Skip to main content

Haemoglobin concentration and mass as determinants of exercise performance and of surgical outcome

Abstract

The ability of the cardiorespiratory system (heart, lungs, blood) to deliver oxygento exercising skeletal muscle constrains maximum oxygen consumption V ˙ O 2 max ,with cardiac output and the concentration of oxygen-carrying haemoglobin ([Hb]) beingkey limiting parameters. Total blood volume (BV) is the sum of the plasma volume (PV)and the total red cell volume. The measured [Hb] is dependent upon the totalcirculating mass of haemoglobin (tHb-mass) and plasma volume (PV). While theproportion of oxygen carried in plasma is trivial (0.3 mL of oxygen per100 mL of plasma), each gram of Hb, contained in red blood cells, binds1.39 mL of oxygen. As a result, the relationship between V ˙ O 2 max and tHb-mass is stronger than that observed between V ˙ O 2 max and [Hb] or BV. The glycoprotein hormone erythropoietin drives red cell synthesisand, like simple transfusion of packed red blood cells, can increase tHb-mass. Aniron-containing haem group lies at the centre of the Hb molecule and, in situationsof actual or functional iron deficiency, tHb-mass will also rise following ironadministration. However achieved, an increase in tHb-mass also increases circulatingoxygen-carrying capacity, and thus the capacity for aerobic phosphorylation. It isfor such reasons that alterations in V ˙ O 2 max and exercise performance are proportional to those in arterial oxygen content andsystemic oxygen transport, a change in tHb-mass of 1 g being associated with a4 mL · min−1 change in V ˙ O 2 max .Similarly, V ˙ O 2 max increases by approximately 1% for each3 g · L−1 increase in [Hb] over the [Hb]range (120 to 170 g · L−1). Surgery, likeexercise, places substantial metabolic demands on the patient. Whilst subject todebate, oxygen supply at a rate inadequate to prevent muscle anaerobiosis mayunderpin the occurrence of the anaerobic threshold (AT), an important submaximalmarker of cardiorespiratory fitness. Preoperatively, cardiopulmonary exercise testing(CPET) can be used to determine AT and peak exertional oxygen uptake( V ˙ O 2 peak) asmeasures of ability to meet increasing oxygen demands. The degree of surgical insultand the ability to meet the resulting additional postoperative oxygen demand appearto be fundamental determinants of surgical outcome: individuals in whom such abilityis impaired (and thus those with reduced V ˙ O 2 peakand AT) are at greater risk of adverse surgical outcome. This review provides anoverview of the relationships between [Hb], tHb-mass, exercise capacity, and surgicaloutcome and discusses the potential value of assessing tHb-mass over [Hb].

Review

Introduction

Oxygen (O2) must be transported effectively from the atmosphere to thetissues in order to maintain essential metabolic pathways [1]. The heart, vasculature, and blood function to deliver asufficient supply of O2, as well as metabolic substrate, to the tissues toallow effective resynthesis of adenosine triphosphate (ATP) via the electrontransport chain (ETC.) [2]. Importantly,O2 is the final step in this process acting as the final electronacceptor in the ETC. [3]. Without adequateO2 transfer from the blood to the mitochondria, energy-generatingmechanisms within the mitochondria would come to a halt [4]. At sites with insufficient O2 flow, anaerobicglycolytic metabolism complements ongoing aerobic ATP production, leading to agreater amount of lactic acid [4].

It is generally accepted that the physiological limits of the Fick equation determinethe maximal rate at which O2 can be transported from the environment tothe mitochondria and utilised to support oxidative phosphorylation, termed themaximal oxygen uptake V ˙ O 2 max [5]. This is highlighted in endurance-trained athletes,where O2 transport is the most important limiting factor of V ˙ O 2 max ,while mitochondrial O2 consumption also limits V ˙ O 2 max in untrained individuals [6]. V ˙ O 2 max is attained by the simultaneous increase in Q ˙ (SV × HR) and CaO2-CvO2, where Q ˙ is thecardiac output (determined by the stroke volume (SV) and the heart rate (HR)) andCaO2-CvO2 is the arteriovenous oxygen content difference.The ability to increase CaO2-CvO2 depends primarily on thearterial O2 content and haemoglobin concentration [Hb] [4].

Haemoglobin is an iron-containing globular protein pigment molecule carried withinred blood cells (RBCs) [7]. Haemoglobincarries almost all of the O2 in the blood, with a trivial amount dissolvedin plasma (0.3 mL O2 per 100 mL of plasma) [8]. When fully saturated, assuming a normal [Hb] (e.g.14 g · dL−1 in men) and a constant oxygencapacity of haemoglobin (1.39 mL · g−1),haemoglobin carries nearly 20 mL of O2 per 100 mL of whole blood[7].

Total haemoglobin mass (tHb-mass) represents the absolute mass of circulatinghaemoglobin in the body, and can now be quickly, safely, cheaply, and reliablymeasured using the optimised carbon monoxide (CO) re-breathing method refined bySchmidt and Prommer [9]. Total blood volume(BV) is the sum of plasma volume (PV) and total red cell volume. The measured [Hb] isdependent upon the total circulating mass of haemoglobin (tHb-mass) and plasma volume(PV). However, the proportion of oxygen carried in plasma is trivial, whilst eachgram of Hb binds 1.39 mL of oxygen. Thus, tHb-mass largely determines bloodO2-carrying capacity. In addition, however, tHb-mass can increase BVvia its impact on erythrocyte volume [10]. Ahigh BV is essential for achieving a high Q ˙ as observed in enduranceathletes [11, 12]. Thus,tHb-mass may be a more sensitive marker of blood O2 carrying capacity thanusing [Hb], and has additional influences (e.g. via impacts on BV) on physicalperformance than [Hb].

This review provides an overview of the relationships between [Hb], tHb-mass,exercise capacity, and surgical outcome, and discusses the potential value ofassessing tHb-mass over [Hb].

Manipulation of haemoglobin concentration and physical performance

The link between the O2-carrying capacity of the blood and indices ofexercise capacity such as V Ë™ O 2 max has a long history. This section will focus on the effects of elevating and reducing[Hb] on markers of cardiorespiratory fitness.

