Application value of dexmedetomidine in anesthesia for elderly patients undergoing radical colon cancer surgery

BACKGROUND Colon cancer presents a substantial risk to the well-being of elderly people worldwide.With advancements in medical technology,surgical treatment has become the primary approach for managing colon cancer patients.However,due to age-related physiological changes,especially a decline in cognitive function,older patients are more susceptible to the effects of surgery and anesthesia,increasing the relative risk of postoperative cognitive dysfunction(POCD).There-fore,in the surgical treatment of elderly patients with colon cancer,it is of pa-ramount importance to select an appropriate anesthetic approach to reduce the occurrence of POCD,protect brain function,and improve surgical success rates.METHODS One hundred and seventeen patients with colon cancer who underwent elective surgery under general anesthesia were selected and divided into two groups:A and B.Group A received Dex before anesthesia induction,and B group received an equivalent amount of normal saline.Changes in the mini-mental state exami-nation,regional cerebral oxygen saturation(rSO2),bispectral index,glucose uptake rate(GluER),lactate production rate(LacPR),serum S100βand neuron-specific enolase(NSE),POCD,and adverse anesthesia reactions were compared between the two groups.RESULTS Surgical duration,duration of anesthesia,and intraoperative blood loss were comparable between the two groups(P>0.05).The overall dosage of anesthetic drugs used in group A,including propofol and remifentanil,was significantly lower than that used in group B(P<0.05).Group A exhibited higher rSO2 values at the time of endotracheal intubation,30 min after the start of surgery,and immediately after extubation,higher GluER values and lower LacPR values at the time of endotra-cheal intubation,30 min after the start of surgery,immediately after extubation,and 5 min after extubation(P<0.05).Group A exhibited lower levels of serum S100βand NSE 24 h postoperatively and a lower incidence of cognitive dysfunction on the 1st and 5th postoperative days(P<0.05).CONCLUSION The use of Dex in elderly patients undergoing radical colon cancer surgery helps maintain rSO2 Levels and reduce cerebral metabolic levels and the incidence of anesthesia-and surgery-induced cognitive dysfunction.

Pulse oximetry in pediatric care:Balancing advantages and limitations

BACKGROUND Pulse oximetry has become a cornerstone technology in healthcare,providing non-invasive monitoring of oxygen saturation levels and pulse rate.Despite its widespread use,the technology has inherent limitations and challenges that must be addressed to ensure accurate and reliable patient care.AIM To comprehensively evaluate the advantages,limitations,and challenges of pulse oximetry in clinical practice,as well as to propose recommendations for optimizing its use.METHODS A systematic literature review was conducted to identify studies related to pulse oximetry and its applications in various clinical settings.Relevant articles were selected based on predefined inclusion and exclusion criteria,and data were synthesized to provide a comprehensive overview of the topic.RESULTS Pulse oximetry offers numerous advantages,including non-invasiveness,real-time feedback,portability,and costeffectiveness.However,several limitations and challenges were identified,including motion artifacts,poor peripheral perfusion,ambient light interference,and patient-specific factors such as skin pigmentation and hemoglobin variants.Recommendations for optimizing pulse oximetry use include technological advancements,education and training initiatives,quality assurance protocols,and interdisciplinary collaboration.CONCLUSION Pulse oximetry is crucial in modern healthcare,offering invaluable insights into patients’oxygenation status.Despite its limitations,pulse oximetry remains an indispensable tool for monitoring patients in diverse clinical settings.By implementing the recommendations outlined in this review,healthcare providers can enhance the effectiveness,accessibility,and safety of pulse oximetry monitoring,ultimately improving patient outcomes and quality of care.

