Pleth Variability Index Values Research Articles

Suratentorial Tümör Cerrahisinde %20 Mannitol ve %3 Hipertonik Salin Kullanımlarının Beyin Relaksasyonu, Hemodinamik Parametreler, Serum Osmolaritesi ve Elektrolitleri Üzerine Etkilerinin Değerlendirilmesi

Objective: Different drugs or methods can be applied to provide brain relaxation in supratentorial tumor surgery. In our study, we aimed to evaluate effects of 20% Mannitol and 3% Hypertonic Saline (HS) used during supratentorial tumor surgery on brain relaxation, hemodynamic parameters, urine flow, fluid volume, pulse pressure variability (PPV), pleth variability index (PVI), serum osmolarity and electrolytes. Methods: The study included 60 patients aged 18-65 years, ASA I-II class, who were scheduled to undergo supratentorial tumor surgery. General anesthesia was administered with sevoflurane and remifentanil to achieve a state entropy of 40-60. Patients were allocated into two groups, with Group Mannitol receiving 20% mannitol (2.5 mL kg-1) and Group Hypertonic Saline receiving 3% HS (2.5 mL kg-1). In all patients, PPV and PVI values were planned to be ≤13%. After the dura was opened, brain relaxation scores were evaluated. Perioperative hemodynamic variables, blood gases, PVI, PPV values were recorded. Na+, K+ values, urine volume and administered fluid were recorded at 30, 45 and 60 minutes and 2-3 hours after the end of the infusion. Preoperative and postoperative BUN, creatinine and osmolarity values were recorded. Results: No statistical difference was found between demographic characteristics, brain relaxation and hemodynamic data. In HS group, PVI and PPV values were higher than Mannitol group from the beginning of infusion. In mannitol group, urine and administered fluid amounts were higher. Decrease in Na+ values was detected with Mannitol and increase with HS. It was determined that BUN and creatinine values were similar, serum osmolarity did not change at postoperative period in mannitol group and increased HS. Average intensive care and length of hospital stay were similar. Conclusion: In supratentorial tumor surgery, effective brain relaxation was achieved with Mannitol and HS, without affect to hemodynamics. Pulse pressure variability and PVI decreased with Mannitol. Blood gases, Na+, K+, BUN creatinine, osmolarity levels did not show serious changes. It was concluded that HS could be an alternative to mannitol in supratentorial surgery. Keywords: Hypertonic saline,mannitol, serum osmolarity, supratentorial tumor surgery

Evaluation of Hemodynamic Changes and Fluid Response during Anesthesia in Lumbar Disc Hernias with Pleth Variability Index (PVI).

The study aimed to assess the pleth variability index (PVI) in patients undergoing lumbar disc herniation surgery under general and spinal anesthesia, exploring its correlation with fluid responsiveness, position, and hemodynamic parameters. Methods: This prospective study included 88 ASA 1-2 patients, aged 18-65, undergoing 1-3 h elective lumbar disc herniation surgery. Patients in groups GA and SA were observed for demographic, operative, and hemodynamic parameters at specified time points. (3) Results: PVI values were comparable between the GA and SA groups. After 250 mL of fluid loading, both groups showed a significant decrease in basal PVI at T2. Prone positions in GA exhibited higher PI values than in SA. The transition from a prone to supine position maintained PVI, while pulse and MAP decreased.; (4) Conclusions: PVI values were comparable in elective lumbar disc herniation surgery with general and spinal anesthesia. Both groups exhibited significant a PVI decrease at T2 after 250 mL of fluid loading, indicating fluid responsiveness. In general anesthesia, the prone position showed a lower MAP and higher PI values compared to spinal anesthesia. PVI and PI, sensitive to general anesthesia changes, could have beneficial additions to standard hemodynamic monitoring in spinal anesthesia management.

Prognostic value of Pleth Variability Index in patients followed up in the Intensive Care Unit.

