Nadiya Krishnan, Sukhpal Kaur, LN Yaddanapudi


Abstract : Errors are common feature in the complex environments of the Intensive Care Unit (ICU). The aim of the present study was to understand the role of system factors in the precipitation of medical errors. A qualitative approach was adopted to get into the depth of the phenomenon and to have a ‘true picture’ as they evolved and took shape. The researcher mingled and worked with the nursing staff in the main ICU and was engaged in participant observation. Record review and informal interviews were also done to get ‘to the bottom’ of the incidents. The data so collected was analysed by using Colaizzi’s phenomenological data interpretation method and inferences were derived. The data and the interpretation were validated by expert guides for the study.Twelve incidents were recorded and analysed and multiple system based contributing factors were identified. These included latent errors like communication problem, lack of protocol, infrastructure defects, loopholes in supervision etc. Failure to follow protocol and skill based errors were also common in the setting. It was found that most of the errors were limited by chance and that the system factors like supervision, routine audits were not adequate in checking and limiting the effects or preventing the occurrence of errors. System based latent factors are mostly overlooked when an error is analysed. Such an approach leaves the root cause of the error undisturbed in the system thus paving way for later mishaps.

Key words :Medical errors, nursing care, system based latent factors, Qualitative approach

Correspondence at :Nadiya Krishnan, AnandaBhavan, Peruva P.O. , Kottayam Dist., Kerala

Introduction:An intensive care unit (ICU) is a ward in which critically ill patients are kept on life support treatment under intensive monitoring. Doctors, Nurses and technicians vigilantly work on the patients and handle the life suppor t equipment, lines and monitors1.Intensive Care Unit is one of the most expensive components of health care and studies suggest that errors and resulting adverse events are common in the ICU2.Medical errors are human errors in healthcare. By definition, human errors are errors in humanactions. Medical errors are among the most serious quality problems in health care systems and are associated with considerable health-related harm and economic burden3. The most noted work in the field of medical errors was done by British psychologist James Reason4 in 1990 and has since gained widespread acceptance and use in healthcare, in the aviation safety industry, and in emergency service organizations. It is sometimes called the cumulative act effect.Reason’s Swiss cheese model5 explains the complexities of the health care environment and most importantly focuses on the system factors laying latent and predisposing to the error formation. Reason hypothesizes that most accidents can be traced to one or more of four levels of failure: Organizational influences, unsafe supervision, preconditions for unsafe acts, and the unsafe acts themselves. In the Swiss Cheese Model, an organization’s defences against failure are modelled as a series of barriers, represented as slices of Swiss cheese. The holes in the cheese slices represent individual weaknesses in individual parts of the system, and are continually varying in size and position in all slices. The system as a whole produces failures when all of the holes in each of the slices momentarily align, permitting (in Reason’s words) “a trajectory of accident opportunity”, so that a hazard passes through all of the holes in all of the defences, leading to a failure.Nearly  all  adverse  events  involve  a combination of these two sets of factors. Active failures  are the unsafe acts  committed  by people  who are  in  direct  contact  with  the patient or system. They take avariety of forms: slips,  lapses,  fumbles,   mistakes,  and procedural violations. Active failures have a direct and usually short lived impact on the integrity of the defences. Latent conditions are the inevitable “resident pathogens” within the system. They arise from decisions made by designers,builders, procedure writers, and top level management. Such decisions may be mistaken, but they need not be. All such strategic decisions have the potential for introducing pathogens into the system. Latent conditions as the term suggests may lie dormant within the system for many years before they combine with active failures and local triggers to create an accident opportunity. Unlike active failures,whose specific forms are often hard to foresee, latent conditions can be identified and remedied before an adverse event occurs.Understanding this leads to proactive rather than reactive risk management.Latent conditions have two kinds of adverse effect: they can translate into error provoking conditions within the local workplace (for example, time pressure, understaffing, inadequate equipment, fatigue,and inexperience) and they can create long lasting holes or weaknesses in the defences (untrustwor thy alarms and indicators, unworkable procedures, design and construction deficiencies, etc).Many studies have tried to highlight the role of these ‘resident pathogens in the system in the causation of errors. Some of the most commonly identified ones are high or excessive nursing workload 5,6 and many authors have come up asking for staffing makeovers in hospitals to improve patient safety7,8. Fatigue and long working hours, Communication problems between the members of the health care team,lack of experience, training deficits and supervisory deficits was cited as reason in some.Intensive care is one of the most expensive components of health care. As per studies one in five patients in the ICU sustains a serious adverse event. ICU patient care occurs in an unpredictable, technology rich environment that is dependent on highly skilled providers who need constant communication –all features providing the setting for potential error. The accumulation of errors results in accidents. Hence there is an unprecedented need to study the errors and their causative factors in detail. Objective of the study:To explore the ‘critical incidents’ related to the nursing care of the patient admitted in the intensive care unit, Nehru Hospital, PGIMER, Chandigarh. A critical incident was defined as any event or circumstance during the treatment of the patient in the ICU which has led to (or if not detected in time) could have led to an undesirable outcome.Materials and Methods:The study was conducted in the Main Intensive Care Unit of a tertiary care hospital with bed strength of about 1600. The hospital is a premier institution of Medical education and research in the country. The main ICU of the hospital is a 12 bedded multispecialty Intensive Care Unit which caters to medical, neurological, surgical, gynaecological, and other kinds of conditions. The ICU has round the clock presence of Intensivist with three residents being posted both in the morning and night shifts each and a group of consultants to supervise and advise on the management of the patients.There are 39 nurses in the ICU. Out of these, there is one Assistant Nursing Superintend, and one grade I sister for administrative purposes. Rest 36 staff works as bedside nurses.The study population consisted of all the errors occurring in the setting in the presence of the researcher or being reported to the researcher by using an anonymous incident reporting form incident reporting form.The data collection tool was an anonymous critical incident reporting form. It was used to report the critical incidents which occurred in the absence of the researcher. This tool included the incident, date and the time along with its detailed description. Also the respondent was required to give details of the patient like age, sex, diagnosis and the status. The response of the staff to the incident and the outcome was also to be mentioned in the incident report form.The tool was subjected to repeated reviews by experts and guides to make it cater to the study population and the setting.

