Stress hyperglycaemia following trauma - a survival benefit or an outcome detriment?

PURPOSE OF REVIEW: Stress hyperglycaemia occur often in critically injured patients. To gain new consideration about it, this review compile current as well as known immunological and biochemical findings about causes and emergence. RECENT FINDINGS: Glucose is the preferred energy substrate for fending immune cells, reparative tissue and the cardiovascular system following trauma. To fulfil these energy needs, the liver is metabolically reprogrammed to rebuild glucose from lactate and glucogenic amino acids (hepatic insulin resistance) at the expenses of muscles mass and - to a less extent - fat tissue (proteolysis, lipolysis, peripheral insulin resistance). This inevitably leads to stress hyperglycaemia, which is evolutionary preserved and seems to be an essential and beneficial survival response. It is initiated by damage-associated molecular patterns (DAMPs) and pathogen-associated molecular patterns (PAMPs), intensified by immune cells itself and mainly ruled by tumour necrosis factor (TNF)α and catecholamines with lactate and hypoxia inducible factor (HIF)-1α as intracellular signals and lactate as an energy shuttle. Important biochemical mechanisms involved in this response are the Warburg effect as an efficient metabolic shortcut and the extended Cori cycle. SUMMARY: Stress hyperglycaemia is beneficial in an acute life-threatening situation, but further research is necessary, to prevent trauma patients from the detrimental effects of persisting hyperglycaemia.

Absence of Stress Hyperglycemia Indicates the Most Severe Form of Blunt Liver Trauma.

BACKGROUND: Stress hyperglycemia is common in trauma patients. Increasing injury severity and hemorrhage trigger hepatic gluconeogenesis, glycogenolysis, peripheral and hepatic insulin resistance. Consequently, we expect glucose levels to rise with injury severity in liver, kidney and spleen injuries. In contrast, we hypothesized that in the most severe form of blunt liver injury, stress hyperglycemia may be absent despite critical injury and hemorrhage. METHODS: All patients with documented liver, kidney or spleen injuries, treated at a university hospital between 2000 and 2020 were charted. Demographic, laboratory, radiological, surgical and other data were analyzed. RESULTS: A total of 772 patients were included. In liver (n = 456), spleen (n = 375) and kidney (n = 152) trauma, an increase in injury severity past moderate to severe (according to the American Association for the Surgery of Trauma, AAST III-IV) was associated with a concomitant rise in blood glucose levels independent of the affected organ. While stress-induced hyperglycemia was even more pronounced in the most severe forms (AAST V) of spleen (median 10.7 mmol/L, p < 0.0001) and kidney injuries (median 10.6 mmol/L, p = 0.004), it was absent in AAST V liver injuries, where median blood glucose level even fell (5.6 mmol/L, p < 0.0001). CONCLUSIONS: Absence of stress hyperglycemia on hospital admission could be a sign of most severe liver injury (AAST V). Blood glucose should be considered an additional diagnostic criterion for grading liver injury.

Validation of the revised 2018 AAST-OIS classification and the CT severity index for prediction of operative management and survival in patients with blunt spleen and liver injuries.

