at room temperature or even for days at 4 °C. We conclude that the EMS personnel should always save a blood sample of young fatal OHCA cases died on scene to enable subsequent genetic analysis.

The emergency medical service has a crucial role to unravel the genetics of sudden cardiac arrest in young, out of hospital resuscitated patients: Interim data from the MAP-IT study

BACKGROUND

Genetics of sudden cardiac deaths (SCD) remains frequently undetected. Genetic analysis is recommended in undefined selected cases in the 2021 ERC-guideline. The emergency medical service and physicians (EMS) may play a pivotal role for unraveling SCD by saving biomaterial for later molecular autopsy. Since for high-throughput DNA-sequencing (NGS) high quality genomic DNA is needed. We investigated in a prospective proof-of-concept study the role of the EMS for the identification of genetic forms of SCDs in the young.

METHODS

We included patients aged 1-50 years with need for cardiopulmonary resuscitation attempts (CPR). Cases with non-natural deaths were excluded. In two German counties with 562,904 residents 39,506 services were analysed. Paired end panel-sequencing was performed, and variants were classified according to guidelines of the American College of Medical Genetics (ACMG).

RESULTS

769 CPR-attempts were recorded (1.95% of all EMS-services; CPR-incidence 68/100,000). In 103 cases CPR were performed in patients < 50y. 58% died on scene, 26% were discharged from hospital. 24 subjects were included for genotyping. Of these 33% died on scene, 37.5% were discharged from hospital. 25% of the genotyped patients were carriers of (likely) pathogenic (ACMG-4/-5) variants. 67% carried variants with unknown significance (ACMG-3). 2 of them had familial history for arrhythmogenic cardiomyopathy or had to be re-classified as ACMG-4 carriers due to whole exome sequencing.

CONCLUSION

The EMS contributes especially in fatal OHCA-cases to increase the yield of identified genetic conditions by collecting a blood sample on scene. Thus, the EMS can contribute significantly to primary and secondary prophylaxis in affected families.

Molecular autopsy and family screening in a young case of sudden cardiac death reveals an unusually severe case of FHL1 related hypertrophic cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy with a prevalence of about 1:200. It is characterized by left ventricular hypertrophy, diastolic dysfunction and interstitial fibrosis; HCM might lead to sudden cardiac death (SCD) especially in the young. Due to low autopsy frequencies of sudden unexplained deaths (SUD) the true prevalence of SCD and especially of HCM among SUD remains unclear. Even in cases of proven SCD genetic testing is not a routine procedure precluding appropriate risk stratification and counseling of relatives.

METHODS

Here we report a case of SCD in a 19-year-old investigated by combined forensic and molecular autopsy.

RESULTS

During autopsy of the index-patient HCM was detected. As no other possible cause of death could be uncovered by forensic autopsy the event was classified as SCD. Molecular autopsy identified two (probably) pathogenic genetic variants in FHL1 and MYBPC3. The MYBPC3 variant had an incomplete penetrance. The FHL1 variant was a de novo mutation. We detected reduced FHL1 mRNA levels and no FHL1 protein in muscle samples suggesting nonsense-mediated mRNA decay and/or degradation of the truncated protein in the SCD victim revealing a plausible disease mechanism.

CONCLUSION

The identification of the genetic cause of the SCD contributed to the rational counseling of the relatives and risk assessment within the family. Furthermore our study revealed evidences for the pathomechanism of FHL1 mutations.

Preventing pain during injection of propofol: effects of a new emulsion with lidocaine addition

BACKGROUND AND OBJECTIVE

Previous studies found that lidocaine addition to propofol long-chain triglyceride was associated with a lower incidence of injection pain than medium-chain triglyceride/long-chain triglyceride formulation, but the incidence was still high (31-40%). Our study investigated whether the incidence of injection pain could be further reduced by the addition of lidocaine (10 mg, 20:1) to propofol medium-chain triglyceride/long-chain triglyceride.

METHODS

In a randomized double-blind controlled trial 464 patients scheduled to undergo regional anaesthesia were assigned to receive one of the following four options: propofol medium-chain triglyceride/long-chain triglyceride + lidocaine, propofol long-chain triglyceride + lidocaine, propofol medium-chain triglyceride/long-chain triglyceride or propofol long-chain triglyceride. Propofol was injected to reach grade 3 of the Observer's Assessment of Alertness/Sedation scale.

