Tidal Volume, Predicted Body Weight, and Modes of Mechanical Ventilation

Background: Patients under mechanical ventilation are at risk of ventilator-associated complications. One of these complications is lung injury due to high tidal volume. Nurses’ competence in mechanical ventilation is critical for preventing ventilator-associated complications. This study assessed the effects of feedback and education on nurses’ clinical competence in mechanical ventilation and accurate tidal volume setting. Methods: This single arm pretest-post-test interventional study was conducted in 2019 at Shariati hospital affiliated to Tehran University of Medical Sciences. Participants were 75 conveniently selected nurses. Initially, nurses’ clinical competence in mechanical ventilation and ventilator parameters of 250 patients were assessed. A mechanical ventilation -based feedback and education intervention was implemented for nurses. Finally, mechanical ventilation clinical competence of nurses and ventilator parameters of 250 new patients were assessed. Moreover, patients’ height was estimated based on their ulna length and then, their predicted body weight was calculated using their estimated height. Accurate tidal volume was determined per predicted body weight. Results: The mean score of nurses’ clinical competence increased from 8.27±3.09 at pretest to 10.07±3.34 at post-test (p<0.001). The mean values of both total tidal volume and tidal volume per kilogram of predicted body weight were significantly reduced respectively from 529.84±69.11 and 9.11±1.73 (ml) at pretest to 476.30±31.01 and 7.79±1.14 (ml) at post-test (p<0.001). Conclusion: The feedback and education intervention is effective in promoting nurses’ clinical competence in mechanical ventilation and reducing tidal volume. Thereby, it can reduce lung injuries associated with high tidal volume and ensure patient safety.

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A Higher Tidal Volume May Be Used for Athletes according to Measured FVC

The Scientific World JOURNAL ◽

10.1155/2013/526138 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Pavlos Myrianthefs ◽

George Baltopoulos

Keyword(s):

Mechanical Ventilation ◽

Body Weight ◽

Tidal Volume ◽

Vital Capacity ◽

Professional Athletes ◽

Normal Lung ◽

Predicted Body Weight ◽

Lung Volumes ◽

Males And Females ◽

The Difference

We investigated whether professional athletes may require higher tidal volume (Tv) during mechanical ventilation hypothesizing that they have significantly higher “normal” lung volumes compared to what was predicted and to nonathletes. Measured and predicted spirometric values were recorded in both athletes and nonathletes using a Spirovit SP-1 spirometer (Schiller, Switzerland). NormalTv(6 mL/kg of predicted body weight) was calculated as a percentage of measured and predicted forced vital capacity (FVC) and the difference (δ) was used to calculate the additionalTvrequired using the equation: NewTv(TvN)=Tv+(Tv×δ). Professional athletes had significantly higher FVC compared to what was predicted (by 9% in females and 10% in males) and to nonathletes. They may also require aTvof 6.6 mL/kg for males and 6.5 mL/kg for females during mechanical ventilation. Nonathletes may require aTvof 5.8 ± 0.1 mL/kg and 6.3 ± 0.1 mL/kg for males and females, respectively. Our findings show that athletes may require additionalTvof 10% (0.6/6 mL/kg) for males and 8.3% (0.5/6 mL/kg) for females during general anesthesia and critical care which needs to be further investigated and tested.

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Accurate Tidal Volume for Patients under Mechanical Ventilation: A Cross-sectional Descriptive Study

Archives of Anesthesia and Critical Care ◽

10.18502/aacc.v6i4.4631 ◽

2020 ◽

Author(s):

Leila Sayadi ◽

Shahrzad Ghiyasvandian ◽

Ali Karimi Rozveh ◽

Samira Norouzrajabi

Keyword(s):

Mechanical Ventilation ◽

Body Weight ◽

Lung Injury ◽

Tidal Volume ◽

Improve Patient Safety ◽

Descriptive Study ◽

Predicted Body Weight ◽

Volume Determination ◽

Cross Sectional ◽

Nurses Knowledge

Background: In order to prevent lung injury among patients under mechanical ventilation, tidal volume should be determined based on predicted body weight. The aim of the study was to determine the accuracy of tidal volume determination for patients under mechanical ventilation and to assess nurses’ knowledge about accurate tidal volume determination. Methods: This was a cross-sectional descriptive study. This study was conducted on 250 patients under mechanical ventilation and 75 nurses who provided care to the patients. Patients’ height was estimated based on their ulna length and then, their predicted body weight and tidal volume were estimated. Nurses’ knowledge about tidal volume determination was also assessed. Results: The mean of delivered tidal volume was 9.1±1.73 mL/kg of predicted body weight. Tidal volume for 172 patients (68.8%) had been set at more than 8 mL/kg of predicted body weight. Forty nine nurses (65.3%) noted that there was no guideline in their wards for height and weight measurement. They determined patients’ weight and height through either visual estimation (21 nurses; 28.0%) or asking from their colleagues, patients, or patients’ family members (48 nurses; 64.0%). Conclusion: Nurses have limited knowledge about accurate tidal volume determination and hence, deliver high tidal volume to patients under mechanical ventilation which puts them at risk for ventilator-associated lung injury. Urgent interventions such as lung-protective strategies, staff training, and careful managerial supervision are needed to prevent ventilator-associated lung injury and improve patient safety.