OBJECTIVES: Non-operative management (NOM) is increasingly utilised in blunt abdominal trauma. The 1994 American Association of Surgery of Trauma grading (1994-AAST) is applied for clinical decision-making in many institutions. Recently, classifications incorporating contrast extravasation such as the CT severity index (CTSI) and 2018 update of the liver and spleen AAST were proposed to predict outcome and guide treatment, but validation is pending. METHODS: CT images of patients admitted 2000-2016 with blunt splenic and hepatic injury were systematically re-evaluated for 1994/2018-AAST and CTSI grading. Diagnostic accuracy, diagnostic odds ratio (DOR), and positive and negative predictive values were calculated for prediction of in-hospital mortality. Correlation with treatment strategy was assessed by Cramer V statistics. RESULTS: Seven hundred and three patients were analysed, 271 with splenic, 352 with hepatic and 80 with hepatosplenic injury. Primary NOM was applied in 83% of patients; mortality was 4.8%. Comparing prediction of mortality in mild and severe splenic injuries, the CTSI (3.1% vs. 10.3%; diagnostic accuracy = 75.4%; DOR = 3.66; p = 0.006) and 1994-AAST (3.3% vs. 10.5%; diagnostic accuracy = 77.9%; DOR = 3.45; p = 0.010) were more accurate compared with the 2018-AAST (3.4% vs. 8%; diagnostic accuracy = 68.2%; DOR = 2.50; p = 0.059). In hepatic injuries, the CTSI was superior to both AAST classifications in terms of diagnostic accuracy (88.7% vs. 77.1% and 77.3%, respectively). CTSI and 2018-AAST correlated better with the need for surgery in severe vs. mild hepatic (Cramer V = 0.464 and 0.498) and splenic injuries (Cramer V = 0.273 and 0.293) compared with 1994-AAST (Cramer V = 0.389 and 0.255; all p < 0.001). CONCLUSIONS: The 2018-AAST and CTSI are superior to the 1994-AAST in correlation with operative treatment in splenic and hepatic trauma. The CTSI outperforms the 2018-AAST in mortality prediction. KEY POINTS: • Non-operative management of blunt abdominal trauma is increasingly applied and correct patient stratification is crucial. • CT-based scoring systems are used to assess injury severity and guide clinical decision-making, whereby the 1994 version of the American Association of Surgery of Trauma Organ Injury Scale (AAST-OIS) is currently most commonly utilised. • Including contrast media extravasation in CT-based grading improves management and outcome prediction. While the 2018-AAST classification and the CT-severity-index (CTSI) better correlate with need for surgery compared to the 1994-AAST, the CTSI is superior in outcome-prediction to the 2018-AAST.

Non-operative management of blunt hepatic and splenic injury: a time-trend and outcome analysis over a period of 17 years.

Background: A widespread shift to non-operative management (NOM) for blunt hepatic and splenic injuries has been observed in most centers worldwide. Furthermore, many countries introduced safety measures to systematically reduce severe traffic and leisure sports injuries. This study aims to evaluate the effect of these nationwide implementations on individual patient characteristics and outcomes through a time-trend analysis over 17 years in an Austrian high-volume trauma center. Methods: A retrospective review of all emergency trauma patients admitted to the Medical University of Innsbruck from 2000 to 2016. Injury severity, clinical data on admission, operative and non-operative treatment parameters, complications, and in-hospital mortality were evaluated. Results: In total, 731 patients were treated with blunt hepatic and/or splenic injuries. Among these, 368 had a liver injury, 280 splenic injury, and 83 combined hepatic/splenic injury. Initial NOM was performed in 82.6% of all patients (93.5% in hepatic and 71.8% in splenic injuries) with a success rate of 96.7%. The secondary failure rate of NOM was 3.3% and remained consistent over 17 years (p = 0.515). In terms of injury severity, we observed a reduction over time, resulting in an overall mortality rate of 4.8% and 3.5% in the NOM group (decreasing from 7.5 to 1.9% and from 5.6 to 1.3%, respectively). These outcomes confirmed an improved utilization of the NOM approach. Conclusion: Our cohort represents one of the largest Central European single-center experiences available in the literature. NOM is the standard of care for blunt hepatic and splenic injuries and successful in > 96% of all patients. This rate was quite constant over 17 years (p = 0.515). Overall, national and regional safety measures resulted in a significantly decreased severity of observed injury patterns and deaths due to blunt hepatic or splenic trauma. Although surgery is nowadays only applied in about one third of splenic injury patients in our center, these numbers might further decrease by intensified application of interventional radiology and modern coagulation management.

Aortic stent graft placement under extracorporeal membrane oxygenation in severe multiple trauma.

