Bedside ultrasound in decision making for emergency surgery: its role in medical intensive care patients

Comparability of size measurements of the pancreas in magnetic resonance imaging and transabdominal ultrasound

INTRODUCTION

Transabdominal ultrasound (US) and magnetic resonance imaging (MRI) are commonly used for the examination of the pancreas in clinical routine. We therefore were interested in the concordance of these two imaging methods for the size measurement of the pancreas and how age, gender, and body mass index (BMI) affect the organ size.

METHODS

A total of 342 participants from the Study of Health in Pomerania underwent whole-body MRI and transabdominal US on the same day, and the diameter of the pancreatic head, body, and tail were measured. The agreement between US and MRI measurements was assessed by Bland and Altman plots. Intraclass correlation coefficients were used to compare observers. A multivariable regression model was applied using the independent variables age, gender, and body mass index.

RESULTS

Compared to MRI, abdominal US returned smaller values for each segment of the pancreas, with a high level of inconsistency between these two methods. The mean difference was 0.39, 0.18, and 0.54 cm for the head, body, and tail, respectively. A high interobserver variability was detected for US. Multivariable analysis showed that pancreatic size in all three segments increased with BMI in both genders whereas pancreatic head and tail size decreased with age, an effect more marked in women.

CONCLUSIONS

Agreement of pancreatic size measurements is poor between US and MRI. These limitations should be considered when evaluating morphologic features for pathologic conditions or setting limits of normal size. Adjustments for BMI, gender, and age may also be warranted.

Is the Pocket Ultrasound the “Phonendoscope” of the Urologist?

The objective was to evaluate the utility of the “pocket ultrasound” in making clinical decisions in urologic emergencies. From May to September 2011, 105 patients were assessed for urologic emergencies: acute flank pain, macroscopic hematuria, urinary retention, and lower urinary tract symptoms. All patients underwent an ultrasonographic examination whereby the pocket ultrasound was used to evaluate the kidneys and bladder, followed by another appropriate diagnostic test to verify the suggested diagnosis. Urinary retention was diagnosed in 10 patients. Of 48 subjects with hematuria, 34 had an immediate diagnosis: there were 18 cases of a bladder tumor, 13 cases of urolithiasis, and 2 cases of renal cell carcinoma; one ureteral stent was detected. Of 30 patients referred with lower urinary tract symptoms, 14 showed a high post micturition residual and 2 were seen to have bladder diverticula. Of 17 patients with acute flank pain, 1 had a kidney abscess, 5 had hydronephrosis, and 11 had urolithiasis. Ultrasonography provided a conclusive diagnosis in 67.6% of cases. Point-of-care pocket ultrasound allows a rapid diagnosis for treatment or triage of patients for appropriate referral to other diagnostic methods.

Acute abdomen in the medical intensive care unit

OBJECTIVE

Acute abdominal complication in the medical intensive care unit may be underdiagnosed and can add significant risk of death. We hypothesize that delays in surgery because of atypical presentation, such as the absence of peritoneal signs, may contribute to mortality.

DESIGN

Retrospective cohort study (1995-2000).

SETTING

Medical intensive care unit in a tertiary care center.

PATIENTS

Medical intensive care unit patients with clinical, surgical, or autopsy diagnosis of acute abdominal catastrophe (gangrenous or perforated viscus).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Seventy-seven patients (1.3%) met inclusion criteria. Ischemic bowel was the most common diagnosis, followed by perforated ulcer, bowel obstruction, and cholecystitis. Actual mortality rate was higher than predicted by Acute Physiology and Chronic Health Evaluation (APACHE) III scores at the time of medical intensive care unit admission (63% vs. 31%). Twenty-six patients (34%) did not have surgery, and none of these survived. Fifty-one patients underwent surgery and 28 survived (56%). Delay in surgical evaluation (p <.01) and intervention (p <.03), APACHE III scores (p <.01), renal insufficiency (p <.01), and a diagnosis of ischemic bowel (p <.01) were associated with increased mortality rates. Surgical delay was more likely to occur in patients with altered mental state (p <.01), no peritoneal signs (p <.01), previous opioids (p <.03), antibiotics (p <.02), and mechanical ventilation (p <.02).

CONCLUSION

Delays in surgical evaluation and intervention are critical contributors to mortality rate in patients who develop acute abdominal complications in a medical intensive care unit.

Surgeon-performed ultrasound imaging in acute surgical disorders

As the role of the general surgeon continues to evolve, the surgeon's use of ultrasound imaging will surely influence practice patterns, particularly for the evaluation of patients in the acute setting. With the use of real-time imaging, the surgeon receives "instantaneous" information to augment the physical examination, to narrow the differential diagnosis, or to initiate an intervention. With select ultrasound examinations, the surgeon can rapidly evaluate adult and pediatric patients with an acute abdomen, especially those patients who are hypotensive. In the hands of the surgeon, this noninvasive, bedside tool can assess more accurately the presence, depth, and extent of an abscess, confirm complete aspiration, or diagnose wound dehiscence before it is apparent on physical examination. Ultrasound imaging is so accurate for the diagnosis of pyloric stenosis that it has essentially replaced the upper gastrointestinal series in most institutions. The surgeon's use of ultrasound imaging to detect a pleural effusion has virtually supplanted the lateral decubitus radiograph. Furthermore, an ultrasound-guided thoracentesis not only facilitates the procedure but improves its safety. As surgeons become more facile with ultrasound imaging, it is anticipated that other uses will develop to further enhance its value for the assessment of patients in the acute setting.