Methodological congruence:In qualitative research, methodological congruence consists of four components: rigor in documentation, procedural rigor, ethical rigor and auditability (Burns, 1988)9. These criteria were used to address the rigor of this study on critical incidents during nursing care of patients. The essential elements of this research, such as research question, purpose, methodology and the data analysis all have been addressed and gone through multiple rounds of correction by experts in the respective fields. Regarding procedural rigor, the researcher kept a diary where the ‘day to day picture’ regarding events and circumstances of the ICU were being recorded. Also the details of the interviews and record analyses were maintained. Data collection for the study was done through multiple sources like unstructured interview, record analyses (both electronic and char t reviews), observation by the researcher and also using an incident report form. The data so collected was made in to a field report which was analysed by Colaizzi’s method. Also descriptive statistics was used to describe the factors involved.Ethical rigor was maintained. The research was approved by the faculty of NINE and the departmental Head of Anaesthesia and Intensive Care. The sister in charge and the nurses of the ICU were informed of the researcher’s presence and purpose. Auditability, which is the fourth dimension of Burn’s methodological congruence, addressed the decision trail used by the researcher to arrive at the finding from the original data. This was done by submitting the data and the decision trail to my respected guide and co- guide at regular intervals.The data collection was done over a period of six weeks in Aug- Sept 2009. The data covered all the seven days of the week. The researcher was present at the study setting from 8 am to 8 pm for four weeks and 8 pm to 8am for two weeks. In the absence of the researcher, an anonymous incident reporting form was used to report the incidents. The researcher followed up on these incidents on her return to the setting through record analysis and interviews. Data was collected in the form of field reports/ memoing

Data in the field report came from the following methods:

  1. Observation – the researcher was engaged in participatory
  2. Unstructured interview –In depth interviews, which were unstructured and informal in nature, was carried out on the staffs who are involved in the
  3. Record analysis- The researcher went through the various records maintained (electronic and manual) in the setting of the