RESULTS

Incidence of injection pain was 18% in the propofol medium-chain triglyceride/long-chain triglyceride + lidocaine group, 31% in the propofol long-chain triglyceride + lidocaine group, 47% in the propofol medium-chain triglyceride/long-chain triglyceride group and 60% in the long-chain triglyceride group. Propofol medium-chain triglyceride/long-chain triglyceride + lidocaine was associated with a statistically significant reduced incidence of injection pain compared with propofol long-chain triglyceride +lidocaine (P =0.0249, number needed to treat =7.7).

CONCLUSIONS

Premixing propofol medium-chain triglyceride/long-chain triglyceride with lidocaine is one of the most effective measures currently available to reduce the incidence of injection pain in sedated patients during regional anaesthesia.

Efficacy of sufentanil addition to ropivacaine epidural anaesthesia for Caesarean section

BACKGROUND

This prospective double-blind trial evaluated the effect of sufentanil addition to epidural ropivacaine for elective Caesarean section.

METHODS

Sixty healthy parturients were randomly assigned to receive an initial dose of 90 mg of plain ropivacaine, or 90 mg of ropivacaine plus 10 or 20 microg of sufentanil (n = 20 each). Before surgery, if necessary, additional epidural ropivacaine was injected. Primary outcome parameter was time to achieve sensory block at T4.

RESULTS

Time to reach the sensory block was remarkably reduced (P < 0.001 each) by addition of 10 or 20 microg of sufentanil (21 +/- 8 min, 15 +/- 5 min, 11 +/- 4 min in the plain ropivacaine, the 10- and 20-microg sufentanil groups, respectively) whereas the visual analogue scale (VAS) scores at delivery were significantly reduced (P = 0.028) only by 20 microg of sufentanil (32 +/- 35 mm in the plain ropivacaine vs. 9 +/- 19 mm in the 20-microg sufentanil groups). The total dose of ropivacaine was significantly lower (P = 0.005) in patients receiving 20 microg of sufentanil (100.5 +/- 15.0 mg) compared with those treated with plain ropivacaine (118.5 +/- 17.3 mg). The incidence of maternal side-effects (hypotension, bradycardia, nausea, vomiting, shivering, pruritus) and neonatal outcome [APGAR score, neurologic and adaptive capacity (NAC) score, umbilical cord blood-gas values] did not differ between the groups.

CONCLUSION

Our results suggest that addition of 20 microg of sufentanil improved the epidural anaesthesia with ropivacaine 0.75% for Caesarean section.

Epidural ropivacaine 1% with and without sufentanil addition for Caesarean section

BACKGROUND

So far only ropivacaine concentrations of 0.5 and 0.75% have been used for Caesarean section. This prospective double-blind trial evaluated the anaesthetic quality of ropivacaine 1% with and without sufentanil addition.

METHODS

Three groups of patients (n=20 each) scheduled for an elective Caesarean section were studied. The patients received initially 120 mg ropivacaine, or 120 mg ropivacaine plus 10 microg or 20 microg sufentanil. Additional epidural ropivacaine was injected if necessary. Primary outcome parameter was time to achieve sensory block at T4. Moreover, pain intensity at delivery (visual analogue scale, VAS), incidence of maternal side-effects (hypotension, bradycardia, nausea, vomiting, shivering, pruritus), and neonatal outcome (Apgar score, neurologic and adaptive capacity score, umbilical cord blood-gas values) were recorded.

RESULTS

The onset time for the sensory block was not significantly different among the groups. Also, VAS scores at delivery did not differ significantly between the plain ropivacaine 1% group (18 +/- 29 mm), the 10-microg sufentanil group (1 +/- 5 mm), and the 20-microg sufentanil group (6 +/- 18 mm). The total dose of ropivacaine was significantly higher in the plain ropivacaine 1% group (145 +/- 19 mg) compared to the patients receiving additional 10 microg sufentanil (130 +/- 15 mg, P = 0.02) or 20 microg sufentanil (129 +/- 16 mg, P = 0.01). The incidence of maternal side-effects and neonatal outcome were similar in all groups.

