Comparison of B-mode ultrasound and computed tomography in the diagnosis of maxillary sinusitis in mechanically ventilated patients

Multicenter Observational Study to Evaluate the Diagnostic Value of Sonography in Patients with Chronic Rhinosinusitis

(1) Background: Computed tomography (CT) is considered mandatory for assessing the extent of pathologies in the paranasal sinuses (PNS) in chronic rhinosinusitis (CRS). However, there are few evidence-based data on the value of ultrasound (US) in CRS. This multicenter approach aimed to compare diagnostic imaging modalities in relation to findings during surgery. (2) Methods: 127 patients with CRS were included in this prospective multicenter study. Patients received preoperative US and CT scans. The sensitivity and specificity of CT and US were extrapolated from intraoperative data. (3) Results: CT scans showed the highest sensitivity (97%) and specificity (67%) in assessing CRS. Sensitivities of B-scan US were significantly lower regarding the maxillary sinus (88%), the ethmoid sinus (53%), and the frontal sinus (45%). The highest overall sensitivity was observed for assessing the pathology of the maxillary sinus. (4) Conclusions: We observed high accuracy with CT, confirming its importance in preoperative imaging in CRS. Despite the high US expertise of all investigators and a standardized examination protocol, the validity of CT was significantly higher than US. Ultrasound of the PNS sinuses is applicable in everyday clinical practice but lacks diagnostic accuracy. Nevertheless, it might serve as a complementary hands-on screening tool to directly correlate the clinical findings in patients with PNS disease.

Usefulness of ultrasound in the diagnosis of nosocomial maxillary sinusitis in patients with severe Covid-19 pneumonia: a retrospective study

Purpose

Severe Covid-19 pneumonia frequently presents with infective complications as bacterial and fungal infections, nosocomial maxillary sinusitis is one of them. We describe the role of ultrasonography in the diagnosis of nosocomial maxillary sinusitis in patients undergoing mechanical ventilation due to severe Covid-19 pneumonia.

Methods

Patients with severe pneumonia due to Covid-19 requiring mechanical ventilation and had maxillary sinus occupation by ultrasonography were retrospectively enrolled at intensive care unit of Sanatorio De los Arcos, Buenos Aires, Argentina, between March 2020 and May 2021.

Results

We evaluated a total of 171 patients with severe Covid-19 pneumonia requiring mechanical ventilation during the study period. We included 26 patients that had maxillary sinus occupation by ultrasonography (15.2%). Out of the 26 patients, in 17 the diagnosis was confirmed by surgical drainage of the maxillary sinus with positive cultures with a positive predictive value of 85%. In 34.6% of the cases the maxillary sinus disease was unilateral and in 38.4% bilateral. A sinus computed tomography (CT) was performed in 30.7% of the patients. Most of the patients underwent to surgical drainage without a CT scan (66.7%).

Conclusions

Ultrasonography is a useful tool for the detection of maxillary sinus infection in patients with severe Covid-19 pneumonia and avoids to perform a CT scan and, therefore, unnecessary transfers.

Ultrasonographic assessment of airway

Ultrasound is gaining increasing popularity among anesthesiologists as it is readily available and provides real-time imaging for various procedures. It is considered as a “visual stethoscope” of the anesthesiologist. After establishing its use in regional blocks and central venous catheter insertion, it is now finding increasing use in anticipation of difficult airway and securing and maintaining it. It has challenged the classical approach of clinical assessment of airway and allows more dynamic bedside assessment. This article attempts to briefly outline the role of ultrasound and its applications for airway management in patients.

Otolaryngology in Critical Care

Diseases affecting the ear, nose, and throat are prevalent in intensive care settings and often require combined medical and surgical management. Upper airway occlusion can occur as a result of malignant tumor growth, allergic reactions, and bleeding events and may require close monitoring and interventions by intensivists, sometimes necessitating surgical management. With the increased prevalence of immunocompromised patients, aggressive infections of the head and neck likewise require prompt recognition and treatment. In addition, procedure-specific complications of major otolaryngologic procedures can be highly morbid, necessitating vigilant postoperative monitoring. For optimal outcomes, intensivists need a broad understanding of the pathophysiology and management of life-threatening otolaryngologic disease.

