Trendelenburg position: "put to bed" or angled toward use in your unit?

The effect of passive leg raising on the cross-sectional area of the right internal jugular vein in obese patients undergoing surgery: a prospective observational study

OBJECTIVES

To observe the association between passive leg raising (PLR) and the cross-sectional area (CSA) of the right internal jugular vein (IJV) in obese patients undergoing elective surgery.

DESIGN

Prospective observational study with randomised position sequence.

SETTING

Single-centre, tertiary care hospital in Shanghai, China.

PARTICIPANTS

Forty obese patients (body mass index (BMI) >30 kg/m²) scheduled for elective surgery were enrolled. Inclusion criteria were American Society of Anesthesiologists Physical Status Classification (ASA) physical status II-III and age ≥18 years. Exclusion criteria included history of neck surgery, severe cardiovascular disease, end-stage renal disease, severe infection or sepsis and significant coagulopathy.

OBSERVATIONS

Patients underwent ultrasound measurements of the right IJV in two positions: supine (S0) and passive leg raise at 40° (PLR40). Each position was maintained for at least 1 min prior to measurement.

PRIMARY OUTCOME

The primary outcome was to observe whether the CSA of the right IJV differed between the S0 position and passive leg elevation. In post hoc analyses, we examined factors affecting the relative CSA change (CSAγ), including neck circumference, BMI, age, sex, ASA physical status and heart rate as predictors.

RESULTS

The CSA of the right IJV was significantly larger in the PLR40 position (2.05 cm²) compared to the S0 position (1.67 cm², p=0.003). Linear regression analysis showed a slight positive correlation between neck circumference and the percentage change in CSA (correlation coefficient: 0.066, p<0.05).

CONCLUSION

The CSA of the right IJV was significantly larger in the PLR40 position in obese patients undergoing surgery.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry ChiCTR2400080513.

Hemodynamic Impact of the Trendelenburg Position: A Systematic Review and Meta-analysis

OBJECTIVE

To systematically evaluate the impact of the Trendelenburg position on hemodynamic parameters in adult patients.

DESIGN

Systematic literature review and meta-analysis using PubMed and Medline.

SETTING

All prospective interventional studies comparing the hemodynamic characteristics of patients in the horizontal supine position and Trendelenburg position.

MEASUREMENTS AND MAIN RESULTS

A total of 16 studies including 333 patients were found. The Trendelenburg position led to a statistically significant 11% increase in stroke volume compared with the supine position (mean difference [MD] = 8.27, 95% confidence interval [CI]: 1.79; 14.76, p = 0.012). A decrease in stroke volume variation (MD = -1.36, 95% CI: 2.26; -0.46, p = 0.003) and heart rate (MD = -1.65, 95% CI: -2.86; -0.44, p = 0.008) and an increase in cardiac output (MD = 0.33, 95% CI: 0.1; 0.57, p = 0.006), mean arterial pressure (standardized MD, = 0.42, 95% CI: 0.1; 0.74, p = 0.011), central venous pressure (MD = 4.13, 95% CI: 2.42; 5.84, p < 0.001), mean pulmonary artery pressure (MD = 4.25, 95% CI: 2.69; 5.81, p < 0.001), and left ventricular end-diastolic volume (MD = 16.89, 95% CI: 3.17; 30.61, p = 0.016) were found.

CONCLUSIONS

The Trendelenburg position significantly increases stroke volume and improves multiple hemodynamic parameters in adult patients. These results confirm the position's potential clinical relevance in hemodynamic management and suggest the possibility of a tailored application in selected clinical settings. The duration of the beneficial effects of the Trendelenburg position and the possible side effects should be the focus of further investigation.

Effect of passive leg raising on the cross-sectional area of the right internal jugular vein in patients with obesity: a randomised controlled trial protocol

BACKGROUND

Venous access in patients with obesity presents significant challenges. The success of central venous catheterisation largely depends on the cross-sectional area (CSA) of the internal jugular vein (IJV). While techniques like the Trendelenburg position have been traditionally used to increase IJV CSA, recent studies suggest its ineffectiveness in patients with obesity. Conversely, the potential of the effect of passive leg raising (PLR) has not been thoroughly investigated in this group of patients.