Results:A total of twelve incidents were analysed and studied. Out of these, nine were observed by the researcher and two were reported using critical incident reporting form. There was mismatch between the number of repor ted and observed incidents. All the incidents occurred within the ICU and during routine care of the patients.Among the precipitating causes of the incidents, system based factors were identified in eleven out of twelve cases. Inadequate supervision and supervisory roles were present in five out of twelve cases.Communications, both inter departmental and intra departmental was a factor in four cases. Similarly, inadequate protocol was identified in five cases. Increased workload complicated /precipitated incidents in four out of twelve cases. Among twelve incidents, two were precipitated by defective

Table 1: Medical errors and system factors identified


no: Description of incident/ error System based latent factors involved
1 Desaturation following suctioning ✓    Communication in between the nurses
2. Ventricular tachycardia and cardiac arrest ✓    Alarm desensitisation
3. Erratic blood sugars following peripheral sampling ✓    Inadequate administrative protocol
in patient with hypotension ✓    Sub- optimal nurse patient ratio
4. Manipulation of alarm limits ✓    Communication
✓    Sub- optimal nurse patient ratio
5. Deterioration of Glasgow Coma Scale in Patient ✓    Sub- optimal nurse patient ratio
✓    Distraction/ inattention precipitated by stress/ workload
✓     Ward administration factors: Staff to be relieved was
given a very sick patient (inadequate supervision)
✓    Inadequate administrative protocol
✓    Improper/ incomplete record maintenance
by both medical and nursing staff
6. Leakage of water into patient cubicle following ✓    Building construction and drainage system
drain block ✓    Lack of Interdisciplinary coordination, communication
and timely response on priority basis
✓    Lack of support staff
7. Low air supply to ICU following disruption in ✓    Communication deficits
pipeline from manifold room ✓    Deficienciesin construction and maintenance of oxygen pipes
✓    Latent errors within the equipment.
8. Displacement of central catheter in restless ✓    Lack of adherence to Sedation wean off patient protocols
` ✓    Disproportionate nurse patient ratio
9. Presence of ampoules of morphine in ✓ (Drug committee) Purchase of different drugs in similar
Adrenaline rack package
✓    Lack of proper policy regarding end use ofnarcotics
✓    Improper supervision
10. Pressure sores following prolonged ✓    Improper supervision
Blood pressure cuff application
  1. Pressure sores following prolonged SPO2 application ✓ Improper supervision
  2. Improper procedure of suctioning ✓ Lack of supplies (sterile gloves, other articles)
    • Improper supervision physical environment including building construction. One incident each was attributed to equipment failure and lack of supplies (Table 1).Among rule based error, failure to follow protocol was seen in four out of twelve incidents. Failure to check equipment and faulty technique was associated with one incident each. Three incidents were precipitated by distraction/ inattention. These mostly involved stress and noise.Coming to the factors limiting the incidents, six out of the twelve were limited by chance (incidental limitation). Prior experience and training was helpful in three out of twelve and skilled assistance in two cases.