CONCLUSION

Ropivacaine 1% alone provided sufficient analgesia. Sufentanil addition did not significantly improve the quality of epidural anaesthesia with ropivacaine 1.0% for Caesarean section.

[Spontaneous intracranial hypotension. A rare syndrome with good treatment options]

The spontaneous intracranial hypotension syndrome is a rare event but with increasing tendency. The clinical characteristics are comparable to those occurring after dural puncture and the most important clinical finding is the postural headache. The syndrome results from cerebrospinal fluid leakage but its etiology is still nearly unknown. The leaks are mainly located cervically or at the cervicothoracic junction. The syndrome may be associated with cranial subdural fluid build-up. Magnetic resonance imaging of the brain typically reveals diffuse pachymeningeal enhancement, frequently in association with displacement of the brain. Knowledge of this can be helpful to facilitate the diagnosis. Although conservative measures are often initially undertaken, placement of an epidural blood patch is the treatment of choice. Because of its similarity to postdural puncture headache, anaesthesiologists and pain therapists are increasingly involved in diagnosis and therapy. We report 2 patients with spontaneous intracranial hypotension. In addition to the cardinal feature of a postural headache, the patients suffered from subdural fluid build-up demonstrated by cranial magnetic resonance imaging.

Incidence of pain after intravenous injection of a medium-/long-chain triglyceride emulsion of propofol. An observational study in 1375 patients

BACKGROUND AND OBJECTIVE

To assess incidence and intensity of pain on intravenous injection of propofol (CAS 2078-548) in an emulsion of medium-chain/long-chain triglycerides (MCT/LCT, 50:50) in patients undergoing different elective surgical interventions.

METHODS

The new solvent was used for induction of general anesthesia. Spontaneous pain reactions and pain elicited upon questioning were assessed. Patients were asked to grade the pain as mild, moderate or severe. Co-medication with sedative or analgesic drugs, size of the intravenous cannulae, site of injection and administration as a single bolus or in divided doses were recorded.

RESULTS

Overall incidence of pain was 28.4% (390 out of 1375 patients). Twelve percent of the patients complained spontaneously and 16.4% reported pain after questioning. Pain intensity was graded as mild by 16.7% of the patients. The incidence of pain was significantly less when using an antecubital vein compared with a forearm or dorsal hand vein (p = 0.017 spontaneously reported pain, p = 0.001 pain elicited upon questioning). The number of patients complaining spontaneously of pain was significantly lower (p = 0.006) for large size than for small and medium size cannulae.

CONCLUSIONS

The incidence of pain on injection of a medium-/long-chain triglyceride propofol formulation was 28.4% with 16.7% of the patients reporting mild pain. The use of an antecubital vein or a large size venous cannula appears to reduce the injection pain.

Linkage disequilibrium between tumor necrosis factor (TNF)-alpha-308 G/A promoter and TNF-beta NcoI polymorphisms: Association with TNF-alpha response of granulocytes to endotoxin stimulation

OBJECTIVE

Controversial data have been reported on the association between the tumor necrosis factor (TNF)-alpha-308 G[U279C]A promoter polymorphism or the TNF-alpha I polymorphism with TNF-alpha plasma concentrations. The purpose of this study was to evaluate whether there is a linkage disequilibrium between the two polymorphisms. Moreover, the influence of these polymorphisms on the TNF-alpha synthesis of activated granulocytes was studied.

DESIGN

Analysis of TNF-alpha concentrations of human whole blood after endotoxin stimulation.

SETTING

Medical research laboratory.

PATIENTS

Healthy human volunteers.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Healthy human volunteers were genotyped for both TNF polymorphisms by means of polymerase chain reaction. TNF-alpha plasma concentrations were determined with chemiluminescence after incubation of whole blood with endotoxin. A strong (p <.0001) linkage disequilibrium was found for the TNF-beta I and the TNF-alpha-308 genetic polymorphisms. Almost all individuals homozygous for the TNF-B2 allele of the TNF-beta I polymorphism were also TNF-alpha-308 G homozygotes. Carriers of the TNF-alpha-308 genotype AG had a significantly higher TNF-alpha production capacity than G homozygotes. The TNF-beta I genotype TNF-B1/TNF-B2 was associated with significantly higher TNF-alpha concentrations than the genotype TNF-B2/TNF-B2. Individuals homozygous for the TNF-B2 and the TNF-alpha-308 G alleles had a significantly reduced TNF-alpha response compared with individuals heterozygous for both TNF polymorphisms.