Placement of an aortic stent graft under extracorporeal membrane oxygenation was the life-saving procedure in a case of severe head trauma and traumatic aortic dissection after injured by a railroad engine. Timely access to neurosurgery, heart surgery, and radiology providing minimal invasive interventions increase the chances of a favorable outcome.

Short- versus long-term complementary nutritional support via needle catheter jejunostomy after pancreaticoduodenectomy: Study protocol of a randomized controlled trial.

INTRODUCTION: Pancreatic resection is the only curative treatment for pancreatic cancer. Due to tumor cachexia most patients present with a weight loss at the time of diagnosis. Postoperatively the weight loss is often intensified. Tumor cachexia has an influence on the post-operative morbidity and mortality and on the overall survival. Complementary nutrition has a benefit on the mentioned issues. Needle catheter jejunostomy (NCJ) offers a well-tolerated and safe way for additional nutrition therapy. Until today, the optimal length of postoperative supplementary nutrition has not been evaluated. METHODS AND ANALYSIS: The study is designed as a randomized controlled trial to compare the effect of complementary nutritional support until discharge and until 8-weeks after discharge for patients after pancreaticoduodenectomy (PD). The primary endpoint is the comprehensive complications index assessed 12 weeks postoperatively. The grading of the complications will be performed by a blinded assessor. The secondary endpoints are: quality of life, a nutritional assessment and the assessment of the effect on adjuvant therapies and 5-year survival. Follow-up visits are planned 1-, 3-, 6-, 12- and 60 month postoperatively. A total sample size of 140 patients was determined for the analysis of the primary endpoint. The confirmatory analysis will be performed based on the intention-to-treat principle. ETHICS AND DISSEMINATION: The ethics committee of the University of Bern reviewed and approved this study on 22.08.2016 (KEK BE 322/14). The trial was registered in the German Clinical Trial Register (DRKS00010237) on 25.08 2016. The present trial is the first study comparing short- and long-term complementary nutritional support after PD in randomized controlled study. The results will allow a postoperative nutritional therapy after PD based on high quality data. The results will be presented at relevant surgical conferences and written publications of the short-term results and long-term oncologic results are planned within surgical journals.

Case-matched study of lesser versus greater curvature approach in laparoscopic Warshaw pancreatectomy.

BACKGROUND: In laparoscopic distal pancreatectomy (LapDP), the pancreas is accessed in a greater curvature approach (GCA). The lesser curvature approach (LCA) has been proposed in underweight patients. The study investigated the feasibility of LCA irrespective of the body mass index (BMI). METHODS: This retrospective study included consecutive patients scheduled to undergo LapDP with the LCA. A matched cohort (1:1) underwent GCA. Spleen preservation was performed using the Warshaw technique. Splenic perfusion was intraoperatively assessed by indocyanine green (ICG) angiography. RESULTS: The LCA with LapDP was successful in 12/15 patients. In 2 cases, LCA had to be converted to GCA and in 1 patient to open surgery. The cohorts were well matched in sex (P = 1.0), age (P = .67), indication (P = 1.0), and median BMI (23.4 kg/m2 vs 24.8 kg/m2, P = .41). Splenic preservation was achieved in 14/15 patients with LCA and 4/15 patients with GCA (P = .33). In all LCA cases, ICG angiography indicated sufficient spleen perfusion. The groups had similar morbidity (P = 1.0) and hospital stay (P = .74). CONCLUSIONS: LCA was feasible in 80% irrespective of BMI and provided an excellent field of exposure. ICG angiography was feasible in the Warshaw technique. Its reliability should be evaluated in prospective studies.

Stair climbing - an insight and comparison between women with and without joint hypermobility: a descriptive study.