The Pleth Variability Index (PVI) can guide the approach to hypovolemia, which is sometimes the cause and sometimes the result of major diseases; further studies are needed on this index. Therefore, in the present study, we aimed to evaluate the prognostic value of PVI and its relationship with 28-day mortality. A total of 158 patients were included. Patients were divided into two groups according to 28-day mortality. Patients who died within 28 days were assigned to Group M (Mortal), while those who survived were included in Group S (Survive). Patients' demographics, definitive diagnosis, arterial blood pressure, fingertip oxygen saturation, PVI, fingertip blood glucose, fever, pulse, shock index, and serum lactate level were recorded. Regarding demographics, no statistically significant difference was found between the two groups in terms of age, gender, and Body Mass Index (BMI) (p=0.356, p=0.966, and p=0.977, respectively). The rate of intubation, the use of vasopressors, Acute Physiology and Chronic Health Evaluation (APACHE) II score, shock index, and PVI values were statistically significantly higher in Group M compared to Group S (for all, p<0.001). Glasgow Coma Score (GCS), Perfusion Index (PI), and length of stay were statistically significantly lower in Group M than in Group S (p<0.001, p<0.001, and p=0.025, respectively). PVI predicted 28-day mortality with 83.8% sensitivity and 97.9% specificity. PVI, serum lactate level, PI, APACHE II, GCS, and need for vasopressors were independent risk factors for 28-day mortality in the Intensive Care Unit (ICU). PVI and serum lactate have a prognostic value in predicting mortality.

Validation of Preload Assessment Technologies at Altitude in a Porcine Model of Hemorrhage

IntroductionDynamic preload assessment measures including pulse pressure variation (PPV), stroke volume variation (SVV), pleth variability index (PVI), and hypotension prediction index (HPI) have been utilized clinically to guide fluid management decisions in critically ill patients. These values aid in the balance of correcting hypotension while avoiding over-resuscitation leading to respiratory failure and increased mortality. However, these measures have not been previously validated at altitude or in those with temporary abdominal closure (TAC). MethodsForty-eight female swine (39 ± 2 kg) were separated into eight groups (n = 6) including all combinations of flight versus ground, hemorrhage versus no hemorrhage, and TAC versus no TAC. Flight animals underwent simulated aeromedical evacuation via an altitude chamber at 8000 ft. Hemorrhagic shock was induced via stepwise hemorrhage removing 10% blood volume in 15-min increments to a total blood loss of 40% or a mean arterial pressure of 35 mmHg. Animals were then stepwise transfused with citrated shed blood with 10% volume every 15 min back to full blood volume. PPV, SVV, PVI, and HPI were monitored every 15 min throughout the simulated aeromedical evacuation or ground control. Blood samples were collected and analyzed for serum levels of serum IL-1β, IL-6, IL-8, and TNF-α. ResultsHemorrhage groups demonstrated significant increases in PPV, SVV, PVI, and HPI at each step compared to nonhemorrhage groups. Flight increased PPV (P = 0.004) and SVV (P = 0.003) in hemorrhaged animals. TAC at ground level increased PPV (P < 0.0001), SVV (P = 0.0003), and PVI (P < 0.0001). When TAC was present during flight, PPV (P = 0.004), SVV (P = 0.003), and PVI (P < 0.0001) values were decreased suggesting a dependent effect between altitude and TAC. There were no significant differences in serum IL-1β, IL-6, IL-8, or TNF-α concentration between injury groups. ConclusionsBased on our study, PPV and SVV are increased during flight and in the presence of TAC. Pleth variability index is slightly increased with TAC at ground level. Hypotension prediction index demonstrated no significant changes regardless of altitude or TAC status, however this measure was less reliable once the resuscitation phase was initiated. Pleth variability index may be the most useful predictor of preload during aeromedical evacuation as it is a noninvasive modality.

Pleth variability index during preoxygenation could predict anesthesia-induced hypotension: A prospective, observational study