Automobile Pollution and Risk of Impaired Lung Function and Oxygen Saturation among Vendors Near Road Traffic in Brazzaville, Congo

Context: Automobile pollution is becoming a potential threat to the cardiorespiratory health of the urban population of sub-Saharan Africa. The present study aims to evaluate the level of concentrations of fine particles (PM2.5 and PM10) near road traffic and the effects of exposure to automobile pollutants on pulmonary function and arteriolar blood oxygen saturation among sellers around road traffic. Materials and Methods: The study recruited 48 healthy people carrying out a sales activity near road traffic. PM2.5 and PM10 measurements were taken from 6 a.m. to 6 p.m. using a Temtop Airing-1000 portable particle detector. Spirometric measurements were taken in the morning and in the evening from a portable Spirobank G spirometer. Oxygen saturation measurements were also taken in the morning and evening using a Pulse oxymeter CMS50D pulse oxymeter. Results: Mean values of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and forced expiratory flow between 25% and 75% of forced vital capacity (FEF25 - 75) recorded in the evening were significantly lower than those obtained in the morning in the subjects of the total group and in the men. Only the mean values of PEF and FEF25 - 75 obtained in the evening were significantly lower than those recorded in the morning in women. Minimum PM2.5 values recorded near road traffic were negatively correlated with evening PEF in men, while maximum PM10 values were negatively correlated with evening PEF in women. The blood oxygen saturation recorded in the evening was significantly lower than that obtained in the morning. Conclusion: Short-term exposure to automobile pollutants has adverse effects on lung function and oxygen saturation in people carrying out a sales activity near road traffic.

Functional Imaging of Breast Tissue and Clinical Application

A novel approach to image hemoglobin concentration（△Dhb） and oxygen saturation （△Doxy） of breast tissue is presented. The scenograph of dual-wavelength （760 and 850 nm） near infrared lights through breast tissue is acquired by high sensitive charge coupled device （CCD） camera. The evaluation criterion of the difference of △Dhh and △Doxy between detected and referenced breast tissue can be obtained by a calculation formula without complicate caculation. This approach is applied to clinic detection in breast tissue. The ongoing clinical experiments indicate that malignant tumor usually exhibits characterize of ＂higher △Dhb and lower △Doxy＂, while benign lesion often shows ＂lower △Dhb and higher △Doxy＂ or other characters. So it is useful to assist the diagnosis of breast disease.

Retinal vessel oxygen saturation in healthy subjects and early branch retinal vein occlusion

AIM： To measure the retinal oxygen saturation in healthy subjects and early branch retinal vein occlusion（BRVO） in Chinese population.METHODS： The retinal vessel oxygen saturation of the healthy subjects and BRVO patients were measured by a noninvasive retinal oximeter（Oxymap ehf.,Reykjavik,Iceland）.RESULTS： The study included 22 patients with unilateral BRVO（mean age： 55.1±8.8y） in the study group and 91 healthy participants（mean age： 37.5±14.0y） in the control group.In the healthy individuals,mean arterial and venous oxygen saturation were significantly（P〈0.001）higher in the superior nasal quadrant（98.5%±10.1%and 57.3%±8.7%,respectively） than in the inferior nasal quadrant（94.2%±9.0% and 54.1%±9.6%,respectively）,followed by the superior temporal quadrant（89.1%±10.1%and 51.9%±8.9%,respectively） and the inferior temporal quadrant（86.4%±9.4% and 46.6%±9.6%,respectively）.In patients with ischemic BRVO,arterial oxymetric values were significantly higher and venous measurements significantly lower for the affected vessel（107.5%±9.7% and46.4%±14.2%,respectively） than the unaffected vessel in the same eye（99.2%±12.2% and 55.5%±7.9%,respectively）and as compared to the vessel in the unaffected fellow eye（93.1%±6.9% and 55.7%±6.8%）（P=0.005 and P=0.02,respectively）.In the patients with non-ischemic BRVO,mean venous oxygen saturation was lower in the affected vein（39.8%±12.2%） than in the unaffected vessels of the same eye（50.8%±10.5%） and in the fellow eye（58.21%±5.7%）（P=0.03）.Mean arterial oxygen saturation did not differ significantly（P=0.42） between all three groups.CONCLUSION： In patients with BRVO,the venous oxygen saturation in the affected vessels is decreased potentially due to decreased blood velocity and flow.Interestingly,thearterial oxygen saturation in eyes with ischemic BRVO is increased in the affected arteries.

