Cardiovascular Responses to Unilateral, Bilateral, Upper, and Lower Limbs Resistance Exercise

The effects of different resistance exercises on cardiovascular responses remain elusive. Therefore, the present study aimed to investigate acute cardiovascular responses to unilateral and bilateral upper and lower limb resistance exercise. Young healthy males (n = 22; 26.9 ± 5.4 years, 170.0 ± 6.0 cm, 77.0 ± 10.8 kg) participated in the present study. Four experimental sessions were carried out, each consisting of one of the four exercises: unilateral and bilateral knee extension, unilateral and bilateral biceps curl. Cardiovascular responses (heart rate; HR, systolic blood pressure; SBP, and rate-pressure product; RPP) were measured at rest and after each of the three sets in each resistance exercise. All sets were performed until concentric muscle failure with a rest interval of two min. The HR, SBP, and RPP progressively increased during all sessions with uni- and bilateral exercises of the lower and upper limbs. Importantly, bilateral exercises, mainly of the lower limbs, induced greater increases in HR, and RPP than unilateral exercises of the upper and lower limbs. Regarding SBP, bilateral knee extension exercise induced greater increases than unilateral biceps curl. From a practical standpoint, exercise professionals may consider prescribing unilateral upper and lower limb exercises to alleviate cardiovascular stress, because even when performed until concentric muscle failure, this exercise mode seems to induce lower cardiovascular demand during the resistance training session.

Phantom limb therapy improves cortical efficiency of the sensorimotor network in a targeted muscle reinnervation amputee: a case report

Targeted muscle reinnervation (TMR) surgery involves the coaptation of amputated nerves to nearby motor nerve branches with the purpose of reclosing the neuromuscular loop in order to reduce phantom limb pain. The purpose of this case study was to create a phantom limb therapy protocol for an amputee after undergoing TMR surgery, where the four main nerves of his right arm were reinnervated into the chest muscles. The goal of this phantom limb therapy was to further strengthen these newly formed neuromuscular closed loops. The case participant (male, 21- years of age, height = 5'8″ and weight = 134 lbs) presented 1- year after a trans-humeral amputation of the right arm along with TMR surgery and participated in phantom limb therapy for 3 months. Data collections for the subject occurred every 2 weeks for 3 months. During the data collections, the subject performed various movements of the phantom and intact limb specific to each reinnervated nerve and a gross manual dexterity task (Box and Block Test) while measuring brain activity and recording qualitative feedback from the subject. The results demonstrated that phantom limb therapy produced significant changes of cortical activity, reduced fatigue, fluctuation in phantom pain, improved limb synchronization, increased sensory sensation, and decreased correlation strength between intra-hemispheric and inter-hemispheric channels. These results suggest an overall improved cortical efficiency of the sensorimotor network. These results add to the growing knowledge of cortical reorganization after TMR surgery, which is becoming more common to aid in the recovery after amputation. More importantly, the results of this study suggest that the phantom limb therapy may have accelerated the decoupling process, which provides direct clinical benefits to the patient such as reduced fatigue and improved limb synchronization.

Enhanced external counterpulsation ameliorates endothelial dysfunction and elevates exercise tolerance in patients with coronary artery disease

PURPOSE

Enhanced external counterpulsation (EECP) is a new non-drug treatment for coronary artery disease (CAD). However, the long-term effect of EECP on endothelial dysfunction and exercise tolerance, and the relationship between the changes in the endothelial dysfunction and exercise tolerance in the patients with coronary heart disease are still unclear.

METHODS

A total of 240 patients with CAD were randomly divided into EECP group (n = 120) and control group (n = 120). All patients received routine treatment of CAD as the basic therapy. Patients in the EECP group received 35 1-h daily sessions of EECP during 7 consecutive weeks while the control group received the same treatment course, but the cuff inflation pressure was 0-10 mmHg. Peak systolic velocity (PSV), end diastolic velocity (EDV), resistance index (RI), and inner diameter (ID) of the right carotid artery were examined using a Color Doppler Ultrasound and used to calculate the fluid shear stress (FSS). Serum levels of human vascular endothelial cell growth factor (VEGF), vascular endothelial cell growth factor receptor 2 (VEGFR2), and human angiotensin 2 (Ang2) were determined by enzyme-linked immunosorbent assay (ELISA). Exercise load time, maximal oxygen uptake (VO2max ), metabolic equivalent (METs), anaerobic threshold (AT), peak oxygen pulse (VO2max/HR) were assessed using cardiopulmonary exercise tests.

RESULTS

After 1 year follow-up, the EDV, PSV, ID, and FSS were significantly increased in the EECP group (P < 0.05 and 0.01, respectively), whereas there were no significant changes in these parameters in the control group. The serum levels of VEGF and VEGFR2 were elevated in the EECP and control groups (all P < 0.05). However, the changes in VEGF and VEGFR2 were significantly higher in the EECP group than in the control group (P < 0.01). The serum level of Ang2 was decreased in the EECP group (P < 0.05) and no obvious changes in the control group. As for exercise tolerance of patients, there were significant increases in the exercise load time, VO2max, VO2max/HR, AT and METs in the EECP group (all P < 0.05) and VO2max and METs in the control group (all P < 0.05). Correlation analyses showed a significant and positive correlations of VEGF and VEGFR2 levels with the changes in FSS (all P < 0.001). The correlations were still remained even after adjustment for confounders (all Padjustment < 0.001). Linear regression displays the age, the medication of ACEI (angiotensin-converting enzyme inhibitors) or ARB (angiotensin receptor blockers), the diabetes and the changes in VEGF and VEGFR2 were positively and independently associated with the changes in METs after adjustment for confounders (all Padjustment < 0.05).

