Vascular compression of the airway: Indications for and results of surgical management

Vascular compression of the airway is a significant cause of respiratory compromise in children. While the indications for surgical repair are sometimes life threatening, they can also be subtle. This retrospective study examines 45 surgical cases of tracheobronchial compromise secondary to vascular compression at a large children's hospital between July 1983 and February 1996. A total of 34 were diagnosed with innominate artery compression, ten with a double aortic arch and one with an anomalous right subclavian artery. The 45 patients, 25 male and 20 female, ranged in age from 12 days to 11 years at surgery (average 13 months). A total of 21 (47%) presented with proven or suspected episodes of cyanosis or apnea. All 45 patients had evidence of vascular compression during microlaryngoscopy and bronchoscopy. The diagnosis was confirmed by magnetic resonance imaging (MRI) in 23/45 (51%), barium swallow in 22/45 (49%) and aortogram in 3/45 (7%). There was one death. One patient had a tracheotomy before surgery and continues to require it after surgery. Complete resolution of symptoms was achieved in 39/45 (87%) with five requiring more than one operation before their symptoms resolved completely. A total of four patients experienced a recurrence of symptoms within a variable length of time after surgery. Surgical indications and treatment alternatives will be discussed.     

The Relationship of Ambulation in Labor to Operative Delivery

An abbreviated version of the Nurse-Midwifery Clinical Data Set was used to gather data on all women (n = 3,049) who began intrapartum care with a nurse-midwife in three sites. Demographic information, intrapartum care, and outcomes were recorded. The association of ambulation in labor with operative delivery was examined in a low-risk sample (n = 1,678) of women who did not receive care measures (epidural anesthesia, oxytocin induction or augmentation) that preclude mobility in labor. Women who ambulated for a significant amount of time during labor (compared with those who did not ambulate) had half the rate of operative delivery (2.7% vs. 5.5%).     

INFORMED CONSENT FOR EPIDURAL ANALGESIA IN LABOR

Epidural analgesia is widely available and increasingly popular in the United States for pain relief in childbirth. Although it provides superior pain relief for most women, it is not without significant short- and long-term side effects. It is costly and requires the use of numerous other technologic interventions. Because women have information needs surrounding childbirth and value self-determination, full informed consent regarding epidural analgesia should be a priority in patient care. The best time and place in which to accomplish this is during the prenatal period.     

Raised saturated-fat intake worsens vascular function in virgin and pregnant offspring of streptozotocin-diabetic rats

Adult offspring of severely diabetic pregnant rats are insulin resistant and display cardiovascular dysfunction. When pregnant they develop mild hyperglycaemia. Diets high in saturated fat have been implicated in the development of cardiovascular disease and vascular dysfunction. In the present study we have determined vascular function in small mesenteric arteries from offspring of normal (OC) and diabetic (OD) rats fed standard chow and offspring of diabetic rats fed a diet high in saturated fats (OD-HF) from weaning to adulthood, and throughout their subsequent pregnancies. OD rats displayed an increased sensitivity to noradrenaline (P < 0.05) and impaired sensitivity to the endothelium-dependent vasodilator, acetylcholine. The component of acetylcholine-induced relaxation attributable to endothelium-derived hyperpolarizing factor was reduced in OD-HF rats. Pregnant OD rats also demonstrated impaired maximum relaxation to acetylcholine (pregnant OD rats v. pregnant OC rats P < 0.05). In pregnant OD-HF rats noradrenaline sensitivity was enhanced and endothelium-dependent relaxation further reduced (pregnant OD-HF rats v. pregnant OC rats P < 0.001). The isoprostane, 8-epi-prostaglandin F2alpha, a marker of oxidative stress, was increased in pregnant OD rats (pregnant OD rats v. pregnant OC rats P     

Anxiogenic effects of Sumatriptan in panic disorder: a double-blind, placebo-controlled study.

BACKGROUND: Several lines of evidence point to serotonergic abnormalities in patients with panic disorder (PD). Our goal was to further examine central serotonergic function in panic patients using autonomic and subjective responses to the postsynaptic serotonin 5-HT1D receptor agonist Sumatriptan. METHOD: Using a double-blind, randomized, placebo-controlled design, we assessed autonomic and subjective responses to oral Sumatriptan (100 mg) and placebo in 15 patients with PD, free of medication. Subjective responses were measured using the Hamilton Anxiety Rating Scale (HAM-A), National Institute of Mental Health Anxiety Scale (NIMHA), a modified version of the Panic Symptom Inventory (PI), Hamilton Depression Rating Scale (HAM-D), and Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: PD patients exhibited significantly enhanced autonomic and subjective responses following challenge with Sumatriptan. We observed an increased pulse rate and augmentation of various parameters measured on different anxiety scales. A constant inclination of aggravation of the measured parameters was detected during the hour post challenge. CONCLUSION: Oral administration of Sumatriptan, a 5-HT1D agonist, has been associated with an anxiogenic effect in PD patients.     

Comparison of a new video-optical intubation stylet versus the conventional malleable stylet in simulated difficult tracheal intubation

Handling and efficacy of a new video-optical intubation stylet were assessed in a simulated difficult tracheal intubation setting and compared with a conventional malleable stylet. Forty-five anaesthetists performed 10 tracheal intubations using both techniques. Laryngoscopy was performed by the observer, who created a grade 3 view according the classification by Cormack and Lehane. The time taken to place the tracheal tube and the final tracheal tube positions were documented. Mean (SD) intubation time for the video-optical stylet was 20.4 (7.7) s and for the malleable stylet 10.2 (3.3) s (p<0.01). With the video-optical stylet the trachea was correctly intubated in all 225 attempts; with the malleable stylet 44 (19.6%) oesophageal and 44 (19.6%) endobronchial intubations occurred (p<0.01). The video-optical intubation stylet enabled us to recognise inappropriate tracheal tube positions and to correct them immediately. This equipment can be considered a reliable and effective tool for management of the difficult airway.     

