Predicting poor outcome in patients with suspected COVID-19 presenting to the Emergency Department (COVERED) - Development, internal and external validation of a prediction model.

BACKGROUND: A recent systematic review recommends against the use of any of the current COVID-19 prediction models in clinical practice. To enable clinicians to appropriately profile and treat suspected COVID-19 patients at the emergency department (ED), externally validated models that predict poor outcome are desperately needed. OBJECTIVE: Our aims were to identify predictors of poor outcome, defined as mortality or ICU admission within 30 days, in patients presenting to the ED with a clinical suspicion of COVID-19, and to develop and externally validate a prediction model for poor outcome. METHODS: In this prospective, multi-center study, we enrolled suspected COVID-19 patients presenting at the EDs of two hospitals in the Netherlands. We used backward logistic regression to develop a prediction model. We used the area under the curve (AUC), Brier score and pseudo-R2 to assess model performance. The model was externally validated in an Italian cohort. RESULTS: We included 1193 patients between March 12 and May 27 2020, of whom 196 (16.4%) had a poor outcome. We identified 10 predictors of poor outcome: current malignancy (OR 2.774; 95%CI 1.682-4.576), systolic blood pressure (OR 0.981; 95%CI 0.964-0.998), heart rate (OR 1.001; 95%CI 0.97-1.028), respiratory rate (OR 1.078; 95%CI 1.046-1.111), oxygen saturation (OR 0.899; 95%CI 0.850-0.952), body temperature (OR 0.505; 95%CI 0.359-0.710), serum urea (OR 1.404; 95%CI 1.198-1.645), C-reactive protein (OR 1.013; 95%CI 1.001-1.024), lactate dehydrogenase (OR 1.007; 95%CI 1.002-1.013) and SARS-CoV-2 PCR result (OR 2.456; 95%CI 1.526-3.953). The AUC was 0.86 (95%CI 0.83-0.89), with a Brier score of 0.32 and, and R2 of 0.41. The AUC in the external validation in 500 patients was 0.70 (95%CI 0.65-0.75). CONCLUSION: The COVERED risk score showed excellent discriminatory ability, also in an external validation. It may aid clinical decision making, and improve triage at the ED in health care environments with high patient throughputs.

Italian SARS-CoV-2 patients in intensive care: towards an identikit for subjects at risk?

OBJECTIVE: To investigate patient characteristics and factors that increase the risk of being admitted to intensive care and that influence survival in cases of SARS-CoV-2 pneumonia. PATIENTS AND METHODS: One-hundred and ninety-one SARS-CoV-2 patients were admitted to the "Fondazione Poliambulanza di Brescia" Hospital (Brescia, Lombardy, Italy) in the period 1st March 2020 to 11th April 2020. Data on demographics, clinical presentation at admission, co-morbidities, pharmacological treatment, admission to intensive care and death was recorded. Logistic regression and survival analysis were carried out to investigate the risk of being admitted to intensive care and the risk of death. RESULTS: The mean age of the study cohort was 64.6±9.9 years (range 20-88). Median BMI was 28.5±5 kg/m2. Fever (81%) and dyspnea (65%) were the most common symptoms on admission. Most of patients (63%) had at least one co-existing disease. The 157 (82%) patients admitted to intensive care were more likely to be of intermediate age (60-69 years; OR 3.23, 95% CI 1.32-8.38), overweight (OR 2.66, 95% CI 1.02-7.07) or obese (OR 5.63, 95% CI 1.73-21.09) and with lymphocytopenia (OR 2.75, 95% CI 1.17-6.89) than the 34 patients admitted to the ordinary ward. During intensive care, 50% of patients died and their death was associated with older age (HR 2.06, 95% CI 1.07-3.97), obesity (HR 2.23, 95% CI 1.15-4.35) and male gender (HR 1.9, 95% CI 1.02-3.57). CONCLUSIONS: We found that admission to intensive care and poor survival were associated with advanced age and higher body mass index, albeit with differences in statistical significance. Pre-existing diseases and symptoms on admission were not associated with different clinical outcomes. Interestingly, male gender was more prevalent among SARS-CoV-2 patients and was related negatively to survival, but it was not associated with more frequent admission to intensive care.

Risk of pulmonary aspiration with laryngeal mask airway and tracheal tube: analysis on 65 712 procedures with positive pressure ventilation.