Neuroprotection of hyperbaric oxygen therapy in sub-acute traumatic brain injury:not by immediately improving cerebral oxygen saturation and oxygen partial pressure

Although hyperbaric oxygen （HBO） therapy can promote the recovery of neural function in patients who have suffered traumatic brain injury （TBI）, the underlying mechanism is unclear. We hypothesized that hyperbaric oxygen treatment plays a neuroprotective role in TBI by increasing regional transcranial oxygen saturation （rSO2） and oxygen partial pressure （PaO2）. To test this idea, we compared two groups： a control group with 20 healthy people and a treatment group with 40 TBI patients. The 40 patients were given 100% oxygen of HBO for 90 minutes. Changes in rSO2 were measured. The controls were also examined for rSO2 and PaO2, but received no treatment, rSO2 levels in the patients did not differ significantly after treatment, but levels before and after treatment were significantly lower than those in the control group. PaO2 levels were significantly decreased after the 30-minute HBO treatment. Our findings suggest that there is a disorder of oxygen metabolism in patients with sub-acute TBI. HBO does not immediately affect cerebral oxygen metabolism, and the underlying mechanism still needs to be studied in depth.

A specific objective supplemental factor in evaluating acute mountain sickness: ΔHR in combination with SaO_2

Background: So far, there have been no measurements confirmed useful in diagnosing acute mountain sickness(AMS). The aim of this study was to determine the role of heart rate(HR) difference(ΔHR) and oxygen saturation(Sa O2) as objective risk factors in aiding the diagnosis of AMS.Methods: A total of 1,019 participants were assigned to either the acute exposure group(AEG): from 500 m to 3,700 m by flight within 2.5 hours(n=752); or the pre-acclimatization group(PAG): ascended to 4,400 m from 3,650 m within three hours by car after adapting 33 days at 3,650m(n=267). The questionnaires or measurements of resting Sa O2 and HR were completed between 18 and 24 hours before departure and after arrival.Results: Incidence of AMS was 61.3%(461) in AEG, with 46.1%(347) mild cases and 15.2%(114) severe cases. In PAG, the incidence was 38.9%(104), with 30.7%(82) mild cases and 8.2%(22) severe cases. The AMS subjects showed a significant increase in HR and a decrease in Sa O2 levels compared with the non-AMS subjects in both groups. ΔHR and post-exposure Sa O2 were significantly correlated with the Lake Louise Score(LLS) in both groups. Stepwise logistic regression analysis revealed the ΔHR >25 and Sa O2 <88% in AEG as well as ΔHR >15 and Sa O2 <86% in PAG to be independent risk factors of AMS. Combining these two measurements could specifically indicate participants with AMS, which showed a positive predictive value of 89% and specificity of 97% in AEG as well as 85% and 98% in PAG.Conclusion:ΔHR or Sa O2, as objective measurements, correlate with AMS. Combination of these two measurements may be useful as an additional specific and objective factor to further confirm the diagnosis of AMS.

Effects of white noise on procedural pain-related cortical response and pain score in neonates:A randomized controlled trial

Objectives To evaluate the effects of white noise on pain-related cortical response,pain score,and behavioral and physiological parameters in neonates with procedural pain.Methods A double-blind,randomized controlled trial was conducted.Sixty-six neonates from the Neonatal Intensive Care Unit in a university-affiliated general hospital were randomly assigned to listen to white noise at 50 dB(experimental group)or 0 dB(control group)2 min before radial artery blood sampling and continued until 5 min after needle withdrawal.Pain-related cortical response was measured by regional cerebral oxygen saturation(rScO_(2))monitored with near-infrared spectroscopy,and facial expressions and physiological parameters were recorded by two video cameras.Two assessors scored the Premature Infant Pain Profile-Revised(PIPP-R)independently when viewing the videos.Primary outcomes were pain score and rScO_(2)during arterial puncture and 5 min after needle withdrawal.Secondary outcomes were pulse oximetric oxygen saturation(SpO_(2))and heart rate(HR)during arterial puncture,and duration of painful expressions.The study was registered at the Chinese Clinical Trial Registry(ChiCTR2200055571).Results Sixty neonates(experimental group,n=29;control group,n=31)were included in the final analysis.The maximum PIPP-R score in the experimental and control groups was 12.00(9.50,13.00),12.50(10.50,13.75),respectively(median difference−0.5,95%CI−2.0 to 0.5),and minimum rScO_(2)was(61.22±3.07)%,(61.32±2.79)%,respectively(mean difference−0.325,95%CI−1.382 to 0.732),without significant differences.During arterial puncture,the mean rScO_(2),HR,and SpO_(2)did not differ between groups.After needle withdrawal,the trends for rScO_(2),PIPP-R score,and facial expression returning to baseline were different between the two groups without statistical significance.Conclusion The white noise intervention did not show beneficial effects on pain-related cortical response as well as pain score,behavioral and physiological parameters in neonates with procedural pain.