METHODS

This protocol outlines a planned randomised controlled trial to evaluate the effect of PLR on the CSA of the IJV in patients with obesity slated for central venous catheterisation. The protocol involves dividing 40 participants into two groups: one undergoing PLR and another serving as a control group without positional change. The protocol specifies measuring the CSA of the IJV via ultrasound as the primary outcome. Secondary outcomes will include the success rates of right IJV cannulation. The proposed statistical approach includes the use of t-tests to compare the changes in CSA between the two groups, with a significance threshold set at p<0.05.

ETHICS APPROVAL

This study has been approved by the Institutional Review Board of Shanghai Tongren Hospital. All the participants will provide informed consent prior to enrolment in the study. Regarding the dissemination of research findings, we plan to share the results through academic conferences and peer-reviewed publications. Additionally, we will communicate our findings to the public and professional communities, including patient advocacy groups.

TRIAL REGISTRATION NUMBER

ChiCTR: ChiCTR2400080513.

Blood pressure response to clonidine in children with short stature is correlated with postural characteristics: a retrospective cross-sectional study

BACKGROUND

Clonidine stimulation test has been widely used in the diagnosis of growth hormone deficiency in children with short stature with a high level of reliability. However, it may cause hypotension, which usually appears as headache, dizziness, bradycardia, and even syncope. It is well known that elevating the beds to make patients' feet above their cardiac level might relieve this discomfort. However, the real efficiency of this method remains to be proved while the best angle for the elevated bed is still unclear.

METHODS

A total of 1200 children with short stature were enrolled in this retrospective cross-sectional study. Age, gender, weight, and basic systolic and diastolic blood pressure were collected. Blood pressure at 1, 2, 3, and 4 h after stimulation tests were recorded. The participants were divided into 3 groups based on the angles of the elevated foot of their beds named 0°, 20°, and 40° groups.

RESULTS

At one hour after the commencement of the tests, participants lying on the elevated beds showed a higher mean increase on the change of pulse pressure. The difference in the angles of the elevated beds did not show statistical significance compared with those who did not elevate their beds (0.13 vs. 2.83, P = 0.001; 0.13 vs. 2.18, P = 0.005; 2.83 vs. 2.18, P = 0.369). When it came to 4 h after the tests began, participants whose beds were elevated at an angle around 20° had a significantly higher mean increase in the change of pulse pressure values compared with those whose beds were elevated at an angle around 40° (1.46 vs. -0.05, P = 0.042).

CONCLUSION

Elevating the foot of the beds of the patients who are undergoing clonidine stimulation tests at an angle of 20°might be a good choice to alleviate the hypotension caused by the tests.

Optimal positive end-expiratory pressure titration of intraoperative mechanical ventilation in different operative positions of female patients under general anesthesia

Objective

This study aimed to compare the effectiveness and safety of different titrated methods used to determine individual positive end-expiratory pressure (PEEP) for intraoperative mechanical ventilation in female patients undergoing general anesthesia in different operative positions, and provide reference ranges of optimal PEEP values based on the titration.

Methods

A total of 123 female patients who underwent elective open abdominal surgery under general anesthesia were included in this study. After endotracheal intubation, patients' body position was adjusted to the supine position, Trendelenburg positions at 10° and 20° respectively. PEEP was titrated from 20 cmH2O to 4 cmH2O, decreasing by 2 cmH2O every 1 min. Electrical impedance tomography (EIT), hemodynamic and respiratory mechanics parameters were continuously monitored and recorded. Optimal PEEP values and reference ranges were respectively calculated based on optimal EIT parameters, mean arterial pressure (MAP), and lung dynamic compliance (Cdyn).

Results

EIT-guided optimal PEEP was found to have higher values than those of the MAP-guided and Cdyn-guided methods for all three body positions (P < 0.001), and it was observed to more significantly inhibit hemodynamics (P < 0.05). The variable coefficients of EIT-guided optimal PEEP values were smaller than those of the other two methods, and this technique could provide better ventilation uniformity for dorsal/ventral lung fields and better balance for pulmonary atelectasis/collapse. The 95% reference ranges of EIT-guided optimal PEEP values were 4.6-13.8 cmH2O, 7.0-15.0 cmH2O and 8.6-17.0 cmH2O for the supine position, Trendelenburg 10°, and Trendelenburg 20° positions, respectively.

