Csilla Molnár

Postcraniotomy headache (PCH) is a frequent perioperative complication in neuroanesthesia. The aim of the present work was to assess the incidence of PCH and to test the efficacy and safety of preoperatively administered diclofenac. Patients undergoing craniotomies for intracranial tumor resections were enrolled. In the case group 100 mg diclofenac p.o. one hour prior to surgery was used as a preemptive analgesic along with infiltration of the surgical site with a combination of lidocaine and epinephrine. In controls only surgical site infiltration was used. VAS scores were assessed preoperatively, on the day of surgery (DoS), on the 1st and 5th postoperative days. We have found that PCH of any severity is between 50-90% during the first five days after surgery. The number of cases characterized as "no pain" significantly decreased in the early postoperative period, but remained in both groups still higher on the 5th postoperative day than observed preoperatively. In both groups, the number of headaches characterized as mild pain remained relatively stable and substantial increases in case numbers were observed in moderate and severe headaches, showing a declining tendency over time in the postoperative period. A significant effect of diclofenac pretreatment was observed compared to controls on DoS (chi2: 10.429, p<0.015), on the 1st (chi2: 8.75, p<0.032) and 5th postoperative days (chi2: 14.3, p<0.002). The relatively low incidence of severe PCH on day five in the diclofenac group may indicate that preoperatively administered diclofenac effectively reduces postcraniotomy headache. A randomized study is encouraged to test this hypothesis.

The role of transcranial Doppler sonography in diagnosis of brain death (a practical review). The authors summarize the most important technical and practical knowledge regarding transcranial Doppler sonography. The characteristic Doppler signs of the cessation of cerebral blood flow are demonstrated, such as: oscillating flow, systolic spikes and zero-flow. The relatively high sensitivity (93.3%) of the repeated transcranial Doppler measurements in brain death diagnosis is highlighted.

Adolescent hypertension predicts hypertension and increased cardiovascular morbidity in adulthood. The aim of the present work was to test whether cerebrovascular reactivity to CO2 is altered among hypertensive adolescents. From the population-based cohort of the Debrecen Hypertension Study, 113 hypertensive and 58 normotensive adolescents underwent transcranial Doppler measurements at rest and after 30 seconds of breath holding. Systolic, mean, and diastolic blood flow velocities were higher among hypertensive individuals at rest. Taking the absolute blood flow velocity parameters into account, after breath holding, only the pulsatility index was significantly higher in the hypertensive group. The percentage change of the different blood flow parameters showed less intensive change in hypertensive teenagers. Cerebral vasoreactivity is decreased among hypertensive individuals as compared to healthy controls.

The aim of the present study was to assess the time course of hyperventilation (HV) and breath-holding (BH) tests in healthy volunteers. Young healthy volunteers (n = 29) underwent continuous registration of the middle cerebral artery mean blood flow velocity (MCAV) during and after 30 seconds of BH and 60 seconds of HV. Absolute values as well as percentage changes of the MCAV are reported. In 13 subjects, determination of capillary blood gas parameters (pH, pCO2, pO2, and O2 saturation) was performed before tests, after BH and after HV. MCAV during 30 seconds of breath-holding starts to increase after 10 seconds and reaches its highest level at 30 seconds. After breathing normally, MCAV normalizes within 30 seconds. Hyper-ventilation results in a decrease in MCAV, which reaches a plateau at 20 to 30 seconds after starting to hyperventilate, and blood flow velocity did not change significantly any further until the end of the procedure. The normalization of the MCAV is incomplete at 30 seconds after finishing hyperventilation. None of the capillary blood gases changed significantly after breath-holding, whereas capillary pH, pO2, and oxygen saturation increased and pCO2 decreased after hyperventilation. No relationship was found between capillary blood gas parameters and MCAV values. The authors concluded that breath-holding and hyperventilation tests seem to be a practical alternative to acetazolamide and the CO2 inhalation method in the assessment of cerebral hemodynamics.

To compare cerebral autoregulatory responses obtained during roll over tests in healthy pregnant women and those with pre-eclampsia in order to assess the middle cerebral artery velocity changes in relation to the roll over test in normotensive and pre-eclamptic women. Twenty-two healthy pregnant women and 26 with pre-eclampsia underwent transcranial Doppler measurements of the middle cerebral artery. Systolic, mean and diastolic blood flow velocities and mean arterial blood pressures were recorded in the left lateral position and five minutes after turning to the supine position. Absolute values of mean blood flow velocities, mean arterial blood pressure values and calculated cerebral blood flow indices as well as cerebrovascular resistance area products were compared at different positions among the groups. Mean arterial blood pressure increased in both groups while turning from the left lateral to the supine position. In women with pre-eclampsia both mean arterial blood pressure and absolute values of mean blood flow velocity values were higher in both positions, compared with healthy pregnant women. In both groups, changing the position resulted in a decrease of absolute values of mean blood flow velocities. Calculated cerebral blood flow indices did not change, while cerebrovascular resistance area products increased significantly in the groups during roll over testing. In women with pre-eclampsia, the increase of cerebrovascular resistance area products was more pronounced as compared with healthy pregnant women. In women with pre-eclampsia roll over test results in an increase of the mean arterial blood pressure, which is accompanied by a decreased mean blood flow velocity in the middle cerebral artery. Further studies are needed to clarify the pathophysiological background of cerebral haemodynamic changes in pre-eclampsia.