Cognitive, language and social-cognitive skills of individuals with fragile X syndrome with and without autism

Background It is not known whether those with co‐morbid fragile X syndrome (FXS) and autism represent a distinct subtype of FXS; whether the especially severe cognitive delays seen in studies of young children with co‐morbid FXS and autism compared with those with only FXS continue into adolescence and young adulthood; and whether autism in those with FXS is ‘true autism’, i.e. reflects the same underlying problems as idiopathic autism. Method We compared the non‐verbal IQ of adolescents and young adults with co‐morbid FXS and autism (n = 10) with those with only FXS (n = 44). We then created a subsample of those with FXS only, matched on non‐verbal IQ, mental age and gender (n = 21) to the subsample of those with co‐morbid FXS and autism. We compared the two groups on measures of expressive language, receptive language (lexical, grammatical morphology and syntactic patterns), and a theory of mind task. Results Those with co‐morbid FXS and autism had lower non‐verbal IQs than those with only FXS. The participants with co‐morbid FXS and autism did not perform as well as the cognitive ability‐ and gender‐matched participants with only FXS on the three measures of receptive language or the theory of mind task; there were no differences on the expressive language measure. Conclusions Our findings support the notion that those with co‐morbid FXS and autism represent a distinct subtype of FXS, with more impairment in receptive language and theory of mind even when controlling for their lower non‐verbal IQ relative to those with only FXS. The greater cognitive impairments observed in those with co‐morbid FXS and autism continues into adolescence and young adulthood; and the autism seen in those with FXS appears to be the same as idiopathic autism.     

Primary tumor dependent inhibition of tumor growth,angiogenesis, and perfusion of secondary breast cancer in bone

The systemic balance of angiogenic and anti‐angiogenic factors has been proposed to play a key‐role in primary tumor growth dependent growth suppression of secondary tumors. Despite the importance of the organ microenvironment to angiogenesis and microcirculation, the influence of a primary tumor on secondary bone tumors has not been investigated so far. Since breast cancer has a high propensity to spread to bone, we used an in vivo xenograft model to determine the impact of growing breast cancer cells (MCF‐7) in the mammary fat pad on the microvascular properties of subsequently inoculated secondary breast cancer tumors in bone. Mice were either treated with a resection of the primary tumor (n = 10) or no surgery (n = 9) and intravital microscopy was performed over 25 days in bone tumors. Tumor growth in bone was temporarily suppressed by the primary tumor on days 10 and 14. While microvascular permeability and vascular diameter decreased in both groups over time, the presence of the primary tumor was accompanied by a decreased tumor perfusion on days 8 and 10 through a reduction in vessels with diameters between 5 and 20 µm. The results imply a potential benefit of a therapeutic regime in which the resection of the primary tumor is combined with an anti‐angiogenic therapy in the perioperative or direct postoperative period. This might result in reduced progression of bone metastasis subsequent to excision of the primary tumor. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1251–1258, 2011     

Cardiorespiratory effects of automatic tube compensation during airway pressure release ventilation in patients with acute lung injury

BACKGROUND: Spontaneous breaths during airway pressure release ventilation (APRV) have to overcome the resistance of the artificial airway. Automatic tube compensation provides ventilatory assistance by increasing airway pressure during inspiration and lowering airway pressure during expiration, thereby compensating for resistance of the artificial airway. The authors studied if APRV with automatic tube compensation reduces the inspiratory effort without compromising cardiovascular function, end-expiratory lung volume, and gas exchange in patients with acute lung injury. METHODS: Fourteen patients with acute lung injury were breathing spontaneously during APRV with or without automatic tube compensation in random order. Airway pressure, esophageal and abdominal pressure, and gas flow were continuously measured, and tracheal pressure was estimated. Transdiaphragmatic pressure time product was calculated. End-expiratory lung volume was determined by nitrogen washout. The validity of the tracheal pressure calculation was investigated in seven healthy ventilated pigs. RESULTS: Automatic tube compensation during APRV increased airway pressure amplitude from 7.7+/-1.9 to 11.3+/-3.1 cm H2O (mean +/- SD; P < 0.05) while decreasing trans-diaphragmatic pressure time product from 45+/-27 to 27+/-15 cm H2O x s(-1) x min(-1) (P < 0.05), whereas tracheal pressure amplitude remained essentially unchanged (10.3+/-3.5 vs. 10.1+/-3.5 cm H2O). Minute ventilation increased from 10.4+/-1.6 to 11.4+/-1.5 l/min (P < 0.001), decreasing arterial carbon dioxide tension from 52+/-9 to 47+/-6 mmHg (P < 0.05) without affecting arterial blood oxygenation or cardiovascular function. End-expiratory lung volume increased from 2,806+/-991 to 3,009+/-994 ml (P < 0.05). Analysis of tracheal pressure-time curves indicated nonideal regulation of the dynamic pressure support during automatic tube compensation as provided by a standard ventilator. CONCLUSION: In the studied patients with acute lung injury, automatic tube compensation markedly unloaded the inspiratory muscles and increased alveolar ventilation without compromising cardiorespiratory function and end-expiratory lung volume.     