Study objectiveTo determine whether changes in the pleth variability index (PVi) during preoxygenation with forced ventilation for 1 min could predict anesthesia-induced hypotension. DesignProspective, observational study. SettingA tertiary teaching hospital. PatientsNinety-six patients who underwent general anesthesia using total intravenous anesthesia were enrolled. InterventionsUpon the patient's arrival at the preoperative waiting area, a PVi sensor was affixed to their fourth fingertip. For preoxygenation, forced ventilation of 8 breaths/min in a 1:2 inspiratory-expiratory ratio was conducted using the guidance of an audio file. One minute after preoxygenation, anesthetic administration was initiated. Blood pressure was measured for the next 15 min. MeasurementsWe calculated the difference (dPVi) and percentage of change (%PVi) between the PVi values immediately before and after forced ventilation. Anesthesia-induced hypotension was defined as a mean arterial pressure of <60 mmHg within 15 min after the infusion of anesthetics. Main resultsOverall, 87 patients were included in the final analysis. Anesthesia-induced hypotension occurred in 31 (35.6%) of the 87 patients. Receiver operating characteristic curve analyses identified a cut-off value of −2 for dPVi, with an area under the curve of 0.691 (95% confidence interval [CI], 0.564–0.818; P < 0.001) and a cut-off value of −7.6% for %PVi, with an area under the curve of 0.711 (95% CI, 0.589–0.832; P < 0.001). Further, multivariate logistic regression analysis showed that a low %PVi with an odds ratio of 9.856 (95% CI, 3.131–31.032; P < 0.001) was a significant determinant of anesthesia-induced hypotension. ConclusionsHypotension frequently occurs during general anesthesia induction and can impact outcomes. Additionally, the percentage change in the PVi before and after preoxygenation using deep breathing can be used to predict anesthesia-induced hypotension.

Are the perfusion İndex and pleth variability index title an early İndicator of brachial plexus block?

Studies on the evaluation of the Perfusion Index (PI) and the Pleth Variability Index (PVI) and the success of PI and PVI block in patients undergoing brachial plexus are limited and quite inadequate. In our study, we aimed to compare PI and PVI between the interscalen block and infraclavicular block and evaluate its use as an early marker in block success. Single-center prospective randomized controlled trials. Preoperative unit, operating room. Patients over 18 years of age who have had upper extremity surgery. Brachial plexus block (interscalene, infraclavicular). Demographic data, Hemodynamic parameters, Perfusion index and Pleth Variability Index. 40 patients, including ASA1-2, 20 patients over the age of 18, who were planned for upper extremity surgery, in the interscalen group, and 20 in the supraclavicular group, were included in the study. Demographic data of the patients were recorded by measuring PI and PVI values at baseline before the block and at the 1st, 5th, 10th, 15th, and 20th minutes after the block, both simultaneously. 62.5% (n = 25) of the patients included in the study were female. The mean age of the patients was detected as 52.63 ± 16.472, the mean BMI as 26.57 ± 4.423, and the mean entry hemoglobin level as 13.71 ± 1.87 g/dL. The hemodynamic data of the groups were similar across the time periods. The increase in PI increased significantly after 1 minute in both groups. The PVI was similar between the groups at all measurement times. In our study, we observed an increase in PI from the 1st minute compared to the non-blocked arm in successful block applications. We consider the early indicator of PI in the evaluation of block success. In our study, we did not observe a significant change in the arm that was blocked and the arm that was not treated with PVI.

The effects of body weight and pneumoperitoneum on pleth variability index and total haemoglobin in patients undergoing laparoscopic cholecystectomy: A prospective observational study

It is not clear if there is an inaccurate effect of obesity and pneumoperitoneum on non-invasive monitoring parameters. The aim of this study is to determine the effects of CO2 pneumoperitoneum and desufflation on non-invasive monitoring variables between obese and non-obese patients undergoing laparoscopic surgery. Sixty patients were included in the study that underwent laparoscopic cholecystectomy between February 2019 and November 2019. After induction of anaesthesia, systolic and diastolic blood pressures, heart rate, duration of operation and pneumoperitoneum, pleth variability index (PVI) and total hemoglobin (SpHb) data were recorded. The patients were divided into two groups. There was no significant difference between the groups in terms of chronic diseases and duration of operation and pneumoperitoneum. No significant difference was found between the groups in PVI and SpHb values. In comparison of PVI measurement values with T0, a significant difference was found in T3, T4 and T5 in Group 2 (p = 0.010, 0.012 and 0.041, respectively). In comparison of SpHb measurement values with T0, a significant difference was found in T1, T2 and T3 in Group 2 (p = 0.008, 0.010 and 0.037, respectively). In comparison with T5, a significant difference was found in T1, T2 and T3 in Group 2 (p = 0.023, 0.005 and 0.006, respectively). In obese people, pneumoperitoneum can lead to errors in PVI and SpHb monitoring. Although these two parameters are very valuable in intraoperative follow-up, they should be used carefully during laparoscopic procedures in obese patients. If these parameters (PVI and SpHb) are considered to be used in bariatric surgeries, this information should be considered.