Elevation of haemoglobin concentration and maximal oxygen consumption

V ˙ O 2 max rises when systemic [Hb] is increased by RBC infusion [13–21](Figure 1). V ˙ O 2 max and/or exercise endurance have also been shown to increase in circumstances where[Hb] has been elevated by the administration of recombinant human erythropoietin(rhEPO) to healthy individuals [22, 23], athletes [23, 24], haemodialysis patients [25, 26], and patients withheart failure [27, 28], or through the increased Hb synthesis followingadministration of iron supplements [29].Studies that have failed to find such a relationship between [Hb] and exercisecapacity [30] may in part be explained by(i) a small quantity of blood being reinfused, (ii) insufficient time for the bodyto adapt its normal [Hb] post venesection, and (iii) inadequate storage of theRBCs [31]. When these factors areappropriately controlled for, elevating [Hb] is shown to increase V ˙ O 2 max and endurance performance [13]. Gledhilland colleagues [31, 32] have postulated that V ˙ O 2 max increases by approximately 1% for each3 g · L−1 [Hb] over the [Hb] range (120to 170 g · L−1).

Figure 1
figure 1

Relationship between the percent change in [Hb] and percent changein V ˙ O 2 max .Each data point represents the mean of each study using data obtained duringthe first 48 h after [Hb] manipulation. Figure reproduced withpermission from [33] using data fromnine studies [14–18, 34–37].

Reduction of haemoglobin concentration and maximal oxygen consumption

Early work by Ekblom and colleagues [14]demonstrated, in four participants, that a 13% reduction in [Hb] (by venesectionof 800 mL of blood) lowered V ˙ O 2 max by 10% (from 4.54 to 4.09 L · min−1) with agreater effect on endurance time observed (reduced by 30% from 5.77 to4.04 min). In the same study, an additional four participants underwentsequential venesection of 400, 800, and 1,200 mL of whole blood (at 4-dayintervals) that resulted in a reduction in [Hb] of 10%, 15%, and 18%,respectively. These reductions were mirrored by a stepwise impairment in V ˙ O 2 max (6%, 10%, and 16% reduction) and endurance times (13%, 21%, and 30%reduction).

Similar findings have been shown by a number of different authors including Balkeet al. (9% decrease in V ˙ O 2 max 1 h after a 500-mL venesection) [34],Woodson and colleagues (16% decline in V ˙ O 2 max after 34% reduction of [Hb]) [35],Kanstrup and Ekblom (9% reduction in V ˙ O 2 max and 40% lower endurance time at the intensity eliciting V ˙ O 2 max after reducing [Hb] by 11% through the removal of 900 mL blood)[36] and to a lesser extent byRowell et al. (4% decrease in V ˙ O 2 max following a 14% decrease in circulating [Hb] after repeated phlebotomies totaling700–1,000 mL over 5 days) [37].

Change in haemoglobin concentration and anaerobic threshold

Compared to V Ë™ O 2 peak or V Ë™ O 2 max ,less is known about the impact of changes in [Hb] on submaximal markers ofcardiorespiratory fitness such as the AT. The AT represents the highest V Ë™ O 2 (or running speed, power output) that can be performed without developing asustained lactic acidosis [38].

Fritsch and colleagues [39] reported CPETin 16 young healthy participants before and 2 days after a 450-mL venesectionthat resulted in [Hb] being reduced from 14.5 to13.0 g · dL−1 (not classified as anaemicif using the World Health Organisation recommendations [40]). The AT was reduced following venesection whenexpressed as a percentage of V ˙ O 2 max (pre 68.5% versus post 52%) and as an absolute V ˙ O 2 . Ourlaboratory [41] has shown an independentassociation between preoperative [Hb] and AT after adjusting V ˙ O 2 values for known confounders (age, sex, testing site, operation category,diabetes, creatinine) and performing allometric scaling to remove the influence ofbody size from V ˙ O 2 values.Causality cannot be conferred from these data, but nonetheless demonstrate thatthose patients wiot be conferred from these data, but nonetheless demonstrate thatthose patients with the lowest [Hb] displayed the lowest V ˙ O 2 valuesand vice versa. Data from Japan [42]suggest that the AT is lower in patients with iron deficiency anaemia than innon-athletic controls (AT 15.9 ± 3.3 versus21.3 ± 1.3 mL · kg−1 · min−1,p < 0.01) and responds to increases in [Hb] followingiron supplementation ([Hb] 9.0 ± 1.8 to12.1 ± 0.8 g · dL−1),AT (20.9 ± 6.3 to25.0 ± 8.0 mL · kg−1 · min−1,p < 0.001).

Relationship between tHb-mass, blood volume, and exercise capacity

The relationship between markers of cardiorespiratory fitness and tHb-mass isstronger than that with BV or [Hb] [43, 44]. A high correlation between tHb-mass and V ˙ O 2 max (r = 0.97) was observed in the early 1950s by Astrand[45], where differences in maximalaerobic capacity between adults and children and between men and women were relatedto differences in total haemoglobin (see Figure 2). Thisinitial investigation laid the foundation for much of the subsequent work in relationto tHb-mass and aerobic capacity.

Figure 2
figure 2

Relationship between total body haemoglobin (between 100 and 900 g)and V ˙ O 2 max in94 individuals aged 7–30 years[45]. Figure reproduced with permission from[46].

Subsequently, undertaking a meta-analytical approach, Schmidt and Prommer[43] pooled data from 611 subjects. V ˙ O 2 max was determined using either an incremental cycle ergometry test or treadmillprotocol, with. values obtained from treadmill exercise adjusted (specificallyreduced) by 7% to account for the greater muscle mass utilised compared to cycling.tHb-mass was measured in all subjects using the CO re-breathing technique. Resultsrevealed a high correlation (r = 0.79) between V ˙ O 2 max and tHb-mass. A similar close dependency between BV and V ˙ O 2 max (r = 0.76) was highlighted, in keeping with early work byConvertino that showed a similar relationship between total BV and V ˙ O 2 max (r = 0.78) [47]. Nosignificant dependency of V ˙ O 2 max on [Hb] (males r = 0.03, females r = 0.12)or Hct (males r = 0.08, females r = 0.11)was observed.

