Cuff Pressure Research Articles

Influence of cuff stiffness on hemodynamics and perceived cuff pressure in the upper extremities in males and females: implications for practical blood flow restriction training

BackgroundPractical blood flow restriction (pBFR) during exercise is a cost-saving alternative to traditional blood flow restriction using pneumatic cuffs, particularly when exercising in a group setting. Depending on the pBFR technique, several factors (e.g., cuff width, limb circumference) have already been shown to be of importance when applying the pBFR pressure. Given that elastic cuffs are often used for pBFR, the cuff stiffness might be an additional influencing factor. Therefore, the present study compared the acute effects of three elastic cuffs with identical width but different stiffness (high stiffness (HS), medium stiffness (MS), and low stiffness (LS)) on hemodynamic measures and perceived cuff pressure at rest.MethodsIn a randomized, counter-balanced cross-over study, 36 young and normotensive participants completed three experimental trials. After a 10-min rest period in supine position, the cuff was loosely and proximally applied to the right upper arm. Following baseline data recording, the cuff was successively tightened in 10%-increments with respect to the limb circumference (%overlap) until arterial blood flow was occluded. At baseline and during each %overlap, systolic peak blood flow velocity of the brachial artery, rating of perceived cuff pressure, as well as muscle oxygen saturation and total hemoglobin concentration of the biceps brachii muscle were recorded.ResultsThe %overlap required to occlude arterial blood flow was different between the three cuffs (HS: 30.9 ± 3.8%, MS: 43.9 ± 6.1%, LS: 54.5 ± 8.3%). Furthermore, at 30% overlap, systolic peak blood flow velocity was lower when applying the HS (9.0 ± 10.9 cm∙s− 1) compared to MS (48.9 ± 21.9 cm∙s− 1) and LS cuff (62.9 ± 19.1 cm∙s− 1). Rating of perceived cuff pressure at 30% overlap was higher when using the HS (6.5 ± 1.5 arbitrary unit (a.u.)) compared to MS (5.1 ± 1.4 a.u.) and LS cuff (4.9 ± 1.5 a.u.) with no difference between the MS and LS cuff. However, muscle oxygen saturation and total hemoglobin concentration were not different between the three cuffs.ConclusionsThe present study revealed that the cuff stiffness influenced blood flow velocity and arterial occlusion pressure. Therefore, cuff stiffness seems an important factor for the application of pBFR.

Remote Ischemic Conditioning for Acute Stroke

Despite some promising preclinical and clinical data, it remains uncertain whether remote ischemic conditioning (RIC) with transient cycles of limb ischemia and reperfusion is an effective treatment for acute stroke. To evaluate the effect of RIC when initiated in the prehospital setting and continued in the hospital on functional outcome in patients with acute stroke. This was a randomized clinical trial conducted at 4 stroke centers in Denmark that included 1500 patients with prehospital stroke symptoms for less than 4 hours (enrolled March 16, 2018, to November 11, 2022; final follow-up, February 3, 2023). The intervention was delivered using an inflatable cuff on 1 upper extremity (RIC cuff pressure, ≤200 mm Hg [n = 749] and sham cuff pressure, 20 mm Hg [n = 751]). Each treatment application consisted of 5 cycles of 5 minutes of cuff inflation followed by 5 minutes of cuff deflation. Treatment was started in the ambulance and repeated at least once in the hospital and then twice daily for 7 days among a subset of participants. The primary end point was improvement in functional outcome measured as a shift across the modified Rankin Scale (mRS) score (range, 0 [no symptoms] to 6 [death]) at 90 days in the target population with a final diagnosis of ischemic or hemorrhagic stroke. Among 1500 patients who were randomized (median age, 71 years; 591 women [41%]), 1433 (96%) completed the trial. Of these, 149 patients (10%) were diagnosed with transient ischemic attack and 382 (27%) with a stroke mimic. In the remaining 902 patients with a target diagnosis of stroke (737 [82%] with ischemic stroke and 165 [18%] with intracerebral hemorrhage), 436 underwent RIC and 466 sham treatment. The median mRS score at 90 days was 2 (IQR, 1-3) in the RIC group and 1 (IQR, 1-3) in the sham group. RIC treatment was not significantly associated with improved functional outcome at 90 days (odds ratio [OR], 0.95; 95% CI, 0.75 to 1.20, P = .67; absolute difference in median mRS score, -1; -1.7 to -0.25). In all randomized patients, there were no significant differences in the number of serious adverse events: 169 patients (23.7%) in the RIC group with 1 or more serious adverse events vs 175 patients (24.3%) in the sham group (OR, 0.97; 95% CI, 0.85 to 1.11; P = .68). Upper extremity pain during treatment and/or skin petechia occurred in 54 (7.2%) in the RIC group and 11 (1.5%) in the sham group. RIC initiated in the prehospital setting and continued in the hospital did not significantly improve functional outcome at 90 days in patients with acute stroke. ClinicalTrials.gov Identifier: NCT03481777.