CONCLUSION

The data of our study suggested that EECP is a useful therapeutic measurement for amelioration of endothelial dysfunction and long-term elevation of exercise tolerance for patients with coronary heart disease.

CLINICAL TRIAL REGISTRATION

[http://www.chictr.org.cn/], identifier [ChiCTR1800020102].

The effect of intranasal dexmedetomidine on hemodynamic disturbances caused by laryngoscopy and endotracheal intubation

BACKGROUND

Induced stimulation while endotracheal intubating affects hemodynamic status. The present study compares the hemodynamic changes caused by endotracheal intubating after administering two doses of intranasal Dexmedetomidine.

METHODS

In an experimental (before-after) trial, 88 patients undergoing general anesthesia enrolled in the study. The Iranian Register of Clinical Trial (IRCT) code of the study was IRCT20160307026950N15 (https://en.irct.ir/trial/39269). Patients were allocated to two intervention groups and one control group by random. Intranasal Dexmedetomidine and Normal saline 0.9% were administrated 30 minutes before induction of anesthesia. (1 μg/kg Dexmedetomidine in group 1, 2 μg/kg Dexmedetomidine in group 2 and 1 mg Normal saline 0.9% in group 3). Vital signs and hemodynamic parameters were measured and recorded in minutes 1, 3, 5, and 10th after induction. Data analysis was done by ANOVA and Chi-square tests.

RESULTS

Heart rate, systolic and diastolic blood pressure, and mean arterial pressure were reduced in patients receiving dexmedetomidine (P<0.05), but there were no significant changes in the control group. In arterial oxygenation (P>0.05), there was no significant difference between the three groups in the arterial blood oxygen amount.

CONCLUSION

Premedication of intranasal dexmedetomidine influences the hemodynamic changes due to anesthesia induction. The dose of 2 µg/kg is better than one µg/kg in improving the hemodynamic state following intubation.

Effects of Enhanced External Counterpulsation With Different Sequential Levels on Lower Extremity Hemodynamics

Objective: This study aimed to investigate acute hemodynamics of lower extremities during enhanced external counterpulsation with a three-level sequence at the hips, thighs, and calves (EECP-3), two-level sequence at the hips and thighs (EECP-2), and single leg three-level sequence (EECP-1).

Methods: Twenty healthy volunteers were recruited in this study to receive a 45-min EECP intervention. Blood flow spectrums in the anterior tibial artery, posterior tibial artery, and dorsalis pedis artery were imaged by Color Doppler ultrasound. Mean flow rate (FR), area, pulsatility index (PI), peak systolic velocity (PSV), end-diastolic velocity (EDV), mean flow velocity (MV), and systolic maximum acceleration (CCAs) were sequentially measured and calculated at baseline during EECP-3, EECP-1, and EECP-2.

Results: During EECP-3, PI, PSV, and MV in the anterior tibial artery were significantly higher, while EDV was markedly lower during EECP-1, EECP-2, and baseline (all P < 0.05). Additionally, ACCs were significantly elevated during EECP-3 compared with baseline. Moreover, FR in the anterior tibial artery was significantly increased during EECP-3 compared with baseline (P = 0.048). During EECP-2, PI and MV in the dorsalis pedis artery were significantly higher and lower than those at baseline, (both P < 0.05). In addition, FR was markedly reduced during EECP-2 compared with baseline (P = 0.028). During EECP-1, the area was significantly lower, while EDV was markedly higher in the posterior tibial artery than during EECP-1, EECP-2, and baseline (all P < 0.05). Meanwhile, FR of the posterior tibial artery was significantly reduced compared with baseline (P = 0.014).

Conclusion: Enhanced external counterpulsation with three-level sequence (EECP-3), EECP-2, and EECP-1 induced different hemodynamic responses in the anterior tibial artery, dorsalis pedis artery, and posterior tibial artery, respectively. EECP-3 acutely improved the blood flow, blood flow velocity, and ACCs of the anterior tibial artery. In addition, EECP-1 and EECP-2 significantly increased the blood flow velocity and peripheral resistance of the inferior knee artery, whereas they markedly reduced blood flow in the posterior tibial artery.

Immediate Effects of Whole-Body Vibration Associated with Squatting Exercises on Hemodynamic Parameters in Sarcopenic Older People: A Randomized Controlled Trial

Whole-body vibration (WBV) exercises have recently been introduced as a nonpharmacological therapeutic strategy for sarcopenic older people. The present study aimed to evaluate the effect of WBV exercise on hemodynamic parameters in sarcopenic older people. Forty older people, divided into groups of nonsarcopenic (NSG = 20) and sarcopenic (SG = 20), participated in the study and were cross randomized into two interventions of eight sets of 40 s each, these being squatting with WBV and squatting without WBV. Heart rate (HR), peak heart rate (peak HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), double product (DP), mean arterial pressure (MAP), and subjective perception of effort (SPE), were assessed at baseline, during, and after a single WBV session. The HR, peak HR, and DP variables were similar at baseline between groups. WBV exercise increased all the hemodynamic parameters both during and immediately after the intervention, in both groups (SG and NSG). The MAP values were similar at baseline between groups; however, in the NSG there was a significant increase during and immediately after the squatting with WBV intervention (p < 0.05). The HR behavior, in both groups, showed that there was an increase in HR after the first set of exercises with vibration and this increase was maintained until the final set. The absence of adverse effects of WBV exercise on the cardiovascular system and fatigue suggests this exercise modality is adequate and safe for sarcopenic older people.

