Clinical evaluation of cuff and tube tip position in a newly designed paediatric preformed oral cuffed tracheal tube

BACKGROUND

To assess the adequacy of the position of the tracheal tube cuff and tracheal tube tip in the recently introduced preformed oral Microcuff paediatric endotracheal tube (PET) using the manufacturers recommendations for Microcuff tracheal tube size selection.

METHODS

With Hospital Ethics Committee approval and informed parental consent, the tracheas of children from birth to adolescence were orally intubated with the preformed oral Microcuff PET. First, the position of the tracheal tube's intubation depth mark in relation to the vocal cords was assessed. Second, the distance 'tracheal tube tip-to-carina' was endoscopically measured with the patient supine and the head in a neutral position and the tube placed with the centre mark at the lower incisors or alveolar ridge.

RESULTS

A total of 166 children aged from 0.1 to 16.4 yr (median 5.9 yr) were studied. In five patients the intubation depth mark was above (5 mm each), in 22 patients at the level of and in the remaining 139 patients below the vocal cords. No endobronchial intubation occurred. In four patients the distance 'tracheal tube tip-to-carina' was smaller than the safety margin to prevent endobronchial intubation during head-neck flexion.

CONCLUSION

The new oral preformed cuffed tracheal tubes allow safe placement in almost all patients when inserted according to the tube bend. The critically low tube tip and the high cuff positions in a few tubes when placed according to the tube bend requires clinical alertness.

Intravenöse Midazolam-Ketamin-Anästhesie zur geschlossenen Reposition der Vorderarmfraktur bei Kindern

BACKGROUND

The aim of this study was to compare ketamine requirements in children undergoing closed reduction of forearm fractures under midazolam-ketamine anaesthesia with or without axillary plexus anaesthesia.

METHODS

With hospital ethical committee approval, we retrospectively analyzed the records of children who received midazolam-ketamine anaesthesia in the years 2000-2001 (group A) and midazolam-ketamine anaesthesia combined with axillary plexus anaesthesia in the years 2002-2004 (group B) for closed reduction of forearm fractures. Requirements for ketamine and postoperative analgesics were noted. Groups were compared with the Mann-Whitney U-test or T-test and the chi2-test (p<0.05).

RESULTS

A total of 455 children (group A 225/group B 230) were included in this study. The total amounts of ketamine were not statistically different between the two groups (p=0.154). However, ketamine requirements became less if the time interval between start of axillary plexus anaesthesia and start of intervention became more than 15 min (p<0.05). Patients in group B requested fewer analgesics in the postoperative period (p<0.01).

CONCLUSIONS

In the clinical routine of an emergency department the combination of midazolam-ketamine anaesthesia with axillary plexus anesthesia for closed reduction of forearm fractures in children did not result in lower requirements of ketamine.

Experimental infection of big brown bats (Eptesicus fuscus) with Eurasian bat lyssaviruses Aravan, Khujand, and Irkut virus

Here we describe the results of experimental infections of captive big brown bats (Eptesicus fuscus) with three newly isolated bat lyssaviruses from Eurasia (Aravan, Khujand, and Irkut viruses). Infection of E. fuscus was moderate (total, 55-75%). There was no evidence of transmission to in-contact cage mates. Incubation periods for Irkut virus infection were significantly shorter (p < 0.05) than for either Aravan or Khujand virus infections. In turn, quantification of viral RNA by TaqMan PCR suggests that the dynamics of Irkut virus infection may differ from those of Aravan/Khujand virus infection. Although infectious virus and viral RNA were detected in the brain of every rabid animal, dissemination to non-neuronal tissues was limited. Levels of viral RNA in brain of Aravan/Khujand virus-infected bats was significantly correlated with the number of other tissues positive by TaqMan PCR (p < 0.05), whereas no such relationship was observed for Irkut virus infection (where viral RNA was consistently detected in all tissues other than kidney). Infectious virus was isolated sporadically from salivary glands, and both infectious virus and viral RNA were obtained from oral swabs. The detection of viral RNA in oral swabs suggests that viral shedding in saliva occurred <5 days before the onset of clinical disease.