Generalized joint hypermobility (GJH) is a frequent entity in rheumatology with higher prevalence among women. It is associated with chronic widespread pain, joint dislocations, arthralgia, fibromyalgia and early osteoarthritis. Stair climbing is an important functional task and can induce symptoms in hypermobile persons. The aim of this study was to compare ground reaction forces (GRF) and muscle activity during stair climbing in women with and without GJH. A cross-sectional study of 67 women with normal mobility and 128 hypermobile women was performed. The hypermobile women were further divided into 56 symptomatic and 47 asymptomatic. GRFs were measured by force plates embedded in a six step staircase, as well as surface electromyography (EMG) of six leg muscles. Parameters derived from GRF and EMG were compared between groups using t-test and ANOVA. For GRF no significant differences were found. EMG showed lower activity for the quadriceps during ascent and lower activity for hamstrings and quadriceps during descent in hypermobile women. For symptomatic hypermobile women these differences were even more accentuated. The differences in EMG may point towards an altered movement pattern during stair climbing, aimed at avoiding high muscle activation. However, differences were small, since stair climbing seems to be not demanding.

Histologic pathologies of the myocardium in septic shock: a prospective observational study.

Myocardial depression in septic shock is well known, but its pathophysiological genesis is incompletely understood. To assess the incidence and extent of stress-induced histologic myocardial alterations in septic shock, a prospective, observational, combined clinical and postmortem study was conducted, and 20 patients dying from septic shock were included. Exclusion criteria were younger than 18 years, pregnancy, open heart surgery or cardiopulmonary resuscitation, acute neurologic diseases, pheochromocytoma, and forensic autopsy. A systematic macropathologic evaluation was performed. Nine predefined heart sections were histologically screened for myocytolysis, interstitial fibrosis, contraction band necrosis, mononuclear infiltrates, interstitial edema, and tissue hemorrhage. Stress-induced pathologies were found in 90% to 100% of patients in all heart sections (myocytolysis, 100%; interstitial fibrosis, 100%; contraction band necrosis, 95%; mononuclear infiltrates, 90%; interstitial edema, 90%; tissue hemorrhage, 30%). The incidence and extent of contraction band necrosis, mononuclear infiltrates, and myocytolysis did not differ between sexes; patients with or without chronic ß-blocker, calcium antagonist, and/or statin premedication; or between the binary use of different catecholamine agents (all comparisons P > 0.05). The maximum epinephrine dose correlated with the overall extent of mononuclear infiltrates (Spearman-Rho, r = 0.704; P = 0.05) and myocytolysis (Spearman-Rho, r = 0.933; P = 0.001). Maximum norepinephrine doses correlated with the extent of mononuclear infiltrates in the left ventricular anterior wall (Spearman-Rho, r = 0.519; P = 0.02). The total duration of catecholamine therapy was correlated with the extent of mononuclear infiltrates in the apex (Spearman-Rho, r = 0.571; P = 0.009) and right atrium (Spearman-Rho, r = 0.535; P = 0.02). In conclusion, our results suggest that histologic lesions potentially indicative of stress-induced cardiotoxicity can be observed in most patients dying from septic shock.

Microstructure and electronic band structure of pulsed laser deposited iron fluoride thin film for battery electrodes.

Battery electrodes in thin-film form are free of the binders used with traditional powder electrodes and present an ideal platform to obtain basic insight to the evolution of the electrode-electrolyte interface passivation layer, the formation of secondary phases, and the structural underpinnings of reversibility. This is particularly relevant to the not yet fully understood conversion electrode materials, which possess enormous potential for providing transformative capacity improvements in next-generation lithium-ion batteries. However, this necessitates an understanding of the electronic charge transport properties and band structure of the thin films. This work presents an investigation of the electron transport properties of iron fluoride (FeF2) thin-film electrodes for Li-ion batteries. FeF2 thin films were prepared by pulsed-laser deposition, and their phase purity was characterized by electron microscopy and diffraction. The grown materials are polycrystalline FeF2 with a P42/mnm crystallographic symmetry. Room-temperature Hall measurements reveal that as-deposited FeF2 is n-type: the Hall coefficients were negative, electron mobility was 0.33 cm2/(V s) and resistivity was 0.255 Ω cm. The electronic band diagram of FeF2 was obtained using a combination of ultraviolet photoelectron spectroscopy, photoluminescence, photoluminescence excitation and optical absorption, which revealed that FeF2 is a direct bandgap, n-type semiconductor whose band structure is characterized by a 3.4 eV bandgap, a workfunction of ∼4.51 eV, and an effective Fermi level that resides approximately 0.22 eV below the conduction band edge. We propose that the shallow donor levels at 0.22 eV are responsible for the measured n-type conductivity. The band diagram was used to understand electron transport in FeF2 thin film and FeF2-C composite electrodes.

