The added value of brain MR spectroscopy in children with Crigler-Najjar syndrome type-I: correlation with demographic, neurodevelopmental, and laboratory findings.

OBJECTIVE: The aim of this study is to demonstrate the role of proton magnetic resonance spectroscopy (1H-MRS) in the detection of brain microstructural changes in patients with Crigler-Najjar syndrome type-I (CNs-I), and its correlation with demographic, neurodevelopmental and laboratory findings. METHODS: Prospective study was conducted on 25 children with CNs-I and 25 age and sex-matched children, who served as control. They underwent multivoxel 1H-MRS of basal ganglion at echo time 135-144 ms. N-acetyl aspartate/Creatine (NAA/Cr) and Choline (Ch)/Cr were calculated and correlated with demographic, clinical, and laboratory findings of patients with CNs-I. RESULTS: There was a significant difference in NAA/Cr and Ch/Cr between patients and controls. The cut-off value for NAA/Cr and Ch/Cr used to differentiate patients from controls were 1.8 and 1.2 with an area under the curve (AUC) of 0.91 and 0.84 respectively. There was a significant difference in MRS ratios between patients with neurodevelopmental delay (NDD) and patients without NDD. The cut-off values for NAA/Cr and Ch/Cr used to differentiate between patients with NDD and patients without NDD were 1.47 and 0.99, with AUC of 0.87 and 0.8 respectively. The NAA/Cr and Ch/Cr were well correlated with family history (p = 0.006 and p < 0.001) respectively, consanguinity (p < 0.001 and p = 0.001), neurodevelopmental delay (p = 0.001 and p = 0.004), serum bilirubin level (r = -0.77, p < 0.001), (r = -0.49, p = 0.014), phototherapy (p < 0.001 and p = 0.32), blood transfusion (p < 0.001 and p = 0.001) respectively. CONCLUSION: 1H-MRS can be a useful tool in the detection of neurological changes in patients with CNs-I; NAA/Cr and Ch/Cr parameters are well correlated with demographic, clinical, and laboratory findings. ADVANCES IN KNOWLEDGE: Our study is the first report on using MRS in assessing neurological manifestations in CNs. 1H-MRS can be a useful tool in the detection of neurological changes in patients with CNs-I.

Cytotoxicity and apoptosis induction of the marine Conus flavidus venom in HepG2 cancer cell line.

Cancer is still an area of continuous research for finding more effective and selective agents, so our study aimed to explore new anticancer medicines from Cone snails' venoms as marine natural products with promising biological activities. Venoms from seven cone snails collected from two locations on the Red Sea coast (Marsa Alam (Ma) and Hurghada (Hu)) were extracted and subjected to SDS for protein concentrations. The venoms of C. vexillum (Ma), C. vexillum (Hu), and C. flavidus were found to have the highest protein concentrations (2.66, 2.618, and 2.611 mg/mL, respectively). The venom of C. vexillum (Ma) was found to be cytotoxic against the lung cancer cell line A549 (IC50 = 4.511 ± 0.03 µg/mL). On the other hand, the venom of C. flavidus showed a strong cytotoxic effect on both liver and lung cancer cell lines (IC50 = 1.593 ± 0.05 and 7.836 ± 0.4 µg/mL, respectively) when compared to their normal cell lines. Investigating the apoptotic cell death of C. flavidus venom on HepG2 cell lines, it showed total apoptotic cell death by 22.42-fold compared to untreated control and arresting the cell cycle at G2/M phase. Furthermore, its apoptotic cell death in HepG2 cells was confirmed through the upregulation of pro-apoptotic markers and down-regulation of Bcl-2 in both gene and protein expression levels. These findings confirmed the cytotoxic activity of C. flavidus venom through apoptotic cell death in HepG2 cells. So, a detailed study highlighting its structure and molecular target for developing new anticancer agents from natural sources is required.Communicated by Ramaswamy H. Sarma.

Diffusion Tensor Imaging of Auditory Pathway in Patients With Crigler-Najjar Syndrome Type I: Correlation With Auditory Brainstem Response.