Inhalation anesthesia in the cat: Development of cuff pressure when using nitrous oxide

During inhalation anesthesia with nitrous oxide in oxygen the pressure in the cuff of the endotracheal tube may increase due to diffusion of nitrous oxide into the cuff. The aim of the study was to investigate the development of cuff pressure during nitrous oxide anesthesia under clinical conditions in feline patients and to identify possible influencing factors such as tube size and gas flow rate. The prospective study included cats scheduled for inhalation anesthesia with nitrous oxide for a minimum duration of 60 minutes at the Department for Small Animals of the University of Leipzig. Cuff pressure was adjusted with a cuff manometer and its development was recorded. In total, the cuff pressure values of 24 cats were recorded. Animals were allocated into groups by tube size (ID 4.0 mm and ID 4.5 mm) and by fresh gas flow rate: low flow rate (0.6 l/min) and high flow rate (3 l/min). During anesthesia, cuff pressure increased over time, with statistical significance occurring from 45 minutes onwards in comparison to the initial cuff pressure (p=0.005). After 60 minutes, there was a mean cuff pressure increase of 3 cmH2O. Despite this moderate mean increase, highly variable pressure values up to 48 cmH2O in individual animals were recorded. No cat reached the termination criterion of 60 cmH2O cuff pressure. Effects of tube size (p=0.63) and flow rate (p=0.334) on the cuff pressure were not evident. After a period of 45 minutes of nitrous oxide administration, a significant increase in cuff pressure occurs in the cat. However, tube size and total gas flow rate do not seem to influence the cuff pressure development. When using nitrous oxide during inhalation anesthesia, regular cuff pressure evaluation and correction are necessary and hence recommended in feline patients. As individual pressure changes may be highly variable, no fixed recommendations for optimal management are possible.

Personalized intermittent pneumatic calf compression frequency for augmenting foot blood perfusion: The optimized effect and a personalized mode predicting method

Intermittent pneumatic compression (IPC) therapy has been adopted in prevention and treatment of ischemic-related peripheral vascular diseases. The aim of this study is to provide an approach to personalize the compression strategy of IPC therapy for maximizing foot skin blood flow. In this study, we presented a method to predict the optimized compression mode (OCM) for each subject based on biomechanical features extracted from experimental data tested with multiple IPC modes. First, to demonstrate the blood flow enhancing effect by applying the personalized OCM, four IPC modes of different frequency settings were tested on a total of 24 subjects. The frequency settings were adjusted by deflating-waiting time, which was defined as the total time length from the start of cuff deflation to the start of next compression. The foot skin blood perfusion and IPC air cuff pressure were monitored during the experiments. The personalized OCM was defined as the certain IPC mode that has the highest blood perfusion augmentation (BPA). Compared with the rest stage blood perfusion, the personalized OCM settings resulted in >50% of augmentation for 75% of healthy subjects (maximum augmentation at 244%) and >20% augmentation for 75% of patients with diabetes (maximum augmentation at 180%). Second, for predicting the OCM, we establish a random forest model based on the features extracted from the experimental data. The binary classification resulted in acceptable prediction performance (AUC > 0.7). This study might inspire new IPC strategies for improving foot microcirculation.

Tourniquet Practice Among Orthopaedic Surgeons in Saudi Arabia.