Utility of PCR in diagnosis of invasive fungal infections: real-life data from a multicenter study.

Prospective studies addressing the clinical value of broad-range PCR using the internal transcribed spacer region (ITS) for diagnosis of microscopy-negative fungal infections in nonselected patient populations are lacking. We first assessed the diagnostic performance of ITS rRNA gene PCR compared with that of routine microscopic immunofluorescence examination. Second, we addressed prospectively the impact and clinical value of broad-range PCR for the diagnosis of infections using samples that tested negative by routine microscopy; the corresponding patients' data were evaluated by detailed medical record reviews. Results from 371 specimens showed a high concordance of >80% for broad-range PCR and routine conventional methods, indicating that the diagnostic performance of PCR for fungal infections is comparable to that of microscopy, which is currently considered part of the "gold standard." In this prospective study, 206 specimens with a negative result on routine microscopy were analyzed with PCR, and patients' clinical data were reviewed according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group. We found that broad-range PCR showed a sensitivity, specificity, positive predictive value, and negative predictive value of 57.1%, 97.0%, 80%, and 91.7%, respectively, for microscopy-negative fungal infections. This study defines a possible helpful role of broad-range PCR for diagnosis of microscopy-negative fungal infections in conjunction with other tests.

Single ion as a three-body reaction center in an ultracold atomic gas.

We report on three-body recombination of a single trapped Rb(+) ion and two neutral Rb atoms in an ultracold atom cloud. We observe that the corresponding rate coefficient K(3) depends on collision energy and is about a factor of 1000 larger than for three colliding neutral Rb atoms. In the three-body recombination process large energies up to several 0.1 eV are released leading to an ejection of the ion from the atom cloud. It is sympathetically recooled back into the cloud via elastic binary collisions with cold atoms. Further, we find that the final ionic product of the three-body processes is again an atomic Rb(+) ion suggesting that the ion merely acts as a catalyzer, possibly in the formation of deeply bound Rb(2) molecules.

Morbidity rate of reoperation in thyroid surgery: a different point of view.

BACKGROUND: Goitre recurrence is a common problem following subtotal thyroid gland resection for multinodular goitre disease. The aim of the present study was to evaluate morbidity rate in relation to the side of initial and redo-surgery for recurrent disease. METHODS: A total of 1699 patients underwent consecutive thyroid gland surgery between 1997 and 2010 at our institution. One hundred and eighteen patients (6.9%) underwent redo-surgery for recurrent disease after subtotal resection. One hundred and nine patients with complete follow-up were included in the present study. RESULTS: Recurrent disease was found in 79 patients (72.5%) in the ipsilateral lobe and in 30 patients (27.5%) in the contralateral lobe. The incidence of permanent recurrent laryngeal nerve palsy was significantly higher in patients undergoing redo-surgery on the ipsilateral lobe compared to patients undergoing initial operation (3.8% vs. 1.1%; p = 0.03), whereas no difference was found in patients with contralateral redo-surgery compared to patients undergoing initial operation (p = 1.0). Independent risk factors for contralateral recurrent disease were age at primary operation <37 years (OR 4.86; 95% CI 1.58-15.01) and time to recurrence <20 years (OR 6.53; 95% CI 2.23-19.01). CONCLUSION: Morbidity rate for recurrent disease after subtotal resection was significantly higher for ipsilateral redo-surgery compared to initial surgery, whereas redo-surgery can be performed safely on the contralateral lobe. Young age at primary operation and short time to recurrence are independent risk factors for contralateral recurrent disease.