Ultrasound and other imaging technologies in the intensive care unit

As technology advances, more imaging and procedures are performed at the bedside on critically ill patients in ICUs, thereby eliminating the risks of transporting patients. These imaging techniques can serve as diagnostic and therapeutic tools in treating the acute and chronic consequences of injured, critically ill patients. One area of growth is ultrasonography. Critical care applications of ultrasonography are expanding, and the learning curve of surgeons and intensivists performing some of these studies is improving. Ultrasonography can supplement physical examination and provide useful "real-time" information on nearly every body cavity. Other imaging technology is also available in a portable form, enabling imaging directly at the bedside. Images are now becoming readily and easily available with the advancement of teleradiology. Some of the imaging modalities are still in development, and their clinical effectiveness is being studied. In the future, more uses of these various imaging technologies may become evident and cost-effective.

Sonographic assessment of traumatic injury. Future developments

In all its forms and applications, sonography plays a significant role in the management of injured patients, from the emergency department to beyond hospital discharge. The use of new and existing sonographic technology will increase because sonographic imaging and measurements are generally less invasive; are inexpensive; use no ionizing radiation; and are portable, repeatable, and, in many instances, as accurate as the so-called "contemporary gold standards." The training and credentialing of physicians in sonography is in evolution and will be an increasingly important issue with more widespread use and broader applications. The future of sonography in trauma care in the next millennium is bright, and surgeons and surgical residents are encouraged to gain proficiency and learn about this new surgical frontier as it evolves.

The surgeon's use of ultrasound in the acute setting

As the role of the general surgeon continues to evolve, the surgeon's use of ultrasound will surely influence practice patterns, particularly for the evaluation of patients in the acute setting. With the use of real-time imaging, the surgeon receives "instantaneous" information to augment the physical examination, narrow the differential diagnosis, or initiate an intervention. With select ultrasound examinations, the surgeon can rapidly evaluate adult and pediatric patients who present with an acute abdomen, especially those in shock. In the hands of the surgeon, this noninvasive bedside tool can more accurately assess the presence, depth, and extent of an abscess, confirm complete aspiration, or diagnose wound dehiscence before it is apparent on physical examination. Ultrasound is so accurate for the diagnosis of pyloric stenosis that it has essentially replaced the upper gastrointestinal series in most institutions. The surgeon's use of ultrasound to detect a pleural effusion has virtually replaced the lateral decubitus film. Furthermore, an ultrasound-guided thoracentesis not only facilitates the procedure but improves its safety. Many ICUs now have protocols in place to perform routine duplex surveillance of those patients who are considered at high risk for the development of thromboembolic complications. As surgeons become more facile with ultrasound, it is anticipated that other uses will develop to further enhance its value for the assessment of patients in the acute setting.

Psoas abscess: making an early diagnosis in the ED

The variable and nonspecific presentations of psoas abscess, as well as its infrequent incidence in the emergency department (ED), can result in delayed diagnosis or misdiagnosis. Previous reports have not discussed the diagnostic difficulties of psoas abscess from the viewpoint of emergency physicians (EPs), especially in light of the widespread use of ED ultrasonography. This report describes a 1-year experience between November 1993 and October 1994, during which 10 ED patients were diagnosed to have psoas abscess; in 7 cases, diagnoses were established in the ED. Patients' mean age was 64.6 years (range, 46 to 76). Pain was the most frequently encountered symptom (80%), with 5 patients (50%) complaining of flank pain. The triad of fever, flank pain, and limitation of hip movement, which is specific for psoas abscess, was present only in 3 patients (30%). The mean duration of symptoms was 10.6 days (range, 1 to 30 days). The mean time spent to establish the diagnosis was 1.7 days (range, 0 to 7 days). The diagnosis of psoas abscess was established by ultrasound in 6 patients, by computed tomography (CT) in 3 patients, and by surgery in 1 patient. Four patients who presented with either sepsis and nonspecific abdominal/flank pain or sepsis and thigh swelling were diagnosed to have psoas abscess by ultrasound performed by EPs. Only 3 patients were admitted to the ED with an initial diagnosis of psoas abscess. The remaining 7 had the following initial ED diagnoses: 2, fever of unknown origin; 2, septic shock; 1, shock; 1, sepsis; and 1, peritonitis. All but one had manifestations of sepsis. Two patients died of septic shock; these two patients had failed to be drained well. This report also includes a discussion of the role of EPs and ultrasonography in the diagnosis of psoas abscess. With their alertness and their expertise in ultrasonographic techniques, EPs can make an immediate diagnosis and arrange an early drainage procedure. For patients with sepsis of unknown origin, prolonged fever of unknown origin, and some specific manifestations suggestive of psoas abscess, the screening ultrasound should scan not only abdominal solid organs but also peritoneal cavity and retroperitoneal space. In addition, a flow chart is presented for facilitating the diagnosis of psoas abscess in the ED.

Conventional radiography and ultrasonography in the diagnosis of small bowel obstruction and strangulation

Ninety-six patients, 45 men and 51 women (mean age 39 years, range 13- 90 years), with clinically acute abdomen were examined by conventional abdominal radiography and ultrasonography during a period of one year. Ultrasonography was performed with a linear transducer, which permitted study of morphology and motility of small bowel loops: distention, paralysis, intramural thickening, and extraluminal fluid. Nineteen cases of mechanical obstruction (9 simple and 10 of strangulation type) were observed. In the strangulation group ultrasonographic findings were positive in 91% whereas conventional radiography solely was positive in 30%. In the simple obstruction, 89% and 78%, respectively, were correctly diagnosed by the 2 techniques. Ultrasonography is recommended as a routine examination beside conventional abdominal films in acute abdomen.