Alternative diagnosis in the putative ventilator-associated pneumonia patient not meeting lavage-based diagnostic criteria

BACKGROUND

The clinical picture of ventilator-associated pneumonia (VAP) can be mimicked by other infectious and non-infectious diseases. The aim of this study was to determine the alternative diagnoses and to develop a diagnostic flow chart for patients suspected of having VAP not meeting the diagnostic broncho-alveolar lavage (BAL) criteria.

METHODS

Adult intensive care patients with a clinical suspicion of VAP and negative BAL results were included. The clinical suspicion of VAP was based on the combination of clinical, radiological, and microbiological criteria. BAL was considered positive if cell differentiation revealed ≥ 2% cells with intracellular organisms and/or quantitative culture results of ≥ 10(4) cfu/ml. The most likely alternative diagnosis of fever and pulmonary densities was retrospectively determined by two authors independently.

RESULTS

In all, 110 of 207 patients with suspected VAP did not meet the diagnostic BAL criteria and required further diagnostic evaluation. In 67 patients an alternative diagnosis for fever could be found. In 51 patients an alternative diagnosis of both fever and pulmonary densities could be established. In almost 40% of patients no alternative diagnosis could be provided. Non-bacterial pneumonia was diagnosed in 10 patients with Herpes simplex virus 1 (HSV-1) as the most common pathogen. In eight patients non-infectious pneumonitis was diagnosed.

CONCLUSION

Due to the wide range of alternative diagnoses and applied tests the diagnostic work-up proved to be necessarily individualized and guided by repeated clinical assessment. The most frequently found alternative diagnoses were viral pneumonia and non-infectious pneumonitis.

Sonography for diagnosis of benign and malignant tumors of the nose and paranasal sinuses

OBJECTIVES

The purpose of this study was to demonstrate the reliability of sonography for diagnosis of nose and paranasal sinus tumors.

METHODS

Ninety-six consecutive patients with tumors underwent sonography and computed tomography (CT) before surgical treatment. Tumor detectability and imaging findings were evaluated independently and then compared with pathologic findings.

RESULTS

Of 96 tumors, 75 were detected by sonography, for a detectability rate of 78.1%; 93 tumors were detected by CT, for a detectability rate of 96.9%. By comparison, sonography showed a trend toward higher detectability of nasal vestibular tumors than CT (87.5% for sonography versus 50.0% for CT) and small lumps on the wing of the nose (78.8% for sonography versus 33.3% for CT). Among the sonographic features, boundary, shape, internal echo, calcification, bone invasion, vascular pattern, and cervical lymph node metastasis all had significantly positive correlations with malignancy (P < .05), but size did not (P = .324). In addition, the vascular resistive index for malignant tumors was significantly higher (mean ± SD, 0.66 ± 0.20) than the index for benign lesions (0.24 ± 0.30; P < .001). Moreover, the detection rate for grade 1-3 (small-large) blood flow in benign lesions was only 43.8%, whereas the rate for malignant tumors was 97.7% (P < .001).

CONCLUSIONS

The vascular pattern may be a promising predictive indicator for distinguishing benign and malignant tumors of the nose and paranasal sinuses. Consequently, sonography has high value for diagnosis of benign and malignant tumors of the nose and paranasal sinuses, especially for nasal vestibular tumors and small lumps on the wing of the nose.

