deadspace_total: Estimate ventilation dead-space

In jackwasey/physiology: Calculate physiologic characteristics of awake and anesthetized adults, children and infants

Estimate ventilation dead-space

Description

Estimate ventilation dead-space

Usage

deadspace_total(
  ideal_weight_kg,
  age_y = NULL,
  elbow_ml = 10,
  humidifier_ml = 7,
  ett_diameter_mm = NULL
)

deadspace_anatomic(ideal_weight_kg, age_y = NULL)

deadspace_anatomic_adult(ideal_weight_kg = NULL)

deadspace_anatomic_child(ideal_weight_kg, age_y = NULL)

deadspace_intrathoracic_ml(ideal_weight_kg)

Arguments

ideal_weight_kg	Ideal weight in kilograms. May be calculated using ideal_weight_adult or ideal_weight_child
age_y	Age in years, optional for estimating ETT and HME sizes automatically
elbow_ml	Numeric volume of elbow of breathing circuit in ml
humidifier_ml	Numeric volume of humidifier of breathing circuit in ml
ett_diameter_mm	Numeric internal diameter of endotracheal tube. Default is NULL which would estimate this from the age of patient

Details

'Mean intrathoracic anatomic dead space was 1.03 ml/kg and was not related to age.' Numa, 1985

Value

estimate of anatomic dead-space in ml

Functions

• deadspace_anatomic(): Estimate anatomic dead-space

• deadspace_anatomic_adult(): Estimate anatomic dead-space in an adult

• deadspace_anatomic_child(): Estimate anatomic dead-space in an infant or child

• deadspace_intrathoracic_ml(): intrathoracic component of dead-space is age independent

References

http://www.atsjournals.org/doi/abs/10.1164/arrd.1971.104.2.215 http://rc.rcjournal.com/content/53/7/885.short https://www.ncbi.nlm.nih.gov/pubmed/8727530

See Also

Other respiratory: alveolar_PAO2_mmHg()

Other airway equipment: deadspace_things_ml, ett_size_by_age(), ett_vol_ml()

Examples

  height <- seq(1, 2, 0.05)
  male <- rep(FALSE, length(height))
  iw <- ideal_weight_adult(height_m = height, male = male)
  ## Not run: 
  plot(iw, deadspace_anatomic_adult(ideal_weight_kg = height))
  
## End(Not run)

  # discontinuity at age 6 is driven by ideal weight more than the
  # lograithmic calculation
  iw <- c(seq(12, 18, 0.2), seq(18.5, 24, 0.5))
  youngest = 3
  oldest = 9
  ages <- seq(youngest, oldest, (oldest - youngest) / (length(iw) - 1))
  ## Not run: 
  plot(iw, deadspace_anatomic_child(ideal_weight_kg = iw, age_y = ages),
       type = "l")
  
## End(Not run)

jackwasey/physiology documentation built on March 19, 2024, 6:31 a.m.