INVITED COMMENTARY

Bellwethers versus Baskets: Operative Capacity and the Metrics

of Global Surgery

Thomas G. Weiser

1,2

Ó Socie

Internationale de Chirurgie 2020

A core concept promoted by health services researchers

interested in the impact of surgical and anesthesia care on

global health programs is that of ‘‘bellwether’’ procedures:

that is, a select set of well-deﬁned operations that repre-

sents the capacity of a facility or health ecosystem to

provide surgical care. The Lancet Commission on Global

Surgery (LCoGS) developed and proposed this concept by

using three conditions—the acute abdomen, obstetric

complications, and open fracture—that, if appropriately

treated, collectively represented the capacity of a facility to

deliver over 90% of emergency and essential surgical care

[1, 2]. Treatment of these conditions became known as

‘‘Bellwether procedures’’, deﬁned as cesarean delivery,

laparotomy, and treatment of open fracture, and were

proposed as archetype operations to evaluate surgical

delivery and the capacity of a health system to deliver

complex but critically essential operative care.

The limitations of the Bellwethers as articulated by the

LCoGS are immediately apparent. Laparotomy is too

generic to interpret, impossible to compare across countries

and settings, and does not provide enough detail of what

was done, what the possible indication might have been, or

how complex the operations actually was. Treatment of

open fracture, while clear in its indication, is not an oper-

ation as it does not provide any indication of the procedure

performed. Only c-section is narrow enough in its

description, delivery and relatively ﬁnite list of indications

to be useful.

Because of these limitations, there has been an argument

made to identify a set of operations that are clearly deﬁned,

are performed for a relatively narrow set of indications,

and treat disease categories amenable to surgical inter-

vention: trauma, emergency obstetric conditions, solid

organ cancers, congenital malformations, certain types of

infections (e.g., appendicitis), and certain diseases of aging

(e.g., coronary artery disease, osteoarthritis of the knee). In

fact, a Delphi process has recently concluded and will

report on the concept of a ‘‘basket’’ of proposed operations

predictably targeted toward speciﬁc diseases that affect

large numbers of patients and whose successful execution

typically results in substantial clinical beneﬁt.

The concept of a basket of operations is akin to the use

of a ‘‘shopping basket’’ of goods and services that reﬂect

spending habits and patterns of consumers as a means of

calculating the Consumer Price Index. ‘‘Goods’’ can be

added or removed over time as habits change, but repre-

sentative goods and services are kept fairly constant.

Instead of the Bellwether procedures, a basket of proce-

dures can be simultaneously more expansive and more

discrete, and represent treatment capacity for a host of

global disease entities such as cancers, injuries, infections,

congenital anomalies, and emergency maternal conditions.

In this issue of the Journal, Truche and colleagues report

on the postoperative mortality rate, or POMR, of the

emergency Bellwether procedures in Brazil, and whether

using a smaller sampling of operations can inform our

understanding of postoperative mortality throughout the

country [3]. They used a national database called DATA-

SUS, representing 60–70% of hospital admissions to esti-

mate POMR for all procedures captured by this system as

well as POMR for emergency laparotomy, open fracture

& Thomas G. Weiser

[email protected]

Section of Trauma and Critical Care, Division of General

Surgery, Department of Surgery, School of Medicine,

Stanford University, 300 Pasteur Drive, H3638, Stanford,

CA 94305, USA

Department of Clinical Surgery, University of Edinburgh, 51

Little France Crescent, Edinburgh EH16 4SA, UK

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World J Surg

https://doi.org/10.1007/s00268-020-05615-x

ﬁxation, and emergency cesarean delivery, and assessed

relative correlations of these postoperative mortality rates.

