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Intravenous fentanyl (10 mcg/kg) or saline (control) was randomly administered to 10 healthy sevoflurane-mono-anaesthetized piglets. Trembling was assessed by two blinded observers using a visual analogue scale (VAS) and a simple ordinal scale at baseline and 5 min (T5) after drug administration. If no trembling was observed at that time point, the opposite treatment was administered and piglets were re-evaluated after another 5 min (T10). Four out of five piglets showed trembling after fentanyl (T5), while none given saline showed any trembling. With fentanyl the VAS scores were significantly higher at T5 compared either with baseline or with the control treatment. Control animals received fentanyl after the 5 min evaluation and all piglets showed clear trembling afterwards. The median time after fentanyl administration until first muscle tremors was 51 (20-840) s. In summary, nine out of 10 sevoflurane-anaesthetized piglets showed muscle tremors after intravenous fentanyl. Tremors subsided over time and no specific treatment was necessary., (© The Author(s) 2015.)

Background: In critically ill patients with significant pulmonary hypertension (PH), close perioperative cardiovascular monitoring is mandatory, considering the increased morbidity and mortality in this patient group. Although the pulmonary artery catheter is still the standard for the diagnosis of PH, its use to monitor cardiac output (CO) in patients with PH is decreasing as a result of increased morbidity and possible influence of tricuspid regurgitation on the measurements. However, continuous CO measurement methods have never been evaluated under PH regarding their agreement and trending ability. In this study, we evaluated the influence of acute PH and different CO states on transpulmonary thermodilution (TPTD) and calibrated pulse contour analysis (PiCCO; both assessed with PiCCO plus™), intermittent pulmonary artery thermodilution (PATD), and continuous thermodilution (CCO) compared with a modified Fick method (FICK) in an animal model., Methods: Nine healthy pigs were studied under anesthesia. PH of 25 and 40 mm Hg (by administration of the thromboxane analog U46619), CO decreases, and CO increases were induced to test the different CO measurement techniques over a broad range of hemodynamic situations. Before each step, a new baseline data set was collected. CO values were compared using Bland-Altman analysis; trending abilities were assessed via concordance and polar plot analysis. The influence of pulmonary pressure on CO measurements was analyzed using linear mixed models., Results: A mean bias of -0.26 L/min with prediction intervals of -0.88 to 1.4 L/min was measured between TPTD and FICK. Their concordance rate was 100% (94%-100% confidence interval), and the mean polar angle -3° with radial limits of agreement of ±28° indicated good trending abilities. PATD compared with FICK also showed good trending ability. Comparisons of PiCCO and CCO versus FICK revealed low agreement and poor trending results with concordance rates of 84% (71%-93%) and 88% (74%-95%), mean polar angles from -17° and -19°, and radial limits of agreement of ±45° and 40°. Pulmonary pressures influenced only the difference between FICK and PiCCO, as assessed by linear mixed models., Conclusions: TPTD compared with FICK was able to track all changes induced during the study period, including those by PH. It yielded better agreement than PATD both compared with FICK. PiCCO and CCO were not mapping all changes correctly, and when used clinically in unstable patients, regular controls with intermittent techniques are required. Acute pharmacologically induced PH did influence the difference between FICK and PiCCO.

Background: Modern high volume-low pressure (HVLP) endotracheal tubes (ETT) cuffs can seal the trachea using baseline cuff pressures (CP) lower than peak inspiratory airway pressures (PIP). The aim of the study was to determine whether this technique reduces the damage to the tracheal mucosa compared to constant CP of 20 cmH(2)O., Methods: Eighteen piglets were intubated with an ID 4.0 mm HVLP cuffed ETT (Microcuff PET) and artificially ventilated with 20 cmH(2)O PIP and 5 cmH(2)O PEEP. Animals were randomly allocated to two groups of CP: group A (just seal; n = 9) and group B (20 cmH(2)O; n = 9), controlled constantly with a manometer during the following 4-h study period under sevoflurane anesthesia. After euthanasia, cuff position was marked in situ. Damage in the cuff region was evaluated with scanning electron microscopy (SEM) examination by grading of mucosal damage and by estimating percentage of intact mucosal area both by a blinded observer., Results: Maximal CP to seal the trachea in group A ranged from 12 to 18 cmH(2)O (median: 14 cmH(2)O). Using a mixed effects model approach, the estimated mean effect of group B vs group A was an increase of 17.9% (SE 8.1%) higher proportion of pictures with an area of at least 5% intact mucosa (P = 0.042)., Conclusion: Minimal sealing pressures with cyclic pressure changes from CP did not result in decreased damage to the tracheal mucosa compared to constant CP of 20 cmH(2)O in this short-term animal trial., (© 2012 Blackwell Publishing Ltd.)