Use of the pleth variability index in children with obstructive respiratory disease

IntroductionThe phenomenon of pulsus paradoxus (PP) develops at varying rates in relation to the severity of the disease in obstructive respiratory tract disease. The Pleth Variability Index (PVI) is the measurement value of perfusion index changes that occur with ventilation, which are determined during at least one respiratory cycle. Therefore, noninvasive measurement of PVI can help in the measurement of PP. The current study aims to determine the role of PVI measurements before and after bronchodilator therapy during admission to the hospital in children with obstructive respiratory tract disease. MethodsAge, gender, Pulmonary Index Score (PIS), and PVI data of patients aged 2–18 years who applied to the pediatric emergency department with signs of obstructive respiratory tract disease were recorded in triage. The PVI and PIS scores of the patients, who were divided into three groups according to their clinical severity scores, were recorded before and after bronchodilator treatment, and they were compared to the PVI values according to the disposition results. ResultsA total of 133 patients were included in this prospective, single-center study. The PVI values before and after treatment were significantly higher in patients with severe disease compared to the mild and moderate groups (p < 0.001). Post-treatment PVI values were significantly lower than pre-treatment values in all clinical severity groups (p < 0.001). While a total of 95 (71.43%) patients were discharged from the emergency department, 31 (23.31%) patients were admitted to the relevant department, and seven (5.26%) patients were admitted to the pediatric intensive care unit. The PVI values before and after treatment were significantly higher in the hospitalized group compared to the group discharged from the emergency department (p < 0.001). The areas under the ROCs were 0.940, 0.865, and 0.843 for the PVI measurements in patients with severe disease, moderate disease, and hospitalization (p< 0.001). ConclusionsAutomated PVI measurement can be used as a noninvasive, rapid, and objective tool in the emergency department triage of patients admitted to the pediatric emergency department with signs of asthma attack or reactive respiratory tract disease.

Transüretral Prostat Rezeksiyonlarında İntravasküler Volüm Durumunun Dalga Değişkenlik İndeksi ile Değerlendirilmesi

Objective: Patients with benign prostatic hypertrophy (BPH) are treated with transurethral resection of the prostate (TURP). The passage of irrigation fluid into the systemic circulation can cause hypervolemia, hyponatremia and due to them TURP syndrome with restlessness, confusion, dyspnea, arrhythmia and seizures. The most important point is early diagnosis. Our aim was to reveal the statistical relationship between serum sodium (Na) values and the pleth variability index (PVI) in patients who underwent TURP. Methods: Thirty-three ASA I-III and 40-80 years old patients who underwent TURP under spinal anesthesia were included in the study. The patients were taken to the operating room and standard monitoring was applied. Venous blood samples were taken from the peripheral vascular access before and after the procedure, and Na values were determined; PVI values were recorded at 5-minute intervals from the preoperative period to the postoperative period by performing PVI monitoring. Results: The PVI data correlated with postoperative osmolarity, postoperative Na concentration, resection time and irrigation amount as an early predictor of hypervolemia and seconder hyponatremia. Conclusion: We think that more comprehensive case studies are needed in terms of the usability of PVI, which is a noninvasive method compared to blood gas sampling, an invasive method for the diagnosis of hypervolemia and hyponatremia, and that continuous monitoring and follow-up provide an advantage in early diagnosis. Keywords: Pleth variability index, benign prostatic hypertrophy, TURP, osmolarity, amount of irrigation

The use of Pleth Variability Index (PVI) for the assessment of patients with dehydration in the pediatric emergency department