We compared the risk of pulmonary aspiration in patients whose lungs were mechanically ventilated through a laryngeal mask airway (35 630 procedures) or tracheal tube (30 082 procedures). Three cases of pulmonary aspiration occurred with the laryngeal mask airway and seven with the tracheal tube. There were no deaths related to pulmonary aspiration. The incidence and outcome of pulmonary aspiration detected in this study were similar to those previously reported. The adjusted odds ratio (OR) for pulmonary aspiration with the laryngeal mask airway was 1.06 (95% CI 0.20-5.62). Unplanned surgery (OR 30.5, 95% CI 8.6-108.9) and male sex (OR 8.6, 95% CI 1.1-68) were associated with an increased risk of aspiration and age < 14 years with a reduced risk (OR 0.21, 95% CI 0.07-0.64). There were contraindications and exclusions to the use of the laryngeal mask airway but in this selected population the use of an laryngeal mask airway was not associated with an increased risk of pulmonary aspiration compared with a tracheal tube.

Resection line involvement after gastric cancer surgery: clinical outcome in nonsurgically retreated patients.

PURPOSE: Resection line infiltration (RLI) after surgical treatment represents an unfavorable prognostic factor in advanced gastric cancer. We performed a retrospective analysis of 89 patients with resection line involvement who did not undergo reoperation. METHODS: On behalf of the Italian Research Group for Gastric Cancer, we present the characteristics and outcome of 89 patients who were submitted to surgical resection for gastric cancer from 1988 to 2001 and did not undergo reoperation because of disease extension or associated pathologies. RESULTS: RLI was significantly higher in patients with T4 tumors and diffuse histological type. Anastomotic leakages were observed in 4.8% of infiltrated esophageal resection margins, whereas 1.9% of infiltrated duodenal resection lines showed duodenal fistulas. Five-year overall survival of patients with RLI was 29%. Prognosis was not affected by RLI in early forms (100% 5-year survival); however, 5-year survival in T2 and T3 stages was significantly lower with respect to the same stages without residual tumor. The influence of RLI on prognosis was confirmed in N0 as well as in N1 and N2 patients. RLI also was an independent prognostic at multivariate analysis (odds ratio = 1.5; 95% confidence interval, 1.08-2.08; P = 0.0144). CONCLUSIONS: RLI significantly affects long-term survival of advanced gastric cancer. The impact on prognosis is independent of lymph node involvement. Patients in good general condition for whom radical surgery is possible should be considered for reoperation.

The prognostic value of N-ratio in patients with gastric cancer: validation in a large, multicenter series.

AIMS: The proportion between metastatic and examined lymph nodes (N-ratio) has been proposed as an independent prognostic factor in patients with gastric cancer. In the present work we validated the reliability of N-ratio in a large, multicenter series. PATIENTS AND METHODS: We retrospectively reviewed the data of 1853 patients who underwent radical resection for gastric carcinoma. Survival of patients with >15 (Group-1, n=1421) and those with < or =15 (Group-2, n=432) lymph nodes examined was separately analyzed in order to evaluate the influence of lymph node dissection on disease staging. N-ratio categories (N-ratio 0, 0%; N-ratio 1, 1-9%; N-ratio 2, 10-25%; N-ratio 3, >25%) were determined by the best cut-off approach. RESULTS: At multivariate analysis, N-ratio (but not TNM N-category) was retained as an independent prognostic factor both in Group-1 and Group-2 (HR for N-ratio 1, N-ratio 2 and N-ratio 3=1.67, 2.96 and 6.59, and 1.56, 2.68 and 4.28, respectively). After a median follow-up of 45.5 months, the 5-year overall survival rates of TNM N0, N1 and N2 patients were significantly different in Group-1 vs Group-2. This was not the case when adopting the N-ratio classification, suggesting that a low number of excised lymph nodes can lead to patients being understaged using the N-category, but not N-ratio. Moreover, N-ratio identified subsets of patients with significantly different survival rates within TNM N1 and N2 categories in both groups. CONCLUSIONS: N-ratio is a simple and reproducible prognostic tool that can stratify patients with gastric cancer, including those cases with limited lymph node dissection. These data support the rationale to propose the implementation of N-ratio into the current TNM staging system.

Effect of tidal volume and respiratory rate on the power of breathing calculation.