Effects of Integrative Chinese and Western Medicine on Arterial Oxygen Saturation in Patients with Severe Acute Respiratory Syndrome

Objective: To evaluate the effects of treatment of integrative Chinese and Western medicine (ICWM) on arterial oxygen saturation (SaO2) in patients with severe acute respiratory syndrome (SARS). Methods:The non-randomized, controlled trial was conducted on 447 SARS patients treated synchronously with western conventional treatment (WM group, n = 171) alone and ICWM (ICWM group, n = 276). The changes of the cases with normal level (≥95% ) or abnormal level (<95% ) SaO2 were observed dynamically. Results: In the 3rd-14th day of the therapeutic course, the percentage of patients with normal SaO2 in the ICWM group was higher than that in the WM group (OR = 0.5178, P = 0.0038), and this tendency was more evident in patients of the severe type (OR = 0. 18, P = 0. 0001). However, the statistical significance of difference was only shown in patients for whom the ICWM treatment started in the early period after the onset (≤7 days after it, OR = 0.3803, P = 0.006), but not shown in those who received ICWM treatment later in the mid-late period of SARS ( P>0. 05). Conclusion: ICWM treatment, particularly when it is used for intervention in the early stage, is beneficial for maintaining normal SaO2 in SARS patients.

Effects of oxygen concentration and flow rate on cognitive ability and physiological responses in the elderly

The supply of highly concentrated oxygen positively affects cognitive processing in normal young adults. However, there have been few reports on changes in cognitive ability in elderly subjects following highly concentrated oxygen administration. This study investigated changes in cognitive ability, blood oxygen saturation （%）, and heart rate （beats/min） in normal elderly subjects at three different levels of oxygen [21% （1 L/min）, 93% （1 L/min）, and 93% （5 L/min）] administered during a 1-back task. Eight elderly male （75.3 ＋ 4.3 years old） and 10 female （71.1 ＋ 3.9 years old） subjects, who were normal in cognitive ability as shown by a score of more than 24 points in the Mini-Mental State Examination-Korea, participated in the experiment. The experiment consisted of an adaptation phase after the start of oxygen administration （3 minutes）, a control phase to obtain stable baseline measurements of heart rate and blood oxygen saturation before the task （2 minutes） and a task phase during which the 1-back task was performed （2 minutes）. Three levels of oxygen were administered throughout the three phases （7 minutes）. Blood oxygen saturation and heart rate were measured during each phase. Our results show that blood oxygen saturation increased, heart rate decreased, and response time in the 1-back task decreased as the concentration and amount of administered oxygen increased. This shows that administration of sufficient oxygen for optimal cognitive functioning increases blood oxygen saturation and decreases heart rate.

Effect of Hemodilution on Fluctuation of Cerebral Oxygen Saturation during Cardiopulmonary Bypass in Children with Cyanotic Congenital Heart Disease

Background:In patients with cyanotic congenital heart disease(CHD),cerebral oxygenation may be maintained by elevations in hematocrit(Hct).Hemodilution accompanying cardiopulmonary bypass(CPB),however,can disrupt cerebral oxygen balance,leading to fluctuations in cerebral oxygen saturation(ScO_(2)).The present study investigated the effects of Hct changes on the fluctuation of ScO_(2)during CPB in cyanotic CHD using performance measurement(PM).Methods:Children with CHD(51 acyanotic and 46 cyanotic)who had undergone cardiac surgery using CPB were enrolled.Median performance error(MDPE),median absolute performance error(MDAPE),and wobble parameters of ScO_(2)were calculated before(reference value),during,and after CPB.Correlations of PM parameters with Hct and reductions in Hct(ΔHct)were also evaluated.Results:Before CPB,patients with cyanotic CHD had lower MDPE and larger wobble than those with acyanotic CHD,although mean ScO_(2)did not differ significantly between the two groups.During CPB,ScO_(2)of acyanotic CHD increased asΔHct increased,but PM variables were not associated withΔHct.In cyanotic CHD,MDPE(r=−0.324,p=0.032)and MDAPE(r=0.339,p=0.024)correlated significantly withΔHct during CPB.After CPB,MDPE(r=0.574,p=0.025)and MDAPE(r=−0.543,p=0.036)were significantly correlated with Hct in children with cyanotic CHD who underwent palliative surgery.Conclusion:Therefore,ScO_(2)fluctuation during CPB in children with cyanotic CHD may be affected by the decrease in Hct,suggesting that excessive hemodilution can negatively influence the maintenance of cerebral oxygenation in these patients.