Evaluation of a new recommendation for improved cuffed tracheal tube size selection in infants and small children

BACKGROUND

The purpose of this study was to evaluate a new recommendation for tracheal tube size selection using second-generation Microcuff paediatric endotracheal tubes (PETs) with optimized outer diameter (OD) of the distal tube.

METHODS

With Ethics Committee approval, patients aged from birth to 5 years, requiring general anaesthesia with orotracheal intubation, were included. Tracheal tube sizes were selected as follows: internal diameter (ID) 3.0 mm, birth (if > or =3 kg) to <6 months; ID 3.5 mm, 6 to <18 months; ID 4.0 mm, 18 months to <3 years; ID 4.5 mm, 3 to <5 years. Tracheal tubes with the cuff not inflated were classified as too large if no air leak was obtained at an airway pressure of < or =20 cmH2O. Post-intubation stridor requiring therapy was noted.

RESULTS

Three hundred and fifty children were studied. Nine tracheal tubes (2.6%) were too large and had to be exchanged: in patients requiring tracheal tubes of ID 3.0 mm and 3.5 mm, three and four tracheal tubes, respectively, and, in patients requiring tracheal tubes of ID 4.0 mm and 4.5 mm, one tracheal tube in each group. In three patients (0.9%), post-intubation stridor occurred which required therapy.

CONCLUSION

The new recommendation presented for the use of second-generation Microcuff PETs with improved OD to ID ratio allows the selection of cuffed tracheal tubes with larger IDs than previously recommended for small children without increased need for tracheal tube exchange or increased incidence of post-intubation stridor in these age groups.

Improvement of herpetic stromal keratitis with fumaric acid derivate is associated with systemic induction of T helper 2 cytokines

Fumaric acid derivates have been shown to stimulate T helper-2-cytokines (interleukin (IL)-4, -5) without affecting the T-helper-1-cytokine (IL-2, interferon (IFN)-gamma)-response. Herein, the influence of systemic treatment with the fumaric acid derivate dimethylfumarate (DMF) on the secretion of T helper-cytokines and the development of HSV-1 stromal keratitis (HSK) was studied in mice. The corneas from BALB/c mice were infected with 10(5) PFU of HSV-1 (KOS strain). While one group of mice was treated intraperitoneally with PBS, another group of mice received DMF at 15 mg/kg of body weight. Expression of IL-2, -4, -10 and IFN-gamma was analysed in HSV-1 activated lymphocytes by ELISA. The severity of epithelial and stromal herpetic keratitis was investigated clinically. Corneas were studied for the inflammatory cell infiltration, and the CD3-, CD4- and CD8-positive cells were analysed by immunohistochemistry. The IL-2, -4, 10 and IFN-gamma content was measured in the corneas. Virus replication in the eyes was analysed by a plaque-assay. The DTH-response, the HSV-specific T cell proliferation and the serum neutralizing antibody-titres were investigated. DMF increased IL-4 and IL-10, but not IL-2 and IFN-gamma, secretion in activated lymphocytes from the spleen. Incidence and severity of stromal HSV-1 keratitis was reduced in the DMF group (P < 0.01). In the corneas from DMF-treated mice, the numbers of CD3+ and CD4+ cells were decreased and IL-4 was increased. Severity of epithelial disease and the virus-clearance from the eyes did not differ between the PBS and DMF group of mice. DTH, HSV-specific T cell proliferation and the neutralizing antibody-titres were not impaired. DMF increased the T helper-2-cytokine secretion in activated lymphocytes. After corneal HSV-1 infection, corneas from DMF treated mice had increased IL-4 content. This is associated with an improvement of herpetic stromal keratitis and reduced corneal T cell infiltration. DMF did not impair the systemic antiviral response.