BACKGROUND: The power of breathing (PoB) is used to estimate the mechanical workload of the respiratory system. Aim of this study was to investigate the effect of different tidal volume-respiratory rate combinations on the PoB when the elastic load is constant. In order to assure strict control of the experimental conditions, the PoB was calculated on an airway pressure-volume curve in mechanically ventilated patients. METHODS: Ten patients received three different tidal volume-respiratory rate combinations while minute ventilation was constant. Respiratory mechanics, PoB and its elastic and resistive components were calculated. Alternative methods to estimate the elastic workload were assessed: elastic work of breathing per litre per minute, elastic workload index (the square root of elastic work of breathing multiplied by respiratory rate) and elastic double product of the respiratory system (the elastic pressure multiplied by respiratory rate). RESULTS: Despite constant elastance and minute ventilation, the elastic PoB showed an increment greater than 200% from the lower to the greater tidal volume, accounting for approximately 80% of the whole PoB increment. On the contrary, elastic work of breathing per litre per minute, elastic workload index and elastic double product did not change. CONCLUSION: Changes in breathing pattern markedly affect the PoB despite constant mechanical load. Other indexes could assess the elastic workload without tidal volume dependence. Power of breathing use should be avoided to compare different mechanical loads or efficiencies of the respiratory muscles when tidal volume is variable.

Effect of breathing pattern on the pressure-time product calculation.

BACKGROUND: The pressure-time product (PTP) is often used to compare conditions with different breathing patterns. Being the pressure-time product calculated with pressures changes over a minute, mechanical load and inspiration time per minute should be its main determinants. The aim of this study was to investigate if the method of PTP computation is affected by the breathing pattern when mechanical load and inspiratory time per minute are constant. METHODS: Respiratory mechanics and the PTP developed by the ventilator were calculated in 10 mechanically ventilated patients at three different respiratory rate/tidal volume combinations, provided that minute ventilation and inspiratory time per minute were constant. RESULTS: The static elastance did not change at different tidal volumes. Despite the constant elastic load over a minute, the elastic PTP showed an increment greater than 200% from the higher to the lower respiratory rate, responsible for approximately 80% of the whole PTP increment. On the contrary a 'corrected' elastic PTP (calculated using the square root of the elastic pressure-time area), the elastic double product of the respiratory system and the mean elastic pressure per minute, did not significantly change. CONCLUSIONS: Changes in breathing pattern markedly affected the PTP independently by the mechanical load and the inspiratory time per minute. In these conditions it could not correctly estimate the metabolic cost of breathing. The use of a 'corrected' PTP, the mean inspiratory pressure per minute or the double product of the respiratory system, could overcome this limitation.

[Isolated jejunal rupture after closed thoraco-abdominal trauma]. / Rottura isolata del digiuno dopo trauma chiuso toraco-addominale.

INTRODUCTION: Short bowel disruption following blunt abdominal trauma is rare and hard to diagnose and to treat. Death rate depends both on timing of surgical procedure and on associated lesions. MATERIAL AND METHODS: We show a case of short bowel isolated lesion following fall from mountain bike, III degree in O.I.S. Classification. Abdominopelvic US and helicoidal CT scan were performed, reveling pneumoperitonaeum due to hollow viscus disruption. Surgical procedure was performed within five hours from trauma. RESULTS: No complications occurred in postoperative period. Upper alimentary tract X-ray proved a regular transit, without any fistula. Patient was discharged on 13th day. CONCLUSION: Laparotomy must not be delayed if there is any doubt about bowel conditions: it's demonstrated that timing of surgical procedure is related to prognosis. If haemodynamic status of the patient allows, careful abdomen CT evaluation is mandatory; adequate nutritional support in postoperative period is also very important.

Resistive load of laryngeal mask airway and ProSeal laryngeal mask airway in mechanically ventilated patients.

BACKGROUND: The ProSeal Laryngeal Mask Airway (PLMA) ventilation tube is narrower and shorter than the standard Laryngeal Mask Airway (LMA) and is without the vertical bars at the end of the tube. In this randomized, crossover study, PLMA and LMA resistances were compared. METHODS: Respiratory mechanics was calculated in 26 anesthetized, mechanically ventilated patients with both LMA and PLMA. The laryngeal mask positioning was fiberoptically evaluated. Differences in the respiratory mechanics of the LMA and the PLMA were attributed to the differences between the laryngeal masks. RESULTS: In the total study population the airway resistance was 1.5 +/- 2.6 hPa.l-1.s-1 (P = 0.005) higher with the PLMA than with the LMA. During the PLMA use, the peak expiratory flow reduced by 0.02 +/- 0.05 l min-1 (P = 0.046), the expiratory resistance increased by 0.6 +/- 1.3 hPa.l-1.s-1 (P = 0.022), and the time constant of respiratory system lengthened by 0.09 +/- 0.18 s (P = 0.023). These differences doubled when the LMA was better positioned than the PLMA, whereas they disappeared when the PLMA was positioned better than the LMA. CONCLUSIONS: The standard LMA offers a lower resistive load than the PLMA. Moreover, the fitting between the laryngeal masks and the larynx, as fiberoptically evaluated, plays a major role in determining the resistive properties of these devices.