Multispectral imaging of acute wound tissue oxygenation

This paper investigates the appropriate range of values for the transcutaneous blood oxygen saturation(StO2)of granulating tissues and the surrounding tissue that can ensure timely wound recovery.This work has used a multispectral imaging system to collect wound images at wave-lengths ranging between 520 nm and 600 nm with a resolution of 10 nm.As part of this research,a pilot study was conducted on three injured individuals with superfcial wounds of different wound ages at different skin locations.The S_(t)O_(2)value predicted for the examined wounds using the Extended Modified Lambert-Beer model revealed a mean S_(t)O_(2)of 61±10.3%compared to 41.6±6.2%at the surrounding tissues,and 50.1±1.53%for control sites.These preliminary results contribute to the existing knowledge on the possible range and variation of wound bed S_(t)O_(2)that are to be used as indicators of the functioning of the vasomotion system and wound health.This study has concluded that a high S_(t)O_(2)of approximately 60%and a large fuctuation in this value should precede a good progression in wound healing.

Potential benefits of Qi Gong meditation in quantifiable physiology: A five-year longitudinal observation

Objective: Qi Gong is a mind-and-body intervention to improve health and relieve disease conditions,which has been practiced for thousands of years. Lack of quantitative measures to monitor the quality and progress of Qi Gong practice has hindered the high-quality study to evaluate its health benefits.Methods: To develop such quantitative measures, vital sign changes in Qi Gong meditation practice of a single individual were monitored for 5 years by wearable devices.Results: This retrospective and exploratory analysis revealed significant changes in blood oxygen saturation, pulse rate, respiration rate, and perfusion index in response to Qi Gong practice and physiological adaptation to its long-term training. Among the physiological changes in vital signs, a physiological state with a significant 2-fold increase in pulse-respiration rate ratio was detected during Qi Gong meditation while the ratios were maintained at 4 under resting, sleeping, and mild cycling conditions.Conclusion: This is an inaugural report of a five-year longitudinal observation of this kind. Once validated in a well-designed cohort study, these non-invasive and easily obtained vital signs may be used as biomarkers to assess the adherence to breathing control during Qi Gong practice and can be applied to quantify the quality of Qi Gong practice in clinical trials with Qi Gong intervention.

Screening Coarctation of Aorta with Clinical and Echocardiographic Profiles in Infants:A Pilot Study

Aim:To determine the profiles of clinical features including four-limb blood pressure(BP),saturations of peripheral oxygen(SpO2),and echocardiographic features in infants with coarctation of aorta(CoA)to facilitate congenital heart diseases screening.Methods:The charts of infants with CoA were retrospectively reviewed.All in-hospital infants suspected of congenital heart diseases by clinical teams were prospectively measured of four limbs BPs and SpO2 in a regional cardiac transferring center during 2013 and 2019.Echocardiography as a gold standard test was followed within 2 days after suspicion.All infants were divided into non-significant CoA group or significant CoA group based on the difference of BPs between right arm and lower limbs.Predictors of nonsignificant CoA were determined with multivariable logistic regression.Results:One hundred thirty-three infants with CoA were identified.The BPs on upper limbs were higher than those on lower limbs(P=0.001).No statistical difference in SpO2 was found between four limbs.Fifty-three(39.8%)infants presented with significant CoA.Thirty-four infants presented with low SpO2 and 26 of 34 presented with non-significant CoA.Small ascending aorta diameter[0.070(95%CI:0.005–0.136),P=0.036]was an independent risk factors for non-significant CoA.Eighteen(13.5%)infants with CoA didn’t present with any of the BP difference,low SpO2,murmur,or weak femoral pulse.Conclusion:Less than half of the infants with CoA presented with a significant BP difference.Another one fifth presented with low SpO2.Small ascending aorta diameter was an independent factor for non-significant CoA.

