Abstract :
Introduction: Use of Mayfield skull clamp during craniotomies; results in a sharp and intense noxious
stimulus which results in a severe hemodynamic pressor response. Many strategies have been reported to
blunt this undesirable pressor effect. This prospective, double blind, and randomized study is the first to
evaluate the effect of MgSo4 on attenuation of hemodynamic pressor activity after head clamp application
during craniotomies.
Materials and Methods: This randomized, double blind, and prospective study was done in Neurosurgical
department at ElSahel Teaching Hospital in Cairo from February 2016 till august 2017. All adult patients
aged from 18 to 60 years of both genders, ASA physical status I and II scheduled for craniotomies were
assessed to enter this study. Seventy one patients were assessed preoperatively, sixty of them were enrolled
and assigned in two groups (n =30 each). Group M received 50 mg/kg MgSo4 in 100 ml 0.9 sodium
Chloride 15 minutes prior to anesthesia induction over 15 minutes. Group S received 100ml 0.9% Sodium
Chloride over the same period with the same rate. MAP, HR and the need for a bolus dose of fentanyl were
recorded as primary outcomes.
Results: Mean HR just before pins insertion (pinpre ) was 74. 5.91/min in group M and 75.47 5.21/min
in group S without significance difference (p =0.312) while at insertion time (Pin0) it started to show
significance difference (p < 0> group S. After 30 minutes (pin 30), mean HR was 77.4 3.83 /min in group M and 79.23 5.19/min. in
group S with statistically insignificant value (p = 0.124). Mean MAP showed the same way of difference.
Conclusion: Hemodynamic pressor effect resulting from the application of Mayfield clamp during
craniotomies can be attenuated by the administration of a single dose MgSo4.
Keyword :
MgSo 4, Mayfield clamp, Pressor effect.