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Tidal Volume in Mechanical Ventilation: The Importance of Considering Predicted Body Weight

American Journal of Respiratory and Critical Care Medicine ◽

10.1164/ajrccm.178.3.315 ◽

2008 ◽

Vol 178 (3) ◽

pp. 315-316 ◽

Cited By ~ 1

Author(s):

Andreas Günther ◽

Friedemann Taut

Keyword(s):

Mechanical Ventilation ◽

Body Weight ◽

Tidal Volume ◽

Predicted Body Weight

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Standardizing Predicted Body Weight Equations for Mechanical Ventilation Tidal Volume Settings

CHEST Journal ◽

10.1378/chest.14-2843 ◽

2015 ◽

Vol 148 (1) ◽

pp. 73-78 ◽

Cited By ~ 23

Author(s):

Olinto Linares-Perdomo ◽

Thomas D. East ◽

Roy Brower ◽

Alan H. Morris

Keyword(s):

Mechanical Ventilation ◽

Body Weight ◽

Tidal Volume ◽

Predicted Body Weight

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Tidal Volume in Mechanical Ventilation: The Importance of Considering Predicted Body Weight

American Journal of Respiratory and Critical Care Medicine ◽

10.1164/ajrccm.178.3.316 ◽

2008 ◽

Vol 178 (3) ◽

pp. 316-316

Author(s):

Andrés Esteban ◽

Fernando Frutos-Vivar ◽

Niall D. Ferguson ◽

Antonio Anzueto

Keyword(s):

Mechanical Ventilation ◽

Body Weight ◽

Tidal Volume ◽

Predicted Body Weight

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Assessment of Fluid Responsiveness After Tidal Volume Challenge During Pressure-Controlled Ventilation Volume Guaranteed: An observational study

10.21203/rs.3.rs-45075/v1 ◽

2020 ◽

Author(s):

Yu Jiang ◽

Lingling Jiang ◽

Jun Hu ◽

Ye Zhang

Keyword(s):

Body Weight ◽

Tidal Volume ◽

Fluid Responsiveness ◽

Transient Increase ◽

Anesthesia Induction ◽

Predicted Body Weight ◽

Controlled Ventilation ◽

Pressure Controlled Ventilation ◽

Pressure Controlled ◽

Volume Challenge

Abstract Background: The reliability of pulse pressure variation (PPV) and stroke volume variation (SVV) to predict fluid responsiveness have not previously been established when using pressure-controlled ventilation-volume guaranteed (PCV-VG) mode. We hypothesized that with a transient increase in tidal volume from 6 to 8 mL/kg of predicted body weight (PBW), which we reference as the “tidal volume challenge (TVC)”, the changes to PPV and SVV will be an indicator of fluid responsiveness.Methods: The patients were first ventilated with a tidal volume of (Vt) 6 mL/kg of predicted body weight (PBW) using PCV-VG. Following intravenous anesthesia induction, PPV6 and SVV6 were recorded, then the TVC was performed, which increased Vt from 6 mL/kg to 8 mL/kg PBW for 1 minute and PPV8 and SVV8 were recorded again. The changes in value of PPV and SVV (ΔPPV6-8 and ΔSVV6-8) were calculated after TVC. Following the minute of TVC, the tidal volume was returned to 6 ml/kg PBW for the fluid challenge (FC), a colloid infusion of 6ml/kg PBW for 20 minutes. Patients were classified as responders if there was an increase in cardiac index (CI) of more than 15% after FC, otherwise the patients were identified as non-responders. Eligible patients were divided into groups of responders or non-responders.Results: 37 patients were classified as responders and 44 were non-responders. PPV6 and SVV6 could not predict the fluid responsiveness, while PPV8 and SVV8 could predict the fluid responsiveness when using PCV-VG mode. The changes in value of PPV and SVV after TVC (ΔPPV6-8 and ΔSVV6-8) identified true fluid responders with the highest sensitivity and specificity in the above variables, which predicted fluid responsiveness with the area under the receiver operating characteristic curves (AUCs) (95% CIs) being 0.96 (0.93-1.00) and 0.98 (0.96-1.00), respectively. No significant difference was found when comparing the AUCs of ΔPPV6-8 and ΔSVV6-8 (P > 0.05). Linear correlation was represented between the change value of CI after FC and the change value of SVV or PPV after TVC (r = 0.68; P < 0.0001 and r = 0.77; P < 0.0001, respectively).Conclusions: A transient increase in tidal volume, which we reference as the “tidal volume challenge (TVC)” could enhance the predictive value of PPV and SVV for the evaluation of fluid responsiveness in patients under ventilation with PCV-VG.Trial registration: Chinese Clinical Trial Registry (ChiCTR2000028995). Prospectively registered on 11 January 2020. http://www.medresman.org.

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