Introduction This study aimed to evaluate the knowledge of tourniquet use among orthopedic surgeons in Saudi Arabia and assess the practical aspects of their use of tourniquets and the complications they have experienced in their practices. Materials and methods This cross-sectional study was conducted from December 2022 to February 2023. An online questionnaire was distributed among orthopedic surgeons and trainees in Saudi Arabia, and the surgeons' knowledge of tourniquet use was assessed using 17 questions. To investigate tourniquet usage, the participants were divided into three groups: orthopedic residents, specialists, and consultants. An upper limb cuff pressure (CP) of 200 mmHg and a lower limb CP of 250 mmHg were chosen as the cut-off values, and the doctors' choices were compared against literature recommendations using these measures. Result A total of 205 participants filled out the questionnaires; 130 residents, 15 consultants, and 60 specialists, with more males (175/205) than females responding. One hundred and twenty-one surgeons placed the cuff on patients by themselves, while 50 (24.3%) surgeons asked nurses for aid; 135 (65.6%) of them work in teaching hospitals, while 50 (24.3%) work in community hospitals. The incidence of post-tourniquet syndrome was unrelated to expertise (p=0.12). Conclusion When applied properly, tourniquets prevent excessive bleeding and keep the operative field clean during limb surgeries. This study aims to inspire the orthopedic community to reconsider long-held practices, especially regarding tourniquet pressure. The addition of ligature safety education to orthopedics training and outlining the settings and procedures for applying pressure should also be considered. The orthopedic community should set CP and process criteria to avoid complications. This study showed the importance of modifying the training of orthopedic residents to raise awareness and prevent unpleasant events from occurring.

The Role of Artificial Urinary Sphincter in Female Incontinence in 2023: A Literature Update

This in-depth analysis of the literature provides a 2023update on the crucial function of artificial urinarysphincters (AUS) in the treatment of femaleincontinence. This review illustrates the tremendousadvancements in AUS technology, particularly theintroduction of flexible cuff pressure and occlusive cufftechniques, which have considerably improvedtreatment outcomes and patient satisfaction. It drawson the most recent research from the last ten years.

Impact of Blood Flow Restriction Exercise on Central Hemodynamics and Fluid Regulating Hormones.

The purpose of this study is to characterize both the efficacy of altered restriction pressures and consequences of optimized blood flow restriction (BFR) for altering the cardiovascular and fluid regulating response in humans. This work comprised a series of related trials. Phase 1: during semi-recumbent cycling (5 min, 60 W) with BFR at 0%, 50%, 75%, 100%, and 125% of participants' lowest arterial occlusion pressure (LOP) echocardiographic images were collected alongside continuous heart rate (HR) and blood pressure (BP). In phase 2, 24 h fluid balance (intake-output) and fluid-regulating hormone responses were measured after a practical BFR exercise session (treadmill walking: 5·3 min, 1 min rest, 5 km·h -1 , 5% incline, 100% LOP). Phase 3 examined the magnitude and effect of blood volume distribution following BFR treadmill walking using a modified CO-rebreathe technique. Cardiac ejection fraction remained stable irrespective of cuff pressure and despite a reduction in end-diastolic volume (Δ of 11 ± 9 mL, P = 0.02). HR and BP were highest at 100% LOP (ΔHR = 18 ± 19 bpm, ΔSBP = 51 ± 30 mm Hg, ΔDBP = 33 ± 15 mm Hg, ΔRate Pressure Product = 76 ± 32 bpm·mm Hg·100 -1 ). BFR treadmill walking stimulated a greater release of fluid-regulating hormones than normal walking (Δrenin = BFR: 25.3 ± 24.2 vs CON: 9.1 ± 11.8 ng·L -1 ; Δcopeptin = BFR: 50.1 ± 97.9 vs. CON: 0.43 ± 0.8 pmol·L -1 ), but no difference in fluid retention was observed ( P = 0.2). Approximately 27% of total blood volume was confined to the legs during BFR, but the relative volume trapped in the legs was not related to fluid-regulating hormone release (renin r = -0.04, P = 0.9; copeptin r = 0.27, P = 0.3). BFR exercise elicits the largest cardiovascular effect using 100% LOP, with evidence of appreciable fluid regulating hormonal response during a typical BFR exercise session. The relative volume of blood sequestered in the limb does not appear to drive this response.

