Sympathetic Response to Postural Perturbation in Stance

The purpose of the present study was to elucidate whether the sympathetic response to perturbation in stance represents multiple mental responses, whether perturbation-induced fear of fall is one of the mental responses, and whether the sympathetic response is task specific. While healthy humans maintained stance, the support surface of the feet translated in the forward or backward direction. The phasic electrodermal response (EDR), representing the sympathetic response, appeared 1–1.5 s after the support surface translation. Mostly, perturbation-induced EDRs comprised one peak, but some EDRs were comprised of two peaks. The onset latency of the two-peak EDR was much shorter than that of the one-peak EDR. The second peak latency of the two-peak EDR was similar to the peak latency of the one-peak EDR, indicating that the first peak of the two-peak EDR was an additional component preceding the one-peak EDR. This finding supports a view that perturbation-induced EDR in stance sometimes represents multiple mental responses. The amplitude of the EDR had a positive and significant correlation with fear, indicating that perturbation-induced EDR in stance partially represents perturbation-induced fear of fall. The EDR amplitude was dependent on the translation amplitude and direction, indicating that perturbation-induced EDR in stance is a task specific response. The EDR appeared earlier when the participants prepared to answer a question or when the perturbation was self-triggered, indicating that adding cognitive load induces earlier perturbation-induced mental responses.

A Letter from Boris Zaitsev to Yuly Aykhenvald

: A letter on July 29, 1927 from B.K. Zaitsev to Yu.I. Aykhenvald is published and commented. The history of the relationship between Zaitsev and Aykhenvald is briefly outlined. More over the Letter of the Board of the Union of Russian Journalists and Writers of Germany with Gorky’s sympathetic response to Dzerzhinsky’s death is cited both with the review of the responses to the “Letter of Russian Writers” (1927) in the newspaper “Rul”.

Intra Venous Butorphanol versus Intravenous Nalbuphine for (Intra Operative) Balanced Anaesthesia and Post Operative Analgesic Effect in Patients Undergoing Laparoscopic Surgery

Laparoscopic surgery has replaced many of the open surgeries because of its advantages. Both the groups of drugs have hemodynamic stability, analgesia, sedation and decrease the requirement of other anesthetic drugs. So we have chosen Butorphanol and Nalbuphine to study the analgesia and hemodynamic changes in both groups. In our study mean heart rate was lower in Butorphanol group compare to Nalbuphine group. Similarly fifty patients of ASA I&II scheduled for elective laparoscopic surgery, were randomized in to butorphanol group and nalbuphine group. It was observed that there was significant rise in systolic blood pressure & Diastolic Blood pressure after intubation in fentanyl group compare to Butorphanol. This study finds that suppression of sympathetic response to laryngoscopy and intubation was better with Butorphanol than Fentanyl. This study analysis indicates that both Butorphanol and Nalbuphine help in maintaining a steady haemodynamic state all throughout the procedure.

Prediction of Blood Pressure Change During Surgical Incision Under Opioid Analgesia Using a New Opioid Sensitivity Index: A Cross-Sectional Study

Opioid inhibition of nociceptive stimuli varies in individuals and is difficult to titrate. We have reported the vascular stiffness value (K) as a standard monitor to quantify sympathetic response with high accuracy. On the contrary, among individuals, a considerable variation in the rate of change in K for constant pain has been observed. In this study, we proposed a new index, minimum evoked current of K (MECK) and evaluated its accuracy in predicting sympathetic response to nociceptive stimuli under constant opioid administration. Thirty patients undergoing open surgery under general anesthesia were included. After anesthetic induction, remifentanil was administered at a constant concentration of 2 ng/ml at the effect site followed by tetanus stimulation. MECK was defined as the minimal current needed to produce a change in K. MECK significantly (P < 0.001) correlated with the rate of change of systolic blood pressure during skin incision (ROCBP). Bland-Altman plot analysis using the predicted ROCBP calculated from MECK and the measured ROCBP showed that the prediction equation for ROCBP was highly accurate. This study showed the potential of MECK to predict blood pressure change during surgical incision under opioid analgesia.

“EVALUATION OF DEXMEDETOMIDINE ON HEMODYNAMICS IN PATIENTS UNDERGOING LAPAROSCOPIC CHOLECYSTECTOMY”

The physiological response to surgical stress and anaesthesia is well documented. Laparoscopic surgery which involves insufflation with carbon dioxideproduces undesirable responses like hypertension, tachycardia and dysrhythmias. Introduction of Dexmedetomidine which is highly specific and selectiveα2 adrenoceptor agonist has been tried in various studies to modify the stress response to surgery and to have a pleasant anaesthetic outcome with minimal cardiovascular changes. In our present study we have taken the pharmacological advantage of Dexmedetomidine to study the various cardiovascular parameters at different periods during the laparoscopic procedure. The aim is to studythe effectiveness of Dexmedetomidineinattenuating the sympathetic response tolaryngoscopy and endotracheal intubation and in maintaining the hemodynamic stability in laparoscopic cholecystectomy. Materials & Methods: 30 ASA I and II patients of either sex, scheduled for elective Laparoscopic Cholecystectomy under General anaesthesia were randomly allocated to receive either 1mcg/kg of Dexmedetomidine in 100ml of 0.9% normal saline (Group D,n=30) or 100ml of 0.9% normal saline(Group S, n=30) 30min beforeinduction. Results: In patients who received Dexmedetomidine there was a statistically significant differencein heartrate, systolic blood pressure, diastolic blood pressure and meanarterial pressures during Laparoscopy and Intubation. Conclusion: Dexmedetomidine when given as a premedication before Laparoscopic Cholecystectomy attenuates the sympathetic response to laryngoscopy and intubation and provides stable intra operative hemodynamics.

“EVALUATION OF DEXMEDETOMIDINE ON HEMODYNAMICS IN PATIENTS UNDERGOING LAPAROSCOPIC CHOLECYSTECTOMY

Background: The physiological response to surgical stress and anaesthesia is well documented. Laparoscopic surgery which involves insufflation with carbon dioxideproduces undesirable responses like hypertension, tachycardia and dysrhythmias. Introduction of Dexmedetomidine which is highly specific and selectiveα2 adrenoceptor agonist has been tried in various studies to modify the stress response to surgery and to have a pleasant anaesthetic outcome with minimal cardiovascular changes. In our present study we have taken the pharmacological advantage of Dexmedetomidine to study the various cardiovascular parameters at different periods during the laparoscopic procedure. The aim is to studythe effectiveness of Dexmedetomidineinattenuating the sympathetic response tolaryngoscopy and endotracheal intubation and in maintaining the hemodynamic stability in laparoscopic cholecystectomy. Materials & Methods: 30 ASA I and II patients of either sex, scheduled for elective Laparoscopic Cholecystectomy under General anaesthesia were randomly allocated to receive either 1mcg/kg of Dexmedetomidine in 100ml of 0.9% normal saline (Group D,n=30) or 100ml of 0.9% normal saline(Group S, n=30) 30min beforeinduction. Results: In patients who received Dexmedetomidine there was a statistically significant differencein heartrate, systolic blood pressure, diastolic blood pressure and meanarterial pressures during Laparoscopy and Intubation. Conclusion: Dexmedetomidine when given as a premedication before Laparoscopic Cholecystectomy attenuates the sympathetic response to laryngoscopy and intubation and provides stable intra operative hemodynamics.