Acute Effect of Enhanced External Counterpulsation on the Carotid Hemodynamic Parameters in Patients With High Cardiovascular Risk Factors

Purpose

Enhanced external counterpulsation (EECP) can improve carotid circulation in patients with coronary artery disease. However, the response of carotid hemodynamic parameters induced by EECP in patients with high cardiovascular risk factors remains to be clarified. This study aimed to investigate the acute effect of EECP on the hemodynamic parameters in the carotid arteries before, during, and immediately after EECP in patients with hypertension, hyperlipidemia, and type 2 diabetes.

Methods

Eighty-three subjects were recruited into this study to receive 45-min EECP, including patients with simple hypertension (n = 21), hyperlipidemia (n = 23), type 2 diabetes (n = 18), and healthy subjects (n = 21). Hemodynamic parameters in both common carotid arteries (CCAs) were measured and calculated from Doppler ultrasound images. Peak systolic velocity (PSV), end-diastolic velocity (EDV), mean inner diameter (ID), systolic/diastolic flow velocity ratio (VS/VD), flow rate (FR), and resistance index (RI) were monitored before, during, and immediately after 45-min EECP.

Results

EDV and VS/VD were significantly reduced, while RI of CCAs was significantly increased among four groups during EECP (all P < 0.01). Additionally, the ID of CCAs and the FR of left CCA increased in patients with hyperlipidemia during EECP (P < 0.05). PSV of left CCA was reduced in patients with type 2 diabetes (P < 0.05). Moreover, immediately after EECP, ID was significantly higher in patients with hyperlipidemia. The RI of patients with hypertension and PSV and VS/VD of patients with type 2 diabetes were significantly lower compared with baseline (all P < 0.05).

Conclusion

EECP created an acute reduction in EDV, PSV, and VS/VD, and an immediate increase in the RI, FR, and ID of CCAs among the four groups. Additionally, a single 45-min session of EECP produced immediate improvement in the ID of patients with hyperlipidemia, the RI of patients with hypertension, and the PSV and VS/VD of patients with type 2 diabetes. The different hemodynamic responses induced by EECP may provide theoretical guidance for making personalized plans in patients with different cardiovascular risk factors.

Tinnitus and auditory cortex; Using adapted functional near-infrared-spectroscopy to expand brain imaging in humans

Objectives

Phantom sound perception (tinnitus) may arise from altered brain activity within auditory cortex. Auditory cortex neurons in tinnitus animal models show increased spontaneous firing rates. This may be a core characteristic of tinnitus. Functional near‐infrared spectroscopy (fNIRS) has shown similar findings in human auditory cortex. Current fNIRS approaches with cap recordings are limited to ∼3 cm depth of signal penetration due to the skull thickness. To address this limitation, we present an innovative fNIRS approach via probes adapted to the external auditory canal. The adapted probes were placed deeper and closer to temporal lobe of the brain to bypass confining skull bone and improve neural recordings.

Methods

Twenty adults with tinnitus and 20 nontinnitus controls listened to periods of silence and broadband noise (BBN) during standard cap and adapted ear canal fNIRS neuroimaging. The evaluators were not blinded, but the protocol and postprocessing for the two groups were identical.

Results

Standard fNIRS measurements in participants with tinnitus revealed increased auditory cortex activity during silence that was suppressed during auditory stimulation with BBN. Conversely, controls displayed increased activation with noise but not during silence. Importantly, adapted ear canal fNIRs probes showed similar hemodynamic responses seen with cap probes in both tinnitus and controls.

Conclusions

In this proof of concept study, we have successfully fabricated, adapted, and utilized a novel fNIRS technology that replicates established findings from traditional cap fNIRS probes. This exciting new innovation, validated by replicating previous and current cap findings in auditory cortex, may have applications to future studies to investigate brain changes not only in tinnitus but in other pathologic states that may involve the temporal lobe and surrounding brain regions.

Level of Evidence

NA.

Effects of cranial electrotherapy stimulation on preoperative anxiety and blood pressure during anesthetic induction in patients with essential hypertension

Objective

Cranial electrotherapy stimulation (CES) is a non-invasive treatment that improves symptoms such as anxiety and pain. The purpose of this study was to analyze the effect of CES pretreatment on levels of preoperative anxiety, pain, and hemodynamic responses—especially changes in blood pressure—during anesthetic induction in patients with essential hypertension.

Methods

Eighty patients undergoing general anesthesia were randomly assigned to receive either no pretreatment (control group, n = 40) or CES pretreatment (CES group, n = 40). Anxiety scores, systolic and diastolic blood pressures, mean arterial pressure, and heart rate were measured in the general ward the evening before surgery, as well as in the preoperative holding area, operating room, and after intubation. Withdrawal responses to rocuronium injection were also measured.

Results

Anxiety scores in the operating room were significantly lower in the CES group. Withdrawal responses to rocuronium injection were also significantly lower in the CES group. There were no significant differences in hemodynamic values between the two groups.