CONCLUSIONS

A linkage disequilibrium between the two TNF polymorphisms was found. This study revealed a significant association between genotype and phenotype for both TNF polymorphisms. Heterozygosity for both TNF polymorphisms is associated with an increased TNF-alpha response.

The CD14-260 C --> T promoter polymorphism co-segregates with the tumor necrosis factor-alpha (TNF-alpha)-308 G --> A polymorphism and is associated with the interleukin-1 beta (IL-1 beta) synthesis capacity of human leukocytes

Genetic variations contribute to the interindividual variance in the cytokine response to endotoxin. The gene of tumor necrosis factor-alpha (TNF-alpha) carries a polymorphism at position -308 of the promoter, consisting of a G/A exchange. To further elucidate the inherited mechanisms influencing cytokine levels, healthy human blood donors were studied. Genotyping for the TNF-alpha -308 and the CD14 -260 C/T promoter polymorphisms was carried out by real-time polymerase chain reaction assay using specific fluorescence-labelled hybridisation probes. A human whole blood assay was used to study the leukocyte TNF-alpha and IL-1 beta synthesis capacity upon endotoxin stimulation. We found a linkage disequilibrium between the TNF-alpha -308 G/A and the CD14 -260 C/T polymorphisms (p = 0.043). The CD14 -260 polymorphism was associated with IL-1 beta levels (p = 0.033) and higher values were found in C homozygotes. No association was found between the CD14 -260 genotypes or the TNF-alpha -308 - CD14 -260 genotypes and the TNF-alpha response.

Ropivacaine epidural anesthesia and analgesia versus general anesthesia and intravenous patient-controlled analgesia with morphine in the perioperative management of hip replacement. Ropivacaine Hip Replacement Multicenter Study Group

The aim of our study was to compare epidural anesthesia and analgesia (EDA) with ropivacaine versus general anesthesia followed by IV patient-controlled analgesia with morphine (GA/PCA) after hip replacement regarding pain, side effects, and discharge from the postanesthesia care unit. After ethics committee approval, randomization, and informed consent, 90 patients were enrolled. In Group EDA, epidural anesthesia (ropivacaine 10 mg/mL, 15-25 mL) was followed by an epidural infusion (2 mg/mL, 4-6 mL/h for 24 h, plus top-up doses of 6-10 mL for 48 h). GA/PCA patients received general anesthesia (isoflurane/N2O/fentanyl) followed by IV patient-controlled analgesia with morphine postoperatively. Pain was assessed by using visual analog scales (0-100 mm) at rest and during physiotherapy. Pain at rest was less in the EDA (n = 43) group than in the GA/PCA (n = 45) group (at 10 h: 11.8+/-12.9 vs. 28.4+/-17.1 [P< 0.001]; at 24 h: 14.3+/-11.7 vs. 24.0+/-17 [P<0.01]; in 48 h: 14.3+/-9.3 vs. 21.1+/-17.4 [P = 0.1]). Whereas EDA patients were deemed ready for discharge from the postanesthesia care unit earlier than GA/PCA patients (5.6+/-8.9 vs. 39.7+/-41.5 min), the actual discharge time was comparable. The median time for first passage of flatus was shorter in the EDA group than in the GA/PCA group (26 vs. 47 h). Nausea and vomiting were more common in the GA/PCA group than in the EDA group (16% vs. 28% and 11% vs. 22%, respectively), whereas hypotension (11% vs. 4%) and bradycardia (14% vs. 2%) were less frequent. Under the conditions of the present study, EDA with ropivacaine provided pain control after hip replacement superior to that provided by IV patient-controlled analgesia with morphine, particularly during the first 24 h. Both approaches to pain management were equally safe.

