Significant Changes In Oxygen Saturation Research Articles

126-LB: Evaluation of the Efficacy of the Therapeutic Agent Cytoreg in Patients with Diabetic Foot: A Clinical Humanitarian Protocol

Diabetic foot wound complications, including bacterial infections, ulcerations, and gangrene, are a major cause of hospitalizations and account for 85% of diabetic amputations. The investigational therapeutic agent Cytoreg®, an aqueous mixture of hydrofluoric, hydrochloric, sulfuric, phosphoric, phosphoric, citric, and oxalic acids, was recently shown to increase arterial oxygen levels in an orally administered Wistar rat model. It previously demonstrated bactericidal effect. Under a compassionate use protocol, we tested oral and topical treatment with diluted Cytoreg in patients with diabetic foot ulcers in a 30-day study in Venezuela. The total study population was ten patients under informed consent. On average, all patients received oral Cytoreg daily for 30 days. Five patients received oral Cytoreg plus topical wound cleansing with Cytoreg in isotonic saline. In addition to standard clinical observations, wound healing was monitored using the St. Elian’s checklist system. Four of five patients in the oral plus topical group had complete closure of their wounds after thirty days. Two of the patients in the oral group had complete wound closure. There was no significant change in oxygen saturation in the affected tissues, nor in insulin and glycemia levels. However, there were significant increases in arterial hemoglobin and arterial oxygen-pO2- were observed. Significant decreases HbA1c, aspartate aminotransferase, glutamic-pyruvic transaminase, creatinine, and urea levels were also observed. The overall results are encouraging and justify an expanded study in the treatment of diabetic foot wounds. Disclosure D. A. Carrillo: Research Support; Self; Cytorex Biosciences Inc. K. Villasana: None. G. Torres: Research Support; Self; Cytorex Bioscience Inc. L. J. Pozo: None. W. J. Jimenez: Board Member; Self; Cytorex Biosciences Inc. W. E. Bauta: Advisory Panel; Self; Cytorex Biosciences, Vascular Perfusion Solutions, Employee; Self; bioAffinity Technologies. L. Dugarte: None.

Effects of N95 Mask Use on Pulmonary Function in Children

To assess whether use of an N95 mask by children is associated with episodes of desaturation or respiratory distress. Twenty-two healthy children were assigned at random to 1 of 2 groups: one group wearing N95 masks without an exhalation valve and the other group wearing N95 masks with an exhalation valve. We tracked changes in partial pressure of end-tidal carbon dioxide (PETCO2), oxygen saturation, pulse rate, and respiratory rate over 72minutes of mask use. All subjects were monitored every 15minutes, the first 30minutes while not wearing a mask and the next 30minutes while wearing a mask. They then performed a 12-minute walking test. The children did not experience a statistically significant change in oxygen saturation or pulse rate during the study. There were significant increases in respiratory rate and PETCO2 in the children wearing an N95 mask without an exhalation valve, whereas these increases were seen in the children wearing a mask with an exhalation valve only after the walking test. The use of an N95 mask could potentially cause breathing difficulties in children if the mask does not have an exhalation valve, particularly during a physical activity. We believe that wearing a surgical mask may be more appropriate for children.

Sighs during sleep in multiple system atrophy

Sighs are physiological phenomena and may occasionally occur during sleep in healthy young adults. Although inspiratory sighs are considered a diagnostic red flag for the parkinsonian form of multiple system atrophy (MSA), its frequency and characteristics are unclear. We aimed to define sigh frequency during sleep recordings in patients with MSA compared to Parkinson's disease (PD) patients, as well as evaluate possible associated breathing disorders or autonomic changes. We analyzed 9 polysomnography's from patients with MSA and 9 from matched PD patients. The proportion of MSA patients (both MSA-P and MSA-C) with sleep-related sighs was significantly higher than that of PD patients, and these occurred predominantly in stages N1 and N2. The median sigh index in sleep and wakefulness were also significantly higher in MSA, although with a significant inter-subject variability. Higher sigh indexes were not associated to other breathing disturbances or with longer disease duration. In MSA, 12% of sighs were associated with oxygen desaturation, while none of the events in PD patients presented with significant changes in oxygen saturation. Respiratory events followed 45% of sighs in MSA, predominantly central sleep apneas, and 29% of sighs in PD, predominantly hypopneas. Our data suggests that high sigh frequencies during sleep should also be considered a red flag for MSA, and future studies should aim to determine whether increased sighing frequency during sleep is specific for this disorder.