Conclusions

CES pretreatment reduces both preoperative anxiety levels and withdrawal responses to rocuronium injection. However, it does not have a significant effect on hemodynamic responses.

NICA: A Novel Toolbox for Near-Infrared Spectroscopy Calculations and Analyses

Functional near-infrared spectroscopy (fNIRS) measures the functional activity of the cerebral cortex. The concentration changes of oxygenated (oxy-Hb) and deoxygenated hemoglobin (deoxy-Hb) can be detected and associated with activation of the cortex in the investigated area (neurovascular coupling). Recorded signals of hemodynamic responses may contain influences from physiological signals (systemic influences, physiological artifacts) which do not originate from the cerebral cortex activity. The physiological artifacts contain the blood pressure (BP), respiratory patterns, and the pulsation of the heart. In order to perform a comprehensive analysis of recorded fNIRS data, a proper correction of these physiological artifacts is necessary. This article introduces NICA – a novel toolbox for near-infrared spectroscopy calculations and analyses based on MATLAB. With NICA it is possible to process and visualize fNIRS data, including different signal processing methods for physiological artifact correction. The artifact correction methods used in this toolbox are common average reference (CAR), independent component analysis (ICA), and transfer function (TF) models. A practical example provides results from a study, where NICA was used for analyzing the measurement data, in order to demonstrate the signal processing steps and the physiological artifact correction. The toolbox was developed for fNIRS data recorded with the NIRScout 1624 measurement device and the corresponding recording software NIRStar.

Systemic and regional hemodynamic response to activation of the exercise pressor reflex in patients with peripheral artery disease

Patients with peripheral artery disease (PAD) have an accentuated exercise pressor reflex (EPR) during exercise of the affected limb. The underlying hemodynamic changes responsible for this, and its effect on blood flow to the exercising extremity, are unclear. We tested the hypothesis that the exaggerated EPR in PAD is mediated by an increase in total peripheral resistance (TPR), which augments redistribution of blood flow to the exercising limb. Twelve patients with PAD and 12 age- and sex-matched subjects without PAD performed dynamic plantar flexion (PF) using the most symptomatic leg at progressive workloads of 2-12 kg (increased by 1 kg/min until onset of fatigue). We measured heart rate, beat-by-beat blood pressure, femoral blood flow velocity (FBV), and muscle oxygen saturation (SmO2) continuously during the exercise. Femoral blood flow (FBF) was calculated from FBV and baseline femoral artery diameter. Stroke volume (SV), cardiac output (CO), and TPR were derived from the blood pressure tracings. Mean arterial blood pressure and TPR were significantly augmented in PAD compared with control during PF. FBF increased during exercise to an equal extent in both groups. However, SmO2 of the exercising limb remained significantly lower in PAD compared with control. We conclude that the exaggerated pressor response in PAD is mediated by an abnormal TPR response, which augments redistribution of blood flow to the exercising extremity, leading to an equal rise in FBF compared with controls. However, this increase in FBF is not sufficient to normalize the SmO₂ response during exercise in patients with PAD.NEW & NOTEWORTHY In this study, peripheral artery disease (PAD) patients and healthy control subjects performed graded, dynamic plantar flexion exercise. Data from this study suggest that previously reported exaggerated exercise pressor reflex in patients with PAD is driven by greater vasoconstriction in nonexercising vascular territories which also results in a redistribution of blood flow to the exercising extremity. However, this rise in femoral blood flow does not fully correct the oxygen deficit due to changes in other mechanisms that require further investigation.

Effects of ultrasound guided ganglion stellate blockade on intraoperative and postoperative hemodynamic responses in laparoscopic gynecologic surgery

Introduction

Laparoscopic gynecologic surgery is one of the most well-known procedures. Pneumoperitoneum with carbon dioxide insufflation can cause unfavorable hemodynamic effects due to catecholamine and vasopressin release.

Aim

To examine the effects of stellate ganglion block on hemodynamic response and postoperative pain.

Material and methods

In a prospective double blinded randomized parallel study we included 40 patients with ASA physical status I and II, aged between 18 and 50 years with a gynecologic problem candidate for laparoscopic surgery under general anesthesia. The patients were randomly divided into two groups. Fifteen minutes before anesthesia induction, the patients underwent ultrasound guided stellate ganglion block with 10 ml of lidocaine 1% and the control group underwent stellate ganglion block using 10 ml of distilled water as placebo. After induction of general anesthesia, systolic and diastolic blood pressure and heart rate were recorded, especially after blowing of CO₂ gas, the position change, depletion of CO₂, and tracheal extubation in recovery. The postoperative pain was calculated using the visual analogue scale (VAS) at three times (0, 30, and 24 h after surgery).

Results

Our results showed that mean systolic and diastolic blood pressure and heart rate did not show any significant difference at the measurement times (p > 0.05), and mean VAS of patients in the two groups was significantly different for the three measurement times except 24 h after surgery (p < 0.05).

Conclusions

Stellate ganglion block before laparoscopic gynecologic surgery has no significant effect on intraoperative and postoperative hemodynamic responses; however, it can decrease VAS in the early postoperative period.

