phoenix (version 1.1.3)

phoenix_respiratory: Phoenix Respiratory Score

Description

Apply the Phoenix Respiratory Scoring rubric to a data set. The respiratory score is part of the diagnostic Phoenix Sepsis criteria and the diagnostic Phoenix 8 Sepsis criteria.

Usage

phoenix_respiratory(
  pf_ratio = NA_real_,
  sf_ratio = NA_real_,
  imv = NA_integer_,
  other_respiratory_support = NA_integer_,
  data = parent.frame(),
  ...
)

Value

a integer vector with values 0, 1, 2, or 3.

As with all other Phoenix organ system scores, missing values in the data set will map to a score of zero - this is consistent with the development of the criteria.

Arguments

pf_ratio

numeric vector for the PaO2/FiO2 ratio; PaO2 = arterial oxygen pressure; FiO2 = fraction of inspired oxygen; PaO2 is measured in mmHg and FiO2 is from 0.21 (room air) to 1.00.

sf_ratio

numeric vector for the SpO2/FiO2 ratio; SpO2 = oxygen saturation, measured in a percent; ratio for 92% oxygen saturation on room air is 92/0.21 = 438.0952.

imv

invasive mechanical ventilation; numeric or integer vector, (0 = not intubated; 1 = intubated)

other_respiratory_support

other respiratory support; numeric or integer vector, (0 = no support; 1 = support)

data

a list, data.frame, or environment containing the input vectors

...

pass through

Phoenix Respiratory Scoring

0 points	1 point	2 points	3 points
pf_ratio >= 400 and sf_ratio >= 292	(pf_ratio < 400 or sf_ratio < 292) and any respiratory support	(pf_ratio < 200 or sf_ratio < 220) and imv	(pf_ratio < 100 or sf_ratio < 148) and imv

Details

pf_ratio is the ratio of partial pressure of oxygen in arterial blood (PaO2) to the fraction of inspiratory oxygen concentration (FiO2).

sf_ratio is a non-invasive surrogate for pf_ratio using pulse oximetry (SpO2) instead of invasive PaO2.

Important Note: when the Phoenix Sepsis criteria was developed there is a requirement that SpO2 <= 97 in order for the sf_ratio to be valid. That assumption is not checked in this code and it is left to the end user to account for this when building the sf_ratio vector.

imv Invasive mechanical ventilation - integer vector where 0 = not intubated and 1 = intubated.

other_respiratory_support other respiratory support such as receiving oxygen, high-flow, non-invasive positive pressure, or imv.

References

See reference details in phoenix-package or by calling citation('phoenix').

See Also

• phoenix for generating the diagnostic Phoenix Sepsis score based on the four organ systems:

  • phoenix_cardiovascular,

  • phoenix_coagulation,

  • phoenix_neurologic,

  • phoenix_respiratory,

• phoenix8 for generating the diagnostic Phoenix 8 Sepsis criteria based on the four organ systems noted above and

  • phoenix_endocrine,

  • phoenix_immunologic,

  • phoenix_renal,

  • phoenix_hepatic,

vignette('phoenix') for more details and examples.

Examples

# Using the provided example data set:
# Expected units:
#   pf_ratio: PaO2 / FiO2
#     PaO2: mmHg
#     FiO2: decimal between 0.21 (room air) to 1.00 (pure oxygen)
#   sf_ratio: SpO2 / FiO2
#     SpO2: percentage, 0 to 100
#     FiO2: decimal between 0.21 (room air) to 1.00 (pure oxygen)
#   imv: (invasive mechanical ventilation) 1 for yes, 0 for no
#   other_respiratory_support: 1 for yes, 0 for no

phoenix_respiratory(
  pf_ratio = pao2 / fio2,
  sf_ratio = spo2 / fio2,
  imv      = vent,
  other_respiratory_support = as.integer(fio2 > 0.21),
  data = sepsis
)

# A set of values that will get all possible respiratory scores:
DF <- expand.grid(
  pfr = c(NA, 500, 400, 350, 200, 187, 100, 56),
  sfr = c(NA, 300, 292, 254, 220, 177, 148, 76),
  vent = c(NA, 0, 1),
  o2  = c(NA, 0, 1)
)

phoenix_respiratory(
  pf_ratio = pfr,
  sf_ratio = sfr,
  imv = vent,
  other_respiratory_support = o2,
  data = DF
)