A number of other cross-sectional studies have demonstrated a strong positiveassociation between V ˙ O 2 max and tHb-mass including that by Gore and colleagues [48] who studied a cohort of trained athletes, female rowers (n =17, r = 0.92, p < 0.0001), male rowers (n = 12,r = 0.79, p < 0.005) and male runners(n = 33, r = 0.48,p = 0.005). Likewise, Heinicke et al. [49] investigated BV and tHb-mass in elite athletes ofdifferent disciplines (downhill skiing, swimming, running, triathlon, cycling junior,and cycling professional), finding that V ˙ O 2 max was significantly related to tHb-mass not only in the whole group but also in allendurance disciplines.

Changes in tHb-mass and exercise capacity

Procedures to increase tHb-mass result in elevated V Ë™ O 2 max ,whereas the opposite is true when tHb-mass is reduced [36], highlighting the importance of tHb-mass as a primarydeterminant of V Ë™ O 2 max by determining O2-carrying capacity.

Elevation of tHb-mass and exercise capacity

When tHb-mass is increased through the use of rhEPO, concomitant increases in V ˙ O 2 max have been reported. Specifically, V ˙ O 2 max increased by 6%–7% in 27 recreational athletes after an increase in tHb-massof 7%–12% and both fitness and blood parameters returned to baseline aftercessation of rhEPO [50]. Similarly, arecent study in 19 trained men showed an improved 3,000-m running time trialperformance (11:08 ± 1:15 to10:30 ± 1:07 min/sec, p < 0.001)following 4 weeks of rhEPO administration. This improved performancecoincided with a rhEPO-induced increase in V ˙ O 2 max (56.0 ± 6.2 to60.7 ± 5.8 mL · kg−1 · min−1,p < 0.001) and tHb-mass (12.7 ± 1.2 to15.2 ± 1.5 g · kg−1,p < 0.001).

What change in aerobic capacity can we expect for a given change in tHb-mass?Linear regression analysis revealed a change in tHb-mass of1 g · kg−1 was associated with a changein V ˙ O 2 max of4.4 mL · kg−1 · min−1(males4.2 mL · kg−1 · min−1,females4.6 mL · kg−1 · min−1)and a change in BV of 1 mL blood per kilogram was related to a change in V ˙ O 2 max of0.7 mL · kg−1 · min−1[43]. In 144 male athletes of various specialitieswith absolute V ˙ O 2 max values ranging from 1,010 to6,320 mL · min−1 and tHb-mass from 242to 1,453 g, a change in 1 g of haemoglobin was associated with a changein V ˙ O 2 max by around 4 mL · min−1[51]. This is the same as reported by Gore andcolleagues [48] and very similar to thatrecently reported in an excellent review article in this area [10]. Understanding what change in aerobic capacitywe can expect from a change in tHb-mass is important because it allows an accurateprediction of likely improvements in functional capacity as a result of anintervention to improve tHb-mass.

Reduction of tHb-mass and exercise capacity

After 550 mL of whole blood had been withdrawn from 9 moderately trained maleand female athletes, tHb-mass was reduced on average by77 ± 21 g [52]. Thiswas significantly associated with a decline in V ˙ O 2 max of 255 ± 130 mL · min−1(1 day post phlebotomy) and was still decreased on day 10(197 ± 116 mL · min−1).The authors commented on a suppression of endurance performance during this periodof lower tHb-mass. tHb-mass has also been shown to be reduced(868 ± 99 to 840 ± 94 g,p = 0.03) following a 30-day detraining period (87% reductionin training hours) with a reciprocal decrease in V ˙ O 2 max (4.83 ± 0.29 to4.61 ± 0.41 L · min−1)observed [53]. Given these findings andthat tHb-mass is lower in healthy sedentary individuals than in those who areathletically trained [54], would sickpatients have a lower tHb-mass by virtue of inactivity? And might the relationshipbetween lower aerobic capacity and poorer operative outcome be in part mediatedthrough a sedentary lifestyle-associated reduction in tHb-mass?

Mechanisms for reduced exercise capacity following haematological changes

A reduction in [Hb] due to a fall in tHb-mass may impair exercise capacity in anumber of ways. Firstly, a reduction in CaO2 will reduce muscleO2 availability (O2 delivery) for the same muscle blood flow[55]. Secondly, muscleO2-diffusing capacity is lower when [Hb] is reduced, which may be relatedto alterations in the intracapillary spacing of erythrocytes or slower dissociationof O2 from [Hb] [56]. Thirdly,pulmonary diffusion is reduced when [Hb] is reduced. Finally, a reduction incirculating BV may also impact aerobic capacity by affecting ventricular preload(diastolic function) via the Frank-Starling mechanism, thus altering SV and Q Ë™ [11, 57]. However, it appears that thepredominant mechanism explaining the detrimental impact of reduced [Hb] on V Ë™ O 2 max and (to a greater extent) exercise endurance is the lowered O2-carryingcapacity of the blood [33], with [Hb] beingmore important to V Ë™ O 2 max in the untrained than in trained individuals [6]. This may have significant implications in patientpopulations.

Similar mechanisms may underpin the reduced AT observed when [Hb] is reduced but thisis a much-debated and controversial concept [58, 59]. The AT represents the highest V Ë™ O 2 (orrunning speed, power output) that can be performed without developing a sustainedlactic acidosis [38]. When performingexercise above the AT, it is suggested that the metabolic demands of tissues(mitochondria) outstrips O2 supply, and aerobic ATP resynthesis issupplemented by anaerobic metabolism leading to increased lactate production relativeto the rate of glycolysis (i.e. increased lactate/pyruvate ratio) [60]. The AT is therefore an important marker ofcardiorespiratory fitness as it provides an assessment of the ability of thecardiovascular system to supply O2 at a rate adequate to prevent muscleanaerobiosis [38]. A reduced capacity tosupply O2 to actively respiring tissues caused by low [Hb] orcardiovascular disease conditions has the potential to reduce the AT.

