Case

A 31-year-old male presents to the ED with a chief complaint of RUQ abdominal pain. The pain started approximately 7 hours prior and continues to worsen. The pain is described as crampy, 6/10, and radiates to the back. The patient reports nausea, one episode of vomiting (non-billous and non-bloody), and anorexia. The patient denies CP, SOB, diarrhea, fever, or chills.

Initial vital signs of BP 122/67, HR 82, RR 14, Temp 96 degrees. On physical exam the patient is in moderate distress secondary to pain. Routine physical examination is significant for RUQ tenderness.

Discussion

Half a million cholecystectomies are performed and approximately 10,000 people die each year from gall bladder disease in the United States. Chief complaints vary from the classic right upper quadrant pain of biliary colic, to vague epigastric pain, right shoulder or flank pain, and occasionally sepsis without a source in the elderly and chronically ill. No single or combination of clinical or laboratory findings is sensitive enough to reliably exclude acute cholecystitis (1). Liberal use of diagnostic tools such as RUQ US are necessary to detect cases of acute cholecystitis before complications occur. Limited ED US allows the Emergency Physician to rapidly make accurate, more timely, and more cost effective patient care decisions.

Limited ED US findings indicative of acute cholecystitis include gallstones, sonographic Murphy’s sign, wall thickening, and pericholecystic fluid. 95% of patients with acute cholecystitis will have gallstones. Studies of limited ED US demonstrate a sensitivity of 92-96% and specificity of 78-88% for the detection of gallstones. A sonographic Murphy’s sign detected by the EP is 75% sensitive for the diagnosis of acute cholecystitis; 91% sensitive when combined with the presence of gallstones (2).

Gallbladder wall thickening is a secondary sign of acute cholecystitis occurring in other conditions such as congestive heart failure, ascites, kidney disease, hepatitis and normal contracted gall bladders. With symptoms of acute cholecystitis, the combination of gallstones and gallbladder wall thickening greater 3mm has a positive predictive value of greater then 90% for acute cholecystitis. Pericholecystic fluid, hypoechoic fluid surrounding or within the GB wall, is a rare but highly specific sign of acute gall bladder disease. A dilated common bile duct CBD greater than 6mm, or the decades in life divided by 10, typically results from ductal obstruction due to choledocholithiasis. However the exact cause of ductal obstruction is best determined by other studies such as abdominal CT (2).

From multiples studies the overall sensitivity and specificity for the diagnosis of acute cholecystitis by limited ED US is 90% and 66-85% respectively. In comparison the overall sensitivity and specificity of formal radiology ultrasound is 84-90% and 90-99%. As residency training increases and US technology improves, the accuracy of limited ED US for acute cholecystitis will continue to improve (2).

The most significant advantage of Limited ED US for hepatobiliary disease is the ability of the physician to rapidly rule out a diagnosis without the time delays of formal radiology studies. Smaller institutions often do not have 24-hour ultrasonography available. After hours the sonographer must be called in from home to perform the exam. Then the radiologist must read the images resulting in significant time delays. Multiple studies demonstrate that limited ED US is accurate while decreasing the length of stay and cost of ED care (3). Over time the cost of purchasing an US system will likely be less then calling in the US tech.

Limited ED US improves patient care within our busy ED at Cook County Hospital. ACEP US credentialed emergency medicine attendings and residents perform limited ED US of the Gall bladder and CBD on patients presenting with symptoms of biliary disease as part of the physical examination. If no gallstones, Sonographic Murphy’s sign, gallbladder wall thickening, pericholecystic fluid or common bile duct dilatation is present, biliary disease is excluded. Likewise, when only gallstones are present without a Sonographic Murphy’s sign or secondary signs of acute cholecystitis, acute cholecystitis is excluded. Renal US then is frequently performed since both renal and biliary stone present often present with similar complaints. When gallstones are present with a Sonographic Murphy’s sign or secondary signs of acute cholecystitis, surgical consultants are called and additional formal radiology US or abdominal CT scan is often performed.

Conclusion

The ultrasound examination was performed and the appropriate consultant notified within 20 minutes of the patient being seen by the physician. General surgery interviewed and examined the patient, reviewed the Limited ED US images, and admitted the patient with a diagnosis of acute cholecystitis for IV antibiotics and cholecystectomy even before labs were back. 2 hours were saved using ED ultrasound instead of sending the patient for a formal radiology US.

The emergency department is a unique environment where diagnostic information must be obtained with speed and accuracy. New ultrasound technology continues to make US images easier to obtain and interpret in the fast paced world of the ED.

References

1. Singer AJ, McCracken G, Henry MC, Thode HC, Jr., Cabahug CJ. Correlation among clinical, laboratory, and hepatobiliary scanning findings in patients with suspected acute cholecystitis. Ann Emerg Med 1996; 28(3):267-272.
2. Shah K, Wolfe RE. Hepatobiliary ultrasound. Emerg Med Clin North Am 2004; 22(3):661-73, viii.
3. Blaivas M, Harwood RA, Lambert MJ. Decreasing length of stay with emergency ultrasound examination of the gallbladder. Acad Emerg Med 1999; 6(10):1020-1023.