Increased Activity Tolerance based on Hemodynamic Status in Patients Coronary Heart Disease After Physical Rehabilitation of Phase I (Inpatient)

Coronary Heart Disease (CHD) is caused by atheroma/plaque attached to the endothelial lining of the coronary arteries which causes blockages in oxygen and nutrient distribution to the tissues. This condition causes CHD patients to experience deficits in functional capacities, such as self-care ability, incapacity for performing the activity of daily living and also social activities. This study aims to analyze activity tolerance based on hemodynamic status (respiration, blood pressure, pulse frequency, oxygen saturation) in CHD patients after phase 1 physical rehabilitation (inpatient). The research method is quasy experiment one group pre-post-test research method. The results of data analysis using the Friedman test found that there was a significant effect on respiration on days 2, 3, systolic blood pressure on days 1 and 3, no significant effect on diastolic blood pressure, significant changes in oxygen saturation on days 1, 2, and 3, changes in pulse frequency on days 1 and 3.

EFFECTS OF RESISTANCE EXERCISE TRAINING ON ENDOTHELIAL FUNCTION AND MUSCLE PERFUSION IN OLDER ADULTS WITH DIABETES

BACKGROUND: Sarcopenia contributes to frailty, disability, and dependence in older adults, and is accelerated by Type 2 Diabetes Mellitus (T2DM). In addition to its direct role in increasing muscle mass, progressive resistance exercise training (PRET) may also reduce sarcopenia by improving endothelial function and muscle perfusion. METHODS: Fifteen older adults with uncomplicated and well-controlled T2DM participated in a PRET program 3 times weekly for 3 months. Prior to and immediately following the intervention, flow-mediated dilation testing was performed to assess large vessel endothelial function via ultrasound and muscle perfusion via near-infrared spectroscopy (NIRS). RESULTS: Preliminary ultrasound data from 9 subjects show a significant increase (5.21% to 8.73%, p=0.0448) in percent flow mediated dilation (%FMD), suggesting a modest improvement in endothelial function after 3 months’ PRET. Preliminary NIRS data from 7 subjects showed no significant changes in oxygen saturation or reperfusion rates as a result of the intervention. CONCLUSION: Our preliminary data indicate that, in older adults with T2DM, 3 months’ PRET is associated with modestly improved endothelial function in large vessels (as demonstrated by a significant increase in %FMD), but does not appear to be associated with improvements in muscle perfusion

Six minutes walk test outcome measures in children

Background: There are limited numbers of studies on 6 MWT in school going children in India. Objectives were to know gender wise outcome measurements for 6 MWT and its correlation with various anthropometric parameters, to make comparison of results between children of various socio-economic groups. Methods: After a randomized selection of schools a total of 500 children belonging to different socioeconomic status and studying in Government and Private Schools aged between 7-12 years were enrolled in the study. At the start, anthropometric measurements and baseline parameters like HR, BP, SPO2, PEFR, level of dyspnea were recorded and then children were made to walk for 6 minutes. After the walk changes in these parameters were taken as outcome measures.Results: The Mean distance walked in 6 minute was 609 ± 166 m. Boys covered more distance than girls. Heart rate increased from a baseline of 82.73 ± 1.63 to a maximum of 104.32 ± 3.11; heart rate recovery occurred (>90%) at 5 min in both the genders. SBP (systolic blood pressure) increased from baseline 109 ± 2.38 to maximum of 121.86 ± 1.75 at the end of the test, with no significant increase in DBP. The 6 minute walk distance correlated well with higher level of dyspnea. No significant change in oxygen saturation was observed during the test.Conclusions: The study provides data on normal values of 6MWT in healthy children, which may help to evaluate functional capacity and thus predict the morbidity risk in future and to know the effects of therapeutic interventions in the diseased children.

The effect of pars plana vitrectomy and nuclear cataract on oxygen saturation in retinal vessels, diabetic and non-diabetic patients compared.