AIM: To evaluate the role of diffusion tensor imaging of the auditory pathway in patients with Crigler Najjar syndrome type I and its relation to auditory brainstem response. METHODS: Prospective study was done including 12 patients with Crigler Najjar syndrome type I and 10 age- and sex-matched controls that underwent diffusion tensor imaging of brain. Mean diffusivity and fractional anisotropy at 4 regions of the brain and brainstem on each side were measured and correlated with the results of auditory brainstem response for patients. RESULTS: There was significantly higher mean diffusivity of cochlear nucleus, superior olivary nucleus, inferior colliculus, and auditory cortex of patients versus controls on both sides for all regions (P = .001). The fractional anisotropy of cochlear nucleus, superior olivary nucleus, inferior colliculus, and auditory cortex of patients versus controls was significantly lower, with P values of, respectively, .001, .001, .003, and .001 on the right side and .001, .001, .003, and .001 on left side, respectively. Also, a negative correlation was found between the maximum bilirubin level and fractional anisotropy of the left superior olivary nucleus and inferior colliculus of both sides. A positive correlation was found between the mean diffusivity and auditory brainstem response wave latency of the right inferior colliculus and left cochlear nucleus. The fractional anisotropy and auditory brainstem response wave latency of the right superior olivary nucleus, left cochlear nucleus, and inferior colliculus of both sides were negatively correlated. CONCLUSION: Diffusion tensor imaging can detect microstructural changes in the auditory pathway in Crigler Najjar syndrome type I that can be correlated with auditory brainstem response.

Schindleria parva, a new species of Schindler's fish (Teleostei: Schindleriidae: Schindleria) from Jeddah, Saudi Arabia, Red Sea.

Schindleria parva, a new species of the family Schindleriidae, is described from two specimens collected from the central Red Sea of Saudi Arabia. The new species is characterized by lack of pigmentation on the body, possession of an inconspicuous gas bladder and the presence of small teeth on the premaxillae. The holotype is a female of 11 mm standard length (SL) (11.9 mm total length) and the paratype is a male of 9 mm SL. Dorsal fin rays 10 (9) anal fin rays 9 (7). The body depth at pectoral-fin origin 5% (4%) of SL, depth at anal-fin origin 8% (7%) SL, predorsal length 63% (65%) SL, preanal length 72% (72%) SL, the first anal-fin ray situated below the fourth dorsal-fin ray), a total of 23 + 16 myomeres. The female contained a series of 30 rectangular eggs in a single row, whereas the male is characterized by a short rod-like urogenital papilla. Species of the genus Schindleria are likely the smallest marine vertebrates on the planet and S. parva is likely the smallest Schindleria species in the Red Sea. The global diversity of Schindleria is likely underestimated due to the paedomorphic features of this genus. Its fast generation times make it a species-rich genus of high turnover rates, thus potentially highly important for the trophic food webs of coral reefs. Thus, this finding advances knowledge on the biodiversity of the Red Sea, highlights its conservation significance, and contributes towards the understanding of the complexity of the coral-reef fish community.

Diffusion Tensor Imaging of Microstructural Changes in the Gray and White Matter in Patients With Crigler-Najjar Syndrome Type I.

PURPOSE: This study aimed to evaluate the role of diffusion tensor imaging of microstructural changes in gray and white matter in Crigler-Najjar syndrome type I. PATIENT AND METHODS: A prospective study was conducted on 10 patients with Crigler-Najjar syndrome type I and 10 age- and sex-matched children who underwent diffusion tensor imaging of the brain. Mean diffusivity (MD) and fractional anisotropy (FA) of gray and white matter were measured. RESULTS: There was a significantly higher MD of the gray matter regions including the globus pallidus, thalamus, caudate head, substantia nigra, and dentate nucleus in patients versus controls (P = 0.007, 0.001, 0.014, 0.003, and 0.002), respectively. The areas under the curve (AUC) of MD of the globus pallidus and thalamus used to differentiate patients from controls were 0.93 and 0.925, respectively. There was a significant difference in MD of the frontal white matter and posterior limb of the internal capsule in patients versus controls (P = 0.001 and 0.02), respectively. The AUCs of MD of these regions used to differentiate patients from controls were 0.82 and 0.8. There was a significant difference in FA of the frontal white matter and posterior limb of the internal capsule in patients versus controls (P = 0.006 and 0.006), respectively. The AUCs of FA of these regions were 0.83 and 0.85, respectively. The MD of the globus pallidus correlated with serum bilirubin (r = 0.87 and P = 0.001). CONCLUSION: Diffusion tensor imaging can detect microstructural changes of deep gray matter and some regions of white matter in Crigler-Najjar syndrome type I.