Objectives: Objective signs to detect inadvertent intravascular injection of local anesthetics are essential in the anesthetized pediatric patient. For early detection of intravenous bupivacaine administration, it was shown that an epinephrine containing test dose reliably provoked T-wave alterations, changes in heart rate (HR) and blood pressure, whereas intravenous injection of plain bupivacaine could not be detected until high doses were applied. This study investigates electrocardiographic and hemodynamic alterations caused by intravenous ropivacaine., Methods: Twenty-four piglets, anesthetized with sevoflurane, were randomized into two groups: Group R received as test dose plain ropivacaine 0.2% and group RE, ropivacaine 0.2% + epinephrine 5 μg·ml(-1) . Under stable conditions, 0.2 ml kg(-1) of the test solution was intravenously injected. Twenty minutes later, 0.4 ml kg(-1) was applied. A positive effect was defined as HR increase ≥ 10 bpm, increase in mean arterial pressure (MAP) ≥ 15 mmHg, T-wave increase ≥ 25% baseline. In another setting ropivacaine was intravenously infused until cardiac arrest., Results: After injection of 0.2 or 0.4 ml kg(-1) test solution, a positive increase in HR and MAP was found in 0% of group R and in 100% of group RE. An increase in T-wave ≥ 25% was found in 42% of group R and in 100% of group RE. During intoxication, T-elevation was seen in 83%., Conclusions: An epinephrine containing test dose ropivacaine reliably provoked T-wave elevations and increases in HR and MAP. A small dose plain ropivacaine caused T-elevations in a remarkable percentage, whereas higher, quite toxic doses provoked T-elevations in most of the pigs., (© 2012 Blackwell Publishing Ltd.)

Background: The aim of this study was to investigate ECG and haemodynamic alterations provoked by a test dose of bupivacaine, epinephrine, and their combination., Methods: Paediatric patients undergoing general anaesthesia were randomized into three groups. After anaesthesia induction and tracheal intubation, 0.2 ml kg(-1) (max. 3 ml) of the corresponding test solution was i.v. injected: bupivacaine 0.125% (Group B), bupivacaine 0.125% plus epinephrine 1:200 000 (Group BE), or epinephrine 1:200 000 (Group E). ECG was printed and analysed post hoc. Non-invasive arterial pressure (AP) was measured at 1 and 2 min after test dose injection. Increases in T-wave of ≥ 25%, in heart rate (HR) of ≥ 10 beats min(-1), and in systolic AP of ≥ 15 mm Hg above baseline value were considered a positive result., Results: A total of 105 children aged 0.2-16 (median 6.8) yr were enrolled. Test dose injection provoked T-wave elevation in 0%, 85%, and 89% of patients in Groups B, BE, and E, respectively. A positive increase in HR was found in 0%, 68%, and 76%. A positive increase in AP at 1 min was found in 0%, 88%, and 94% and at 2 min in 0%, 42%, and 59%. A decrease in HR of ≥ 10 beats min(-1) was observed in 6%, 76%, and 69%. Alterations in T-wave and HR were significantly influenced by age., Conclusions: ECG and haemodynamic alterations after i.v. injection of a local anaesthetic test dose were significantly influenced by epinephrine. T-wave elevation, increase in AP, and changes in HR are highly reliable variables, particularly when age is taken into account.