Air leakage around endotracheal tube cuffs

BACKGROUND AND OBJECTIVE

To compare the recently introduced Microcuff endotracheal tube with conventional tubes in respect of the cuff pressures required to prevent air leakage.

METHODS

The following tubes (ID 7.0mm) were compared: Microcuff HVLP ICU, Mallinckrodt HiLo, Portex Profile Soft Seal, Rüsch Super Safety Clear and Sheridan CF. Fifty patients undergoing endotracheal intubation with a cuffed tube of internal diameter 7.0 mm were studied. Tracheas were intubated using one of the endotracheal tubes in random order. Cuff pressure to prevent air leakage at standardized ventilator setting (peak inspiratory pressure 20 cmH2O/PEEP 5 cmH2O/respiratory rate 15 breaths min(-1)) was assessed by auscultation of audible sounds at the mouth. Patients characteristics and cuff pressures from each brand were compared to the Microcuff group using the Mann-Whitney U-test (P < 0.05 was chosen as the level of statistical significance).

RESULTS

Patients' median age (range) was 14.2 (12.0-17.1) yr, body weight 57.5 (40.0-81.9) kg and length 164.9 (146.5-190.0) cm. No significant differences in patients' characteristics were found between groups. Mean cuff pressure (all tubes) required for air sealing was 19.1 (8-42) cmH2O. The Microcuff tube required significantly lower sealing pressures (9.5 (8-12) cmH2O) compared to the other brands of endotracheal tube (P < 0.05, Mann-Whitney U-test).

CONCLUSION

The Microcuff endotracheal tube with its ultra-thin polyurethane cuff membrane required the lowest sealing pressure to prevent air leakage. These features are potentially of interest for long-term intubated patients and for cuffed endotracheal tubes in children, allowing tracheal sealing at lower cuff pressures implying less damage to the trachea.

Synthesis and evaluation of fluorine-18 labeled glyburide analogs as beta-cell imaging agents

Glyburide is a prescribed hypoglycemic drug for the treatment of type 2 diabetic patients. We have synthesized two of its analogs, namely N-[4-[beta-(2-(2'-fluoroethoxy)-5-chlorobenzenecarboxamido)ethyl]benzenesulfonyl]-N'-cyclohexylurea (2-fluoroethoxyglyburide, 8b) and N-[4-[beta-(2-(2'-fluoroethoxy)-5-iodobenzenecarboxamido)ethyl]benzenesulfonyl]-N'-cyclohexylurea (2-fluoroethoxy-5-deschloro-5-iodoglyburide, 8a), and their fluorine-18 labeled analogs as beta-cell imaging agents. Both F-18 labeled compound 8a and compound 8b were synthesized by alkylation of the corresponding multistep synthesized hydroxy precursor 4a and 4b with 2-[(18)F]fluoroethyl tosylate in DMSO at 120 degrees C for 20 minutes followed by HPLC purification in an overall radiochemical yield of 5-10% with a synthesis time of 100 minutes from EOB. The octanol/water partition coefficients of compounds 8a and 8b were 141.21 +/- 27.77 (n = 8) and 124.33 +/- 21.61 (n = 8), respectively. Insulin secretion experiments of compounds 8a and 8b on rat islets showed that both compounds have a similar stimulating effect on insulin secretion as that of glyburide. In vitro binding studies showed that approximately 2% of compounds 8a and 8b bound to beta TC3 and Min6 cells and that the binding was saturable. Preliminary biodistribution studies in mice showed that the uptake of both compounds 8a and 8b in liver and small intestine were high, whereas the uptake in other organs studied including pancreas were low. Additionally, the uptake of compound 8b in vivo was nonsaturable. These results tend to suggest that compounds 8a and 8b may not be the ideal beta-cell imaging agents.