To determine the effect of pars plana vitrectomy (PPV) on oxygen saturation in retinal vessels in patients with diabetes and non-diabetes after a 1-year follow-up. This was a prospective consecutive interventional case series in 82 eyes in 82 patients. The sample consisted of 25 patients with non-proliferative diabetic retinopathy with macular oedema based on vitreoretinal traction or epiretinal membrane (ERM) and 57 non-diabetic patients with macular hole and ERM. Automatic retinal oximetry (Oxymap Inc.) was used on all patients 24 hr prior to PPV, and it was also used 7 and 52 weeks after PPV (classic 20G or sutureless 23G). We analysed the data according to subgroup diagnosis and lens status. Arterial saturation increased significantly from 96.4 ± 2.9% at baseline to 96.6 ± 3.4% at week 7 and 97.3 ± 3.4% at week 52 (p < 0.0001; Friedman test). Vein saturation also increased significantly from 63.5 ± 7.9% at baseline to 66.1 ± 7.7% and 67.0 ± 7.2% at weeks 7 and 52 (p < 0.0001; Friedman test). The value of the arteriovenous (A-V) difference decreased significantly after vitrectomy from 32.8 ± 7.5% at baseline to 30.5 ± 7.5% and 30.3 ± 7.0% at weeks 7 and 52 (p < 0.0001; Friedman test). The subgroup analysis revealed that in patients with diabetes, there were no statistically significant changes in oxygen saturation in blood vessels or in the A-V difference after PPV. After vitrectomy, retinal vessel diameter reduced by about 3.5% in both groups of patients. Further, the analysis revealed that opacification of the lens leads to a decrease in oxygen saturation in contrast to a clear lens and pseudophakic IOLs. Oxygen saturation is higher in the retinal veins and arteries after PPV in patients with non-diabetes, and this lasts for at least 52 weeks. In contrast, in patients with diabetes, there is no increase in oxygen saturation in the retinal vessels after vitrectomy. After vitrectomy, retinal vessel diameter reduced in both groups of patients. Further, the nuclear cataract progression has substantial effect on oximetry results. Patients with nuclear cataract exhibited an increase in saturation in both arteries and veins, but the A-V difference remained the same.

Metabolic load during strength training or NMES in individuals with COPD: results from the DICES trial.

BackgroundStrength training and neuromuscular electrical stimulation (NMES) are effective training modalities for improving muscle function, exercise performance and health status in individuals with COPD. The aim of the present study was to analyze the metabolic load of these training modalities at baseline, half-way, and at the end of an eight-week interdisciplinary pulmonary rehabilitation program in a subgroup of individuals with COPD of the DICES trial.MethodsOf 24 individuals with COPD (FEV1: 34 ± 2% predicted, men: 58%, age: 66 (61–68) years), peak oxygen uptake (VO2), peak minute ventilation (VE), heart rate, oxygen saturation and symptom scores were assessed during HF-NMES (75 Hz), LF-NMES (15 Hz) and strength training at three moments during their pulmonary rehabilitation program.ResultsIntervention-related peak VO2 did not change over time during HF-NMES, LF-NMES or strength training. Intervention-related peak VE did not change over time during strength training or LF-NMES and increased slightly, but significantly over time during HF-NMES. Peak VO2 and VE were significantly higher during strength training compared to HF-NMES or LF-NMES. Oxygen saturation significantly decreased after the first measurements during HF-NMES and strength training group to baseline, while no significant changes in oxygen saturation were observed during the other measurements. Heart rate significantly increased compared to baseline in all groups at all moments and was significantly higher after strength training compared to HF-NMES or LF-NMES. Median end scores (points) for dyspnea, fatigue and muscle pain ranged from 1 to 3, from 0.5 to 2 and from 0 to 6 after HF-NMES, from 2 to 3, from 2 to 5 and from 0 to 9 after LF-NMES and from 2 to 5, from 1.5 to 4 and from 0 to 28 after strength training respectively.ConclusionsTo conclude, the metabolic load and symptom scores remain acceptable low over time with increasing training loads during HF-NMES, LF-NMES or strength training.Trial registrationTrial registration:NTR2322

