COMPARATIVE STUDY OF INTRA OPERATIVE BLOOD SUGAR LEVEL IN SPINAL ANESTHESIA AND GENERAL ANESTHESIA IN PATIENTS UNDERGOING ELECTIVE SURGERY Affiliation

Bajracharya A, Sharma SM, Bawa SM, Rajbanshi LK, Arjyal B. Comparative Study of Intraoperative Blood Sugar Level In Spinal Anesthesia and General Anesthesia in Patients Undergoing Elective Surgery. BJHS 2018;3(2)6: 458-462. * Corresponding Author Dr. Akriti Bajracharya Lecturer Department of Anesthesia and Intensive Care Birat Medical College and Teaching Hospital Email: akriti854@gmail.com ORCID: https://orcid.org/0000-0001-5948-161X ORA 75 1* Bajracharya A , Sharma SM2, Bawa SN3, Rajbanshi LK1, Arjyal B1


ABSTRACT Introduc on
The aim of the study was to carry out the compara ve study of varia ons in blood glucose levels intra opera vely in pa ents undergoing surgical procedures in Spinal Anesthesia and General Anesthesia by capillary blood glucose level.

Objec ve
To compare intra opera ve blood glucose level in Spinal and General Anesthesia.

Methodology
Sixty non diabe c pa ents (30 in each group) aged between 20 -60 years belonging to ASA I and ASA II status were enrolled for this prospec ve compara ve study.Capillary blood glucose was measured preopera vely and there a er at 15 minutes interval a er incision in Spinal Anesthesia and a er induc on of General Anesthesia ll one hour of surgery.For sta s cal analysis paired sample t -test was used for comparing mean of quan ta ve data.Difference was considered sta s cally significant if p < 0.05.

Results
Blood sugar level was well controlled in pa ents receiving spinal anesthesia.General anesthesia produced more increase in blood sugar level compared to base line value which was sta s cally significant (P<0.05).Similarly, Glycaemia was significantly higher in the General anesthesia group (p < 0.05) when compared with Spinal Anesthesia group sugges ng poor control of stress response during general anesthesia.

INTRODUCTION
Periopera ve morbidity and mortality can be affected by [1][2][3] the inadequate glycemic control in the surgical pa ents.High blood glucose level has been associated with poor clinical outcomes in both diabe c and non diabe c surgical pa ents.Adequate periopera ve glycemic control is in fact 4 a challenge especially in diabe c pa ents.The evidences have shown that the mortality in pa ents with non cardiac 5 surgery was 24% at one year.Ischemic heart disease, urgent surgery, higher American Society of Anesthesiologists (ASA) physical status score and hyperglycemia were the major 5,6 predictors of increased periopera ve mortality.Periopera ve blood sugar control was the major component of anesthe c care that may need more stringent control but ght control of blood sugar level may also have nega ve outcomes as shown in the data from the Normoglycemia in Intensive Care Evalua on-Survival Using Glucose Algorithm 7 Regula on (NICE-SUGAR) study.Surgery is usually associated with increased stress response which is characterized by increased secre on of pituitary hormones and ac va on of the sympathe c nervous 8 system.Ac va on of sympathe c nervous system increases the secre on of adrenal medulla.Central nervous system response to stress is hypophyseal pituitary axis ac va on and increase in adrenocor cotrophic hormone (ACTH) secre on leading to increase in cor sol level.The effect of these endocrine and metabolic changes ul mately leads to increased neoglucogenesis and hyperglycemia.So this stress response can be quan fied by the incidence of hyperglycemia.Surgery itself causes a reduc on in insulin sensi vity leading to hyperglycemia, which is propor onal 9 to the length and technique of the procedure.The nega ve impact increase stress response and therefore the hyperglycemic response during surgery can be minimized by various surgical and anesthe c techniques such as minimally invasive surgeries and neuraxial 5,10,11 anesthesia.
Surgery itself causes a reduc on in insulin sensi vity, which is propor onal to the length and technique of the procedure.Although there has been large number of studies done comparing the increase in blood sugar levels between general anesthesia and epidural anesthesia there are few studies comparing the general anesthesia (GA) and spinal anesthesia (SA).This study was conducted with the objec ve of comparing blood sugar level between spinal and general anesthesia in surgical pa ents.The comparison between two groups are considered in the present study because large number of cases are undertaken everyday and an anesthesiologist should be familiar with each group regarding the increase in blood sugar level.

