The role of checklists in peri-operative care (Haugen)

Quality and safety have been a central focus in peri-operative anaesthesia care, and checklists have been used to get close to zero complications during anaesthesia and surgery. This chapter focuses on the role of surgical safety checklists in peri-operative care (pre-operative, intra-operative and postoperative phases).

Modern history of patient safety started in late 1970s when the cost of malpractice insurance for anaesthesiologists brought patient safety issues to the fore.375 The malpractice crisis forced the American Society of Anesthesiologists (ASA) to address the causes of anaesthesia accidents and to focus on patient safety.376,377 In 1985, the ASA initiated the Anesthesia Patient Safety Foundation, a collaboration between anaesthesia-related professions including anaesthesiologists, nurse anaesthetists, nurses, drug and equipment manufacturers, regulators, insurers and others. The common goal was a zero tolerance for injury of patients with the vision that ‘no patient shall be harmed by anaesthesia’.376,378

Anaesthesia professional organisations have developed international standards for the safe practice of anaesthesia, outlining minimum requirements for performing safe anaesthesia care at a global level,40,379 in the United States377,380 and in Europe12,381–383 ( The EBA and the ESA have produced a European Declaration known as ‘Helsinki Declaration on Patient Safety in Anaesthesiology’.1 This Declaration recommends safety standards including checklists are implemented in peri-operative care.

What is a checklist?

A checklist identifies single items or a group of elements to be verified and checked consecutively and is intended to compensate for memory flaws.384–386 There are two main types of checklists and thus two methods to develop a checklist. The first type is the Do-List, a checklist is used for a step-by-step procedure or task. The second type is the Challenge–Verification–Response, where one person reads aloud the item and challenges someone else to verify and confirm that the task corresponding to the item on the list has been accomplished.385 The Challenge–Verification–Response method is used in the WHO Safe Surgery Saves Lives campaign on how to perform the multidisciplinary team Checklist, the WHO SSC.387

Types and effectiveness of checklists in peri-operative care

Different types of checklists have been developed such as pre-operative briefings and debriefings after surgery,388 “time out” protocols,389 equipment checklists390 and surgical safety checklists.391–393 Pre-operative checks of anaesthetic equipment are embedded in anaesthesia guidelines from Great Britain and Ireland.394,395 In Norway, anaesthesia equipment and machines are now checked electronically prior to induction with a pre-anaesthetic checklist which became possible after the machines evolved from being mechanical to electronically driven.396

In 1998, prior to the introduction of the surgical safety checklists, the US Joint Commission focused on surgical safety issues: operating on the wrong site or the wrong patient, and performing the wrong surgical procedure. In a sentinel event alert they recommended surgical teams to use a ‘time out’ protocol that verifies the identity of the patient, the surgical procedure and the site of surgery by use of active communication techniques ( In 2007, the Royal College of Surgeons of England obligated surgeons to use briefings as a part of their responsibility to safe team behaviour.397

The WHO Surgical Safety Checklist (SSC) was globally introduced in 2008.398 Between October 2007 and September 2008, the checklist was successfully piloted in eight hospitals in eight countries comprising high and low-income status.387 Its effectiveness was examined by comparing errors in patients undergoing noncardiac surgery before (n=3733) and after (n=3955) the introduction of the SSC.393 Complications dropped from 11 to 7% (P < 0.001) and mortality from 1.5 to 0.8% (P = 0.003).393 This publication was the first to evaluate the impact of the WHO SSC in a global population.

Another effective contemporary checklist was the comprehensive surgical patient safety checklist system (SURPASS) developed in the Netherlands,399 based on a literature review of surgical errors and adverse events. The multidisciplinary SURPASS checklist is conducted by different professions along patients’ entire surgical pathway in the hospital. When it was tested in 171 high-risk procedures, 593 process deviations were observed, 96% of which corresponded to a checklist item.399 When comparing the outcome of 3760 patients before and 3820 patients after introducing the SURPASS checklist in Dutch hospitals, the proportion of patients with one or more complications decreased from 15.4 to 10.6% (P < 0.001) and mortality from 1.5 [95% confidence interval (CI) 1.2 to 2.0] to 0.8% (95% CI 0.2 to 1.2), respectively.392 No changes were observed in control hospitals. The SURPASS checklist is currently used in the Netherlands, Canada, India, Sweden and Norway.400,401