Comparison of the standard laryngeal mask airway and the ProSeal laryngeal mask airway in obese patients.

BACKGROUND: The ProSeal laryngeal mask airway (PLMA) may have advantages over the laryngeal mask airway (LMA) in obese patients. We tested this hypothesis in a clinical setting. METHODS: Sixty obese patients (BMI >30) were randomized to receive mechanical ventilation (tidal volume 7 ml kg(-1), PEEP 10 cm H(2)O), through either the PLMA or the LMA. A gastric tube was used in all patients. Cuff pressure was set at 60 cm H(2)O and increased progressively until excessive leak occurred. The incidence of sore throat was assessed at recovery and after 1 week. RESULTS: The mean leak fraction was 6.1 (SD 2.9)% with the LMA and 6.4 (3.5)% with the PLMA (P=0.721). With the PLMA, with no sign of ventilation problems, the drainage tube was not patent in three patients. The cuff pressure was >100 cm H(2)O in 38% of the LMA group and 7% of the PLMA group (P=0.05). The incidence of sore throat was similar in both groups and it was similarly scored in the recovery room and 1 week after surgery. CONCLUSIONS: Both the PLMA and the LMA can be used for mechanical ventilation of obese patients. The patency of the PLMA drainage tube needs to be checked constantly even when an optimal airtight seal is present. In obese patients the LMA requires a greater cuff pressure than the PLMA, but sore throat is not related to the cuff pressure. Sore throat assessment in the recovery room appears as reliable as assessment later.

Impact of laryngeal mask airway and tracheal tube on pulmonary function during the early postoperative period.

BACKGROUND: The tracheal tube (TT) produces reversible bronchoconstriction and increases pulmonary airway resistance compared to the laryngeal mask airway (LMA). The possible persistence of this effect in the postoperative period has not been studied. The aim of this study was to compare the early postoperative pulmonary function in healthy patients undergoing minor surgical procedures with the LMA or with the TT. METHODS: Sixty patients scheduled for saphenous vein stripping under general anaesthesia were randomised to receive the LMA or the TT. Before anaesthesia and 20 min after LMA or TT removal, pulse oxymetry values (SpO(2)) were recorded and patients performed forced spirometry in the supine position. RESULTS: Preoperative pulmonary function was normal in both groups. There were no differences between groups in the preoperative respiratory function test and SpO(2). Following surgery SpO(2), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC) and peak expiratory flow (PEF) decreased in both groups. The FEV1/FVC did not change in either of the groups. In the TT group, compared to patients using the LMA, there was a greater relative decrease of SpO(2) (2.7 +/- 2.7% vs. 1.3 +/- 2.2%, P=0.017), FEV1 (17.6 +/- 12.2% vs. 8 +/- 17.4%, P=0.008), FVC (15.8 +/- 12.4% vs. 9 +/- 13.4%, P=0.023) and PEF (20.6% +/- 15.3% vs. 8.1 +/- 33.3%, P=0.033). CONCLUSIONS: This study demonstrates greater early postoperative respiratory restrictive syndrome and lower arterial oxygen saturation following tracheal intubation compared to LMA use in patients without respiratory disease.

Occurrence of Black Dot of Potato Caused by Colletotrichum coccodes in Central Italy.