Effect of different doses of intravenous oxycodone and fentanyl on intubation-related hemodynamic responses: A prospective double-blind randomized controlled trial (CONSORT)

BACKGROUND

Intubation using direct laryngoscopy is a risky and painful procedure that is associated with undesirable hemodynamic changes such as tachycardia, hypertension, and arrhythmia. Recently, intravenous oxycodone was introduced and used for the control of acute postoperative pain and to attenuate intubation-related hemodynamic responses (IRHRs), but there is insufficient information regarding its proper dosage. We investigated the attenuating effects of different doses of oxycodone and fentanyl on IRHRs.

METHODS

For calculating oxycodone effective dose (ED95), which attenuated all IRHR changes to less than 20% over baseline values in 95% of male patients at 1 minute after intubation, oxycodone 0.1 mg/kg was injected for the first patient 1 hour before intubation, and the next dose for each subsequent patient was determined by the response of the previous patient using Dixon up-and-down method with an interval of 0.01 mg/kg. After obtaining the predictive oxycodone ED95, 148 patients were randomly allocated to groups receiving normal saline (group C), oxycodone ED95 (group O1), oxycodone 2 × ED95 (group O2), or fentanyl 2 μg/kg (group F). We recorded the incidence of "success" as a less than 20% change from baseline values in all IRHRs 1 minute after intubation.

RESULTS

The predictive oxycodone ED95 was 0.091 (0.081-0.149) mg/kg. The incidence of "success" was highest in group O2 (75.7%), followed by group O1 (62.2%) and group F (45.9%) with significant differences between the groups (P < .001). The systolic, diastolic, mean arterial pressure, and heart rate were not significantly different among groups after administration of either oxycodone or fentanyl. The percentage hemodynamic changes of the group O2 were significantly lower than those of groups F and O1, but the absolute percentage hemodynamic changes were not significantly different among groups F, O1, and O2. The recalculated oxycodone ED95 with probit analysis (0.269 mg/kg) was needed to prevent any arterial pressure and heart rate changes.

CONCLUSIONS

Oxycodone 0.182 mg/kg is more effective in attenuating all IRHRs than fentanyl 2 μg/kg with safe hemodynamic changes. Further research is required to determine if the recalculated oxycodone ED95 (0.269 mg/kg) is also effective and hemodynamically safe for preventing all IRHRs.

Functional Ultrasound Imaging of Spinal Cord Hemodynamic Responses to Epidural Electrical Stimulation: A Feasibility Study

This study presents the first implementation of functional ultrasound (fUS) imaging of the spinal cord to monitor local hemodynamic response to epidural electrical spinal cord stimulation (SCS) on two small and large animal models. SCS has been successfully applied to control chronic refractory pain and recently was evolved to alleviate motor impairment in Parkinson's disease and after spinal cord injury. At present, however, the mechanisms underlying SCS remain unclear, and current methods for monitoring SCS are limited in their capacity to provide the required sensitivity and spatiotemporal resolutions to evaluate functional changes in response to SCS. fUS is an emerging technology that has recently shown promising results in monitoring a variety of neural activities associated with the brain. Here we demonstrated the feasibility of performing fUS on two animal models during SCS. We showed in vivo spinal cord hemodynamic responses measured by fUS evoked by different SCS parameters. We also demonstrated that fUS has a higher sensitivity in monitoring spinal cord response than electromyography. The high spatial and temporal resolutions of fUS were demonstrated by localized measurements of hemodynamic responses at different spinal cord segments, and by reliable tracking of spinal cord responses to patterned electrical stimulations, respectively. Finally, we proposed optimized fUS imaging and post-processing methods for spinal cord. These results support feasibility of fUS imaging of the spinal cord and could pave the way for future systematic studies to investigate spinal cord functional organization and the mechanisms of spinal cord neuromodulation in vivo.

Influence of magnesium sulfate on hemodynamic responses during laparoscopic cholecystectomy: A meta-analysis of randomized controlled studies

BACKGROUND

The impact of magnesium sulfate on hemodynamic responses during laparoscopic cholecystectomy remains controversial. We conduct a systematic review and meta-analysis to explore the influence of magnesium sulfate on hemodynamic responses for laparoscopic cholecystectomy.

METHODS

We search PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through June 2018 for randomized controlled trials (RCTs) assessing the effect of magnesium sulfate on hemodynamic responses for laparoscopic cholecystectomy. Meta-analysis is performed using the random-effect model.

RESULTS

Four RCTs involving 208 patients are included in the meta-analysis. Overall, compared with control group in laparoscopic cholecystectomy, intravenous magnesium sulfate is associated with systolic blood pressure at 30 minutes [Std. MD = -1.34; 95% confidence interval (95% CI) = -1.86 to -0.82; P < .00001], diastolic blood pressure at 30 minutes (Std. MD = -1.40; 95% CI = -1.86 to -0.94; P < .00001), mean arterial pressure at 30 minutes (Std. MD = -1.19; 95% CI = -1.91 to -0.46; P = .001), systolic blood pressure at 10 minutes (Std. MD = -1.61; 95% CI = -2.08 to -1.13; P < .00001), diastolic blood pressure at 10 minutes (Std. MD = -1.54; 95% CI = -2.68 to -0.40; P = .008), heart rate at 30 minutes (Std. MD = -2.09; 95% CI = -2.87 to -1.32; P < .00001), but results in prolonged extubation time (Std. MD = 0.96; 95% CI = 0.18-1.74; P = .02).

CONCLUSION

Magnesium sulfate can reduce blood pressure, but with the increase in extubation time for laparoscopic cholecystectomy.