ABSTRACT 392

Background and aims: A lung recruitment maneuver (RM) is an applied transient increase in transpulmonary pressure intended to increase end-expiratory lung volume and re-expand collapsed lung units. Due to the potential detrimental effects on hemodynamics by the maneuvers, there is very limited data in its use in the pediatric cardiac patient population. Aims: To demonstrate safety of lung RM in post-operative pediatric cardiac patients and evaluate the ability of lung RM to improve pulmonary compliance. Methods: A retrospective chart review was performed on a convenience sample of 62 post-operative cardiac surgical patients. IRB approval was obtained. Study patients were selected from patients who met criteria between June 2011 to May 2012 during which time a RM protocol was implemented at a free standing children’s hospital. Due to RMs generating a temporary increase in intrathoracic pressure, physiologic variables were monitored before, during, and after the RM. Results: RMs were safe and well-tolerated hemodynamically, and there was no significant change in oxygen saturation, blood pressure or heart rate during the maneuvers. RMs resulted in a post-maneuver increase in dynamic pulmonary compliance from 0.48 to 0.63 mL / cmH2O / kg (P< .001; 95% CI). An increase in dynamic compliance following completion of the RM was seen in all 62 patients. Conclusions: In this retrospective study, RMs were well tolerated by post-operative cardiac surgical patients. RMs also increased pulmonary compliance, and had no noticeable detrimental hemodynamic effects. These findings suggest RM protocols in post-operative pediatric cardiac surgical patients could be investigated in a prospective study.

Study of blood oxygen saturation, heart rate changes and plateau reaction of the Antarctic Kunlun station investigation team in different plateau environments

To explore the blood oxygen saturation and heart rate changes of the Antarctic explorers. During August 2010 to April 2011, the changes in blood oxygen saturation, heart rate and plateau reaction of 16 Antarctic expedition team in different plateau environments (Tibetan plateau versus Antarctic plateau) were monitored with the noninvasive pulse oximeter MD300-C. The extent of acute mountain sickness was determined according to the Lake Louise Consensus acute mountain reaction symptom scores and judgment method. The changes of blood oxygen saturation, heart rate at different altitudes of 110, 3650, 4300 m (96.8% ± 1.2%,89.1% ± 1.2%, 86.1% ± 2.0%, (75.0 ± 5.4) times/min, (104.0 ± 4.3) times/min, (113.0 ± 5.2) times/min,F = 214.155, 240.088,both P < 0.05). With rising latitude and elevation gradient in Antarctic plateau, the changes of blood oxygen saturation, heart rate at different altitudes of 2000, 2500, 3000, 3500 and 4087 m(91.9% ± 1.3%,90.5% ± 1.3%,87.6% ± 1.4%,85.0% ± 1.8%,81.5% ± 2.2%, (85.9 ± 3.2) times/min, (90.6 ± 2.8) times/min, (97.8 ± 4.1) times/min, (102.0 ± 3.4) times/min, (106.3 ± 3.9) times/min, F = 105.418, 90.174, both P < 0.05). Levels of blood oxygen saturation and heart rate were both correlated with the risk of altitude sickness (r = -0.446 and 0.565, both P < 0.05). As the increases of altitude, there are significant changes in oxygen saturation, heart rate of the Antarctic explorers. And with the increases of altitude, the risk of altitude sickness gradually increases.

Effect of an oxygen pressure injection (OPI) device on the oxygen saturation of patients during dermatological methyl aminolevulinate photodynamic therapy

Methyl aminolevulinate photodynamic therapy (MAL-PDT) (a topical treatment used for a number of precancerous skin conditions) utilizes the combined interaction of a photosensitizer (protoporphyrin IX (PpIX)), light of the appropriate wavelength, and molecular oxygen to produce singlet oxygen and other reactive oxygen species which induce cell death. During treatment, localized oxygen depletion occurs and is thought to contribute to decreased efficacy. The aim of this study was to investigate whether an oxygen pressure injection (OPI) device had an effect on localized oxygen saturation levels and/or PpIX fluorescence of skin lesions during MAL-PDT. This study employed an OPI device to apply oxygen under pressure to the skin lesions of patients undergoing standard MAL-PDT. Optical reflectance spectrometry and fluorescence imaging were used to noninvasively monitor the localized oxygen saturation and PpIX fluorescence of the treatment area, respectively. No significant changes in oxygen saturation were observed when these data were combined for the group with OPI and compared to the group that received standard MAL-PDT without OPI. Additionally, no significant difference in PpIX photobleaching or clinical outcome at 3 months between the groups of patients was observed, although the group that received standard MAL-PDT demonstrated a significant increase (p<0.05) in PpIX fluorescence initially and both groups produced a significant decrease (p<0.05) after light irradiation. In conclusion, with this sample size, this OPI device was not found to be an effective method with which to improve tissue oxygenation during MAL-PDT. Further investigation is therefore required to find a more effective method of MAL-PDT enhancement.