Surgical outcome, tHb-mass, and cardiorespiratory fitness

The measurement of tHb-mass (rather than [Hb]) in the clinical setting may haveimportant applications but these remain relatively unexplored. For example, [Hb] mayvary as intravascular fluid shifts as a result of disease states or their treatment,making it a poor index of oxygen-carrying capacity. [Hb] is determined by tHb-massand the total volume of blood. A substantial reduction in oxygen-carrying capacity,related to a low tHb-mass, may thus be masked if PV is contracted, as may be the casein many disease states. Similarly, increases in intravascular volume may depress[Hb], even in the context of a normal tHb-mass. Knowledge of tHb-mass and [Hb] allowscalculation of PV as a separate variable, allowing evaluation of disease-relatedfluid shifts. The degree of surgical blood loss might also be better quantifiedthrough the measurement of tHb-mass than [Hb]. More importantly, perhaps, tHb-massmay represent a more sensitive marker of blood O2 transport capacity than[Hb] in isolation [61].

Major surgery can be defined as any intervention occurring in a hospital operatingtheatre involving the incision, excision, manipulation, or suturing of tissue,usually requiring regional or general anaesthesia or sedation [62]. The determinants of surgical outcome (morbidityand mortality) are related to an interplay between the health and fitness ofpatients, the number and severity of comorbidities present [63], and patient age as well as surgery-related factors(emergency or planned, mode, type, and duration). In addition, the systemicinflammatory response caused by hormonal, immunological, and metabolic mediators[64] is essential for effective tissuerepair and healing after surgery. Effective O2 delivery to the tissuesduring the hypermetabolic postoperative period is thought to be a fundamentaldeterminant of surgical outcome [65, 66] with patients who are unable to raise O2delivery to meet the increased V Ë™ O 2 requirementmore frequently developing complications [67, 68]. The cause of this uncoupling of O2supply and demand is multifactorial but may be predominantly linked to theinteraction between a patient's existing comorbidities (e.g. cardiac disease,respiratory disease, or indeed any condition that impairs O2 deliveryand/or cardiac output) and the degree of surgical insult [69].

Impairment in the ability to meet these demands can be determined preoperativelythrough the assessment of exertional V ˙ O 2 peak and AT(by CPET); reductions in both markers of functional capacity are associated with anincreased risk of perioperative morbidity and mortality [70–74]. The original work by Older andcolleagues almost 2 decades ago was the first to highlight the association betweenlow functional capacity by CPET and adverse patient outcome followingnon-cardiopulmonary surgery [75].Specifically, a reduced cardiorespiratory reserve, typically defined as an AT of lessthan11 mL · kg−1 · min−1being associated with an increased risk of adverse postoperative outcome followingmajor intra-cavity surgery [74]. Similarly,impaired V ˙ O 2 peakhas been shown to predict worse postoperative outcome following major lung resection( V ˙ O 2 peak<20 mL · kg−1 · min−1[76],<15 mL · kg−1 · min−1[77]) and bariatric surgery ( V ˙ O 2 peak<16 mL · kg−1 · min−1)[78]. The reader is referred to anexcellent systematic review in this area covering the role of CPET as a preoperativerisk stratification tool in non-cardiopulmonary surgery for more details[74].

It is acknowledged that although the V ˙ O 2 response froman exercise test is not directly comparable to that in a postoperative patient,common with exercise, V ˙ O 2 postoperatively in major surgery is high [79]. For example, preoperative resting V ˙ O 2 has been shownto increase from 110 to approximately170 mL · min−1 · m−2[80, 81] indicating a greaterrequirement for O2 following surgery. In this context, tHb-mass may beimportant to surgical outcome due to its role in determining O2 delivery.This may be related to the close linear relationship that exists between tHb-mass,BV, Q ˙ , andaerobic capacity [10]. For example, a high BVis a prerequisite for a high tHb-mass, which in turn impacts upon Q ˙ byelevating venous return and cardiac filling pressures [82, 83]. Because tHb-mass in combinationwith BV also governs [Hb] and therefore oxygen-carrying capacity, the effects oftHb-mass on determining O2 delivery are twofold. Given the closerelationship between tHb-mass and aerobic capacity and the association betweenmarkers of cardiorespiratory fitness ( V ˙ O 2 peak and AT)and surgical outcome, it would seem intuitive that a high tHb-mass may confer asurvival advantage in the perioperative setting. If this is the case, then strategiesaimed at elevating tHb-mass may improve outcome (morbidity and mortality) followingsurgery, but this remains to be confirmed. Given that anaemia is associated with anincreased risk of adverse surgical outcome, it would be surprising if thisrelationship were not maintained for tHb-mass.

Conclusion

Changes in [Hb] and tHb-mass are associated with reciprocal alterations in exercisecapacity proportional to the change in oxygen-carrying capacity of the blood. tHb-massdisplays a stronger relationship with V Ë™ O 2 max than [Hb] or BV. In the context of surgery, patients with an inability to raise oxygendelivery to meet the increased V Ë™ O 2 requirement ofthe perioperative period will more frequently develop complications. Impairment in theability to meet these demands can be determined preoperatively through the assessment ofexertional V Ë™ O 2 peak andAT (by CPET), reductions in both markers being associated with an increased risk adversesurgical outcome. Whether differences in tHb-mass are associated with postoperativeoutcome is not known but an interesting question given the high prevalence ofpreoperative anaemia itself being associated with an increased risk of poor outcome. Inaddition, the extent to which postoperative outcomes are dependent upon interactionsbetween [Hb], tHb-mass, and V Ë™ O 2 is unknown andwhether strategies to increase tHb-mass result in improved surgical outcome remains tobe clarified.

Abbreviations

AT:

anaerobic threshold

CaO2-CvO2:

arteriovenous oxygen content difference

BV:

bloodvolume

CO:

carbon monoxide

CPET:

cardiopulmonary exercise testing

rhEPO:

recombinanthuman erythropoietin

ESA:

erythropoietin-stimulating agent

EV:

erythrocyte volume

DO2:

oxygen delivery

Hct:

haematocrit

Hb:

haemoglobin concentration

O2:

oxygen

PA:

physical activity

PV:

plasma volume

tHb-mass:

total haemoglobin mass

V Ë™ O 2 :

oxygen consumption;

V Ë™ O 2 max :

maximal oxygen consumption;

V Ë™ O 2 :

peak oxygen consumption;

CaO2:

arterial oxygen content

Q Ë™ :

cardiac output.