Use of high resolution digital thermography to detect Heterodera schachtii infestation in sugar beets

Thermography is a non-destructive method used to monitor pest and disease infestations, as it is related to changes in plant water status. Surface temperature differences of the crop canopy may be an indicator of nematode infestation as the parasitation of the root system reduces evaporation of leaves. To test the potential of high resolution digital thermography to detect Heterodera schachtii infestation, experiments using increasing nematode densities and different sugar beet varieties were conducted. From June to August 2003 the crop canopy temperature was measured with a thermal infrared camera from a helicopter. A significant correlation between canopy temperature and nematode density was observed with the susceptible cultivar Monza whereas the resistant cultivar Paulina did not show any correlation. Mean temperature comparison showed significant differences between the lowest infestation level (500 eggs and larvae/100 ml soil) and the highest infestation level (>1500 eggs and larvae/100 ml soil). At the beginning of the season canopy temperature differences between healthy and nematode infested sugar beets were higher (approximately 1 degree C) compared to later assessment dates when the water supply in the soil was limited. Since low and high nematode infestation could be clearly distinguished with the susceptible cultivar by airborne thermal images, thermography might be a useful tool for monitoring sugar beet fields.

Remifentanil-propofol versus sufentanil-propofol anaesthesia for supratentorial craniotomy: a randomized trial

BACKGROUND AND OBJECTIVE

Remifentanil has unique pharmacokinetics that might allow faster recovery after neurosurgery. We investigated the effects of a propofol/sufentanil versus a remifentanil/propofol regimen on the primary end-point tracheal extubation time.

METHODS

In the Neurosurgery Department of a University Hospital, 36 patients awaiting craniotomy for supratentorial tumour resection were randomly assigned to one of two study groups. In the sufentanil/propofol group, anaesthesia was induced with 0.5 microg kg(-1) sufentanil and 1-2 mg kg(-1) propofol. Propofol infusion and boluses of sufentanil were administered for maintenance. In the remifentanil/propofol group, anaesthesia was started with an infusion of remifentanil (0.2-0.35 microg kg(-1) min(-1)) and a bolus of propofol (1.5-2 mg kg(-1)). Patients received a propofol infusion and a remifentanil infusion for maintenance of anaesthesia. Recovery times were taken from cessation of the propofol infusion. In addition, data about self-reported nausea and vomiting, pain and analgesic requirements were collected.

RESULTS

Patients in the remifentanil/propofol group were extubated earlier (mean times 6.4 (+/- SD 4.7) versus 14.3 (+/- 9.2) min; P = 0.003). The two groups were similar with respect to postoperative nausea and vomiting, and patient-reported pain scores. Fifty per cent of the remifentanil/propofol patients and 88% of the sufentanil/propofol patients required no analgesics within 1 h after operation (P = 0.03).

CONCLUSIONS

The remifentanil/propofol regimen provided quicker recovery. The two regimens were similar in terms of postoperative nausea and vomiting and patient-reported pain scores, but patients in the remifentanil/ propofol group required more analgesics within 1 h postoperatively.

Five-year follow-up of intermittent distracting rod correction in congenital scoliosis

Severe progressive curve deformities in children's congenital scoliosis often require an early operative intervention. As spinal fusion interferes with longitudinal growth, a "growth enabling" operative device may represent an alternative method to delay a progressive curve deformity until an eventual operative intervention can be carried out. We report on the five-year follow-up of a seven-year-old girl who presented at our clinic with severe congenital scoliosis of 62 degrees with a unilateral unsegmented bar between T7 and T12 and an anomaly of segmentation between L2 and L4. An intermittent distracting rod was implanted with transpedicular fixation from T3/T5 to L3/L4. The correction was obtained by distraction of the mobile segments and also by hemiepiphyseodesis between L2 and L4. The rod's longitudinal extension could be distracted using a special thread. Three successive operations to obtain a minimal access to the thread were necessary to achieve a correction to an angle of 30 degrees with a total rod distraction of 4.5 cm.