Objective: There is not a non-invasive, valid, and reliable criterion yet that can be used to determine the degree of dehydration and responsiveness to fluid treatment. In the literature, Pleth Variability Index (PVI) has been studied as one of the additional tools that can be used to determine the degree of dehydration. Studies on this topic have been conducted mainly on patients who are connected to mechanical ventilators. This study was conducted to assess the feasibility of PVI measurement in paediatric patients who breathe spontaneously, are dehydrated moderately and need fluid repletion. Material and Methods: For this purpose, PVI, blood gas (pH, HCO3, lactate), and body weights of the patients were measured before and after fluid replacement. The delta (Δ) values were calculated by taking the difference between the values before and after fluid therapy, and the correlation was examined. Results: After one hour of fluid treatment, weight, physical examination, blood gas (bicarbonate, lactate, pH) values improved significantly compared to pre-fluid levels, and high PVI values were found to decrease significantly. However, no significant correlation was found between PVI change (ΔPVI) and other variables (Δ kilo, pH, lactate, bicarbonate), which are used to determine the degree of dehydration. Conclusion: According to the findings of our study, PVI alone does not provide adequate and reliable data in children who are dehydrated moderately and breathe spontaneously

The correlation between Corrected Flow Time (FTc) Based on Esophageal Doppler Monitoring and Pleth Variability Index (PVI) in the Fluid Therapy in Patients undergoing Total Abdominal Hysterectomy

Background: The occurrence of bleeding during major surgeries is common and requires timely and accurate management in the prevention and treatment of hypovolemia and hemodynamic instability during and after surgery. This study evaluated the correlation and agreement between the two protocols determining the status of the hypovolemia during hysterectomy. Methods: This study was a randomized single-blinded clinical trial. The study population included 30 patients undergoing Total Abdominal Hysterectomy in Shariati Hospital in Tehran between 2015 and 2016. The patients were randomly assigned to two groups using a randomized table of numbers, so that in the FTc group, fluid therapy was performed based on the FTc index and in the PVI group based on the PVI index. The changes in FTc and PVI values were recorded every 5 minutes and the changes in the two indicators from the beginning to the end of the treatment were evaluated. At the beginning and end of the surgery, an arterial blood gas analysis (ABG) was also performed. The amount of bleeding during operation and urinary output were recorded in two groups. Results: There was no significant difference across the two groups in total fluid intake during surgery, mean volume of blood loss, mean urine output, and duration of surgery. The arterial blood gas status was also similar in both groups at the beginning and the end of the operation. We found a strong adverse correlation between FTC and PVI indices at the different time points evaluated within the surgery. In total, there was a strong correlation between the mean FTC and the mean PVI during the first hour (r=-0.765, P &lt; 0.001) and the second hour (r=-0.941, -P &lt; 0.001) of operation. Considering the cut-off point of 350msec for the FTC and 13% for the PVI in predicting hypovolemia, the agreement between the two protocols in fluid therapy during the first hour after surgery was 79.8% and 76.6%. Conclusion: There is a strong and significant correlation between the two FTC (with a cut off of 350) and PVI (with a cut point of 13%) to predict need for fluid therapy.

The Efficacy of Inferior Vena Cava Diameter, Perfusion Index and Pleth Variability Index on Predicting Hypotension in Spinal Anesthesia

Objective: One of the most common side effects of spinal anesthesia (SA) is hypotension. The aim of the study was to evaluate the efficacay of inferior vena cava (IVC) diameter measurements, perfusion index (PI) and pleth variability index (PVI) values in determining the risk of developing hypotension after SA. Materials and Methods: This study was conducted on 81 patients who underwent transurethral prostatectomy. Before administration of SA, PI and PVI values, IVC diameters (IVCmin: during inspiration and IVCmax: during expiration) and IVC collapsibility index (IVCCI) values and non-invasive blood pressure were recorded. Patients with a baseline systolic arterial pressure reduction rate of ≥25% were determined as the group developing hypotension. IVC diameter measurements were measured immediately after SA then 5 min, and at the end of the operation. The heart rate, mean arterial pressure, PI and PVI values were recorded at regular intervals. Results: Hypotension occured in 32 patients (39.5%). In the hypotensive group, IVCmax and IVCmin values were observed lower and IVCCI values higher. The optimal threshold value of IVCmin was ≤0.99 and threshold value of IVCCI was &gt;%44.5 for predicting hypotension after SA. Conclusion: While IVCmin and IVCCI values were effective in determining hypotension risk after SA, PI and PVI values were not. To predict hypotension by IVC diameter measurements after SA will allow a more effective intervention and avoid hypotension.