References

  1. Vincent JL, De Backer D: Oxygen transport-the oxygen delivery controversy. Intensive Care Med. 2004, 30 (11): 1990-1996. 10.1007/s00134-004-2384-4.

    Article  PubMed  Google Scholar 

  2. Nathan AT, Singer M: The oxygen trail: tissue oxygenation. Br Med Bull. 1999, 55 (1): 96-108. 10.1258/0007142991902312.

    Article  CAS  PubMed  Google Scholar 

  3. Williams C: Haemoglobin–is more better?. Nephrol Dial Transplant. 1995, 10 (Suppl 2): 48-55.

    Article  PubMed  Google Scholar 

  4. Wasserman K, Hansen JE, Sue DY, Stringer WW, Whipp BJ: Principles of Exercise Testing and Interpretation Including Pathophysiology andClinical Applications. 2005, Philadelphia: Lippincott Williams & Wilkins,

    Google Scholar 

  5. Levine BD: VO2max: what do we know, and what do we still need to know?. J Physiol. 2008, 586 (1): 25-34.

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  6. Wagner PD: New ideas on limitations to VO2max. Exerc Sport Sci Rev. 2000, 28 (1): 10-14.

    CAS  PubMed  Google Scholar 

  7. McArdle DW, Katch FI, Katch VL: Gas exchange and transport. Exercise Physiology: Energy, Nutrition and Human Performance. 2001, Philadelphia, Pennsylvania: Lippincott Williams & Wilkins: DarcyP, 270-284.

    Google Scholar 

  8. Pittman RN: Regulation of Tissue Oxygenation. 2011, Morgan & Claypool Life Sciences: San Rafael, CA

    Google Scholar 

  9. Schmidt W, Prommer N: The optimised CO-rebreathing method: a new tool to determine total haemoglobinmass routinely. Eur J Appl Physiol. 2005, 95 (5–6): 486-495.

    Article  CAS  PubMed  Google Scholar 

  10. Schmidt W, Prommer N: Impact of alterations in total hemoglobin mass on VO2max. Exerc Sport Sci Rev. 2010, 38 (2): 68-75. 10.1097/JES.0b013e3181d4957a.

    Article  PubMed  Google Scholar 

  11. Krip B, Gledhill N, Jamnik V, Warburton D: Effect of alterations in blood volume on cardiac function during maximalexercise. Med Sci Sports Exerc. 1997, 29 (11): 1469-1476. 10.1097/00005768-199711000-00013.

    Article  CAS  PubMed  Google Scholar 

  12. Ekblom B, Hermansen L: Cardiac output in athletes. J Appl Physiol. 1968, 25 (5): 619-625.

    CAS  PubMed  Google Scholar 

  13. Sawka MN, Young AJ: Acute polycythemia and human performance during exercise and exposure to extremeenvironments. Exerc Sport Sci Rev. 1989, 17: 265-293.

    CAS  PubMed  Google Scholar 

  14. Ekblom B, Goldbarg AN, Gullbrin B: Response to exercise after blood loss and reinfusion. J Appl Physiol. 1972, 33 (2): 175-180.

    CAS  PubMed  Google Scholar 

  15. Ekblom B, Wilson G, Astrand PO: Central circulation during exercise after venesection and reinfusion of red bloodcells. J Appl Physiol. 1976, 40 (3): 379-383.

    CAS  PubMed  Google Scholar 

  16. Buick FJ, Gledhill N, Froese AB, Spriet L, Meyers EC: Effects of induced erythrocythemia on aerobic work capacity. J Appl Physiol. 1980, 48 (4): 636-642.

    CAS  PubMed  Google Scholar 

  17. Turner DL, Hoppeler H, Noti C, Gurtner HP, Gerber H, Schena F, Kayser B, Ferretti G: Limitations to VO2max in humans after blood retransfusion. Respir Physiol. 1993, 92 (3): 329-341. 10.1016/0034-5687(93)90017-5.

    Article  CAS  PubMed  Google Scholar 

  18. Spriet LL, Gledhill N, Froese AB, Wilkes DL: Effect of graded erythrocythemia on cardiovascular and metabolic responses toexercise. J Appl Physiol. 1986, 61 (5): 1942-1948.

    CAS  PubMed  Google Scholar 

  19. Williams MH, Wesseldine S, Somma T, Schuster R: The effect of induced erythrocythemia upon 5-mile treadmill run time. Med Sci Sports Exerc. 1981, 13 (3): 169-175.

    Article  CAS  PubMed  Google Scholar 

  20. Brien AJ, Simon TL: The effects of red blood cell infusion on 10-km race time. JAMA. 1987, 257 (20): 2761-2765. 10.1001/jama.1987.03390200101022.

    Article  CAS  PubMed  Google Scholar 

  21. Celsing F, Svedenhag J, Pihlstedt P, Ekblom B: Effects of anaemia and stepwise-induced polycythaemia on maximal aerobic power inindividuals with high and low haemoglobin concentrations. Acta Physiol Scand. 1987, 129 (1): 47-54. 10.1111/j.1748-1716.1987.tb08038.x.

    Article  CAS  PubMed  Google Scholar 

  22. Ekblom B, Berglund B: Effect of erythropoietin administration on maximal aerobic power. Scand J Med Sci Sports. 1991, 1: 88-93.

    Article  Google Scholar 

  23. Thomsen JJ, Rentsch RL, Robach P, Calbet JA, Boushel R, Rasmussen P, Juel C, Lundby C: Prolonged administration of recombinant human erythropoietin increases submaximalperformance more than maximal aerobic capacity. Eur J Appl Physiol. 2007, 101 (4): 481-486. 10.1007/s00421-007-0522-8.

    Article  CAS  PubMed  Google Scholar 

  24. Ekblom BT: Blood boosting and sport. Baillieres Best Pract Res Clin Endocrinol Metab. 2000, 14 (1): 89-98. 10.1053/beem.2000.0056.

    Article  CAS  PubMed  Google Scholar 

  25. Barany P, Freyschuss U, Pettersson E, Bergstrom J: Treatment of anaemia in haemodialysis patients with erythropoietin: long-termeffects on exercise capacity. Clin Sci (Lond). 1993, 84 (4): 441-447.