Traumatic pseudoaneurysm of the brachiocephalic artery obstructing the airways.

This is a case report of a young patient referred to our ER as a case of mediastinal tumor compressing the airways. On presentation, the patient had severe stridor and tachypnea, with oxygen saturation less than 60%. As the patient presented alone to the ER, obtaining any history was not possible. Chest x-ray showed a huge right paratracheal mediastinal mass compressing the airway. The patient was not able to lie supine and was taken to the OR for intubation under fiberoptic bronchoscopy guidance. Bronchoscopic evaluation showed significant compression of the trachea from the right side. A small endotracheal tube (size 5) was successfully inserted. Then, the patient was taken for a chest CT with IV contrast. Chest CT showed a huge vascular mass compressing the trachea, the right mainstem bronchus, and the superior vena cava. The study showed the proximal innominate artery, followed by a pseudoaneurysm. There was an interruption of the right subclavian artery at its origin. Collaterals were seen supplying the right upper limb. Surgical resection was done. Postoperatively the patient gave a history of chest-penetrating injury in the right infraclavicular area, 15 years prior to presentation. The pseudoaneurysm of the innominate artery is a rare delayed complication of chest trauma.

Mediastinal ectopic thyroid mass with normal thyroid function and location: Case report.

INTRODUCTION: Mediastinal Ectopic Thyroid Gland is a rare entity, accounting for 1% of all mediastinal tumours. Here, we present a rare case of mediastinal mass that was proved to be an ectopic thyroid with normal thyroid function tests and normal thyroid gland in the cervical location. CASE PRESENTATION: A 32-year-old lady had a road traffic accident, with the incidental discovery of a mediastinal mass on chest radiography. Thyroid function tests were normal. CT scans of the neck and chest revealed a large mediastinal mass compressing the trachea from the left side and extending to the superior part of the anterior mediastinum with normal thyroid gland in the cervical position. Midline Partial Sternotomy was done with complete surgical excision of the mass. It was well circumscribed, multinodular, had firm inconsistency, and grossly looked like a thyroid tissue. Histopathology revealed ectopic thyroid tissue negative for malignancy. Postoperative thyroid ultrasound showed normal thyroid lobes in the neck. DISCUSSION: Ectopic thyroid tissue (ETT) occurs due to failure of the thyroid gland to migrate from foramen ceacum to its normal position in the cervical region in front of the trachea. The most common site of ETT is lingual thyroid and accounts for about 90% of all cases reported in the literature. ETT in the mediastinum is very rare, with only a few cases reported in the literature. CONCLUSION: ETT in the mediastinum is very rare and can be associated with normal thyroid function and normal thyroid anatomical location. It should be differentiated from substernal goiter.

Metals in a northern Nile Delta lake: water, suspended particulates, sediments, and biota.

Lake Edku is one of the important fishing areas in the Nile Delta. It is exposed to different quantities of serious pollutants in particular metals. To overall appraise the risk and status of metals in the lake, a comprehensive study of total concentrations of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), and zinc (Zn) in sediments and spatial-temporal variations of these metals in the dissolved and suspended particulates, and some tissues of Tilapias niloticus, was conducted from ten sampling sites during 2016. Results showed that none of the investigated metals exceeded the limits considered as hazardous for aquatic life in water. The highest concentrations of Cd, Cu, Ni, and Zn were observed in suspended particulate matter, which may precipitate on the surface of the sediments. Potential ecological risk analysis of the majority of the investigated metals in the sediment indicated that Lake Edku posed a low ecological risk. The estimated values of all metals in tissues of Tilapia niloticus were below the international permissible limits. Moreover, the potential risk of metals to human via the consumption of Tilapia niloticus was estimated using the weekly intake levels, which was lower than the WHO's safe provisional tolerant weekly intake levels. These results prove the importance of performing measurements of contaminants in various compartments of Lake Ecosystem including sediment, biota, and suspended particulate matter for proper management.

Target-Controlled Infusion of Remifentanil Without Muscle Relaxants Allows Acceptable Surgical Conditions During Thoracotomy Performed Under Sevoflurane Anesthesia.