The influence of retinal oxygenation on the clinical outcomes in eyes with epiretinal membrane after successful vitrectomy

AbstractPurpose In the present study patients with epiretinal membrane underwent 23G vitrectomy and ICG membrane peeling. Little information is available about the effects of this treatment on retinal oxygenation. Hence, we set out to investigate the effects of vitrectomy on retinal oxygenation in patients with epiretinal membrane.Methods In this unmasked, prospective study, patients with macular edema as a result of epiretinal membrane scheduled to undergo vitrectomy without endotamponade, were included. The main outcome measure was oxygenation of the retinal vessels. The measurement of oxygenation in retinal vessels and retinal vessel diameters was performed with the Retinal Vessel Analyzer at baseline, at day 1, day 7, week 4, and week 12 after surgery. At each follow‐up visit, a high‐definition OCT examination and ETDRS visual acuity were also performed.Results Retinal venous diameter increased significantly at the first follow‐up examination. There was no significant change in oxygen saturation in retinal arteries. Retinal oxygen saturation in retinal veins showed a tendency to decrease at the 3 months follow‐up visit. Visual acuity did not change significantly after 3 months. Central retinal thickness was decreased after 3 months as expected but not to a significant level.Conclusion Vitrectomy for epiretinal membrane may show beneficial short‐term effects on retinal oxygenation. In eyes with macular edema due to other pathologies with retinal ischemia, vitrectomy may be performed as an additional treatment modality. Further studies evaluating whether these effects are associated with changes in long‐term visual acuity are warranted.

Exhaled breath condensate purines correlate with lung function in infants and preschoolers

Although airway inflammation begins early in life in children with chronic respiratory diseases, current methods to assess this inflammation are invasive and entail significant risk. Measurement of exhaled breath condensate (EBC) purines and other biomarkers offers a less invasive method to assess airway inflammation; however, the feasibility and utility of EBC biomarkers in young children has not been established. EBC was collected from children <3 years old with cystic fibrosis or other lung diseases during clinically indicated infant pulmonary function tests (iPFTs). EBC concentrations of the purine biomarkers adenosine (Ado), adenosine monophosphate (AMP), and the dilution marker urea were measured using mass spectrometry. EBC was successfully collected (average volume 330 ± 170 µl) from preschool children (age 2.3 ± 0.8 years) in 15 of 17 iPFTs. No significant changes in oxygen saturation (96.9 ± 1.6 start, 96.8 ± 1.7 end, P = 0.389) or respiratory rate (35.2 ± 7.5 start, 34.6 ± 7.9 end, P = 0.443) were observed during collection. Ado and AMP were successfully measured in 13/15 samples [8 cystic fibrosis (CF)]. EBC AMP to Ado ratio (AMP/Ado) negatively correlated with forced expiratory volume at 0.5 sec (FEV(0.5) , r = -0.71, P < 0.01) and positively with the ratio of residual volume to total lung capacity (RV/TLC, r = 0.66, P = 0.015). These correlations remained statistically significant in the subset with CF. EBC can be safely collected and analyzed in preschool children using commercially available equipment. The EBC AMP/Ado ratio correlates with measures of infant lung function and may be a less invasive means of monitoring airway inflammation in this population.

Verbal communication for the ventilator‐dependent patient requiring an inflated tracheotomy tube cuff: A prospective, multicenter study on the Blom tracheotomy tube with speech inner cannula

The purpose of this study was to present our findings on the impact of the Blom tracheotomy tube with speech inner cannula on voice production abilities and speech intelligibility scores of ventilator-dependent patients requiring a fully inflated tracheotomy tube cuff. Prospective single group case-series design permitted consecutive accrual of 23 adult inpatients from acute care and rehabilitation settings. Maximum ambient room noise, voice intensity, phonation duration of vowel /a/, and speech intelligibility scores were determined over 3 sessions. All participants achieved audible voicing with the Blom tracheotomy tube. Voice intensity was significantly greater than ambient room noise by >10 dB SPL (p = .003). Speech intelligibility scores improved significantly from 80% to 85% (p = .03). Phonation duration averaged from 3.30 to 3.45 seconds. There were no significant changes in oxygen saturation (p > .05), and no significant complications occurred. The Blom tracheotomy tube with speech inner cannula permitted individuals requiring mechanical ventilation with a fully inflated tracheotomy tube cuff to produce excellent speech intelligibility for verbal communication. © 2012 Wiley Periodicals, Inc. Head Neck, 2013.