METHODOLOGY
This was a prospec ve compara ve study conducted at the department of anesthesiology and cri cal care of Manipal College of Medical Sciences, Pokhara.The study had a dura on of one and half year star ng from 2014 October to 2016 April.Ethical approval for the study was taken from the ins tu onal review commi ee.The study included 60 non diabe c pa ents of age between 20 to 60 years with ASA grading of I or II without difficult airway undergoing various surgical procedures.For sample size calcula on, we considered 5% as acceptable level of significance (Type I error) and 80% as power of study.On the basis of the study 12 conducted by Moller I W, Hjortso E, Krantz T, et al the effect size was considered 0.6 and considering 10% as drop out sample size was calculated to be 30 in each group.Group 1: Spinal anesthesia including 30 pa ents.Group 2: General anesthesia including 30 pa ents.
Pa ents with the ASA grade more than III, abnormal anatomy of spine, diabe c pa ent, pa ents with cardiovascular, respiratory, renal disease or neuromuscular disease, pa ents taking beta blockers and sta ns and pa ents undergoing cesarean sec on were excluded from the study.All the pa ents in the study were subjected to a detailed pre-anesthe c evalua on.Premedica on of the pa ents was done with Tab.Rani dine 150 mg, Tab.Metoclopramide 10 mg and Tab.Alprazolam 0.5 mg.Inj.0.5% Hyperbaric Bupivacaine was used for SA.In GA, pa ents were further premedicated with Inj.Fentanyl 1 mcg/kg IV.Induc on was done with Inj.Propofol 1.5 mg/kg IV and Inj.Vecuronium 0.1 mg/kg IV was used for muscle paralysis.General anesthesia was maintained with Oxygen (40%), Nitrous Oxide (60%), Isoflurane and Inj.Vecuronium 0.02 mg/kg/half an hourly intravenously.Minimum alveolar concentra on (MAC) of isoflurane was maintained at 2% at the me of induc on and 1-1.5% was used during maintenance of general anesthesia.MAC value displayed on the monitor was used to monitor the depth of anesthesia.Capillary blood glucose (CBG) level was measured half an hour before induc on of general anesthesia (GA) or before spinal anesthesia(SA).A er the induc on of GA or skin incision in SA, CBG level was measured at 15 minutes interval ll 1 hour of surgery.Non-invasive blood pressure, electrocardiogram, heart rate and oxygen satura on was con nuously monitored as soon as the pa ent was shi ed on the opera on table ll the end of the surgery in SA or ll the recovery of the pa ent from GA.

Sta s cal Analysis
Data was collected and entered in Microso Office Excel 7. Then data was analyzed using Sta s cal So ware IBM SPSS sta s cs Version 16.Con nuous data were presented as mean and standard devia on whereas categorical data were presented as frequency and percentage.Paired t test was used to compare mean for con nuous data and Chi square test was used for categorical data.P value < 0.05 was considered sta s cally significant.

RESULTS
The table 1 shows demographic distribu on and ASA grading of popula on undergoing this compara ve study that was sta s cally non significant between the two groups.
The table 2 shows the sta s cal analysis of the data collected at various me intervals before and a er spinal Paired sample t-test was applied and the p value was calculated for each me interval.The values obtained a er SA at all the me intervals were not sta s cally significant (p value < 0.05).
The table 3 shows the sta s cal analysis of the data collected at me intervals before general anesthesia and at 15, 30, 45 and 60 minutes a er general anesthesia.Data at each me interval is compared with the baseline values.The values obtained a er General Anesthesia at all the me intervals were sta s cally significant (p value < 0.05) when compared with the baseline value.
The table 4 shows comparison of blood glucose levels between Spinal (group 1) and General (group 2) anesthesia.Blood glucose level at baseline and 15 minutes a er anesthesia was comparable between the groups.While a er 15 minutes, there was significant difference (P<0.05) in the blood glucose level with the increasing sugar level in general anesthesia group.

