Featured Articles

Safety Investigations from Across the Pond: Deep Learning from England’s Healthcare Safety Investigation Branch (HSIB)

ISMP recently became aware of the Healthcare Safety Investigation Branch (HSIB), an organization that conducts independent investigations of various patient safety concerns in National Health Service (NHS)-funded healthcare across England. The organization, which was established in 2017, is funded by the Department of Health & Social Care and hosted by NHS England and NHS Improvement. HSIB has a team of investigators and analysts with diverse experience in healthcare, human factors, and safety science, who investigate patient safety concerns, identify contributing factors that have led to harm or have the potential to cause harm, and recommend strategies to improve healthcare systems and processes. Central to this is a commitment to a no-blame approach, with investigations providing a ‘safe space’ for participants, including patients, families, and staff, to share information.

HSIB undertakes patient safety investigations through two programs: 1) national investigations of patient safety concerns brought to its attention via an array of information sources, including reports from healthcare organizations and families, and the organization’s own research and analysis; and 2) investigations of all maternity incidents occurring in the NHS. HSIB decides what to investigate based on the scale of risk and harm, the impact on individuals involved, the level of public confidence in healthcare, and the potential for learning to prevent future harm. HSIB recommendations range in scope from those intended for frontline healthcare providers to those directed at the highest levels of national healthcare policy, regulation, and professional standards.  

HSIB Investigative Reports

HSIB national investigations focus on patient safety concerns that have occurred in NHS-funded healthcare after April 2017, and investigations of maternity incidents that have occurred after April 2018. These extensive investigations cover a wide variety of topics, from management of coronavirus (COVID-19) disease transmission risk in hospitals to neonatal collapse during maternal skin-to-skin contact immediately after birth. Medication-related investigations are one of more than a dozen investigative themes. To date, there are four completed and two ongoing medication-related investigations:

  • The role of clinical pharmacy services in helping to identify and reduce high-risk prescribing errors in hospital (completed)

  • Electronic prescribing and medicines administration systems and safe discharge (completed)

  • Potential under-recognized risk of harm from the use of propranolol (completed)

  • Inadvertent administration of an oral liquid medicine into a vein (completed)

  • Prescribing and administering insulin from a pen device in hospital (ongoing)

  • Residual drugs in cannulae and extension lines (ongoing)

Some investigations of patient safety concerns that also involve medications are categorized under different themes, such as “never events” (Administering a wrong site nerve block), “acute” (Timely recognition and treatment of suspected pulmonary embolism in inpatients), “equipment and technology” (Procurement, usability and adoption of “smart” infusion pumps), and “mental health” (Medicine omissions in learning disability secure units).

Investigation of Inadvertent IV Administration of an Oral Liquid Medication

In April 2019, HSIB published an independent report of its investigation of inadvertent administration of an oral liquid medication (midazolam) into a vein.1 An overview of this 88-page investigative report follows.

Background Information. HSIB was made aware of this wrong-route error after the “never event” was reported to the National Reporting and Learning System (NRLS). The investigative report first provides relevant information and cites important literature on medication errors (particularly wrong-route errors), “never events” (particularly intravenous [IV] administration of an oral liquid medication), and midazolam to support the HSIB decision to investigate the safety concern. HSIB concluded that the outcome of inadvertent IV administration of an oral liquid medication can be serious, citing rare deaths and more frequent psychological harm and prolonged patient hospitalization. HSIB concluded that the systemic risk was wide given the evidence from national reporting systems and research that wrong-route errors continue to occur despite initiatives aimed at preventing them. HSIB also concluded that learning from the reference event and a wider investigation of the safety concern would identify best practice strategies to further reduce the risk of errors. Specifically, HSIB set out to examine the reference event to understand the context and causal factors; to review similar incidents to identify common factors; and to examine the role of human factors in inadvertent IV administration of oral liquid medications.

Reference event description. A 9-year-old child (37 kg) was admitted to an ambulatory surgery unit (ASU) for a renal biopsy under moderate sedation. The ASU had not implemented electronic health records (EHRs), so a resident wrote an order for IV midazolam on the patient’s chart, noting a maximum dose of 10 mg (based on official dosing guidelines of 0.4 mg/kg with a 10 mg maximum dose). The resident was unfamiliar with the ASU and asked a nurse to help prepare the midazolam. The nurse who typically prepared medications was absent on the day of the procedure, and an inexperienced nurse was filling in. Fifteen minutes later, the nurse prepared the dose in the treatment room with the resident who had the patient’s chart and order.

In the controlled substance storage location, midazolam ampules (1 mg/mL) were kept alongside a 100 mL bottle of oral liquid midazolam (2.5 mg/mL). The nurse, who was only familiar with oral midazolam, picked up the oral liquid bottle and drew 4 mL (10 mg) of the clear oral medication into an oral/enteral syringe with a purple barrel with the expectation that the medication would be given orally (Figure 1). The nurse and resident verbally checked the medication name, expiration date, dose (based on the patient’s weight), and volume of medication in the syringe. However, they never verified the formulation or route of administration, and neither recognized the error. Furthermore, the resident was unfamiliar with oral/enteral syringes and did not respond to the purple enteral syringe and the “For enteral feeding/med only” warning. The nurse handed the unlabeled syringe to the resident, who took it into the procedure room. 

Figure 1. Purple enteral/oral syringe.
Figure 1. Purple enteral/oral syringe.

