Intracranial nonjugular venous pathways: a possible compensatory drainage mechanism

BACKGROUND AND PURPOSE

The IJVs are considered to be the main pathway draining the intracranial venous system. There is increasing evidence for the existence of alternative venous pathways. Studies using extracranial sonography techniques have demonstrated a nonjugular venous system. In the current study, we used MR images to investigate the NJV drainage system and its components (vertebral plexus, pterygopalatine plexus). The exact visualization and measurement of the intracranial NJVs could be of diagnostic importance and may have clinical importance.

MATERIALS AND METHODS

A total of 64 participants with no history of neurologic disease were included in the study. All participants underwent scanning with a 2D time-of-flight, multisection sequence in the supine position. Image processing software was developed to identify and quantify the size of the IJVs and NJVs in the plane of the internal JF. For evaluation of software accuracy, all images were reviewed by a neuroradiologist experienced in neurovascular imaging preprocessing and postprocessing.

RESULTS

The CSA of the NJVs correlated inversely with the CSA of the IJVs (r(2) = 0.25; P < .0001). An inverse correlation was also significant when comparing IJV with NJV components (vertebral plexus: r(2) = 0.19; P = .0004; pterygopalatine plexus: r(2) = 0.11; P = .0069). Furthermore, only NJV cumulative CSA correlated inversely with participant age (r(2) = 0.2; P = .0002).

CONCLUSIONS

Our study indicates that the NJVs might serve as a compensatory drainage mechanism in the intracranial compartment. This mechanism appears less significant as the age of the patient progresses.

Adverse effects of epidural analgesia in labor

OBJECTIVE

To examine the influence of epidural analgesia on labor and delivery in nulliparous and multiparous women.

DESIGN

Data were collected on 847 consecutive parturients with singleton pregnancy and vertex presentation (384 nulliparous and 463 multiparous). The obstetrical and labor characteristics including maternal age, parity, gestational age, previous cesarean section, instrumental delivery, mode and timing of analgesia, mode of delivery, indications for cesarean section or instrumental delivery were analyzed comparing patients who received epidural analgesia with women who received systemic analgesia.

RESULTS

Epidural analgesia was administered in 233 nulliparous and 141 multiparous women. A stepwise logistic regression analysis revealed that epidural analgesia independently affected the rate of non-spontaneous delivery and the duration of the second stage of labor in nulliparous (P=0.0017 and P=0.0036, respectively) and multiparous (P=0.001 and P=0.0081, respectively) women. Epidural analgesia independently affected the duration of labor only in nulliparous women (P=0.0001).

CONCLUSION

Women should be informed that prolongation of labor and increase in nonspontaneous deliveries should be expected when choosing epidural analgesia in labor.

Maternal and newborn levels of glucose, sodium and osmolality after preloading with three intravenous solutions during elective cesarean sections

The influence of maternal i.v. loading with 1500 ml fluid prior to epidural anesthesia and elective cesarean section was studied in 60 healthy parturients near term. Three different solutions were used. Normal saline 0.9%, Hartmann's solution and dextrose 5%. A significant rise in glucose level accompanied by a significant decrease in sodium level was found in mothers and newborns of the group hydrated with the dextrose solution.