The use of oxygen reserve index in one-lung ventilation and its impact on peripheral oxygen saturation, perfusion index and, pleth variability index

BackgroundOur goal is to investigate the use of the oxygen reserve index (ORi) to detect hypoxemia and its relation with parameters such as; peripheral oxygen saturation, perfusion index (PI), and pleth variability index (PVI) during one-lung ventilation (OLV).MethodsFifty patients undergoing general anesthesia and OLV for elective thoracic surgeries were enrolled in an observational cohort study in a tertiary care teaching hospital. All patients required OLV after a left-sided double-lumen tube insertion during intubation. The definition of hypoxemia during OLV is a peripheral oxygen saturation (SpO2) value of less than 95%, while the inspired oxygen fraction (FiO2) is higher than 50% on a pulse oximetry device. ORi, pulse oximetry, PI, and PVI values were measured continuously. Sensitivity, specificity, positive and negative predictive values, likelihood ratios, and accuracy were calculated for ORi values equal to zero in different time points during surgery to predict hypoxemia. At Clinicaltrials.gov registry, the Registration ID is NCT05050552.ResultsHypoxemia was observed in 19 patients (38%). The accuracy for predicting hypoxemia during anesthesia induction at ORi value equals zero at 5 min after intubation in the supine position (DS5) showed a sensitivity of 92.3% (95% CI 84.9–99.6), specificity of 81.1% (95% CI 70.2–91.9), and an accuracy of 84.0% (95% CI 73.8–94.2). For predicting hypoxemia, ORi equals zero show good sensitivity, specificity, and statistical accuracy values for time points of DS5 until OLV30 where the sensitivity of 43.8%, specificity of 64%, and an accuracy of 56.1% were recorded. ORi and SpO2 correlation was found at DS5, 5 min after lateral position with two-lung ventilation (DL5) and at 10 min after OLV (OLV10) (p = 0.044, p = 0.039, p = 0.011, respectively). Time-dependent correlations also showed that; at a time point of DS5, ORi has a significant negative correlation with PI whereas, no correlations with PVI were noted.ConclusionsDuring the use of OLV for thoracic surgeries, from 5 min after intubation (DS5) up to 30 min after the start of OLV, ORi provides valuable information in predicting hypoxemia defined as SpO2 less than 95% on pulse oximeter at FiO2 higher than 50%.

Relationship between Pleth Variability Index and the Occurrence of Hypotension during Epidural Anesthesia for Cesarean Section.

To determine the predictive effect of pleth variability index（PVI）before anesthesia on hypotension after epidural anesthesia in cesarean section parturient women. Observational study. GansuProvincePeople'sHospital, China, from March 2019 to May 2020. One hundred and seven singleton parturient women, who underwent elective cesarean section, were selected. They were divided into no hypotension group (Group A) and hypotension group (Group B). Hypotension was defined as systolic blood pressure lower than 90 mmHg or >30% decrease in the mean arterial pressure. Receiver operating characteristic (ROC) curve was used to evaluate the predictive value of PVI before anesthesia and heart rate (HR) for hypotension after epidural anesthesia. After epidural anesthesia, 41 (38.32%) parturient women had hypotension. Basic values of HR and PVI before anesthesia in Group B were significantly higher than Group A (both p <0.001). The area under the ROC curve (AUC) of PVI basic value predicting hypotension was 0.824 (95% CI: 0.746-0.903, p <0.001), was greater than the AUC of HR basic value predicting hypotension, and the sensitivity and specificity of predicting hypotension were 92.7% and 66.7%, respectively. The PVI and HR values before anesthesia have certain value in predicting hypotension after epidural anesthesia in cesarean section. PVI value before epidural anesthesia has more clinical significance than the HR. Key Words: Pleth variability index (PVI, Heart rate (HR), Epidural anesthesia, Cesarean, Hypotension.

Assessment of pleth variability index in volume changes during ultrafiltration process.

