Cerebral blood flow velocity alterations, under two different carbon dioxide management strategies, during sevoflurane anesthesia in gynecological laparoscopic surgery

Abstract

In this study, 33 female patients, scheduled for operative gynecological laparoscopies, were enrolled. Our aim was prospective, randomized comparison of the influence of two different management strategies, regarding end tidal CO2, on cerebral blood flow velocities and on pulsatility index, examined by means of transcranial Doppler ultrasonography, under sevoflurane anesthesia 1.3 MAC: permissive hypercapnia (up to 45 mmHg, Group I, n = 17) versus intervention to ensure mild hypocapnia, (around 33 mmHg, Group II, n = 16). Baseline measurements of investigated parameters were recorded and CO2 insufflation started. In Group I no further adjustment was performed and CO2 partial pressure rose, while in Group II it was kept stable, by ventilatory patterns adjustment. Hemodynamic, acid base balance and cerebrovascular variables were recorded during pneumoperitoneum and in post-desufflation period, at eight checking time points. In Group I cerebral blood flow velocities increased according to CO2 elevation (2.3%-3.9% per mmHg of increase in CO2 partial pressure), whereas in Group II no significant alterations were noticed. Pulsatility index was constant over time without clinical differences between groups. Our study suggests that under sevoflurane anesthesia 1.3 MAC, prophylactic hyperventilation limits the cerebral blood flow velocities enhancing effect of CO2 insufflation, during laparoscopies.

The Effect of Gynaecological Laparoscopic Surgery on Cerebral Oxygenation

“…8 -10 When patients' arterial carbon dioxide levels are managed within the normocapnic range, the pneumoperitoneum does not cause any change in CBF. 24 In our study, the cerebral oxygenation level was maintained in patients whose PACO 2 was controlled within the normocapnic range. In contrast, in patients who failed to be 27 may have been related to increased ICP in association with hypercapnia.…”

Cerebral oximetry and laparoscopic surgery

“…By selecting the proper anaesthetic agent or by using specific surgical manoeuvres, possessing protective properties, regarding cerebrovascular dynamics can minimize the potential negative effects of pneumoperitoneum, hypercarbia and haemodynamic fluctuations on cerebrovascular balance. [3] Monitoring of rSO2 is a useful tool in clinical setting providing the ability to immediately detect alterations in cerebral perfusion, thereby giving the opportunity for early intervention. Due to the wide patient to patient variability of baseline rSO2 values, in each patient the baseline value should be determined before induction of anaesthesia as cerebral ischaemia is more related to the changes from baseline than to absolute values.…”

The relationship between the Trendelenburg position and cerebral hypoxia inpatients who have undergone robot-assisted hysterectomy and prostatectomy

“…was hypercapnic. As long as patients have normal PaCO 2 values, pneumoperitoneum does not cause changes in CBF and therefore normocapnia is important in terms of cerebral oxygenation(16,17). In our study, we kept the IAP between 12 and 15 mmHg since CO 2 pneumoperitoneum…”