[Comparison of B-mode ultrasonography and computed tomography in the evaluation of maxillary sinusitis in pediatric patients]

The use of ultrasonography in the diagnosis of maxillary sinusitis in pediatric patients has been reported recently because of the improvement of the accuracy of ultrasound technology. We thus compared B-mode ultrasonography and computed tomography in the diagnosis of maxillary sinusitis in pediatric patients. Thirty-six maxillary sinuses in 18 patients (10 females, 8 males, ages ranging from 7-15 years with an average age of 10.4 years) were examined. Ultrasonography of the maxillary sinus was performed in the horizontal and the vertical direction. Paranasal computed tomography and B-mode ultrasonography were performed within a few days. In some of these patients the maxillary sinuses were examined with a fiberscope. Sensitivity, specificity, false-positive, false-negative, positive predictive value and negative predictive value of B-mode ultrasonography compared with computed tomography were 92.6%, 100%, 0%, 7.4%, 100% and 81.8%, respectively. It appeared that ultrasonography was more sensitive than X-ray imaging, because the sensitivity and specificity of X-ray imaging of the maxillary sinus in pediatric patients compared with CT was reportedly 70-80%. A meaningful correlation of ultrasonography and CT was accepted as an assessment of desease severity. There are some problems with diagnosis by ultrasonography. There is no differentiation of mucosal thicking, cyst and discharge and imaging are less useful in pediatric patients. Because of these reasons, clinical sign and views in the nose are important for a correct diagnosis in pediatric patients. Furthermore, the most suitable age range to diagnose maxillary sinusitis correctly in pediatric patients must be examined.

Application of radiographic images in diagnosis and treatment of deep neck infections with necrotizing fasciitis: a case report

The advent and wide use of antibiotics have decreased the incidence of deep neck infection. When a deep neck infection does occur, however, it can be the cause of significant morbidity and death, resulting in airway obstruction, mediastinitis, pericarditis, epidural abscesses, and major vessel erosion. In our clinic, a patient with diffuse chronic osteomyelitis of mandible and fascial space abscess and necrotic fasciitis due to odontogenic infection at the time of first visit came. We successfully treated the patient by early diagnosis using contrast-enhanced CT and follow up dressing through the appropriate use of radiographic images.

Comparison of preoperative computed tomography and surgical findings in maxillofacial infections

PURPOSE

To examine the accuracy of computed tomography (CT) in predicting the presence of surgically confirmed abscess in patients presenting with deep maxillofacial infections (DMIs).

MATERIALS AND METHODS

The medical records of 36 patients with clinically suspected DMI were reviewed. All patients underwent preoperative CT scan to determine whether abscess or cellulitis was present. The operative reports of all patients were compared with their preoperative CT scan findings.

RESULTS

Of 36 patients, 30 had abscess predicted by preoperative CT scan. The positive predictive value for DMI based on CT findings interpreted by an oral surgeon and confirmed as an abscess at operation was 90%, whereas the negative predictive value was 33%. When findings were interpreted by a radiologist, the positive predictive value was 94.1% whereas the negative predictive value was 26.3%. Thirty patients had abscess predicted by preoperative CT scan when interpreted by an oral surgeon, whereas seventeen had abscess predicted by a radiologist. At operation, 3 of 30 patients had cellulitis whereas 27 had abscess, for a false-positive rate of 60% and false-negative rate of 12.9%. On the basis of preoperative radiography, 1 of 17 patients had cellulitis whereas 16 had abscess, for a false-positive rate of 16.7% and a false-negative rate of 46.7%. The agreement between CT and operative findings in predicting abscess by an oral surgeon was 80.6% and by a radiologist was 58.3%.

CONCLUSION

CT yielded high sensitivity for the detection of DMI abscess but poor specificity, likely because of the paucity of cellulitis.

Maxillary sinusitis in patients ventilated for a severe head injury and with nostrils free of any foreign body

BACKGROUND

This study aims to determine the frequency of maxillary sinusitis in the patients with traumatic head injury and nostrils free of any foreign body. In addition, the sensitivity and specificity of ultrasonography (US) for the detection of the presence of fluid in maxillary sinuses were evaluated.