IMPLICATIONS

Compared with general anesthesia and postoperative IV patient-controlled analgesia with morphine, epidural anesthesia and analgesia with the new local anesthetic ropivacaine enables patients to be discharged sooner from a postanesthesia care unit and provides superior pain relief during the first 24 h after hip replacement.

Volume replacement with gelatin or hydroxyethylstarch solutions does not impair somatosensory evoked potential monitoring: a haemodilution study in conscious volunteers

The influence of haemodilution with colloids on somatosensory evoked potentials in non-premedicated volunteers is reported. In seven volunteers (randomized crossover design), blood (20 mL kg-1 within 30 min) was removed and simultaneously replaced by gelatin 3% or hydroxyethylstarch 6%. After 30 min, blood was retransfused within 30 min. Median and posterior tibial nerve somatosensory evoked potentials were recorded from the cortex, second cervical vertebra, Erb's point and 1st lumbar vertebra, respectively. One volunteer experienced a severe allergic reaction to gelatin, therefore only six gelatin trials were evaluated. Haemodilution decreased the haematocrit from 39.8 +/- 1.6% (mean +/- SD) to 31.1 +/- 2.0% (gelatin) and from 40.7 +/- 1.7% to 29.8 +/- 1.5 % (hydroxyethylstarch), respectively. Retransfusion increased haematocrit to 34.4 +/- 0.9% (gelatin) and to 34.2 +/- 1.3% (hydroxyethylstarch). Neither haemodilution with gelatin nor haemodilution with hydroxyethylstarch or retransfusion influenced evoked potentials. In conclusion, the treatment of blood loss up to 30% of estimated blood volume with gelatin or hydroxyethylstarch will not affect somatosensory evoked potential monitoring provided normovolaemic conditions are maintained.

Isovolaemic haemodilution with hydroxyethylstarch has no effect on somatosensory evoked potentials in healthy volunteers

BACKGROUND

An animal study in anaesthetized baboons demonstrated that somatosensory evoked potentials (SSEP) can be affected by extreme haemodilution. This might lead to misinterpretation and reduce the value of intraoperative SSEP monitoring when colloids are administered. In the present study, the effect of haemodilution (HD) and subsequent retransfusion of autologous blood on SSEP was determined in healthy non-premedicated volunteers.

METHOD

Acute isovolaemic HD served as a model for blood loss immediately replaced with colloids. In 12 volunteers, 20 ml/kg.bw blood was withdrawn within 30 minutes and simultaneously multaneously replaced with 6% hydroxyethylstarch (HES). 30 minutes later, the autologous blood was retransfused within 30 minutes. Recording sites and parameters were: 1. Median nerve SSEP: cortical, cervical (C2), Erb's point; 2. Posterior tibial nerve SSEP: cortical, cervical (C2), lumbar (L1). In addition to SSEP latency and amplitude, median and tibial nerve central conduction times, spinal conduction time and nerve conduction velocity were determined. Serial SSEP measurements were made before, during and after HD and retransfusion every 15 minutes.

RESULTS

HD consisting of a withdrawal volume of 1550 +/- 155 ml (mean +/- SD) induced a decrease in haematocrit from 42.0 +/- 3.1% to 29.6 +/- 1.6% (P < 0.001). Following retransfusion, haematocrit increased to 35.0 +/- 2.1% (P < 0.001). Neither HD nor retransfusion influenced SSEP parameters.

CONCLUSION

We conclude from our data that the therapy of blood loss up to 30% of estimated blood volume with HES does not affect SSEP monitoring as long as normovolaemia is maintained.

[Does controlled hypotension with nitroprusside affect platelet function?]