Prostaglandin E1-Mediated Collateral Recruitment Is Delayed in a Neonatal Rat Stroke Model

While arterial reflow after a stroke represents an important challenge for better outcomes, it is also very important that sudden recanalization does not produce local oxidative and nitrogen species, deleterious for the brain and more particularly the immature brain. Our objective was to determine whether a supply in prostaglandin (Pg) E1 (Alprostadil), via its action on arterial pressure, might progressively improve cerebral reperfusion in a neonatal stroke model. Arterial blood flow was measured using ultrasonography. Rate-limiting and Pg terminal synthesizing enzymes were evaluated using reverse-transcriptase polymerase chain reaction. Our data suggests that a supply in PgE1 might delay and improve the ipsilateral reperfusion by decreasing thromboxane A synthase-1 gene, the density of reactive astrocytes and lesion volume.

Effects of combined epidural and general anesthesia on intraoperative hemodynamic responses, postoperative cellular immunity, and prognosis in patients with gallbladder cancer: A randomized controlled trial

BACKGROUND

This study is supposed to investigate the effects of combined epidural and general anesthesia on intraoperative hemodynamic responses, postoperative cellular immunity, and prognosis in patients with gallbladder cancer (GBC).

METHODS

One hundred forty-four GBC patients were selected and randomly divided into the general anesthesia (GA) group and the combined epidural-general anesthesia (CEGA) group. Before anesthesia induction (t0), at intubation (t1), at the beginning of surgery (t2), 5 minutes after pneumoperitoneum (t3), at the end of surgery (t4), after recovery of spontaneous breathing (t5), after regaining consciousness (t6), and after extubation (t7), the heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and the depth of anesthesia (bispectral index [BIS]) were detected. Blood samples were separately collected 30 minutes before anesthesia induction (T1), 2 hours after the beginning of surgery (T2), at the end of surgery (T3), 1 day after surgery (T4), 3 days after surgery (T5). The survival rates of T cell subsets (CD3+, CD4+, CD8+, CD4+/CD8+) and natural killer (NK) cells were determined by flow cytometry. Postoperative nausea and vomiting (PONV), visual analog scale (VAS), and sedation-agitation scale (SAS) were performed to assess postoperative adverse reactions. A 3-year follow-up was conducted.

RESULTS

Compared with the GA group, the CEGA group had significant lower SBP values at t5 and t6, lower DBP values at t1, t3, t4, and t5, lower HR values at t1 and t5, and higher BIS values at t4, t5, t6, and t7. No PONV was observed in the CEGA group. In comparison to the GA group, the VAS was markedly increased and survival rates of CD3+, CD4+, and CD4+/CD8+ cells were increased at T2, T3, T4, and T5 in the CEGA group. The 1-year, 2-year, and 3-year survival rates were not evidently different between the CEGA group and the GA group.

CONCLUSION

Our study provides evidence that the combined epidural-general anesthesia might attenuate intraoperative hemodynamic responses and improve postoperative cellular immunity, so that it might be a more available anesthesia method for GBC patients.

Melodic Contour Identification Reflects the Cognitive Threshold of Aging

Cognitive decline is a natural phenomenon of aging. Although there exists a consensus that sensitivity to acoustic features of music is associated with such decline, no solid evidence has yet shown that structural elements and contexts of music explain this loss of cognitive performance. This study examined the extent and the type of cognitive decline that is related to the contour identification task (CIT) using tones with different pitches (i.e., melodic contours). Both younger and older adult groups participated in the CIT given in three listening conditions (i.e., focused, selective, and alternating). Behavioral data (accuracy and response times) and hemodynamic reactions were measured using functional near-infrared spectroscopy (fNIRS). Our findings showed cognitive declines in the older adult group but with a subtle difference from the younger adult group. The accuracy of the melodic CITs given in the target-like distraction task (CIT2) was significantly lower than that in the environmental noise (CIT1) condition in the older adult group, indicating that CIT2 may be a benchmark test for age-specific cognitive decline. The fNIRS findings also agreed with this interpretation, revealing significant increases in oxygenated hemoglobin (oxyHb) concentration in the younger (p < 0.05 for Δpre - on task; p < 0.01 for Δon – post task) rather than the older adult group (n.s for Δpre - on task; n.s for Δon – post task). We further concluded that the oxyHb difference was present in the brain regions near the right dorsolateral prefrontal cortex. Taken together, these findings suggest that CIT2 (i.e., the melodic contour task in the target-like distraction) is an optimized task that could indicate the degree and type of age-related cognitive decline.

Attenuation of pressor response following intubation: Efficacy of nitro-glycerine lingual spray

BACKGROUND AND AIMS

The role of nitro-glycerine (NTG) lingual spray for attenuation of the hemodynamic response associated with intubation is not much investigated. We conducted this study to evaluate the efficacy of NTG lingual pump or pen spray in attenuation of intubation induced hemodynamic responses and to elucidate the optimum dose.

MATERIAL AND METHODS

In a prospective randomized controlled trial, 90 adult patients of ASA I, II, 18-60 year posted for elective general surgery under general anesthesia with intubation were randomly allocated to three groups as Group C (control) - receiving no NTG spray, Group N1 - receiving 1 NTG spray and Group N2 - receiving 2 NTG spray one minute before intubation. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate were recorded at baseline, just before intubation (i.e., 60 s just after induction and NTG spray), immediately after intubation, at 1, 2, 5 and 10 min after intubation.