Technical evaluation of a simulator for accurate reproduction of oscillometric blood pressure pulses, providing traceability for automated oscillometric sphygmomanometers

Oscillometric blood pressure measurement devices are not directly traceable to primary standards. Currently, device accuracy is measured by comparison between a sample device and reference measurements in a clinical trial. We researched in this study the potential for an alternative evaluation with a simulator. Our research simulator was studied for repeatability and accuracy in delivering simulated blood pressure pulses. Clinical cuff pressure measurements were obtained, along with simultaneous recordings of oscillometric pulse waveforms, spanning the clinical range of cuff pressures, pulse intervals and pulse shapes. Oscillometric pulse peak amplitudes ranged from 1.1 to 3.6 mmHg. Simulated repeatability results showed an average Standard Deviation (SD) for pulse peaks of 0.018 mmHg; 1.0% of peak amplitudes. Comparing simulated pulse shapes, the average repeat SD was 0.015 mmHg; 0.8% of the normalised pulse shapes. The simulated accuracy results had a mean error of − 0.014 ± 0.042 mmHg with a mean accuracy of 97.8%. For pulse shape the corresponding values were − 0.104 ± 0.071 mmHg with a mean accuracy of 95.4%. The correlation between the reference and simulated pulse shapes ranged from 0.991 to 0.996 (all p < 0.00003), with a mean 0.994. We conclude that oscillometric pulses can be reproduced with high repeatability and high accuracy with our research simulator. The extended uncertainty U(p sim ) = 0.3 mmHg for the simulated pulses is dominated by the uncertainty (64%) of the clinical reference data. These results underpin the potential of the simulator to become a secondary standard for millions of oscillometric sphygmomanometers.

Non-invasive myocardial work in aortic stenosis: validation and improvement in left ventricular pressure estimation.

The non-invasive myocardial work index (MWI) has been validated in patients without aortic stenosis (AS). A thorough assessment of methodological limitations is warranted before this index can be applied to patients with AS. We simultaneously measured left ventricular pressure (LVP) by using a micromanometer-tipped catheter and obtained echocardiograms in 20 patients with severe AS. We estimated LVP curves and calculated pressure-strain loops using three different models: (i) the model validated in patients without AS; (ii) the same model, but with pressure at the aortic valve opening (AVO) adjusted to diastolic cuff pressure; and (iii) a new model based on the invasive measurements from patients with AS. Valvular events were determined by echocardiography. Peak LVP was estimated as the sum of the mean aortic transvalvular gradient and systolic cuff pressure. In same-beat comparisons between invasive and estimated LVP curves, Model 1 significantly overestimated early systolic pressure by 61 ± 5 mmHg at AVO compared with Models 2 and 3. However, the average correlation coefficients between estimated and invasive LVP traces were excellent for all models, and the overestimation had limited influence on MWI, with excellent correlation (r = 0.98, P < 0.001) and good agreement between the MWI calculated with estimated (all models) and invasive LVP. This study confirms the validity of the non-invasive MWI in patients with AS. The accuracy of estimated LVP curves improved when matching AVO to the diastolic pressure in the original model, mirroring that of the AS-specific model. This may sequentially enhance the accuracy of regional MWI assessment.

Comparison of the effect of pressure control and volume control ventilation on endotracheal tube cuff pressure in patients undergoing general anesthesia and mechanical ventilation: a parallel randomized clinical trial

BackgroundEndotracheal intubation and mechanical ventilation are prevalent interventions in the operating room and intensive care unit. Recently, the complications of endotracheal tube cuff pressure have been a topic of interest. Therefore, this study compared the effect of pressure control and volume control ventilation modes on the endotracheal cuff pressure rate in patients undergoing general anesthesia and mechanical ventilation.MethodsIn this triple-blinded randomized clinical trial, 50 patients undergoing open limb surgery and inguinal hernia were allocated to two groups of 25 based on inclusion criteria. After intubation, one group underwent ventilation on the pressure control ventilation mode, and the other underwent ventilation on the volume control ventilation mode. In both groups, using a manometer, the cuff’s pressure was first adjusted in the range of 25–30 cm of water. Then, the cuff pressure was measured at 10, 20, and 30 min intervals. The data were statistically analyzed using independent t-test, and two-way repeated measures ANOVA.ResultsThe present study’s findings showed that cuff pressure has significantly decreased over time in both study groups (F = 117.7, P < 0.001). However, a repeated measures ANOVA with a Greenhouse-Geisser correction showed no interaction between time and groups (F = 0.019, P = 0.98). The two groups had no significant difference in cuff pressure (F = 0.56, P = 0.458).ConclusionSince the cuff pressure has been significantly reduced in both groups over time, continuous monitoring of endotracheal tube cuff pressure in patients undergoing mechanical ventilation is essential. Therefore, it is suggested to keep the cuff pressure within the recommended range to prevent complications resulting from cuff pressure reduction, such as aspiration and ventilation decrease.Trial registrationThe study was registered in the Iranian Registry of Clinical Trial on 23/02/2019 (trial registration number: IRCT20181018041376N1).