    Article  CAS  Google Scholar 

  26. Robertson HT, Haley NR, Guthrie M, Cardenas D, Eschbach JW, Adamson JW: Recombinant erythropoietin improves exercise capacity in anemic hemodialysispatients. Am J Kidney Dis. 1990, 15 (4): 325-332. 10.1016/S0272-6386(12)80079-5.

    Article  CAS  PubMed  Google Scholar 

  27. Kotecha D, Ngo K, Walters JA, Manzano L, Palazzuoli A, Flather MD: Erythropoietin as a treatment of anemia in heart failure: systematic review ofrandomized trials. Am Heart J. 2011, 161 (5): 822-831. 10.1016/j.ahj.2011.02.013.

    Article  CAS  PubMed  Google Scholar 

  28. Lawler PR, Filion KB, Eisenberg MJ: Correcting anemia in heart failure: the efficacy and safety oferythropoiesis-stimulating agents. J Card Fail. 2010, 16 (8): 649-658. 10.1016/j.cardfail.2010.03.013.

    Article  CAS  PubMed  Google Scholar 

  29. Magazanik A, Weinstein Y, Abarbanel J, Lewinski U, Shapiro Y, Inbar O, Epstein S: Effect of an iron supplement on body iron status and aerobic capacity of youngtraining women. Eur J Appl Physiol Occup Physiol. 1991, 62 (5): 317-323. 10.1007/BF00634966.

    Article  CAS  PubMed  Google Scholar 

  30. Robinson BF, Epstein SE, Kahler RL, Braunwal E: Circulatory effects of acute expansion of blood volume - studies during maximalexercise and at rest. Circ Res. 1966, 19 (1): 26-32. 10.1161/01.RES.19.1.26.

    Article  Google Scholar 

  31. Gledhill N: Blood doping and related issues: a brief review. Med Sci Sports Exerc. 1982, 14 (3): 183-189.

    Article  CAS  PubMed  Google Scholar 

  32. Gledhill N, Warburton D, Jamnik V: Haemoglobin, blood volume, cardiac function, and aerobic power. Can J Appl Physiol. 1999, 24 (1): 54-65. 10.1139/h99-006.

    Article  CAS  PubMed  Google Scholar 

  33. Calbet JA, Lundby C, Koskolou M, Boushel R: Importance of hemoglobin concentration to exercise: acute manipulations. Respir Physiol Neurobiol. 2006, 151 (2–3): 132-140.

    Article  CAS  PubMed  Google Scholar 

  34. Balke B, Grillo GP, Konecci EB, Luft UC: Work capacity after blood donation. J Appl Physiol. 1954, 7 (3): 231-238.

    CAS  PubMed  Google Scholar 

  35. Woodson RD, Wills RE, Lenfant C: Effect of acute and established anemia on O2 transport at rest, submaximal andmaximal work. J Appl Physiol. 1978, 44 (1): 36-43.

    CAS  PubMed  Google Scholar 

  36. Kanstrup IL, Ekblom B: Blood volume and hemoglobin concentration as determinants of maximal aerobicpower. Med Sci Sports Exerc. 1984, 16 (3): 256-262.

    Article  CAS  PubMed  Google Scholar 

  37. Rowell LB, Taylor HL, Yang W: Limitations to prediction of maximal oxygen intake. J Appl Physiol. 1964, 19 (5): 919-927.

    CAS  PubMed  Google Scholar 

  38. Wasserman K, Beaver WL, Whipp BJ: Gas exchange theory and the lactic acidosis (anaerobic) threshold. Circulation. 1990, 81 (1 Suppl): II14-II30.

    CAS  PubMed  Google Scholar 

  39. Fritsch J, Winter UJ, Reupke I, Gitt AK, Berge PG, Hilger HH: Effect of a single blood donation on ergo-spirometrically determinedcardiopulmonary performance capacity of young healthy probands. Z Kardiol. 1993, 82 (7): 425-431.

    CAS  PubMed  Google Scholar 

  40. WHO: Iron Deficiency Anaemia. 2001, Geneva: Assessment, Prevention and Control (A Guide for ProgrammeManagers), 1-114.

    Google Scholar 

  41. Otto JM, O'Doherty AF, Hennis PJ, Cooper JA, Grocott MP, Snowden C, Carlisle JB, Swart M, Richards T, Montgomery HE: Association between preoperative haemoglobin concentration and cardiopulmonaryexercise variables: a multicentre study. Perioperative Med. 2013, 2 (18): 13-

    Google Scholar 

  42. Yonezawa K: Effect of blood hemoglobin concentration on anaerobic threshold. Hokkaido Igaky Zasshi. 1991, 66 (4): 458-467.

    CAS  Google Scholar 

  43. Schmidt W, Prommer N: Effects of various training modalities on blood volume. Scand J Med Sci Sports. 2008, 18 (Suppl 1): 57-69.

    Article  PubMed  Google Scholar 

  44. Sawka MN, Convertino VA, Eichner ER, Schnieder SM, Young AJ: Blood volume: importance and adaptations to exercise training, environmentalstresses, and trauma/sickness. Med Sci Sports Exerc. 2000, 32 (2): 332-348. 10.1097/00005768-200002000-00012.

    Article  CAS  PubMed  Google Scholar 

  45. Astrand PO: Experimental studies of physical working capacity in relation to sex andage. 1952, Copenhagen: Munksgaard,

    Google Scholar 

  46. Joyner MJ: VO2max, blood doping, and erythropoietin. Br J Sports Med. 2003, 37 (3): 190-191.

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  47. Convertino VA: Blood volume: its adaptation to endurance training. Med Sci Sports Exerc. 1991, 23 (12): 1338-1348.

    Article  CAS  PubMed  Google Scholar 

  48. Gore CJ, Hahn AG, Burge CM, Telford RD: VO2max and haemoglobin mass of trained athletes during high intensity training. Int J Sports Med. 1997, 18 (6): 477-482.

    Article  CAS  PubMed  Google Scholar 

  49. Heinicke K, Wolfarth B, Winchenbach P, Biermann B, Schmid A, Huber G, Friedmann B, Schmidt W: Blood volume and hemoglobin mass in elite athletes of different disciplines. Int J Sports Med. 2001, 22 (7): 504-512. 10.1055/s-2001-17613.