Between 1997 and 2000, black dot of potato (Solanum tuberosum L.), caused by the polyphagous soilborne fungus Colletotrichum coccodes (Wallr.) Hughes, was observed each summer in fields located in Umbria (central Italy). Disease incidence ranged from 50 to 100%, and early potato cultivars were generally more susceptible than late-maturing ones. Disease symptoms were first observed during August as a yellowing and wilting of foliage in the tops of plants, followed by rotting of the roots and stems, which led to the premature death of 50 to 70% of plants. Setose1 sclerotia (300 to 500 mm in diameter) and acervuli of the fungus were found on roots and stems of infected plants. Acervuli produced hyaline, aseptate, cylindrical conidia (16 to 22 × 2.5 to 4.5 µm) formed on unicellular cylindrical phialidic conidiophores. The fungus was isolated from diseased stems and roots on potato dextrose agar (PDA) at pH 6.5. Pathogenicity of the fungus was confirmed by fulfilling Koch's postulates using 3- to 4-week-old potato plants of a local cultivar. A superficial 5-mm vertical cut was made with a scalpel into the base of potato stems (2 cm beneath the soil surface), and 5-mm-diameter plugs of PDA alone (control plants) or PDA plus fungal growth were placed over the cuts. The wounds were sealed with wet cotton swabs that were held in place with Parafilm. Symptoms that resembled those in the field were observed on inoculated plants 6 to 8 weeks postinoculation. Symptoms did not appear on the control plants. The same fungus was reisolated from the diseased plants. Based on morphological characteristics of sclerotia, acervuli, and conidia, as well as pathogenicity tests, the fungus was identified as C. coccodes. To our knowledge, this is the first report of C. coccodes as the causal agent of black dot of potato in central Italy. We did not observe foliar outbreaks of the disease, which were reported from the United States (2). In both 1921 (1) and 1951 (3), the fungus was reported to cause severe outbreaks of the disease in northern Italy. Since then, its presence in Italy has been rarely recorded in potato (4). The occurrence of extremely dry and hot weather conditions during the summers of 1997 to 2000, which are favorable for disease development, made the disease particularly severe. We cannot exclude the possibility that the disease may have been present in central Italy before our observations, as it can be misdiagnosed and its symptoms can be masked by the symptoms of other diseases. The significance of black dot in central Italy needs to be reappraised in terms of both yield loss and tuber quality. References: (1) C. Arnaudi. Atti Ist. Bot. Univ. Pavia. Ser. 3, 1:71, 1924. (2) A. W. Barkdoll and J. R. Davis. Plant Dis. 76:131, 1992. (3) G. Goidanich. Inf. Fitopatol. 1:5, 1951. (4) S. Vitale et al. J. Plant Pathol. 80:265, 1998.

[Dermatofibrosarcoma protuberans of the breast: a case report]. / Dermatofibrosarcoma protuberans della mammella: descrizione di un caso.

We describe a dermatofibrosarcoma protuberans (DFSP) of the breast and briefly report about such cases previously mentioned in the literature. A 27-year-old woman was referred because of the progressive increase, during pregnancy, of a mammary nodule located between the internal quadrants of the right breast. Its clinical and radiologic features suggested a fibroadenoma. Lumpectomy revealed a 3-cm, gray-whitish, fasciculated nodule. Histological examination showed a neoplasm characterized by a highly and monomorphic cellular proliferation of spindle-shaped cells, arranged in bundles displaying repetitive storiform growth pattern and infiltrating the adjacent mammary tissue. Lack of necrosis and low mitotic rate was observed. At immunohistochemistry the tumor cells were diffusely positive for vimentin and CD34, but negatively stained with CD99, bc-2, desmin, smooth-muscle actin, S100 protein and cytokeratins. A diagnosis of mammary dermatofibrosarcoma protuberans (DF-SP) was posed. Neoplastic involvement of surgical margins led to a subsequent quadrantectomy without regional lymphadenectomy. The patient was alive and disease-free at the 8-month follow-up. Mammary DFSP is rare. Its preoperative diagnosis is extremely difficult, particularly when radiologic images show an intraparenchymal lesion with round borders. We report such a case and briefly review the pertinent literature. Morphologic parameters to distinguish DFSP from other spindle cell lesions of the breast are discussed.

Pressure controlled versus volume controlled ventilation with laryngeal mask airway.