OBJECTIVES: To test the hypothesis that the use of a nonmuscle relaxant anesthetic technique (NMRT) during thoracotomy would be associated with comparable surgical conditions with the standard use of neuromuscular blocking drugs. DESIGN: A prospective, randomized, single-blind, controlled study. SETTING: A single university hospital. PARTICIPANTS: Sixty-six patients scheduled for open thoracotomy under sevoflurane anesthesia with a target-controlled infusion (TCI) of remifentanil. INTERVENTIONS: After ethical approval, patients were randomly assigned to receive cisatracurium or saline (n = 33 for each group) during the entire study period. MEASUREMENTS AND MAIN RESULTS: The four-point ordinal surgical rating scale, the intubating conditions, the use of anesthetics and vasopressors, the incidence of light anesthesia (defined as an episode with state entropy values that exceeded 50 and/or mean arterial blood pressure and heart rate values that exceeded the baseline by 20% and lasted for more than 3 consecutive minutes), and the times to clinical recovery and postanesthesia care unit (PACU) discharge, hospital stays, and postoperative residual curarization (PORC) were recorded. Compared with the use of cisatracurium, the use of NMRT resulted in comparable good-to-excellent surgical rating scales (90.9% v 94.0%, respectively; p = 0.642), good-to-excellent laryngoscopy and endobronchial intubating conditions (93.9% v 100%, respectively; p>0.09), use of anesthetic and vasopressor medications, and hospital stays, together with shorter clinical recovery, extubation times (7.6 [95% CI 6.82 to 8.39] v 19.0 [95% CI 15.76 to 22.23] minutes, respectively; p<0.001), and PACU stays (37.4 [95% CI 35.09 to 39.79] v 70.9 [95% CI 56.90 to 84.91] minutes, respectively; p<0.001). The use of cisatracurium resulted in a nonstatistical number of light anesthesia episodes upon positioning, skin incision, and rib separation (p>0.624, with Fisher's exact test). There were no failed intubations in the 2 groups. No patient received cisatracurium in the NMRT group. Two patients (6.1%) in the cisatracurium group experienced PORC that required tracheal intubation in the PACU. CONCLUSION: The use of TCI of remifentanil with NMRT offers acceptable laryngoscopy, intubating, and surgical conditions during sevoflurane anesthesia for open thoracotomy, especially when. the anesthesiologists have more than 10 years' experience.

Primary Pulmonary Hodgkin Lymphoma.

Primary pulmonary Hodgkin lymphoma (PPHL) is a rare disease. Herein, we report a case of PPHL with diagnostic concerns encountered during initial evaluation which is of paramount importance to keep the differential diagnosis in cases with high index of suspicion for this rare entity.

Effect of tidal volume on extravascular lung water content during one-lung ventilation for video-assisted thoracoscopic surgery: a randomised, controlled trial.

BACKGROUND: The use of low tidal volume during one-lung ventilation (OLV) has been shown to attenuate the incidence of acute lung injury after thoracic surgery. OBJECTIVE: To test the effect of tidal volume during OLV for video-assisted thoracoscopic surgery on the extravascular lung water content index (EVLWI). DESIGN: A randomised, double-blind, controlled study. SETTING: Single university hospital. PARTICIPANTS: Thirty-nine patients scheduled for elective video-assisted thoracoscopic surgery. INTERVENTIONS: Patients were randomly assigned to one of three groups (n = 13 per group) to ventilate the dependent lung with a tidal volume of 4, 6 or 8 ml  kg(-1) predicted body weight with I:E ratio of 1:2.5 and PEEP of 5 cm H2O. MAIN OUTCOME MEASURES: The primary outcomes were perioperative changes in EVLWI and EVLWI to intrathoracic blood volume index (ITBVI) ratio. Secondary outcomes included haemodynamics, oxygenation indices, incidences of postoperative acute lung injury, atelectasis, pneumonia, morbidity and 30-day mortality. RESULTS: A tidal volume of 4 compared with 6 and 8 ml  kg(-1) after 45 min of OLV resulted in an EVLWI of 4.1 [95% confidence interval (CI) 3.5 to 4.7] compared with 7.7 (95% CI 6.7 to 8.6) and 8.6 (95% CI 7.5 to 9.7) ml  kg(-1), respectively (P < 0.003). EVLWI/ITBVI ratios were 0.57 (95% CI 0.46 to 0.68) compared with 0.90 (95% CI 0.75 to 1.05) and 1.00 (95% CI 0.80 to 1.21), respectively (P < 0.05). The incidences of postoperative acute lung injury, atelectasis, pneumonia, morbidity, hospitalisation and 30-day mortality were similar in the three groups. CONCLUSION: The use of a tidal volume of 4 ml kg during OLV was associated with less lung water content than with larger tidal volumes of 6 to 8 ml kg(-1), although no patient developed acute lung injury. Further studies are required to address the usefulness of EVLWI as a marker for the development of postoperative acute lung injury after the use of a low tidal volume during OLV in patients undergoing pulmonary resection. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01762709.