RESULTS

Incidence of hypertension was significantly higher in Group C (60%, n = 18) as compared to Group N1 and N2 (10%, n = 3 each), P < 0.01. Mean value of SBP, DBP and MAP showed a significant rise as compared to baseline, following intubation in control group (15.31% in SBP, 12.12% in DBP, 17.77% in MAP) that persisted till 5 min, while no significant rise was observed in Group N1 and N2. There was a trend toward fall in blood pressure in Group N2 (4.95% fall in SBP, 4.72% fall in MAP) 1-min following spray, which was clinically insignificant. Mean value of SBP, DBP and MAP was significantly higher in Group C than in Group N1, which was in turn greater than Group N2 (Group C > N1> N2), P < 0.05. However, incidence of tachycardia was comparable in three groups (70% in group C, 63.33% in Group N1 and 67.77% in Group N2, P > 0.05).

CONCLUSIONS

We concluded that the NTG lingual spray in dose of 0.4 mg (1 spray) or 0.8 mg (2 sprays) was effective in attenuation of intubation induced hemodynamic response, in terms of preventing significant rise in SBP, DBP and MAP compared to control group.

Hemodynamic responses and energy expenditure during blood flow restriction exercise in obese population

PURPOSE

The study investigated the acute effects of different initial restrictive pressures (IRP; tightness of cuffs before inflation with air) on heart rate (HR), systolic (SBP) and diastolic blood pressure (DBP), rating of perceived exertion (RPE), respiratory exchange ratio (RER) and energy expenditure (EE) during constant-load upright cycling.

METHODS

In a within subject study design, 34 obese men (age = 24·3, n = 18) and women (age = 23·1, n = 16) completed three cycling sessions (two blood flow restriction and one control sessions). The cycling exercise was performed with an external load of 1kp at 50 rpm for 20 min with 1-min rest after the 10th-min. The blood flow restriction (BFR) cuffs were placed on the thigh of both legs during BFR sessions and IRP and IRP of ~40 or ~60 mmHg were applied in random order.

RESULTS

There were significant condition × time interactions for HR, SBP, RPE and RER and time × gender interactions for HR and SBP. There were also significant condition and time main effects for HR, SBP, RPE and RER (P<0·01) and a significant condition effect for EE (P<0·05).

CONCLUSION

The intensity of exercise with BFR was higher and affected by IRP, but the subjects perceived the effort as 'light'. Low-intensity cycling with BFR shows potential to reduce the time requirement per session to elicit greater EE while placing greater demands on the circulatory system.

Changes in hemodynamic responses in chronic stroke survivors do not affect fMRI signal detection in a block experimental design

The use of canonical functions to model BOLD-fMRI data in people post-stroke may lead to inaccurate descriptions of task-related brain activity. The purpose of this study was to determine whether the spatiotemporal profile of hemodynamic responses (HDRs) obtained from stroke survivors during an event-related experiment could be used to develop individualized HDR functions that would enhance BOLD-fMRI signal detection in block experiments. Our long term goal was to use this information to develop individualized HDR functions for stroke survivors that could be used to analyze brain activity associated with locomotor-like movements. We also aimed to examine the reproducibility of HDRs obtained across two scan sessions in order to determine whether data from a single event-related session could be used to analyze block data obtained in subsequent sessions. Results indicate that the spatiotemporal profile of HDRs measured with BOLD-fMRI in stroke survivors was not the same as that observed in individuals without stroke. We observed small between-group differences in the rates of rise and decline of HDRs that were more apparent in individuals with cortical as compared to subcortical stroke. There were no differences in the peak or time to peak of HDRs in people with and without stroke. Of interest, differences in HDRs were not as substantial as expected from previous reports and were not large enough to necessitate the use of individualized HDR functions to obtain valid measures of movement-related brain activity. We conclude that all strokes do not affect the spatiotemporal characteristics of HDRs in such a way as to produce inaccurate representations of brain activity as measured by BOLD-fMRI. However, care should be taken to identify individuals whose BOLD-fMRI data may not provide an accurate representation of underlying brain activation when canonical models are used. Examination of HDRs need not be done for each scan session, as our data suggest that the characteristics of HDRs in stroke survivors are reproducible across days.

A comparison of intraocular pressure and hemodynamic responses to insertion of laryngeal mask airway or endotracheal tube using anesthesia with propofol and remifentanil in cataract surgery

BACKGROUND

The aim of this study was to evaluate intraocular pressure (IOP) and hemodynamic responses following insertion of laryngeal mask airway (LMA) or endotracheal tube (ETT) after anesthesia induction with propofol and remifentanil in cataract surgery.

MATERIALS AND METHODS

In a randomized controlled study, 50 adults scheduled for elective cataract extraction procedure under general anesthesia were allocated to LMA insertion (n = 25) or ETT (n = 25) groups. IOP, systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured after insertion of the airway device every minute up to 5 min.

RESULTS

There were no significant differences between LMA and ETT groups in SBP, DBP, HR, and IOP immediately after airway instrumentation up to 5 min, except in 4th min in DBP, 2nd min in HR, and 5th min in IOP (7.9 ± 2.3 mmHg in LMA and 9.4 ± 2.5 mmHg in ETT group; P = 0.030). There was good surgeon satisfaction for providing acceptable surgical field in both groups (88% in LMA and 80% in ETT group; P = 0.702).