Six-Minute Walk Test-Normal Values of School Children Aged 7–12 Y in India: A Cross-Sectional Study

To establish normal reference standards for six minute walk test of children aged between 7-12 y in India. Healthy children aged between 7 to 12 y were recruited randomly from the selected schools in India. 400 children were included .Six minute walk test (MWT) was performed according to standardized ATS guidelines. Distance walked in 6 min, Heart rate (HR), Blood pressure (BP), Oxygen saturation, anthropometric measurements and level of dyspnea were taken as outcome measures. Mean distance walked in 6 min was 609 ± 166 m, with significant difference between boys and girls( p < 0.001). Boys covered more distance than girls. Heart rate increased from a baseline of 82.73 ± 1.63 to a maximum of 104.32 ± 3.11; heart rate recovery occurred at 5 min in both the genders. SBP increased from baseline 109 ± 2.38 to maximum of 121.86 ± 1.75 at the end of the test, with no significant increase in DBP which was 68.51 ± 2.21 and 69 ± 2.78 at the end of the test. No significant change in oxygen saturation and dyspnea was observed during the test. Mean oxygen saturation was 97% at baseline, with an immediate drop of 96%. In this study, the mean distance covered in 6 min by boys was 670.74 ± 86.21 m and girls were 548.93 ± 44.78 m.

Imaging of CTLA4 Blockade–Induced Cell Replication with 18F-FLT PET in Patients with Advanced Melanoma Treated with Tremelimumab

Preclinical models predict that blockade of the coinhibitory molecule cytotoxic T lymphocyte-associated antigen 4 (CTLA4) on lymphocytes results in the release of a cell cycle inhibitory checkpoint, allowing lymphocyte proliferation, tumor targeting, and regression. However, there is a paucity of data demonstrating that lymphocyte proliferation does occur in humans treated with CTLA4-blocking antibodies. We tested the role of whole-body molecular imaging in patients with advanced melanoma receiving the CTLA4-blocking antibody tremelimumab, allowing the analysis of changes in glucose metabolism using the PET probe (18)F-FDG and cell replication with the PET probe 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT). PET/CT scans obtained at a median of 2 mo after initial dosing did not demonstrate significant changes in lesion size or (18)F-FDG or (18)F-FLT uptake when focusing on metastatic lesions. Similarly, there was no difference in (18)F-FDG uptake in the non-melanoma-involved spleen. However, there were significant increases in standardized uptake values for (18)F-FLT in the spleen using post- and pretremelimumab treatment scans. Molecular imaging with the PET probe (18)F-FLT allows mapping and noninvasive imaging of cell proliferation in secondary lymphoid organs after CTLA4 blockade in patients with metastatic melanoma.

Comparative Study of Three Sedative Techniques During Shock Wave Lithotripsy.

Background: Many authors found that dexmedetomidine is an effective, safe drug for sedation during extracorporeal shock wave lithotripsy (ESWL). Dexmedetomidine is a lipophilic α2- agonist ,which sedates patients by reducing sympathetic activity and the level of arousal ,thus patients lie calmly in beds but are easily roused to full consciousness. In the present study, the sedative, haemodynamics, and respiratory effects, and recovery time of dexmedetomidine and dexmedetomidine/fentanyl combination were compared to one of the commonly used sedative analgesic regimen (midazolam/fentanyl) in patients undergoing lithotripsy. Methods: Sixty ASA I - II patients undergoing (ESWL) were divided into three equal groups and were randomized to receive either dexmedetomidine (dex group), dexmedetomidine fentanyl combination (dex/fentanyl group) or midazolam fentanyl (midazolam/fentanyl group) . In dex group: Initial loading dose of dex 1 μg/kg was infused for 10 min followed by continuous infusion 0.1-0.7 μg/kg/h. In dex/fentanyl group, initial dose of 1 μg/kg dex was infused over 10 min followed by continuous infusion 0.1-0.7 μg/kg/h. At the same time, fentanyl infusion started 1 μg/kg over 10 min. In midazolam/fenatnyl group, midazolam 0.05 mg/kg and fentanyl 1 μg/kg were infused over 10 min followed by continuous infusion of normal saline. Heart rate (HR), mean arterial pressure (MAP), oxygen saturation (SpO2), and respiratory rate were recorded. Pain intensity was evaluated with a visual analog scale. Depth of sedation was monitored using Ramsay sedation score (RSS). Recovery time, rescue analgesic and sedative were recorded. Results: In all groups, no significant changes in oxygen saturation and respiratory rate were observed. In dex and dex/fentanyl groups there was a significant decrease in heart rate and mean arterial pressure during and post procedure. Supplemental fentanyl was required in 80% of patients in dex group to achieve a satisfactory level of analgesia (vs. 25% of patients in dex/fentanyl group and 40% of patients in midazolam/fentanyl group). Also 70% of patients in dex group received rescue midazolam vs. 15% in dex/fentanyl group and 20% in midazolam/fentanyl group. Time to home readiness was longer in dex,and dex/fentanyl groups than in midazolam/fentanyl group(80, 75, and 44 min), respectively. Conclusion: Dexmedetomidine alone does not appear to be suitable for sedation in patients undergoing ESWL. Combination of dexmedetomidine with fentanyl can be used safely and effectively for sedation and analgesia during ESWL, so it could be an alternative to conventional midazolam/fentanyl regimen but it is associated with longer recovery time.