Right ventricular function during one-lung ventilation: effects of pressure-controlled and volume-controlled ventilation.

OBJECTIVES: To test the effects of pressure-controlled (PCV) and volume-controlled (VCV) ventilation during one-lung ventilation (OLV) for thoracic surgery on right ventricular (RV) function. DESIGN: A prospective, randomized, double-blind, controlled, crossover study. SETTING: A single university hospital. PARTICIPANTS: Fourteen pairs of consecutive patients scheduled for elective thoracotomy. INTERVENTIONS: Patients were assigned randomly to ventilate the dependent lung with PCV or VCV mode, each in a randomized crossover order using tidal volume of 6 mL/kg, I: E ratio 1: 2.5, positive end-expiratory pressure (PEEP) of 5 cm H2O and respiratory rate adjusted to maintain normocapnia. MEASUREMENTS AND MAIN RESULTS: Intraoperative changes in RV function (systolic and early diastolic tricuspid annular velocity (TAV), end-systolic volume (ESV), end-diastolic volume (EDV) and fractional area changes (FAC)), airway pressures, compliance and oxygenation index were recorded. The use of PCV during OLV resulted in faster systolic (10.1±2.39 vs. 5.8±1.67 cm/s, respectively), diastolic TAV (9.2±1.99 vs. 4.6±1.42 cm/s, respectively) (p<0.001) and compliance and lower ESV, EDV and airway pressures (p<0.05) than during the use of VCV. Oxygenation indices were similar during the use of VCV and PCV. CONCLUSIONS: The use of PCV offers more improved RV function than the use of VCV during OLV for open thoracotomy. These results apply specifically to younger patients with good ventricular and pulmonary functions.

Changes in cerebral oxygenation in patients with pulmonary dysfunction after lung resection.

Lung resection would be associated with lower jugular bulb oxygen saturation (SjvO2) values in patients with moderate to severe pulmonary dysfunction. We aimed to study the effects of lung resections on the postoperative changes in SjvO2, incidence of SjvO2 < 50%, pulmonary functions, cerebral blood flow equivalent (CBFE), and arterial to jugular difference in oxygen content (AjvDO2) in the patients with pulmonary dysfunction. Fifty-three patients scheduled for lung resection were allocated on the basis of forced vital capacity (FVC %) and forced expiratory volume in 1 second (FEV(1)%) into the following: good FVC and FEV1 (n = 14), mild (n = 14), moderate (n = 13), and severe (n = 12) pulmonary dysfunction groups. After lung resections, patients with pulmonary dysfunctions had significantly lower SjvO2, CBFE, FEV1, and FVC (P < .001), higher AjvDO2 (P < .001), and frequent episodes with SjvO2 < 50% (P < .03). Perioperative changes in FEV1 had a significant negative correlation with SjvO2 desaturation (P < .002). Patients with pulmonary dysfunction showed significant SjvO2 < 50% after lung resection, which is correlated to the perioperative changes in FEV1.

Comparative study of the non-dependent continuous positive pressure ventilation and high-frequency positive-pressure ventilation during one-lung ventilation for video-assisted thoracoscopic surgery.