CONCLUSION

Propofol combined with remifentanil provides good and excellent conditions for insertion of LMA or ETT with minimal hemodynamic disturbances in cataract surgery. Considering LMA insertion is less traumatic than ETT, using LMA may be better than ETT for airway securing in these patients.

Hemodynamic responses and upper airway morbidity following tracheal intubation in patients with hypertension: conventional laryngoscopy versus an intubating laryngeal mask airway

OBJECTIVES

We compared hemodynamic responses and upper airway morbidity following tracheal intubation via conventional laryngoscopy or intubating laryngeal mask airway in hypertensive patients.

METHODS

Forty-two hypertensive patients received a conventional laryngoscopy or were intubated with a intubating laryngeal mask airway. Anesthesia was induced with propofol, fentanyl, and cis-atracurium. Measurements of systolic and diastolic blood pressures, heart rate, rate pressure product, and ST segment changes were made at baseline, preintubation, and every minute for the first 5 min following intubation. The number of intubation attempts, the duration of intubation, and airway complications were recorded.

RESULTS

The intubation time was shorter in the conventional laryngoscopy group than in the intubating laryngeal mask airway group (16.33 ± 10.8 vs. 43.04 ± 19.8 s, respectively) (p<0.001). The systolic and diastolic blood pressures in the intubating laryngeal mask airway group were higher than those in the conventional laryngoscopy group at 1 and 2 min following intubation (p<0.05). The rate pressure product values (heart rate x systolic blood pressure) at 1 and 2 min following intubation in the intubating laryngeal mask airway group (15970.90 ± 3750 and 13936.76 ± 2729, respectively) were higher than those in the conventional laryngoscopy group (13237.61 ± 3413 and 11937.52 ± 3160, respectively) (p<0.05). There were no differences in ST depression or elevation between the groups. The maximum ST changes compared with baseline values were not significant between the groups (conventional laryngoscopy group: 0.328 mm versus intubating laryngeal mask airway group: 0.357 mm; p = 0.754). The number and type of airway complications were similar between the groups.

CONCLUSION

The intense and repeated oropharyngeal and tracheal stimulation resulting from intubating laryngeal mask airway induces greater pressor responses than does stimulation resulting from conventional laryngoscopy in hypertensive patients. As ST changes and upper airway morbidity are similar between the two techniques, conventional laryngoscopy, which is rapid and safe to perform, may be preferred in hypertensive patients with normal airways.

Comparison of physiological and perceptual responses between continuous and intermittent cycling

The present study tested the hypothesis that the exercise protocol (continuous vs. intermittent) would affect the physiological response and the perception of effort during aquatic cycling. Each protocol was divided on four stages. Heart rate, arterial blood pressure, blood lactate concentration, central and peripheral rate of perceived exertion were collected in both protocols in aquatic cycling in 10 women (values are mean ± SD): age=32.8 ± 4.8 years; height=1.62 ± 0.05 cm; body mass=61.60 ± 5.19 kg; estimated body fat=27.13 ± 4.92%. Protocols were compared through two way ANOVA with Scheffé’s post-hoc test and the test of Mann- Whitney for rate of perceived exertion with α=0.05. No systematic and consistent differences in heart rate, arterial blood pressure, double product and blood lactate concentration were found between protocols. On the other hand, central rate of perceived exertion was significantly higher at stage four during continuous protocol compared with intermittent protocol (p=0.01), while the peripheral rate of perceived exertion presented higher values at stages three (p=0.02) and four (p=0.00) in the continuous protocol when compared to the results found in intermittent protocol. These findings suggest that although the aquatic cycling induces similar physiologic demands in both protocols, the rate of perceived exertion may vary according to the continuous vs. intermittent nature of the exercise.

Brain cortical mapping by simultaneous recording of functional near infrared spectroscopy and electroencephalograms from the whole brain during right median nerve stimulation

To investigate relationships between hemodynamic responses and neural activities in the somatosensory cortices, hemodynamic responses by near infrared spectroscopy (NIRS) and electroencephalograms (EEGs) were recorded simultaneously while subjects received electrical stimulation in the right median nerve. The statistical significance of the hemodynamic responses was evaluated by a general linear model (GLM) with the boxcar design matrix convoluted with Gaussian function. The resulting NIRS and EEGs data were stereotaxically superimposed on the reconstructed brain of each subject. The NIRS data indicated that changes in oxy-hemoglobin concentration increased at the contralateral primary somatosensory (SI) area; responses then spread to the more posterior and ipsilateral somatosensory areas. The EEG data indicated that positive somatosensory evoked potentials peaking at 22 ms latency (P22) were recorded from the contralateral SI area. Comparison of these two sets of data indicated that the distance between the dipoles of P22 and NIRS channels with maximum hemodynamic responses was less than 10 mm, and that the two topographical maps of hemodynamic responses and current source density of P22 were significantly correlated. Furthermore, when onset of the boxcar function was delayed 5-15 s (onset delay), hemodynamic responses in the bilateral parietal association cortices posterior to the SI were more strongly correlated to electrical stimulation. This suggests that GLM analysis with onset delay could reveal the temporal ordering of neural activation in the hierarchical somatosensory pathway, consistent with the neurophysiological data. The present results suggest that simultaneous NIRS and EEG recording is useful for correlating hemodynamic responses to neural activity.