PATIENTS AND METHODS

Forty patients with severe traumatic head injury were included in the study. The patients who had displaced maxillary sinus fracture at the medial wall and naso-tracheal and/or naso-gastric tube were excluded. Paranasal computed tomography (CT) was performed along with the routine cranial CT scanning or in case of unknown source of infection and compared with the results of ultrasonographic examination of maxillary sinuses performed by a single radiologist who was unaware of the CT results. In the patients, who had clinical and radiological signs of sinusitis, a trans-nasal puncture was performed using sinoject (SinoJect, ATOS Medical, Sweden), a spring-activated puncture instrument, to take a sample for microbiologic examination and to drain maxillary sinuses.

RESULTS

Eighty-five percent of the patients were tracheotomised on the fifth day (on average) of their intensive care unit (ICU) stay. The frequency of sinusitis in the study group was found to be 32.5% (13 patients). The most frequently isolated species were Pseudomonas spp. (37.5%), Escherichia coli (20.8%) and Peptostreptococcus (16.7%). Five of the aspirates were polymicrobial. The sensitivity, specificity, positive predictive value and negative predictive value of B-mode US, compared with CT for the detection of fluid presence in maxillary sinuses in a 100 maxillary sinus examinations, were 92.2%, 81.6%, 83.9% and 90.9%, respectively.

CONCLUSION

Maxillary sinusitis should be considered as a source of infection or sepsis in patients with traumatic head injury because of its high frequency. US is likely to be used as the first-line diagnostic tool for the determination of fluid in maxillary sinuses, especially in patients who do not require CT or cannot be transported to a radiology unit for CT.

Antral computerized tomography pre-operative evaluation: relationship between mucosal thickening and maxillary sinus function

OBJECTIVES

to assess the correlation between maxillary sinus inferior mucosal thickening and sinus outflow obstruction.

MATERIAL AND METHODS

the study included 280 computerized tomography (CT) scans (560 maxillary sinuses). CT aimed to assess sinusitis; trauma to the face and intubated patients were excluded. Mucosal thickening was graded as < 5 mm (1), < 10 mm (2), < 15 mm (3), < 20 mm (4) and > 20 mm (5), and classified by appearance as normal, rounded, circumferential, irregular, or complete. Maxillary sinus outflow was classified as patent or obstructed.

RESULTS

mucosal thickening was found in 36.1% of the maxillary sinuses, graded as 31.2% (1), 34.2% (2), 12.9% (3), 5.4% (4) and 16.3% (5), and classified as rounded (11.8%), irregular (10.4%), circumferential (8.8%) and complete (5.2%). Sinus outflow was obstructed in 15% of the scans. Mucosal thickening of < 5 mm (11.1%), < 10 mm (36.2%) and > 10 mm (74.3%) was associated with sinus obstruction (P<0.0001). Rounded (6.1%), circumferential (55.2%), irregular (38.8%) and complete (100%) mucosal appearances were associated with sinus obstruction (P<0.001). When statistically combined, a substantial risk for sinus obstruction was observed with irregular mucosal appearance of > 5 mm (56.5% for grade 2 up to 82.6% for grades 3-5) and circumferential appearance (21.4% for grade 1 up to 100% for grades 3-5). A low risk for obstruction was found with the rounded appearance (mean 6.1%).

CONCLUSIONS

irregular (> 5 mm), circumferential and complete mucosal appearance are associated with an increased risk for sinus outflow obstruction and an ENT consultation is recommended. A rounded mucosal appearance of any grade is associated with a low risk for sinus obstruction. Routine CT scans, including the maxillary sinus ostium, are recommended.