    Article  CAS  PubMed  Google Scholar 

  50. Parisotto R, Gore CJ, Emslie KR, Ashenden MJ, Brugnara C, Howe C, Martin DT, Trout GJ, Hahn AG: A novel method utilising markers of altered erythropoiesis for the detection ofrecombinant human erythropoietin abuse in athletes. Haematologica. 2000, 85 (6): 564-572.

    CAS  PubMed  Google Scholar 

  51. Schmidt W, Doerfler C, Wachsmuth N, Voelzke C, Treff G, Thoma S, Steinacker J, Niess A, Prommer N: Influence of body mass, body composition and performance state on total hemoglobinmass. Med Sci Sports Exerc. 2009, 41 (5 Supplement 1): 461-

    Article  Google Scholar 

  52. Prommer N, Heckel A, Schmidt W: Timeframe to detect blood withdrawal associated with autologous blood doping. Med Sci Sports Exerc. 2007, 39: S3-

    Article  Google Scholar 

  53. Eastwood A, Bourdon PC, Snowden KR, Gore CJ: Detraining decreases Hb(mass) of triathletes. Int J Sports Med. 2012, 33 (4): 253-257.

    Article  CAS  PubMed  Google Scholar 

  54. Koponen AS, Peltonen JE, Paivinen MK, Aho JM, Hagglund HJ, Uusitalo AL, Lindholm HJ, Tikkanen HO: Low total haemoglobin mass, blood volume and aerobic capacity in men with type 1diabetes. Eur J Appl Physiol. 2013, 113 (5): 1181-8. 10.1007/s00421-012-2532-4.

    Article  CAS  PubMed  Google Scholar 

  55. Burnley M, Roberts CL, Thatcher R, Doust JH, Jones AM: Influence of blood donation on O2 uptake on-kinetics, peak O2 uptake and time toexhaustion during severe-intensity cycle exercise in humans. Exp Physiol. 2006, 91 (3): 499-509. 10.1113/expphysiol.2005.032805.

    Article  PubMed  Google Scholar 

  56. Schaffartzik W, Barton ED, Poole DC, Tsukimoto K, Hogan MC, Bebout DE, Wagner PD: Effect of reduced hemoglobin concentration on leg oxygen uptake during maximalexercise in humans. J Appl Physiol. 1993, 75 (2): 491-498. Discussion 489–90,

    CAS  PubMed  Google Scholar 

  57. Warburton DE, Gledhill N, Jamnik VK, Krip B, Card N: Induced hypervolemia, cardiac function, VO2max, and performance of elitecyclists. Med Sci Sports Exerc. 1999, 31 (6): 800-808. 10.1097/00005768-199906000-00007.

    Article  CAS  PubMed  Google Scholar 

  58. Hopker JG, Jobson SA, Pandit JJ: Controversies in the physiological basis of the ‘anaerobic threshold’and their implications for clinical cardiopulmonary exercise testing. Anaesthesia. 2011, 66 (2): 111-123. 10.1111/j.1365-2044.2010.06604.x.

    Article  CAS  PubMed  Google Scholar 

  59. Whipp BJ, Ward SA: The physiological basis of the ‘anaerobic threshold’ and implicationsfor clinical cardiopulmonary exercise testing. Anaesthesia. 2011, 66 (11): 1048-1049. 10.1111/j.1365-2044.2011.06909_1.x. author reply 1049–50,

    Article  CAS  PubMed  Google Scholar 

  60. Wasserman K: Determinants and detection of anaerobic threshold and consequences of exerciseabove it. Circulation. 1987, 76 (6 Pt 2): VI29-VI39.

    CAS  PubMed  Google Scholar 

  61. Kjellberg SR, Rudhe U, Sjostrand T: Increase of the amount of hemoglobin and blood volume in connection with physicaltraining. Acta Physiol Scand. 1949, 19 (2-3): 146-151. 10.1111/j.1748-1716.1949.tb00146.x.

    Article  Google Scholar 

  62. Weiser TG, Regenbogen SE, Thompson KD, Haynes AB, Lipsitz SR, Berry WR, Gawande AA: An estimation of the global volume of surgery: a modelling strategy based onavailable data. Lancet. 2008, 372 (9633): 139-144. 10.1016/S0140-6736(08)60878-8.

    Article  PubMed  Google Scholar 

  63. Moonesinghe SR, Mythen MG, Grocott MP: Patient-related risk factors for postoperative adverse events. Curr Opin Crit Care. 2009, 15 (4): 320-327. 10.1097/MCC.0b013e32832e067c.

    Article  PubMed  Google Scholar 

  64. Toft P, Tonnesen E: The systemic inflammatory response to anaesthesia and surgery. Current Anaesthesia Critical Care. 2008, 19 (5): 349-353.

    Article  Google Scholar 

  65. Bland RD, Shoemaker WC: Common physiologic patterns in general surgical patients: hemodynamic and oxygentransport changes during and after operation in patients with and withoutassociated medical problems. Surg Clin North Am. 1985, 65 (4): 793-809.

    CAS  PubMed  Google Scholar 

  66. Shoemaker WC, Appel PL, Waxman K, Schwartz S, Chang P: Clinical trial of survivors' cardiorespiratory patterns as therapeutic goals incritically ill postoperative patients. Crit Care Med. 1982, 10 (6): 398-403. 10.1097/00003246-198206000-00015.

    Article  CAS  PubMed  Google Scholar 

  67. Peerless JR, Alexander JJ, Pinchak AC, Piotrowski JJ, Malangoni MA: Oxygen delivery is an important predictor of outcome in patients with rupturedabdominal aortic aneurysms. Ann Surg. 1998, 227 (5): 726-732. 10.1097/00000658-199805000-00013. Discussion 732–4,

    Article  PubMed Central  CAS  PubMed  Google Scholar 

  68. Kusano C, Baba M, Takao S, Sane S, Shimada M, Shirao K, Natsugoe S, Fukumoto T, Aikou T: Oxygen delivery as a factor in the development of fatal postoperativecomplications after oesophagectomy. Br J Surg. 1997, 84 (2): 252-257. 10.1002/bjs.1800840232.