In order to extract information for emergency laparo-

tomy, emergency cesarean, and open fracture repair, the

authors used 13 procedure codes that involve the opening

of the abdominal cavity and are typically performed as an

emergency (e.g., herniorrhaphy with intestinal resection,

surgical resection of volvulus) to capture the ﬁrst, 3 pro-

cedure codes coupled with emergency designation to cap-

ture the second, and 8 procedures codes pertaining to

internal ﬁxation of fractures of one of four long bones

(humerus, femur, tibia, and ﬁbula) to capture the third.

They showed a correlation between POMR for these

emergency operations and overall postoperative mortality,

although there was a less-strong correlation with individual

Bellwethers.

The routine collection and review of surgical outcomes,

particularly mortality, are an essential characteristic of the

surgical discipline. Providing invasive, high-risk services

demand a commitment to ongoing monitoring, evaluation,

and self-reﬂection. While surgical departments and facili-

ties around the world routinely engage in this exercise,

using these assessments as part of a broader campaign of

surveillance of surgical services is fraught with risk, and

professional, emotional, and legal sensitivities are consid-

erable. Despite this, understanding postoperative mortality

is a crucial metric of global perioperative surveillance. It

was ﬁrst proposed by the World Health Organization in

2008 as part of Safe Surgery Saves Lives [4], and is one of

six key surgical metrics proposed by LCoGS.

Routine collection of such surgical data, including

POMR, is vital for an epidemiological understanding of

surgical access, capacity, and safety, but ensuring these

measures are standardized is also essential. The Bell-

wethers are intended to be representative of surgical

capacity, yet require the creation of a subset of represen-

tative operations, and the authors acknowledge that one

way to overcome this is by using the ‘‘basket’’ approach.

While the Bellwethers represent the treatment of certain

‘‘conditions’’ (the original predicate of the metrics group

from LCoGS), the procedures involved require deﬁnitional

clarity. The Bellwether concept made interpretation of its

meaning a function of author consensus. For example, in a

recent study reporting the LCoGS indicators from

Colombia, in order to identify hospitals capable of pro-

viding these Bellwethers, the authors identiﬁed 41 codes to

determine laparotomy, 7 to determine cesarean, and 62 for

treatment of open fracture [5]. These studies demonstrate

that the current Bellwether terminology, while useful

conceptually, is inadequate for more comprehensive sur-

gical system assessments. The efforts required to craft a set

of procedures codes to represent two of the poorly-deﬁned

Bellwether procedures—exploratory laparotomy and

treatment of open fracture—serve to highlight the need for

something more sophisticated that truly represents the

breadth and depth of surgical, obstetric, and anesthetic

care. The surgical ecosystem is too multifactorial and

complex to be represented by the over-simpliﬁed Bell-

wether procedures as currently articulated. The work to

identify a more comprehensive and representative basket of

operations has begun.

References

1. Meara JG, Leather AJ, Hagander L et al (2015) Global Surgery

2030: evidence and solutions for achieving health, welfare, and

economic development. Lancet 386(9993):569–624

2. O’Neill KM, Greenberg SL, Cherian M et al (2016) Bellwether

procedures for monitoring and planning essential surgical care in

low- and middle-income countries: caesarean delivery, laparo-

tomy, and treatment of open fractures. World J Surg

40(11):2611–2619

3. Truche P, Roa L, Citron I, et al (2020) Bellwether procedures for

monitoring subnational variation of all-cause perioperative mor-

tality in Brazil. World J Surg. https://doi.org/10.1007/s00268-020-

05607-x

4. Weiser TG, Makary MA, Haynes AB, Dziekan G, Berry WR,

Gawande AA (2009) Standardised metrics for global surgical

surveillance. Lancet 374(9695):1113–1117

5. Hanna JS, Herrera-Almario GE, Pinilla-Roncancio M et al (2020)

Use of the six core surgical indicators from the Lancet Commis-

sion on Global Surgery in Colombia: a situational analysis. Lancet

Glob Health 8(5):e699–e710

Publisher’s Note Springer Nature remains neutral with regard to

jurisdictional claims in published maps and institutional afﬁliations.

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