Abstract P369: The Role Of Primary Cilia In The Pathogenesis And Therapy Of Hypertension In Polycystic Kidney Disease.

Primary cilia are sensory organelles, extending from the surface of vascular endothelialcells. Primary cilia dysfunctions have been linked to numerous genetic disorders,including polycystic kidney disease (PKD). Although PKD is characterized by fluid-filledcystic kidneys, cardiovascular complications such as hypertension (HTN) are the leadingcause of death in PKD patients. We demonstrated that primary cilia sense and transmitexternal mechanical stimuli such as fluid shear stress into internal biochemical reactionssuch as the release of nitric oxide (NO). This idea has only been investigated in ECs invitro . However, the importance of the vascular primary cilia in the long-term regulationof BP has not been investigated. NO-induced vasodilation is also produced in response tostimulation of eNOS by muscarinic acetylcholine receptor 3 (AChM3R) activation byacetylcholine (ACh). Using immunofluorescence staining, we generated new andsurprising data showing that AChM3R, and its signaling components, PIP2 are localizedto primary cilia and can modulate cilia function. We hypothesize that primary ciliacontribute to BP regulation in PKD through AChM3R. We showed that both, selective(cevimeline) and non-selective (ACh, CCh) activation of AChM3R led to an increase incilia length and cilia sensory function in terms of p-eNOS expression. We also generatedendothelial-specific ( Tie2Cre and VECre ) AChM3R KO mouse lines, in which AChM3R was deleted from the vascular endothelia. These mice developed high BP, as measured bytail cuff and telemetry blood pressure monitoring devices, associated with attenuated NOproduction and impaired vascular relaxation in response to ACh stimulation. Thesestudies demonstrated the physiological significance of primary cilia-derived NO in thelong-term control of vascular hemodynamics.

Effect of blood flow restriction training on pressure pain threshold and hand function among adults with persistent neck pain: A study protocol for a randomized controlled trial

Background: Persistent neck pain is a prevalent musculoskeletal condition that affects the quality of life and functional abilities of individuals. Blood Flow Restriction Training (BFRT) is a novel therapeutic approach that involves restricting blood flow to exercising muscles to enhance strength and function. However, limited research has been conducted on the effects of BFRT on pressure pain threshold and hand function in adults with persistent neck pain. This randomized controlled trial aims to investigate the potential benefits of BFRT as a treatment intervention for this population. Methods: This study will be a prospective parallel group active controlled trail done at Physiotherapy Department, Galgotias University. Ethical clearance has been obtained from Departmental Ethics Committee on 19/05/2023 with reference number DEC/PT/GU/2023 and the Trial has been registered with Clinical Trial Registry India CTRI/2023/06/053439. Informed consent will be obtained from all the participants who are eligible to be included in the study. 110 patients with persistent neck pain will be randomly allocated into two groups. The BFRT group will receive supervised training sessions three times a week for eight weeks, performing low-load resistance exercises with blood flow restriction applied using personalized cuff pressure. The control group will receive standard care for neck pain, which may include general advice, manual therapy, and/or home exercises without BFRT. The primary outcome measures will be the pressure pain threshold, assessed using a pressure Algometer, and hand function, evaluated using standardized tests such as Hand Grip Strength and Purdue Peg board Test. Results: The data obtained will be analyzed using appropriate statistical methods, and the significance level will be set at p&lt;0.05. Conclusion: This trial will contribute valuable contribution highlighting the potential benefits of BFR training in improving pressure pain threshold and hand function in adults with persistent neck pain.