In veterinary medicine, point-of-care testing (POCT) techniques have become popular, since they provide immediate results and only small amounts of blood are needed. However, their accuracy is controversial. Pigs are often used for research purposes and accurate measurement of haemoglobin (Hb) is important during invasive procedures. The aim of this study was to evaluate two different Hb POCT devices in neonatal pigs. A prospective study with 57 pigs of 3-6 weeks of age, weighing 4.1-6.2 kg (median 5.1 kg) was performed. Fifty-seven blood samples were analysed for Hb using a conductivity-based and a photometrical POCT device and compared with a photometrical reference method. Statistical analysis was performed with Bland-Altman analysis, Spearman correlation and Passing-Bablok regression analysis. Hb values ranged from 32 to 108 g/L (median 80 g/L) using the reference method. The bias of the photometrical method (HemoCue(®)) to the reference method was -1 g/L, with limits of agreement (LOA) of -7 to 6 g/L. The conductivity-based method (i-STAT(®)) had a bias of -15 g/L with LOA from -24 to -6 g/L. There was a significant association between protein values and the bias of i-STAT versus CellDyn (r(2) = 0.27, P < 0.05) but not with the bias of HemoCue versus CellDyn (r(2) = 0.001, P = 0.79). The lower the protein values were, the lower the Hb values were measured by the i-STAT. The conductivity-based measurement of Hb constantly underestimated Hb values, whereas the photometrical method demonstrated a better accuracy and is therefore more reliable for on-site measurement of Hb in pigs.

Background: The aim of the study was to compare international normalized ratio (INR) results obtained by point-of-care testing (i-STAT® device) with the reference laboratory INR in children undergoing major surgery with expected significant blood loss., Methods:   Pediatric patients undergoing craniofacial, spine, hip, or cancer surgery were included. Blood samples for coagulation testing were tested at several intraoperative time points and generally withdrawn from the arterial catheter, if accessible. A volume of 1.4 ml citrated blood was used for the reference laboratory INR test, and 0.1 ml of blood was taken for the whole blood INR test using the i-STAT® device. Blood samples for both tests were withdrawn at the same time and immediately analyzed with both devices., Results: A total of 169 paired blood samples were taken intraoperatively from 44 pediatric patients [IQR 0.9-10.7 years (median 3.3)]. Reference laboratory INR ranged from 0.96 to 3.43 (mean 1.40; sd 0.32) and INR of i-STAT® from 0.95 to 2.29 (mean 1.26; sd 0.22). The correlation coefficient was 0.83 (P < 0.001), and the bias values were 0.12 and 0.55 at the medical decision level of ≤2.0 and >2.0, respectively., Conclusions: In the perioperative setting, point-of-care INR testing in children using the i-STAT® device is a reliable and easy-to-handle method for INR values ≤2.0, while INR values >2.0 might be underestimated., (© 2011 Blackwell Publishing Ltd.)

Background: Intravascular application of a small dose of local anesthetics (LA) with epinephrine as well as larger doses of LA under sevoflurane anesthesia results in increase in T-wave amplitude in the electrocardiogram (ECG). The aim of this study was to elucidate whether propofol anesthesia affects these ECG alterations or not., Methods: Thirty neonatal pigs were randomized into two groups. Group 1 was anesthetized with sevoflurane, group 2 with sevoflurane plus continuous propofol infusion (10 mg·kg(-1)·h(-1)). A test dose of 0.2 ml·kg(-1) bupivacaine 0.125% + epinephrine 1 : 200,000 was injected intravenously. Arterial pressure was monitored. ECG was analyzed for changes in T-wave amplitude (positive if ≥25% baseline) and heart rate. In another setting, bupivacaine 0.125% was intravenous infused at a rate of 4 mg·kg(-1)·min(-1). ECG was analyzed for alteration in T-wave amplitude and heart rate at 1.25, 2.5, and 5 mg·kg(-1) bupivacaine infused., Results: T-wave elevation after the administration of an epinephrine containing LA test dose was similar between the two groups. Increase in heart rate caused by the test dose were significantly higher in group 2 (P = 0.008). During continuous bupivacaine administration, T-wave elevation occurred in 40% and 71% (group 1 and 2) at 1.25 mg·kg(-1), in 80% and 100% at 2.5 mg·kg(-1), and in 93% and 86% at 5 mg·kg(-1) bupivacaine infused., Conclusion: Continuous propofol infusion does not suppress the ECG signs of a systemically administered epinephrine containing LA test dose nor does it suppress the ECG signs caused by high doses of intravenous applied bupivacaine., (© 2010 Blackwell Publishing Ltd.)

The incidence of retroperitoneal soft tissue sarcomas is with 0.1 to 0.2 percent very low. The tumors most often present as asymptomatic masses until the lesions are quite large, compared with the anatomic part, resulting in compression of nerves, vessels, bowel etc. The recommended management is the aggressive radical tumor excision including the pseudocapsule followed by a consequent clinical, ultrasonography and CT-scan follow-up. Tumor recurrences should be attempted in the same manner as primary tumors.