Intraoperative Tracheal Obstruction Management among Patients with Anterior Mediastinal Masses.

BACKGROUND: Patients suffering from undiagnosed obstruction of the central airways: the trachea and main stem bronchi are at increased risk for perioperative and postoperative complications, especially if general anesthesia is performed. CASE DESCRIPTION: This report discusses a 30-year-old asymptomatic Caucasian female who faced recurrent distal airway collapse during mediastinoscopy for biopsy of an anterior mediastinal mass, which led to the inability to extubate her. This case examines the necessity of a thorough preoperative assessment especially in patients with undiagnosed tracheal obstruction and a precise coordination between anesthesiologist and surgeon in being able to perform a safe and smooth anesthesia, in order to avoid life-threatening complications and to reduce further morbidity. METHODS: The scope of this case report is restricted to publications in all surgical and anesthesiological specialties among adult patient population. Main search key words were as follows: "tracheal obstruction," "general anesthesia," "mediastinum," and "tumors" Results. The literature supports an increased perioperative risk of airway obstruction with the use of general anesthesia in patients with anterior mediastinal masses. This case report suggests a perioperative anesthetic management modality for patients presenting with anterior mediastinal masses and who are at high risk of cardiovascular compression and tracheal obstruction. Thus, it is highly important to note that evidence-based recommendations are not available in the literature. CONCLUSIONS: This case report suggests perioperative management modalities performed by anesthesiologists in order to minimize the risk of airway obstruction among patients having anterior mediastinal masses and shed the lights on the importance of proper anesthetic and surgical planning in order to prevent intraoperative complications and improve the quality of healthcare provided to patients presenting critical cases.

[Intensity modulation in breast radiotherapy: development of an innovative field-in-field technique at Institut Gustave-Roussy]. / Modulation d'intensité en radiothérapie mammaire : développement d'une méthode innovante de champ dans le champ à l'institut Gustave-Roussy.

PURPOSE: To assess the potential dosimetric gain of presegmentation modulated radiotherapy (OAPS, DosiSoft™) of breast, compared to routine 3D conformal radiotherapy. PATIENTS AND METHODS: Twenty patients treated with conservative surgery for breast cancer (9 right and 11 left sided) with various breast volume (median 537 cm(3); range [100-1049 cm(3)]) have been selected. For each patient, we have delineated a breast volume and a compensation volume (target volumes), as well as organs at risk (lungs and heart). Two treatment plans have been generated: one using the routine 3D conformal technique and the other with the presegmentation algorithm of DosiSoft™ (OAPS). The dose distribution were analyzed using the conformity index for target volumes, mean dose and V30 Gy for the heart, and mean dose, V20 Gy and V30 Gy for lungs. RESULTS: Over the 20 patients, the conformity index increased from 0.897 with routine technique to 0.978 with OAPS (P<0,0001). For heart and lung, OAPS decreased irradiation (mean cardiac dose 1,3 vs 1,6 Gy [P<0,0001] and pulmonary V20 Gy 6,6 vs 7,1 [P<0,0001]). CONCLUSION: OAPS (DosiSoft™) is an original method of segmentation of breast. It is automatic, fast and easy, and is able to increase the conformity index, while sparing organ at risk.

Individual radiation therapy patient whole-body phantoms for peripheral dose evaluations: method and specific software.

This study presents a method aimed at creating radiotherapy (RT) patient-adjustable whole-body phantoms to permit retrospective and prospective peripheral dose evaluations for enhanced patient radioprotection. Our strategy involves virtual whole-body patient models (WBPM) in different RT treatment positions for both genders and for different age groups. It includes a software tool designed to match the anatomy of the phantoms with the anatomy of the actual patients, based on the quality of patient data available. The procedure for adjusting a WBPM to patient morphology includes typical dimensions available in basic auxological tables for the French population. Adjustment is semi-automatic. Because of the complexity of the human anatomy, skilled personnel are required to validate changes made in the phantom anatomy. This research is part of a global project aimed at proposing appropriate methods and software tools capable of reconstituting the anatomy and dose evaluations in the entire body of RT patients in an adapted treatment planning system (TPS). The graphic user interface is that of a TPS adapted to obtain a comfortable working process. Such WBPM have been used to supplement patient therapy planning images, usually restricted to regions involved in treatment. Here we report, as an example, the case of a patient treated for prostate cancer whose therapy planning images were complemented by an anatomy model. Although present results are preliminary and our research is ongoing, they appear encouraging, since such patient-adjusted phantoms are crucial in the optimization of radiation protection of patients and for follow-up studies.