The application of volume controlled high-frequency positive-pressure ventilation (HFPPV) to the non-dependent lung (NL) may have comparable effects to continuous positive-airway pressure (CPAP) on the surgical conditions during one-lung ventilation (OLV) for video-assisted thoracoscopic surgery (VATS). After local Ethics Committee approval and informed consent, we randomly allocated 30 patients scheduled for elective VATS after the first 15 min of OLV to ventilate the NL with CPAP of 2 cm H(2)O (NL-CPAP(2)) and HFPPV using tidal volume 2 ml/kg, inspiratory to expiratory ratio <0.3 and respiratory rate 60/min (NL-HFPPV) for 30 min, each in a randomized crossover order. Intraoperative adequacy of surgical conditions was evaluated using a visual analog scale and the changes in hemodynamic and arterial oxygen were recorded. The application of NL-CPAP(2) and NL-HFPPV resulted in more improved arterial oxygenation than during OLV for VATS (P<0.001). The operative field was much better during the application of NL-CPAP(2) than during NL-HFPPV (P<0.001). We concluded that the application of CPAP to the NL during OLV offers good quality of operative field and improved arterial oxygenation for VATS.

Primary mediastinal Castleman's disease.

Castleman's disease is a rare entity with an unknown etiology which was first described by Castleman in 1954. It is a lymphoproliferative disorder histologically classified into three types; hyaline-vascular, plasma cell type and mixed type. It might be localized or multicentric and usually involves the mediastinum. We report a case of Castleman's disease discovered accidentally in a case of blunt chest trauma which caused a challenging diagnostic process and management.

Effects of nondependent lung ventilation with continuous positive-pressure ventilation and high-frequency positive-pressure ventilation on right-ventricular function during 1-lung ventilation.

Background. The application of volume-controlled high frequency positive pressure ventilation (HFPPV) to the nondependent lung (NL) may have comparable effects to continuous positive airway pressure (CPAP) on the right ventricular (RV) function, oxygenation, and surgical conditions during one lung ventilation (OLV) for thoracotomy. Methods. After local ethics committee approval and informed consent, 75 patients scheduled for elective thoracotomy using OLV were randomly allocated to receive nondependent lung either CPAP 2 (CPAP2; n=25) or 5 (CPAP5; n=25) cm H2O pressure setting of the device or HFPPV using VT 3 mL-1, I: E ratio <0.3 and R.R 60/min (HFPPV; n=25), followed 15 min of OLV. Intraoperative changes in RV ejection fraction (REF), end-diastolic volume (RVEDVI) and stroke work (RVSWI), stroke volume (SVI), oxygen delivery (DO2), and uptake (VO2) indices and shunt fraction (Qs: Qt) were recorded without any surgical manipulation of the lung. Results. The application of NL-HFPPV resulted in improved REF by 33%, SVI and DO2 (P < 0.01) and reduced RVEDVI, RVSWI, PVRI, oxygen uptake, and shunt fraction by 24.8% (P < 0.01) than in the NL-CPAP groups. Conclusion. We concluded that the use of NL-HFPPV is a feasible option and offers improved RV function and oxygenation during OLV for open thoracotomy.

Is Routine Spiral CT-Chest Justified in Evaluation of the Major Blunt Trauma Patients?

STUDY: New generation spiral CT scanners permit multiple consecutive CT examinations on the same trauma patient in a short period of time. The purpose of this study was to evaluate the diagnostic role and therapeutic impact of routine spiral CT chest in multiply injured patients or patients with a suspicious mechanism of injury. PATIENTS AND METHODS: This prospective study included 443 patients with blunt chest trauma. All patients underwent a spiral CT chest as part of their routine evaluation. Radiological interpretation of chest x-rays, CT scan findings, and changes in management plan guided by these findings were recorded. RESULTS: The mechanism of injury was road traffic accidents in 422 patients (95.26%). Out of the 167 patients with normal chest radiograph, 136 (81.43%) were found to have an abnormality on chest CT. The management was changed in the form of additional investigations or unplanned intervention in 92 patients (20.76%). Additional investigations included transoesophageal echocardiography (n = 7), bronchoscopy (n = 13), transfer to higher center for aortography (n = 2). Intercostal tubes (n = 55), thoracotomies (n = 4), fixation of sternal fracture (n = 9), laparotomy (n = 1) and spinalfixation (n = 1) were performed following the CT scan. CONCLUSION: Although the incidence of significant injuries identified by the chest CT scan was low, it did prompt immediate intervention in a significant number of patients; some of them had potentially life-threatening injuries. Routine use of CT scanning is warranted in early evaluation of polytrauma patients or patients with severe blunt chest trauma.