STUDY OBJECTIVE: To quantify the impact on peak airway pressure of pressure-controlled and volume-controlled ventilation during Laryngeal Mask Airway (LMA) use. DESIGN: Prospective, crossover clinical study. SETTING: University-affiliated hospital. PATIENTS: 32 ASA physical status I and II patients undergoing general anesthesia with the LMA. INTERVENTIONS: Patients were ventilated for three minutes both with pressure-controlled and volume-controlled ventilation, provided that tidal volume (V(T) ) and inspiratory time (It) were constant. MEASUREMENTS AND MAIN RESULTS: The monitored parameters were electrocardiography, arterial blood pressure, pulse oximetry, capnography, neuromuscular transmission, airway pressure and flow, and concentration of ventilated vapors and gases. The actually delivered V(T) was similar with both types of ventilation (volume-controlled = 0.67 +/- 0.13 lt, pressure-controlled = 0.67 +/- 0.14 lt; p = 0.688). Peak airway pressure was lower during pressure-controlled ventilation (14.6 +/- 3.5 cmH(2)O) than during volume-controlled ventilation (16 +/- 4 cmH(2)O) (p < 0.001). Furthermore, we noted that the higher the airway pressure with volume-controlled ventilation, the greater was the reduction in airway pressure during pressure-controlled ventilation. CONCLUSIONS: Pressure-controlled rather than volume-controlled ventilation can improve the effectiveness of mechanical ventilation in patients with high airway pressure.

Endorectal sonographic appearances of rectal MALT lymphoma, its response to therapy, and local recurrence.

Endorectal sonography may significantly help to evaluate rectal lymphoma. We report the sonographic findings in a case of rectal non-Hodgkin's MALT (mucosa-associated lymphoid tissue) lymphoma, including the monitoring of response to therapy and confirmation of recurrence, in a 45-year-old man. On endorectal sonography of the rectal wall, the mucosa was markedly thickened to 1.1 cm and was diffusely hypoechoic and risen into multiple polypoid folds. The submucosa and muscularis propria appeared normal. Multiple lymph nodes were visualized in the perirectal fat; they were homogeneously hypoechoic, were round or oval, and ranged from 1.0 cm to 2.6 cm. Endoscopic biopsies revealed a grade I non-Hodgkin's MALT lymphoma. Following chemotherapy, endorectal sonography showed that the surface of the rectal mucosa had a smoother appearance and near-normal thickness, but lymph nodes, although smaller, remained visible in the perirectal fat. Four months later, endorectal sonography demonstrated a local relapse of disease, with significant thickening of the rectal mucosa and multiple lymph nodes visible in the perirectal fat. Following high-dose chemotherapy for the recurrence, endorectal sonography demonstrated a near-normal appearance of the rectal mucosa.

Acute respiratory acidosis does not increase plasma potassium in normokalaemic anaesthetized patients. A controlled randomized trial.

BACKGROUND AND OBJECTIVE: Few and conflicting data are available regarding the changes of plasma potassium concentration during acute respiratory acidosis in human beings. This study compares the acute changes in plasma potassium concentration in acutely hypercapnic patients and in non-hypercapnic patients during general anaesthesia. METHODS: Thirty-three patients undergoing interventional rigid bronchoscopy were studied. Ventilation of the lungs was randomly conducted using either spontaneous-assisted ventilation or intermittent negative-pressure ventilation. All patients received the same anaesthetic protocol. Arterial blood gases and osmolality, and plasma concentrations of glucose, sodium, potassium and chloride were measured. RESULTS: Intraoperatively, PaCO2 was higher during spontaneous-assisted ventilation than during intermittent negative-pressure ventilation (9 +/- 1.8 vs. 5.4 +/- 1.2 kPa, P < 0.001) and the pH was also lower during spontaneous-assisted ventilation than during intermittent negative-pressure ventilation (7.24 +/- 0.07 vs. 7.4 +/- 0.08, P < 0.001). Plasma potassium concentration remained similar in both groups (3.8 +/- 0.2 mmol L(-1) with spontaneous-assisted ventilation vs. 3.7 +/- 0.4 mmol L(-1) with intermittent negative-pressure ventilation). CONCLUSION: Acute respiratory acidosis does not affect plasma potassium concentration.

Usefulness of endorectal ultrasound after preoperative radiotherapy in rectal cancer: comparison between sonographic and histopathologic changes.