Conclusion

EIT-guided optimal PEEP titration was found to be a superior method for lung protective ventilation in different operative positions under general anesthesia. The calculated reference ranges of PEEP values based on the EIT-guided method can be used as a reference for intraoperative mechanical ventilation.

Monitoring, management, and outcome of hypotension in Intensive Care Unit patients, an international survey of the European Society of Intensive Care Medicine

INTRODUCTION

Hypotension in the ICU is common, yet management is challenging and variable. Insight in management by ICU physicians and nurses may improve patient care and guide future hypotension treatment trials and guidelines.

METHODS

We conducted an international survey among ICU personnel to provide insight in monitoring, management, and perceived consequences of hypotension.

RESULTS

Out of 1464 respondents, 1197 (81.7%) were included (928 physicians (77.5%) and 269 nurses (22.5%)). The majority indicated that hypotension is underdiagnosed (55.4%) and largely preventable (58.8%). Nurses are primarily in charge of monitoring changes in blood pressure, physicians are in charge of hypotension treatment. Balanced crystalloids, dobutamine, norepinephrine, and Trendelenburg position were the most frequently reported fluid, inotrope, vasopressor, and positional maneuver used to treat hypotension. Reported complications believed to be related to hypotension were AKI and myocardial injury. Most ICUs do not have a specific hypotension treatment guideline or protocol (70.6%), but the majority would like to have one in the future (58.1%).

CONCLUSIONS

Both physicians and nurses report that hypotension in ICU patients is underdiagnosed, preventable, and believe that hypotension influences morbidity. Hypotension management is generally not protocolized, but the majority of respondents would like to have a specific hypotension management protocol.

Incidence and characteristics of medical emergencies related to dental treatment: a retrospective single-center study

AIM

Although uncommon, medical emergencies arise in general dental practice. Inadequate data on their severity and frequency makes targeting medical education for general dental practitioners difficult. This also makes planning for unexpected events challenging for practitioners and makes collaborating with emergency physicians burdensome. We aimed to clarify the incidence and characteristics of a dental outpatient department's medical emergencies.

METHODS

This single-center, retrospective, observational study was undertaken with patients who visited the dental outpatient department of Okayama University Hospital during the 8-year period. The primary outcome of the study was to identify the incidence and characteristics of medical emergencies in the dental outpatient department. Then we examined the timing of medical emergencies, administered medications, and final disposition (home/admission).

RESULTS

During the period, 1,146,929 patients were enrolled. Forty-two patients (0.0037%) were consulted as medical emergencies. More than 60% of the incidents were vasovagal syncope, and dehydration and hypoglycemia were the second most prevalent at 9.5%. The most common types of dental treatments were tooth extraction (45.2%), followed by general dental treatment (28.6%), and other dental surgery such as implant placement (14.3%). Types of medical emergencies occurred equally before, during, and after dental treatment. Antihypertensive agents, sedatives, or glucose were used. For patients with emergencies, 90.5% recovered during the day and returned home, and 9.5% were hospitalized.

CONCLUSION

The incidence of medical emergencies was low in our dental outpatient department. Knowledge of basic management principles, regular education for emergency care, and practicing first aid skills are mandatory for safe patient management.

Use of a modified passive leg-raising maneuver to predict fluid responsiveness during experimental induction and correction of hypovolemia in healthy isoflurane-anesthetized pigs