Impact of surgical technique on operative morbidity and its socioeconomic benefit in thyroid surgery.

PURPOSE: The aim of this retrospective cohort study was to evaluate the rate of complications in relation to the extent of surgery and some of its consequences. METHODS: Between 1972 and 2010, a total of 5,277 consecutive thyroid gland surgeries with 7,383 nerves at risk were performed at our teaching institution. Data of all patients undergoing thyroidectomy were collected prospectively. A total of 2,867 subtotal resections (first study period from 1972 to 1990) were compared with 2,410 extended thyroid resections involving at least a hemithyroidectomy (second period from 1991 to 2010). RESULTS: The incidence of permanent recurrent laryngeal nerve palsy in primary operations was significantly higher in the first period compared to the second period (3.6 vs. 0.9 %; p < 0.001). Permanent hypoparathyroidism decreased from 3.2 % in the first period to 0.8 % in the second period (p < 0.001). The incidence of recurrent goiter surgery decreased from 11.1 % in the first period to 8.1 % in the second period (p < 0.001). No significant difference was found in permanent recurrent laryngeal nerve palsy in recurrent disease between the two periods. The socioeconomic benefits of an extended thyroid resection in our patient population are 360 preventable operations, 90 preventable permanent recurrent laryngeal nerve palsies, and 58 preventable cancers. Furthermore, 37 preventable radioiodine ablations and 15 preventable deaths were associated with more radical thyroid resection. CONCLUSION: Improvements in surgical technique and change in surgical strategy significantly decreased the prevalence of recurrent laryngeal nerve palsy, hypoparathyroidism, and recurrent disease as well as reduced public health costs associated with recurrent goiter.

An apparatus for immersing trapped ions into an ultracold gas of neutral atoms.

We describe a hybrid vacuum system in which a single ion or a well-defined small number of trapped ions (in our case Ba(+) or Rb(+)) can be immersed into a cloud of ultracold neutral atoms (in our case Rb). This apparatus allows for the study of collisions and interactions between atoms and ions in the ultracold regime. Our setup is a combination of a Bose-Einstein condensation apparatus and a linear Paul trap. The main design feature of the apparatus is to first separate the production locations for the ion and the ultracold atoms and then to bring the two species together. This scheme has advantages in terms of stability and available access to the region where the atom-ion collision experiments are carried out. The ion and the atoms are brought together using a moving one-dimensional optical lattice transport which vertically lifts the atomic sample over a distance of 30 cm from its production chamber into the center of the Paul trap in another chamber. We present techniques to detect and control the relative position between the ion and the atom cloud.

Multidisciplinary Approach to Lifesaving Measures in the Elderly Individuals With Flail Chest Injury With ORIF of Rib Fractures: A Report of 2 Cases.

In this case report, we present 2 cases of flail chest in geriatric patients after severe blunt chest trauma, which were treated at the University Hospital Innsbruck (Level I Trauma Center and Tyrolean Geriatric Fracture Center) by a multidisciplinary team of physicians from anesthesia, intensive care, trauma surgery, and acute geriatrics. We want to point out the benefit of a multidisciplinary approach in geriatric patients with flail chest.

Contribution of liquid-phase and gas-phase ionization in extractive electrospray ionization mass spectrometry of primary amines.

In this study, we investigated how binary mixtures of compounds influence each other's signal intensity in electrospray ionization (ESI), extractive electrospray ionization (EESI) and secondary electrospray ionization (SESI) experiments. The experiments were conducted using a series of homologous primary amines (from 1-butyl to 1- decylamine). In every experiment, two of the amines were present, and all 21 possible combinations were measured with EESI, ESI and SESI as ionization sources. Except for the volatility, which decreases with increasing molecular weight, the physico-chemical properties of the amines are very similar, so that the intensity ratio obtained in each experiment provides information about discrimination effects occurring during the ionization process. The results show that for the relatively volatile compounds investigated, the EESI ionization mechanism resembles the SESI-like gas-phase charge transfer more than ESI-like analyte ionization in solution. In addition, almost no discrimination effects were observed in the spectra obtained in EESI experiments. Quantitative EESI experiments with nonylamine as internal standard showed that EESI is capable of providing both more accurate and more precise results than SESI and ESI.