In the procedure room, the resident handed the unlabeled syringe to the physician performing the procedure, who clarified the prescribed dose with the resident. When the physician attempted to administer the medication, the syringe would not connect to the IV line, so he asked the resident if the medication in the syringe was IV midazolam. Having been told it was, he asked the resident to put the medication in a “normal” syringe. The resident decanted the contents of the oral/enteral syringe into a Luer lock syringe by connecting the tips of each syringe together and transferring the medication from one to the other. The physician connected the syringe to the patient’s IV line but found it difficult to push the plunger. After administering about 1.5 mL (3.75 mg) of the dose, he stopped and a small amount of the medication leaked onto his gloved hand, feeling sticky and smelling sweet. The physician suspected an error, flushed the line with saline, and asked the resident to clarify the medication with the nurse who prepared it. As soon as the nurse noticed the resident was carrying a parenteral syringe, she recognized the error and the procedure was halted. The patient’s mother was informed of the error, and the child was monitored for the next 24 hours without apparent adverse effects. The next day, the child had the renal biopsy under general anesthesia and was later discharged.

HSIB Investigation

The report describes the HSIB investigation process and conclusions based on their findings. In addition to reviewing medical records, the event report, and policies and procedures, as well as interviewing involved staff, patients and family members, subject matter experts, and national organizations, the investigative process also included: 

National review of similar incidents. When reviewing similar errors reported to national reporting programs, HSIB found that wrong-route errors have shown the largest increase in reporting among all medication event types. The most frequent medications involved in these events were oral liquid morphine, oxyCODONE, sodium valproate, and dispersible aspirin. In 40% of these errors, oral medications had been drawn into IV syringes. In other cases, the medication had been drawn into oral/enteral syringes but   decanted into IV syringes, or oral/enteral syringes were not available.

Review of the literature. While researching inadvertent IV administration of an oral medication, the investigators discovered that the Royal College of Emergency Medicine reported in 2017 that, in a 2-year period, 30% of “never events” occurring in emergency departments were related to the inadvertent IV administration of oral morphine solution. 

Observation. Direct observation of staff related to IV and oral medication storage, prescribing, preparation, and administration found a mismatch in terms of how the work is designed in procedures and guidelines (e.g., work as imagined) and how the work is really carried out (e.g., work as done). Observations of electronic prescribing systems, automated dispensing cabinet storage and retrieval, and barcoded medication administration was also conducted to review opportunities for technological interventions.

Human factors investigation. A human factors expert attended a reconstruction of the reference event and a simulation of what should happen according to documented policies and procedures and identified additional contributing factors, including the similarity of the two formulations of midazolam (both clear liquids); the lack of interaction and communication between team members on the day of the event; ambiguity about what is meant by a two-person check (double check), which is rarely independent; and the overreliance on oral/enteral syringes that are not well-understood by physicians.

Investigative Findings

The report draws dozens of conclusions, a few of which follow:

  • Using oral/enteral syringes does not always prevent wrong-route administration

  • Decanting medication from an oral/enteral syringe into an IV syringe is not an isolated event

  • There appears to be a lack of understanding about the use and purpose of oral/enteral syringes among physicians

  • There is no national standard for two-person checking of medication preparation and administration

  • The training of medical students, residents, and doctors in the preparation and administration of oral and IV medicines is variable, with no formal mandatory standard drug administration training and practical competencies for doctors in hospitals

  • Labeling of practitioner-prepared syringes is inconsistent

  • Staffing shortages combined with good intentions to support colleagues may lead to staff carrying out unfamiliar tasks, resulting in knowledge-based errors


Based on findings from the investigation, HSIB makes recommendations aimed at the local level (specific for the involved organization), organizational level (for all organizations), and national level (for professional, regulatory, and standards organizations). A few examples from each level follow:


  • Develop and implement policies and procedures for invasive procedures that require sedation, including minimum staffing and skill-mix requirements.

  • Educate all clinical staff who prescribe, prepare, and/or administer medications about strategies to prevent wrong-route administration of medications, including the appropriate use of purple oral/enteral syringes.

Organizational level

  • Separate different formulations of the same medication in storage areas.

  • Label practitioner-prepared syringes of medications that are not immediately administered; the person who prepares the medication should administer it.

  • Staff with a responsibility for medication safety should be able to demonstrate how they are learning from medication-related patient safety incidents.

  • HSIB, supported by a teaching hospital, has produced a simulation of what happened during the reference event along with a supplementary teaching aid to increase awareness of this type of error.

  • The investigation team reviewed the opportunities for technological interventions including electronic prescribing systems, automated dispensing cabinets (to limit access to the formulation not ordered), and barcoded medication administration. However, another HSIB investigation was focusing on these technologies; therefore, findings were shared for inclusion in the technology report to prevent duplication.

National level

  • Define a national standard for independent two-person checking when preparing high-risk (high-alert) medications for administration.

  • Create a national audit tool for organizations to use to measure availability of oral/enteral syringes in all clinical areas.  

  • The Royal College of Physicians, Royal College of Nursing, and Royal College of Midwives, in collaboration with the other professional and safety organizations, should recommend postgraduate activities to standardize professional development in medication safety processes; for example, the General Medical Council Medical Licensing Assessment could mandate skills associated with medication administration as part of the Clinical Practical Skills Assessment.


We hope that just a glimpse of this report will help you recognize the depth of learning that is possible when an event is fully investigated by a diverse team discussing each behavioral and system component of the event and then broadly researching all uncovered patient safety issues.


  1. HSIB. Inadvertent administration of an oral liquid medicine into a vein; 12017/009. April 2019;1-88.