Screening for aortoiliac lesions by visual interpretation of the common femoral Doppler waveform.

OBJECTIVE: to study the accuracy of simple visual interpretation of the common femoral artery Doppler waveform for screening the aorto-iliac segment for significant occlusive disease. DESIGN: prospective and semi-blinded study. Material ninety-four consecutive and elective patients having arteriography due to chronic lower limb ischaemia, presenting symptoms of severe claudication (23%), ischaemic rest pain (34%) or ischaemic skin lesions (43%). METHODS: one day prior to conventional arteriography a Doppler waveform was obtained in the common femoral artery. Based on visual interpretation, the waveforms were immediately categorised as normal or abnormal. Comparison with single plane arteriography with respect to significant aorto-iliac occlusive disease was undertaken. RESULTS: visual Doppler waveform interpretation had a sensitivity of 98% (95% CI: 90-100%), a specificity of 81% (CI: 67-90%), a positive predictive value of 86% (CI: 75-93%) and a negative predictive value of 97% (CI: 86-100%) for prediction of significant aorto-iliac occlusive disease using conventional arteriography as the gold standard. The kappa value for the agreement between Doppler waveform interpretation and arteriography was 0.81 (0.68-0.93), representing very good agreement. CONCLUSION: a normal common femoral Doppler waveform can safely exclude significant upstream aorto-iliac lesions and is a useful timesaving screening tool in the busy vascular laboratory. The method is well tolerated, easy to perform and requires no additional equipment.     

Modeling of the naked facet sign in the thoracolumbar spine

On transverse computed tomographic (CT) scan cuts of the thoracolumbar spine, the naked facet sign occurs when the inferior articular facets of the cephalad vertebra do not appear adjacent to the superior facets of the subjacent caudal vertebra. The objective of this study was to determine the angles of rotation required for the naked facet sign to occur in the thoracolumbar spine, with the center of rotation located at various points in or anterior to the vertebral body. A commercial spinal model and visualization software were used to simulate various flexion injuries. Each functional spinal unit (FSU; T11-T12, T12-L1, and L1-L2) was examined separately. In the model, two CT scan slices (each 2 mm thick) were created parallel to the inferior end plate of the cephalad vertebra of each FSU. The cephalad vertebra was rotated in 0.5 degrees increments, and after rotation both modeled CT slices were examined for the presence of the naked facet sign. If the sign did not occur, the process was repeated, rotating the cephalad vertebra an additional 0.5 degrees until the naked facet sign occurred. The angle of rotation necessary for the sign to occur increases as the point of rotation of the vertebra moves from anterior to posterior and from superior to inferior. The naked facet sign occurred at a minimum rotation angle of 5 degrees (with respect to the anterior-superior point on T11) and at a maximum rotation angle of 16.5 degrees (with respect to the posterior-inferior point on L1). For rotations about a point located 3 cm anterior to the vertebral body, the minimum angles required for the sign decreased only 1 degrees for each FSU. These results suggest that the naked facet sign does not consistently imply the presence of posterior column vertebral instability. This will help clinicians to relate the mechanism of injury, radiographic findings (including the naked facet sign), and the implied injury pattern to the determination of stability, and ultimately the management options for the injury.     