Changes and significance of retinal blood oxygen saturation and oxidative stress indexes in patients with diabetic retinopathy

BACKGROUND Diabetic retinopathy(DR)is a diabetic complication that can severely affect the patients’vision,eventually leading to blindness.DR is the most important manifestation of diabetic micro-vasculopathy and is mainly related to the course of diabetes and the degree of blood glucose control,while the age of diabetes onset,sex,and type of diabetes have little influence on it.AIM To explore the changes in blood oxygen saturation and oxidative stress indices of retinal vessels in patients with DR.METHODS In total,94 patients(94 eyes)with DR(DR group)diagnosed at Jianyang people’s Hospital between March 2019 and June 2020,and 100 volunteers(100 eyes)(control group)without eye diseases,were included in this study.Arterial and venous blood oxygen saturation,retinal arteriovenous vessel diameter,and serum oxidative stress indicators in the two groups were compared.Based on the stage of the disease,the DR group was divided into the simple DR and proliferative DR groups for stratified analysis.RESULTS The oxygen saturation of the retinal vessels in the DR group was significantly higher than that in the control group(P<0.05).The retinal vessel diameters between the DR and control groups were not significantly different.The serum malondialdehyde(MDA)and 8-hydroxydehydroguanosine(8-OHdG)levels in the DR group were significantly higher than those in the control group(P<0.05).The serum superoxide dismutase(SOD)and reduced glutathione(GSH)levels in the DR group were significantly lower than those in the control group (P < 0.05). The oxygensaturation of the retinal vessels in the patients with proliferative DR was significantly higher thanthat in the patients with simple DR (P < 0.05). The retinal vessel diameter in patients with proliferativeDR was not significantly different from that of patients with simple DR (P > 0.05). SerumMDA and 8-OHdG levels in patients with proliferative DR were significantly higher than those inpatients with simple DR (P < 0.05). Serum SOD and GSH levels in patients with proliferative DRwere significantly lower than those in patients with simple DR (P < 0.05).CONCLUSIONIncreased blood oxygen saturation of retinal arteries and veins and increased oxidative stressdamage in patients with DR may be associated with decreased retinal capillary permeability andarterial oxygen dispersion, possibly reflecting the patient’s condition.

Effects of various anesthetic techniques and PaCO_2 levels on cerebral oxygen balance in neurosurgical patients

Objective: To assess the effects of various anesthetic techniques and PaCO2 levels on cerebral oxygen supply/consumption balance during craniotomy for removal of tumors, and to explore an anesthetic technique for neurosur-gery and an appropriate degree of PaCO2 during neuroanesthesia. Methods: One hundred and fourteen patients with supratentorial tumors for elective craniotomy, ASA grade I - II , were randomly allocated to six groups. Patients were anesthetized with continuous intravenous infusion of 2% procaine 1. 0 mg · kg-1 · min-1 in Group I , inhalation of 1. 0% - 1. 5% isoflurane in Group II , and infusion of 2% procaine 0. 5 mg·kg · min-1 combined with inhalation of 0.5% -0.7% isoflurane in Group III during the period of study. The end-tidal pressure of CO2(PET CO2 ) was maintained at 4.0 kPa in these 3 groups. In Group IV, V and VI, the anesthetic technique was the same as that in Group I but the PETCO2 was adjusted to 3. 5, 4. 0 and 4. 5 kPa respectively for 60 min during which the study was performed. The radial arterial and retrograde jugular venous blood samples were obtained at the onset and the end of this study for determining jugular venous bulb oxygen saturation ( SjvO2 ) , arteriovenous oxygen content difference (AVDO2) and cerebral extraction of oxygen (CEO2). Results: In Group I and I SjvO2, AVDO2 and CEO2 remained stable. Although SjvO2 kept constant, AVDO2 and CEO2 decreased significantly (P <0. 05) in Group II. Moreover, AVDO2 and CEO2 in Group II were significantly lower than those of Group III (P<0. 05). In Group IV, 60 min after hyperventilation, SjvO2 and jugular venous oxygen content ( CjvO2 ) decreased markedly (P < 0. 01 ) while CEO2 increased significantly ( P <0.01) . In addition, SjvO2, CjvO2 and CEO2 in Group IV were significantly different from the corresponding parameters in Group V and Group VI (P <0. 05) . In view of sustained excessive hyperventilation, SjvO2 was less than 50% in 37.5% patients of Group IV. Conclusion: Anesthesia with intravenous infusion of procaine combined with isoflurane inhalation proved to be more suitable for neurosurgery than procaine intravenous anesthesia or isoflurane inhalation anesthesia alone. PaCO2 at 4.0 -4. 5 kPa in patients undergoing craniocerebral surgery during neuroanesthesia would be beneficial in both decreasing ICP and maintaining cerebral oxygen supply/consumption balance.