    Article  CAS  PubMed  Google Scholar 

  69. Fleisher LA, Beckman JA, Brown KA, Calkins H, Chaikof E, Fleischmann KE, Freeman WK, Froehlich JB, Kasper EK, Kersten JR, Riegel B, Robb JF, Smith SC, Jacobs AK, Adams CD, Anderson JL, Antman EM, Buller CE, Creager MA, Ettinger SM, Faxon DP, Fuster V, Halperin JL, Hiratzka LF, Hunt SA, Lytle BW, Nishimura R, Ornato JP, Page RL, Tarkington LG, Yancy CW: ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care fornoncardiac surgery: a report of the American College of Cardiology/American HeartAssociation Task Force on Practice Guidelines (writing Committee to Revise the2002 Guidelines on Perioperative Cardiovascular Evaluation for NoncardiacSurgery): developed in collaboration with the American Society ofEchocardiography, American Society of Nuclear Cardiology, Heart Rhythm Society,Society of Cardiovascular Anesthesiologists, Society for CardiovascularAngiography and Interventions, Society for Vascular Medicine and Biology, andSociety for Vascular Surgery. Circulation. 2007, 116 (17): e418-e499. 10.1161/CIRCULATIONAHA.107.185699.

    Article  PubMed  Google Scholar 

  70. Carlisle J, Swart M: Mid-term survival after abdominal aortic aneurysm surgery predicted bycardiopulmonary exercise testing. Br J Surg. 2007, 94 (8): 966-969. 10.1002/bjs.5734.

    Article  CAS  PubMed  Google Scholar 

  71. Older P, Hall A, Hader R: Cardiopulmonary exercise testing as a screening test for perioperative managementof major surgery in the elderly. Chest. 1999, 116 (2): 355-362. 10.1378/chest.116.2.355.

    Article  CAS  PubMed  Google Scholar 

  72. Snowden CP, Prentis JM, Anderson HL, Roberts DR, Randles D, Renton M, Manas DM: Submaximal cardiopulmonary exercise testing predicts complications and hospitallength of stay in patients undergoing major elective surgery. Ann Surg. 2010, 251 (3): 535-541. 10.1097/SLA.0b013e3181cf811d.

    Article  PubMed  Google Scholar 

  73. Wilson RJ, Davies S, Yates D, Redman J, Stone M: Impaired functional capacity is associated with all-cause mortality after majorelective intra-abdominal surgery. Br J Anaesth. 2010, 105 (3): 297-303. 10.1093/bja/aeq128.

    Article  CAS  PubMed  Google Scholar 

  74. Hennis PJ, Meale PM, Grocott MP: Cardiopulmonary exercise testing for the evaluation of perioperative risk innon-cardiopulmonary surgery. Postgrad Med J. 2011, 87 (1030): 550-557. 10.1136/pgmj.2010.107185.

    Article  PubMed  Google Scholar 

  75. Older P, Smith R, Courtney P, Hone R: Preoperative evaluation of cardiac failure and ischemia in elderly patients bycardiopulmonary exercise testing. Chest. 1993, 104 (3): 701-704. 10.1378/chest.104.3.701.

    Article  CAS  PubMed  Google Scholar 

  76. Brunelli A, Belardinelli R, Refai M, Salati M, Socci L, Pompili C, Sabbatini A: Peak oxygen consumption during cardiopulmonary exercise test improves riskstratification in candidates to major lung resection. Chest. 2009, 135 (5): 1260-1267. 10.1378/chest.08-2059.

    Article  PubMed  Google Scholar 

  77. Bayram AS, Candan T, Gebitekin C: Preoperative maximal exercise oxygen consumption test predicts postoperativepulmonary morbidity following major lung resection. Respirology. 2007, 12 (4): 505-510. 10.1111/j.1440-1843.2007.01097.x.

    Article  PubMed  Google Scholar 

  78. McCullough PA, Gallagher MJ, Dejong AT, Sandberg KR, Trivax JE, Alexander D, Kasturi G, Jafri SM, Krause KR, Chengelis DL, Moy J, Franklin BA: Cardiorespiratory fitness and short-term complications after bariatric surgery. Chest. 2006, 130 (2): 517-525. 10.1378/chest.130.2.517.

    Article  PubMed  Google Scholar 

  79. Older P: Anaerobic threshold, is it a magic number to determine fitness for surgery?. Perioperative Med. 2013, 2: 2-10.1186/2047-0525-2-2.

    Article  Google Scholar 

  80. Older P, Smith R: Experience with the preoperative invasive measurement of haemodynamic, respiratoryand renal function in 100 elderly patients scheduled for major abdominalsurgery. Anaesth Intensive Care. 1988, 16 (4): 389-395.

    CAS  PubMed  Google Scholar 

  81. Shoemaker WC, Appel PL, Kram HB, Waxman K, Lee TS: Prospective trial of supranormal values of survivors as therapeutic goals inhigh-risk surgical patients. Chest. 1988, 94 (6): 1176-1186. 10.1378/chest.94.6.1176.

    Article  CAS  PubMed  Google Scholar 

  82. Young DB: Control of Cardiac Output. 2010, Morgan & Claypool Life Sciences: San Rafael (VA)

    Google Scholar 

  83. Ekblom B: Effect of physical training on oxygen transport system in man. Acta Physiol Scand Suppl. 1968, 328: 1-45.

    CAS  PubMed  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to James M Otto.

Additional information

Competing interests

JMO is receiving an Impact PhD Studentship part-funded by VIFOR (INTERNATIONAL) Inc.with a total funding of £32,534 over 3 years. All remaining authors declarethat they have no competing interests.

Authors’ contributions

JMO, HEM, and TR were responsible for drafting and revising the article. All authorsread and approved the final manuscript.

Authors’ original submitted files for images

Below are the links to the authors’ original submitted files for images.

Authors’ original file for figure 1

Authors’ original file for figure 2

Rights and permissions

Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution 2.0 International License (https://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Reprints and permissions

About this article

Cite this article

Otto, J.M., Montgomery, H.E. & Richards, T. Haemoglobin concentration and mass as determinants of exercise performance and of surgical outcome. Extrem Physiol Med 2, 33 (2013). https://doi.org/10.1186/2046-7648-2-33

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/2046-7648-2-33

Keywords