OBJECTIVE To evaluate the use of a modified passive leg-raising maneuver (PLRM) to predict fluid responsiveness during experimental induction and correction of hypovolemia in isoflurane-anesthetized pigs. ANIMALS 6 healthy male Landrace pigs. PROCEDURES Pigs were anesthetized with isoflurane, positioned in dorsal recumbency, and instrumented. Following induction of a neuromuscular blockade, pigs were mechanically ventilated throughout 5 sequential experimental stages during which the blood volume was manipulated so that subjects transitioned from normovolemia (baseline) to hypovolemia (blood volume depletion, 20% and 40%), back to normovolemia, and then to hypervolemia. During each stage, hemodynamic variables were measured before and 3 minutes after a PLRM and 1 minute after the pelvic limbs were returned to their original position. The PLRM consisted of raising the pelvic limbs and caudal portion of the abdomen to a 15° angle relative to the horizontal plane. RESULTS Hemodynamic variables did not vary in response to the PLRM when pigs were normovolemic or hypervolemic. When pigs were hypovolemic, the PLRM resulted in a significant increase in cardiac output and decrease in plethysomographic variability index and pulse pressure variation. When the pelvic limbs were returned to their original position, cardiac output and pulse pressure variation rapidly returned to their pre-PLRM values, but the plethysomographic variability index did not. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested a modified PLRM might be useful for identification of hemodynamically unstable animals that are likely to respond to fluid therapy. Further research is necessary to validate the described PLRM for prediction of fluid responsiveness in clinically ill animals.

S2e guideline: positioning and early mobilisation in prophylaxis or therapy of pulmonary disorders : Revision 2015: S2e guideline of the German Society of Anaesthesiology and Intensive Care Medicine (DGAI)

The German Society of Anesthesiology and Intensive Care Medicine (DGAI) commissioneda revision of the S2 guidelines on "positioning therapy for prophylaxis or therapy of pulmonary function disorders" from 2008. Because of the increasing clinical and scientificrelevance the guidelines were extended to include the issue of "early mobilization"and the following main topics are therefore included: use of positioning therapy and earlymobilization for prophylaxis and therapy of pulmonary function disorders, undesired effects and complications of positioning therapy and early mobilization as well as practical aspects of the use of positioning therapy and early mobilization. These guidelines are the result of a systematic literature search and the subsequent critical evaluation of the evidence with scientific methods. The methodological approach for the process of development of the guidelines followed the requirements of evidence-based medicine, as defined as the standard by the Association of the Scientific Medical Societies in Germany. Recently published articles after 2005 were examined with respect to positioning therapy and the recently accepted aspect of early mobilization incorporates all literature published up to June 2014.

The effectiveness of trendelenburg positioning on the cross-sectional area of the right internal jugular vein in obese patients

Objective:

Trendelenburg positioning is a common approach used during internal jugular vein (IJV) cannulation. No evidence indicates that Trendelenburg positioning significantly increases the cross-sectional area (CSA) of the IJV in obese patients. The primary aim of this study was to determine the effectiveness of Trendelenburg positioning on the CSA of the right internal jugular vein assessed with ultrasound measurement in obese patients.

Methods:

Forty American Society of Anesthesiologists II patients with body mass index ≥30 kg/m² undergoing various elective surgeries under general endotracheal anesthesia were enrolled. Ultrasound images of the right IJV were obtained in a transverse orientation at the cricoid level. We measured the CSA of the right IJV two different conditions in a sealed envelope were applied in random order: State 0, table flat (no tilt), with the patients in the supine position, and State T, in which the operating table was tilted 20° to the Trendelenburg position.

Results:

The change in the CSA of the IJV from the supine to the Trendelenburg position (1.80 cm² vs 2.08cm²) was not significantly different. The CSA was paradoxically decreased in 10 of 36 patients when the position changed from State 0 to State T.

Conclusions:

Trendelenburg positioning does not significantly increase the mean CSA of the right IJV in obese patients. In fact, in some patients, this position decreases the CSA. The use of the Trendelenburg position for IJV cannulation in obese patients can no longer be supported.

Insights and advances in multidisciplinary critical care: a review of recent research

The intensive care unit is a work environment where superior dedication is pivotal to optimize patients' outcomes. As this demanding commitment is multidisciplinary in nature, it requires special qualities of health care workers and organizations. Thus research in the field covers a broad spectrum of activities necessary to deliver cutting-edge care. However, given the abundance of research articles and education activities available, it is difficult for modern critical care clinicians to keep up with the latest progress and innovations in the field. This article broadly summarizes new developments in multidisciplinary intensive care, providing elementary information about advanced insights in the field by briefly describing selected articles bundled in specific topics. Issues considered include cardiovascular care, monitoring, mechanical ventilation, infection and sepsis, nutrition, education, patient safety, pain assessment and control, delirium, mental health, ethics, and outcomes research.