PURPOSE: Our aim was to assess the advantages of endorectal ultrasound after preoperative radiotherapy in rectal cancer, its reliability in tumoral staging, and its capacity to identify completely sterilized lesions. METHODS: From 1994 to 1997, 29 patients with rectal cancer were systematically subjected to endorectal ultrasound before and after preoperative radiotherapy. Each patient was administered 30 to 50 Gy, followed by surgery six to eight weeks after completion of radiotherapy. Endorectal ultrasound was performed using a biplanar (linear and sectorial) endorectal probe. The morphologic, quantitative, and echo-pattern changes of the irradiated tumor were examined. Results of ultrasound findings before and after radiotherapy and a histologic examination of the surgical specimens were compared. Histopathologic studies were used to evaluate macromicroscopical radiation-induced changes, case by case. A comparison between tumoral shrinkage and fibrotic replacement was made using the semiquantitative Dworak's method. RESULTS: Morphologically and quantitatively, postradiation endorectal ultrasound showed the reappearance of anatomic cleavage planes, a considerable shrinkage of the tumor, and in low rectal tumors, an increase in the distance from the anorectal ring in more than 50 percent of the cases. These data had a direct influence on surgical treatment. Histologic examination showed that, in 28 out of 29 cases, fibrosis was the most dominant component of the irradiated lesions, varying by more than 50 to 100 percent of the lesion (four cases pTO). A comparison of postradiation endorectal ultrasound with histopathology revealed that fibrosis became the morphologic basis of ultrasound images; therefore, after radiotherapy, what endorectal ultrasound staged was no longer the tumor but the extent of fibrosis in the rectal wall. A histopathologic examination showed that the residual tumor, when present, was always within the fibrosis, never outside or separate from it. Postradiation endorectal ultrasound showed echo-pattern changes. Some of the changes (more echogenic and nonhomogeneous lesions) were histologically related to the persistence of the tumor to a considerable degree; other changes (reappearance of parietal layers) were related to complete sterilization of lesions in two of three cases. CONCLUSIONS: From the morphologic and quantitative point of view, postradiation endorectal ultrasound provides oncologists and surgeons useful information to assess treatment effectiveness and plan the surgical approach. From the tumor staging point of view, our report presents a completely new concept: that six to eight weeks after radiotherapy, endorectal ultrasound no longer stages the tumor, but rather the fibrosis that takes its place. However, postradiation endorectal ultrasound is a valid tool, because the extent of fibrosis in the rectal wall is a direct indication of the depth of residual cancer. A residual tumor, when present, is always inside the fibrosis. Finally, however, as regards the capacity of endorectal ultrasound to exclude or indicate complete sterilization of the lesion, the actual significance of the echo-pattern changes we observed needs to be assessed further by studies on a large number of cases.

Negative pressure ventilation vs external high-frequency oscillation during rigid bronchoscopy. A controlled randomized trial.

STUDY OBJECTIVES: To compare the effectiveness of two modalities of external ventilation during rigid bronchoscopy: intermittent negative pressure ventilation (INPV) and external high-frequency oscillation (EHFO). DESIGN: Prospective, controlled, randomized, nonblinded study. SETTING: University-affiliated hospital. PATIENTS: Seventy patients undergoing interventional rigid bronchoscopy for tracheobronchial lesions were enrolled into the study. INTERVENTIONS: Mechanical ventilation was performed by INPV or EHFO. When pulse oximetry was < 90%, manually assisted ventilation was delivered. MEASUREMENTS AND RESULTS: Arterial blood gases were sampled preoperatively and intraoperatively. Most patients in both groups had normal intraoperative PaCO(2) (mean, 43. 6 +/- 11.8 mm Hg under EHFO and 37.4 +/- 8.2 mm Hg under INPV; p = 0.012), and acidemia occurred in 9 of 35 patients of EHFO group and in 2 of 35 patients of INPV group (p = 0.049). Hypercapnia (PaCO(2) > 50 mm Hg) was observed in 10 patients under EHFO and in 2 with INPV (p = 0.026). Intraoperative mean PaO(2) was similar (101.4 +/- 52.9 mm Hg with EHFO and 124.2 +/- 50.3 mm Hg with INPV; p = 0.07), but O(2) supply was different (3.5 +/- 2.3 L/min during INPV and 8.5 +/- 6.2 L/min during EHFO; p < 0.001). Intraoperative hypoxemia (PaO(2) < 60 mm Hg) occurred in five patients with EHFO and two with INPV (p = 0.426). Three EHFO patients required manually assisted ventilation (mean, 0.2 +/- 0.9), but no INPV patient did (p = 0.142). CONCLUSIONS: External negative pressure ventilation appears to be a suitable choice during rigid bronchoscopy: both EHFO and INPV ensure effective ventilation and comfortable operating conditions in the majority of patients. Some patients may receive inadequate ventilation with EHFO, developing respiratory acidosis and requiring manually assisted ventilation. In comparison with INPV, EHFO requires a higher fraction of inspired oxygen.