The WHO SSC and SURPASS address different aspects of patient safety issues in surgery. Some surgical specialties have developed more procedure-specific checklists. One example is a neurosurgical checklist used in the Mayo Clinic in Arizona. The checklist contains elements of both the time out protocol and the SSC. Over an 8-year period there was a 99.5% compliance rate; no incidents of wrong patient, wrong site or wrong procedure were documented.402

Other checklists have been published, for example, one piloted to detect and remediate procedural errors in movement disorder (deep brain) surgery,403 or the peri-operative team communication checklist is used before patient arrival in the operating theatre for vascular surgery. The team check was developed to promote interprofessional communication and was piloted in 18 surgical procedures. It included team discussions of case-related information, confirmation of details, articulation of concerns, team building and decision-making. This pre-operative team briefing resulted in improved clinical practice, for example, physician compliance with antibiotic administration guidelines.404

To summarise, a variety of peri-operative anaesthesia and surgical checklists have been developed and introduced during the last decades.

How much evidence is needed for using checklists?

Evidence-based medicine seeks to optimise clinicians’ decision-making processes for the individual patient and seeks to set standards. The most stringent evidence for these standards is derived from systematic reviews, meta-analysis and randomised controlled trials, with case series and case reports providing only low level evidence.405 Some of the accepted standards and proposed safety changes in anaesthesia lack high level evidence. Some standards are based on common sense and consensus guidelines, and basically summarise current knowledge and clinical routine (i.e. better equipment and monitoring standards, or electronic information systems).378 Safety advances and a perceived decrease in anaesthesia morbidity and mortality over past decades are attributed to a bundle of changes such as better training, equipment, organisation, supervision, process optimisation and teamwork.378 While not all types of quality improvement can be ‘proven’ by randomised controlled trials,405,406 interventions aimed to improve patient safety ought to be based as much as possible on clinical and theoretical frameworks and robust scientific methodologies with the ultimate goal of determining whether they do more good than harm.405 The available external clinical evidence of the effectiveness of peri-operative checklists has been systematically reviewed.407 The literature search is illustrated in Fig. 6 with a Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram. The identified studies are narratively reported.

Fig 6: Preferred Reporting Items for Systematic Reviews and Meta-Analyses flow diagram of the systematic literature review on surgical safety checklists effects on patient outcome in peri-operative care. (408)


The literature search identified 5810 publications of which 453 were found relevant. Of these, 395 were published in 2013, and 58 in 2019. A total of 32 articles were finally included. The studies are listed alphabetically according to the first author’s names in Table 18.

Table 18: Literature review about effects of surgical safety checklists on morbidity and mortality in peri-operative care


Table 18 (Continued): Literature review about effects of surgical safety checklists on morbidity and mortality in peri-operative care


Table 18 (Continued): Literature review about effects of surgical safety checklists on morbidity and mortality in peri-operative care


The identified original studies investigating the effects of surgical safety checklists on patient outcomes, were published between 2009 and 2019. Of the 32 included studies, effects of the WHO SSC were evaluated in 29 studies,174,409–413,415–437 and the SURPASS checklist in two studies.392,400 One study investigated a surgical safety briefing checklist.414 There are large variations in study sample sizes, ranging from less than 200 patients per group, to millions of patients included in larger population-based studies with pooled analyses over several years (Table 18  ). In 15 studies investigating morbidity, positive effects of the WHO SSC were reported.174,410–412,414–416,419,422,424–426,430–434,437 A smaller proportion of studies (n=6) did not find a significant impact of the WHO SSC on morbidity.409,420,423,427,432,435 In studies evaluating mortality rates, several studies reported that the WHO SSC reduced mortality (n=12).174,395,409,413,414,416–418,421,428,436,437 A stepped wedge cluster randomised controlled trial reported reduced mortality in a subgroup of patients.419 In contrast, other studies (n=5) did not report a significantly decreased mortality with using the checklist.423,425,429,430,435 Studies on the effects of the comprehensive SURPASS checklists used in the entire surgical pathway report a decrease in surgical complications,392,400 and a decreased mortality.392 Two of four studies reporting on WHO SSC effects on readmissions showed decreased readmission rates with using the checklist.424,429 WHO SSC and SURPASS checklists’ impact on length of hospital stay was reported in six studies, with five of these studies reporting a significant reduction in the length of hospital stay.392,413,417,419,429