Induced hypotension is an accepted technique to reduce intraoperative blood loss and thereby ensures satisfactory operating conditions, especially in microscopic interventions. Sodium nitroprusside (NP), which is often used for induced hypotension, was reported to inhibit platelet aggregation in vitro. Impairment of platelet function implies a higher bleeding risk, which would make the use of NP for induced hypotension questionable. METHODS. With the approval of the local ethics committee, 30 patients scheduled for nasal septum operations were included in this randomised study. For induction of anaesthesia 2 mg vecuronium, 0.1 mg fentanyl, 0.2 mg/kg etomidate, and 1 mg/kg succinylcholine were used. After tracheal intubation the patients inhaled 1.0-1.5 vol.% isoflurane in a gas mixture containing 66% nitrous oxide in oxygen. Fifteen patients received an i.v. infusion of NP for 60 min. The concentrations chosen produced a decrease of mean arterial blood pressure to 50 mm Hg. Blood samples were taken before induction of anaesthesia; after induction of anaesthesia but before beginning of the operation; and 60 min after the beginning of the operation. This time-point coincided with the end of NP administration in the study group. The last blood sample was drawn the morning after the operation. Platelet function was determined in platelet-rich plasma by a turbidometric method after adding 22 mumol/l epinephrine to induce aggregation. The spontaneous aggregation was measured in whole blood using impedance aggregometry. Data within one group were analysed using analysis of variance. Student's t-test for unpaired values served to compare data between the two groups. RESULTS. Biometric data in the two groups were comparable. The blood loss in the control group [265 (190-410) ml] significantly exceeded (P < 0.05) that in the hypotensive group [125 (75-210) ml]. No significant changes in platelet function were found throughout the study period in the patients treated with NP. In the control patients the epinephrine-induced aggregation increased significantly from 53.1 +/- 5.3% before anaesthesia to 72.1 +/- 3.3% the morning after the intervention. The spontaneous aggregation showed a significant increase from 0.718 +/- 0.338 Ohm/h before anaesthesia to 2.164 +/- 0.442 Ohm/h 60 min after the beginning of the operation. The value on the 1st postoperative day (2.266 +/- 0.448 Ohm/h) was also significantly higher than the basal value. CONCLUSIONS. In contradiction to in vitro studies using high concentrations of NP, we could not find a decrease in platelet aggregation due to hypotensive anaesthesia with this drug in vivo. In the control group a significant increase in platelet aggregation was observed, which was probably counteracted in the hypotensive patients by the interaction of NP with cyclic guanosine monophosphate (c-GMP). NP augments the intracellular concentration of c-GMP, which is known to decrease platelet aggregation.

Increase of interleukin-6 plasma concentrations and HLA-DR positive T-lymphocytes after hypotensive anaesthesia with sodium nitroprusside

Interleukin-6 (IL-6), a cytokine involved in the pathogenesis of sepsis and septic shock, and lymphocyte subpopulations were measured in blood circulation of patients receiving sodium nitroprusside (SNP) for induction of hypotension. The aim of this study was to evaluate whether this procedure influences distribution of lymphocyte subsets and IL-6 response. 30 patients of ASA physical status I and II scheduled for nose-septum correction were randomly assigned to the SNP- or control group (without SNP). Patients were anaesthetized with fentanyl, etomidate and isoflurane in 66% nitrous oxide. SNP was administered continuously during 60 min and mean arterial blood pressure was reduced to 50 mmHg. Before and after induction of anaesthesia, 60 min after the beginning of the operation (end of SNP-infusion) and on the first postoperative day, IL-6 plasma concentrations were determined by ELISA. The percentages of B-, T-lymphocytes, T-helper, T-suppressor cells and HLA-DR positive (activated) T-lymphocytes were examined by direct immunofluorescence using monoclonal antibodies. On the first day after surgery IL-6 plasma concentrations were significantly elevated in the SNP-group compared to preoperative values. In this group the values were higher than in control patients [30.5 (10.9-47.5) pg/ml vs. 17.4 (8.5-21.5) pg/ml]. The percentage of HLA-DR positive T-cells was 25.8 +/- 4.9% in the patients with SNP on the first postoperative day; it was significantly higher than in control patients [16.5 +/- 3.7%]. We conclude that SNP-administration increases percentage of activated T-cells and IL-6 secretion.

Intercostal nerve block, interpleural analgesia, thoracic epidural block or systemic opioid application for pain relief after thoracotomy?