DISCUSSION
Surgery elicits broad altera ons in hemodynamic, endocrinemetabolic and immune responses.Consequently, blood glucose levels increase in response to surgical stress.This stress-induced hyperglycemia represents a complex metabolic syndrome that compromises insulin resistance, reduced glucose clearance and rela ve insulinopenia.The degree of insulin resistance a er general surgery increases with the degree of surgical trauma.Stress-induced release of hormones such as cor sol, glucagon, epinephrine and growth hormone, among others, appear to be the main mediators.The results of various studies have shown that the choice of anesthesia technique affects intraopera ve stress response and thus significantly affects the outcome and morbidity of surgical pa ents and the reduc on of 13,14 postopera ve pain.
The present study observed that the blood glucose level was more stable during SA throughout the surgery.The SA produces significant sympathe c blockage which a enuates the stress induced physiological changes in 15 cardiovascular and endocrine system.The inhibi on of sympathe c system during SA results in significant decrease in cor sol level, decrease in adrenergic ac vity and inhibi on of renin angiotensin aldosterone system which ul mately helps to maintain a stable blood glucose level during surgery.This result is supported by the study 16 conducted by Pflug AE et al .They demonstrated that the surgical stress and the resultant hyperglycemia was produced by the s mulus from the afferent nerves from the site of ssue injury.SA inhibited these afferent nerves and thus the intra opera ve and post opera ve increase in epinephrine and norepinephrine were not observed.The similar result was also observed in the previous study where the SA inhibited the stress response to surgery by blun ng adrenocor cophic hormone, norepinephrine, growth hormone and cor sol response intra opera vely and in the 12 immediate postopera ve period.
We observed that there was a significant increase in the blood glucose level from the baseline a er the induc on of GA.The blood glucose level was poorly controlled throughout the surgery.The endotracheal intuba on and the surgical s mulus produce significant stress response with the increase in sympathe c ac vity which resulted in increased blood glucose level.The study observed that stress response induced by induc on of anesthesia and surgical s mulus was poorly inhibited by GA.This ongoing stress response increased the secre on of adrenaline, noradrenaline, cor sol level and resistance to insulin which resulted in poor control on blood glucose level during 17,18 GA.When SA was compared with the GA for blood glucose level intra opera vely, it was observed that there was significant difference in the blood glucose level a er 15 minutes of surgery.Pa ent with GA had significantly increased blood 9 glucose level as compared to SA. Milosavljevic SB et al. had clearly demonstrated that the periopera ve cor sol level was significantly decreased in SA as compared to GA.The same result was observed in 1 hr and 24 hour postopera ve period.Serum cor sol level is the determining factor for the blood glucose control and has posi ve correla on with the 9 glycaemia during GA.In our study, the following procedures: cholecystectomy, hernioplasty, appendectomy, tonsillectomy, vaginal hysterectomy and ORIF were undertaken and were of major severity and can poten ally cause an increase in cor sol secre on in response to surgical s mula on.Davis 19 FM et al.Observed that there was transient increase in the stress response and blood glucose level in SA.This sympathe c ac va on might be due to the anxiety of undergoing needle prick for regional injec on and surgical procedure.In the GA group blood glucose concentra on con nued to increase during surgery which is almost iden cal to the present study.20 Similarly, Go schalk A et al. found that the blood sugar level was significantly high both in diabe c and non diabe c pa ents during GA while intra opera ve blood glucose level was stable in pa ent receiving SA.Contradic ng our result and the previous studies, Amiri F et 21 al. observed that there was no significant change in the blood glucose level in GA and SA.Their study had SA in the lower segment.He jus fied that lower level block in surgical procedures such as cure age can't completely suppress the hormonal and metabolic changes.Our study did not include the pa ent with lower segment block.

CONCLUSION
The stress response to surgery results in the ac va on of the sympathe c system with the increase in adrenaline, noradrenaline, cor sol and blood glucose levels.The SA can significantly inhibit the surgical stress response producing a more stable blood glucose level as compared to GA.The blood glucose level was poorly controlled in GA due to the minimal blun ng of stress response.

RECOMMENDATION
As the stress response to surgery is compara vely less in spinal anesthesia, glycemic control is be er in spinal anesthesia as compared to general anesthesia.We recommend spinal anesthesia over general anesthesia when ever possible in reducing surgical stress response.

LIMITATIONS OF THE STUDY
The study didn't address other various factor that can affect the stress response and the blood glucose level.Blun ng of stress response during endotracheal intuba on, pain during intra opera ve period could be the possible reason for increase in blood glucose level in general anesthesia which were not explained in the study.The surgical stress depends on the type of surgery.Our study did not maintain a uniformity in the type of surgery which might have produced different level of surgical stress thus varia on in blood sugar level.
-2758 (Print) 2542-2804 (Online) each me interval is compared with the baseline values.