Discussions:Phenomenological research based on Heideggerain philosophy10 was used in this study on critical incidents. Phenomenology is the study of lived experience or the life world. Its emphasis is on the world as lived by a person, not the world or the reality as something separate from the person11. Qualitative research methodology is par ticularly useful when problems are complex, contextual, and influenced by the interaction of  physical, psychological and social factors, and thus seems well suited to probing the factors beyond human error and system failure in complex environment of the ICU. The ultimate aim of phenomenological research is to use these descriptions as a ground stone from which to discover underlying commonalities that mark the essential core of the phenomenon.In the first incident, the patient had an episode of desaturation from SpO2 100% to 75%after suctioning. The nurse on duty was newly inducted into the ICU one month before and she was alone at the time of the incident. She was reluctant to call her seniors who were free. Hence she did the suction alone and the patient desaturated as the secretions were thick and copious. Communication has been cited as precipitant in many other studies also.The second, third and fifth incident occurred on the same patient. The patient was unstable and was required multiple inotropes. The second incident was precipitated/ contributed by alarm desensitisation as the nurse on duty could not discriminate between two high priority alarms. She was doing suctioning of the patient on the adjacent bed when the patient had ventricular tachycardia and the monitor gave a red high priority alarm.The nurse who was taking care of this patient had newly joined the institute. Hence she had to attend a compulsory 15 hour orientation programme and she was supposed to attend the classes on the said day along with another staff in the ICU. A third staff had some urgent personal work and she had to take leave for half an hour. All these led to a very low nurse patient ratio in the ICU even though it was morning duty.The nurse was under tremendous stress to complete her tasks in order to be in time for her 11 am class. In this process she unknowingly skips the hourly GCS scoring of the patient. At 12 o clock, the patient was found to be M1 the previous record made was at 8 am which was M5. The patient was immediately taken for a CT scan to find out the cause for the deterioration. A number of studies have identified particular stresses associated with a nurse’s first year of practice55,89. These include discomfort with death and  dying, insufficient knowledge of the unit’s/ hospital’s policies, difficulty in organising workload and managing time. Also, perceived disrespect from more experienced nurses, discomfort with physicians, and the need to be simultaneously autonomous and  receptive to colleague’s help also can contribute to stress in the first year of nursing practice. The study also highlights that a supportive environment can help prevent errors and promote safety89. Similarly there was no protocol for blood sugar sampling of hemodynamically unstable patients. A peripheral sampling was done for hourly glucose monitoring in a patient receiving multiple inotropes including noradrenalin. The patient’s sugar reading was continually low as per these samples and she was given dextrose to maintain blood sugars. At one point, the glucometer read sugar as ‘low’ and the nurse took a central sample this sample gave the glucose measure as 129 mg/dl and all interventions to increase sugars were stopped.My informal interview with the nurse reveals she was aware that inotropes can cause peripheral vasoconstriction. She also acknowledged the fact that the patient was having cold peripheries at the time the sample was taken.Considering the busy schedule that the nurse had on the day, it is fairly possible that she was under tremendous stress to complete her responsibilities. The error was detected only after the staff nurse had left for the class and the next sugar testing was due for the patient.Some of the nurses admitted finding themselves in similar situations when they got conflicting values of central and peripheral sugars. But they never put up the issue with any consultants or senior nurses in order to revise the policy of sampling for blood sugar in hemodynamically compromised patients. Hence there was a lack of initiative on the part of the nurses and the ward administrators to develop practicable, reliable protocols.In the fourth incident the nurse on night duty informed the resident about the fluctuating BP and the resultant monitor alarm. The patient was admitted with status epilepticus and her convulsions were poorly controlled. The resident checked the patient but did not suggest any measures. The same pattern of sudden fluctuations of BP continued many times and ultimately the nurse changed the alarm limits of the monitor from 160/ 100 to 190/120.In the ICU, alarms and clinical tasks are competing for an operator’s attention. Since monitor was already giving alarm and the condition informed to the resident, the nurses in the cubicle felt the alarm as a mere ‘noise’ and increased the alarm limit to ‘get rid’ of it. Hence, the alarm was ignored. This “cry-wolf” effect is a significant detriment to the optimal performance of alarm systems and may result in dire consequences when “true alarms” are ignored12, 13. Noise has been extensively studied and it is documented to cause a variety of disturbances in physiology and psychology. Also, there were communication deficits in between the resident and the nurse. The resident failed to document any measures or continuation of the same measures even thought the problem was repeatedly brought to his notice. The nurse on her part did not clarify the measures to be taken in the current situation and went ahead with manipulation of the alarm. In a patient of status epilepticus, paralysed with neuro muscular blockers, such fluctuations in BP may be the only sign of convulsions.Many of the drugs come in similar packaging. Morphine and adrenaline, calcium gluconate and calcium chloride are easy examples. At two racks, the researcher found morphine ampoules along with adrenaline. They both come in very similar packing. This problem could be happening at multiple places in the hospital involving multiple drugs. And such errors can go unnoticed for long. There is also a risk of misuse of drugs like morphine if its end use is not documented.

