Background: The stress response is a part of the systemic reaction to injury, which encompasses a wide range of endocrinological, metabolic, immunological and hematological effects. The stress response to surgery may be modified by anesthetic intervention. This study was designed to determine the effects imposed by the type of anesthesia, used during cataract surgery, on patients' stress response to surgery. Methods: This prospective study comprised 40 patients assigned to undergo cataract surgery. There were 20 non-diabetic patients (group I), and 20 controlled non-insulin diabetes mellitus (NIDDM) patients (group IT), 20 patients were anesthetized using prebulbar local infiltration anesthesia (LA) (group la & ITa), and the other 20 patients received general anesthesia (GA) (group Ib & IIb). Three venous blood samples, preoperative, intraoperative (1.0.) and 2 hours postoperatively (P.O.), were taken and divided into two parts. The first part was put in tube containing sodium fluoride and anticoagulant for estimation of blood glucose (BG), pyruvate, and lactate. The second part was left to clot, centrifuged, and supernatant was separated for estimation of serum urea, creatinine, cortisol, and C-peptide levels. Results: Preoperative serum cortisol (S. cortisol) in group lIb showed a significant increase compared to its level in both Ia and IIa groups. Also, LO. and P.O. serum cortisol showed a significant increase in group lIb compared to both group Ia and IIa. Furthermore, LO. and P.O serum cortisol showed a significant increase in groups Ib and IIb, but showed a nonsignificant increase in patients received LA. Preoperative BG showed a significant increase in group IIb compared to Ib and IIa groups. Intraoperative BG levels showed a significant increase in Ib and lIb groups compared to groups Ia and IIa, and in diabetics received GA versus their controls. Postoperative BG increased significantly in all diabetic patients compared to their preoperative values. Postoperative BG values were increased significantly in group I versus group II, and in group IIa versus group Ia and lIb. There was a positive significant correlation between S. cortisol and 1.0. and P.O. levels of BG levels in patients received GA both in control (r=0.67 I , P=0.033 & r=0.712, P=0.021, respectively) and diabetic, (r=0.731, P=0.016 & r=0.754, P=0.012, respectively) groups. Preoperative blood levels of pyruvate and lactate showed a significant increase in group II versus group I but non-significantly increased in lIb versus IIa. On the other hand, 1.0. and P.O. blood pyruvate and lactate showed a non-significant increase-in group II compared to group I, but .Showed a non-significant difference among diabetics. Furthermore, there was a significant decrease of 1.0. and P.O. blood pyruvate and non-significant decrease in blood lactate as compared to their preoperative values. Serum C-peptide revealed a non-significant difference between the three samples derived from patients received GA, while, there was a significant increase of P.O. serum C-peptide in IIa group compared both to group Ia and lib. Conclusion: We can conclude that serum cortisol and glucose response to cataract surgery was exaggerated by the use of general anesthesia, especially in diabetic patients, and on contrary abolished by the use of local anesthesia. |