Exercise responses to heart rate clamped cycling with graded blood flow restriction.

To quantify the acute effects of graded blood flow restriction on the interaction between changes in mechanical output, muscle oxygenation trends and perceptual responses to heart rate clamped cycling. Repeated measures. Twenty-five adults (21 men) performed six, 6-min cycling bouts (24 min of recovery) at a clamped heart rate corresponding to their first ventilatory threshold at 0 % (unrestricted), 15 %, 30 %, 45 %, 60 % and 75 % of arterial occlusion pressure with the cuffs inflated bilaterally from the fourth to the sixth minute. Power output, arterial oxygen saturation (pulse oximetry) and vastus lateralis muscle oxygenation (near-infrared spectroscopy) were monitored during the final 3 min of pedalling, whilst perceptual responses (modified Borg CR10 scales) were obtained immediately after exercise. Compared to unrestricted cycling, average power output for minutes 4-6 decreased exponentially for cuff pressures ranging 45-75 % of arterial occlusion pressure (P < 0.001). Peripheral oxygen saturation averaged ∼96 % across all cuff pressures (P = 0.318). Deoxyhemoglobin changes were larger at 45-75 % versus 0 % of arterial occlusion pressure (P < 0.05), whereas higher total haemoglobin values occurred at 60-75 % of arterial occlusion pressure (P < 0.05). Sense of effort, ratings of perceived exertion, pain from cuff pressure, and limb discomfort were exaggerated at 60-75 % versus 0 % of arterial occlusion pressure (P < 0.001). Blood flow restriction of at least 45 % of arterial occlusion pressure is required to reduce mechanical output during heart rate clamped cycling at the first ventilatory threshold. Whilst power decreases non-linearly above this pressure threshold, higher occlusion levels ranging 60-75 % of arterial occlusion pressure also accentuate muscle deoxygenation and exercise-related sensations.

New approaches for rapid setpoint determination and uninterrupted tracking in non-invasive continuous blood pressure monitoring based on volume-clamp method

The volume-clamp method (VCM) is a widely used non-invasive continuous blood pressure (BP) monitoring technique, but determining the volume setpoint (V0) in the open-loop phase can be time-consuming and may cause finger tissue displacement. Additionally, frequent interruptions in BP measurement are required during the closed-loop phase to reset V0. We proposed two new approaches: the proportional value method (PVM) for rapid V0 determination in the open-loop phase and the uninterrupted V0 tracking method (UVTM) in the closed-loop phase. PVM adaptively searches for V0 by analyzing the shape index (Prop) of the plethysmographic (PG) signal under constant cuff pressure, while UVTM introduces a new vascular compliance calculation method in closed-loop phase to track changes in V0 without interrupting BP measurement. We describe the non-invasive continuous BP monitor (NC-BPM) based on these methods. Experimental results show that PVM can accurately determine V0, with a mean arterial pressure error of −1.72 ± 2.80 mmHg when compared to oscillometric method (OSCM). UVTM in NC-BPM produced a mean absolute error (MAE) of 2.44 ± 2.91 mmHg for mean arterial pressure (MAP) in induced BP fluctuation test compared to the Nexfin monitor. In the clinical study with invasive reference, the MAE in measuring MAP by NC-BPM was 4.69 ± 5.39 mmHg. Our results show that PVM and UVTM are highly accurate and reliable, with the potential to integrate effectively into VCM-based BP monitoring devices that could benefit patients, healthcare providers, and researchers.

Limb occlusion pressure versus standard tourniquet inflation pressure in minor hand surgery: a randomized controlled trial