Combined regional-general anesthesia: evaluation of remifentanil based general anesthesia and postoperative epidural analgesia.

OBJECTIVES: To evaluate whether remifentanil based general anesthesia combined with epidural analgesia for postoperative pain, has any advantages with respect to consumption of drugs, blood loss, quality of pain control, hemodynamic profile, in major abdominal surgery, as compared to other combined techniques. METHODS: A retrospective study based on chart reviews of patients who have undergone colectomy, radical cystectomy and radical prostatectomy over one year period in our Institution, operated under combined regional-general anesthesia. Twenty-six patients were analyzed and were divided into three groups according to the type of anesthesia received. Group A: combined general-epidural for per-operative and postoperative pain (10 patients). Group B: combined spinal-general anesthesia (8 patients) post-operative analgesia consisted of parenteral mepiridine and paracetamol. Group C: remifentanil based general anesthesia followed by epidural for postoperative analgesia (8 patients). RESULTS: The demographic data, age and M/F distribution were comparable in the three groups. The remifentanil group showed less utilization of muscle relaxant (Cisatracurium) with respect to other groups (p < 0.001). The amount of intraoperative blood loss was not significantly different among the three groups. The efficacy of the postoperative epidural analgesia was demonstrated by the minimal utilization of analgesics (p < 0.05 and 0.01) in group A and C as compared to group B. In the group of remifentanil, the blood pressure was more stable and maintained at a systolic of 80-100 mmHg as compared to initial hypotension mainly in group C. CONCLUSION: The use of remifentanil based general anesthesia offers the advantage of non-accumulation of drugs and hemodynamic stability. Post-operative analgesia can be provided by epidural route which proved to be satisfactory in the remifentanil group. The effect on blood loss was not conclusive in this study.

[Method of radiotherapy planning for head and neck tumors using simulated CT images and radiographic data, developed at the Gustave Roussy Institute]. / Méthode utilisée à l'institut Gustave Roussy pour l'établissement des plans de traitement des cancers ORL à partir des images de simulateur-scanneur et du film radiographique de profil.

The paper deals with the recent improvements introduced in the most usual method applied in the Institut Gustave Roussy radiotherapy department for obtaining the anatomical data of patients treated for head and neck tumors. For each of these patients, five to seven transverses slices and a lateral radiographic film are taken from a Mecaserto simulator-CT. The anatomical representation of the patient sagittal plane is carried out from the digitalisation of the radiographic film on a Vidar Vxr-12 Plus film scanner and integrated into the Dosigray dose calculation programme in order to be used as a support for the laying out of the dose distribution in reference to the treatment. The sagittal anatomical representation obtained from the radiographic film digitalisation is compared with the one resulting from the interpolation between a limited number of irregularly-spaced transverse slices taken on the simulator-CT. The method using the simulator-scanner transverse slices and the radiographic film digitalisation represents an interesting alternative for obtaining an anatomy simulation representative of the patient in hospitals where a scanner is not available full-time for the needs of the radiotherapy process.

[Intensity modulation by inverse planning: preliminary results]. / Modulation d'intensité par planification inverse: résultats préliminaires.

An inverse planning algorithm for determining the intensity of modulated beams that generates conformal radiotherapy dose distributions is presented. This algorithm is based on the mathematical analysis of the singular values decomposition. It is integrated in the DOSIGRAY 3D treatment planning software. The dose is calculated by the separation of the primary and scattered radiation. We presented, for a prostate cancer, the modulated intensity profiles and the optimal dose distribution obtained by the inverse optimization software developed and integrated in the treatment planning system. We obtained a region with high doses which geometrically conforms the target volume and spares the neighboring critical structures. This preliminary study showed the feasibility and the managing of the singular value decomposition to generate conformal dose distribution in a clinical environment.