Here if we look at the problem deeply, the latent errors become clear

  • Purchase of different drug with similar covering which can predispose to Lack of proper policy regarding the end use of narcotic A proper register indicating the date, time and the name of the patient along with the amount of narcotic use should be maintained thus every ampoule of the drug being taken out of the stock will be accounted for.
  • Improper supervision: The sister in charge makes it a point to take daily rounds of the unit and checks the completion of the crash But she should also do a surprise check on the drugs in the racks.

A multicenter qualitative study evaluating factors that may help or hinder guideline implementation and adherence in the ICU found that an enabling ICU culture, with effective leadership and an ICU team that considered guidelines as essential in reducing practice variation and in achieving best practice, was crucial to a successful guideline programme in the ICU14. Similarly protocol adherence was found to be low in the ICU. The factors responsible for this could be lack of knowledge about the protocol’s existence, lack of knowledge about its importance or the failure of supervisor in implementing the protocol. The protocols most frequently breached included suction protocols, infection control protocols etc. Communication issues precipitated events like lack of interdisciplinary co ordination leading to delay in repair of drain blocks, abrupt cessation of air supply to the ICU due to maintenance work in the manifold rooms.The study helped to reconstruct the experience of ‘living through’ the medical errors and to go beyond the immediately visible and easy to pick up ‘active failures’ to the more complex and shrouded systemic/ latent failures. There are many errors occurring in the Intensive Care Unit which are primarily due to or precipitated by systemic factors. Medical error analysis should adopt a non blaming attitude and look beyond the individual factors and into the latent errors to ‘catch hold’ of loopholes within the system precipitating the errors.Currently there is a shroud of uncertainty and fear which envelops the people involved in medical errors. It will take a lot of concentrated effort on the part of both the individuals and the administrators to look into and acknowledge the role played by system factors in the error precipitation.


  1. Kaur M, Pawar M, Kohli JK, Mishra Critical events in intensive care unit. Indian J Crit Care Med 2008;12:28-31
  2. Pronovost ICU incident reporting systems. J Crit Care 2008;17(2):86 – 94
  3. Kohn LT, Corrigan JM, Donaldson To err is human: building a safer health system. Washington DC: National Academy Press;2000.
  4. Reason J Human error: models and BMJ 2000    March 18;320:768-770
  5. Pronovost PJ, Thompson Toward learning from patient safety reporting systems. J Crit Care. 2006 Dec;21(4):305-15
  6. oreno R Nursing staff in intensive care in Europe: The mismatch between planning and practice:Chest. 1998 Mar;113(3):752-8.
  7. Cheung LYS, Gomersall CD, Lee A, Joynt Is The Nurse Workload: Staffing Ratio Associated with the Outcome of Critically Ill Patients?.Intensive Care Med. 2008 Sept;34(Suppl 1): 5–92.
  8. Kane Nurse staffing and quality of patient care. Agency for Healthcare Research and Quality [online] 2007 Mar [accessed on 2009 Mar 22]; Available from URL nursesttp.htm.
  9. Burns Standards for qualitative research. NursSci Q 2(1):44-52
  10. Heidegger M. Being and New York: Harper;1962.
  11. McNamara Knowing and doing phenomenology: The implications of the critique of ‘nursing phenomenology’ for a phenomenological inquiry: A discussion paper. Int J Nurs Stud 2005 Aug;42(6):695-704.
  12. Chambrin MC. Alarms in the intensive care unit: How can the number of false alarms be reduced? Critical Care 2001 Aug [accessed on 2010 Jan 10]; 5(4). Available from URL: http:// com/content/5/4/184
  13. Schoenberg R, Sands DZ, Safran Making ICU Alarms Meaningful: A comparison of traditional vs. trend-based algorithms. Proc AMIA Symp. 1999: 379–383
  14. Sinuff T, Cook D, Giacomini Facilitating clinician adherence to guideline in the intensive care unit: A multicenter, qualitative study. Crit Care Med 2007;35(9):2083-89