BackgroundIn minor hand surgery, tourniquet is typically inflated to 250 mmHg. The pressure may be too high and cause unnecessary adverse effects. Limb occlusion pressure plus safety margin or recommended tourniquet pressure (RTP), has been reported as optimal pressure to provide bloodless field in limb surgeries. This study aimed to compare the RTP with the standard tourniquet pressure of 250 mmHg in minor hand surgery.MethodsA double-blinded randomized control trial was conducted from July to December 2019 and June 2020 to May 2021. Patients were randomly assigned into two groups: RTP and 250 mmHg with 3:1 ratio allocation. The outcomes were measurement of cuff pressure reduction, time to develop of tourniquet pain and discomfort, pain score, discomfort score, motionless and bloodless of operative field determined by the surgeon’s satisfaction.ResultsA total of 112 patients were included, 84 were in RTP and 28 were in 250 mmHg group. Mean of tourniquet pressure was significantly lower in the RTP group (228.3 ± 17.2 mmHg) (P < 0.001). Even though, time to develop pain was not significantly different, the RTP group reported significantly less pain and discomfort, according to the pain score (P = 0.02) and discomfort score (P = 0.017). The RTP group provided better motionless field, while both groups equally created a bloodless field.ConclusionThe RTP significantly reduced tourniquet related pain and discomfort during minor hand surgeries. It provided better motionless operative field and adequate bloodless field. Therefore, the RTP should be considered as optimal tourniquet pressure for minor hand surgeries.Trial registrationTCTR20210519001 (retrospectively registered).Level of evidenceI.

Pain history and experimental pressure pain responses in adolescents: Results from a population-based birth cohort.

Sensitized pain mechanisms are often reported in musculoskeletal pain conditions, but population-based paediatric studies are lacking. We assessed whether adolescents with musculoskeletal pain history had evidence of increased responsiveness to experimental pressure stimuli. Data were from 1496 adolescents of the Generation XXI birth cohort. Pain history was collected using the Luebeck Pain Questionnaire (self-reported at 13, parent-reported at 7 and 10 years). Two case definitions for musculoskeletal pain were considered: (1) cross-sectional-musculoskeletal pain lasting more than 3 months at age 13 and (2) longitudinal-musculoskeletal pain at age 13 with musculoskeletal pain reports at ages 7 and/or 10. Lower limb cuff pressure algometry was used to assess pain detection and tolerance thresholds, conditioned pain modulation effects (CPM, changes in thresholds in the presence on painful conditioning) and temporal summation of pain effects (TSP, changes in pain intensity to 10 phasic painful cuff stimulations). Adolescents with musculoskeletal pain at age 13 plus a history of pain in previous evaluations (longitudinal definition) had lower pain tolerance thresholds compared to the remaining sample (40.2 v. 49.0 kPa, p = 0.02), but showed no differences in pain detection threshold, CPM effect and TSP effect. Pain sensitivity, CPM effects and TSP effects were not significantly different when the current pain only case definition (cross-sectional) was used. Adolescents with current musculoskeletal pain who had a history of pain since childhood had lower tolerance to cuff stimulation. This may suggest long-standing musculoskeletal pain since childhood may contribute to sensitisation, rather than the presence of current pain only. Repeated musculoskeletal pain up to age 13 years may contribute to higher pain sensitivity (particularly lowered pressure pain tolerance) in the general adolescent population. This does not seem to be the case when reported pain experiences are recent or when the outcomes are temporal pain summation or CPM. In this community-based paediatric sample, the vast majority showed no sign of altered pain processing, but a small fraction may reveal some pain sensitization at 13 years of age.

Changes in endotracheal tube cuff pressure with the changes in peak airway pressures during total laparoscopic hysterectomy and pelvic surgeries. A prospective and observational study

Background: The abdominal insufflation and changes in endotracheal tube (ETT) cuff pressure due to creation of pneumoperitoneum and changes in patient positioning during laparoscopic abdominal surgeries have not been explored thoroughly. Aims and Objectives: The aim of our study was to see the changes in ETT cuff pressures during creation, maintenance, release of pneumoperitoneum, and during surgical positioning. Materials and Methods: A total of 60 patients were finally taken for study. Written informed consent was taken for participation in the study as well as consent for surgery. Inclusion criteria were patients of age above 30 years, American society of anesthesiology physical status 1 and 2, patients undergoing total laparoscopic hysterectomy requiring trendelenburg positioning. Exclusion criteria were patients with pre-existing pulmonary or cardiac disease, patients with pre-existing vocal cord palsy, goitre or any other airway or thoracic pathology, pregnant or lactating females, BMI more than 25 or &lt;18.5. Changes of cuff and airway pressures before and after abdominal insufflation in supine position and after head-down or head-up positioning were analyzed and compared. Results: Baseline cuff pressure after manual inflation was 28.85±11.4 cm H2O. Significant correlation was observed between change in cuff pressure and increase in peak airway pressure at the end of the surgery (P&lt;0.05). Serial measurements of ETT cuff pressure, peak airway pressure, and ETCO2 were significantly increased compared to baseline (P&lt;0.05). Conclusion: Pneumoperitoneum in Trendelenburg position increases ETT cuff pressure probably due to increase in airway pressure. Therefore, it seems advisable to include routine monitoring of ETT cuff pressure. Objective adjusted measurement of cuff pressure and airway pressures is recommended for such surgeries.

