Central venous oxygen saturation monitoring in the critically ill patient.

In the initial treatment of a critically ill patient, blood pressure, heart rate, urine output, and central venous pressure guide resuscitative efforts. Despite normalization of these variables, global tissue hypoxia may still persist and has been implicated in the development of multiorgan failure and increased mortality. Definitive management includes intensive care unit admission, pulmonary artery catheterization using mixed venous oxygen saturation (SvO2), and hemodynamic optimization. In the absence of or before definitive management, hemodynamic optimization can be performed using central venous oxygen saturation (ScvO2) as a surrogate. The physiology, technology, clinical uses, and rationale for ScvO2 monitoring are reviewed, including issues regarding physiologic equivalence to SvO2. The clinical use of ScvO2 monitoring, evidence-based outcome implications, and limitations of ScvO2 monitoring will also be examined.

Undetected cardiogenic shock in patients with congestive heart failure presenting to the emergency department.

The purpose of this study was to examine the use of lactic acid levels and continuous central venous oxygen saturation (central venous oximetry) to stratify and treat patients with acutely decompensated end-stage chronic congestive heart failure (CHF) presenting to the emergency department. This prospective, convenience, non-outcome study was performed at an urban tertiary care hospital. Patients with end-stage CHF with an ejection fraction <30% presenting in decompensated CHF were eligible for the study. Patients were assessed using the Killip classification and New York Heart Association criteria. After lactic acid levels were obtained, patients were managed according to a standardized protocol guided by central venous oximetry. The patients were divided into high lactic acid (n = 22), low lactic acid (n = 5), and control groups (stable patients presenting to a cardiology clinic, n = 17) for comparison. There was no statistical difference in vital signs, or Killip and New York Heart Association criteria among the 3 groups. Central venous oxygen saturation was significantly lower in the high lactic acid group (32 +/- 12%) than in the normal lactic acid (51 +/- 13%) and control groups (60 +/- 6%) (p < 0.001). After treatment there was a significant decrease in lactic acid (-3.65 +/- 3.65 mM/L) and an increase in central venous oxygen saturation (32 +/- 13%) in the high lactic acid group compared with the normal lactic acid group (p < 0.001). A significant subset of patients with decompensated end-stage CHF present to the emergency department in occult shock and are clinically indistinguishable from patients with mildly decompensated CHF and stable CHF. Once identified, these patients require aggressive alternative management and disposition. Further study is necessary to identify whether this intervention impacts morbidity, mortality, and health care resource consumption.

Pseudo-Meigs' Syndrome.

Meigs' syndrome is defined as a hydrothorax with ascites and a pelvic tumor, both of which resolve on removal of the tumor. Pseudo-Meigs' is a variant not possessing the original tumor cell types described by Meigs. Both these syndromes should be considered in otherwise healthy women who present with either new or recurrent hydrothorax and ascites. This case concerns a 21-year-old woman who presented to the emergency department (ED) with a recurrent hydrothorax. After performing a pelvic examination that was suspicious for a pelvic mass, further evaluation by ultrasonography showed ascites and a pelvic tumor. Surgeons from the Obstetrics and Gynecology Department performed an exploratory laparotomy with removal of the tumor. Subsequently, there was no recurrence of the ascites and hydrothorax. The tumor was diagnosed histologically as a benign mature teratoma. The literature of Meigs' and Pseudo-Meigs' is reviewed, focusing on the history, pathology, and clinical characteristics. The clinical significance for the emergency physician is discussed.

Diagnostic evaluation for infectious etiology of sickle cell pain crisis.

Occult infections during sickle cell pain crisis can be associated with significant morbidity. It has been suggested that empiric workup for pneumonia and urinary tract infection (UTI) is required. A study was undertaken to determine whether clinical criteria can be used to exclude such infections as precipitants of pain crisis in adults. This retrospective, observational clinical study was conducted in an inner-city teaching hospital emergency department (ED) with 95,000 visits/year. Patients 18 years of age or older presenting to the ED with sickle cell pain crisis who had not used antipyretics within 6 hours before presentation were eligible. Ninety-four visits were evaluated. During initial evaluation the treating physician completed a questionnaire addressing systemic, pulmonary, and urinary tract signs and symptoms. Temperature and physical examination were recorded on an ED memo. Treatment modalities were at the discretion of the treating physician. All patients had a complete blood count, reticulocyte count, urinalysis, and chest radiograph. If the urinalysis was positive (>2 white blood cells) or the patient had clinical evidence of a UTI, a urine culture was obtained. UTI was confirmed through a urine culture with >100,000 colony-forming units/mL. Chest X-rays were reviewed by a staff radiologist. Definitive diagnosis of pneumonia was made by the presence of an infiltrate and a positive clinical response to antibiotic therapy. Thirty-eight patients totalling 94 visits to the ED were studied during an 18-month period. Six diagnoses of pneumonia and 3 diagnoses of UTI were made. All six patients with pneumonia had at least 4 of the signs and symptoms including fever, chills, cough, shortness of breath, sputum production, chest pain, hemoptysis, abnormal pulmonary examination, and temperature of >37.8 degrees C. Of the three patients with UTI, two had signs and symptoms inconsistent with UTI (asymptomatic bacteriuria). In patients with sickle cell pain crisis, medical history and physical examination can be useful to predict the absence of pneumonia, but may not be as beneficial in predicting the absence of UTI. These results suggest that empiric chest x-ray may be unnecessary to exclude pneumonia; however, routine urinalysis may be indicated. Because of the low incidence of these infections, larger studies are required to confirm these findings.

Medical management of ectopic pregnancy--the role of methotrexate.

Ectopic pregnancy is an increasing health risk for women throughout the world. Recent advances in measurements of serum quantitative beta human chorionic gonadotropin and transvaginal ultrasonography have made it possible to diagnose ectopic pregnancy without laparoscopy. These developments have provided the atmosphere for trials using methotrexate as a nonsurgical treatment for ectopic pregnancy. This article briefly reviews the epidemiology and diagnosis of ectopic pregnancy. The medical management of ectopic pregnancy with methotrexate is then reviewed in more detail.

Creatinine analysis in single collection urine specimens.

Controlled and uncontrolled fluid intake studies were conducted on series of volunteers over the 6 or 12 h of the study periods. Urine specimens were obtained from each subject randomly or at specified times relative to fluid ingestion. Creatinine analysis performed by a modification of the Abbott TDx procedure demonstrates that the values obtained from single collection specimens fall almost in the same range as the values from 24 h pooled collection specimens. The creatinine concentration can be used to indicate possible adulteration of urine specimens by dilution as a means of avoiding detection of use of drugs of abuse. Between 4 and 7 h are required for a decrease in creatinine concentration to about 100 mg/dL from an initial mean of about 170 mg/dL. A minimum of 6 h is needed for any creatinine value to fall to 50 mg/dL or less. Thus, it appears that creatinine output is sensitive to the amount of fluid ingested, but the relationship is neither linear nor immediate. The absence of a significant creatinine concentration in a specimen can be used as an indication of direct or indirect adulteration of the urine specimen by dilution or replacement with water. At NDSL-Great Lakes, a decline of the creatinine concentration to 30 mg/dL is used as a cutoff for differentiating between urine specimens that might have been tampered with to avoid detection of drug use and those specimens that are dilute for other reasons. Values at 10 mg/dL or less are suggestive of replacement by water. The information is provided to local commands for investigation prior to initiation of punitive action by the command.