Diagnosis and management of chronic rhinosinusitis in adults

Chronic rhinosinusitis (CRS) is characterized by mucosal inflammation affecting both the nasal cavity and paranasal sinuses; its causes are potentially numerous, disparate, and frequently overlapping. The more common conditions that are associated with CRS are perennial allergic and nonallergic rhinitis, nasal polyps, and anatomical mechanical obstruction (septum/turbinate issues). Other less common etiologies include inflammation (eg, from superantigens), fungal sinusitis or bacterial sinusitis with or without associated biofilm formation, gastroesophageal reflux, smoke and other environmental exposures, immune deficiencies, genetics, and aspirin-exacerbated respiratory disease. A diagnosis of CRS is strongly suggested by a history of symptoms (eg, congestion and/or fullness; nasal obstruction, blockage, discharge, and/or purulence; discolored postnasal discharge; hyposmia/anosmia; facial pain and/or pressure) and their duration for > 3 months. A definitive diagnosis requires physical evidence of mucosal swelling or discharge appreciated during physical examination coupled with CT imaging if inflammation does not involve the middle meatus or ethmoid bulla. Multivariant causation makes the diagnosis of CRS and selection of treatment complex. Furthermore, various types of health care providers including ear, nose, and throat (ENT) specialists, allergists, primary care physicians, and pulmonologists treat CRS, and each is likely to have a different approach. A structured approach to the diagnosis and management of CRS can help streamline and standardize care no matter where patients present for evaluation and treatment. A 2008 Working Group on CRS in Adults, supported by the American Academy of Otolaryngic Allergy (AAOA), developed a series of algorithms for the differential diagnosis and treatment of CRS in adults, based on the evolving understanding of CRS as an inflammatory disease. The algorithms presented in this paper address an approach for all CRS patients as well as approaches for those with nasal polyps, edema observed on nasal endoscopy, purulence observed on nasal endoscopy, an abnormal history and physical examination, and an abnormal history and normal physical examination.

Ventilator-Associated Pneumonia

The area of the alveolar epithelium of the lung is approximately 70 m². This area is constantly in contact with the ambient air and is therefore vulnerable to contamination with airborne microbes and particles of respirable size. Due to the configuration of the respiratory tract, airborne particles having diameters in the range of 0.5-2.0 μ can reach and deposit in the terminal part of the tracheobronchial tree - most bacteria are of this size. In reality, very few bacteria cause infections by spreading via the airborne route (e.g., mycobacteria, viruses, and legionella). Most bacteria cause pneumonia by first colonizing the upper respiratory tract and later descending into the tracheobronchial tree.

Whole-body ultrasound in the intensive care unit: a new role for an aged technique

Management of critically ill patients requires rapid and safe diagnostic techniques. Ultrasonography has become an indispensable tool that supplements physical examination in the intensive care unit. It enables early recognition of neurological emergencies, assists the diagnosis of abdominal and lung pathologies, and provides real-time information on the cardiac performance of critically ill patients. Furthermore, it detects possible infectious sites and renders therapeutic invasive procedures more convenient and less complicated. Whole-body ultrasound in the hands of adequately trained intensivists has the ability to reinvigorate the physical examination, without subjecting the patient to excessive irradiation and the risks of transport.

A postural change test improves the prediction of a radiological maxillary sinusitis by ultrasonography in mechanically ventilated patients

OBJECTIVE

The aim of this study was to evaluate a postural change test during sinus ultrasound, compared with CT scan, in case of partial sinusogram to differentiate air-fluid level from mucosal thickening.

DESIGN

Prospective clinical investigation.

SETTING

Medical intensive care unit.

PATIENTS

150 intubated patients.

INTERVENTIONS

Patients were examined by sinus ultrasound in half-sitting position. A partial sinusogram was defined as the sole visualization of the hyperechogenic posterior wall of the sinus. In this situation, a postural change was performed and ultrasound was achieved in supine position. If the partial sinusogram disappeared when the patient was placed in a supine position (positive test), the partial sinusogram was an air-fluid level. If the partial sinusogram did not disappear (negative test), we considered it as a mucosal thickening. The CT and ultrasound were performed on the same day. Radiological maxillary sinusitis (RMS) on CT was defined as the presence of an air-fluid level. Absence of RMS on CT was defined as normal sinus or as the presence of mucosal thickening.