[Extranodale lymphomas infradiaphragmal]

Non-Hodgkin's lymphoma occurs in up to 30% primarily out of lymph nodes (extranodal). In the abdomen, beside spleen and liver the gastrointestinal tract is often and the kidneys are not rarely affected. However, each abdominal organ and peritoneal space, muscles and skin can be affected at various frequencies. While an exclusive manifestation within an organ without lymphadenopathy is rather unusual, often a concomitant lymphadenopathy is present. A secondary infiltration of an organ due to widespread lymphoma,hematogenous spread or relapse occurs more frequently. On the other hand, in Hodgkin's lymphoma, except spleen and liver other organs are only rarely affected. Mostly it occurs by direct invasion from adjacent pathological lymph nodes.Frequency, morphology at and problems of imaging of extranodal lymphoma are presented.

Remifentanil-clonidine-propofol versus sufentanil-propofol anesthesia for coronary artery bypass surgery

OBJECTIVE

To compare a remifentanil-clonidine-propofol regimen with conventional sufentanil-propofol anesthesia.

DESIGN

Randomized, nonblinded trial.

SETTING

A single university hospital.

PARTICIPANTS

Male patients scheduled for coronary artery bypass graft (CABG) surgery.

INTERVENTIONS

In the control group, anesthesia was induced with 0.5 microg/kg of sufentanil and 0.2 to 0.3 mg/kg of etomidate after preoxygenation. Propofol (50 to 100 microg/kg/min) and sufentanil (0.5 to 1.0 microg/kg/h) were started after endotracheal intubation. Sufentanil was stopped after aortic decannulation. In the remifentanil-clonidine group, anesthesia was started with remifentanil (0.15 to 0.3 microg/kg/min), followed by etomidate (0.2 to 0.3 mg/kg). Propofol was started at 50 to 100 microg/kg/min, and after endotracheal intubation, clonidine infusion was started (6 to 20 microg/h). Patients received piritramide (0.15 mg/kg) and metamizole (20 mg/kg) for transitional analgesia. In both groups, propofol infusion was reduced to 30 to 60 microg/kg/min at skin closure and stopped when assisted spontaneous breathing led to adequate gas exchange.

MEASUREMENTS AND MAIN RESULTS

The main outcomes were recovery times; somatic variables; plasma catecholamine levels; and self-recorded pain, nausea, and vomiting. Patients in the remifentanil-clonidine group were extubated earlier and had lower plasma epinephrine and norepinephrine levels. After transitional analgesia, the remifentanil-clonidine patients had similar postoperative analgesic use and self-reported pain and side-effect scores.

CONCLUSION

Compared with a sufentanil-propofol regimen, an anesthetic regimen for CABG surgery that combines remifentanil, clonidine, and propofol provides similar hemodynamics. The remifentanil-clonidine regimen reduces catecholamine levels and hastens recovery from anesthesia.

[Anthropometric 3D-body scanning in idiopathic scoliosis]

PURPOSE

A new, non-invasive method of 3D-measurement is presented which allows the spatial recording of the entire body surface in scoliotic deformities. The application of the system is examined to raise automatically anthropometric data of patients with scoliosis.

METHOD

32 patients with idiopathic scoliosis were examined (average age 15.3 years, 25 girls and 7 boys, Cobb angles between 11 and 72 degrees). The whole body recording is carried out with a 3D laser scanner. During the measuring process the patient is standing in a frame. Within the measuring time of 15 seconds the body surface is registered by lasers and four cameras. The measured values are converted to a digital 3D model. The resolution is up to 1 mm. On the digital 3D model an automatic calculation of defined anthropometric parameters were carried out. Each patient was measured twice.

RESULTS

In all patients a virtual 3D model with a high surface accuracy was obtained. Was the model the typical body asymmetries in scoliotic deformities were visible. The automatic calculation shows a mean deviation of the second measurements between 0.23 and 0.71 cm. The reproducibility depended on the type of the measured parameters.

CONCLUSIONS

The laser scanning system allows a rapid, touchless and accurate 3D measurement of the whole body in scoliotic deformities. To determine anthropometric parameters the reproducibility of the automatic calculation is sufficient in most parameters.