The current updated review of the literature suggests morbidity and mortality in surgical patients decreases when healthcare personnel use checklists, both intra-operatively (e.g. the WHO SSC) and during peri-postoperative care (e.g. the SURPASS). The cited studies consisted mainly of ‘before and after’ studies (n=24), prevalence cohort design studies (n=4), longitudinal studies (n=2) and randomised controlled trials (n=2). Evidence-based medicine refers to using the best available evidence to address clinically relevant questions.405 The review identified only one stepped wedge cluster randomised controlled trial,419 which has been judged to be the most robust checklist study to-date.438 However, use of the WHO SSC has become mandatory in most hospitals, which makes it challenging to design new randomised controlled trials, especially as the checklists have already been implemented and most likely do more good than harm for patients.

Implementation, compliance and proper use

Implementation of surgical safety checklists requires persistency and long-term perspectives. Conley et al.439 investigated features of effective implementation strategies and found that leaders need to explain to their staff members the ‘why and how’ of the checklist. Staff had to be adequately prepared, otherwise they became frustrated, disinterested and stopped using the checklist despite a hospital-wide mandate.439

Some of the identified studies reported better outcomes when there was higher compliance with the WHO SSC.419,420,426,432,436 This suggests quality improvement reports on compliance rates are very valuable in helping us understand which parts of the checklist work well, and which parts could be omitted. Such reports provide possibilities for more targeted quality improvement interventions. However, compliance rates do not tell us anything about the quality of checklists performance. Production demands and time pressure are elements that may contribute to substandard use of a checklist385,419 as reflected in checklists being used as ‘tick-box’ exercises, the omission of items, or poor team members’ attention.440–443 However, wider implementation and spread of standards like the Helsinki Declaration on Patient Safety in Anaesthesiology,1 and professional associations’ endorsement of safety standards may enhance a culture of safety and promote surgical safety checklists as clinical best practice.379,380,444

Need to change the order of operating room workflow?

When implementing a checklist, we always face the question whether to change our workflow or to adapt the checklist to an established order of work processes. For a successful implementation, the WHO encourages adapting the checklist to local routines and to balance inclusion of important items against brevity of the list.387 Systematic use of checklists may still require the workflow and the order of performing our tasks to be adjusted. The exact timing of when to do the checklist should be agreed upon by all team members. To avoid being perceived as an obstacle, performing the checklist needs to fit into the workflow of the operating room.384 Checklist briefings allow important information to be shared between team members, and provide an opportunity to speak up about any foreseen problem (see also Chapter 3 of this collection).384 When tailoring a surgical checklist, we always face the challenge of inadvertently changing or removing an item or creating a more laborious workflow. To keep attention on critical items (analogous to ‘killer’ items in aviation), the WHO favours not removing items from the original list nor making the list too exhaustive.445 If the WHO SSC is modified it is recommended the WHO adaptation guide be followed.445

Checklist sustainability

Are the effects of the WHO SSC sustainable over time? An investigation based on a large population from Scotland (1998 to 2014) attributed decreased mortality in most of the surgical specialties to checklists.428 Similar findings have been reported in a 5-year retrospective study in Australian hospitals.417 For more procedure-specific pooled analysis of emergency laparotomy procedures in 76 countries, mortality rates were significantly reduced when checklists were used.418 In a large prevalence study from 426 European hospitals, checklist procedures were associated with lower crude mortality.421 Even though other reasons could also explain some of the progress, for example, procedure-specific improvements and focus on patient safety in general, these results suggest that surgical safety checklists have a role in reduction of morbidity and mortality across continents.


Checklists like the WHO SSC and SURPASS represent a number of safety items that jointly can reduce pre-operative, intra-operative and postoperative errors. This updated literature review suggests that use of surgical safety checklists in peri-operative care can reduce morbidity and mortality after surgery.

Please visit the following link to see this article in full on the EJA website