Clinical application of vascular occlusion test based on tissue oxygen saturation monitoring

The vascular occlusion test (VOT) is an experiment that simulates the process of distal ischemia-reperfusion of tissue based on the monitoring of tissue oxygen saturation (StO2) to obtain VOT parameters related to StO2 changes to evaluate microcirculation function of the measured muscle tissue. VOT has the advantages of real-time, noninvasive and continuous, and is widely used to evaluate the functional status of peripheral microcirculation and the relationship between microcirculation changes and prognosis of patients. In clinical work, doctors mainly focus on hemodynamics of patients, while microcirculation function is often neglected due to the lack of real-time monitoring methods, which may lead to severe poor prognosis of patients, especially patients with critical illness. This paper focuses on the clinical application of vascular occlusion test based on tissue oxygen saturation monitoring.

Factors associating with oxygenation of lower-limb muscle tissue in hemodialysis patients

AIM To evaluate the lower-limb muscle oxygenation in hemodialysis(HD) patients and identify the factors associating with muscle oxygenation.METHODS Sixty-seven HD patients(53 men and 14 women; mean age, 67.1 ± 1.2 years; mean HD duration, 5.6 ± 0.9 years) were recruited. In addition, 15 healthy individuals(nine men and six women; mean age, 38.2 ± 4.6 years) were recruited as the control group. Lower-limb muscle regional saturation of oxygen(rS O_2) was monitored on the lateral side of the gastrocnemius muscle before HD using an INVOS 5100C(Covidien Japan, Tokyo, Japan), which utilizes near-infrared spectroscopy. Here, we evaluated the association between lower-limb muscle rS O_2 and clinical parameters.RESULTS The r SO_2 values were significantly lower in patients undergoing HD than in healthy individuals(50.0%± 1.7% vs 76.8% ± 2.5%, P < 0.001). Lower-limb muscle r SO_2 showed significant positive correlations with diastolic blood pressure, blood urea nitrogen concentration, serum creatinine concentration, serum potassium concentration, serum inorganic phosphate concentration, and serum albumin concentration as well as negative correlation with HD duration. We conducted a multiple linear regression analysis using parameters that were significantly correlated with the lower-limb muscle r SO_2 in a simple linear regression analysis. Multiple regression analysis demonstrated that lowerlimb muscle r SO_2 was independently associated with serum inorganic phosphate(standardized coefficient: 0.27) and serum albumin concentrations(standardized coefficient: 0.24). In addition, there were no differences in lower-limb muscle r SO_2 between diabetic and nondiabetic HD patients. This study has several limitations. Firstly, its sample size was relatively small. Secondly, we could not evaluate the association between lowerlimb muscle r SO_2 and calculated nutritional markers, including normalized protein catabolic rate and body mass index, anthropometric measurements representing nutritional status, and the severity of protein-energy wasting. Finally, we did not routinely examine the arterial vascular status of HD patients without symptoms of peripheral artery disease. As such, it is possible that some HD patients with subclinical peripheral artery disease may have been included in this study.CONCLUSION In HD patients, the oxygenation of lower-limb muscle tissue was associated with serum inorganic phosphate and albumin concentrations, both of which represent nutritional status.