Tropisetron zur Prophylaxe von postoperativem Erbrechen bei Kindern

BACKGROUND: Postoperative nausea and vomiting (PONV) after tonsillectomy is a common problem in children. Tropisetron is a new 5HT3 receptor antagonist and is successfully used in paediatric patients receiving cancer therapy. The aim of the study was to assess efficacy and safety of a single intravenous dose of tropisetron for prevention of PONV in paediatric patients at risk for postoperative vomiting. METHODS: In a randomised, double-blind, placebo-controlled trial, we studied 98 children aged 2-12 years undergoing tonsillectomy or adenotonsillectomy. Patients received placebo or tropisetron 0.1 mg (= 0.1 ml)/kg body weight immediately after induction of anesthesia. A standard general anesthetic technique (Sevoflurane/N2O/O2 without neuromuscular blockers or opioids) was used. Perioperative vital signs, grade of sedation and episodes of postoperative nausea and vomiting were recorded. RESULTS: No vomiting episodes occurred in 65.3% of the tropisetron treated patients compared to 34.7% of the placebo group (p = 0.0024). Only 10.2% of the tropisetron treated patients vomited more than 3 times compared to 22.4% of the control patients (p = 0.0004). The need for antiemetic rescue medication was significantly lower in the study group (10.4%) compared to 28.6% (p = 0.025). No significant adverse effects of the study medication were shown. CONCLUSION: A single intravenous prophylactic dose of tropisetron effectively reduces the incidence of PONV during the first 24 postoperative hours after tonsillectomy and/or adenoidectomy. Because of the low incidence of adverse effects, the prophylactic use of tropisetron seems to be safe and justified in paediatric surgical patients at high risk for postoperative vomiting.     

In vitro effects of different medium molecular hydroxyethyl starch solutions and lactated Ringer's solution on coagulation using SONOCLOT

Hydroxyethyl starch (HES) solutions are widely used to replace intravascular volume. HES solutions differ from each other with regard to molecular weight and mode of hydroxyl substitution (degree of hydroxylation, C2:C6 hydroxyethyl ratio, concentration), factors which may have varying effects on coagulation. We studied, in vitro, three different HES preparations (molecular weight/degree of hydroxylation/concentration/C2:C6 ratio of substitution 70.000/0. 5/6%/3.2; Pharmacia & Upjohn Co., Erlangen, Germany; 130.000/0. 4/6%/11.2 and 200.000/0.5/6%/4.6; Fresenius Co., Bad Homburg, Germany) and, for comparison, lactated Ringer's solution (RL) at 33% and 66% dilution with whole blood. The influence of hemodilution was measured by using routine laboratory variables and SONOCLOT (Sonoclot II Coagulation and Platelet Function Analyzer, Sienco Co.) analysis, using a viscoelastic test, on the cellular as well as on the plasmatic hemostatic system. For statistical analysis of quantitative data, we used nonparametric analysis of variance and adequate post hoc tests. Qualitative data were analyzed by using the nonparametric Kruskal-Wallis test. A P value below 0.05 was considered significant. In contrast to the control group with RL, the liquid phase of coagulation (activated clotting time) was slightly affected by the 33% diluted HES solutions. HES 70.000, 130. 000, and 200.000 interfered significantly with the early stage of coagulation as expressed by the clot rate (gel/fibrin formation). Clot maturation and speed of maturation (time to peak) were strongly affected by HES 70.000 at all grades of dilution. HES 130.000 showed a faster clot formation process compared with the other HES solutions. HES 130.000 diluted 33% showed a better clot retraction as compared with the other HES solutions. In conclusion, in vitro hemodilution comparing different medium molecular weight HES solutions reveals that HES 130.000 seems preferable regarding some aspects of clot formation and retraction. RL affected clot formation only minimally, except for the early activation of clotting, which was measured by a shortened activated clotting time. IMPLICATIONS: We investigated the effect of different hydroxyethyl starch (HES) solutions (70.000, 130.000, 200.000) on coagulation. Regarding clot formation and retraction, HES 130.000 had some advantages over the other tested HES solutions. Lactated Ringer's solution affected coagulation only minimally, except for the early stage of clot formation.     

Mutations in the tyrosine kinase domain of the epidermal growth factor receptor in non-small cell lung cancer.

We evaluated somatic genetic alterations in the kinase domain of the EGFR gene in the tumors of 219 non-small cell lung cancer patients of primarily Caucasian and African American origins. We identified 26 patients (12%) whose tumors had a mutation in the EGFR gene, and 11 (5%) patients carried novel genomic variations consistent with germ-line polymorphisms. All but one mutation were identified in Caucasian patients affected with adenocarcinoma. EGFR mutations were more frequent in women and in nonsmokers, but a significant portion of the affected patients were men (12 of 26) and current or past smokers accounted for half of the patients affected (13 of 26). Screening subjects with EGFR mutations may identify patients whose tumors could respond to targeted therapy using tyrosine kinase inhibitors.