Ultrasound guided L5-S1 placement of labor epidural does not improve dermatomal block in parturients.

BACKGROUND: Based on their experience or training, anesthesiologists typically use the iliac crest as a landmark to choose the L3-4 or L2-3 interspace for labor epidural catheter placement. There is no evidence-based recommendation to guide the exact placement. We hypothesized that lower placement of the catheter would lead to a higher incidence of S2 dermatomal block and improved analgesia in late labor and at delivery. METHODS: One-hundred parturients requesting epidural analgesia were randomly assigned to receive ultrasound-guided L5-S1 epidural catheter placement (experimental group) or non-ultrasound-guided higher lumbar interspace placement (control group). The primary outcome was the incidence of S2 block 30 minutes after administering 10 mL 0.125% bupivacaine. Secondary outcomes were average pain throughout labor and maximum pain during labor or during delivery. RESULTS: Forty-nine subjects were enrolled in control group and 47 in the experimental group. The primary endpoint did not significantly differ between groups (control group 81% vs experimental group 91%, P=0.24). The secondary endpoints were not significantly different: pain relief after 30 minutes (mean pain score 1.4 in the control group vs 1.9 in the experimental group, P=0.2) and pain at delivery (mean score 4 in the control group vs 3.9 in the experimental group, P=0.6). CONCLUSION: Placement of an epidural catheter at the L5-S1 interspace using ultrasound did not improve sacral sensory block coverage when compared with an epidural catheter placed at a higher lumbar interspace, without using ultrasound guidance.

Cardiac or pulmonary dyspnea in patients admitted to the emergency department.

A simple and quick way of discrimination between cardiac and pulmonary causes of dyspnea is essential in patients admitted to the emergency department. We aimed to assess the utility of easily applicable diagnostic tools in the differential diagnosis of cardiac and pulmonary causes of dyspnea in patients presenting with shortness of breath. Clinical and radiologic evaluation, peak expiratory flow (PEF), PaO2, PaCO2 measurements were performed in 94 patients admitted to the emergency room with dyspnea. All the patients were hospitalized for accurate diagnosis and later were categorized into cardiac and pulmonary dyspnea groups. PEF, %PEF (percent of predicted PEF), dyspnea differentiation index (DDI = PEF x PaO2/1000), %DDI (%PEF x PaO2/1000), PaO2 and PaCO2 measurements were compared between the two groups. When cardiac and pulmonary dyspnea groups were compared, considering 1.6 as the cut-off value for DDI, measurements above this value imply cardiac pathology with 76.7% sensitivity and 67.2% specificity. The sensitivity and specificity for cardiac dyspnea calculated according to the cut-off values were 96.7% and 40.6% for %DDI; 86.7% and 60.9% for PEF; 86.7% and 54.7% for %PEF; 66.7 and 68.7 for PaO2. Also for pulmonary dyspnea, sensitivity and specificity values for PaCO2 were 50% and 93%. We conclude that DDI, %DDI, PEF, %PEF, PaO2 and PaCO2 are simple and easily applicable tools for differential diagnosis of cardiac and pulmonary dyspnea. Adjunctive utility of these tests in the emergency department with clinical and radiologic evaluation contributes to this discrimination.