MEASUREMENTS AND RESULTS

300 sinuses were examined. A partial sinusogram was found in 90 sinuses and CT scan confirmed the presence of RMS in 55 sinuses (61%). Sensitivity, specificity, positive predictive value, and negative predictive value of postural change test compared with CT were, respectively, 94.6, 85.6, 91.2 and 90.9%. The positive predictive value increased from 61 to 91.2% after the postural change test.

CONCLUSIONS

In case of a partial sinusogram, a postural change increases the accuracy of ultrasound to diagnose RMS.

Point-of-care ultrasound: Infection control in the intensive care unit

Ultrasound provides a diagnostic modality that allows a whole-body approach at the bedside of a critically ill patient in the search for infectious foci. Both common sites of infection, such as the lung and pleura, central veins, and maxillary sinuses, and also less common sites, such as gastrointestinal perforation, sepsis due to mesenteric ischemia, or even meningitis, provide characteristic ultrasound patterns. Optimal use of ultrasound also combines bedside diagnosis with subsequent interventional procedures that can decrease the need for transfer to other imaging and interventional suites. Experience has shown that fevers of unknown origin in the critical care unit often have ultrasound equivalents. Thus, if a comprehensive ultrasound examination is negative, it is now appropriate to speak of fever of unknown sonographic origin.

Sinusitis nosocomial en la Unidad de Cuidados Intensivos: incidencia, características clínicas y evolución

OBJECTIVE

To describe incidence, epidemiologic characteristics, clinical manifestations, tomographic features, microbiologic findings and evolution of patients with nosocomial sinusitis (NS) in an Intensive Care Unit (ICU).

DESIGN

Retrospective and descriptive study.

SETTING

24-bed ICU from a public hospital.

PATIENTS

Patients admitted to the ICU for more than 48 hours who fulfilled CDC criteria of NS.

RESULTS

We found 18 cases of NS, that accounts for an incidence of 1.1% of all admitted patients. Average age was 46.3 +/- 18.3 years, with a predominance of males (89%): Average APACHE II was 20.2 +/- 6.3. All the cases had endotracheal intubation and 89% had a nasogastric tube. All the patients had fever and 83% purulent rhinorrhea or oral secretions. The maxillary sinus was the most affected (72%) followed by ethmoidal sinus (67%). A total of 66% of the patients had other SN associated infectious complications. ICU mortality was 5% and hospital mortality was 33%.

CONCLUSIONS

NS incidence in this study was low, but the risk of infectious complications was high.

Transnasal puncture based on echographic sinusitis evidence in mechanically ventilated patients with suspicion of nosocomial maxillary sinusitis

OBJECTIVE

The aim of this prospective study was to evaluate the value of sinus echography results to directly indicate a transnasal puncture in intubated patients with suspicion of nosocomial maxillary sinusitis.

DESIGN

prospective clinical investigation.

SETTING

medical intensive care unit.

PATIENTS

sixty patients undergoing intubation and mechanical ventilation more than 2 days, with a clinical suspicion of maxillary sinusitis with purulent nasal discharge.

INTERVENTIONS

120 sinuses were examined by sinus ultrasound. The image defined as normal was an acoustic shadow arising from the front wall. Two levels of positive echography were described: (1) a partial sinusogram was defined as the visualization of the hyperechogenic posterior wall of the sinus; and (2) a complete sinusogram was defined as the hyperechogenic visualization of posterior wall and the extension by the internal and external walls of the sinus. When sinus ultrasound was positive, a transnasal puncture was performed the same day. The transnasal puncture was positive if a fluid was obtained from sinus aspiration. The transnasal puncture was negative if there was no aspirated material.

MEASUREMENTS AND RESULTS

sinus ultrasound was positive in 84 cases (54 complete sinusograms and 30 partial sinusograms). Seventy-eight of 84 transnasal punctures were positive. Sensitivity of a sinusogram for obtaining positive transnasal puncture was 100%, and specificity was 86% (100% in case of complete sinusogram) in a clinically selected population. The only six negative transnasal punctures were performed in patients with partial sinusogram.