The purpose of this study was to investigate the effect of different pain-relief methods (regional and systemic) following thoracotomies on the cardiovascular system, pulmonary gas exchange, various endocrine parameters and subjective perception. A further aspect was to evaluate the benefits of interpleural analgesia as a new regional technique against already established regional techniques, such as intercostal nerve block and thoracic epidural block. All postoperative pain methods led to a significant time-dependent reduction of the adrenaline concentrations in plasma while the noradrenaline concentrations did not change significantly. There were no statistical differences in catecholamine concentrations among the different study groups, although the mean concentrations of adrenaline in patients having a thoracic epidural block for pain relief were lower in comparison to the findings in other groups. The plasma concentrations of the "stress metabolites", such as glucose, free fatty acids and lactate, as well as the haemodynamic (mean arterial pressure, heart rate) and pulmonary parameters (blood gas analyses), showed no significant differences among groups. In contrast to the other pain-relieving methods, interpleural analgesia did not lead to sufficient pain relief in that 7 out of 10 patients needed supplementary systemic opioid therapy. Therefore, interpleural analgesia for pain relief following thoracotomies cannot be recommended.

[Ultrafiltration as a fast and simple method for determination of free and protein bound prilocaine concentration. Clinical study following high-dose plexus anesthesia]

Ultrafiltration as a Fast and Simple Method to Separate Free and Protein Bound Concentrations of Local Anesthetics/Pharmacokinetic studies following high-dose anesthesia of the axillary plexus. As many other drugs amide-type local anesthetics are protein bound in plasma. The extent of binding varies between local anesthetics. The free, non protein-bound fraction of these drugs is mainly responsible for cardiovascular and central-nervous side effects. If high doses are necessary for regional anesthetic procedures it seems reasonable to determine the pharmacological active, non protein-bound fraction in addition to the total concentration of the local anesthetic drug. Analyses of protein binding was performed using an ultrafiltration method which is discussed in this paper. Total (HPLC) and unbound plasma levels (combination of ultrafiltration and HPLC) of the local anesthetic drug in central venous blood were studied in 20 healthy orthopedic patients, undergoing plastic surgery of the upper limb (elbow, forearm, hand), over a time period of 90 min, when performing axillary plexus block with 30 ml prilocaine (CAS 721-50-6) 2% (= 600 mg). Separation of the local anesthetic fractions was achieved using the ultrafiltration system MPS-1, equipped with a YMT-membrane. These membranes have a narrow pore size retaining molecules larger than 30000 Dalton. Ultrafiltration was accomplished by subjecting 1.2 ml of plasma to centrifugation at 2000 x g for 60 min at 30 degrees C using a clinical centrifuge equipped with a 35 degree angle head rotor. The plasma samples were adjusted to physiological pH (7.40) with a sodium-potassium-phosphate buffer. The tightness of the used membrane was controlled by a micromethod for protein estimation (sensitivity 10 micrograms/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

[Hyperthermic reaction in the perioperative phase in 2 children with acute lymphoblastic leukemia of B-cell type]

Acute lymphatic leukemia (ALL) represents one of the most frequent malignancies in childhood. Central venous access ports or partly implanted silicone catheters are usually placed for high-dose chemotherapy in these children. We report two patients aged 7 and 3 years with acute lymphoblastic beta-cell leukemia (B-ALL), a less common subtype of ALL, which presented with hyperthermia (38.4 degrees C and 39 degrees C) during anesthesia with isoflurane for implantation of a central venous catheter. The hyperthermic reactions were accompanied by an increase in expired CO2 and acidosis as well as moderate elevation of heart rate and blood pressure. As in both patients the history and preoperative findings did not reveal signs of infection or other causes of fever, the observed alterations were interpreted as symptoms of malignant hyperthermia triggered either by succinylcholine or isoflurane, which were used in both children. In addition, the hyperthermia responded to administration of dantrolene sodium according to dose recommendations for treatment of malignant hyperthermia. In one of the patients, withdrawal of dantrolene during the initial postoperative hours was followed by a recurrent increase in body temperature, which once again could be suppressed by additional dantrolene infusion. According to the literature, malignant hyperthermia has occasionally been described in children with malignancies such as leukemia or Burkitt's lymphoma. Our observations indicate that children with B-ALL may be especially susceptible to malignant hyperthermia. Close monitoring of body temperature and expiratory CO2 are therefore indicated in these children, and dantrolene therapy should be started immediately in case of increased temperature during anesthesia.