Comparative Study of Three Sedative Techniques During Shock Wave Lithotripsy.

Background: Many authors found that dexmedetomidine is an effective, safe drug for sedation during extracorporeal shock wave lithotripsy (ESWL). Dexmedetomidine is a lipophilic α2- agonist ,which sedates patients by reducing sympathetic activity and the level of arousal ,thus patients lie calmly in beds but are easily roused to full consciousness. In the present study, the sedative, haemodynamics, and respiratory effects, and recovery time of dexmedetomidine and dexmedetomidine/fentanyl combination were compared to one of the commonly used sedative analgesic regimen (midazolam/fentanyl) in patients undergoing lithotripsy. Methods: Sixty ASA I - II patients undergoing (ESWL) were divided into three equal groups and were randomized to receive either dexmedetomidine (dex group), dexmedetomidine fentanyl combination (dex/fentanyl group) or midazolam fentanyl (midazolam/fentanyl group) . In dex group: Initial loading dose of dex 1 μg/kg was infused for 10 min followed by continuous infusion 0.1-0.7 μg/kg/h. In dex/fentanyl group, initial dose of 1 μg/kg dex was infused over 10 min followed by continuous infusion 0.1-0.7 μg/kg/h. At the same time, fentanyl infusion started 1 μg/kg over 10 min. In midazolam/fenatnyl group, midazolam 0.05 mg/kg and fentanyl 1 μg/kg were infused over 10 min followed by continuous infusion of normal saline. Heart rate (HR), mean arterial pressure (MAP), oxygen saturation (SpO2), and respiratory rate were recorded. Pain intensity was evaluated with a visual analog scale. Depth of sedation was monitored using Ramsay sedation score (RSS). Recovery time, rescue analgesic and sedative were recorded. Results: In all groups, no significant changes in oxygen saturation and respiratory rate were observed. In dex and dex/fentanyl groups there was a significant decrease in heart rate and mean arterial pressure during and post procedure. Supplemental fentanyl was required in 80% of patients in dex group to achieve a satisfactory level of analgesia (vs. 25% of patients in dex/fentanyl group and 40% of patients in midazolam/fentanyl group). Also 70% of patients in dex group received rescue midazolam vs. 15% in dex/fentanyl group and 20% in midazolam/fentanyl group. Time to home readiness was longer in dex,and dex/fentanyl groups than in midazolam/fentanyl group(80, 75, and 44 min), respectively. Conclusion: Dexmedetomidine alone does not appear to be suitable for sedation in patients undergoing ESWL. Combination of dexmedetomidine with fentanyl can be used safely and effectively for sedation and analgesia during ESWL, so it could be an alternative to conventional midazolam/fentanyl regimen but it is associated with longer recovery time.