Avaliação da pressão dos manguitos dos tubos endotraqueais em cães e gatos

Tracheal tube cuffs facilitate pulmonary ventilation and protect the lower airways from aspiration, but several complications can occur, especially when this pressure exceeds 30 cm H2O. The occurrence of hyperinflation of cuffs in dogs and cats was evaluated when inflation was performed without pressure measurement. After orotracheal intubation, the anesthetist inflated the cuff with a 5 ml syringe to obtain a pressure that he considered sufficient for tracheal sealing. A pressure test was performed to assess airway leakage. Cuff pressure was measured using a syringe designed to measure cuff pressure (AG Cuffill®). It should be noted that only 16.66% of the cuffs were within the established standard range. While 75% were below the minimum value and 8.33% were above the standard value.

Evaluation of the Effect of the Endotracheal Tube Cuff Pressure Measurement on Postoperative Sore Throat

BACKGROUND&#x0D; Following general anaesthesia, up to 62% of patients experience postoperative sore throat. Despite the fact that it resolves on its own, efforts must be made to reduce it. We wanted to evaluate the difference between conventional method and instrumental measurement of cuff pressure in incidence and severity of postoperative sore throat in this study.&#x0D; METHODS&#x0D; A prospective observational study that included 150 adult patients aged &lt; 50 years scheduled for elective surgical operation requiring general anaesthesia and endotracheal intubation. They were divided randomly into two groups: Group A included 75 patients and the adequacy of cuff inflation was generally assessed clinically and group B included 75 patients and the adequacy of cuff inflation was generally assessed by using a cuff manometer.&#x0D; RESULTS&#x0D; Incidence of postoperative sore throat in all times was significantly lower in Group B than in Group A. Prevalence of mild postoperative sore throat after one hr. was significantly higher in group B than that in group A (94.1% versus 61.4%, P= 0.001).&#x0D; CONCLUSIONS&#x0D; Impaired tracheal mucosal blood flow was an important factor in the incidence of postoperative sore throat associated with tracheal intubation and recommended that a cuff inflation pressure of 30 cmH2O should not be exceeded.

The effect of prolonged intubation on ventilator associated pneumonia: endotracheal tube cuff is really steril or not?

Aims: Endotracheal tube (ETT) design, size, cuff material, cuff pressure, and intubation duration are critical in preventing nosocomial pneumonia. We aimed to evaluate the possible infection focus potential of ETT cuff and pilot balloon, particularly in prolonged intubated patients. Methods: A total number of 66 patients who underwent orotracheal intubation and received conventional mechanical ventilation more than 48 hours in the intensive care unit (ICU), were included in this prospective cohort study. Results:The mean duration of intubation was 10.36±4.82 days. Bacteriologically confirmed positive tracheal aspirate culture was 18.2% (n=12). The most frequent positive culture was detected inside of ETT lumen with a percentage of 83.3% (n=55) and followed by cuff (27.3%, n=18), pilot balloon (13.6%, n=9), respectively. It was documented that rates of lung infections were significantly increased after 14 days (p = 0.017) and rates of cuff positive cultures were significantly increased after 10 and 14 days of incubation (p= 0.001, p=0.004). The same type of bacteriological strains was identified from both pilot balloon (n=9) and ETT cuff (n=9), simultaneously. In the remaining 9-cuff positive patients pilot balloons were sterile and ETT lumens were positive culture with the same strains as identified from the cuff. There was a statistically significant positive correlation between the intubation duration and the number of infected ETT parts (p&lt;0.001). Conclusion: ETT cuff was demonstrated to be a potential infection focus in the present study. In addition, it was observed that ETT cuff colonization increased in proportion to the intubation duration. We suggest changing ETT at appropriate time intervals in order to reduce ventilator-associated pneumonia in intubated patients.