CONCLUSIONS

Ultrasound sinusitis evidence seems to be of value to indicate and perform a transnasal puncture directly, avoiding CT exam.

Sonography as an alternative to radiography for nasogastric feeding tube location

OBJECTIVE

To evaluate bedside sonographic confirmation of weighted-tip nasogastric feeding tube position, by comparison to radiography.

DESIGN AND SETTING

Single-center, double-blind prospective study in a 14-bed medical intensive care unit (ICU) in a 780-bed teaching hospital.

PATIENTS

Thirty-three ICU patients undergoing nasogastric tube insertion for enteral feeding.

INTERVENTIONS

The tip of the nasogastric tube was located both by sonography and standard radiography.

MEASUREMENTS AND RESULTS

The accuracy and procedure times of sonography and radiography for nasogastric tube tip location were compared during 35 procedures in 33 patients. The nasogastric tube tip was visualized by sonography in 34 of 35 procedures (sensitivity 97%) and by radiography in all procedures. The median length of the entire procedure was 24 min and 180 min with sonography and radiography, respectively.

CONCLUSIONS

Bedside sonography performed by nonradiologists is a sensitive method for confirming the position of weighted-tip feeding nasogastric feeding tubes. It is more rapid than conventional radiography and can easily be taught to ICU physicians. Conventional radiography could be reserved for cases in which sonography is inconclusive.

Hospital-acquired sinusitis is a common cause of fever of unknown origin in orotracheally intubated critically ill patients

Introduction

Sinusitis is a well recognised but insufficiently understood complication of critical illness. It has been linked to nasotracheal intubation, but its occurrence after orotracheal intubation is less clear. We studied the incidence of sinusitis in patients with fever of unknown origin (FUO) in our intensive care unit with the aim of establishing a protocol that would be applicable in everyday clinical practice.

Methods

Sinus X-rays (SXRs) were performed in all patients with fever for which an initial screening (physical examination, microbiological cultures and chest X-ray) revealed no obvious cause. All patients were followed with a predefined protocol, including antral drainage in all patients with abnormal or equivocal results on their SXR.

Results

Initial screening revealed probable causes of fever in 153 of 351 patients (43.6%). SXRs were taken in the other 198 patients (56.4%); 129 had obvious or equivocal abnormalities. Sinus drainage revealed purulent material and positive cultures (predominantly Pseudomonas and Klebsiella species) in 84 patients. Final diagnosis for the cause of fever in all 351 patients based on X-ray results, microbiological cultures, and clinical response to sinus drainage indicated sinusitis as the sole cause of fever in 57 (16.2%) and as contributing factor in 48 (13.8%) patients with FUO. This will underestimate the actual incidence because SXR and drainage were not performed in all patients.

Conclusion

Physicians treating critically ill patients should be aware of the high risk of sinusitis and take appropriate preventive measures, including the removal of nasogastric tubes in patients requiring long-term mechanical ventilation. Routine investigation of FUO should include computed tomography scan, SXR or sinus ultrasonography, and drainage should be performed if any abnormalities are found.

Surgeon-performed ultrasound in the ICU setting

Evaluation of critically ill patients is often challenging due to altered sensorium, underlying disease, and the presence of multiple drains or monitoring devices. In such circumstances, the ability of physicians to perform ultrasound examinations in the intensive care unit provides a useful diagnostic and therapeutic adjunct. In this article,we review the application of surgeon-performed ultrasonography in the evaluation and management of critically ill patients.

Sinusitis and fever of unknown origin

It is relatively uncommon to document sinusitis as a cause of fever with much certainty. Therefore, investigation for sinusitis should be undertaken only after more likely causes have been excluded. and the actions taken should reflect the individual patient's circumstances. Aggressive evaluation and treatment should be geared to minimizing the patient's overall morbidity and to identifying the more aggressive forms of sinusitis and their potential complications.