Risk factors for laryngospasm in children during general anesthesia

Background:  Laryngospasm is a common and often serious adverse respiratory event encountered during anesthetic care of children. We examined, in a case control design, the risk factors for laryngospasm in children.
Material and Methods:  The records of 130 children identified as having experienced laryngospasm under general anesthesia were examined. Cases were identified from those prospectively entered into the Mayo Clinic performance improvement database between January 1, 1996 and December 31, 2005. Potential demographic, patient, surgical and anesthetic related risk factors were determined in a 1 : 2 case–control study.
Results:  No individual demographic factors were found to be significantly associated with risk for laryngospasm. However, multivariate analysis demonstrated significant associations between laryngospasm and intercurrent upper respiratory infection (OR 2.03 P  =   0.022) and the presence of an airway anomaly (OR   =   3.35, P  =   0.030). Among those experiencing laryngospasm during maintenance or emergence, the use of a laryngeal mask airway was strongly associated even when adjusted for the presence of upper respiratory infection and airway anomaly ( P  =   0.019). Ten patients experienced postoperatively one or more complications whereas only three complications were observed among controls ( P  =   0.008). No child required cardiopulmonary resuscitation and there were no deaths in either study cohort.
Conclusions:  In our pediatric population, the risk of laryngospasm was increased in children with upper respiratory tract infection or an airway anomaly. The use of laryngeal mask airway was found to be associated with laryngospasm even when adjusted for the presence of upper respiratory tract infection and airway anomaly.     

Perioperative cardiac arrests in children between 1988 and 2005 at a tertiary referral center: a study of 92,881 patients

BACKGROUND: The objective of this study was to determine the incidence and outcome of perioperative cardiac arrest (CA) in children younger than 18 yr undergoing anesthesia for noncardiac and cardiac procedures at a tertiary care center. METHODS: After institutional review board approval (Mayo Clinic, Rochester, Minnesota), all patients younger than 18 yr who had perioperative CA between November 1, 1988, and June 30, 2005, were identified. Perioperative CA was defined as a need for cardiopulmonary resuscitation or death during anesthesia care. A cardiac procedure was defined as a surgical procedure involving the heart or great vessels requiring an incision. RESULTS: A total of 92,881 anesthetics were administered during the study period, of which 4,242 (5%) were for the repair of congenital heart malformations. The incidence of perioperative CA during noncardiac procedures was 2.9 per 10,000, and the incidence during cardiac procedures was 127 per 10,000. The incidence of perioperative CA attributable to anesthesia was 0.65 per 10,000 anesthetics, representing 7.5% of the 80 perioperative CAs. Both CA incidence and mortality were highest among neonates (0-30 days of life) undergoing cardiac procedures (incidence: 435 per 10,000; mortality: 389 per 10,000). Regardless of procedure type, most patients who experienced perioperative CA (88%) had congenital heart disease. CONCLUSION: The majority of perioperative CAs were caused by factors not attributed to anesthesia, in distinction to some recent reports. The incidence of perioperative CA is many-fold higher in children undergoing cardiac procedures, suggesting that definition of case mix is necessary to accurately interpret epidemiologic studies of perioperative CA in children.     

Intrathecal anesthesia and recovery from radical prostatectomy: a prospective, randomized, controlled trial

BACKGROUND: Previous studies suggest that intraoperative anesthetic care may influence postoperative pain and recovery from surgery. The authors tested the hypothesis that the addition of intrathecal analgesia to general anesthesia would improve long-term functional status and decrease pain in patients undergoing radical retropubic prostatectomy. METHODS: One hundred patients received either general anesthesia supplemented with intravenous fentanyl or general anesthesia preceded by intrathecal administration of bupivacaine (15 mg), clonidine (75 microg), and morphine (0.2 mg). Patients and providers were masked to treatment assignment. All patients received multimodal pain management postoperatively. Primary outcomes included pain and functional status over the first 12 postoperative weeks. RESULTS: Patients receiving intrathecal analgesia required more intravenous fluids and vasopressors intraoperatively. Pain was well controlled throughout the study (mean numerical pain scores < 3 in both groups at all times studied). Intrathecal analgesia decreased pain and supplemental intravenous morphine use over the first postoperative day but increased the frequency of pruritus. Pain and functional status after discharge from the hospital did not differ between groups. Intrathecal analgesia significantly decreased the duration of hospital stay (from 2.8 +/- 2.0 to 2.1 +/- 0.5 days; P < 0.01) as a result of five patients in the control group who stayed in the hospital more than 3 days. CONCLUSIONS: The benefits of improved immediate analgesia and decreased morphine requirements resulting from intrathecal analgesia must be weighed against factors such as pruritus, increased intraoperative requirement for fluids and vasopressors, and resources needed to implement this modality. Further studies are needed to determine the significance of the decrease in duration of hospital stay.