Pharmacological stress myocardial perfusion scintigraphy: use of a modified adenosine protocol in patients with asthma

Stress radionuclide myocardial perfusion scintigraphy (MPS) using adenosine pharmacological vasodilatation is the preferred method in many centres because of its convenience, safety and speed. It can, however, cause bronchospasm and hence its use is avoided in patients with known or suspected bronchospasm. Owing to service pressures, we use technologist-led adenosine stressing for patients referred for MPS studies. We use a modified adenosine infusion protocol under medical supervision for patients with asthma to prevent and minimize adenosine-induced bronchospasm. In this study, we audited our use of this modified protocol in asthmatic patients and compared the side-effect profile with the standard adenosine protocol used in nonasthmatic patients. We audited 50 consecutive patients with asthma attending our department for stress MPS. All patients were taking regular inhalers+/-oral steroids. Patients who had exacerbation of asthma requiring hospital admission during the preceding 6 months were excluded. Before commencing the infusion, two inhaled puffs of salbutamol were administered. A modified adenosine infusion protocol was used, starting initially at a rate of 70 microg/kg/min and increasing to the standard 140 microg/kg/min within 1 min and then maintained for a further 5 min. Technetium-99m tetrofosmin was injected at 3 min. Blood pressure (BP), pulse rate (PR), oxygen saturation and ECG were monitored before, during and at the end of the infusion. All side effects were recorded. Fifty-eight consecutive patients without asthma were included as controls and received the standard 140 microg/kg/min infusion over 6 min. One hundred and eight patients, 50 with asthma and 58 without asthma, were entered into the study. The test was stopped early in two patients (4%) with asthma and 11 patients (19%) without asthma (chi=5.679; P=0.017). Proportionally, more nonasthmatics developed shortness of breath (SOB) (47 of 58, 81% without asthma vs. 35 of 50, 70% with asthma); however, this did not reach statistical significance (chi=1.788, P=NS). Three out of 50 (6%) patients in the asthma group experienced severe SOB but only one of those 50 patients (2%) developed bronchospasm, manifesting as wheeze. In the nonasthma group, five of 58 patients (8.6%) experienced severe SOB but none developed a wheeze. Less flushing (16 of 50, 32% vs. 36 of 58, 62%; P=0.002), dizziness (12 of 50, 24% vs. 26 of 58, 45%; P=0.023) and neck/throat pain (5 of 50, 10% vs. 16 of 58, 28%; P=0.021) was observed in the modified infusion group with asthma compared with the standard infusion group without asthma. Statistical significance was observed in these three side effects. No significant difference in other side effects was noted. A similar decrease in mean diastolic BP, and an increase in mean PR were observed during the infusion in both asthmatic and nonasthmatic groups. The mean systolic BP decreased significantly in nonasthmatic patients (P<0.001) but not in the asthmatic group. No significant change in oxygen saturation was seen during infusion in the asthmatic group. The modified adenosine infusion protocol with salbutamol premedication can be used in patients with asthma. This protocol resulted in fewer side effects and changes in BP and PR in asthmatic patients compared with nonasthmatic patients who received the standard adenosine infusion.

Analysis of masseter muscle oxygenation and mandibular movement during experimental gum chewing with different hardness

Objective. The purpose of this study was to analyze masseter muscle oxygenation changes and mandibular movements in the experimental chewing of gums with different hardness. Material and Methods. Subjects for this experiment comprised 23 male volunteers with normal occlusion. Mean age (SD) was 28.3 (2.2) years. Three kinds of gum with mean fracture stresses of 3.52×104 N/m2 (Gum 1), 5.35×104 N/m2 (Gum 2), and 14.0×104 N/m2 (Gum 3) were used. The subjects were instructed to chew gum for 80 s (100 strokes) on the voluntary chewing side at a pace of 1.25 strokes/s. Oxygen saturation in the masseter muscle and mandibular movement during gum chewing were recorded simultaneously using near-infrared spectroscopy tissue oximetry and mandibular kinesiography. Results. For Gum 1, no subjects showed any significant changes in oxygen saturation during gum chewing. For Gum 2, 10 subjects showed no significant changes, whereas the other 13 showed significant decreases in oxygen saturation. For Gum 3, significant decreases were seen in all subjects. Chewing motions were larger and velocity was higher in gum chewing with decreases in masseter muscle oxygen saturation compared to chewing showing no significant changes. Conclusions. The results suggest that the harder texture of gum enlarges chewing motion and increases chewing velocity, with an increase in the contribution of anaerobic metabolism to energy yield in masseter muscle. Differences in the responses to gum hardness may indicate individual differences in muscle fatigue tendencies when chewing harder foods.