OBJECTIVES:Pleth variability index (PVI) has been studied mostly in mechanically ventilated patients, and the role of PVI in predicting volume status and volume changes among spontaneously breathing patients is not clear in the literature. We hypothesized that hemodialysis (HD) can be a valid model for a simulation that can be evaluated the correlation of PVI with fluid changes in various volume states. The aim of this study was to investigate the utility of PVI for assessing volume changes in HD patients who are breathing spontaneously.METHODS:This prospective, observational study included patients aged 18 years or older who had end-stage renal failure and presented for routine HD between December 2019 and January 2020. PVI values were measured before and after HD session. Changes in PVI levels were compared according to the amount of ultrafiltration.RESULTS:A total of sixty patients were included. Mean PVI level before HD (20.7% ± 5%) showed a statistically significant increase to 27.7% ± 6% after HD session (P < 0.001). According to the amount of fluid removed during HD, the changes in PVI were statistically significant (P = 0.015). There was a strong correlation between ΔPVI and ultrafiltrated volume (r = 0.744, P < 0.001).CONCLUSION:The fluid removed by HD caused increase in PVI, and the increase was strongly correlated with the amount of volume change. Bedside monitoring of PVI may provide the clinicians with useful information for monitoring the volume status in critically ill patients with spontaneous breathing.

The predictive value of the Pleth Variability Index on fluid responsiveness in spontaneously breathing anaesthetized children-A prospective observational study.

BackgroundIn children, the preoperative hydration status is an important part of the overall clinical assessment. The assumed preoperative fluid deficit is often routinely replaced during induction without knowing the child's actual fluid status.AimWe investigated the predictive value of the Pleth Variability Index as a measure of fluid responsiveness in spontaneously breathing anesthetized children.MethodsPleth Variability Index, stroke volume and Cardiac Index, measured by electrovelocimetry, mean blood pressure, and heart rate were recorded during anesthesia induction in 50 pediatric patients <6 years. Baseline values were compared to values recorded after administration of 10 mL/kg of Ringer's lactate and during two passive leg raising tests (before and after fluid administration). Fluid responsiveness was defined as an increase of ≥10% in stroke volume.ResultsOnly in fluid responsive patients, Pleth Variability Index values were higher before fluid administration than thereafter (21.4 ± 5.9% vs 15.0 ± 9.4%, 95% CI of difference 1.1 to 11.8%, P = .02). Pleth Variability Index values at baseline were higher in fluid responders (21.4 ± 5.9%) than in fluid nonresponders (15.3 ± 7.7%), 95% CI of difference 1.6 to 10.6%, P = .009. The area under the receiver operating curve indicating fluid responsiveness was 0.781 (95% CI 0.623 to 0.896, P = .0002), with the highest sensitivity (82%) and specificity (70%) at a Pleth Variability Index of >15% (Positive predictive value 2.71 (95% CI: 1.4 to 5.2)). Only in fluid responders, the Pleth Variability Index decreased during passive leg raising, while stroke volume increased.ConclusionsThe Pleth Variability Index may be of additional value to predict fluid responsiveness in spontaneously breathing anesthetized children. A significant overlap in baseline Pleth Variability Index values between fluid responsive and nonfluid responsive patients does not allow a reliable recommendation as to a cut off value.

This Month in Anesthesiology

This Month in Anesthesiology

The effects of pneumoperitoneum and patient position on the perfusion index and pleth variability index during laparoscopic bariatric surgery

Objective: Limited data are available on the use of the perfusion index (PI) and the pleth variability index (PVI) during laparoscopicbariatric surgery. We investigated the effects of pneumoperitoneum and the reverse Trendelenburg position on these indices.Materials and Methods: PI, PVI, heart rate (HR), blood pressure, SpO2 and ventilation parameters were recorded before anaesthesiainduction (T0), 5 min after endotracheal intubation (T1), immediately before surgery, after the patient had been in the reverseTrendelenburg position for 5 min (T2), after inflating the abdomen with CO2 in reverse Trendelenburg (T3), after the abdomen hadbeen deflated (T4) and 5 min after extubation (T5).Results: General anaesthesia induced an increase in the PI (P&amp;lt;.001), and a decrease in the PVI (P=.002). The PI and PVI values werenot affected during T2 or T3. Pneumoperitoneum caused an increase in mean arterial pressure (MAP) and a decrease in HR. PVI andMAP decreased during T4, but the PI and HR remained unchanged. PVI, HR and MAP increased during T5.Conclusion: Our data suggest that the reverse Trendelenburg position and pneumoperitoneum did not affect the PI or PVI values,whereas deflation decreased the PVI in morbidly obese patients under general anaesthesia.