Comparison of ultrasonography, radiography and a single computed tomography slice for the identification of fluid within the canine tympanic bulla

Fluid accumulation within the tympanic bulla (TB) is an important diagnostic indicator in clinical cases of canine otitis media although its identification can be a challenge using currently available imaging techniques. The aim of this study was to compare ultrasound with radiography and a single computed tomography (CT) slice for the identification of fluid within the TB of canine cadavers. A random number of TB in 66 cadavers were filled with ultrasound gel. Rostrocaudal open mouth (RCdoM) radiographs and CT images were interpreted by 2 blinded radiologists and ultrasound examinations were performed by 2 blinded sonographers. The heads were then frozen and sectioned to confirm the contents of each TB. Although CT remained the most accurate method, comparable results were obtained by one of the sonographers and even the inexperienced sonographer produced results superior to radiography. Ultrasound has several advantages over the other imaging techniques and this study suggests that it may have an application in the investigation of canine otitis media although further work in live animals would be required to confirm this.

A rational approach to the evaluation and treatment of the infected patient in the intensive care unit

Critically ill patients are at increased risk of acquiring nosocomial infections. A thorough clinical evaluation and the selection of appropriate diagnostic techniques are important elements in the evaluation of these patients. Nonetheless, this selection process can be difficult because of the wide spectrum of disease that is seen in the ICU and the lack of standardized studies that have evaluated the different diagnostic methods that are available. Many different antimicrobials are available for the treatment of ICU-acquired infections. Most antimicrobial regimens have not been evaluated in large-scale, prospective, randomized trials. Until this information is available, the clinician must make an effort to be familiar with the different clinical and epidemiologic variables that can be used to stratify patients at the moment of selecting antimicrobial therapy. The information provided in this article, used in association with good clinical judgment, will help the critical care physician provide optimal initial management of the infected patient in the ICU.

Ultrasound imaging of the canine tympanic bulla

A procedure for imaging the canine tympanic bulla, external ear canal and adjacent structures using currently available ultrasound equipment was established. Lateral and ventral transducer positions were identified for this purpose and a 6.5 MHz curvilinear transducer was considered to be optimal. The sonographic appearance of these structures in cadavers and live dogs unaffected by ear disease is documented. Fluid was introduced into the tympanic bullae of the cadavers and its presence could be identified through the bony wall of the bulla. The ability of ultrasound to differentiate between gas and fluid within the bulla has important clinical implications as this is a common occurrence in dogs with middle ear disease. Ultrasound has several advantages over other imaging modalities and the examination procedure was well tolerated by unsedated dogs.

Long-term complications of artificial airways

In summary, long-term complications of artificial airways are rare but important sequelae of artificial airways. Many of the potential long-term complications of translaryngeal intubation and tracheotomy are similar and overlapping. Although most patients who undergo these procedures tend to tolerate them without difficulties, significant morbidity and mortality may occur. Identifying the exact cause of the complication may not be possible at times, due to the multiple risk factors involved in the pathogenesis. It is hoped that understanding these potential complications will lead to a more vigilant preventive measures during the institution of long-term artificial airways and a judicious early search for the underlying pathology when a complication is suspected.

Nosocomial pneumonia: emerging concepts in diagnosis, management, and prophylaxis

Nosocomial pneumonia is a dynamic disease with multiple etiologic agents and a changing natural history. The highest attack rates and mortality occur in patients with ventilator-associated pneumonia. Diagnosis of nosocomial pneumonia is often made by clinical criteria that are sensitive but lack specificity. The use of quantitative endotracheal aspirates or bronchoscopy with bronchoalveolar lavage and protected specimen brush clearly improve diagnostic specificity and outcome in patients who are mechanically ventilated. The rapid spread of multidrug-resistant, spp, and has made initial empiric therapy more difficult. Management principles include the use of techniques for more accurate diagnosis and early antimicrobial therapy with appropriate agents along with careful analysis of culture results, clinical response, and potential complications of pneumonia and therapy. Strategies for prophylaxis are of critical importance for risk reduction, improvement in patient outcome, and reduction of hospital costs.