Fentanyl Concentrations (ng/mL)
  CB PB C/P Ratio
N 18 18 18
Min 0.8 0.5 0.49
Max 84 73 1.60
Mean 9.60 10.10 0.95
Median 4.6 5.9 0.94
    Standard Deviation 0.26
CB = Central Blood, PB = Peripheral Blood, C/P = Central/Peripheral Blood
Table 5: Summary of 18 fentanyl cases from the San Diego Medical Examiner’s Office (C/P ratios).