Electrosonic spray ionization--an ideal interface for high-flow liquid chromatography applications.

Electrosonic spray ionization (ESSI) has been studied as an interface between high-performance liquid chromatography (HPLC) and mass spectrometry (MS), using sample flow rates up to 3.0 ml min⁻¹. This ionization interface was compared with pneumatically assisted electrospray ionization (ESI) using mass spectrometry for detection. For experiments that did not involve direct comparison of different flow rates, the ESI experiments were performed using post column splitting to work at optimal conditions. ESSI allows the interfacing of conventional or high-resolution liquid chromatography (LC) methods to mass spectrometry without post column splitting. High sample flow rates could be handled without a significant loss of signal intensity using a nebulization gas flow rate of 5.5 L min⁻¹. Since ESI needs to be operated with lower sample flow rates, it is limited to micro/nano LC systems, or post column splitting must be used. In particular, nano LC systems have to be treated with great care and require constant maintenance. When using post-column splitting, the increased diffusion can become a problem especially when using systems with very small void volumes. In all experiments ESSI showed better signal intensities than a commercially available, pneumatically assisted ESI source. ESSI does not require heating of the nebulizer gas, which should help to preserve the original structure of thermally unstable molecules. Therefore, ESSI is presented as an alternative to the commercially available heated ESI sources of AB SCIEX, Thermo Fischer, Agilent and Waters. The observed LC-ESSI-MS ion chromatograms are shown to be very stable even when using flow rates higher than 1.0 ml min⁻¹, which could be very suitable for ultra high performance LC, where sample flow rates up to 2.0 mL min⁻¹ with backpressures up to 1200 bar are used. Also, a difference in the relative intensities of singly and doubly protonated peptide monomers and dimers was observed between the two ionization methods. The coefficients of determination for the calibration of instrument response for Val-Tyr-Val and Met-Enkephalin showed excellent linearity over a wide concentration range (0.1-100 µM), while ESI results were only linear over a much smaller range (0.1-20 µM). The observed behavior is thought to be caused by insufficient ionization efficiency of solutions above ∼20 µM by ESI, exemplifying the robustness of ESSI as an interface between LC and MS.

Intrathyroid adenomas in primary hyperparathyroidism: are they frequent enough to guide surgical strategy?

BACKGROUND: Ectopic parathyroid adenoma, including intrathyroid adenoma, is a common cause of failed parathyroid operations. The aim of this study was to evaluate the operative strategy/outcome in patients with primary hyperparathyroidism (pHPT), with special regard to intrathyroid adenomas. METHOD: The authors performed an analysis of all patients receiving operative treatment for pHPT from 2003 through 2005. The operative strategy consisted of systematic perithyroid exploration followed by extended cervical exploration in cases where the adenoma was not found initially. In cases of persistent, high intraoperative parathyroid hormone levels, hemithyroidectomy was performed on the side with higher suspicion of intrathyroid adenoma or with more extended thyroid changes. RESULTS: During the study, 115 patients received surgical treatment for sporadic pHPT. A single parathyroid adenoma (normal parathyroid position) was found in 95 patients (82.6%), ectopic single adenoma was found in 7 patients (6.1%), and double adenomas were found in 10 (8.7%) patients. Operative failure occurred in 3 cases (2.6%). In all, 4 of 7 ectopic single adenomas were intrathyroidal and were removed by hemithyroidectomy according to the authors' standard protocol. CONCLUSION: The strategy of (a) cervical exploration, (b) extended cervical exploration, and (c) hemithyroidectomy was highly successful for removing undetectable intrathyroid parathyroid adenomas during primary intervention, thereby reducing the risks associated with reintervention.