BSA Calculation for a 5'8" Male Weighing 160 lb
For a 5'8" (173 cm) male weighing 160 lb (72.6 kg), the body surface area is approximately 1.85 m² using standard calculation formulas.
Calculation Method
The most widely recommended formula for BSA calculation is the Gehan and George equation, which is based on the largest study population (401 subjects) and uses least squares estimation 1, 2. This formula provides:
BSA (m²) = 0.0235 × (height in cm)^0.42246 × (weight in kg)^0.51456 1
For your specific measurements:
- Height: 5'8" = 173 cm
- Weight: 160 lb = 72.6 kg
- Calculated BSA ≈ 1.85 m²
Alternative Formulas and Validation
While multiple BSA formulas exist, they show excellent correlation (r > 0.97) across different body habitus 3. The commonly used Mosteller formula provides a simpler calculation that can be done on a pocket calculator: BSA = √[(weight in kg × height in cm)/3600] 3. This would yield approximately 1.84 m² for your measurements, demonstrating the consistency between validated formulas.
The traditional DuBois formula, though historically popular, was derived from only 9 subjects and tends to underestimate BSA in overweight and obese individuals by 3-5% 3, 2.
Clinical Context
BSA is most commonly used when normalized to 1.73 m² for clinical decision-making, particularly for:
- Indexing cardiac chamber dimensions and aortic diameters 4
- Adjusting glomerular filtration rate (eGFR) for renal function assessment 4
- Dosing chemotherapeutic agents with narrow therapeutic windows 1
For drug dosing considerations, particularly in the United States where overweight and obesity are common, individual BSA adjustment (eGFR_BSAadj = eGFR × patient's BSA/1.73 m²) should be utilized rather than the standardized value 4.
Important Caveats
- BSA calculations assume normal body composition and may require adjustment in special populations including amputees and severely malnourished patients 1
- For individuals at extremes of body weight, non-indexed BSA values may be more appropriate for medications with narrow therapeutic ranges 4
- The 1.85 m² BSA for this individual falls within the normal adult range (typically 1.6-2.2 m² for adults) 3