The Effect of Surgical Patient Positions on Plet Variability Index, Perfusion Index and Noninvasive Continuous Cardiac Output Measurement Method in Voluntary Breathing Volunteers

Amaç: Cerrahi prosedür için verilen farklı pozisyonlar doku perfüzyonunda ve kardiyak outputta değişikliklere neden olabilir. Bu çalışmada spontan solunuma sahip katılımcılarda plet değişkenlik indeksinin (PVI), perfüzyon indeks (PI) ve noninvaziv sürekli kardiyak output ölçüm yöntemi (EscCO) nin farklı cerrahi pozisyonlardaki değişimlerini araştırmayı amaçladık.Materyal ve Metod: 20 katılımcıdan oluşan bir sağlıklı birey grubu prospektif gözlemsel çalışmaya dahil edildi. Sırasıyla Supin, 30 derece baş yukarı, 45 derece baş yukarı, 20 derece Trendelenburg, 20 derece ters-Trendelenburg, ve pron pozisyonları uygulandı. Her pozisyon arası 10 ar dk olacak şekilde süre tutuldu. Her pozisyon değişikliğinden önce gönüllüler sırtüstü pozisyona alındı ve beş dakika dinlendikten sonra yeni pozisyon verildi. Pozisyon değişiminden sonraki 5. dakika PI, PVI, EscCO, SpO2 değerleri kayıt altına alındı.Bulgular: Katılımcıların farklı pozisyondayken ölçülen PI, PVI ile EscCO değerlerinde istatistiksel olarak anlamlı bir fark bulunamadı.Sonuç: Bu çalışma, PI, PVI ile EscCO nun tüm cerrahi pozisyonlarda herhangi bir değişikliğe uğramadığını ve her üç parametrenin de spontan solunumuna sahip genç sağlıklı bireylerde pozisyondan etkilenmediği ortaya koymuştur.

Pleth variability index or stroke volume optimization during open abdominal surgery: a randomized controlled trial

BackgroundThe impact of Goal Directed Fluid Therapy (GDFT) based on the non-invasive Pleth Variability Index (PVI) on clinical outcome after abdominal surgery has only sparingly been explored. The purpose of this study was to compare the effect of intraoperative GDFT guided by PVI to a control group using esophageal Doppler on the incidence of complications and length of hospital stay after major abdominal surgery. We hypothesized that there would be no difference between the groups.MethodsThis was a randomized controlled trial in a Swedish university hospital between November 2011 and January 2015; 150 patients scheduled for open abdominal surgery lasting 2 h or more were included. Exclusion criteria included hepatic resection or severe cardiac arrhythmia. The patients were randomized 1:1 to either the intervention group or the control group. The intervention group received intraoperative GDFT by administering fluid boluses of 3 ml/kg tetrastarch aiming at a PVI value below 10%, while GDFT in the control group aimed for optimization of stroke volume as assessed with esophageal Doppler. Blinded observers assessed complications until postoperative day 30 using pre-defined definitions, as well as length of hospital stay.ResultsOne hundred and-fifty patients were randomized and 146 patients were available for the final data analysis. Median duration of surgery was 3 h. A total of 64 complications occurred in the PVI group (N = 74) and 70 in the Doppler group (N = 72) (p = 0.93). Median (IQR) length of stay was 8.0 (8.0) days in the PVI group and 8.0 (9.5) in the Doppler group (P = 0.57).ConclusionsNo difference in clinical outcome, as defined by number of postoperative complications, and length of hospital stay, was found when goal directed fluid therapy was applied using PVI as an alternative to esophageal Doppler. PVI appears to be an acceptable alternative to esophageal Doppler for goal directed fluid therapy during major open abdominal surgery.Trial registrationClinicaltrials.gov NCT01458678. Date of first registration October 20, 2011.