Systematic Review and Meta-Analysis of the Palatal Surgeries in the Treatment of Obstructive Sleep Apnea

Background: This paper aims to examine published articles between January 2008 and January 2019 on the different palatal surgeries performed on OSA patients and the treatment outcomes, which in turn will be used to determine the effectiveness of various palatal surgical techniques in treating OSAS and the most effective of the palatal surgical techniques in treating OSAS. Patients and Methods: The current review followed the guidelines of preferred reporting items for systematic reviews and meta-analysis statement 2009 (PRISMA). The quality of relevant studies was assessed using NIH quality assessment tool for observational cohort and cross-sectional studies as well as NIH tool for quality assessment for case series studies. Results: Meta-analyses of relevant studies showed that the surgical technique that achieved the best reduction on AHI (Apnea/Hypopnea Index) was the lateral pharyngoplasty followed by the Anterior Palatoplasty, with a significant mean reduction of [(SMD = −0.848, 95% CI (−1.209 - −0.487), p-value < 0.001) and (SMD = −0.864, 95% CI (−1.234 - −0.494), p-value < 0.001), respectively]. The technique responsible for the best improvement in Epworth Sleepiness Score (ESS) was the Relocation Pharyngoplasty, with a significant mean reduction of [SMD = −0.998, 95% CI (−1.253 - −0.743), p-value < 0.001]. Minimal O2 saturation level improved most with the Expansion Sphincter Pharyngoplasty, with a significant mean reduction of [SMD = 1.011, 95% CI (0.581 - 1.440), p-value < 0.001]. The surgical procedure that results in the best post-operative Visual Analogue Scale (VAS) was Z-Palatoplasty, with a significant mean reduction of [SMD = −1.551, 95% CI (−2.049 - −1.052), p-value < 0.001]. Soft palate length changes with a significant mean reduction of [SMD = −2.219, 95% CI (−2.730 - −1.708), p-value < 0.001]. Finally, meta-analyses of relevant studies showed that expansion sphincter pharyngoplasty achieved the overall highest success rate [event rate = 77%, 95% CI (65.4% - 85.5%), p-value < 0.001]. Conclusion: The best procedure for treating OSA varies from patient to patient and there is no universal cure-all. Careful patient selection and pre-operative evaluation are mandatory.

The Feasibility of Flat, Portable and Wireless Device for Non-Invasive Peripheral Oxygenation Measurement over the Entire Body

Peripheral oxygenation level (SpO2) can provide vital information on body functions. Continuous monitoring facilitates effective diagnosis and treatment and can even be lifesaving. Clinical device monitor SpO2 using a clip, and measure light transmission through the tissue. This method limits the body locations of the clip’s placement and is sensitive to body movement, which hampers continuous SpO2 monitoring during wakefulness or sleep, thus decreasing its usability in clinics and its accessibility in homecare usage. We developed a portable, wireless, flat and low cost prototype for continuous monitoring of SpO2 that overcomes those limitations. The prototype enables convenient measurement in larger variety of body locations by spectrophotometric measurements of changes in the optical reflectance unlike other device that measure absorption through the tissue. The original design and signal processing enable reliable signal acquisition, synchronization and control. An Android’s application was developed to provide a user friendly interface for results display on smartphones. The prototype’s measurements were compared to commercial device that simultaneously measured heart rate frequency, transcutaneous oxygen tension (tcPO2) and SpO2. The prototype’s measurements accurately reflected changes caused by blood pulses, were correlated to the heart rate, and were sensitive to changes in oxygen saturation. Excellent real time behavior and synchronization were demonstrated between the hardware and smartphone software. Our prototype thus enables convenient SpO2 measurement over the entire body, while maintaining accuracy comparable to commercial device. Its smartphone application enables accessible and understandable results display to patients, care-givers and healthcare professionals. The application’s display and alert calibration flexibility facilitates the prototype’s usage in changing medical requirements and for various disease and conditions. A device based on this prototype can monitor continuously and accurately patients’ SpO2 without limiting their everyday activities or disturbing their sleep and can thus significantly im-prove their medical care in both clinics and home.